libc-top-half/musl/src/misc/mntent.c

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <mntent.h>
   4 #include <errno.h>
   5
   6 static char *internal_buf;
   7 static size_t internal_bufsize;
   8
   9 #define SENTINEL (char *)&internal_buf
  10
  11 FILE *setmntent(const char *name, const char *mode)
  12 {
  13         return fopen(name, mode);
  14 }
  15
  16 int endmntent(FILE *f)
  17 {
  18         if (f) fclose(f);
  19         return 1;
  20 }
  21
  22 struct mntent *getmntent_r(FILE *f, struct mntent *mnt, char *linebuf, int buflen)
  23 {
  24         int cnt, n[8], use_internal = (linebuf == SENTINEL);
  25
  26         mnt->mnt_freq = 0;
  27         mnt->mnt_passno = 0;
  28
  29         do {
  30                 if (use_internal) {
  31                         getline(&internal_buf, &internal_bufsize, f);
  32                         linebuf = internal_buf;
  33                 } else {
  34                         fgets(linebuf, buflen, f);
  35                 }
  36                 if (feof(f) || ferror(f)) return 0;
  37                 if (!strchr(linebuf, '\n')) {
  38                         fscanf(f, "%*[^\n]%*[\n]");
  39                         errno = ERANGE;
  40                         return 0;
  41                 }
  42                 cnt = sscanf(linebuf, " %n%*s%n %n%*s%n %n%*s%n %n%*s%n %d %d",
  43                         n, n+1, n+2, n+3, n+4, n+5, n+6, n+7,
  44                         &mnt->mnt_freq, &mnt->mnt_passno);
  45         } while (cnt < 2 || linebuf[n[0]] == '#');
  46
  47         linebuf[n[1]] = 0;
  48         linebuf[n[3]] = 0;
  49         linebuf[n[5]] = 0;
  50         linebuf[n[7]] = 0;
  51
  52         mnt->mnt_fsname = linebuf+n[0];
  53         mnt->mnt_dir = linebuf+n[2];
  54         mnt->mnt_type = linebuf+n[4];
  55         mnt->mnt_opts = linebuf+n[6];
  56
  57         return mnt;
  58 }
  59
  60 struct mntent *getmntent(FILE *f)
  61 {
  62         static struct mntent mnt;
  63         return getmntent_r(f, &mnt, SENTINEL, 0);
  64 }
  65
  66 int addmntent(FILE *f, const struct mntent *mnt)
  67 {
  68         if (fseek(f, 0, SEEK_END)) return 1;
  69         return fprintf(f, "%s\t%s\t%s\t%s\t%d\t%d\n",
  70                 mnt->mnt_fsname, mnt->mnt_dir, mnt->mnt_type, mnt->mnt_opts,
  71                 mnt->mnt_freq, mnt->mnt_passno) < 0;
  72 }
  73
  74 char *hasmntopt(const struct mntent *mnt, const char *opt)
  75 {
  76         return strstr(mnt->mnt_opts, opt);
  77 }