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 extern int DEBUGLEVEL;
  26
  27 /****************************************************************************
  28 normalise for DOS usage
  29 ****************************************************************************/
  30 static void disk_norm(BOOL small_query, SMB_BIG_UINT *bsize,SMB_BIG_UINT *dfree,SMB_BIG_UINT *dsize)
  31 {
  32         /* check if the disk is beyond the max disk size */
  33         SMB_BIG_UINT maxdisksize = lp_maxdisksize();
  34         if (maxdisksize) {
  35                 /* convert to blocks - and don't overflow */
  36                 maxdisksize = ((maxdisksize*1024)/(*bsize))*1024;
  37                 if (*dsize > maxdisksize) *dsize = maxdisksize;
  38                 if (*dfree > maxdisksize) *dfree = maxdisksize-1;
  39                 /* the -1 should stop applications getting div by 0
  40                    errors */
  41         }
  42
  43         while (*dfree > WORDMAX || *dsize > WORDMAX || *bsize < 512) {
  44                 *dfree /= 2;
  45                 *dsize /= 2;
  46                 *bsize *= 2;
  47                 if(small_query) {
  48                         /*
  49                          * Force max to fit in 16 bit fields.
  50                          */
  51                         if (*bsize > (WORDMAX*512)) {
  52                                 *bsize = (WORDMAX*512);
  53                                 if (*dsize > WORDMAX)
  54                                         *dsize = WORDMAX;
  55                                 if (*dfree >  WORDMAX)
  56                                         *dfree = WORDMAX;
  57                                 break;
  58                         }
  59                 }
  60         }
  61 }
  62
  63
  64
  65 /****************************************************************************
  66   return number of 1K blocks available on a path and total number
  67 ****************************************************************************/
  68
  69 static SMB_BIG_UINT disk_free(char *path, BOOL small_query,
  70                               SMB_BIG_UINT *bsize,SMB_BIG_UINT *dfree,SMB_BIG_UINT *dsize)
  71 {
  72         int dfree_retval;
  73         SMB_BIG_UINT dfree_q = 0;
  74         SMB_BIG_UINT bsize_q = 0;
  75         SMB_BIG_UINT dsize_q = 0;
  76         char *dfree_command;
  77
  78         (*dfree) = (*dsize) = 0;
  79         (*bsize) = 512;
  80
  81         /*
  82          * If external disk calculation specified, use it.
  83          */
  84
  85         dfree_command = lp_dfree_command();
  86         if (dfree_command && *dfree_command) {
  87                 char *p;
  88                 char **lines;
  89                 pstring syscmd;
  90
  91                 slprintf(syscmd, sizeof(syscmd), "%s %s", dfree_command, path);
  92                 DEBUG (3, ("disk_free: Running command %s\n", syscmd));
  93
  94                 lines = file_lines_pload(syscmd, NULL);
  95                 if (lines) {
  96                         char *line = lines[0];
  97                         if (strlen(line) > 0)
  98                                 line[strlen(line)-1] = '\0';
  99
 100                         DEBUG (3, ("Read input from dfree, \"%s\"\n", line));
 101
 102                         *dsize = (SMB_BIG_UINT)strtoul(line, &p, 10);
 103                         while (p && *p & isspace(*p))
 104                                 p++;
 105                         if (p && *p)
 106                                 *dfree = (SMB_BIG_UINT)strtoul(p, &p, 10);
 107                         while (p && *p & isspace(*p))
 108                                 p++;
 109                         if (p && *p)
 110                                 *bsize = (SMB_BIG_UINT)strtoul(p, NULL, 10);
 111                         else
 112                                 *bsize = 1024;
 113                         file_lines_free(lines);
 114                         DEBUG (3, ("Parsed output of dfree, dsize=%u, dfree=%u, bsize=%u\n",
 115                                 (unsigned int)*dsize, (unsigned int)*dfree, (unsigned int)*bsize));
 116
 117                         if (!*dsize)
 118                                 *dsize = 2048;
 119                         if (!*dfree)
 120                                 *dfree = 1024;
 121                 } else {
 122                         DEBUG (0, ("disk_free: sys_popen() failed for command %s. Error was : %s\n",
 123                                 syscmd, strerror(errno) ));
 124                         sys_fsusage(path, dfree, dsize);
 125                 }
 126         } else
 127                 sys_fsusage(path, dfree, dsize);
 128
 129         if (disk_quotas(path, &bsize_q, &dfree_q, &dsize_q)) {
 130                 (*bsize) = bsize_q;
 131                 (*dfree) = MIN(*dfree,dfree_q);
 132                 (*dsize) = MIN(*dsize,dsize_q);
 133         }
 134
 135         /* FIXME : Any reason for this assumption ? */
 136         if (*bsize < 256) {
 137                 DEBUG(5,("disk_free:Warning: bsize == %d < 256 . Changing to assumed correct bsize = 512\n",(int)*bsize));
 138                 *bsize = 512;
 139         }
 140
 141         if ((*dsize)<1) {
 142                 static int done;
 143                 if (!done) {
 144                         DEBUG(0,("WARNING: dfree is broken on this system\n"));
 145                         done=1;
 146                 }
 147                 *dsize = 20*1024*1024/(*bsize);
 148                 *dfree = MAX(1,*dfree);
 149         }
 150
 151         disk_norm(small_query,bsize,dfree,dsize);
 152
 153         if ((*bsize) < 1024) {
 154                 dfree_retval = (*dfree)/(1024/(*bsize));
 155         } else {
 156                 dfree_retval = ((*bsize)/1024)*(*dfree);
 157         }
 158
 159         return(dfree_retval);
 160 }
 161
 162
 163 /****************************************************************************
 164 wrap it to get filenames right
 165 ****************************************************************************/
 166 SMB_BIG_UINT sys_disk_free(char *path, BOOL small_query,
 167                            SMB_BIG_UINT *bsize,SMB_BIG_UINT *dfree,SMB_BIG_UINT *dsize)
 168 {
 169         return(disk_free(dos_to_unix(path,False),small_query, bsize,dfree,dsize));
 170 }