source3/smbd/dfree.c

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