libs/pbd/mountpoint.cc

   1 /*
   2     Copyright (C) 2002 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18     $Id$
  19 */
  20
  21 #include <cstdio>
  22 #include <cstring>
  23 #include <string>
  24 #include <cstring>
  25 #include <limits.h>
  26
  27 #include "pbd/mountpoint.h"
  28
  29 using std::string;
  30
  31 #ifdef WAF_BUILD
  32 #include "libpbd-config.h"
  33 #endif
  34
  35 #ifdef HAVE_GETMNTENT
  36 #include <mntent.h>
  37
  38 struct mntent_sorter {
  39     bool operator() (const mntent *a, const mntent *b) {
  40             return strcmp (a->mnt_dir, b->mnt_dir);
  41     }
  42 };
  43
  44 string
  45 mountpoint (string path)
  46 {
  47         FILE *mntf;
  48         mntent *mnt;
  49         unsigned int maxmatch = 0;
  50         unsigned int matchlen;
  51         const char *cpath = path.c_str();
  52         char best[PATH_MAX+1];
  53
  54         if ((mntf = setmntent ("/etc/mtab", "r")) == 0) {
  55                 return "";
  56         }
  57
  58         best[0] = '\0';
  59
  60         while ((mnt = getmntent (mntf))) {
  61                 unsigned int n;
  62
  63                 n = 0;
  64                 matchlen = 0;
  65
  66                 /* note: strcmp's semantics are not
  67                    strict enough to use for this.
  68                 */
  69
  70                 while (cpath[n] && mnt->mnt_dir[n]) {
  71                         if (cpath[n] != mnt->mnt_dir[n]) {
  72                                 break;
  73                         }
  74                         matchlen++;
  75                         n++;
  76                 }
  77
  78                 if (cpath[matchlen] == '\0') {
  79
  80                         endmntent (mntf);
  81                         return mnt->mnt_dir;
  82
  83                 } else {
  84
  85                         if (matchlen > maxmatch) {
  86                                 snprintf (best, sizeof(best), "%s", mnt->mnt_dir);
  87                                 maxmatch = matchlen;
  88                         }
  89                 }
  90         }
  91
  92         endmntent (mntf);
  93
  94         return best;
  95 }
  96
  97 #else // !HAVE_GETMNTENT
  98
  99 #include <sys/param.h>
 100 #include <sys/ucred.h>
 101 #include <sys/mount.h>
 102
 103 string
 104 mountpoint (string path)
 105 {
 106         struct statfs *mntbufp = 0;
 107         int count;
 108         unsigned int maxmatch = 0;
 109         unsigned int matchlen;
 110         const char *cpath = path.c_str();
 111         char best[PATH_MAX+1];
 112
 113         if ((count = getmntinfo(&mntbufp, MNT_NOWAIT)) == 0) {
 114                 free(mntbufp);
 115                 return "\0";
 116         }
 117
 118         best[0] = '\0';
 119
 120         for (int i = 0; i < count; ++i) {
 121                 unsigned int n = 0;
 122                 matchlen = 0;
 123
 124                 /* note: strcmp's semantics are not
 125                    strict enough to use for this.
 126                 */
 127
 128                 while (cpath[n] && mntbufp[i].f_mntonname[n]) {
 129                         if (cpath[n] != mntbufp[i].f_mntonname[n]) {
 130                                 break;
 131                         }
 132                         matchlen++;
 133                         n++;
 134                 }
 135
 136                 if (cpath[matchlen] == '\0') {
 137                         snprintf(best, sizeof(best), "%s", mntbufp[i].f_mntonname);
 138                         free(mntbufp);
 139                         return best;
 140
 141                 } else {
 142
 143                         if (matchlen > maxmatch) {
 144                                 snprintf (best, sizeof(best), "%s", mntbufp[i].f_mntonname);
 145                                 maxmatch = matchlen;
 146                         }
 147                 }
 148         }
 149
 150         free(mntbufp);
 151
 152         return best;
 153 }
 154 #endif // HAVE_GETMNTENT
 155
 156 #ifdef TEST_MOUNTPOINT
 157
 158 main (int argc, char *argv[])
 159 {
 160         printf ("mp of %s = %s\n", argv[1], mountpoint (argv[1]).c_str());
 161         exit (0);
 162 }
 163
 164 #endif // TEST_MOUNTPOINT