1 | /*
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2 | * ELF file handling for TCC
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3 | *
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4 | * Copyright (c) 2001-2004 Fabrice Bellard
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5 | *
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6 | * This library is free software; you can redistribute it and/or
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7 | * modify it under the terms of the GNU Lesser General Public
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8 | * License as published by the Free Software Foundation; either
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9 | * version 2 of the License, or (at your option) any later version.
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10 | *
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11 | * This library is distributed in the hope that it will be useful,
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12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
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13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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14 | * Lesser General Public License for more details.
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15 | *
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16 | * You should have received a copy of the GNU Lesser General Public
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17 | * License along with this library; if not, write to the Free Software
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18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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19 | */
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20 |
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21 | #include "tcc.h"
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22 |
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23 | /* Define this to get some debug output during relocation processing. */
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24 | #undef DEBUG_RELOC
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25 |
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26 | /********************************************************/
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27 | /* global variables */
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28 |
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29 | ST_DATA Section *text_section, *data_section, *bss_section; /* predefined sections */
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30 | ST_DATA Section *common_section;
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31 | ST_DATA Section *cur_text_section; /* current section where function code is generated */
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32 | #ifdef CONFIG_TCC_ASM
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33 | ST_DATA Section *last_text_section; /* to handle .previous asm directive */
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34 | #endif
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35 | #ifdef CONFIG_TCC_BCHECK
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36 | /* bound check related sections */
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37 | ST_DATA Section *bounds_section; /* contains global data bound description */
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38 | ST_DATA Section *lbounds_section; /* contains local data bound description */
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39 | #endif
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40 | /* symbol sections */
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41 | ST_DATA Section *symtab_section;
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42 | /* debug sections */
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43 | ST_DATA Section *stab_section, *stabstr_section;
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44 |
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45 | /* XXX: avoid static variable */
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46 | static int new_undef_sym = 0; /* Is there a new undefined sym since last new_undef_sym() */
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47 |
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48 | /* special flag to indicate that the section should not be linked to the other ones */
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49 | #define SHF_PRIVATE 0x80000000
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50 | /* section is dynsymtab_section */
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51 | #define SHF_DYNSYM 0x40000000
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52 |
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53 | /* ------------------------------------------------------------------------- */
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54 |
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55 | ST_FUNC void tccelf_new(TCCState *s)
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56 | {
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57 | /* no section zero */
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58 | dynarray_add(&s->sections, &s->nb_sections, NULL);
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59 |
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60 | /* create standard sections */
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61 | text_section = new_section(s, ".text", SHT_PROGBITS, SHF_ALLOC | SHF_EXECINSTR);
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62 | data_section = new_section(s, ".data", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
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63 | bss_section = new_section(s, ".bss", SHT_NOBITS, SHF_ALLOC | SHF_WRITE);
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64 | common_section = new_section(s, ".common", SHT_NOBITS, SHF_PRIVATE);
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65 | common_section->sh_num = SHN_COMMON;
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66 |
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67 | /* symbols are always generated for linking stage */
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68 | symtab_section = new_symtab(s, ".symtab", SHT_SYMTAB, 0,
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69 | ".strtab",
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70 | ".hashtab", SHF_PRIVATE);
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71 | s->symtab = symtab_section;
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72 |
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73 | /* private symbol table for dynamic symbols */
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74 | s->dynsymtab_section = new_symtab(s, ".dynsymtab", SHT_SYMTAB, SHF_PRIVATE|SHF_DYNSYM,
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75 | ".dynstrtab",
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76 | ".dynhashtab", SHF_PRIVATE);
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77 | get_sym_attr(s, 0, 1);
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78 | }
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79 |
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80 | #ifdef CONFIG_TCC_BCHECK
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81 | ST_FUNC void tccelf_bounds_new(TCCState *s)
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82 | {
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83 | /* create bounds sections */
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84 | bounds_section = new_section(s, ".bounds",
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85 | SHT_PROGBITS, SHF_ALLOC);
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86 | lbounds_section = new_section(s, ".lbounds",
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87 | SHT_PROGBITS, SHF_ALLOC);
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88 | }
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89 | #endif
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90 |
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91 | ST_FUNC void tccelf_stab_new(TCCState *s)
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92 | {
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93 | stab_section = new_section(s, ".stab", SHT_PROGBITS, 0);
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94 | stab_section->sh_entsize = sizeof(Stab_Sym);
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95 | stabstr_section = new_section(s, ".stabstr", SHT_STRTAB, 0);
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96 | put_elf_str(stabstr_section, "");
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97 | stab_section->link = stabstr_section;
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98 | /* put first entry */
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99 | put_stabs("", 0, 0, 0, 0);
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100 | }
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101 |
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102 | static void free_section(Section *s)
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103 | {
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104 | tcc_free(s->data);
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105 | }
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106 |
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107 | ST_FUNC void tccelf_delete(TCCState *s1)
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108 | {
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109 | int i;
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110 |
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111 | /* free all sections */
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112 | for(i = 1; i < s1->nb_sections; i++)
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113 | free_section(s1->sections[i]);
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114 | dynarray_reset(&s1->sections, &s1->nb_sections);
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115 |
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116 | for(i = 0; i < s1->nb_priv_sections; i++)
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117 | free_section(s1->priv_sections[i]);
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118 | dynarray_reset(&s1->priv_sections, &s1->nb_priv_sections);
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119 |
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120 | /* free any loaded DLLs */
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121 | #ifdef TCC_IS_NATIVE
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122 | for ( i = 0; i < s1->nb_loaded_dlls; i++) {
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123 | DLLReference *ref = s1->loaded_dlls[i];
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124 | if ( ref->handle )
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125 | # ifdef _WIN32
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126 | FreeLibrary((HMODULE)ref->handle);
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127 | # else
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128 | dlclose(ref->handle);
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129 | # endif
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130 | }
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131 | #endif
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132 | /* free loaded dlls array */
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133 | dynarray_reset(&s1->loaded_dlls, &s1->nb_loaded_dlls);
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134 | tcc_free(s1->sym_attrs);
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135 |
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136 | symtab_section = NULL; /* for tccrun.c:rt_printline() */
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137 | }
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138 |
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139 | /* save section data state */
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140 | ST_FUNC void tccelf_begin_file(TCCState *s1)
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141 | {
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142 | Section *s; int i;
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143 | for (i = 1; i < s1->nb_sections; i++) {
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144 | s = s1->sections[i];
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145 | s->sh_offset = s->data_offset;
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146 | }
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147 | /* disable symbol hashing during compilation */
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148 | s = s1->symtab, s->reloc = s->hash, s->hash = NULL;
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149 | #if defined TCC_TARGET_X86_64 && defined TCC_TARGET_PE
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150 | s1->uw_sym = 0;
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151 | #endif
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152 | }
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153 |
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154 | /* At the end of compilation, convert any UNDEF syms to global, and merge
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155 | with previously existing symbols */
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156 | ST_FUNC void tccelf_end_file(TCCState *s1)
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157 | {
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158 | Section *s = s1->symtab;
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159 | int first_sym, nb_syms, *tr, i;
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160 |
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161 | first_sym = s->sh_offset / sizeof (ElfSym);
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162 | nb_syms = s->data_offset / sizeof (ElfSym) - first_sym;
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163 | s->data_offset = s->sh_offset;
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164 | s->link->data_offset = s->link->sh_offset;
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165 | s->hash = s->reloc, s->reloc = NULL;
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166 | tr = tcc_mallocz(nb_syms * sizeof *tr);
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167 |
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168 | for (i = 0; i < nb_syms; ++i) {
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169 | ElfSym *sym = (ElfSym*)s->data + first_sym + i;
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170 | if (sym->st_shndx == SHN_UNDEF
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171 | && ELFW(ST_BIND)(sym->st_info) == STB_LOCAL)
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172 | sym->st_info = ELFW(ST_INFO)(STB_GLOBAL, ELFW(ST_TYPE)(sym->st_info));
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173 | tr[i] = set_elf_sym(s, sym->st_value, sym->st_size, sym->st_info,
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174 | sym->st_other, sym->st_shndx, s->link->data + sym->st_name);
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175 | }
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176 | /* now update relocations */
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177 | for (i = 1; i < s1->nb_sections; i++) {
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178 | Section *sr = s1->sections[i];
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179 | if (sr->sh_type == SHT_RELX && sr->link == s) {
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180 | ElfW_Rel *rel = (ElfW_Rel*)(sr->data + sr->sh_offset);
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181 | ElfW_Rel *rel_end = (ElfW_Rel*)(sr->data + sr->data_offset);
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182 | for (; rel < rel_end; ++rel) {
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183 | int n = ELFW(R_SYM)(rel->r_info) - first_sym;
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184 | //if (n < 0) tcc_error("internal: invalid symbol index in relocation");
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185 | rel->r_info = ELFW(R_INFO)(tr[n], ELFW(R_TYPE)(rel->r_info));
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186 | }
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187 | }
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188 | }
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189 | tcc_free(tr);
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190 | }
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191 |
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192 | ST_FUNC Section *new_section(TCCState *s1, const char *name, int sh_type, int sh_flags)
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193 | {
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194 | Section *sec;
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195 |
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196 | sec = tcc_mallocz(sizeof(Section) + strlen(name));
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197 | strcpy(sec->name, name);
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198 | sec->sh_type = sh_type;
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199 | sec->sh_flags = sh_flags;
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200 | switch(sh_type) {
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201 | case SHT_HASH:
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202 | case SHT_REL:
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203 | case SHT_RELA:
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204 | case SHT_DYNSYM:
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205 | case SHT_SYMTAB:
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206 | case SHT_DYNAMIC:
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207 | sec->sh_addralign = 4;
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208 | break;
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209 | case SHT_STRTAB:
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210 | sec->sh_addralign = 1;
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211 | break;
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212 | default:
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213 | sec->sh_addralign = PTR_SIZE; /* gcc/pcc default alignment */
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214 | break;
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215 | }
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216 |
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217 | if (sh_flags & SHF_PRIVATE) {
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218 | dynarray_add(&s1->priv_sections, &s1->nb_priv_sections, sec);
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219 | } else {
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220 | sec->sh_num = s1->nb_sections;
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221 | dynarray_add(&s1->sections, &s1->nb_sections, sec);
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222 | }
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223 |
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224 | return sec;
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225 | }
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226 |
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227 | ST_FUNC Section *new_symtab(TCCState *s1,
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228 | const char *symtab_name, int sh_type, int sh_flags,
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229 | const char *strtab_name,
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230 | const char *hash_name, int hash_sh_flags)
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231 | {
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232 | Section *symtab, *strtab, *hash;
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233 | int *ptr, nb_buckets;
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234 |
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235 | symtab = new_section(s1, symtab_name, sh_type, sh_flags);
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236 | symtab->sh_entsize = sizeof(ElfW(Sym));
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237 | strtab = new_section(s1, strtab_name, SHT_STRTAB, sh_flags);
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238 | put_elf_str(strtab, "");
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239 | symtab->link = strtab;
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240 | put_elf_sym(symtab, 0, 0, 0, 0, 0, NULL);
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241 |
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242 | nb_buckets = 1;
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243 |
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244 | hash = new_section(s1, hash_name, SHT_HASH, hash_sh_flags);
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245 | hash->sh_entsize = sizeof(int);
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246 | symtab->hash = hash;
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247 | hash->link = symtab;
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248 |
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249 | ptr = section_ptr_add(hash, (2 + nb_buckets + 1) * sizeof(int));
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250 | ptr[0] = nb_buckets;
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251 | ptr[1] = 1;
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252 | memset(ptr + 2, 0, (nb_buckets + 1) * sizeof(int));
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253 | return symtab;
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254 | }
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255 |
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256 | /* realloc section and set its content to zero */
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257 | ST_FUNC void section_realloc(Section *sec, unsigned long new_size)
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258 | {
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259 | unsigned long size;
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260 | unsigned char *data;
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261 |
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262 | size = sec->data_allocated;
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263 | if (size == 0)
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264 | size = 1;
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265 | while (size < new_size)
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266 | size = size * 2;
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267 | data = tcc_realloc(sec->data, size);
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268 | memset(data + sec->data_allocated, 0, size - sec->data_allocated);
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269 | sec->data = data;
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270 | sec->data_allocated = size;
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271 | }
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272 |
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273 | /* reserve at least 'size' bytes aligned per 'align' in section
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274 | 'sec' from current offset, and return the aligned offset */
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275 | ST_FUNC size_t section_add(Section *sec, addr_t size, int align)
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276 | {
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277 | size_t offset, offset1;
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278 |
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279 | offset = (sec->data_offset + align - 1) & -align;
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280 | offset1 = offset + size;
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281 | if (sec->sh_type != SHT_NOBITS && offset1 > sec->data_allocated)
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282 | section_realloc(sec, offset1);
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283 | sec->data_offset = offset1;
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284 | if (align > sec->sh_addralign)
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285 | sec->sh_addralign = align;
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286 | return offset;
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287 | }
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288 |
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289 | /* reserve at least 'size' bytes in section 'sec' from
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290 | sec->data_offset. */
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291 | ST_FUNC void *section_ptr_add(Section *sec, addr_t size)
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292 | {
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293 | size_t offset = section_add(sec, size, 1);
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294 | return sec->data + offset;
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295 | }
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296 |
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297 | /* reserve at least 'size' bytes from section start */
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298 | ST_FUNC void section_reserve(Section *sec, unsigned long size)
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299 | {
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300 | if (size > sec->data_allocated)
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301 | section_realloc(sec, size);
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302 | if (size > sec->data_offset)
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303 | sec->data_offset = size;
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304 | }
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305 |
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306 | /* return a reference to a section, and create it if it does not
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307 | exists */
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308 | ST_FUNC Section *find_section(TCCState *s1, const char *name)
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309 | {
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310 | Section *sec;
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311 | int i;
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312 | for(i = 1; i < s1->nb_sections; i++) {
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313 | sec = s1->sections[i];
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314 | if (!strcmp(name, sec->name))
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315 | return sec;
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316 | }
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317 | /* sections are created as PROGBITS */
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318 | return new_section(s1, name, SHT_PROGBITS, SHF_ALLOC);
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319 | }
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320 |
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321 | /* ------------------------------------------------------------------------- */
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322 |
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323 | ST_FUNC int put_elf_str(Section *s, const char *sym)
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324 | {
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325 | int offset, len;
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326 | char *ptr;
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327 |
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328 | len = strlen(sym) + 1;
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329 | offset = s->data_offset;
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330 | ptr = section_ptr_add(s, len);
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331 | memmove(ptr, sym, len);
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332 | return offset;
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333 | }
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334 |
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335 | /* elf symbol hashing function */
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336 | static unsigned long elf_hash(const unsigned char *name)
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337 | {
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338 | unsigned long h = 0, g;
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339 |
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340 | while (*name) {
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341 | h = (h << 4) + *name++;
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342 | g = h & 0xf0000000;
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343 | if (g)
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344 | h ^= g >> 24;
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345 | h &= ~g;
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346 | }
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347 | return h;
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348 | }
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349 |
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350 | /* rebuild hash table of section s */
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351 | /* NOTE: we do factorize the hash table code to go faster */
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352 | static void rebuild_hash(Section *s, unsigned int nb_buckets)
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353 | {
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354 | ElfW(Sym) *sym;
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355 | int *ptr, *hash, nb_syms, sym_index, h;
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356 | unsigned char *strtab;
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357 |
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358 | strtab = s->link->data;
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359 | nb_syms = s->data_offset / sizeof(ElfW(Sym));
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360 |
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361 | if (!nb_buckets)
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362 | nb_buckets = ((int*)s->hash->data)[0];
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363 |
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364 | s->hash->data_offset = 0;
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365 | ptr = section_ptr_add(s->hash, (2 + nb_buckets + nb_syms) * sizeof(int));
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366 | ptr[0] = nb_buckets;
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367 | ptr[1] = nb_syms;
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368 | ptr += 2;
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369 | hash = ptr;
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370 | memset(hash, 0, (nb_buckets + 1) * sizeof(int));
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371 | ptr += nb_buckets + 1;
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372 |
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373 | sym = (ElfW(Sym) *)s->data + 1;
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374 | for(sym_index = 1; sym_index < nb_syms; sym_index++) {
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375 | if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
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376 | h = elf_hash(strtab + sym->st_name) % nb_buckets;
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377 | *ptr = hash[h];
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378 | hash[h] = sym_index;
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379 | } else {
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380 | *ptr = 0;
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381 | }
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382 | ptr++;
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383 | sym++;
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384 | }
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385 | }
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386 |
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387 | /* return the symbol number */
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388 | ST_FUNC int put_elf_sym(Section *s, addr_t value, unsigned long size,
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389 | int info, int other, int shndx, const char *name)
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390 | {
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391 | int name_offset, sym_index;
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392 | int nbuckets, h;
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393 | ElfW(Sym) *sym;
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394 | Section *hs;
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395 |
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396 | sym = section_ptr_add(s, sizeof(ElfW(Sym)));
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397 | if (name && name[0])
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398 | name_offset = put_elf_str(s->link, name);
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399 | else
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400 | name_offset = 0;
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401 | /* XXX: endianness */
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402 | sym->st_name = name_offset;
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403 | sym->st_value = value;
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404 | sym->st_size = size;
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405 | sym->st_info = info;
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406 | sym->st_other = other;
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407 | sym->st_shndx = shndx;
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408 | sym_index = sym - (ElfW(Sym) *)s->data;
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409 | hs = s->hash;
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410 | if (hs) {
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411 | int *ptr, *base;
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412 | ptr = section_ptr_add(hs, sizeof(int));
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413 | base = (int *)hs->data;
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414 | /* only add global or weak symbols. */
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415 | if (ELFW(ST_BIND)(info) != STB_LOCAL) {
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416 | /* add another hashing entry */
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417 | nbuckets = base[0];
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418 | h = elf_hash((unsigned char *)s->link->data + name_offset) % nbuckets;
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419 | *ptr = base[2 + h];
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420 | base[2 + h] = sym_index;
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421 | base[1]++;
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422 | /* we resize the hash table */
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423 | hs->nb_hashed_syms++;
|
---|
424 | if (hs->nb_hashed_syms > 2 * nbuckets) {
|
---|
425 | rebuild_hash(s, 2 * nbuckets);
|
---|
426 | }
|
---|
427 | } else {
|
---|
428 | *ptr = 0;
|
---|
429 | base[1]++;
|
---|
430 | }
|
---|
431 | }
|
---|
432 | return sym_index;
|
---|
433 | }
|
---|
434 |
|
---|
435 | ST_FUNC int find_elf_sym(Section *s, const char *name)
|
---|
436 | {
|
---|
437 | ElfW(Sym) *sym;
|
---|
438 | Section *hs;
|
---|
439 | int nbuckets, sym_index, h;
|
---|
440 | const char *name1;
|
---|
441 |
|
---|
442 | hs = s->hash;
|
---|
443 | if (!hs)
|
---|
444 | return 0;
|
---|
445 | nbuckets = ((int *)hs->data)[0];
|
---|
446 | h = elf_hash((unsigned char *) name) % nbuckets;
|
---|
447 | sym_index = ((int *)hs->data)[2 + h];
|
---|
448 | while (sym_index != 0) {
|
---|
449 | sym = &((ElfW(Sym) *)s->data)[sym_index];
|
---|
450 | name1 = (char *) s->link->data + sym->st_name;
|
---|
451 | if (!strcmp(name, name1))
|
---|
452 | return sym_index;
|
---|
453 | sym_index = ((int *)hs->data)[2 + nbuckets + sym_index];
|
---|
454 | }
|
---|
455 | return 0;
|
---|
456 | }
|
---|
457 |
|
---|
458 | /* return elf symbol value, signal error if 'err' is nonzero */
|
---|
459 | ST_FUNC addr_t get_elf_sym_addr(TCCState *s, const char *name, int err)
|
---|
460 | {
|
---|
461 | int sym_index;
|
---|
462 | ElfW(Sym) *sym;
|
---|
463 |
|
---|
464 | sym_index = find_elf_sym(s->symtab, name);
|
---|
465 | sym = &((ElfW(Sym) *)s->symtab->data)[sym_index];
|
---|
466 | if (!sym_index || sym->st_shndx == SHN_UNDEF) {
|
---|
467 | if (err)
|
---|
468 | tcc_error("%s not defined", name);
|
---|
469 | return 0;
|
---|
470 | }
|
---|
471 | return sym->st_value;
|
---|
472 | }
|
---|
473 |
|
---|
474 | /* return elf symbol value */
|
---|
475 | LIBTCCAPI void *tcc_get_symbol(TCCState *s, const char *name)
|
---|
476 | {
|
---|
477 | return (void*)(uintptr_t)get_elf_sym_addr(s, name, 0);
|
---|
478 | }
|
---|
479 |
|
---|
480 | #if defined TCC_IS_NATIVE || defined TCC_TARGET_PE
|
---|
481 | /* return elf symbol value or error */
|
---|
482 | ST_FUNC void* tcc_get_symbol_err(TCCState *s, const char *name)
|
---|
483 | {
|
---|
484 | return (void*)(uintptr_t)get_elf_sym_addr(s, name, 1);
|
---|
485 | }
|
---|
486 | #endif
|
---|
487 |
|
---|
488 | /* add an elf symbol : check if it is already defined and patch
|
---|
489 | it. Return symbol index. NOTE that sh_num can be SHN_UNDEF. */
|
---|
490 | ST_FUNC int set_elf_sym(Section *s, addr_t value, unsigned long size,
|
---|
491 | int info, int other, int shndx, const char *name)
|
---|
492 | {
|
---|
493 | ElfW(Sym) *esym;
|
---|
494 | int sym_bind, sym_index, sym_type, esym_bind;
|
---|
495 | unsigned char sym_vis, esym_vis, new_vis;
|
---|
496 |
|
---|
497 | sym_bind = ELFW(ST_BIND)(info);
|
---|
498 | sym_type = ELFW(ST_TYPE)(info);
|
---|
499 | sym_vis = ELFW(ST_VISIBILITY)(other);
|
---|
500 |
|
---|
501 | if (sym_bind != STB_LOCAL) {
|
---|
502 | /* we search global or weak symbols */
|
---|
503 | sym_index = find_elf_sym(s, name);
|
---|
504 | if (!sym_index)
|
---|
505 | goto do_def;
|
---|
506 | esym = &((ElfW(Sym) *)s->data)[sym_index];
|
---|
507 | if (esym->st_value == value && esym->st_size == size && esym->st_info == info
|
---|
508 | && esym->st_other == other && esym->st_shndx == shndx)
|
---|
509 | return sym_index;
|
---|
510 | if (esym->st_shndx != SHN_UNDEF) {
|
---|
511 | esym_bind = ELFW(ST_BIND)(esym->st_info);
|
---|
512 | /* propagate the most constraining visibility */
|
---|
513 | /* STV_DEFAULT(0)<STV_PROTECTED(3)<STV_HIDDEN(2)<STV_INTERNAL(1) */
|
---|
514 | esym_vis = ELFW(ST_VISIBILITY)(esym->st_other);
|
---|
515 | if (esym_vis == STV_DEFAULT) {
|
---|
516 | new_vis = sym_vis;
|
---|
517 | } else if (sym_vis == STV_DEFAULT) {
|
---|
518 | new_vis = esym_vis;
|
---|
519 | } else {
|
---|
520 | new_vis = (esym_vis < sym_vis) ? esym_vis : sym_vis;
|
---|
521 | }
|
---|
522 | esym->st_other = (esym->st_other & ~ELFW(ST_VISIBILITY)(-1))
|
---|
523 | | new_vis;
|
---|
524 | other = esym->st_other; /* in case we have to patch esym */
|
---|
525 | if (shndx == SHN_UNDEF) {
|
---|
526 | /* ignore adding of undefined symbol if the
|
---|
527 | corresponding symbol is already defined */
|
---|
528 | } else if (sym_bind == STB_GLOBAL && esym_bind == STB_WEAK) {
|
---|
529 | /* global overrides weak, so patch */
|
---|
530 | goto do_patch;
|
---|
531 | } else if (sym_bind == STB_WEAK && esym_bind == STB_GLOBAL) {
|
---|
532 | /* weak is ignored if already global */
|
---|
533 | } else if (sym_bind == STB_WEAK && esym_bind == STB_WEAK) {
|
---|
534 | /* keep first-found weak definition, ignore subsequents */
|
---|
535 | } else if (sym_vis == STV_HIDDEN || sym_vis == STV_INTERNAL) {
|
---|
536 | /* ignore hidden symbols after */
|
---|
537 | } else if ((esym->st_shndx == SHN_COMMON
|
---|
538 | || esym->st_shndx == bss_section->sh_num)
|
---|
539 | && (shndx < SHN_LORESERVE
|
---|
540 | && shndx != bss_section->sh_num)) {
|
---|
541 | /* data symbol gets precedence over common/bss */
|
---|
542 | goto do_patch;
|
---|
543 | } else if (shndx == SHN_COMMON || shndx == bss_section->sh_num) {
|
---|
544 | /* data symbol keeps precedence over common/bss */
|
---|
545 | } else if (s->sh_flags & SHF_DYNSYM) {
|
---|
546 | /* we accept that two DLL define the same symbol */
|
---|
547 | } else if (esym->st_other & ST_ASM_SET) {
|
---|
548 | /* If the existing symbol came from an asm .set
|
---|
549 | we can override. */
|
---|
550 | goto do_patch;
|
---|
551 | } else {
|
---|
552 | #if 0
|
---|
553 | printf("new_bind=%x new_shndx=%x new_vis=%x old_bind=%x old_shndx=%x old_vis=%x\n",
|
---|
554 | sym_bind, shndx, new_vis, esym_bind, esym->st_shndx, esym_vis);
|
---|
555 | #endif
|
---|
556 | tcc_error_noabort("'%s' defined twice", name);
|
---|
557 | }
|
---|
558 | } else {
|
---|
559 | do_patch:
|
---|
560 | esym->st_info = ELFW(ST_INFO)(sym_bind, sym_type);
|
---|
561 | esym->st_shndx = shndx;
|
---|
562 | new_undef_sym = 1;
|
---|
563 | esym->st_value = value;
|
---|
564 | esym->st_size = size;
|
---|
565 | esym->st_other = other;
|
---|
566 | }
|
---|
567 | } else {
|
---|
568 | do_def:
|
---|
569 | sym_index = put_elf_sym(s, value, size,
|
---|
570 | ELFW(ST_INFO)(sym_bind, sym_type), other,
|
---|
571 | shndx, name);
|
---|
572 | }
|
---|
573 | return sym_index;
|
---|
574 | }
|
---|
575 |
|
---|
576 | /* put relocation */
|
---|
577 | ST_FUNC void put_elf_reloca(Section *symtab, Section *s, unsigned long offset,
|
---|
578 | int type, int symbol, addr_t addend)
|
---|
579 | {
|
---|
580 | char buf[256];
|
---|
581 | Section *sr;
|
---|
582 | ElfW_Rel *rel;
|
---|
583 |
|
---|
584 | sr = s->reloc;
|
---|
585 | if (!sr) {
|
---|
586 | /* if no relocation section, create it */
|
---|
587 | snprintf(buf, sizeof(buf), REL_SECTION_FMT, s->name);
|
---|
588 | /* if the symtab is allocated, then we consider the relocation
|
---|
589 | are also */
|
---|
590 | sr = new_section(tcc_state, buf, SHT_RELX, symtab->sh_flags);
|
---|
591 | sr->sh_entsize = sizeof(ElfW_Rel);
|
---|
592 | sr->link = symtab;
|
---|
593 | sr->sh_info = s->sh_num;
|
---|
594 | s->reloc = sr;
|
---|
595 | }
|
---|
596 | rel = section_ptr_add(sr, sizeof(ElfW_Rel));
|
---|
597 | rel->r_offset = offset;
|
---|
598 | rel->r_info = ELFW(R_INFO)(symbol, type);
|
---|
599 | #if SHT_RELX == SHT_RELA
|
---|
600 | rel->r_addend = addend;
|
---|
601 | #else
|
---|
602 | if (addend)
|
---|
603 | tcc_error("non-zero addend on REL architecture");
|
---|
604 | #endif
|
---|
605 | }
|
---|
606 |
|
---|
607 | ST_FUNC void put_elf_reloc(Section *symtab, Section *s, unsigned long offset,
|
---|
608 | int type, int symbol)
|
---|
609 | {
|
---|
610 | put_elf_reloca(symtab, s, offset, type, symbol, 0);
|
---|
611 | }
|
---|
612 |
|
---|
613 | /* Remove relocations for section S->reloc starting at oldrelocoffset
|
---|
614 | that are to the same place, retaining the last of them. As side effect
|
---|
615 | the relocations are sorted. Possibly reduces the number of relocs. */
|
---|
616 | ST_FUNC void squeeze_multi_relocs(Section *s, size_t oldrelocoffset)
|
---|
617 | {
|
---|
618 | Section *sr = s->reloc;
|
---|
619 | ElfW_Rel *r, *dest;
|
---|
620 | ssize_t a;
|
---|
621 | ElfW(Addr) addr;
|
---|
622 |
|
---|
623 | if (oldrelocoffset + sizeof(*r) >= sr->data_offset)
|
---|
624 | return;
|
---|
625 | /* The relocs we're dealing with are the result of initializer parsing.
|
---|
626 | So they will be mostly in order and there aren't many of them.
|
---|
627 | Secondly we need a stable sort (which qsort isn't). We use
|
---|
628 | a simple insertion sort. */
|
---|
629 | for (a = oldrelocoffset + sizeof(*r); a < sr->data_offset; a += sizeof(*r)) {
|
---|
630 | ssize_t i = a - sizeof(*r);
|
---|
631 | addr = ((ElfW_Rel*)(sr->data + a))->r_offset;
|
---|
632 | for (; i >= (ssize_t)oldrelocoffset &&
|
---|
633 | ((ElfW_Rel*)(sr->data + i))->r_offset > addr; i -= sizeof(*r)) {
|
---|
634 | ElfW_Rel tmp = *(ElfW_Rel*)(sr->data + a);
|
---|
635 | *(ElfW_Rel*)(sr->data + a) = *(ElfW_Rel*)(sr->data + i);
|
---|
636 | *(ElfW_Rel*)(sr->data + i) = tmp;
|
---|
637 | }
|
---|
638 | }
|
---|
639 |
|
---|
640 | r = (ElfW_Rel*)(sr->data + oldrelocoffset);
|
---|
641 | dest = r;
|
---|
642 | for (; r < (ElfW_Rel*)(sr->data + sr->data_offset); r++) {
|
---|
643 | if (dest->r_offset != r->r_offset)
|
---|
644 | dest++;
|
---|
645 | *dest = *r;
|
---|
646 | }
|
---|
647 | sr->data_offset = (unsigned char*)dest - sr->data + sizeof(*r);
|
---|
648 | }
|
---|
649 |
|
---|
650 | /* put stab debug information */
|
---|
651 |
|
---|
652 | ST_FUNC void put_stabs(const char *str, int type, int other, int desc,
|
---|
653 | unsigned long value)
|
---|
654 | {
|
---|
655 | Stab_Sym *sym;
|
---|
656 |
|
---|
657 | sym = section_ptr_add(stab_section, sizeof(Stab_Sym));
|
---|
658 | if (str) {
|
---|
659 | sym->n_strx = put_elf_str(stabstr_section, str);
|
---|
660 | } else {
|
---|
661 | sym->n_strx = 0;
|
---|
662 | }
|
---|
663 | sym->n_type = type;
|
---|
664 | sym->n_other = other;
|
---|
665 | sym->n_desc = desc;
|
---|
666 | sym->n_value = value;
|
---|
667 | }
|
---|
668 |
|
---|
669 | ST_FUNC void put_stabs_r(const char *str, int type, int other, int desc,
|
---|
670 | unsigned long value, Section *sec, int sym_index)
|
---|
671 | {
|
---|
672 | put_stabs(str, type, other, desc, value);
|
---|
673 | put_elf_reloc(symtab_section, stab_section,
|
---|
674 | stab_section->data_offset - sizeof(unsigned int),
|
---|
675 | R_DATA_32, sym_index);
|
---|
676 | }
|
---|
677 |
|
---|
678 | ST_FUNC void put_stabn(int type, int other, int desc, int value)
|
---|
679 | {
|
---|
680 | put_stabs(NULL, type, other, desc, value);
|
---|
681 | }
|
---|
682 |
|
---|
683 | ST_FUNC void put_stabd(int type, int other, int desc)
|
---|
684 | {
|
---|
685 | put_stabs(NULL, type, other, desc, 0);
|
---|
686 | }
|
---|
687 |
|
---|
688 | ST_FUNC struct sym_attr *get_sym_attr(TCCState *s1, int index, int alloc)
|
---|
689 | {
|
---|
690 | int n;
|
---|
691 | struct sym_attr *tab;
|
---|
692 |
|
---|
693 | if (index >= s1->nb_sym_attrs) {
|
---|
694 | if (!alloc)
|
---|
695 | return s1->sym_attrs;
|
---|
696 | /* find immediately bigger power of 2 and reallocate array */
|
---|
697 | n = 1;
|
---|
698 | while (index >= n)
|
---|
699 | n *= 2;
|
---|
700 | tab = tcc_realloc(s1->sym_attrs, n * sizeof(*s1->sym_attrs));
|
---|
701 | s1->sym_attrs = tab;
|
---|
702 | memset(s1->sym_attrs + s1->nb_sym_attrs, 0,
|
---|
703 | (n - s1->nb_sym_attrs) * sizeof(*s1->sym_attrs));
|
---|
704 | s1->nb_sym_attrs = n;
|
---|
705 | }
|
---|
706 | return &s1->sym_attrs[index];
|
---|
707 | }
|
---|
708 |
|
---|
709 | /* Browse each elem of type <type> in section <sec> starting at elem <startoff>
|
---|
710 | using variable <elem> */
|
---|
711 | #define for_each_elem(sec, startoff, elem, type) \
|
---|
712 | for (elem = (type *) sec->data + startoff; \
|
---|
713 | elem < (type *) (sec->data + sec->data_offset); elem++)
|
---|
714 |
|
---|
715 | /* In an ELF file symbol table, the local symbols must appear below
|
---|
716 | the global and weak ones. Since TCC cannot sort it while generating
|
---|
717 | the code, we must do it after. All the relocation tables are also
|
---|
718 | modified to take into account the symbol table sorting */
|
---|
719 | static void sort_syms(TCCState *s1, Section *s)
|
---|
720 | {
|
---|
721 | int *old_to_new_syms;
|
---|
722 | ElfW(Sym) *new_syms;
|
---|
723 | int nb_syms, i;
|
---|
724 | ElfW(Sym) *p, *q;
|
---|
725 | ElfW_Rel *rel;
|
---|
726 | Section *sr;
|
---|
727 | int type, sym_index;
|
---|
728 |
|
---|
729 | nb_syms = s->data_offset / sizeof(ElfW(Sym));
|
---|
730 | new_syms = tcc_malloc(nb_syms * sizeof(ElfW(Sym)));
|
---|
731 | old_to_new_syms = tcc_malloc(nb_syms * sizeof(int));
|
---|
732 |
|
---|
733 | /* first pass for local symbols */
|
---|
734 | p = (ElfW(Sym) *)s->data;
|
---|
735 | q = new_syms;
|
---|
736 | for(i = 0; i < nb_syms; i++) {
|
---|
737 | if (ELFW(ST_BIND)(p->st_info) == STB_LOCAL) {
|
---|
738 | old_to_new_syms[i] = q - new_syms;
|
---|
739 | *q++ = *p;
|
---|
740 | }
|
---|
741 | p++;
|
---|
742 | }
|
---|
743 | /* save the number of local symbols in section header */
|
---|
744 | if( s->sh_size ) /* this 'if' makes IDA happy */
|
---|
745 | s->sh_info = q - new_syms;
|
---|
746 |
|
---|
747 | /* then second pass for non local symbols */
|
---|
748 | p = (ElfW(Sym) *)s->data;
|
---|
749 | for(i = 0; i < nb_syms; i++) {
|
---|
750 | if (ELFW(ST_BIND)(p->st_info) != STB_LOCAL) {
|
---|
751 | old_to_new_syms[i] = q - new_syms;
|
---|
752 | *q++ = *p;
|
---|
753 | }
|
---|
754 | p++;
|
---|
755 | }
|
---|
756 |
|
---|
757 | /* we copy the new symbols to the old */
|
---|
758 | memcpy(s->data, new_syms, nb_syms * sizeof(ElfW(Sym)));
|
---|
759 | tcc_free(new_syms);
|
---|
760 |
|
---|
761 | /* now we modify all the relocations */
|
---|
762 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
763 | sr = s1->sections[i];
|
---|
764 | if (sr->sh_type == SHT_RELX && sr->link == s) {
|
---|
765 | for_each_elem(sr, 0, rel, ElfW_Rel) {
|
---|
766 | sym_index = ELFW(R_SYM)(rel->r_info);
|
---|
767 | type = ELFW(R_TYPE)(rel->r_info);
|
---|
768 | sym_index = old_to_new_syms[sym_index];
|
---|
769 | rel->r_info = ELFW(R_INFO)(sym_index, type);
|
---|
770 | }
|
---|
771 | }
|
---|
772 | }
|
---|
773 |
|
---|
774 | tcc_free(old_to_new_syms);
|
---|
775 | }
|
---|
776 |
|
---|
777 | /* relocate symbol table, resolve undefined symbols if do_resolve is
|
---|
778 | true and output error if undefined symbol. */
|
---|
779 | ST_FUNC void relocate_syms(TCCState *s1, Section *symtab, int do_resolve)
|
---|
780 | {
|
---|
781 | ElfW(Sym) *sym;
|
---|
782 | int sym_bind, sh_num;
|
---|
783 | const char *name;
|
---|
784 |
|
---|
785 | for_each_elem(symtab, 1, sym, ElfW(Sym)) {
|
---|
786 | sh_num = sym->st_shndx;
|
---|
787 | if (sh_num == SHN_UNDEF) {
|
---|
788 | name = (char *) s1->symtab->link->data + sym->st_name;
|
---|
789 | /* Use ld.so to resolve symbol for us (for tcc -run) */
|
---|
790 | if (do_resolve) {
|
---|
791 | #if defined TCC_IS_NATIVE && !defined TCC_TARGET_PE
|
---|
792 | void *addr = dlsym(RTLD_DEFAULT, name);
|
---|
793 | if (addr) {
|
---|
794 | sym->st_value = (addr_t) addr;
|
---|
795 | #ifdef DEBUG_RELOC
|
---|
796 | printf ("relocate_sym: %s -> 0x%lx\n", name, sym->st_value);
|
---|
797 | #endif
|
---|
798 | goto found;
|
---|
799 | }
|
---|
800 | #endif
|
---|
801 | /* if dynamic symbol exist, it will be used in relocate_section */
|
---|
802 | } else if (s1->dynsym && find_elf_sym(s1->dynsym, name))
|
---|
803 | goto found;
|
---|
804 | /* XXX: _fp_hw seems to be part of the ABI, so we ignore
|
---|
805 | it */
|
---|
806 | if (!strcmp(name, "_fp_hw"))
|
---|
807 | goto found;
|
---|
808 | /* only weak symbols are accepted to be undefined. Their
|
---|
809 | value is zero */
|
---|
810 | sym_bind = ELFW(ST_BIND)(sym->st_info);
|
---|
811 | if (sym_bind == STB_WEAK)
|
---|
812 | sym->st_value = 0;
|
---|
813 | else
|
---|
814 | tcc_error_noabort("undefined symbol '%s'", name);
|
---|
815 | } else if (sh_num < SHN_LORESERVE) {
|
---|
816 | /* add section base */
|
---|
817 | sym->st_value += s1->sections[sym->st_shndx]->sh_addr;
|
---|
818 | }
|
---|
819 | found: ;
|
---|
820 | }
|
---|
821 | }
|
---|
822 |
|
---|
823 | /* relocate a given section (CPU dependent) by applying the relocations
|
---|
824 | in the associated relocation section */
|
---|
825 | ST_FUNC void relocate_section(TCCState *s1, Section *s)
|
---|
826 | {
|
---|
827 | Section *sr = s->reloc;
|
---|
828 | ElfW_Rel *rel;
|
---|
829 | ElfW(Sym) *sym;
|
---|
830 | int type, sym_index;
|
---|
831 | unsigned char *ptr;
|
---|
832 | addr_t tgt, addr;
|
---|
833 |
|
---|
834 | relocate_init(sr);
|
---|
835 |
|
---|
836 | for_each_elem(sr, 0, rel, ElfW_Rel) {
|
---|
837 | ptr = s->data + rel->r_offset;
|
---|
838 | sym_index = ELFW(R_SYM)(rel->r_info);
|
---|
839 | sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
|
---|
840 | type = ELFW(R_TYPE)(rel->r_info);
|
---|
841 | tgt = sym->st_value;
|
---|
842 | #if SHT_RELX == SHT_RELA
|
---|
843 | tgt += rel->r_addend;
|
---|
844 | #endif
|
---|
845 | addr = s->sh_addr + rel->r_offset;
|
---|
846 | relocate(s1, rel, type, ptr, addr, tgt);
|
---|
847 | }
|
---|
848 | /* if the relocation is allocated, we change its symbol table */
|
---|
849 | if (sr->sh_flags & SHF_ALLOC)
|
---|
850 | sr->link = s1->dynsym;
|
---|
851 | }
|
---|
852 |
|
---|
853 | /* relocate relocation table in 'sr' */
|
---|
854 | static void relocate_rel(TCCState *s1, Section *sr)
|
---|
855 | {
|
---|
856 | Section *s;
|
---|
857 | ElfW_Rel *rel;
|
---|
858 |
|
---|
859 | s = s1->sections[sr->sh_info];
|
---|
860 | for_each_elem(sr, 0, rel, ElfW_Rel)
|
---|
861 | rel->r_offset += s->sh_addr;
|
---|
862 | }
|
---|
863 |
|
---|
864 | /* count the number of dynamic relocations so that we can reserve
|
---|
865 | their space */
|
---|
866 | static int prepare_dynamic_rel(TCCState *s1, Section *sr)
|
---|
867 | {
|
---|
868 | ElfW_Rel *rel;
|
---|
869 | int sym_index, type, count;
|
---|
870 |
|
---|
871 | count = 0;
|
---|
872 | for_each_elem(sr, 0, rel, ElfW_Rel) {
|
---|
873 | sym_index = ELFW(R_SYM)(rel->r_info);
|
---|
874 | type = ELFW(R_TYPE)(rel->r_info);
|
---|
875 | switch(type) {
|
---|
876 | #if defined(TCC_TARGET_I386)
|
---|
877 | case R_386_32:
|
---|
878 | if (!get_sym_attr(s1, sym_index, 0)->dyn_index
|
---|
879 | && ((ElfW(Sym)*)symtab_section->data + sym_index)->st_shndx == SHN_UNDEF) {
|
---|
880 | /* don't fixup unresolved (weak) symbols */
|
---|
881 | rel->r_info = ELFW(R_INFO)(sym_index, R_386_RELATIVE);
|
---|
882 | break;
|
---|
883 | }
|
---|
884 | #elif defined(TCC_TARGET_X86_64)
|
---|
885 | case R_X86_64_32:
|
---|
886 | case R_X86_64_32S:
|
---|
887 | case R_X86_64_64:
|
---|
888 | #endif
|
---|
889 | count++;
|
---|
890 | break;
|
---|
891 | #if defined(TCC_TARGET_I386)
|
---|
892 | case R_386_PC32:
|
---|
893 | #elif defined(TCC_TARGET_X86_64)
|
---|
894 | case R_X86_64_PC32:
|
---|
895 | #endif
|
---|
896 | if (get_sym_attr(s1, sym_index, 0)->dyn_index)
|
---|
897 | count++;
|
---|
898 | break;
|
---|
899 | default:
|
---|
900 | break;
|
---|
901 | }
|
---|
902 | }
|
---|
903 | if (count) {
|
---|
904 | /* allocate the section */
|
---|
905 | sr->sh_flags |= SHF_ALLOC;
|
---|
906 | sr->sh_size = count * sizeof(ElfW_Rel);
|
---|
907 | }
|
---|
908 | return count;
|
---|
909 | }
|
---|
910 |
|
---|
911 | static void build_got(TCCState *s1)
|
---|
912 | {
|
---|
913 | /* if no got, then create it */
|
---|
914 | s1->got = new_section(s1, ".got", SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
|
---|
915 | s1->got->sh_entsize = 4;
|
---|
916 | set_elf_sym(symtab_section, 0, 4, ELFW(ST_INFO)(STB_GLOBAL, STT_OBJECT),
|
---|
917 | 0, s1->got->sh_num, "_GLOBAL_OFFSET_TABLE_");
|
---|
918 | /* keep space for _DYNAMIC pointer and two dummy got entries */
|
---|
919 | section_ptr_add(s1->got, 3 * PTR_SIZE);
|
---|
920 | }
|
---|
921 |
|
---|
922 | /* Create a GOT and (for function call) a PLT entry corresponding to a symbol
|
---|
923 | in s1->symtab. When creating the dynamic symbol table entry for the GOT
|
---|
924 | relocation, use 'size' and 'info' for the corresponding symbol metadata.
|
---|
925 | Returns the offset of the GOT or (if any) PLT entry. */
|
---|
926 | static struct sym_attr * put_got_entry(TCCState *s1, int dyn_reloc_type,
|
---|
927 | unsigned long size,
|
---|
928 | int info, int sym_index)
|
---|
929 | {
|
---|
930 | int need_plt_entry;
|
---|
931 | const char *name;
|
---|
932 | ElfW(Sym) *sym;
|
---|
933 | struct sym_attr *attr;
|
---|
934 | unsigned got_offset;
|
---|
935 | char plt_name[100];
|
---|
936 | int len;
|
---|
937 |
|
---|
938 | need_plt_entry = (dyn_reloc_type == R_JMP_SLOT);
|
---|
939 | attr = get_sym_attr(s1, sym_index, 1);
|
---|
940 |
|
---|
941 | /* In case a function is both called and its address taken 2 GOT entries
|
---|
942 | are created, one for taking the address (GOT) and the other for the PLT
|
---|
943 | entry (PLTGOT). */
|
---|
944 | if (need_plt_entry ? attr->plt_offset : attr->got_offset)
|
---|
945 | return attr;
|
---|
946 |
|
---|
947 | /* create the GOT entry */
|
---|
948 | got_offset = s1->got->data_offset;
|
---|
949 | section_ptr_add(s1->got, PTR_SIZE);
|
---|
950 |
|
---|
951 | /* Create the GOT relocation that will insert the address of the object or
|
---|
952 | function of interest in the GOT entry. This is a static relocation for
|
---|
953 | memory output (dlsym will give us the address of symbols) and dynamic
|
---|
954 | relocation otherwise (executable and DLLs). The relocation should be
|
---|
955 | done lazily for GOT entry with *_JUMP_SLOT relocation type (the one
|
---|
956 | associated to a PLT entry) but is currently done at load time for an
|
---|
957 | unknown reason. */
|
---|
958 |
|
---|
959 | sym = &((ElfW(Sym) *) symtab_section->data)[sym_index];
|
---|
960 | name = (char *) symtab_section->link->data + sym->st_name;
|
---|
961 |
|
---|
962 | if (s1->dynsym) {
|
---|
963 | if (ELFW(ST_BIND)(sym->st_info) == STB_LOCAL) {
|
---|
964 | /* Hack alarm. We don't want to emit dynamic symbols
|
---|
965 | and symbol based relocs for STB_LOCAL symbols, but rather
|
---|
966 | want to resolve them directly. At this point the symbol
|
---|
967 | values aren't final yet, so we must defer this. We will later
|
---|
968 | have to create a RELATIVE reloc anyway, so we misuse the
|
---|
969 | relocation slot to smuggle the symbol reference until
|
---|
970 | fill_local_got_entries. Not that the sym_index is
|
---|
971 | relative to symtab_section, not s1->dynsym! Nevertheless
|
---|
972 | we use s1->dyn_sym so that if this is the first call
|
---|
973 | that got->reloc is correctly created. Also note that
|
---|
974 | RELATIVE relocs are not normally created for the .got,
|
---|
975 | so the types serves as a marker for later (and is retained
|
---|
976 | also for the final output, which is okay because then the
|
---|
977 | got is just normal data). */
|
---|
978 | put_elf_reloc(s1->dynsym, s1->got, got_offset, R_RELATIVE,
|
---|
979 | sym_index);
|
---|
980 | } else {
|
---|
981 | if (0 == attr->dyn_index)
|
---|
982 | attr->dyn_index = set_elf_sym(s1->dynsym, sym->st_value, size,
|
---|
983 | info, 0, sym->st_shndx, name);
|
---|
984 | put_elf_reloc(s1->dynsym, s1->got, got_offset, dyn_reloc_type,
|
---|
985 | attr->dyn_index);
|
---|
986 | }
|
---|
987 | } else {
|
---|
988 | put_elf_reloc(symtab_section, s1->got, got_offset, dyn_reloc_type,
|
---|
989 | sym_index);
|
---|
990 | }
|
---|
991 |
|
---|
992 | if (need_plt_entry) {
|
---|
993 | if (!s1->plt) {
|
---|
994 | s1->plt = new_section(s1, ".plt", SHT_PROGBITS,
|
---|
995 | SHF_ALLOC | SHF_EXECINSTR);
|
---|
996 | s1->plt->sh_entsize = 4;
|
---|
997 | }
|
---|
998 |
|
---|
999 | attr->plt_offset = create_plt_entry(s1, got_offset, attr);
|
---|
1000 |
|
---|
1001 | /* create a symbol 'sym@plt' for the PLT jump vector */
|
---|
1002 | len = strlen(name);
|
---|
1003 | if (len > sizeof plt_name - 5)
|
---|
1004 | len = sizeof plt_name - 5;
|
---|
1005 | memcpy(plt_name, name, len);
|
---|
1006 | strcpy(plt_name + len, "@plt");
|
---|
1007 | attr->plt_sym = put_elf_sym(s1->symtab, attr->plt_offset, sym->st_size,
|
---|
1008 | ELFW(ST_INFO)(STB_GLOBAL, STT_FUNC), 0, s1->plt->sh_num, plt_name);
|
---|
1009 |
|
---|
1010 | } else {
|
---|
1011 | attr->got_offset = got_offset;
|
---|
1012 | }
|
---|
1013 |
|
---|
1014 | return attr;
|
---|
1015 | }
|
---|
1016 |
|
---|
1017 | /* build GOT and PLT entries */
|
---|
1018 | ST_FUNC void build_got_entries(TCCState *s1)
|
---|
1019 | {
|
---|
1020 | Section *s;
|
---|
1021 | ElfW_Rel *rel;
|
---|
1022 | ElfW(Sym) *sym;
|
---|
1023 | int i, type, gotplt_entry, reloc_type, sym_index;
|
---|
1024 | struct sym_attr *attr;
|
---|
1025 |
|
---|
1026 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
1027 | s = s1->sections[i];
|
---|
1028 | if (s->sh_type != SHT_RELX)
|
---|
1029 | continue;
|
---|
1030 | /* no need to handle got relocations */
|
---|
1031 | if (s->link != symtab_section)
|
---|
1032 | continue;
|
---|
1033 | for_each_elem(s, 0, rel, ElfW_Rel) {
|
---|
1034 | type = ELFW(R_TYPE)(rel->r_info);
|
---|
1035 | gotplt_entry = gotplt_entry_type(type);
|
---|
1036 | sym_index = ELFW(R_SYM)(rel->r_info);
|
---|
1037 | sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
|
---|
1038 |
|
---|
1039 | if (gotplt_entry == NO_GOTPLT_ENTRY) {
|
---|
1040 | continue;
|
---|
1041 | }
|
---|
1042 |
|
---|
1043 | /* Automatically create PLT/GOT [entry] if it is an undefined
|
---|
1044 | reference (resolved at runtime), or the symbol is absolute,
|
---|
1045 | probably created by tcc_add_symbol, and thus on 64-bit
|
---|
1046 | targets might be too far from application code. */
|
---|
1047 | if (gotplt_entry == AUTO_GOTPLT_ENTRY) {
|
---|
1048 | if (sym->st_shndx == SHN_UNDEF) {
|
---|
1049 | ElfW(Sym) *esym;
|
---|
1050 | int dynindex;
|
---|
1051 | if (s1->output_type == TCC_OUTPUT_DLL && ! PCRELATIVE_DLLPLT)
|
---|
1052 | continue;
|
---|
1053 | /* Relocations for UNDEF symbols would normally need
|
---|
1054 | to be transferred into the executable or shared object.
|
---|
1055 | If that were done AUTO_GOTPLT_ENTRY wouldn't exist.
|
---|
1056 | But TCC doesn't do that (at least for exes), so we
|
---|
1057 | need to resolve all such relocs locally. And that
|
---|
1058 | means PLT slots for functions in DLLs and COPY relocs for
|
---|
1059 | data symbols. COPY relocs were generated in
|
---|
1060 | bind_exe_dynsyms (and the symbol adjusted to be defined),
|
---|
1061 | and for functions we were generated a dynamic symbol
|
---|
1062 | of function type. */
|
---|
1063 | if (s1->dynsym) {
|
---|
1064 | /* dynsym isn't set for -run :-/ */
|
---|
1065 | dynindex = get_sym_attr(s1, sym_index, 0)->dyn_index;
|
---|
1066 | esym = (ElfW(Sym) *)s1->dynsym->data + dynindex;
|
---|
1067 | if (dynindex
|
---|
1068 | && (ELFW(ST_TYPE)(esym->st_info) == STT_FUNC
|
---|
1069 | || (ELFW(ST_TYPE)(esym->st_info) == STT_NOTYPE
|
---|
1070 | && ELFW(ST_TYPE)(sym->st_info) == STT_FUNC)))
|
---|
1071 | goto jmp_slot;
|
---|
1072 | }
|
---|
1073 | } else if (!(sym->st_shndx == SHN_ABS
|
---|
1074 | #ifndef TCC_TARGET_ARM
|
---|
1075 | && PTR_SIZE == 8
|
---|
1076 | #endif
|
---|
1077 | ))
|
---|
1078 | continue;
|
---|
1079 | }
|
---|
1080 |
|
---|
1081 | #ifdef TCC_TARGET_X86_64
|
---|
1082 | if ((type == R_X86_64_PLT32 || type == R_X86_64_PC32) &&
|
---|
1083 | (ELFW(ST_VISIBILITY)(sym->st_other) != STV_DEFAULT ||
|
---|
1084 | ELFW(ST_BIND)(sym->st_info) == STB_LOCAL)) {
|
---|
1085 | rel->r_info = ELFW(R_INFO)(sym_index, R_X86_64_PC32);
|
---|
1086 | continue;
|
---|
1087 | }
|
---|
1088 | #endif
|
---|
1089 | if (code_reloc(type)) {
|
---|
1090 | jmp_slot:
|
---|
1091 | reloc_type = R_JMP_SLOT;
|
---|
1092 | } else
|
---|
1093 | reloc_type = R_GLOB_DAT;
|
---|
1094 |
|
---|
1095 | if (!s1->got)
|
---|
1096 | build_got(s1);
|
---|
1097 |
|
---|
1098 | if (gotplt_entry == BUILD_GOT_ONLY)
|
---|
1099 | continue;
|
---|
1100 |
|
---|
1101 | attr = put_got_entry(s1, reloc_type, sym->st_size, sym->st_info,
|
---|
1102 | sym_index);
|
---|
1103 |
|
---|
1104 | if (reloc_type == R_JMP_SLOT)
|
---|
1105 | rel->r_info = ELFW(R_INFO)(attr->plt_sym, type);
|
---|
1106 | }
|
---|
1107 | }
|
---|
1108 | }
|
---|
1109 |
|
---|
1110 | /* put dynamic tag */
|
---|
1111 | static void put_dt(Section *dynamic, int dt, addr_t val)
|
---|
1112 | {
|
---|
1113 | ElfW(Dyn) *dyn;
|
---|
1114 | dyn = section_ptr_add(dynamic, sizeof(ElfW(Dyn)));
|
---|
1115 | dyn->d_tag = dt;
|
---|
1116 | dyn->d_un.d_val = val;
|
---|
1117 | }
|
---|
1118 |
|
---|
1119 | #ifndef TCC_TARGET_PE
|
---|
1120 | static void add_init_array_defines(TCCState *s1, const char *section_name)
|
---|
1121 | {
|
---|
1122 | Section *s;
|
---|
1123 | long end_offset;
|
---|
1124 | char sym_start[1024];
|
---|
1125 | char sym_end[1024];
|
---|
1126 |
|
---|
1127 | snprintf(sym_start, sizeof(sym_start), "__%s_start", section_name + 1);
|
---|
1128 | snprintf(sym_end, sizeof(sym_end), "__%s_end", section_name + 1);
|
---|
1129 |
|
---|
1130 | s = find_section(s1, section_name);
|
---|
1131 | if (!s) {
|
---|
1132 | end_offset = 0;
|
---|
1133 | s = data_section;
|
---|
1134 | } else {
|
---|
1135 | end_offset = s->data_offset;
|
---|
1136 | }
|
---|
1137 |
|
---|
1138 | set_elf_sym(symtab_section,
|
---|
1139 | 0, 0,
|
---|
1140 | ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
|
---|
1141 | s->sh_num, sym_start);
|
---|
1142 | set_elf_sym(symtab_section,
|
---|
1143 | end_offset, 0,
|
---|
1144 | ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
|
---|
1145 | s->sh_num, sym_end);
|
---|
1146 | }
|
---|
1147 | #endif
|
---|
1148 |
|
---|
1149 | static int tcc_add_support(TCCState *s1, const char *filename)
|
---|
1150 | {
|
---|
1151 | char buf[1024];
|
---|
1152 | snprintf(buf, sizeof(buf), "%s/%s", s1->tcc_lib_path, filename);
|
---|
1153 | return tcc_add_file(s1, buf);
|
---|
1154 | }
|
---|
1155 |
|
---|
1156 | ST_FUNC void tcc_add_bcheck(TCCState *s1)
|
---|
1157 | {
|
---|
1158 | #ifdef CONFIG_TCC_BCHECK
|
---|
1159 | addr_t *ptr;
|
---|
1160 | int sym_index;
|
---|
1161 |
|
---|
1162 | if (0 == s1->do_bounds_check)
|
---|
1163 | return;
|
---|
1164 | /* XXX: add an object file to do that */
|
---|
1165 | ptr = section_ptr_add(bounds_section, sizeof(*ptr));
|
---|
1166 | *ptr = 0;
|
---|
1167 | set_elf_sym(symtab_section, 0, 0,
|
---|
1168 | ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
|
---|
1169 | bounds_section->sh_num, "__bounds_start");
|
---|
1170 | /* pull bcheck.o from libtcc1.a */
|
---|
1171 | sym_index = set_elf_sym(symtab_section, 0, 0,
|
---|
1172 | ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
|
---|
1173 | SHN_UNDEF, "__bound_init");
|
---|
1174 | if (s1->output_type != TCC_OUTPUT_MEMORY) {
|
---|
1175 | /* add 'call __bound_init()' in .init section */
|
---|
1176 | Section *init_section = find_section(s1, ".init");
|
---|
1177 | unsigned char *pinit = section_ptr_add(init_section, 5);
|
---|
1178 | pinit[0] = 0xe8;
|
---|
1179 | write32le(pinit + 1, -4);
|
---|
1180 | put_elf_reloc(symtab_section, init_section,
|
---|
1181 | init_section->data_offset - 4, R_386_PC32, sym_index);
|
---|
1182 | /* R_386_PC32 = R_X86_64_PC32 = 2 */
|
---|
1183 | }
|
---|
1184 | #endif
|
---|
1185 | }
|
---|
1186 |
|
---|
1187 | /* add tcc runtime libraries */
|
---|
1188 | ST_FUNC void tcc_add_runtime(TCCState *s1)
|
---|
1189 | {
|
---|
1190 | tcc_add_bcheck(s1);
|
---|
1191 | tcc_add_pragma_libs(s1);
|
---|
1192 | /* add libc */
|
---|
1193 | if (!s1->nostdlib) {
|
---|
1194 | tcc_add_library_err(s1, "c");
|
---|
1195 | #ifdef TCC_LIBGCC
|
---|
1196 | if (!s1->static_link) {
|
---|
1197 | if (TCC_LIBGCC[0] == '/')
|
---|
1198 | tcc_add_file(s1, TCC_LIBGCC);
|
---|
1199 | else
|
---|
1200 | tcc_add_dll(s1, TCC_LIBGCC, 0);
|
---|
1201 | }
|
---|
1202 | #endif
|
---|
1203 | tcc_add_support(s1, TCC_LIBTCC1);
|
---|
1204 | /* add crt end if not memory output */
|
---|
1205 | if (s1->output_type != TCC_OUTPUT_MEMORY)
|
---|
1206 | tcc_add_crt(s1, "crtn.o");
|
---|
1207 | }
|
---|
1208 | }
|
---|
1209 |
|
---|
1210 | /* add various standard linker symbols (must be done after the
|
---|
1211 | sections are filled (for example after allocating common
|
---|
1212 | symbols)) */
|
---|
1213 | static void tcc_add_linker_symbols(TCCState *s1)
|
---|
1214 | {
|
---|
1215 | char buf[1024];
|
---|
1216 | int i;
|
---|
1217 | Section *s;
|
---|
1218 |
|
---|
1219 | set_elf_sym(symtab_section,
|
---|
1220 | text_section->data_offset, 0,
|
---|
1221 | ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
|
---|
1222 | text_section->sh_num, "_etext");
|
---|
1223 | set_elf_sym(symtab_section,
|
---|
1224 | data_section->data_offset, 0,
|
---|
1225 | ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
|
---|
1226 | data_section->sh_num, "_edata");
|
---|
1227 | set_elf_sym(symtab_section,
|
---|
1228 | bss_section->data_offset, 0,
|
---|
1229 | ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
|
---|
1230 | bss_section->sh_num, "_end");
|
---|
1231 | #ifndef TCC_TARGET_PE
|
---|
1232 | /* horrible new standard ldscript defines */
|
---|
1233 | add_init_array_defines(s1, ".preinit_array");
|
---|
1234 | add_init_array_defines(s1, ".init_array");
|
---|
1235 | add_init_array_defines(s1, ".fini_array");
|
---|
1236 | #endif
|
---|
1237 |
|
---|
1238 | /* add start and stop symbols for sections whose name can be
|
---|
1239 | expressed in C */
|
---|
1240 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
1241 | s = s1->sections[i];
|
---|
1242 | if (s->sh_type == SHT_PROGBITS &&
|
---|
1243 | (s->sh_flags & SHF_ALLOC)) {
|
---|
1244 | const char *p;
|
---|
1245 | int ch;
|
---|
1246 |
|
---|
1247 | /* check if section name can be expressed in C */
|
---|
1248 | p = s->name;
|
---|
1249 | for(;;) {
|
---|
1250 | ch = *p;
|
---|
1251 | if (!ch)
|
---|
1252 | break;
|
---|
1253 | if (!isid(ch) && !isnum(ch))
|
---|
1254 | goto next_sec;
|
---|
1255 | p++;
|
---|
1256 | }
|
---|
1257 | snprintf(buf, sizeof(buf), "__start_%s", s->name);
|
---|
1258 | set_elf_sym(symtab_section,
|
---|
1259 | 0, 0,
|
---|
1260 | ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
|
---|
1261 | s->sh_num, buf);
|
---|
1262 | snprintf(buf, sizeof(buf), "__stop_%s", s->name);
|
---|
1263 | set_elf_sym(symtab_section,
|
---|
1264 | s->data_offset, 0,
|
---|
1265 | ELFW(ST_INFO)(STB_GLOBAL, STT_NOTYPE), 0,
|
---|
1266 | s->sh_num, buf);
|
---|
1267 | }
|
---|
1268 | next_sec: ;
|
---|
1269 | }
|
---|
1270 | }
|
---|
1271 |
|
---|
1272 | ST_FUNC void resolve_common_syms(TCCState *s1)
|
---|
1273 | {
|
---|
1274 | ElfW(Sym) *sym;
|
---|
1275 |
|
---|
1276 | /* Allocate common symbols in BSS. */
|
---|
1277 | for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
|
---|
1278 | if (sym->st_shndx == SHN_COMMON) {
|
---|
1279 | /* symbol alignment is in st_value for SHN_COMMONs */
|
---|
1280 | sym->st_value = section_add(bss_section, sym->st_size,
|
---|
1281 | sym->st_value);
|
---|
1282 | sym->st_shndx = bss_section->sh_num;
|
---|
1283 | }
|
---|
1284 | }
|
---|
1285 |
|
---|
1286 | /* Now assign linker provided symbols their value. */
|
---|
1287 | tcc_add_linker_symbols(s1);
|
---|
1288 | }
|
---|
1289 |
|
---|
1290 | static void tcc_output_binary(TCCState *s1, FILE *f,
|
---|
1291 | const int *sec_order)
|
---|
1292 | {
|
---|
1293 | Section *s;
|
---|
1294 | int i, offset, size;
|
---|
1295 |
|
---|
1296 | offset = 0;
|
---|
1297 | for(i=1;i<s1->nb_sections;i++) {
|
---|
1298 | s = s1->sections[sec_order[i]];
|
---|
1299 | if (s->sh_type != SHT_NOBITS &&
|
---|
1300 | (s->sh_flags & SHF_ALLOC)) {
|
---|
1301 | while (offset < s->sh_offset) {
|
---|
1302 | fputc(0, f);
|
---|
1303 | offset++;
|
---|
1304 | }
|
---|
1305 | size = s->sh_size;
|
---|
1306 | fwrite(s->data, 1, size, f);
|
---|
1307 | offset += size;
|
---|
1308 | }
|
---|
1309 | }
|
---|
1310 | }
|
---|
1311 |
|
---|
1312 | ST_FUNC void fill_got_entry(TCCState *s1, ElfW_Rel *rel)
|
---|
1313 | {
|
---|
1314 | int sym_index = ELFW(R_SYM) (rel->r_info);
|
---|
1315 | ElfW(Sym) *sym = &((ElfW(Sym) *) symtab_section->data)[sym_index];
|
---|
1316 | struct sym_attr *attr = get_sym_attr(s1, sym_index, 0);
|
---|
1317 | unsigned offset = attr->got_offset;
|
---|
1318 |
|
---|
1319 | if (0 == offset)
|
---|
1320 | return;
|
---|
1321 | section_reserve(s1->got, offset + PTR_SIZE);
|
---|
1322 | #ifdef TCC_TARGET_X86_64
|
---|
1323 | write64le(s1->got->data + offset, sym->st_value);
|
---|
1324 | #else
|
---|
1325 | write32le(s1->got->data + offset, sym->st_value);
|
---|
1326 | #endif
|
---|
1327 | }
|
---|
1328 |
|
---|
1329 | /* Perform relocation to GOT or PLT entries */
|
---|
1330 | ST_FUNC void fill_got(TCCState *s1)
|
---|
1331 | {
|
---|
1332 | Section *s;
|
---|
1333 | ElfW_Rel *rel;
|
---|
1334 | int i;
|
---|
1335 |
|
---|
1336 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
1337 | s = s1->sections[i];
|
---|
1338 | if (s->sh_type != SHT_RELX)
|
---|
1339 | continue;
|
---|
1340 | /* no need to handle got relocations */
|
---|
1341 | if (s->link != symtab_section)
|
---|
1342 | continue;
|
---|
1343 | for_each_elem(s, 0, rel, ElfW_Rel) {
|
---|
1344 | switch (ELFW(R_TYPE) (rel->r_info)) {
|
---|
1345 | case R_X86_64_GOT32:
|
---|
1346 | case R_X86_64_GOTPCREL:
|
---|
1347 | case R_X86_64_GOTPCRELX:
|
---|
1348 | case R_X86_64_REX_GOTPCRELX:
|
---|
1349 | case R_X86_64_PLT32:
|
---|
1350 | fill_got_entry(s1, rel);
|
---|
1351 | break;
|
---|
1352 | }
|
---|
1353 | }
|
---|
1354 | }
|
---|
1355 | }
|
---|
1356 |
|
---|
1357 | /* See put_got_entry for a description. This is the second stage
|
---|
1358 | where GOT references to local defined symbols are rewritten. */
|
---|
1359 | static void fill_local_got_entries(TCCState *s1)
|
---|
1360 | {
|
---|
1361 | ElfW_Rel *rel;
|
---|
1362 | for_each_elem(s1->got->reloc, 0, rel, ElfW_Rel) {
|
---|
1363 | if (ELFW(R_TYPE)(rel->r_info) == R_RELATIVE) {
|
---|
1364 | int sym_index = ELFW(R_SYM) (rel->r_info);
|
---|
1365 | ElfW(Sym) *sym = &((ElfW(Sym) *) symtab_section->data)[sym_index];
|
---|
1366 | struct sym_attr *attr = get_sym_attr(s1, sym_index, 0);
|
---|
1367 | unsigned offset = attr->got_offset;
|
---|
1368 | if (offset != rel->r_offset - s1->got->sh_addr)
|
---|
1369 | tcc_error_noabort("huh");
|
---|
1370 | rel->r_info = ELFW(R_INFO)(0, R_RELATIVE);
|
---|
1371 | #if SHT_RELX == SHT_RELA
|
---|
1372 | rel->r_addend = sym->st_value;
|
---|
1373 | #else
|
---|
1374 | /* All our REL architectures also happen to be 32bit LE. */
|
---|
1375 | write32le(s1->got->data + offset, sym->st_value);
|
---|
1376 | #endif
|
---|
1377 | }
|
---|
1378 | }
|
---|
1379 | }
|
---|
1380 |
|
---|
1381 | /* Bind symbols of executable: resolve undefined symbols from exported symbols
|
---|
1382 | in shared libraries and export non local defined symbols to shared libraries
|
---|
1383 | if -rdynamic switch was given on command line */
|
---|
1384 | static void bind_exe_dynsyms(TCCState *s1)
|
---|
1385 | {
|
---|
1386 | const char *name;
|
---|
1387 | int sym_index, index;
|
---|
1388 | ElfW(Sym) *sym, *esym;
|
---|
1389 | int type;
|
---|
1390 |
|
---|
1391 | /* Resolve undefined symbols from dynamic symbols. When there is a match:
|
---|
1392 | - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
|
---|
1393 | - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
|
---|
1394 | for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
|
---|
1395 | if (sym->st_shndx == SHN_UNDEF) {
|
---|
1396 | name = (char *) symtab_section->link->data + sym->st_name;
|
---|
1397 | sym_index = find_elf_sym(s1->dynsymtab_section, name);
|
---|
1398 | if (sym_index) {
|
---|
1399 | esym = &((ElfW(Sym) *)s1->dynsymtab_section->data)[sym_index];
|
---|
1400 | type = ELFW(ST_TYPE)(esym->st_info);
|
---|
1401 | if ((type == STT_FUNC) || (type == STT_GNU_IFUNC)) {
|
---|
1402 | /* Indirect functions shall have STT_FUNC type in executable
|
---|
1403 | * dynsym section. Indeed, a dlsym call following a lazy
|
---|
1404 | * resolution would pick the symbol value from the
|
---|
1405 | * executable dynsym entry which would contain the address
|
---|
1406 | * of the function wanted by the caller of dlsym instead of
|
---|
1407 | * the address of the function that would return that
|
---|
1408 | * address */
|
---|
1409 | int dynindex
|
---|
1410 | = put_elf_sym(s1->dynsym, 0, esym->st_size,
|
---|
1411 | ELFW(ST_INFO)(STB_GLOBAL,STT_FUNC), 0, 0,
|
---|
1412 | name);
|
---|
1413 | int index = sym - (ElfW(Sym) *) symtab_section->data;
|
---|
1414 | get_sym_attr(s1, index, 1)->dyn_index = dynindex;
|
---|
1415 | } else if (type == STT_OBJECT) {
|
---|
1416 | unsigned long offset;
|
---|
1417 | ElfW(Sym) *dynsym;
|
---|
1418 | offset = bss_section->data_offset;
|
---|
1419 | /* XXX: which alignment ? */
|
---|
1420 | offset = (offset + 16 - 1) & -16;
|
---|
1421 | set_elf_sym (s1->symtab, offset, esym->st_size,
|
---|
1422 | esym->st_info, 0, bss_section->sh_num, name);
|
---|
1423 | index = put_elf_sym(s1->dynsym, offset, esym->st_size,
|
---|
1424 | esym->st_info, 0, bss_section->sh_num,
|
---|
1425 | name);
|
---|
1426 |
|
---|
1427 | /* Ensure R_COPY works for weak symbol aliases */
|
---|
1428 | if (ELFW(ST_BIND)(esym->st_info) == STB_WEAK) {
|
---|
1429 | for_each_elem(s1->dynsymtab_section, 1, dynsym, ElfW(Sym)) {
|
---|
1430 | if ((dynsym->st_value == esym->st_value)
|
---|
1431 | && (ELFW(ST_BIND)(dynsym->st_info) == STB_GLOBAL)) {
|
---|
1432 | char *dynname = (char *) s1->dynsymtab_section->link->data
|
---|
1433 | + dynsym->st_name;
|
---|
1434 | put_elf_sym(s1->dynsym, offset, dynsym->st_size,
|
---|
1435 | dynsym->st_info, 0,
|
---|
1436 | bss_section->sh_num, dynname);
|
---|
1437 | break;
|
---|
1438 | }
|
---|
1439 | }
|
---|
1440 | }
|
---|
1441 |
|
---|
1442 | put_elf_reloc(s1->dynsym, bss_section,
|
---|
1443 | offset, R_COPY, index);
|
---|
1444 | offset += esym->st_size;
|
---|
1445 | bss_section->data_offset = offset;
|
---|
1446 | }
|
---|
1447 | } else {
|
---|
1448 | /* STB_WEAK undefined symbols are accepted */
|
---|
1449 | /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
|
---|
1450 | if (ELFW(ST_BIND)(sym->st_info) == STB_WEAK ||
|
---|
1451 | !strcmp(name, "_fp_hw")) {
|
---|
1452 | } else {
|
---|
1453 | tcc_error_noabort("undefined symbol '%s'", name);
|
---|
1454 | }
|
---|
1455 | }
|
---|
1456 | } else if (s1->rdynamic && ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
|
---|
1457 | /* if -rdynamic option, then export all non local symbols */
|
---|
1458 | name = (char *) symtab_section->link->data + sym->st_name;
|
---|
1459 | set_elf_sym(s1->dynsym, sym->st_value, sym->st_size, sym->st_info,
|
---|
1460 | 0, sym->st_shndx, name);
|
---|
1461 | }
|
---|
1462 | }
|
---|
1463 | }
|
---|
1464 |
|
---|
1465 | /* Bind symbols of libraries: export all non local symbols of executable that
|
---|
1466 | are referenced by shared libraries. The reason is that the dynamic loader
|
---|
1467 | search symbol first in executable and then in libraries. Therefore a
|
---|
1468 | reference to a symbol already defined by a library can still be resolved by
|
---|
1469 | a symbol in the executable. */
|
---|
1470 | static void bind_libs_dynsyms(TCCState *s1)
|
---|
1471 | {
|
---|
1472 | const char *name;
|
---|
1473 | int sym_index;
|
---|
1474 | ElfW(Sym) *sym, *esym;
|
---|
1475 |
|
---|
1476 | for_each_elem(s1->dynsymtab_section, 1, esym, ElfW(Sym)) {
|
---|
1477 | name = (char *) s1->dynsymtab_section->link->data + esym->st_name;
|
---|
1478 | sym_index = find_elf_sym(symtab_section, name);
|
---|
1479 | sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
|
---|
1480 | if (sym_index && sym->st_shndx != SHN_UNDEF
|
---|
1481 | && ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
|
---|
1482 | set_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
|
---|
1483 | sym->st_info, 0, sym->st_shndx, name);
|
---|
1484 | } else if (esym->st_shndx == SHN_UNDEF) {
|
---|
1485 | /* weak symbols can stay undefined */
|
---|
1486 | if (ELFW(ST_BIND)(esym->st_info) != STB_WEAK)
|
---|
1487 | tcc_warning("undefined dynamic symbol '%s'", name);
|
---|
1488 | }
|
---|
1489 | }
|
---|
1490 | }
|
---|
1491 |
|
---|
1492 | /* Export all non local symbols. This is used by shared libraries so that the
|
---|
1493 | non local symbols they define can resolve a reference in another shared
|
---|
1494 | library or in the executable. Correspondingly, it allows undefined local
|
---|
1495 | symbols to be resolved by other shared libraries or by the executable. */
|
---|
1496 | static void export_global_syms(TCCState *s1)
|
---|
1497 | {
|
---|
1498 | int dynindex, index;
|
---|
1499 | const char *name;
|
---|
1500 | ElfW(Sym) *sym;
|
---|
1501 |
|
---|
1502 | for_each_elem(symtab_section, 1, sym, ElfW(Sym)) {
|
---|
1503 | if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
|
---|
1504 | name = (char *) symtab_section->link->data + sym->st_name;
|
---|
1505 | dynindex = put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
|
---|
1506 | sym->st_info, 0, sym->st_shndx, name);
|
---|
1507 | index = sym - (ElfW(Sym) *) symtab_section->data;
|
---|
1508 | get_sym_attr(s1, index, 1)->dyn_index = dynindex;
|
---|
1509 | }
|
---|
1510 | }
|
---|
1511 | }
|
---|
1512 |
|
---|
1513 | /* Allocate strings for section names and decide if an unallocated section
|
---|
1514 | should be output.
|
---|
1515 | NOTE: the strsec section comes last, so its size is also correct ! */
|
---|
1516 | static int alloc_sec_names(TCCState *s1, int file_type, Section *strsec)
|
---|
1517 | {
|
---|
1518 | int i;
|
---|
1519 | Section *s;
|
---|
1520 | int textrel = 0;
|
---|
1521 |
|
---|
1522 | /* Allocate strings for section names */
|
---|
1523 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
1524 | s = s1->sections[i];
|
---|
1525 | /* when generating a DLL, we include relocations but we may
|
---|
1526 | patch them */
|
---|
1527 | if (file_type == TCC_OUTPUT_DLL &&
|
---|
1528 | s->sh_type == SHT_RELX &&
|
---|
1529 | !(s->sh_flags & SHF_ALLOC) &&
|
---|
1530 | (s1->sections[s->sh_info]->sh_flags & SHF_ALLOC) &&
|
---|
1531 | prepare_dynamic_rel(s1, s)) {
|
---|
1532 | if (s1->sections[s->sh_info]->sh_flags & SHF_EXECINSTR)
|
---|
1533 | textrel = 1;
|
---|
1534 | } else if (s1->do_debug ||
|
---|
1535 | file_type == TCC_OUTPUT_OBJ ||
|
---|
1536 | (s->sh_flags & SHF_ALLOC) ||
|
---|
1537 | i == (s1->nb_sections - 1)) {
|
---|
1538 | /* we output all sections if debug or object file */
|
---|
1539 | s->sh_size = s->data_offset;
|
---|
1540 | }
|
---|
1541 | if (s->sh_size || (s->sh_flags & SHF_ALLOC))
|
---|
1542 | s->sh_name = put_elf_str(strsec, s->name);
|
---|
1543 | }
|
---|
1544 | strsec->sh_size = strsec->data_offset;
|
---|
1545 | return textrel;
|
---|
1546 | }
|
---|
1547 |
|
---|
1548 | /* Info to be copied in dynamic section */
|
---|
1549 | struct dyn_inf {
|
---|
1550 | Section *dynamic;
|
---|
1551 | Section *dynstr;
|
---|
1552 | unsigned long data_offset;
|
---|
1553 | addr_t rel_addr;
|
---|
1554 | addr_t rel_size;
|
---|
1555 | #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
|
---|
1556 | addr_t bss_addr;
|
---|
1557 | addr_t bss_size;
|
---|
1558 | #endif
|
---|
1559 | };
|
---|
1560 |
|
---|
1561 | /* Assign sections to segments and decide how are sections laid out when loaded
|
---|
1562 | in memory. This function also fills corresponding program headers. */
|
---|
1563 | static int layout_sections(TCCState *s1, ElfW(Phdr) *phdr, int phnum,
|
---|
1564 | Section *interp, Section* strsec,
|
---|
1565 | struct dyn_inf *dyninf, int *sec_order)
|
---|
1566 | {
|
---|
1567 | int i, j, k, file_type, sh_order_index, file_offset;
|
---|
1568 | unsigned long s_align;
|
---|
1569 | long long tmp;
|
---|
1570 | addr_t addr;
|
---|
1571 | ElfW(Phdr) *ph;
|
---|
1572 | Section *s;
|
---|
1573 |
|
---|
1574 | file_type = s1->output_type;
|
---|
1575 | sh_order_index = 1;
|
---|
1576 | file_offset = 0;
|
---|
1577 | if (s1->output_format == TCC_OUTPUT_FORMAT_ELF)
|
---|
1578 | file_offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
|
---|
1579 | s_align = ELF_PAGE_SIZE;
|
---|
1580 | if (s1->section_align)
|
---|
1581 | s_align = s1->section_align;
|
---|
1582 |
|
---|
1583 | if (phnum > 0) {
|
---|
1584 | if (s1->has_text_addr) {
|
---|
1585 | int a_offset, p_offset;
|
---|
1586 | addr = s1->text_addr;
|
---|
1587 | /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
|
---|
1588 | ELF_PAGE_SIZE */
|
---|
1589 | a_offset = (int) (addr & (s_align - 1));
|
---|
1590 | p_offset = file_offset & (s_align - 1);
|
---|
1591 | if (a_offset < p_offset)
|
---|
1592 | a_offset += s_align;
|
---|
1593 | file_offset += (a_offset - p_offset);
|
---|
1594 | } else {
|
---|
1595 | if (file_type == TCC_OUTPUT_DLL)
|
---|
1596 | addr = 0;
|
---|
1597 | else
|
---|
1598 | addr = ELF_START_ADDR;
|
---|
1599 | /* compute address after headers */
|
---|
1600 | addr += (file_offset & (s_align - 1));
|
---|
1601 | }
|
---|
1602 |
|
---|
1603 | ph = &phdr[0];
|
---|
1604 | /* Leave one program headers for the program interpreter and one for
|
---|
1605 | the program header table itself if needed. These are done later as
|
---|
1606 | they require section layout to be done first. */
|
---|
1607 | if (interp)
|
---|
1608 | ph += 2;
|
---|
1609 |
|
---|
1610 | /* dynamic relocation table information, for .dynamic section */
|
---|
1611 | dyninf->rel_addr = dyninf->rel_size = 0;
|
---|
1612 | #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
|
---|
1613 | dyninf->bss_addr = dyninf->bss_size = 0;
|
---|
1614 | #endif
|
---|
1615 |
|
---|
1616 | for(j = 0; j < 2; j++) {
|
---|
1617 | ph->p_type = PT_LOAD;
|
---|
1618 | if (j == 0)
|
---|
1619 | ph->p_flags = PF_R | PF_X;
|
---|
1620 | else
|
---|
1621 | ph->p_flags = PF_R | PF_W;
|
---|
1622 | ph->p_align = s_align;
|
---|
1623 |
|
---|
1624 | /* Decide the layout of sections loaded in memory. This must
|
---|
1625 | be done before program headers are filled since they contain
|
---|
1626 | info about the layout. We do the following ordering: interp,
|
---|
1627 | symbol tables, relocations, progbits, nobits */
|
---|
1628 | /* XXX: do faster and simpler sorting */
|
---|
1629 | for(k = 0; k < 5; k++) {
|
---|
1630 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
1631 | s = s1->sections[i];
|
---|
1632 | /* compute if section should be included */
|
---|
1633 | if (j == 0) {
|
---|
1634 | if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
|
---|
1635 | SHF_ALLOC)
|
---|
1636 | continue;
|
---|
1637 | } else {
|
---|
1638 | if ((s->sh_flags & (SHF_ALLOC | SHF_WRITE)) !=
|
---|
1639 | (SHF_ALLOC | SHF_WRITE))
|
---|
1640 | continue;
|
---|
1641 | }
|
---|
1642 | if (s == interp) {
|
---|
1643 | if (k != 0)
|
---|
1644 | continue;
|
---|
1645 | } else if (s->sh_type == SHT_DYNSYM ||
|
---|
1646 | s->sh_type == SHT_STRTAB ||
|
---|
1647 | s->sh_type == SHT_HASH) {
|
---|
1648 | if (k != 1)
|
---|
1649 | continue;
|
---|
1650 | } else if (s->sh_type == SHT_RELX) {
|
---|
1651 | if (k != 2)
|
---|
1652 | continue;
|
---|
1653 | } else if (s->sh_type == SHT_NOBITS) {
|
---|
1654 | if (k != 4)
|
---|
1655 | continue;
|
---|
1656 | } else {
|
---|
1657 | if (k != 3)
|
---|
1658 | continue;
|
---|
1659 | }
|
---|
1660 | sec_order[sh_order_index++] = i;
|
---|
1661 |
|
---|
1662 | /* section matches: we align it and add its size */
|
---|
1663 | tmp = addr;
|
---|
1664 | addr = (addr + s->sh_addralign - 1) &
|
---|
1665 | ~(s->sh_addralign - 1);
|
---|
1666 | file_offset += (int) ( addr - tmp );
|
---|
1667 | s->sh_offset = file_offset;
|
---|
1668 | s->sh_addr = addr;
|
---|
1669 |
|
---|
1670 | /* update program header infos */
|
---|
1671 | if (ph->p_offset == 0) {
|
---|
1672 | ph->p_offset = file_offset;
|
---|
1673 | ph->p_vaddr = addr;
|
---|
1674 | ph->p_paddr = ph->p_vaddr;
|
---|
1675 | }
|
---|
1676 | /* update dynamic relocation infos */
|
---|
1677 | if (s->sh_type == SHT_RELX) {
|
---|
1678 | #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
|
---|
1679 | if (!strcmp(strsec->data + s->sh_name, ".rel.got")) {
|
---|
1680 | dyninf->rel_addr = addr;
|
---|
1681 | dyninf->rel_size += s->sh_size; /* XXX only first rel. */
|
---|
1682 | }
|
---|
1683 | if (!strcmp(strsec->data + s->sh_name, ".rel.bss")) {
|
---|
1684 | dyninf->bss_addr = addr;
|
---|
1685 | dyninf->bss_size = s->sh_size; /* XXX only first rel. */
|
---|
1686 | }
|
---|
1687 | #else
|
---|
1688 | if (dyninf->rel_size == 0)
|
---|
1689 | dyninf->rel_addr = addr;
|
---|
1690 | dyninf->rel_size += s->sh_size;
|
---|
1691 | #endif
|
---|
1692 | }
|
---|
1693 | addr += s->sh_size;
|
---|
1694 | if (s->sh_type != SHT_NOBITS)
|
---|
1695 | file_offset += s->sh_size;
|
---|
1696 | }
|
---|
1697 | }
|
---|
1698 | if (j == 0) {
|
---|
1699 | /* Make the first PT_LOAD segment include the program
|
---|
1700 | headers itself (and the ELF header as well), it'll
|
---|
1701 | come out with same memory use but will make various
|
---|
1702 | tools like binutils strip work better. */
|
---|
1703 | ph->p_offset &= ~(ph->p_align - 1);
|
---|
1704 | ph->p_vaddr &= ~(ph->p_align - 1);
|
---|
1705 | ph->p_paddr &= ~(ph->p_align - 1);
|
---|
1706 | }
|
---|
1707 | ph->p_filesz = file_offset - ph->p_offset;
|
---|
1708 | ph->p_memsz = addr - ph->p_vaddr;
|
---|
1709 | ph++;
|
---|
1710 | if (j == 0) {
|
---|
1711 | if (s1->output_format == TCC_OUTPUT_FORMAT_ELF) {
|
---|
1712 | /* if in the middle of a page, we duplicate the page in
|
---|
1713 | memory so that one copy is RX and the other is RW */
|
---|
1714 | if ((addr & (s_align - 1)) != 0)
|
---|
1715 | addr += s_align;
|
---|
1716 | } else {
|
---|
1717 | addr = (addr + s_align - 1) & ~(s_align - 1);
|
---|
1718 | file_offset = (file_offset + s_align - 1) & ~(s_align - 1);
|
---|
1719 | }
|
---|
1720 | }
|
---|
1721 | }
|
---|
1722 | }
|
---|
1723 |
|
---|
1724 | /* all other sections come after */
|
---|
1725 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
1726 | s = s1->sections[i];
|
---|
1727 | if (phnum > 0 && (s->sh_flags & SHF_ALLOC))
|
---|
1728 | continue;
|
---|
1729 | sec_order[sh_order_index++] = i;
|
---|
1730 |
|
---|
1731 | file_offset = (file_offset + s->sh_addralign - 1) &
|
---|
1732 | ~(s->sh_addralign - 1);
|
---|
1733 | s->sh_offset = file_offset;
|
---|
1734 | if (s->sh_type != SHT_NOBITS)
|
---|
1735 | file_offset += s->sh_size;
|
---|
1736 | }
|
---|
1737 |
|
---|
1738 | return file_offset;
|
---|
1739 | }
|
---|
1740 |
|
---|
1741 | static void fill_unloadable_phdr(ElfW(Phdr) *phdr, int phnum, Section *interp,
|
---|
1742 | Section *dynamic)
|
---|
1743 | {
|
---|
1744 | ElfW(Phdr) *ph;
|
---|
1745 |
|
---|
1746 | /* if interpreter, then add corresponding program header */
|
---|
1747 | if (interp) {
|
---|
1748 | ph = &phdr[0];
|
---|
1749 |
|
---|
1750 | ph->p_type = PT_PHDR;
|
---|
1751 | ph->p_offset = sizeof(ElfW(Ehdr));
|
---|
1752 | ph->p_filesz = ph->p_memsz = phnum * sizeof(ElfW(Phdr));
|
---|
1753 | ph->p_vaddr = interp->sh_addr - ph->p_filesz;
|
---|
1754 | ph->p_paddr = ph->p_vaddr;
|
---|
1755 | ph->p_flags = PF_R | PF_X;
|
---|
1756 | ph->p_align = 4; /* interp->sh_addralign; */
|
---|
1757 | ph++;
|
---|
1758 |
|
---|
1759 | ph->p_type = PT_INTERP;
|
---|
1760 | ph->p_offset = interp->sh_offset;
|
---|
1761 | ph->p_vaddr = interp->sh_addr;
|
---|
1762 | ph->p_paddr = ph->p_vaddr;
|
---|
1763 | ph->p_filesz = interp->sh_size;
|
---|
1764 | ph->p_memsz = interp->sh_size;
|
---|
1765 | ph->p_flags = PF_R;
|
---|
1766 | ph->p_align = interp->sh_addralign;
|
---|
1767 | }
|
---|
1768 |
|
---|
1769 | /* if dynamic section, then add corresponding program header */
|
---|
1770 | if (dynamic) {
|
---|
1771 | ph = &phdr[phnum - 1];
|
---|
1772 |
|
---|
1773 | ph->p_type = PT_DYNAMIC;
|
---|
1774 | ph->p_offset = dynamic->sh_offset;
|
---|
1775 | ph->p_vaddr = dynamic->sh_addr;
|
---|
1776 | ph->p_paddr = ph->p_vaddr;
|
---|
1777 | ph->p_filesz = dynamic->sh_size;
|
---|
1778 | ph->p_memsz = dynamic->sh_size;
|
---|
1779 | ph->p_flags = PF_R | PF_W;
|
---|
1780 | ph->p_align = dynamic->sh_addralign;
|
---|
1781 | }
|
---|
1782 | }
|
---|
1783 |
|
---|
1784 | /* Fill the dynamic section with tags describing the address and size of
|
---|
1785 | sections */
|
---|
1786 | static void fill_dynamic(TCCState *s1, struct dyn_inf *dyninf)
|
---|
1787 | {
|
---|
1788 | Section *dynamic = dyninf->dynamic;
|
---|
1789 |
|
---|
1790 | /* put dynamic section entries */
|
---|
1791 | put_dt(dynamic, DT_HASH, s1->dynsym->hash->sh_addr);
|
---|
1792 | put_dt(dynamic, DT_STRTAB, dyninf->dynstr->sh_addr);
|
---|
1793 | put_dt(dynamic, DT_SYMTAB, s1->dynsym->sh_addr);
|
---|
1794 | put_dt(dynamic, DT_STRSZ, dyninf->dynstr->data_offset);
|
---|
1795 | put_dt(dynamic, DT_SYMENT, sizeof(ElfW(Sym)));
|
---|
1796 | #if PTR_SIZE == 8
|
---|
1797 | put_dt(dynamic, DT_RELA, dyninf->rel_addr);
|
---|
1798 | put_dt(dynamic, DT_RELASZ, dyninf->rel_size);
|
---|
1799 | put_dt(dynamic, DT_RELAENT, sizeof(ElfW_Rel));
|
---|
1800 | #else
|
---|
1801 | #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
|
---|
1802 | put_dt(dynamic, DT_PLTGOT, s1->got->sh_addr);
|
---|
1803 | put_dt(dynamic, DT_PLTRELSZ, dyninf->rel_size);
|
---|
1804 | put_dt(dynamic, DT_JMPREL, dyninf->rel_addr);
|
---|
1805 | put_dt(dynamic, DT_PLTREL, DT_REL);
|
---|
1806 | put_dt(dynamic, DT_REL, dyninf->bss_addr);
|
---|
1807 | put_dt(dynamic, DT_RELSZ, dyninf->bss_size);
|
---|
1808 | #else
|
---|
1809 | put_dt(dynamic, DT_REL, dyninf->rel_addr);
|
---|
1810 | put_dt(dynamic, DT_RELSZ, dyninf->rel_size);
|
---|
1811 | put_dt(dynamic, DT_RELENT, sizeof(ElfW_Rel));
|
---|
1812 | #endif
|
---|
1813 | #endif
|
---|
1814 | if (s1->do_debug)
|
---|
1815 | put_dt(dynamic, DT_DEBUG, 0);
|
---|
1816 | put_dt(dynamic, DT_NULL, 0);
|
---|
1817 | }
|
---|
1818 |
|
---|
1819 | /* Relocate remaining sections and symbols (that is those not related to
|
---|
1820 | dynamic linking) */
|
---|
1821 | static int final_sections_reloc(TCCState *s1)
|
---|
1822 | {
|
---|
1823 | int i;
|
---|
1824 | Section *s;
|
---|
1825 |
|
---|
1826 | relocate_syms(s1, s1->symtab, 0);
|
---|
1827 |
|
---|
1828 | if (s1->nb_errors != 0)
|
---|
1829 | return -1;
|
---|
1830 |
|
---|
1831 | /* relocate sections */
|
---|
1832 | /* XXX: ignore sections with allocated relocations ? */
|
---|
1833 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
1834 | s = s1->sections[i];
|
---|
1835 | #if defined(TCC_TARGET_I386) || defined(TCC_MUSL)
|
---|
1836 | if (s->reloc && s != s1->got && (s->sh_flags & SHF_ALLOC)) //gr
|
---|
1837 | /* On X86 gdb 7.3 works in any case but gdb 6.6 will crash if SHF_ALLOC
|
---|
1838 | checking is removed */
|
---|
1839 | #else
|
---|
1840 | if (s->reloc && s != s1->got)
|
---|
1841 | /* On X86_64 gdb 7.3 will crash if SHF_ALLOC checking is present */
|
---|
1842 | #endif
|
---|
1843 | relocate_section(s1, s);
|
---|
1844 | }
|
---|
1845 |
|
---|
1846 | /* relocate relocation entries if the relocation tables are
|
---|
1847 | allocated in the executable */
|
---|
1848 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
1849 | s = s1->sections[i];
|
---|
1850 | if ((s->sh_flags & SHF_ALLOC) &&
|
---|
1851 | s->sh_type == SHT_RELX) {
|
---|
1852 | relocate_rel(s1, s);
|
---|
1853 | }
|
---|
1854 | }
|
---|
1855 | return 0;
|
---|
1856 | }
|
---|
1857 |
|
---|
1858 | /* Create an ELF file on disk.
|
---|
1859 | This function handle ELF specific layout requirements */
|
---|
1860 | static void tcc_output_elf(TCCState *s1, FILE *f, int phnum, ElfW(Phdr) *phdr,
|
---|
1861 | int file_offset, int *sec_order)
|
---|
1862 | {
|
---|
1863 | int i, shnum, offset, size, file_type;
|
---|
1864 | Section *s;
|
---|
1865 | ElfW(Ehdr) ehdr;
|
---|
1866 | ElfW(Shdr) shdr, *sh;
|
---|
1867 |
|
---|
1868 | file_type = s1->output_type;
|
---|
1869 | shnum = s1->nb_sections;
|
---|
1870 |
|
---|
1871 | memset(&ehdr, 0, sizeof(ehdr));
|
---|
1872 |
|
---|
1873 | if (phnum > 0) {
|
---|
1874 | ehdr.e_phentsize = sizeof(ElfW(Phdr));
|
---|
1875 | ehdr.e_phnum = phnum;
|
---|
1876 | ehdr.e_phoff = sizeof(ElfW(Ehdr));
|
---|
1877 | }
|
---|
1878 |
|
---|
1879 | /* align to 4 */
|
---|
1880 | file_offset = (file_offset + 3) & -4;
|
---|
1881 |
|
---|
1882 | /* fill header */
|
---|
1883 | ehdr.e_ident[0] = ELFMAG0;
|
---|
1884 | ehdr.e_ident[1] = ELFMAG1;
|
---|
1885 | ehdr.e_ident[2] = ELFMAG2;
|
---|
1886 | ehdr.e_ident[3] = ELFMAG3;
|
---|
1887 | ehdr.e_ident[4] = ELFCLASSW;
|
---|
1888 | ehdr.e_ident[5] = ELFDATA2LSB;
|
---|
1889 | ehdr.e_ident[6] = EV_CURRENT;
|
---|
1890 | #if !defined(TCC_TARGET_PE) && (defined(__FreeBSD__) || defined(__FreeBSD_kernel__))
|
---|
1891 | /* FIXME: should set only for freebsd _target_, but we exclude only PE target */
|
---|
1892 | ehdr.e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
|
---|
1893 | #endif
|
---|
1894 | #ifdef TCC_TARGET_ARM
|
---|
1895 | #ifdef TCC_ARM_EABI
|
---|
1896 | ehdr.e_ident[EI_OSABI] = 0;
|
---|
1897 | ehdr.e_flags = EF_ARM_EABI_VER4;
|
---|
1898 | if (file_type == TCC_OUTPUT_EXE || file_type == TCC_OUTPUT_DLL)
|
---|
1899 | ehdr.e_flags |= EF_ARM_HASENTRY;
|
---|
1900 | if (s1->float_abi == ARM_HARD_FLOAT)
|
---|
1901 | ehdr.e_flags |= EF_ARM_VFP_FLOAT;
|
---|
1902 | else
|
---|
1903 | ehdr.e_flags |= EF_ARM_SOFT_FLOAT;
|
---|
1904 | #else
|
---|
1905 | ehdr.e_ident[EI_OSABI] = ELFOSABI_ARM;
|
---|
1906 | #endif
|
---|
1907 | #endif
|
---|
1908 | switch(file_type) {
|
---|
1909 | default:
|
---|
1910 | case TCC_OUTPUT_EXE:
|
---|
1911 | ehdr.e_type = ET_EXEC;
|
---|
1912 | ehdr.e_entry = get_elf_sym_addr(s1, "_start", 1);
|
---|
1913 | break;
|
---|
1914 | case TCC_OUTPUT_DLL:
|
---|
1915 | ehdr.e_type = ET_DYN;
|
---|
1916 | ehdr.e_entry = text_section->sh_addr; /* XXX: is it correct ? */
|
---|
1917 | break;
|
---|
1918 | case TCC_OUTPUT_OBJ:
|
---|
1919 | ehdr.e_type = ET_REL;
|
---|
1920 | break;
|
---|
1921 | }
|
---|
1922 | ehdr.e_machine = EM_TCC_TARGET;
|
---|
1923 | ehdr.e_version = EV_CURRENT;
|
---|
1924 | ehdr.e_shoff = file_offset;
|
---|
1925 | ehdr.e_ehsize = sizeof(ElfW(Ehdr));
|
---|
1926 | ehdr.e_shentsize = sizeof(ElfW(Shdr));
|
---|
1927 | ehdr.e_shnum = shnum;
|
---|
1928 | ehdr.e_shstrndx = shnum - 1;
|
---|
1929 |
|
---|
1930 | fwrite(&ehdr, 1, sizeof(ElfW(Ehdr)), f);
|
---|
1931 | fwrite(phdr, 1, phnum * sizeof(ElfW(Phdr)), f);
|
---|
1932 | offset = sizeof(ElfW(Ehdr)) + phnum * sizeof(ElfW(Phdr));
|
---|
1933 |
|
---|
1934 | sort_syms(s1, symtab_section);
|
---|
1935 | for(i = 1; i < s1->nb_sections; i++) {
|
---|
1936 | s = s1->sections[sec_order[i]];
|
---|
1937 | if (s->sh_type != SHT_NOBITS) {
|
---|
1938 | while (offset < s->sh_offset) {
|
---|
1939 | fputc(0, f);
|
---|
1940 | offset++;
|
---|
1941 | }
|
---|
1942 | size = s->sh_size;
|
---|
1943 | if (size)
|
---|
1944 | fwrite(s->data, 1, size, f);
|
---|
1945 | offset += size;
|
---|
1946 | }
|
---|
1947 | }
|
---|
1948 |
|
---|
1949 | /* output section headers */
|
---|
1950 | while (offset < ehdr.e_shoff) {
|
---|
1951 | fputc(0, f);
|
---|
1952 | offset++;
|
---|
1953 | }
|
---|
1954 |
|
---|
1955 | for(i = 0; i < s1->nb_sections; i++) {
|
---|
1956 | sh = &shdr;
|
---|
1957 | memset(sh, 0, sizeof(ElfW(Shdr)));
|
---|
1958 | s = s1->sections[i];
|
---|
1959 | if (s) {
|
---|
1960 | sh->sh_name = s->sh_name;
|
---|
1961 | sh->sh_type = s->sh_type;
|
---|
1962 | sh->sh_flags = s->sh_flags;
|
---|
1963 | sh->sh_entsize = s->sh_entsize;
|
---|
1964 | sh->sh_info = s->sh_info;
|
---|
1965 | if (s->link)
|
---|
1966 | sh->sh_link = s->link->sh_num;
|
---|
1967 | sh->sh_addralign = s->sh_addralign;
|
---|
1968 | sh->sh_addr = s->sh_addr;
|
---|
1969 | sh->sh_offset = s->sh_offset;
|
---|
1970 | sh->sh_size = s->sh_size;
|
---|
1971 | }
|
---|
1972 | fwrite(sh, 1, sizeof(ElfW(Shdr)), f);
|
---|
1973 | }
|
---|
1974 | }
|
---|
1975 |
|
---|
1976 | /* Write an elf, coff or "binary" file */
|
---|
1977 | static int tcc_write_elf_file(TCCState *s1, const char *filename, int phnum,
|
---|
1978 | ElfW(Phdr) *phdr, int file_offset, int *sec_order)
|
---|
1979 | {
|
---|
1980 | int fd, mode, file_type;
|
---|
1981 | FILE *f;
|
---|
1982 |
|
---|
1983 | file_type = s1->output_type;
|
---|
1984 | if (file_type == TCC_OUTPUT_OBJ)
|
---|
1985 | mode = 0666;
|
---|
1986 | else
|
---|
1987 | mode = 0777;
|
---|
1988 | unlink(filename);
|
---|
1989 | fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, mode);
|
---|
1990 | if (fd < 0) {
|
---|
1991 | tcc_error_noabort("could not write '%s'", filename);
|
---|
1992 | return -1;
|
---|
1993 | }
|
---|
1994 | f = fdopen(fd, "wb");
|
---|
1995 | if (s1->verbose)
|
---|
1996 | printf("<- %s\n", filename);
|
---|
1997 |
|
---|
1998 | #ifdef TCC_TARGET_COFF
|
---|
1999 | if (s1->output_format == TCC_OUTPUT_FORMAT_COFF)
|
---|
2000 | tcc_output_coff(s1, f);
|
---|
2001 | else
|
---|
2002 | #endif
|
---|
2003 | if (s1->output_format == TCC_OUTPUT_FORMAT_ELF)
|
---|
2004 | tcc_output_elf(s1, f, phnum, phdr, file_offset, sec_order);
|
---|
2005 | else
|
---|
2006 | tcc_output_binary(s1, f, sec_order);
|
---|
2007 | fclose(f);
|
---|
2008 |
|
---|
2009 | return 0;
|
---|
2010 | }
|
---|
2011 |
|
---|
2012 | /* Sort section headers by assigned sh_addr, remove sections
|
---|
2013 | that we aren't going to output. */
|
---|
2014 | static void tidy_section_headers(TCCState *s1, int *sec_order)
|
---|
2015 | {
|
---|
2016 | int i, nnew, l, *backmap;
|
---|
2017 | Section **snew, *s;
|
---|
2018 | ElfW(Sym) *sym;
|
---|
2019 |
|
---|
2020 | snew = tcc_malloc(s1->nb_sections * sizeof(snew[0]));
|
---|
2021 | backmap = tcc_malloc(s1->nb_sections * sizeof(backmap[0]));
|
---|
2022 | for (i = 0, nnew = 0, l = s1->nb_sections; i < s1->nb_sections; i++) {
|
---|
2023 | s = s1->sections[sec_order[i]];
|
---|
2024 | if (!i || s->sh_name) {
|
---|
2025 | backmap[sec_order[i]] = nnew;
|
---|
2026 | snew[nnew] = s;
|
---|
2027 | ++nnew;
|
---|
2028 | } else {
|
---|
2029 | backmap[sec_order[i]] = 0;
|
---|
2030 | snew[--l] = s;
|
---|
2031 | }
|
---|
2032 | }
|
---|
2033 | for (i = 0; i < nnew; i++) {
|
---|
2034 | s = snew[i];
|
---|
2035 | if (s) {
|
---|
2036 | s->sh_num = i;
|
---|
2037 | if (s->sh_type == SHT_RELX)
|
---|
2038 | s->sh_info = backmap[s->sh_info];
|
---|
2039 | }
|
---|
2040 | }
|
---|
2041 |
|
---|
2042 | for_each_elem(symtab_section, 1, sym, ElfW(Sym))
|
---|
2043 | if (sym->st_shndx != SHN_UNDEF && sym->st_shndx < SHN_LORESERVE)
|
---|
2044 | sym->st_shndx = backmap[sym->st_shndx];
|
---|
2045 | if( !s1->static_link ) {
|
---|
2046 | for_each_elem(s1->dynsym, 1, sym, ElfW(Sym))
|
---|
2047 | if (sym->st_shndx != SHN_UNDEF && sym->st_shndx < SHN_LORESERVE)
|
---|
2048 | sym->st_shndx = backmap[sym->st_shndx];
|
---|
2049 | }
|
---|
2050 | for (i = 0; i < s1->nb_sections; i++)
|
---|
2051 | sec_order[i] = i;
|
---|
2052 | tcc_free(s1->sections);
|
---|
2053 | s1->sections = snew;
|
---|
2054 | s1->nb_sections = nnew;
|
---|
2055 | tcc_free(backmap);
|
---|
2056 | }
|
---|
2057 |
|
---|
2058 | /* Output an elf, coff or binary file */
|
---|
2059 | /* XXX: suppress unneeded sections */
|
---|
2060 | static int elf_output_file(TCCState *s1, const char *filename)
|
---|
2061 | {
|
---|
2062 | int i, ret, phnum, shnum, file_type, file_offset, *sec_order;
|
---|
2063 | struct dyn_inf dyninf = {0};
|
---|
2064 | ElfW(Phdr) *phdr;
|
---|
2065 | ElfW(Sym) *sym;
|
---|
2066 | Section *strsec, *interp, *dynamic, *dynstr;
|
---|
2067 | int textrel;
|
---|
2068 |
|
---|
2069 | file_type = s1->output_type;
|
---|
2070 | s1->nb_errors = 0;
|
---|
2071 | ret = -1;
|
---|
2072 | phdr = NULL;
|
---|
2073 | sec_order = NULL;
|
---|
2074 | interp = dynamic = dynstr = NULL; /* avoid warning */
|
---|
2075 | textrel = 0;
|
---|
2076 |
|
---|
2077 | if (file_type != TCC_OUTPUT_OBJ) {
|
---|
2078 | /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
|
---|
2079 | tcc_add_runtime(s1);
|
---|
2080 | resolve_common_syms(s1);
|
---|
2081 |
|
---|
2082 | if (!s1->static_link) {
|
---|
2083 | if (file_type == TCC_OUTPUT_EXE) {
|
---|
2084 | char *ptr;
|
---|
2085 | /* allow override the dynamic loader */
|
---|
2086 | const char *elfint = getenv("LD_SO");
|
---|
2087 | if (elfint == NULL)
|
---|
2088 | elfint = DEFAULT_ELFINTERP(s1);
|
---|
2089 | /* add interpreter section only if executable */
|
---|
2090 | interp = new_section(s1, ".interp", SHT_PROGBITS, SHF_ALLOC);
|
---|
2091 | interp->sh_addralign = 1;
|
---|
2092 | ptr = section_ptr_add(interp, 1 + strlen(elfint));
|
---|
2093 | strcpy(ptr, elfint);
|
---|
2094 | }
|
---|
2095 |
|
---|
2096 | /* add dynamic symbol table */
|
---|
2097 | s1->dynsym = new_symtab(s1, ".dynsym", SHT_DYNSYM, SHF_ALLOC,
|
---|
2098 | ".dynstr",
|
---|
2099 | ".hash", SHF_ALLOC);
|
---|
2100 | dynstr = s1->dynsym->link;
|
---|
2101 |
|
---|
2102 | /* add dynamic section */
|
---|
2103 | dynamic = new_section(s1, ".dynamic", SHT_DYNAMIC,
|
---|
2104 | SHF_ALLOC | SHF_WRITE);
|
---|
2105 | dynamic->link = dynstr;
|
---|
2106 | dynamic->sh_entsize = sizeof(ElfW(Dyn));
|
---|
2107 |
|
---|
2108 | build_got(s1);
|
---|
2109 |
|
---|
2110 | if (file_type == TCC_OUTPUT_EXE) {
|
---|
2111 | bind_exe_dynsyms(s1);
|
---|
2112 | if (s1->nb_errors)
|
---|
2113 | goto the_end;
|
---|
2114 | bind_libs_dynsyms(s1);
|
---|
2115 | } else {
|
---|
2116 | /* shared library case: simply export all global symbols */
|
---|
2117 | export_global_syms(s1);
|
---|
2118 | }
|
---|
2119 | }
|
---|
2120 | build_got_entries(s1);
|
---|
2121 | }
|
---|
2122 |
|
---|
2123 | /* we add a section for symbols */
|
---|
2124 | strsec = new_section(s1, ".shstrtab", SHT_STRTAB, 0);
|
---|
2125 | put_elf_str(strsec, "");
|
---|
2126 |
|
---|
2127 | /* Allocate strings for section names */
|
---|
2128 | textrel = alloc_sec_names(s1, file_type, strsec);
|
---|
2129 |
|
---|
2130 | if (dynamic) {
|
---|
2131 | /* add a list of needed dlls */
|
---|
2132 | for(i = 0; i < s1->nb_loaded_dlls; i++) {
|
---|
2133 | DLLReference *dllref = s1->loaded_dlls[i];
|
---|
2134 | if (dllref->level == 0)
|
---|
2135 | put_dt(dynamic, DT_NEEDED, put_elf_str(dynstr, dllref->name));
|
---|
2136 | }
|
---|
2137 |
|
---|
2138 | if (s1->rpath)
|
---|
2139 | put_dt(dynamic, s1->enable_new_dtags ? DT_RUNPATH : DT_RPATH,
|
---|
2140 | put_elf_str(dynstr, s1->rpath));
|
---|
2141 |
|
---|
2142 | if (file_type == TCC_OUTPUT_DLL) {
|
---|
2143 | if (s1->soname)
|
---|
2144 | put_dt(dynamic, DT_SONAME, put_elf_str(dynstr, s1->soname));
|
---|
2145 | /* XXX: currently, since we do not handle PIC code, we
|
---|
2146 | must relocate the readonly segments */
|
---|
2147 | if (textrel)
|
---|
2148 | put_dt(dynamic, DT_TEXTREL, 0);
|
---|
2149 | }
|
---|
2150 |
|
---|
2151 | if (s1->symbolic)
|
---|
2152 | put_dt(dynamic, DT_SYMBOLIC, 0);
|
---|
2153 |
|
---|
2154 | dyninf.dynamic = dynamic;
|
---|
2155 | dyninf.dynstr = dynstr;
|
---|
2156 | /* remember offset and reserve space for 2nd call below */
|
---|
2157 | dyninf.data_offset = dynamic->data_offset;
|
---|
2158 | fill_dynamic(s1, &dyninf);
|
---|
2159 | dynamic->sh_size = dynamic->data_offset;
|
---|
2160 | dynstr->sh_size = dynstr->data_offset;
|
---|
2161 | }
|
---|
2162 |
|
---|
2163 | /* compute number of program headers */
|
---|
2164 | if (file_type == TCC_OUTPUT_OBJ)
|
---|
2165 | phnum = 0;
|
---|
2166 | else if (file_type == TCC_OUTPUT_DLL)
|
---|
2167 | phnum = 3;
|
---|
2168 | else if (s1->static_link)
|
---|
2169 | phnum = 2;
|
---|
2170 | else
|
---|
2171 | phnum = 5;
|
---|
2172 |
|
---|
2173 | /* allocate program segment headers */
|
---|
2174 | phdr = tcc_mallocz(phnum * sizeof(ElfW(Phdr)));
|
---|
2175 |
|
---|
2176 | /* compute number of sections */
|
---|
2177 | shnum = s1->nb_sections;
|
---|
2178 |
|
---|
2179 | /* this array is used to reorder sections in the output file */
|
---|
2180 | sec_order = tcc_malloc(sizeof(int) * shnum);
|
---|
2181 | sec_order[0] = 0;
|
---|
2182 |
|
---|
2183 | /* compute section to program header mapping */
|
---|
2184 | file_offset = layout_sections(s1, phdr, phnum, interp, strsec, &dyninf,
|
---|
2185 | sec_order);
|
---|
2186 |
|
---|
2187 | /* Fill remaining program header and finalize relocation related to dynamic
|
---|
2188 | linking. */
|
---|
2189 | if (file_type != TCC_OUTPUT_OBJ) {
|
---|
2190 | fill_unloadable_phdr(phdr, phnum, interp, dynamic);
|
---|
2191 | if (dynamic) {
|
---|
2192 | dynamic->data_offset = dyninf.data_offset;
|
---|
2193 | fill_dynamic(s1, &dyninf);
|
---|
2194 |
|
---|
2195 | /* put in GOT the dynamic section address and relocate PLT */
|
---|
2196 | write32le(s1->got->data, dynamic->sh_addr);
|
---|
2197 | if (file_type == TCC_OUTPUT_EXE
|
---|
2198 | || (RELOCATE_DLLPLT && file_type == TCC_OUTPUT_DLL))
|
---|
2199 | relocate_plt(s1);
|
---|
2200 |
|
---|
2201 | /* relocate symbols in .dynsym now that final addresses are known */
|
---|
2202 | for_each_elem(s1->dynsym, 1, sym, ElfW(Sym)) {
|
---|
2203 | if (sym->st_shndx != SHN_UNDEF && sym->st_shndx < SHN_LORESERVE) {
|
---|
2204 | /* do symbol relocation */
|
---|
2205 | sym->st_value += s1->sections[sym->st_shndx]->sh_addr;
|
---|
2206 | }
|
---|
2207 | }
|
---|
2208 | }
|
---|
2209 |
|
---|
2210 | /* if building executable or DLL, then relocate each section
|
---|
2211 | except the GOT which is already relocated */
|
---|
2212 | ret = final_sections_reloc(s1);
|
---|
2213 | if (ret)
|
---|
2214 | goto the_end;
|
---|
2215 | tidy_section_headers(s1, sec_order);
|
---|
2216 |
|
---|
2217 | /* Perform relocation to GOT or PLT entries */
|
---|
2218 | if (file_type == TCC_OUTPUT_EXE && s1->static_link)
|
---|
2219 | fill_got(s1);
|
---|
2220 | else if (s1->got)
|
---|
2221 | fill_local_got_entries(s1);
|
---|
2222 | }
|
---|
2223 |
|
---|
2224 | /* Create the ELF file with name 'filename' */
|
---|
2225 | ret = tcc_write_elf_file(s1, filename, phnum, phdr, file_offset, sec_order);
|
---|
2226 | s1->nb_sections = shnum;
|
---|
2227 | the_end:
|
---|
2228 | tcc_free(sec_order);
|
---|
2229 | tcc_free(phdr);
|
---|
2230 | return ret;
|
---|
2231 | }
|
---|
2232 |
|
---|
2233 | LIBTCCAPI int tcc_output_file(TCCState *s, const char *filename)
|
---|
2234 | {
|
---|
2235 | int ret;
|
---|
2236 | #ifdef TCC_TARGET_PE
|
---|
2237 | if (s->output_type != TCC_OUTPUT_OBJ) {
|
---|
2238 | ret = pe_output_file(s, filename);
|
---|
2239 | } else
|
---|
2240 | #endif
|
---|
2241 | ret = elf_output_file(s, filename);
|
---|
2242 | return ret;
|
---|
2243 | }
|
---|
2244 |
|
---|
2245 | static void *load_data(int fd, unsigned long file_offset, unsigned long size)
|
---|
2246 | {
|
---|
2247 | void *data;
|
---|
2248 |
|
---|
2249 | data = tcc_malloc(size);
|
---|
2250 | lseek(fd, file_offset, SEEK_SET);
|
---|
2251 | read(fd, data, size);
|
---|
2252 | return data;
|
---|
2253 | }
|
---|
2254 |
|
---|
2255 | typedef struct SectionMergeInfo {
|
---|
2256 | Section *s; /* corresponding existing section */
|
---|
2257 | unsigned long offset; /* offset of the new section in the existing section */
|
---|
2258 | uint8_t new_section; /* true if section 's' was added */
|
---|
2259 | uint8_t link_once; /* true if link once section */
|
---|
2260 | } SectionMergeInfo;
|
---|
2261 |
|
---|
2262 | ST_FUNC int tcc_object_type(int fd, ElfW(Ehdr) *h)
|
---|
2263 | {
|
---|
2264 | int size = read(fd, h, sizeof *h);
|
---|
2265 | if (size == sizeof *h && 0 == memcmp(h, ELFMAG, 4)) {
|
---|
2266 | if (h->e_type == ET_REL)
|
---|
2267 | return AFF_BINTYPE_REL;
|
---|
2268 | if (h->e_type == ET_DYN)
|
---|
2269 | return AFF_BINTYPE_DYN;
|
---|
2270 | } else if (size >= 8) {
|
---|
2271 | if (0 == memcmp(h, ARMAG, 8))
|
---|
2272 | return AFF_BINTYPE_AR;
|
---|
2273 | #ifdef TCC_TARGET_COFF
|
---|
2274 | if (((struct filehdr*)h)->f_magic == COFF_C67_MAGIC)
|
---|
2275 | return AFF_BINTYPE_C67;
|
---|
2276 | #endif
|
---|
2277 | }
|
---|
2278 | return 0;
|
---|
2279 | }
|
---|
2280 |
|
---|
2281 | /* load an object file and merge it with current files */
|
---|
2282 | /* XXX: handle correctly stab (debug) info */
|
---|
2283 | ST_FUNC int tcc_load_object_file(TCCState *s1,
|
---|
2284 | int fd, unsigned long file_offset)
|
---|
2285 | {
|
---|
2286 | ElfW(Ehdr) ehdr;
|
---|
2287 | ElfW(Shdr) *shdr, *sh;
|
---|
2288 | int size, i, j, offset, offseti, nb_syms, sym_index, ret, seencompressed;
|
---|
2289 | unsigned char *strsec, *strtab;
|
---|
2290 | int *old_to_new_syms;
|
---|
2291 | char *sh_name, *name;
|
---|
2292 | SectionMergeInfo *sm_table, *sm;
|
---|
2293 | ElfW(Sym) *sym, *symtab;
|
---|
2294 | ElfW_Rel *rel;
|
---|
2295 | Section *s;
|
---|
2296 |
|
---|
2297 | int stab_index;
|
---|
2298 | int stabstr_index;
|
---|
2299 |
|
---|
2300 | stab_index = stabstr_index = 0;
|
---|
2301 |
|
---|
2302 | lseek(fd, file_offset, SEEK_SET);
|
---|
2303 | if (tcc_object_type(fd, &ehdr) != AFF_BINTYPE_REL)
|
---|
2304 | goto fail1;
|
---|
2305 | /* test CPU specific stuff */
|
---|
2306 | if (ehdr.e_ident[5] != ELFDATA2LSB ||
|
---|
2307 | ehdr.e_machine != EM_TCC_TARGET) {
|
---|
2308 | fail1:
|
---|
2309 | tcc_error_noabort("invalid object file");
|
---|
2310 | return -1;
|
---|
2311 | }
|
---|
2312 | /* read sections */
|
---|
2313 | shdr = load_data(fd, file_offset + ehdr.e_shoff,
|
---|
2314 | sizeof(ElfW(Shdr)) * ehdr.e_shnum);
|
---|
2315 | sm_table = tcc_mallocz(sizeof(SectionMergeInfo) * ehdr.e_shnum);
|
---|
2316 |
|
---|
2317 | /* load section names */
|
---|
2318 | sh = &shdr[ehdr.e_shstrndx];
|
---|
2319 | strsec = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
|
---|
2320 |
|
---|
2321 | /* load symtab and strtab */
|
---|
2322 | old_to_new_syms = NULL;
|
---|
2323 | symtab = NULL;
|
---|
2324 | strtab = NULL;
|
---|
2325 | nb_syms = 0;
|
---|
2326 | seencompressed = 0;
|
---|
2327 | for(i = 1; i < ehdr.e_shnum; i++) {
|
---|
2328 | sh = &shdr[i];
|
---|
2329 | if (sh->sh_type == SHT_SYMTAB) {
|
---|
2330 | if (symtab) {
|
---|
2331 | tcc_error_noabort("object must contain only one symtab");
|
---|
2332 | fail:
|
---|
2333 | ret = -1;
|
---|
2334 | goto the_end;
|
---|
2335 | }
|
---|
2336 | nb_syms = sh->sh_size / sizeof(ElfW(Sym));
|
---|
2337 | symtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
|
---|
2338 | sm_table[i].s = symtab_section;
|
---|
2339 |
|
---|
2340 | /* now load strtab */
|
---|
2341 | sh = &shdr[sh->sh_link];
|
---|
2342 | strtab = load_data(fd, file_offset + sh->sh_offset, sh->sh_size);
|
---|
2343 | }
|
---|
2344 | if (sh->sh_flags & SHF_COMPRESSED)
|
---|
2345 | seencompressed = 1;
|
---|
2346 | }
|
---|
2347 |
|
---|
2348 | /* now examine each section and try to merge its content with the
|
---|
2349 | ones in memory */
|
---|
2350 | for(i = 1; i < ehdr.e_shnum; i++) {
|
---|
2351 | /* no need to examine section name strtab */
|
---|
2352 | if (i == ehdr.e_shstrndx)
|
---|
2353 | continue;
|
---|
2354 | sh = &shdr[i];
|
---|
2355 | sh_name = (char *) strsec + sh->sh_name;
|
---|
2356 | /* ignore sections types we do not handle */
|
---|
2357 | if (sh->sh_type != SHT_PROGBITS &&
|
---|
2358 | sh->sh_type != SHT_RELX &&
|
---|
2359 | #ifdef TCC_ARM_EABI
|
---|
2360 | sh->sh_type != SHT_ARM_EXIDX &&
|
---|
2361 | #endif
|
---|
2362 | sh->sh_type != SHT_NOBITS &&
|
---|
2363 | sh->sh_type != SHT_PREINIT_ARRAY &&
|
---|
2364 | sh->sh_type != SHT_INIT_ARRAY &&
|
---|
2365 | sh->sh_type != SHT_FINI_ARRAY &&
|
---|
2366 | strcmp(sh_name, ".stabstr")
|
---|
2367 | )
|
---|
2368 | continue;
|
---|
2369 | if (seencompressed
|
---|
2370 | && (!strncmp(sh_name, ".debug_", sizeof(".debug_")-1)
|
---|
2371 | || (sh->sh_type == SHT_RELX
|
---|
2372 | && !strncmp((char*)strsec + shdr[sh->sh_info].sh_name,
|
---|
2373 | ".debug_", sizeof(".debug_")-1))))
|
---|
2374 | continue;
|
---|
2375 | if (sh->sh_addralign < 1)
|
---|
2376 | sh->sh_addralign = 1;
|
---|
2377 | /* find corresponding section, if any */
|
---|
2378 | for(j = 1; j < s1->nb_sections;j++) {
|
---|
2379 | s = s1->sections[j];
|
---|
2380 | if (!strcmp(s->name, sh_name)) {
|
---|
2381 | if (!strncmp(sh_name, ".gnu.linkonce",
|
---|
2382 | sizeof(".gnu.linkonce") - 1)) {
|
---|
2383 | /* if a 'linkonce' section is already present, we
|
---|
2384 | do not add it again. It is a little tricky as
|
---|
2385 | symbols can still be defined in
|
---|
2386 | it. */
|
---|
2387 | sm_table[i].link_once = 1;
|
---|
2388 | goto next;
|
---|
2389 | } else {
|
---|
2390 | goto found;
|
---|
2391 | }
|
---|
2392 | }
|
---|
2393 | }
|
---|
2394 | /* not found: create new section */
|
---|
2395 | s = new_section(s1, sh_name, sh->sh_type, sh->sh_flags & ~SHF_GROUP);
|
---|
2396 | /* take as much info as possible from the section. sh_link and
|
---|
2397 | sh_info will be updated later */
|
---|
2398 | s->sh_addralign = sh->sh_addralign;
|
---|
2399 | s->sh_entsize = sh->sh_entsize;
|
---|
2400 | sm_table[i].new_section = 1;
|
---|
2401 | found:
|
---|
2402 | if (sh->sh_type != s->sh_type) {
|
---|
2403 | tcc_error_noabort("invalid section type");
|
---|
2404 | goto fail;
|
---|
2405 | }
|
---|
2406 |
|
---|
2407 | /* align start of section */
|
---|
2408 | offset = s->data_offset;
|
---|
2409 |
|
---|
2410 | if (0 == strcmp(sh_name, ".stab")) {
|
---|
2411 | stab_index = i;
|
---|
2412 | goto no_align;
|
---|
2413 | }
|
---|
2414 | if (0 == strcmp(sh_name, ".stabstr")) {
|
---|
2415 | stabstr_index = i;
|
---|
2416 | goto no_align;
|
---|
2417 | }
|
---|
2418 |
|
---|
2419 | size = sh->sh_addralign - 1;
|
---|
2420 | offset = (offset + size) & ~size;
|
---|
2421 | if (sh->sh_addralign > s->sh_addralign)
|
---|
2422 | s->sh_addralign = sh->sh_addralign;
|
---|
2423 | s->data_offset = offset;
|
---|
2424 | no_align:
|
---|
2425 | sm_table[i].offset = offset;
|
---|
2426 | sm_table[i].s = s;
|
---|
2427 | /* concatenate sections */
|
---|
2428 | size = sh->sh_size;
|
---|
2429 | if (sh->sh_type != SHT_NOBITS) {
|
---|
2430 | unsigned char *ptr;
|
---|
2431 | lseek(fd, file_offset + sh->sh_offset, SEEK_SET);
|
---|
2432 | ptr = section_ptr_add(s, size);
|
---|
2433 | read(fd, ptr, size);
|
---|
2434 | } else {
|
---|
2435 | s->data_offset += size;
|
---|
2436 | }
|
---|
2437 | next: ;
|
---|
2438 | }
|
---|
2439 |
|
---|
2440 | /* gr relocate stab strings */
|
---|
2441 | if (stab_index && stabstr_index) {
|
---|
2442 | Stab_Sym *a, *b;
|
---|
2443 | unsigned o;
|
---|
2444 | s = sm_table[stab_index].s;
|
---|
2445 | a = (Stab_Sym *)(s->data + sm_table[stab_index].offset);
|
---|
2446 | b = (Stab_Sym *)(s->data + s->data_offset);
|
---|
2447 | o = sm_table[stabstr_index].offset;
|
---|
2448 | while (a < b)
|
---|
2449 | a->n_strx += o, a++;
|
---|
2450 | }
|
---|
2451 |
|
---|
2452 | /* second short pass to update sh_link and sh_info fields of new
|
---|
2453 | sections */
|
---|
2454 | for(i = 1; i < ehdr.e_shnum; i++) {
|
---|
2455 | s = sm_table[i].s;
|
---|
2456 | if (!s || !sm_table[i].new_section)
|
---|
2457 | continue;
|
---|
2458 | sh = &shdr[i];
|
---|
2459 | if (sh->sh_link > 0)
|
---|
2460 | s->link = sm_table[sh->sh_link].s;
|
---|
2461 | if (sh->sh_type == SHT_RELX) {
|
---|
2462 | s->sh_info = sm_table[sh->sh_info].s->sh_num;
|
---|
2463 | /* update backward link */
|
---|
2464 | s1->sections[s->sh_info]->reloc = s;
|
---|
2465 | }
|
---|
2466 | }
|
---|
2467 | sm = sm_table;
|
---|
2468 |
|
---|
2469 | /* resolve symbols */
|
---|
2470 | old_to_new_syms = tcc_mallocz(nb_syms * sizeof(int));
|
---|
2471 |
|
---|
2472 | sym = symtab + 1;
|
---|
2473 | for(i = 1; i < nb_syms; i++, sym++) {
|
---|
2474 | if (sym->st_shndx != SHN_UNDEF &&
|
---|
2475 | sym->st_shndx < SHN_LORESERVE) {
|
---|
2476 | sm = &sm_table[sym->st_shndx];
|
---|
2477 | if (sm->link_once) {
|
---|
2478 | /* if a symbol is in a link once section, we use the
|
---|
2479 | already defined symbol. It is very important to get
|
---|
2480 | correct relocations */
|
---|
2481 | if (ELFW(ST_BIND)(sym->st_info) != STB_LOCAL) {
|
---|
2482 | name = (char *) strtab + sym->st_name;
|
---|
2483 | sym_index = find_elf_sym(symtab_section, name);
|
---|
2484 | if (sym_index)
|
---|
2485 | old_to_new_syms[i] = sym_index;
|
---|
2486 | }
|
---|
2487 | continue;
|
---|
2488 | }
|
---|
2489 | /* if no corresponding section added, no need to add symbol */
|
---|
2490 | if (!sm->s)
|
---|
2491 | continue;
|
---|
2492 | /* convert section number */
|
---|
2493 | sym->st_shndx = sm->s->sh_num;
|
---|
2494 | /* offset value */
|
---|
2495 | sym->st_value += sm->offset;
|
---|
2496 | }
|
---|
2497 | /* add symbol */
|
---|
2498 | name = (char *) strtab + sym->st_name;
|
---|
2499 | sym_index = set_elf_sym(symtab_section, sym->st_value, sym->st_size,
|
---|
2500 | sym->st_info, sym->st_other,
|
---|
2501 | sym->st_shndx, name);
|
---|
2502 | old_to_new_syms[i] = sym_index;
|
---|
2503 | }
|
---|
2504 |
|
---|
2505 | /* third pass to patch relocation entries */
|
---|
2506 | for(i = 1; i < ehdr.e_shnum; i++) {
|
---|
2507 | s = sm_table[i].s;
|
---|
2508 | if (!s)
|
---|
2509 | continue;
|
---|
2510 | sh = &shdr[i];
|
---|
2511 | offset = sm_table[i].offset;
|
---|
2512 | switch(s->sh_type) {
|
---|
2513 | case SHT_RELX:
|
---|
2514 | /* take relocation offset information */
|
---|
2515 | offseti = sm_table[sh->sh_info].offset;
|
---|
2516 | for_each_elem(s, (offset / sizeof(*rel)), rel, ElfW_Rel) {
|
---|
2517 | int type;
|
---|
2518 | unsigned sym_index;
|
---|
2519 | /* convert symbol index */
|
---|
2520 | type = ELFW(R_TYPE)(rel->r_info);
|
---|
2521 | sym_index = ELFW(R_SYM)(rel->r_info);
|
---|
2522 | /* NOTE: only one symtab assumed */
|
---|
2523 | if (sym_index >= nb_syms)
|
---|
2524 | goto invalid_reloc;
|
---|
2525 | sym_index = old_to_new_syms[sym_index];
|
---|
2526 | /* ignore link_once in rel section. */
|
---|
2527 | if (!sym_index && !sm->link_once
|
---|
2528 | #ifdef TCC_TARGET_ARM
|
---|
2529 | && type != R_ARM_V4BX
|
---|
2530 | #endif
|
---|
2531 | ) {
|
---|
2532 | invalid_reloc:
|
---|
2533 | tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
|
---|
2534 | i, strsec + sh->sh_name, rel->r_offset);
|
---|
2535 | goto fail;
|
---|
2536 | }
|
---|
2537 | rel->r_info = ELFW(R_INFO)(sym_index, type);
|
---|
2538 | /* offset the relocation offset */
|
---|
2539 | rel->r_offset += offseti;
|
---|
2540 | #ifdef TCC_TARGET_ARM
|
---|
2541 | /* Jumps and branches from a Thumb code to a PLT entry need
|
---|
2542 | special handling since PLT entries are ARM code.
|
---|
2543 | Unconditional bl instructions referencing PLT entries are
|
---|
2544 | handled by converting these instructions into blx
|
---|
2545 | instructions. Other case of instructions referencing a PLT
|
---|
2546 | entry require to add a Thumb stub before the PLT entry to
|
---|
2547 | switch to ARM mode. We set bit plt_thumb_stub of the
|
---|
2548 | attribute of a symbol to indicate such a case. */
|
---|
2549 | if (type == R_ARM_THM_JUMP24)
|
---|
2550 | get_sym_attr(s1, sym_index, 1)->plt_thumb_stub = 1;
|
---|
2551 | #endif
|
---|
2552 | }
|
---|
2553 | break;
|
---|
2554 | default:
|
---|
2555 | break;
|
---|
2556 | }
|
---|
2557 | }
|
---|
2558 |
|
---|
2559 | ret = 0;
|
---|
2560 | the_end:
|
---|
2561 | tcc_free(symtab);
|
---|
2562 | tcc_free(strtab);
|
---|
2563 | tcc_free(old_to_new_syms);
|
---|
2564 | tcc_free(sm_table);
|
---|
2565 | tcc_free(strsec);
|
---|
2566 | tcc_free(shdr);
|
---|
2567 | return ret;
|
---|
2568 | }
|
---|
2569 |
|
---|
2570 | typedef struct ArchiveHeader {
|
---|
2571 | char ar_name[16]; /* name of this member */
|
---|
2572 | char ar_date[12]; /* file mtime */
|
---|
2573 | char ar_uid[6]; /* owner uid; printed as decimal */
|
---|
2574 | char ar_gid[6]; /* owner gid; printed as decimal */
|
---|
2575 | char ar_mode[8]; /* file mode, printed as octal */
|
---|
2576 | char ar_size[10]; /* file size, printed as decimal */
|
---|
2577 | char ar_fmag[2]; /* should contain ARFMAG */
|
---|
2578 | } ArchiveHeader;
|
---|
2579 |
|
---|
2580 | static int get_be32(const uint8_t *b)
|
---|
2581 | {
|
---|
2582 | return b[3] | (b[2] << 8) | (b[1] << 16) | (b[0] << 24);
|
---|
2583 | }
|
---|
2584 |
|
---|
2585 | static long get_be64(const uint8_t *b)
|
---|
2586 | {
|
---|
2587 | long long ret = get_be32(b);
|
---|
2588 | ret = (ret << 32) | (unsigned)get_be32(b+4);
|
---|
2589 | return (long)ret;
|
---|
2590 | }
|
---|
2591 |
|
---|
2592 | /* load only the objects which resolve undefined symbols */
|
---|
2593 | static int tcc_load_alacarte(TCCState *s1, int fd, int size, int entrysize)
|
---|
2594 | {
|
---|
2595 | long i, bound, nsyms, sym_index, off, ret;
|
---|
2596 | uint8_t *data;
|
---|
2597 | const char *ar_names, *p;
|
---|
2598 | const uint8_t *ar_index;
|
---|
2599 | ElfW(Sym) *sym;
|
---|
2600 |
|
---|
2601 | data = tcc_malloc(size);
|
---|
2602 | if (read(fd, data, size) != size)
|
---|
2603 | goto fail;
|
---|
2604 | nsyms = entrysize == 4 ? get_be32(data) : get_be64(data);
|
---|
2605 | ar_index = data + entrysize;
|
---|
2606 | ar_names = (char *) ar_index + nsyms * entrysize;
|
---|
2607 |
|
---|
2608 | do {
|
---|
2609 | bound = 0;
|
---|
2610 | for(p = ar_names, i = 0; i < nsyms; i++, p += strlen(p)+1) {
|
---|
2611 | sym_index = find_elf_sym(symtab_section, p);
|
---|
2612 | if(sym_index) {
|
---|
2613 | sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
|
---|
2614 | if(sym->st_shndx == SHN_UNDEF) {
|
---|
2615 | off = (entrysize == 4
|
---|
2616 | ? get_be32(ar_index + i * 4)
|
---|
2617 | : get_be64(ar_index + i * 8))
|
---|
2618 | + sizeof(ArchiveHeader);
|
---|
2619 | ++bound;
|
---|
2620 | if(tcc_load_object_file(s1, fd, off) < 0) {
|
---|
2621 | fail:
|
---|
2622 | ret = -1;
|
---|
2623 | goto the_end;
|
---|
2624 | }
|
---|
2625 | }
|
---|
2626 | }
|
---|
2627 | }
|
---|
2628 | } while(bound);
|
---|
2629 | ret = 0;
|
---|
2630 | the_end:
|
---|
2631 | tcc_free(data);
|
---|
2632 | return ret;
|
---|
2633 | }
|
---|
2634 |
|
---|
2635 | /* load a '.a' file */
|
---|
2636 | ST_FUNC int tcc_load_archive(TCCState *s1, int fd)
|
---|
2637 | {
|
---|
2638 | ArchiveHeader hdr;
|
---|
2639 | char ar_size[11];
|
---|
2640 | char ar_name[17];
|
---|
2641 | char magic[8];
|
---|
2642 | int size, len, i;
|
---|
2643 | unsigned long file_offset;
|
---|
2644 |
|
---|
2645 | /* skip magic which was already checked */
|
---|
2646 | read(fd, magic, sizeof(magic));
|
---|
2647 |
|
---|
2648 | for(;;) {
|
---|
2649 | len = read(fd, &hdr, sizeof(hdr));
|
---|
2650 | if (len == 0)
|
---|
2651 | break;
|
---|
2652 | if (len != sizeof(hdr)) {
|
---|
2653 | tcc_error_noabort("invalid archive");
|
---|
2654 | return -1;
|
---|
2655 | }
|
---|
2656 | memcpy(ar_size, hdr.ar_size, sizeof(hdr.ar_size));
|
---|
2657 | ar_size[sizeof(hdr.ar_size)] = '\0';
|
---|
2658 | size = strtol(ar_size, NULL, 0);
|
---|
2659 | memcpy(ar_name, hdr.ar_name, sizeof(hdr.ar_name));
|
---|
2660 | for(i = sizeof(hdr.ar_name) - 1; i >= 0; i--) {
|
---|
2661 | if (ar_name[i] != ' ')
|
---|
2662 | break;
|
---|
2663 | }
|
---|
2664 | ar_name[i + 1] = '\0';
|
---|
2665 | file_offset = lseek(fd, 0, SEEK_CUR);
|
---|
2666 | /* align to even */
|
---|
2667 | size = (size + 1) & ~1;
|
---|
2668 | if (!strcmp(ar_name, "/")) {
|
---|
2669 | /* coff symbol table : we handle it */
|
---|
2670 | if(s1->alacarte_link)
|
---|
2671 | return tcc_load_alacarte(s1, fd, size, 4);
|
---|
2672 | } else if (!strcmp(ar_name, "/SYM64/")) {
|
---|
2673 | if(s1->alacarte_link)
|
---|
2674 | return tcc_load_alacarte(s1, fd, size, 8);
|
---|
2675 | } else {
|
---|
2676 | ElfW(Ehdr) ehdr;
|
---|
2677 | if (tcc_object_type(fd, &ehdr) == AFF_BINTYPE_REL) {
|
---|
2678 | if (tcc_load_object_file(s1, fd, file_offset) < 0)
|
---|
2679 | return -1;
|
---|
2680 | }
|
---|
2681 | }
|
---|
2682 | lseek(fd, file_offset + size, SEEK_SET);
|
---|
2683 | }
|
---|
2684 | return 0;
|
---|
2685 | }
|
---|
2686 |
|
---|
2687 | #ifndef TCC_TARGET_PE
|
---|
2688 | /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
|
---|
2689 | is referenced by the user (so it should be added as DT_NEEDED in
|
---|
2690 | the generated ELF file) */
|
---|
2691 | ST_FUNC int tcc_load_dll(TCCState *s1, int fd, const char *filename, int level)
|
---|
2692 | {
|
---|
2693 | ElfW(Ehdr) ehdr;
|
---|
2694 | ElfW(Shdr) *shdr, *sh, *sh1;
|
---|
2695 | int i, j, nb_syms, nb_dts, sym_bind, ret;
|
---|
2696 | ElfW(Sym) *sym, *dynsym;
|
---|
2697 | ElfW(Dyn) *dt, *dynamic;
|
---|
2698 | unsigned char *dynstr;
|
---|
2699 | const char *name, *soname;
|
---|
2700 | DLLReference *dllref;
|
---|
2701 |
|
---|
2702 | read(fd, &ehdr, sizeof(ehdr));
|
---|
2703 |
|
---|
2704 | /* test CPU specific stuff */
|
---|
2705 | if (ehdr.e_ident[5] != ELFDATA2LSB ||
|
---|
2706 | ehdr.e_machine != EM_TCC_TARGET) {
|
---|
2707 | tcc_error_noabort("bad architecture");
|
---|
2708 | return -1;
|
---|
2709 | }
|
---|
2710 |
|
---|
2711 | /* read sections */
|
---|
2712 | shdr = load_data(fd, ehdr.e_shoff, sizeof(ElfW(Shdr)) * ehdr.e_shnum);
|
---|
2713 |
|
---|
2714 | /* load dynamic section and dynamic symbols */
|
---|
2715 | nb_syms = 0;
|
---|
2716 | nb_dts = 0;
|
---|
2717 | dynamic = NULL;
|
---|
2718 | dynsym = NULL; /* avoid warning */
|
---|
2719 | dynstr = NULL; /* avoid warning */
|
---|
2720 | for(i = 0, sh = shdr; i < ehdr.e_shnum; i++, sh++) {
|
---|
2721 | switch(sh->sh_type) {
|
---|
2722 | case SHT_DYNAMIC:
|
---|
2723 | nb_dts = sh->sh_size / sizeof(ElfW(Dyn));
|
---|
2724 | dynamic = load_data(fd, sh->sh_offset, sh->sh_size);
|
---|
2725 | break;
|
---|
2726 | case SHT_DYNSYM:
|
---|
2727 | nb_syms = sh->sh_size / sizeof(ElfW(Sym));
|
---|
2728 | dynsym = load_data(fd, sh->sh_offset, sh->sh_size);
|
---|
2729 | sh1 = &shdr[sh->sh_link];
|
---|
2730 | dynstr = load_data(fd, sh1->sh_offset, sh1->sh_size);
|
---|
2731 | break;
|
---|
2732 | default:
|
---|
2733 | break;
|
---|
2734 | }
|
---|
2735 | }
|
---|
2736 |
|
---|
2737 | /* compute the real library name */
|
---|
2738 | soname = tcc_basename(filename);
|
---|
2739 |
|
---|
2740 | for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
|
---|
2741 | if (dt->d_tag == DT_SONAME) {
|
---|
2742 | soname = (char *) dynstr + dt->d_un.d_val;
|
---|
2743 | }
|
---|
2744 | }
|
---|
2745 |
|
---|
2746 | /* if the dll is already loaded, do not load it */
|
---|
2747 | for(i = 0; i < s1->nb_loaded_dlls; i++) {
|
---|
2748 | dllref = s1->loaded_dlls[i];
|
---|
2749 | if (!strcmp(soname, dllref->name)) {
|
---|
2750 | /* but update level if needed */
|
---|
2751 | if (level < dllref->level)
|
---|
2752 | dllref->level = level;
|
---|
2753 | ret = 0;
|
---|
2754 | goto the_end;
|
---|
2755 | }
|
---|
2756 | }
|
---|
2757 |
|
---|
2758 | /* add the dll and its level */
|
---|
2759 | dllref = tcc_mallocz(sizeof(DLLReference) + strlen(soname));
|
---|
2760 | dllref->level = level;
|
---|
2761 | strcpy(dllref->name, soname);
|
---|
2762 | dynarray_add(&s1->loaded_dlls, &s1->nb_loaded_dlls, dllref);
|
---|
2763 |
|
---|
2764 | /* add dynamic symbols in dynsym_section */
|
---|
2765 | for(i = 1, sym = dynsym + 1; i < nb_syms; i++, sym++) {
|
---|
2766 | sym_bind = ELFW(ST_BIND)(sym->st_info);
|
---|
2767 | if (sym_bind == STB_LOCAL)
|
---|
2768 | continue;
|
---|
2769 | name = (char *) dynstr + sym->st_name;
|
---|
2770 | set_elf_sym(s1->dynsymtab_section, sym->st_value, sym->st_size,
|
---|
2771 | sym->st_info, sym->st_other, sym->st_shndx, name);
|
---|
2772 | }
|
---|
2773 |
|
---|
2774 | /* load all referenced DLLs */
|
---|
2775 | for(i = 0, dt = dynamic; i < nb_dts; i++, dt++) {
|
---|
2776 | switch(dt->d_tag) {
|
---|
2777 | case DT_NEEDED:
|
---|
2778 | name = (char *) dynstr + dt->d_un.d_val;
|
---|
2779 | for(j = 0; j < s1->nb_loaded_dlls; j++) {
|
---|
2780 | dllref = s1->loaded_dlls[j];
|
---|
2781 | if (!strcmp(name, dllref->name))
|
---|
2782 | goto already_loaded;
|
---|
2783 | }
|
---|
2784 | if (tcc_add_dll(s1, name, AFF_REFERENCED_DLL) < 0) {
|
---|
2785 | tcc_error_noabort("referenced dll '%s' not found", name);
|
---|
2786 | ret = -1;
|
---|
2787 | goto the_end;
|
---|
2788 | }
|
---|
2789 | already_loaded:
|
---|
2790 | break;
|
---|
2791 | }
|
---|
2792 | }
|
---|
2793 | ret = 0;
|
---|
2794 | the_end:
|
---|
2795 | tcc_free(dynstr);
|
---|
2796 | tcc_free(dynsym);
|
---|
2797 | tcc_free(dynamic);
|
---|
2798 | tcc_free(shdr);
|
---|
2799 | return ret;
|
---|
2800 | }
|
---|
2801 |
|
---|
2802 | #define LD_TOK_NAME 256
|
---|
2803 | #define LD_TOK_EOF (-1)
|
---|
2804 |
|
---|
2805 | /* return next ld script token */
|
---|
2806 | static int ld_next(TCCState *s1, char *name, int name_size)
|
---|
2807 | {
|
---|
2808 | int c;
|
---|
2809 | char *q;
|
---|
2810 |
|
---|
2811 | redo:
|
---|
2812 | switch(ch) {
|
---|
2813 | case ' ':
|
---|
2814 | case '\t':
|
---|
2815 | case '\f':
|
---|
2816 | case '\v':
|
---|
2817 | case '\r':
|
---|
2818 | case '\n':
|
---|
2819 | inp();
|
---|
2820 | goto redo;
|
---|
2821 | case '/':
|
---|
2822 | minp();
|
---|
2823 | if (ch == '*') {
|
---|
2824 | file->buf_ptr = parse_comment(file->buf_ptr);
|
---|
2825 | ch = file->buf_ptr[0];
|
---|
2826 | goto redo;
|
---|
2827 | } else {
|
---|
2828 | q = name;
|
---|
2829 | *q++ = '/';
|
---|
2830 | goto parse_name;
|
---|
2831 | }
|
---|
2832 | break;
|
---|
2833 | case '\\':
|
---|
2834 | ch = handle_eob();
|
---|
2835 | if (ch != '\\')
|
---|
2836 | goto redo;
|
---|
2837 | /* fall through */
|
---|
2838 | /* case 'a' ... 'z': */
|
---|
2839 | case 'a':
|
---|
2840 | case 'b':
|
---|
2841 | case 'c':
|
---|
2842 | case 'd':
|
---|
2843 | case 'e':
|
---|
2844 | case 'f':
|
---|
2845 | case 'g':
|
---|
2846 | case 'h':
|
---|
2847 | case 'i':
|
---|
2848 | case 'j':
|
---|
2849 | case 'k':
|
---|
2850 | case 'l':
|
---|
2851 | case 'm':
|
---|
2852 | case 'n':
|
---|
2853 | case 'o':
|
---|
2854 | case 'p':
|
---|
2855 | case 'q':
|
---|
2856 | case 'r':
|
---|
2857 | case 's':
|
---|
2858 | case 't':
|
---|
2859 | case 'u':
|
---|
2860 | case 'v':
|
---|
2861 | case 'w':
|
---|
2862 | case 'x':
|
---|
2863 | case 'y':
|
---|
2864 | case 'z':
|
---|
2865 | /* case 'A' ... 'z': */
|
---|
2866 | case 'A':
|
---|
2867 | case 'B':
|
---|
2868 | case 'C':
|
---|
2869 | case 'D':
|
---|
2870 | case 'E':
|
---|
2871 | case 'F':
|
---|
2872 | case 'G':
|
---|
2873 | case 'H':
|
---|
2874 | case 'I':
|
---|
2875 | case 'J':
|
---|
2876 | case 'K':
|
---|
2877 | case 'L':
|
---|
2878 | case 'M':
|
---|
2879 | case 'N':
|
---|
2880 | case 'O':
|
---|
2881 | case 'P':
|
---|
2882 | case 'Q':
|
---|
2883 | case 'R':
|
---|
2884 | case 'S':
|
---|
2885 | case 'T':
|
---|
2886 | case 'U':
|
---|
2887 | case 'V':
|
---|
2888 | case 'W':
|
---|
2889 | case 'X':
|
---|
2890 | case 'Y':
|
---|
2891 | case 'Z':
|
---|
2892 | case '_':
|
---|
2893 | case '.':
|
---|
2894 | case '$':
|
---|
2895 | case '~':
|
---|
2896 | q = name;
|
---|
2897 | parse_name:
|
---|
2898 | for(;;) {
|
---|
2899 | if (!((ch >= 'a' && ch <= 'z') ||
|
---|
2900 | (ch >= 'A' && ch <= 'Z') ||
|
---|
2901 | (ch >= '0' && ch <= '9') ||
|
---|
2902 | strchr("/.-_+=$:\\,~", ch)))
|
---|
2903 | break;
|
---|
2904 | if ((q - name) < name_size - 1) {
|
---|
2905 | *q++ = ch;
|
---|
2906 | }
|
---|
2907 | minp();
|
---|
2908 | }
|
---|
2909 | *q = '\0';
|
---|
2910 | c = LD_TOK_NAME;
|
---|
2911 | break;
|
---|
2912 | case CH_EOF:
|
---|
2913 | c = LD_TOK_EOF;
|
---|
2914 | break;
|
---|
2915 | default:
|
---|
2916 | c = ch;
|
---|
2917 | inp();
|
---|
2918 | break;
|
---|
2919 | }
|
---|
2920 | return c;
|
---|
2921 | }
|
---|
2922 |
|
---|
2923 | static int ld_add_file(TCCState *s1, const char filename[])
|
---|
2924 | {
|
---|
2925 | if (filename[0] == '/') {
|
---|
2926 | if (CONFIG_SYSROOT[0] == '\0'
|
---|
2927 | && tcc_add_file_internal(s1, filename, AFF_TYPE_BIN) == 0)
|
---|
2928 | return 0;
|
---|
2929 | filename = tcc_basename(filename);
|
---|
2930 | }
|
---|
2931 | return tcc_add_dll(s1, filename, 0);
|
---|
2932 | }
|
---|
2933 |
|
---|
2934 | static inline int new_undef_syms(void)
|
---|
2935 | {
|
---|
2936 | int ret = 0;
|
---|
2937 | ret = new_undef_sym;
|
---|
2938 | new_undef_sym = 0;
|
---|
2939 | return ret;
|
---|
2940 | }
|
---|
2941 |
|
---|
2942 | static int ld_add_file_list(TCCState *s1, const char *cmd, int as_needed)
|
---|
2943 | {
|
---|
2944 | char filename[1024], libname[1024];
|
---|
2945 | int t, group, nblibs = 0, ret = 0;
|
---|
2946 | char **libs = NULL;
|
---|
2947 |
|
---|
2948 | group = !strcmp(cmd, "GROUP");
|
---|
2949 | if (!as_needed)
|
---|
2950 | new_undef_syms();
|
---|
2951 | t = ld_next(s1, filename, sizeof(filename));
|
---|
2952 | if (t != '(')
|
---|
2953 | expect("(");
|
---|
2954 | t = ld_next(s1, filename, sizeof(filename));
|
---|
2955 | for(;;) {
|
---|
2956 | libname[0] = '\0';
|
---|
2957 | if (t == LD_TOK_EOF) {
|
---|
2958 | tcc_error_noabort("unexpected end of file");
|
---|
2959 | ret = -1;
|
---|
2960 | goto lib_parse_error;
|
---|
2961 | } else if (t == ')') {
|
---|
2962 | break;
|
---|
2963 | } else if (t == '-') {
|
---|
2964 | t = ld_next(s1, filename, sizeof(filename));
|
---|
2965 | if ((t != LD_TOK_NAME) || (filename[0] != 'l')) {
|
---|
2966 | tcc_error_noabort("library name expected");
|
---|
2967 | ret = -1;
|
---|
2968 | goto lib_parse_error;
|
---|
2969 | }
|
---|
2970 | pstrcpy(libname, sizeof libname, &filename[1]);
|
---|
2971 | if (s1->static_link) {
|
---|
2972 | snprintf(filename, sizeof filename, "lib%s.a", libname);
|
---|
2973 | } else {
|
---|
2974 | snprintf(filename, sizeof filename, "lib%s.so", libname);
|
---|
2975 | }
|
---|
2976 | } else if (t != LD_TOK_NAME) {
|
---|
2977 | tcc_error_noabort("filename expected");
|
---|
2978 | ret = -1;
|
---|
2979 | goto lib_parse_error;
|
---|
2980 | }
|
---|
2981 | if (!strcmp(filename, "AS_NEEDED")) {
|
---|
2982 | ret = ld_add_file_list(s1, cmd, 1);
|
---|
2983 | if (ret)
|
---|
2984 | goto lib_parse_error;
|
---|
2985 | } else {
|
---|
2986 | /* TODO: Implement AS_NEEDED support. Ignore it for now */
|
---|
2987 | if (!as_needed) {
|
---|
2988 | ret = ld_add_file(s1, filename);
|
---|
2989 | if (ret)
|
---|
2990 | goto lib_parse_error;
|
---|
2991 | if (group) {
|
---|
2992 | /* Add the filename *and* the libname to avoid future conversions */
|
---|
2993 | dynarray_add(&libs, &nblibs, tcc_strdup(filename));
|
---|
2994 | if (libname[0] != '\0')
|
---|
2995 | dynarray_add(&libs, &nblibs, tcc_strdup(libname));
|
---|
2996 | }
|
---|
2997 | }
|
---|
2998 | }
|
---|
2999 | t = ld_next(s1, filename, sizeof(filename));
|
---|
3000 | if (t == ',') {
|
---|
3001 | t = ld_next(s1, filename, sizeof(filename));
|
---|
3002 | }
|
---|
3003 | }
|
---|
3004 | if (group && !as_needed) {
|
---|
3005 | while (new_undef_syms()) {
|
---|
3006 | int i;
|
---|
3007 |
|
---|
3008 | for (i = 0; i < nblibs; i ++)
|
---|
3009 | ld_add_file(s1, libs[i]);
|
---|
3010 | }
|
---|
3011 | }
|
---|
3012 | lib_parse_error:
|
---|
3013 | dynarray_reset(&libs, &nblibs);
|
---|
3014 | return ret;
|
---|
3015 | }
|
---|
3016 |
|
---|
3017 | /* interpret a subset of GNU ldscripts to handle the dummy libc.so
|
---|
3018 | files */
|
---|
3019 | ST_FUNC int tcc_load_ldscript(TCCState *s1)
|
---|
3020 | {
|
---|
3021 | char cmd[64];
|
---|
3022 | char filename[1024];
|
---|
3023 | int t, ret;
|
---|
3024 |
|
---|
3025 | ch = handle_eob();
|
---|
3026 | for(;;) {
|
---|
3027 | t = ld_next(s1, cmd, sizeof(cmd));
|
---|
3028 | if (t == LD_TOK_EOF)
|
---|
3029 | return 0;
|
---|
3030 | else if (t != LD_TOK_NAME)
|
---|
3031 | return -1;
|
---|
3032 | if (!strcmp(cmd, "INPUT") ||
|
---|
3033 | !strcmp(cmd, "GROUP")) {
|
---|
3034 | ret = ld_add_file_list(s1, cmd, 0);
|
---|
3035 | if (ret)
|
---|
3036 | return ret;
|
---|
3037 | } else if (!strcmp(cmd, "OUTPUT_FORMAT") ||
|
---|
3038 | !strcmp(cmd, "TARGET")) {
|
---|
3039 | /* ignore some commands */
|
---|
3040 | t = ld_next(s1, cmd, sizeof(cmd));
|
---|
3041 | if (t != '(')
|
---|
3042 | expect("(");
|
---|
3043 | for(;;) {
|
---|
3044 | t = ld_next(s1, filename, sizeof(filename));
|
---|
3045 | if (t == LD_TOK_EOF) {
|
---|
3046 | tcc_error_noabort("unexpected end of file");
|
---|
3047 | return -1;
|
---|
3048 | } else if (t == ')') {
|
---|
3049 | break;
|
---|
3050 | }
|
---|
3051 | }
|
---|
3052 | } else {
|
---|
3053 | return -1;
|
---|
3054 | }
|
---|
3055 | }
|
---|
3056 | return 0;
|
---|
3057 | }
|
---|
3058 | #endif /* !TCC_TARGET_PE */
|
---|