[453] | 1 | /* gzread.c -- zlib functions for reading gzip files
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| 2 | * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013, 2016 Mark Adler
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| 3 | * For conditions of distribution and use, see copyright notice in zlib.h
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| 4 | */
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| 5 |
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| 6 | #include "gzguts.h"
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| 7 |
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| 8 | /* Local functions */
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| 9 | local int gz_load OF((gz_statep, unsigned char *, unsigned, unsigned *));
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| 10 | local int gz_avail OF((gz_statep));
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| 11 | local int gz_look OF((gz_statep));
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| 12 | local int gz_decomp OF((gz_statep));
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| 13 | local int gz_fetch OF((gz_statep));
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| 14 | local int gz_skip OF((gz_statep, z_off64_t));
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| 15 | local z_size_t gz_read OF((gz_statep, voidp, z_size_t));
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| 16 |
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| 17 | /* Use read() to load a buffer -- return -1 on error, otherwise 0. Read from
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| 18 | state->fd, and update state->eof, state->err, and state->msg as appropriate.
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| 19 | This function needs to loop on read(), since read() is not guaranteed to
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| 20 | read the number of bytes requested, depending on the type of descriptor. */
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| 21 | local int gz_load(state, buf, len, have)
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| 22 | gz_statep state;
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| 23 | unsigned char *buf;
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| 24 | unsigned len;
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| 25 | unsigned *have;
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| 26 | {
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| 27 | int ret;
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| 28 | unsigned get, max = ((unsigned)-1 >> 2) + 1;
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| 29 |
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| 30 | *have = 0;
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| 31 | do {
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| 32 | get = len - *have;
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| 33 | if (get > max)
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| 34 | get = max;
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| 35 | ret = read(state->fd, buf + *have, get);
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| 36 | if (ret <= 0)
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| 37 | break;
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| 38 | *have += (unsigned)ret;
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| 39 | } while (*have < len);
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| 40 | if (ret < 0) {
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| 41 | gz_error(state, Z_ERRNO, zstrerror());
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| 42 | return -1;
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| 43 | }
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| 44 | if (ret == 0)
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| 45 | state->eof = 1;
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| 46 | return 0;
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| 47 | }
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| 48 |
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| 49 | /* Load up input buffer and set eof flag if last data loaded -- return -1 on
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| 50 | error, 0 otherwise. Note that the eof flag is set when the end of the input
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| 51 | file is reached, even though there may be unused data in the buffer. Once
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| 52 | that data has been used, no more attempts will be made to read the file.
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| 53 | If strm->avail_in != 0, then the current data is moved to the beginning of
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| 54 | the input buffer, and then the remainder of the buffer is loaded with the
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| 55 | available data from the input file. */
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| 56 | local int gz_avail(state)
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| 57 | gz_statep state;
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| 58 | {
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| 59 | unsigned got;
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| 60 | z_streamp strm = &(state->strm);
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| 61 |
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| 62 | if (state->err != Z_OK && state->err != Z_BUF_ERROR)
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| 63 | return -1;
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| 64 | if (state->eof == 0) {
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| 65 | if (strm->avail_in) { /* copy what's there to the start */
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| 66 | unsigned char *p = state->in;
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| 67 | unsigned const char *q = strm->next_in;
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| 68 | unsigned n = strm->avail_in;
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| 69 | do {
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| 70 | *p++ = *q++;
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| 71 | } while (--n);
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| 72 | }
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| 73 | if (gz_load(state, state->in + strm->avail_in,
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| 74 | state->size - strm->avail_in, &got) == -1)
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| 75 | return -1;
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| 76 | strm->avail_in += got;
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| 77 | strm->next_in = state->in;
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| 78 | }
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| 79 | return 0;
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| 80 | }
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| 81 |
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| 82 | /* Look for gzip header, set up for inflate or copy. state->x.have must be 0.
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| 83 | If this is the first time in, allocate required memory. state->how will be
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| 84 | left unchanged if there is no more input data available, will be set to COPY
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| 85 | if there is no gzip header and direct copying will be performed, or it will
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| 86 | be set to GZIP for decompression. If direct copying, then leftover input
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| 87 | data from the input buffer will be copied to the output buffer. In that
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| 88 | case, all further file reads will be directly to either the output buffer or
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| 89 | a user buffer. If decompressing, the inflate state will be initialized.
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| 90 | gz_look() will return 0 on success or -1 on failure. */
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| 91 | local int gz_look(state)
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| 92 | gz_statep state;
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| 93 | {
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| 94 | z_streamp strm = &(state->strm);
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| 95 |
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| 96 | /* allocate read buffers and inflate memory */
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| 97 | if (state->size == 0) {
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| 98 | /* allocate buffers */
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| 99 | state->in = (unsigned char *)malloc(state->want);
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| 100 | state->out = (unsigned char *)malloc(state->want << 1);
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| 101 | if (state->in == NULL || state->out == NULL) {
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| 102 | free(state->out);
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| 103 | free(state->in);
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| 104 | gz_error(state, Z_MEM_ERROR, "out of memory");
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| 105 | return -1;
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| 106 | }
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| 107 | state->size = state->want;
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| 108 |
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| 109 | /* allocate inflate memory */
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| 110 | state->strm.zalloc = Z_NULL;
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| 111 | state->strm.zfree = Z_NULL;
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| 112 | state->strm.opaque = Z_NULL;
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| 113 | state->strm.avail_in = 0;
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| 114 | state->strm.next_in = Z_NULL;
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| 115 | if (inflateInit2(&(state->strm), 15 + 16) != Z_OK) { /* gunzip */
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| 116 | free(state->out);
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| 117 | free(state->in);
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| 118 | state->size = 0;
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| 119 | gz_error(state, Z_MEM_ERROR, "out of memory");
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| 120 | return -1;
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| 121 | }
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| 122 | }
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| 123 |
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| 124 | /* get at least the magic bytes in the input buffer */
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| 125 | if (strm->avail_in < 2) {
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| 126 | if (gz_avail(state) == -1)
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| 127 | return -1;
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| 128 | if (strm->avail_in == 0)
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| 129 | return 0;
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| 130 | }
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| 131 |
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| 132 | /* look for gzip magic bytes -- if there, do gzip decoding (note: there is
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| 133 | a logical dilemma here when considering the case of a partially written
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| 134 | gzip file, to wit, if a single 31 byte is written, then we cannot tell
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| 135 | whether this is a single-byte file, or just a partially written gzip
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| 136 | file -- for here we assume that if a gzip file is being written, then
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| 137 | the header will be written in a single operation, so that reading a
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| 138 | single byte is sufficient indication that it is not a gzip file) */
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| 139 | if (strm->avail_in > 1 &&
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| 140 | strm->next_in[0] == 31 && strm->next_in[1] == 139) {
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| 141 | inflateReset(strm);
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| 142 | state->how = GZIP;
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| 143 | state->direct = 0;
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| 144 | return 0;
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| 145 | }
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| 146 |
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| 147 | /* no gzip header -- if we were decoding gzip before, then this is trailing
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| 148 | garbage. Ignore the trailing garbage and finish. */
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| 149 | if (state->direct == 0) {
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| 150 | strm->avail_in = 0;
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| 151 | state->eof = 1;
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| 152 | state->x.have = 0;
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| 153 | return 0;
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| 154 | }
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| 155 |
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| 156 | /* doing raw i/o, copy any leftover input to output -- this assumes that
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| 157 | the output buffer is larger than the input buffer, which also assures
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| 158 | space for gzungetc() */
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| 159 | state->x.next = state->out;
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| 160 | if (strm->avail_in) {
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| 161 | memcpy(state->x.next, strm->next_in, strm->avail_in);
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| 162 | state->x.have = strm->avail_in;
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| 163 | strm->avail_in = 0;
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| 164 | }
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| 165 | state->how = COPY;
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| 166 | state->direct = 1;
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| 167 | return 0;
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| 168 | }
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| 169 |
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| 170 | /* Decompress from input to the provided next_out and avail_out in the state.
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| 171 | On return, state->x.have and state->x.next point to the just decompressed
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| 172 | data. If the gzip stream completes, state->how is reset to LOOK to look for
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| 173 | the next gzip stream or raw data, once state->x.have is depleted. Returns 0
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| 174 | on success, -1 on failure. */
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| 175 | local int gz_decomp(state)
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| 176 | gz_statep state;
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| 177 | {
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| 178 | int ret = Z_OK;
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| 179 | unsigned had;
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| 180 | z_streamp strm = &(state->strm);
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| 181 |
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| 182 | /* fill output buffer up to end of deflate stream */
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| 183 | had = strm->avail_out;
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| 184 | do {
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| 185 | /* get more input for inflate() */
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| 186 | if (strm->avail_in == 0 && gz_avail(state) == -1)
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| 187 | return -1;
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| 188 | if (strm->avail_in == 0) {
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| 189 | gz_error(state, Z_BUF_ERROR, "unexpected end of file");
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| 190 | break;
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| 191 | }
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| 192 |
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| 193 | /* decompress and handle errors */
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| 194 | ret = inflate(strm, Z_NO_FLUSH);
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| 195 | if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) {
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| 196 | gz_error(state, Z_STREAM_ERROR,
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| 197 | "internal error: inflate stream corrupt");
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| 198 | return -1;
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| 199 | }
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| 200 | if (ret == Z_MEM_ERROR) {
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| 201 | gz_error(state, Z_MEM_ERROR, "out of memory");
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| 202 | return -1;
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| 203 | }
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| 204 | if (ret == Z_DATA_ERROR) { /* deflate stream invalid */
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| 205 | gz_error(state, Z_DATA_ERROR,
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| 206 | strm->msg == NULL ? "compressed data error" : strm->msg);
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| 207 | return -1;
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| 208 | }
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| 209 | } while (strm->avail_out && ret != Z_STREAM_END);
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| 210 |
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| 211 | /* update available output */
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| 212 | state->x.have = had - strm->avail_out;
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| 213 | state->x.next = strm->next_out - state->x.have;
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| 214 |
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| 215 | /* if the gzip stream completed successfully, look for another */
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| 216 | if (ret == Z_STREAM_END)
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| 217 | state->how = LOOK;
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| 218 |
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| 219 | /* good decompression */
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| 220 | return 0;
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| 221 | }
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| 222 |
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| 223 | /* Fetch data and put it in the output buffer. Assumes state->x.have is 0.
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| 224 | Data is either copied from the input file or decompressed from the input
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| 225 | file depending on state->how. If state->how is LOOK, then a gzip header is
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| 226 | looked for to determine whether to copy or decompress. Returns -1 on error,
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| 227 | otherwise 0. gz_fetch() will leave state->how as COPY or GZIP unless the
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| 228 | end of the input file has been reached and all data has been processed. */
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| 229 | local int gz_fetch(state)
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| 230 | gz_statep state;
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| 231 | {
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| 232 | z_streamp strm = &(state->strm);
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| 233 |
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| 234 | do {
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| 235 | switch(state->how) {
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| 236 | case LOOK: /* -> LOOK, COPY (only if never GZIP), or GZIP */
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| 237 | if (gz_look(state) == -1)
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| 238 | return -1;
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| 239 | if (state->how == LOOK)
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| 240 | return 0;
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| 241 | break;
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| 242 | case COPY: /* -> COPY */
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| 243 | if (gz_load(state, state->out, state->size << 1, &(state->x.have))
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| 244 | == -1)
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| 245 | return -1;
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| 246 | state->x.next = state->out;
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| 247 | return 0;
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| 248 | case GZIP: /* -> GZIP or LOOK (if end of gzip stream) */
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| 249 | strm->avail_out = state->size << 1;
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| 250 | strm->next_out = state->out;
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| 251 | if (gz_decomp(state) == -1)
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| 252 | return -1;
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| 253 | }
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| 254 | } while (state->x.have == 0 && (!state->eof || strm->avail_in));
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| 255 | return 0;
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| 256 | }
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| 257 |
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| 258 | /* Skip len uncompressed bytes of output. Return -1 on error, 0 on success. */
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| 259 | local int gz_skip(state, len)
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| 260 | gz_statep state;
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| 261 | z_off64_t len;
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| 262 | {
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| 263 | unsigned n;
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| 264 |
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| 265 | /* skip over len bytes or reach end-of-file, whichever comes first */
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| 266 | while (len)
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| 267 | /* skip over whatever is in output buffer */
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| 268 | if (state->x.have) {
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| 269 | n = GT_OFF(state->x.have) || (z_off64_t)state->x.have > len ?
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| 270 | (unsigned)len : state->x.have;
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| 271 | state->x.have -= n;
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| 272 | state->x.next += n;
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| 273 | state->x.pos += n;
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| 274 | len -= n;
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| 275 | }
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| 276 |
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| 277 | /* output buffer empty -- return if we're at the end of the input */
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| 278 | else if (state->eof && state->strm.avail_in == 0)
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| 279 | break;
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| 280 |
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| 281 | /* need more data to skip -- load up output buffer */
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| 282 | else {
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| 283 | /* get more output, looking for header if required */
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| 284 | if (gz_fetch(state) == -1)
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| 285 | return -1;
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| 286 | }
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| 287 | return 0;
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| 288 | }
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| 289 |
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| 290 | /* Read len bytes into buf from file, or less than len up to the end of the
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| 291 | input. Return the number of bytes read. If zero is returned, either the
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| 292 | end of file was reached, or there was an error. state->err must be
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| 293 | consulted in that case to determine which. */
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| 294 | local z_size_t gz_read(state, buf, len)
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| 295 | gz_statep state;
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| 296 | voidp buf;
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| 297 | z_size_t len;
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| 298 | {
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| 299 | z_size_t got;
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| 300 | unsigned n;
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| 301 |
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| 302 | /* if len is zero, avoid unnecessary operations */
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| 303 | if (len == 0)
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| 304 | return 0;
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| 305 |
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| 306 | /* process a skip request */
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| 307 | if (state->seek) {
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| 308 | state->seek = 0;
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| 309 | if (gz_skip(state, state->skip) == -1)
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| 310 | return 0;
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| 311 | }
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| 312 |
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| 313 | /* get len bytes to buf, or less than len if at the end */
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| 314 | got = 0;
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| 315 | do {
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| 316 | /* set n to the maximum amount of len that fits in an unsigned int */
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| 317 | n = -1;
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| 318 | if (n > len)
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| 319 | n = len;
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| 320 |
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| 321 | /* first just try copying data from the output buffer */
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| 322 | if (state->x.have) {
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| 323 | if (state->x.have < n)
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| 324 | n = state->x.have;
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| 325 | memcpy(buf, state->x.next, n);
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| 326 | state->x.next += n;
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| 327 | state->x.have -= n;
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| 328 | }
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| 329 |
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| 330 | /* output buffer empty -- return if we're at the end of the input */
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| 331 | else if (state->eof && state->strm.avail_in == 0) {
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| 332 | state->past = 1; /* tried to read past end */
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| 333 | break;
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| 334 | }
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| 335 |
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| 336 | /* need output data -- for small len or new stream load up our output
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| 337 | buffer */
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| 338 | else if (state->how == LOOK || n < (state->size << 1)) {
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| 339 | /* get more output, looking for header if required */
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| 340 | if (gz_fetch(state) == -1)
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| 341 | return 0;
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| 342 | continue; /* no progress yet -- go back to copy above */
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| 343 | /* the copy above assures that we will leave with space in the
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| 344 | output buffer, allowing at least one gzungetc() to succeed */
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| 345 | }
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| 346 |
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| 347 | /* large len -- read directly into user buffer */
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| 348 | else if (state->how == COPY) { /* read directly */
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| 349 | if (gz_load(state, (unsigned char *)buf, n, &n) == -1)
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| 350 | return 0;
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| 351 | }
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| 352 |
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| 353 | /* large len -- decompress directly into user buffer */
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| 354 | else { /* state->how == GZIP */
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| 355 | state->strm.avail_out = n;
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| 356 | state->strm.next_out = (unsigned char *)buf;
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| 357 | if (gz_decomp(state) == -1)
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| 358 | return 0;
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| 359 | n = state->x.have;
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| 360 | state->x.have = 0;
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| 361 | }
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| 362 |
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| 363 | /* update progress */
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| 364 | len -= n;
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| 365 | buf = (char *)buf + n;
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| 366 | got += n;
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| 367 | state->x.pos += n;
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| 368 | } while (len);
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| 369 |
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| 370 | /* return number of bytes read into user buffer */
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| 371 | return got;
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| 372 | }
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| 373 |
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| 374 | /* -- see zlib.h -- */
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| 375 | int ZEXPORT gzread(file, buf, len)
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| 376 | gzFile file;
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| 377 | voidp buf;
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| 378 | unsigned len;
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| 379 | {
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| 380 | gz_statep state;
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| 381 |
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| 382 | /* get internal structure */
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| 383 | if (file == NULL)
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| 384 | return -1;
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| 385 | state = (gz_statep)file;
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| 386 |
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| 387 | /* check that we're reading and that there's no (serious) error */
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| 388 | if (state->mode != GZ_READ ||
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| 389 | (state->err != Z_OK && state->err != Z_BUF_ERROR))
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| 390 | return -1;
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| 391 |
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| 392 | /* since an int is returned, make sure len fits in one, otherwise return
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| 393 | with an error (this avoids a flaw in the interface) */
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| 394 | if ((int)len < 0) {
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| 395 | gz_error(state, Z_STREAM_ERROR, "request does not fit in an int");
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| 396 | return -1;
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| 397 | }
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| 398 |
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| 399 | /* read len or fewer bytes to buf */
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| 400 | len = gz_read(state, buf, len);
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| 401 |
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| 402 | /* check for an error */
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| 403 | if (len == 0 && state->err != Z_OK && state->err != Z_BUF_ERROR)
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| 404 | return -1;
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| 405 |
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| 406 | /* return the number of bytes read (this is assured to fit in an int) */
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| 407 | return (int)len;
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| 408 | }
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| 409 |
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| 410 | /* -- see zlib.h -- */
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| 411 | z_size_t ZEXPORT gzfread(buf, size, nitems, file)
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| 412 | voidp buf;
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| 413 | z_size_t size;
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| 414 | z_size_t nitems;
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| 415 | gzFile file;
|
---|
| 416 | {
|
---|
| 417 | z_size_t len;
|
---|
| 418 | gz_statep state;
|
---|
| 419 |
|
---|
| 420 | /* get internal structure */
|
---|
| 421 | if (file == NULL)
|
---|
| 422 | return 0;
|
---|
| 423 | state = (gz_statep)file;
|
---|
| 424 |
|
---|
| 425 | /* check that we're reading and that there's no (serious) error */
|
---|
| 426 | if (state->mode != GZ_READ ||
|
---|
| 427 | (state->err != Z_OK && state->err != Z_BUF_ERROR))
|
---|
| 428 | return 0;
|
---|
| 429 |
|
---|
| 430 | /* compute bytes to read -- error on overflow */
|
---|
| 431 | len = nitems * size;
|
---|
| 432 | if (size && len / size != nitems) {
|
---|
| 433 | gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t");
|
---|
| 434 | return 0;
|
---|
| 435 | }
|
---|
| 436 |
|
---|
| 437 | /* read len or fewer bytes to buf, return the number of full items read */
|
---|
| 438 | return len ? gz_read(state, buf, len) / size : 0;
|
---|
| 439 | }
|
---|
| 440 |
|
---|
| 441 | /* -- see zlib.h -- */
|
---|
| 442 | #ifdef Z_PREFIX_SET
|
---|
| 443 | # undef z_gzgetc
|
---|
| 444 | #else
|
---|
| 445 | # undef gzgetc
|
---|
| 446 | #endif
|
---|
| 447 | int ZEXPORT gzgetc(file)
|
---|
| 448 | gzFile file;
|
---|
| 449 | {
|
---|
| 450 | int ret;
|
---|
| 451 | unsigned char buf[1];
|
---|
| 452 | gz_statep state;
|
---|
| 453 |
|
---|
| 454 | /* get internal structure */
|
---|
| 455 | if (file == NULL)
|
---|
| 456 | return -1;
|
---|
| 457 | state = (gz_statep)file;
|
---|
| 458 |
|
---|
| 459 | /* check that we're reading and that there's no (serious) error */
|
---|
| 460 | if (state->mode != GZ_READ ||
|
---|
| 461 | (state->err != Z_OK && state->err != Z_BUF_ERROR))
|
---|
| 462 | return -1;
|
---|
| 463 |
|
---|
| 464 | /* try output buffer (no need to check for skip request) */
|
---|
| 465 | if (state->x.have) {
|
---|
| 466 | state->x.have--;
|
---|
| 467 | state->x.pos++;
|
---|
| 468 | return *(state->x.next)++;
|
---|
| 469 | }
|
---|
| 470 |
|
---|
| 471 | /* nothing there -- try gz_read() */
|
---|
| 472 | ret = gz_read(state, buf, 1);
|
---|
| 473 | return ret < 1 ? -1 : buf[0];
|
---|
| 474 | }
|
---|
| 475 |
|
---|
| 476 | int ZEXPORT gzgetc_(file)
|
---|
| 477 | gzFile file;
|
---|
| 478 | {
|
---|
| 479 | return gzgetc(file);
|
---|
| 480 | }
|
---|
| 481 |
|
---|
| 482 | /* -- see zlib.h -- */
|
---|
| 483 | int ZEXPORT gzungetc(c, file)
|
---|
| 484 | int c;
|
---|
| 485 | gzFile file;
|
---|
| 486 | {
|
---|
| 487 | gz_statep state;
|
---|
| 488 |
|
---|
| 489 | /* get internal structure */
|
---|
| 490 | if (file == NULL)
|
---|
| 491 | return -1;
|
---|
| 492 | state = (gz_statep)file;
|
---|
| 493 |
|
---|
| 494 | /* check that we're reading and that there's no (serious) error */
|
---|
| 495 | if (state->mode != GZ_READ ||
|
---|
| 496 | (state->err != Z_OK && state->err != Z_BUF_ERROR))
|
---|
| 497 | return -1;
|
---|
| 498 |
|
---|
| 499 | /* process a skip request */
|
---|
| 500 | if (state->seek) {
|
---|
| 501 | state->seek = 0;
|
---|
| 502 | if (gz_skip(state, state->skip) == -1)
|
---|
| 503 | return -1;
|
---|
| 504 | }
|
---|
| 505 |
|
---|
| 506 | /* can't push EOF */
|
---|
| 507 | if (c < 0)
|
---|
| 508 | return -1;
|
---|
| 509 |
|
---|
| 510 | /* if output buffer empty, put byte at end (allows more pushing) */
|
---|
| 511 | if (state->x.have == 0) {
|
---|
| 512 | state->x.have = 1;
|
---|
| 513 | state->x.next = state->out + (state->size << 1) - 1;
|
---|
| 514 | state->x.next[0] = (unsigned char)c;
|
---|
| 515 | state->x.pos--;
|
---|
| 516 | state->past = 0;
|
---|
| 517 | return c;
|
---|
| 518 | }
|
---|
| 519 |
|
---|
| 520 | /* if no room, give up (must have already done a gzungetc()) */
|
---|
| 521 | if (state->x.have == (state->size << 1)) {
|
---|
| 522 | gz_error(state, Z_DATA_ERROR, "out of room to push characters");
|
---|
| 523 | return -1;
|
---|
| 524 | }
|
---|
| 525 |
|
---|
| 526 | /* slide output data if needed and insert byte before existing data */
|
---|
| 527 | if (state->x.next == state->out) {
|
---|
| 528 | unsigned char *src = state->out + state->x.have;
|
---|
| 529 | unsigned char *dest = state->out + (state->size << 1);
|
---|
| 530 | while (src > state->out)
|
---|
| 531 | *--dest = *--src;
|
---|
| 532 | state->x.next = dest;
|
---|
| 533 | }
|
---|
| 534 | state->x.have++;
|
---|
| 535 | state->x.next--;
|
---|
| 536 | state->x.next[0] = (unsigned char)c;
|
---|
| 537 | state->x.pos--;
|
---|
| 538 | state->past = 0;
|
---|
| 539 | return c;
|
---|
| 540 | }
|
---|
| 541 |
|
---|
| 542 | /* -- see zlib.h -- */
|
---|
| 543 | char * ZEXPORT gzgets(file, buf, len)
|
---|
| 544 | gzFile file;
|
---|
| 545 | char *buf;
|
---|
| 546 | int len;
|
---|
| 547 | {
|
---|
| 548 | unsigned left, n;
|
---|
| 549 | char *str;
|
---|
| 550 | unsigned char *eol;
|
---|
| 551 | gz_statep state;
|
---|
| 552 |
|
---|
| 553 | /* check parameters and get internal structure */
|
---|
| 554 | if (file == NULL || buf == NULL || len < 1)
|
---|
| 555 | return NULL;
|
---|
| 556 | state = (gz_statep)file;
|
---|
| 557 |
|
---|
| 558 | /* check that we're reading and that there's no (serious) error */
|
---|
| 559 | if (state->mode != GZ_READ ||
|
---|
| 560 | (state->err != Z_OK && state->err != Z_BUF_ERROR))
|
---|
| 561 | return NULL;
|
---|
| 562 |
|
---|
| 563 | /* process a skip request */
|
---|
| 564 | if (state->seek) {
|
---|
| 565 | state->seek = 0;
|
---|
| 566 | if (gz_skip(state, state->skip) == -1)
|
---|
| 567 | return NULL;
|
---|
| 568 | }
|
---|
| 569 |
|
---|
| 570 | /* copy output bytes up to new line or len - 1, whichever comes first --
|
---|
| 571 | append a terminating zero to the string (we don't check for a zero in
|
---|
| 572 | the contents, let the user worry about that) */
|
---|
| 573 | str = buf;
|
---|
| 574 | left = (unsigned)len - 1;
|
---|
| 575 | if (left) do {
|
---|
| 576 | /* assure that something is in the output buffer */
|
---|
| 577 | if (state->x.have == 0 && gz_fetch(state) == -1)
|
---|
| 578 | return NULL; /* error */
|
---|
| 579 | if (state->x.have == 0) { /* end of file */
|
---|
| 580 | state->past = 1; /* read past end */
|
---|
| 581 | break; /* return what we have */
|
---|
| 582 | }
|
---|
| 583 |
|
---|
| 584 | /* look for end-of-line in current output buffer */
|
---|
| 585 | n = state->x.have > left ? left : state->x.have;
|
---|
| 586 | eol = (unsigned char *)memchr(state->x.next, '\n', n);
|
---|
| 587 | if (eol != NULL)
|
---|
| 588 | n = (unsigned)(eol - state->x.next) + 1;
|
---|
| 589 |
|
---|
| 590 | /* copy through end-of-line, or remainder if not found */
|
---|
| 591 | memcpy(buf, state->x.next, n);
|
---|
| 592 | state->x.have -= n;
|
---|
| 593 | state->x.next += n;
|
---|
| 594 | state->x.pos += n;
|
---|
| 595 | left -= n;
|
---|
| 596 | buf += n;
|
---|
| 597 | } while (left && eol == NULL);
|
---|
| 598 |
|
---|
| 599 | /* return terminated string, or if nothing, end of file */
|
---|
| 600 | if (buf == str)
|
---|
| 601 | return NULL;
|
---|
| 602 | buf[0] = 0;
|
---|
| 603 | return str;
|
---|
| 604 | }
|
---|
| 605 |
|
---|
| 606 | /* -- see zlib.h -- */
|
---|
| 607 | int ZEXPORT gzdirect(file)
|
---|
| 608 | gzFile file;
|
---|
| 609 | {
|
---|
| 610 | gz_statep state;
|
---|
| 611 |
|
---|
| 612 | /* get internal structure */
|
---|
| 613 | if (file == NULL)
|
---|
| 614 | return 0;
|
---|
| 615 | state = (gz_statep)file;
|
---|
| 616 |
|
---|
| 617 | /* if the state is not known, but we can find out, then do so (this is
|
---|
| 618 | mainly for right after a gzopen() or gzdopen()) */
|
---|
| 619 | if (state->mode == GZ_READ && state->how == LOOK && state->x.have == 0)
|
---|
| 620 | (void)gz_look(state);
|
---|
| 621 |
|
---|
| 622 | /* return 1 if transparent, 0 if processing a gzip stream */
|
---|
| 623 | return state->direct;
|
---|
| 624 | }
|
---|
| 625 |
|
---|
| 626 | /* -- see zlib.h -- */
|
---|
| 627 | int ZEXPORT gzclose_r(file)
|
---|
| 628 | gzFile file;
|
---|
| 629 | {
|
---|
| 630 | int ret, err;
|
---|
| 631 | gz_statep state;
|
---|
| 632 |
|
---|
| 633 | /* get internal structure */
|
---|
| 634 | if (file == NULL)
|
---|
| 635 | return Z_STREAM_ERROR;
|
---|
| 636 | state = (gz_statep)file;
|
---|
| 637 |
|
---|
| 638 | /* check that we're reading */
|
---|
| 639 | if (state->mode != GZ_READ)
|
---|
| 640 | return Z_STREAM_ERROR;
|
---|
| 641 |
|
---|
| 642 | /* free memory and close file */
|
---|
| 643 | if (state->size) {
|
---|
| 644 | inflateEnd(&(state->strm));
|
---|
| 645 | free(state->out);
|
---|
| 646 | free(state->in);
|
---|
| 647 | }
|
---|
| 648 | err = state->err == Z_BUF_ERROR ? Z_BUF_ERROR : Z_OK;
|
---|
| 649 | gz_error(state, Z_OK, NULL);
|
---|
| 650 | free(state->path);
|
---|
| 651 | ret = close(state->fd);
|
---|
| 652 | free(state);
|
---|
| 653 | return ret ? Z_ERRNO : err;
|
---|
| 654 | }
|
---|