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
  28 static void disk_norm(BOOL small_query, SMB_BIG_UINT *bsize,SMB_BIG_UINT *dfree,SMB_BIG_UINT *dsize)
  29 {
  30         /* check if the disk is beyond the max disk size */
  31         SMB_BIG_UINT maxdisksize = lp_maxdisksize();
  32         if (maxdisksize) {
  33                 /* convert to blocks - and don't overflow */
  34                 maxdisksize = ((maxdisksize*1024)/(*bsize))*1024;
  35                 if (*dsize > maxdisksize) *dsize = maxdisksize;
  36                 if (*dfree > maxdisksize) *dfree = maxdisksize-1;
  37                 /* the -1 should stop applications getting div by 0
  38                    errors */
  39         }
  40
  41         while (*dfree > WORDMAX || *dsize > WORDMAX || *bsize < 512) {
  42                 *dfree /= 2;
  43                 *dsize /= 2;
  44                 *bsize *= 2;
  45                 if(small_query) {
  46                         /*
  47                          * Force max to fit in 16 bit fields.
  48                          */
  49                         if (*bsize > (WORDMAX*512)) {
  50                                 *bsize = (WORDMAX*512);
  51                                 if (*dsize > WORDMAX)
  52                                         *dsize = WORDMAX;
  53                                 if (*dfree >  WORDMAX)
  54                                         *dfree = WORDMAX;
  55                                 break;
  56                         }
  57                 }
  58         }
  59 }
  60
  61
  62
  63 /****************************************************************************
  64  Return number of 1K blocks available on a path and total number.
  65 ****************************************************************************/
  66
  67 static SMB_BIG_UINT disk_free(char *path, BOOL small_query,
  68                               SMB_BIG_UINT *bsize,SMB_BIG_UINT *dfree,SMB_BIG_UINT *dsize)
  69 {
  70         int dfree_retval;
  71         SMB_BIG_UINT dfree_q = 0;
  72         SMB_BIG_UINT bsize_q = 0;
  73         SMB_BIG_UINT dsize_q = 0;
  74         char *dfree_command;
  75
  76         (*dfree) = (*dsize) = 0;
  77         (*bsize) = 512;
  78
  79         /*
  80          * If external disk calculation specified, use it.
  81          */
  82
  83         dfree_command = lp_dfree_command();
  84         if (dfree_command && *dfree_command) {
  85                 char *p;
  86                 char **lines;
  87                 pstring syscmd;
  88
  89                 slprintf(syscmd, sizeof(syscmd)-1, "%s %s", dfree_command, path);
  90                 DEBUG (3, ("disk_free: Running command %s\n", syscmd));
  91
  92                 lines = file_lines_pload(syscmd, NULL, True);
  93                 if (lines) {
  94                         char *line = lines[0];
  95
  96                         DEBUG (3, ("Read input from dfree, \"%s\"\n", line));
  97
  98                         *dsize = (SMB_BIG_UINT)strtoul(line, &p, 10);
  99                         while (p && *p & isspace(*p))
 100                                 p++;
 101                         if (p && *p)
 102                                 *dfree = (SMB_BIG_UINT)strtoul(p, &p, 10);
 103                         while (p && *p & isspace(*p))
 104                                 p++;
 105                         if (p && *p)
 106                                 *bsize = (SMB_BIG_UINT)strtoul(p, NULL, 10);
 107                         else
 108                                 *bsize = 1024;
 109                         file_lines_free(lines);
 110                         DEBUG (3, ("Parsed output of dfree, dsize=%u, dfree=%u, bsize=%u\n",
 111                                 (unsigned int)*dsize, (unsigned int)*dfree, (unsigned int)*bsize));
 112
 113                         if (!*dsize)
 114                                 *dsize = 2048;
 115                         if (!*dfree)
 116                                 *dfree = 1024;
 117                 } else {
 118                         DEBUG (0, ("disk_free: sys_popen() failed for command %s. Error was : %s\n",
 119                                 syscmd, strerror(errno) ));
 120                         sys_fsusage(path, dfree, dsize);
 121                 }
 122         } else
 123                 sys_fsusage(path, dfree, dsize);
 124
 125         if (disk_quotas(path, &bsize_q, &dfree_q, &dsize_q)) {
 126                 (*bsize) = bsize_q;
 127                 (*dfree) = MIN(*dfree,dfree_q);
 128                 (*dsize) = MIN(*dsize,dsize_q);
 129         }
 130
 131         /* FIXME : Any reason for this assumption ? */
 132         if (*bsize < 256) {
 133                 DEBUG(5,("disk_free:Warning: bsize == %d < 256 . Changing to assumed correct bsize = 512\n",(int)*bsize));
 134                 *bsize = 512;
 135         }
 136
 137         if ((*dsize)<1) {
 138                 static int done;
 139                 if (!done) {
 140                         DEBUG(0,("WARNING: dfree is broken on this system\n"));
 141                         done=1;
 142                 }
 143                 *dsize = 20*1024*1024/(*bsize);
 144                 *dfree = MAX(1,*dfree);
 145         }
 146
 147         disk_norm(small_query,bsize,dfree,dsize);
 148
 149         if ((*bsize) < 1024) {
 150                 dfree_retval = (*dfree)/(1024/(*bsize));
 151         } else {
 152                 dfree_retval = ((*bsize)/1024)*(*dfree);
 153         }
 154
 155         return(dfree_retval);
 156 }
 157
 158 /****************************************************************************
 159  Wrap it to get filenames right.
 160 ****************************************************************************/
 161
 162 SMB_BIG_UINT sys_disk_free(const char *path, BOOL small_query,
 163                            SMB_BIG_UINT *bsize,SMB_BIG_UINT *dfree,SMB_BIG_UINT *dsize)
 164 {
 165         return(disk_free(dos_to_unix_static(path),small_query, bsize,dfree,dsize));
 166 }