lib/sh/mailstat.c

   1 /* mailstat.c -- stat a mailbox file, handling maildir-type mail directories */
   2
   3 /* Copyright (C) 2001 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Bash, the Bourne Again SHell.
   6
   7    Bash is free software; you can redistribute it and/or modify it under
   8    the terms of the GNU General Public License as published by the Free
   9    Software Foundation; either version 2, or (at your option) any later
  10    version.
  11
  12    Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  13    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15    for more details.
  16
  17    You should have received a copy of the GNU General Public License along
  18    with Bash; see the file COPYING.  If not, write to the Free Software
  19    Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
  20
  21 #include <config.h>
  22
  23 #include <stdio.h>
  24 #include <errno.h>
  25
  26 #include <bashtypes.h>
  27 #include <posixstat.h>
  28 #include <posixdir.h>
  29 #include <bashansi.h>
  30
  31 #ifndef _MINIX
  32 #  include <sys/param.h>
  33 #endif
  34
  35 #include <maxpath.h>
  36
  37 /*
  38  *     Stat a file. If it's a maildir, check all messages
  39  *     in the maildir and present the grand total as a file.
  40  *     The fields in the 'struct stat' are from the mail directory.
  41  *     The following fields are emulated:
  42  *
  43  *     st_nlink always 1, unless st_blocks is not present, in which case it's
  44  *              the total number of messages
  45  *     st_size   total number of bytes in all files
  46  *     st_blocks       total number of messages, if present in struct stat
  47  *     st_atime access time of newest file in maildir
  48  *     st_mtime modify time of newest file in maildir
  49  *     st_mode   S_IFDIR changed to S_IFREG
  50  *
  51  *     This is good enough for most mail-checking applications.
  52  */
  53
  54 int
  55 mailstat(path, st)
  56      const char *path;
  57      struct stat *st;
  58 {
  59   static struct stat st_new_last, st_ret_last;
  60   struct stat st_ret, st_tmp;
  61   DIR *dd;
  62   struct dirent *fn;
  63   char dir[PATH_MAX * 2], file[PATH_MAX * 2];
  64   int i, l;
  65   time_t atime, mtime;
  66
  67   atime = mtime = 0;
  68
  69   /* First see if it's a directory. */
  70   if ((i = stat(path, st)) != 0 || S_ISDIR(st->st_mode) == 0)
  71     return i;
  72
  73   if (strlen(path) > sizeof(dir) - 5)
  74     {
  75 #ifdef ENAMETOOLONG
  76       errno = ENAMETOOLONG;
  77 #else
  78       errno = EINVAL;
  79 #endif
  80       return -1;
  81     }
  82
  83   st_ret = *st;
  84   st_ret.st_nlink = 1;
  85   st_ret.st_size  = 0;
  86 #ifdef HAVE_STRUCT_STAT_ST_BLOCKS
  87   st_ret.st_blocks  = 0;
  88 #else
  89   st_ret.st_nlink = 0;
  90 #endif
  91   st_ret.st_mode  &= ~S_IFDIR;
  92   st_ret.st_mode  |= S_IFREG;
  93
  94   /* See if cur/ is present */
  95   sprintf(dir, "%s/cur", path);
  96   if (stat(dir, &st_tmp) || S_ISDIR(st_tmp.st_mode) == 0)
  97     return 0;
  98   st_ret.st_atime = st_tmp.st_atime;
  99
 100   /* See if tmp/ is present */
 101   sprintf(dir, "%s/tmp", path);
 102   if (stat(dir, &st_tmp) || S_ISDIR(st_tmp.st_mode) == 0)
 103     return 0;
 104   st_ret.st_mtime = st_tmp.st_mtime;
 105
 106   /* And new/ */
 107   sprintf(dir, "%s/new", path);
 108   if (stat(dir, &st_tmp) || S_ISDIR(st_tmp.st_mode) == 0)
 109     return 0;
 110   st_ret.st_mtime = st_tmp.st_mtime;
 111
 112   /* Optimization - if new/ didn't change, nothing else did. */
 113   if (st_tmp.st_dev == st_new_last.st_dev &&
 114       st_tmp.st_ino == st_new_last.st_ino &&
 115       st_tmp.st_atime == st_new_last.st_atime &&
 116       st_tmp.st_mtime == st_new_last.st_mtime)
 117     {
 118       *st = st_ret_last;
 119       return 0;
 120     }
 121   st_new_last = st_tmp;
 122
 123   /* Loop over new/ and cur/ */
 124   for (i = 0; i < 2; i++)
 125     {
 126       sprintf(dir, "%s/%s", path, i ? "cur" : "new");
 127       sprintf(file, "%s/", dir);
 128       l = strlen(file);
 129       if ((dd = opendir(dir)) == NULL)
 130         return 0;
 131       while ((fn = readdir(dd)) != NULL)
 132         {
 133           if (fn->d_name[0] == '.' || strlen(fn->d_name) + l >= sizeof(file))
 134             continue;
 135           strcpy(file + l, fn->d_name);
 136           if (stat(file, &st_tmp) != 0)
 137             continue;
 138           st_ret.st_size += st_tmp.st_size;
 139 #ifdef HAVE_STRUCT_STAT_ST_BLOCKS
 140           st_ret.st_blocks++;
 141 #else
 142           st_ret.st_nlink++;
 143 #endif
 144           if (st_tmp.st_atime != st_tmp.st_mtime && st_tmp.st_atime > atime)
 145             atime = st_tmp.st_atime;
 146           if (st_tmp.st_mtime > mtime)
 147             mtime = st_tmp.st_mtime;
 148         }
 149       closedir(dd);
 150     }
 151
 152     if (atime)
 153       st_ret.st_atime = atime;
 154     if (mtime)
 155       st_ret.st_mtime = mtime;
 156
 157     *st = st_ret_last = st_ret;
 158     return 0;
 159 }