mount-deprecated/mount_mntent.c

   1 /* Private version of the libc *mntent() routines. */
   2 /* Note slightly different prototypes. */
   3
   4 /* 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@pld.ORG.PL>
   5  * - added Native Language Support
   6  */
   7
   8 #include <stdio.h>
   9 #include <string.h>             /* for index */
  10 #include <ctype.h>              /* for isdigit */
  11 #include <sys/stat.h>           /* for umask */
  12
  13 #include "mount_mntent.h"
  14 #include "sundries.h"           /* for xmalloc */
  15 #include "nls.h"
  16 #include "mangle.h"
  17 #include "closestream.h"
  18
  19 static int
  20 is_space_or_tab (char c) {
  21         return (c == ' ' || c == '\t');
  22 }
  23
  24 static char *
  25 skip_spaces(char *s) {
  26         while (is_space_or_tab(*s))
  27                 s++;
  28         return s;
  29 }
  30
  31 /*
  32  * fstat'ing the file and allocating a buffer holding all of it
  33  * may be a bad idea: if the file is /proc/mounts, the stat
  34  * returns 0.
  35  * (On the other hand, mangling and unmangling is meaningless
  36  *  for /proc/mounts.)
  37  */
  38
  39 mntFILE *
  40 my_setmntent (const char *file, char *mode) {
  41         mntFILE *mfp = xmalloc(sizeof(*mfp));
  42         mode_t old_umask = umask(077);
  43
  44         mfp->mntent_fp = fopen(file, mode);
  45         umask(old_umask);
  46         mfp->mntent_file = xstrdup(file);
  47         mfp->mntent_errs = (mfp->mntent_fp == NULL);
  48         mfp->mntent_softerrs = 0;
  49         mfp->mntent_lineno = 0;
  50         return mfp;
  51 }
  52
  53 void
  54 my_endmntent(mntFILE * mfp) {
  55         if (mfp) {
  56                 if (mfp->mntent_fp)
  57                         if (close_stream(mfp->mntent_fp))
  58                                 fprintf(stderr, _("write error"));
  59                 free(mfp->mntent_file);
  60                 free(mfp);
  61         }
  62 }
  63
  64 int
  65 my_addmntent (mntFILE *mfp, struct my_mntent *mnt) {
  66         char *m1, *m2, *m3, *m4;
  67         int res;
  68
  69         if (fseek (mfp->mntent_fp, 0, SEEK_END))
  70                 return 1;                       /* failure */
  71
  72         m1 = mangle(mnt->mnt_fsname);
  73         m2 = mangle(mnt->mnt_dir);
  74         m3 = mangle(mnt->mnt_type);
  75         m4 = mnt->mnt_opts ? mangle(mnt->mnt_opts) : "rw";
  76
  77         res = fprintf (mfp->mntent_fp, "%s %s %s %s %d %d\n",
  78                        m1, m2, m3, m4, mnt->mnt_freq, mnt->mnt_passno);
  79
  80         free(m1);
  81         free(m2);
  82         free(m3);
  83         if (mnt->mnt_opts)
  84                 free(m4);
  85         return (res < 0) ? 1 : 0;
  86 }
  87
  88 /* Read the next entry from the file fp. Stop reading at an incorrect entry. */
  89 struct my_mntent *
  90 my_getmntent (mntFILE *mfp) {
  91         static char buf[4096];
  92         static struct my_mntent me;
  93         char *s;
  94
  95  again:
  96         if (mfp->mntent_errs || mfp->mntent_softerrs >= ERR_MAX)
  97                 return NULL;
  98
  99         /* read the next non-blank non-comment line */
 100         do {
 101                 if (fgets (buf, sizeof(buf), mfp->mntent_fp) == NULL)
 102                         return NULL;
 103
 104                 mfp->mntent_lineno++;
 105                 s = strchr (buf, '\n');
 106                 if (s == NULL) {
 107                         /* Missing final newline?  Otherwise extremely */
 108                         /* long line - assume file was corrupted */
 109                         if (feof(mfp->mntent_fp)) {
 110                                 fprintf(stderr, _("[mntent]: warning: no final "
 111                                         "newline at the end of %s\n"),
 112                                         mfp->mntent_file);
 113                                 s = strchr (buf, 0);
 114                         } else {
 115                                 mfp->mntent_errs = 1;
 116                                 goto err;
 117                         }
 118                 }
 119                 *s = 0;
 120                 if (--s >= buf && *s == '\r')
 121                         *s = 0;
 122                 s = skip_spaces(buf);
 123         } while (*s == '\0' || *s == '#');
 124
 125         me.mnt_fsname = unmangle(s, &s);
 126         s = skip_spaces(s);
 127         me.mnt_dir = unmangle(s, &s);
 128         s = skip_spaces(s);
 129         me.mnt_type = unmangle(s, &s);
 130         s = skip_spaces(s);
 131         me.mnt_opts = unmangle(s, &s);
 132         s = skip_spaces(s);
 133
 134         if (!me.mnt_fsname || !me.mnt_dir || !me.mnt_type)
 135                 goto err;
 136
 137         if (isdigit(*s)) {
 138                 me.mnt_freq = atoi(s);
 139                 while(isdigit(*s)) s++;
 140         } else
 141                 me.mnt_freq = 0;
 142         if(*s && !is_space_or_tab(*s))
 143                 goto err;
 144
 145         s = skip_spaces(s);
 146         if(isdigit(*s)) {
 147                 me.mnt_passno = atoi(s);
 148                 while(isdigit(*s)) s++;
 149         } else
 150                 me.mnt_passno = 0;
 151         if(*s && !is_space_or_tab(*s))
 152                 goto err;
 153
 154         /* allow more stuff, e.g. comments, on this line */
 155
 156         return &me;
 157
 158  err:
 159         mfp->mntent_softerrs++;
 160         fprintf(stderr, _("[mntent]: line %d in %s is bad%s\n"),
 161                 mfp->mntent_lineno, mfp->mntent_file,
 162                 (mfp->mntent_errs || mfp->mntent_softerrs >= ERR_MAX) ?
 163                 _("; rest of file ignored") : "");
 164         goto again;
 165 }