coreutils/df.c

   1 #include "internal.h"
   2 #include <stdio.h>
   3 #include <mntent.h>
   4 #include <sys/stat.h>
   5 #include <sys/vfs.h>
   6 #include <fstab.h>
   7
   8 const char      df_usage[] = "df [filesystem ...]\n"
   9 "\n"
  10 "\tPrint the filesystem space used and space available.\n";
  11
  12
  13 static int
  14 df(char* device, const char * mountPoint)
  15 {
  16         struct statfs   s;
  17         long            blocks_used;
  18         long            blocks_percent_used;
  19
  20         if ( statfs(mountPoint, &s) != 0 ) {
  21                 perror(mountPoint);
  22                 return 1;
  23         }
  24
  25         if ( s.f_blocks > 0 ) {
  26                 blocks_used = s.f_blocks - s.f_bfree;
  27                 blocks_percent_used = (long)
  28                  (blocks_used * 100.0 / (blocks_used + s.f_bavail) + 0.5);
  29                 if ( strcmp(device, "/dev/root")==0)
  30                     device=(getfsfile ("/"))->fs_spec;
  31
  32                 printf(
  33                        "%-20s %9ld %9ld %9ld %3ld%% %s\n",
  34                        device,
  35                        (long)(s.f_blocks * (s.f_bsize / 1024.0)),
  36                        (long)((s.f_blocks - s.f_bfree)  * (s.f_bsize / 1024.0)),
  37                        (long)(s.f_bavail * (s.f_bsize / 1024.0)),
  38                        blocks_percent_used,
  39                        mountPoint);
  40
  41         }
  42
  43         return 0;
  44 }
  45
  46 extern int
  47 df_main(int argc, char * * argv)
  48 {
  49         printf("%-20s %-14s %s %s %s %s\n", "Filesystem",
  50                 "1k-blocks", "Used", "Available", "Use%", "Mounted on");
  51
  52         if ( argc > 1 ) {
  53                 struct mntent*  mountEntry;
  54                 int             status;
  55
  56                 while ( argc > 1 ) {
  57                         if ( (mountEntry = findMountPoint(argv[1], "/proc/mounts")) == 0 )
  58                         {
  59                                 fprintf(stderr, "%s: can't find mount point.\n" ,argv[1]);
  60                                 return 1;
  61                         }
  62                         status = df(mountEntry->mnt_fsname, mountEntry->mnt_dir);
  63                         if ( status != 0 )
  64                                 return status;
  65                         argc--;
  66                         argv++;
  67                 }
  68                 return 0;
  69         }
  70         else {
  71                 FILE *          mountTable;
  72                 struct mntent * mountEntry;
  73
  74                 mountTable = setmntent("/proc/mounts", "r");
  75                 if ( mountTable == 0) {
  76                         perror("/proc/mounts");
  77                         exit( FALSE);
  78                 }
  79
  80                 while ( (mountEntry = getmntent (mountTable))) {
  81                         int status=df(mountEntry->mnt_fsname, mountEntry->mnt_dir);
  82                         if (status)
  83                                 return status;
  84                 }
  85                 endmntent(mountTable);
  86         }
  87
  88         return 0;
  89 }
  90
  91
  92
  93
  94 /*
  95  * Given a block device, find the mount table entry if that block device
  96  * is mounted.
  97  *
  98  * Given any other file (or directory), find the mount table entry for its
  99  * filesystem.
 100  */
 101 extern struct mntent *
 102 findMountPoint(const char* name, const char* table)
 103 {
 104         struct stat     s;
 105         dev_t                   mountDevice;
 106         FILE *                  mountTable;
 107         struct mntent * mountEntry;
 108
 109         if ( stat(name, &s) != 0 )
 110                 return 0;
 111
 112         if ( (s.st_mode & S_IFMT) == S_IFBLK )
 113                 mountDevice = s.st_rdev;
 114         else
 115                 mountDevice = s.st_dev;
 116
 117
 118         if ( (mountTable = setmntent(table, "r")) == 0 )
 119                 return 0;
 120
 121         while ( (mountEntry = getmntent(mountTable)) != 0 ) {
 122                 if ( strcmp(name, mountEntry->mnt_dir) == 0
 123                  || strcmp(name, mountEntry->mnt_fsname) == 0 ) /* String match. */
 124                         break;
 125                 if ( stat(mountEntry->mnt_fsname, &s) == 0
 126                  && s.st_rdev == mountDevice )  /* Match the device. */
 127                                 break;
 128                 if ( stat(mountEntry->mnt_dir, &s) == 0
 129                  && s.st_dev == mountDevice )   /* Match the directory's mount point. */
 130                         break;
 131         }
 132         endmntent(mountTable);
 133         return mountEntry;
 134 }
 135
 136