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 /*
  47  * Given a block device, find the mount table entry if that block device
  48  * is mounted.
  49  *
  50  * Given any other file (or directory), find the mount table entry for its
  51  * filesystem.
  52  */
  53 extern struct mntent *
  54 findMountPoint(const char* name, const char* table)
  55 {
  56         struct stat     s;
  57         dev_t                   mountDevice;
  58         FILE *                  mountTable;
  59         struct mntent * mountEntry;
  60
  61         if ( stat(name, &s) != 0 )
  62                 return 0;
  63
  64         if ( (s.st_mode & S_IFMT) == S_IFBLK )
  65                 mountDevice = s.st_rdev;
  66         else
  67                 mountDevice = s.st_dev;
  68
  69
  70         if ( (mountTable = setmntent(table, "r")) == 0 )
  71                 return 0;
  72
  73         while ( (mountEntry = getmntent(mountTable)) != 0 ) {
  74                 if ( strcmp(name, mountEntry->mnt_dir) == 0
  75                  || strcmp(name, mountEntry->mnt_fsname) == 0 ) /* String match. */
  76                         break;
  77                 if ( stat(mountEntry->mnt_fsname, &s) == 0
  78                  && s.st_rdev == mountDevice )  /* Match the device. */
  79                                 break;
  80                 if ( stat(mountEntry->mnt_dir, &s) == 0
  81                  && s.st_dev == mountDevice )   /* Match the directory's mount point. */
  82                         break;
  83         }
  84         endmntent(mountTable);
  85         return mountEntry;
  86 }
  87
  88
  89
  90 extern int
  91 df_main(int argc, char * * argv)
  92 {
  93         printf("%-20s %-14s %s %s %s %s\n", "Filesystem",
  94                 "1k-blocks", "Used", "Available", "Use%", "Mounted on");
  95
  96         if ( argc > 1 ) {
  97                 struct mntent*  mountEntry;
  98                 int             status;
  99
 100                 while ( argc > 1 ) {
 101                         if ( (mountEntry = findMountPoint(argv[1], "/proc/mounts")) == 0 )
 102                         {
 103                                 fprintf(stderr, "%s: can't find mount point.\n" ,argv[1]);
 104                                 return 1;
 105                         }
 106                         status = df(mountEntry->mnt_fsname, mountEntry->mnt_dir);
 107                         if ( status != 0 )
 108                                 return status;
 109                         argc--;
 110                         argv++;
 111                 }
 112                 return 0;
 113         }
 114         else {
 115                 FILE *          mountTable;
 116                 struct mntent * mountEntry;
 117
 118                 mountTable = setmntent("/proc/mounts", "r");
 119                 if ( mountTable == 0) {
 120                         perror("/proc/mounts");
 121                         exit( FALSE);
 122                 }
 123
 124                 while ( (mountEntry = getmntent (mountTable))) {
 125                         int status=df(mountEntry->mnt_fsname, mountEntry->mnt_dir);
 126                         if (status)
 127                                 return status;
 128                 }
 129                 endmntent(mountTable);
 130         }
 131
 132         return 0;
 133 }
 134
 135
 136