source: asp3_tinet_ecnl_arm/trunk/musl-1.1.18/src/stdio/tempnam.c@ 352

#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/stat.h>
#include <limits.h>
#include <string.h>
#include "syscall.h"

#define MAXTRIES 100

char *__randname(char *);

char *tempnam(const char *dir, const char *pfx)
{
        char s[PATH_MAX];
        size_t l, dl, pl;
        int try;
        int r;

        if (!dir) dir = P_tmpdir;
        if (!pfx) pfx = "temp";

        dl = strlen(dir);
        pl = strlen(pfx);
        l = dl + 1 + pl + 1 + 6;

        if (l >= PATH_MAX) {
                errno = ENAMETOOLONG;
                return 0;
        }

        memcpy(s, dir, dl);
        s[dl] = '/';
        memcpy(s+dl+1, pfx, pl);
        s[dl+1+pl] = '_';
        s[l] = 0;

        for (try=0; try<MAXTRIES; try++) {
                __randname(s+l-6);
#ifdef SYS_lstat
                r = __syscall(SYS_lstat, s, &(struct stat){0});
#else
                r = __syscall(SYS_fstatat, AT_FDCWD, s,
                        &(struct stat){0}, AT_SYMLINK_NOFOLLOW);
#endif
                if (r == -ENOENT) return strdup(s);
        }
        return 0;
}