source/smbd/dfree.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    functions to calculate the free disk space
   5    Copyright (C) Andrew Tridgell 1998
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 /****************************************************************************
  25 normalise for DOS usage
  26 ****************************************************************************/
  27 static void disk_norm(BOOL small_query, SMB_BIG_UINT *bsize,SMB_BIG_UINT *dfree,SMB_BIG_UINT *dsize)
  28 {
  29         /* check if the disk is beyond the max disk size */
  30         SMB_BIG_UINT maxdisksize = lp_maxdisksize();
  31         if (maxdisksize) {
  32                 /* convert to blocks - and don't overflow */
  33                 maxdisksize = ((maxdisksize*1024)/(*bsize))*1024;
  34                 if (*dsize > maxdisksize) *dsize = maxdisksize;
  35                 if (*dfree > maxdisksize) *dfree = maxdisksize-1;
  36                 /* the -1 should stop applications getting div by 0
  37                    errors */
  38         }
  39
  40         while (*dfree > WORDMAX || *dsize > WORDMAX || *bsize < 512) {
  41                 *dfree /= 2;
  42                 *dsize /= 2;
  43                 *bsize *= 2;
  44                 if(small_query) {
  45                         /*
  46                          * Force max to fit in 16 bit fields.
  47                          */
  48                         if (*bsize > (WORDMAX*512)) {
  49                                 *bsize = (WORDMAX*512);
  50                                 if (*dsize > WORDMAX)
  51                                         *dsize = WORDMAX;
  52                                 if (*dfree >  WORDMAX)
  53                                         *dfree = WORDMAX;
  54                                 break;
  55                         }
  56                 }
  57         }
  58 }
  59
  60
  61
  62 /****************************************************************************
  63   return number of 1K blocks available on a path and total number
  64 ****************************************************************************/
  65
  66 static SMB_BIG_UINT disk_free(const char *path, BOOL small_query,
  67                               SMB_BIG_UINT *bsize,SMB_BIG_UINT *dfree,SMB_BIG_UINT *dsize)
  68 {
  69         int dfree_retval;
  70         SMB_BIG_UINT dfree_q = 0;
  71         SMB_BIG_UINT bsize_q = 0;
  72         SMB_BIG_UINT dsize_q = 0;
  73         char *dfree_command;
  74
  75         (*dfree) = (*dsize) = 0;
  76         (*bsize) = 512;
  77
  78         /*
  79          * If external disk calculation specified, use it.
  80          */
  81
  82         dfree_command = lp_dfree_command();
  83         if (dfree_command && *dfree_command) {
  84                 char *p;
  85                 char **lines;
  86                 pstring syscmd;
  87
  88                 slprintf(syscmd, sizeof(syscmd)-1, "%s %s", dfree_command, path);
  89                 DEBUG (3, ("disk_free: Running command %s\n", syscmd));
  90
  91                 lines = file_lines_pload(syscmd, NULL);
  92                 if (lines) {
  93                         char *line = lines[0];
  94
  95                         DEBUG (3, ("Read input from dfree, \"%s\"\n", line));
  96
  97                         *dsize = (SMB_BIG_UINT)strtoul(line, &p, 10);
  98                         while (p && *p & isspace(*p))
  99                                 p++;
 100                         if (p && *p)
 101                                 *dfree = (SMB_BIG_UINT)strtoul(p, &p, 10);
 102                         while (p && *p & isspace(*p))
 103                                 p++;
 104                         if (p && *p)
 105                                 *bsize = (SMB_BIG_UINT)strtoul(p, NULL, 10);
 106                         else
 107                                 *bsize = 1024;
 108                         file_lines_free(lines);
 109                         DEBUG (3, ("Parsed output of dfree, dsize=%u, dfree=%u, bsize=%u\n",
 110                                 (unsigned int)*dsize, (unsigned int)*dfree, (unsigned int)*bsize));
 111
 112                         if (!*dsize)
 113                                 *dsize = 2048;
 114                         if (!*dfree)
 115                                 *dfree = 1024;
 116                 } else {
 117                         DEBUG (0, ("disk_free: sys_popen() failed for command %s. Error was : %s\n",
 118                                 syscmd, strerror(errno) ));
 119                         sys_fsusage(path, dfree, dsize);
 120                 }
 121         } else
 122                 sys_fsusage(path, dfree, dsize);
 123
 124         if (disk_quotas(path, &bsize_q, &dfree_q, &dsize_q)) {
 125                 (*bsize) = bsize_q;
 126                 (*dfree) = MIN(*dfree,dfree_q);
 127                 (*dsize) = MIN(*dsize,dsize_q);
 128         }
 129
 130         /* FIXME : Any reason for this assumption ? */
 131         if (*bsize < 256) {
 132                 DEBUG(5,("disk_free:Warning: bsize == %d < 256 . Changing to assumed correct bsize = 512\n",(int)*bsize));
 133                 *bsize = 512;
 134         }
 135
 136         if ((*dsize)<1) {
 137                 static int done;
 138                 if (!done) {
 139                         DEBUG(0,("WARNING: dfree is broken on this system\n"));
 140                         done=1;
 141                 }
 142                 *dsize = 20*1024*1024/(*bsize);
 143                 *dfree = MAX(1,*dfree);
 144         }
 145
 146         disk_norm(small_query,bsize,dfree,dsize);
 147
 148         if ((*bsize) < 1024) {
 149                 dfree_retval = (*dfree)/(1024/(*bsize));
 150         } else {
 151                 dfree_retval = ((*bsize)/1024)*(*dfree);
 152         }
 153
 154         return(dfree_retval);
 155 }
 156
 157
 158 /****************************************************************************
 159 wrap it to get filenames right
 160 ****************************************************************************/
 161 SMB_BIG_UINT sys_disk_free(const char *path, BOOL small_query,
 162                            SMB_BIG_UINT *bsize,SMB_BIG_UINT *dfree,SMB_BIG_UINT *dsize)
 163 {
 164         return disk_free(path,small_query, bsize,dfree,dsize);
 165 }