lib/libhammer/info.c

   1 /*
   2  * Copyright (c) 2011 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Antonio Huete <tuxillo@quantumachine.net>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <dirent.h>
  36 #include <err.h>
  37 #include <errno.h>
  38 #include <fcntl.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <sys/param.h>
  43 #include <sys/stat.h>
  44 #include <unistd.h>
  45
  46 #include "libhammer.h"
  47
  48 static u_int32_t count_snapshots(u_int32_t, char *, char *, int *);
  49
  50 libhammer_volinfo_t
  51 libhammer_get_volinfo(const char *path)
  52 {
  53         struct hammer_pseudofs_data *pfs_od;
  54         struct hammer_ioc_pfs_iterate pi;
  55         struct hammer_ioc_info info;
  56         libhammer_pfsinfo_t pfstmp;
  57         libhammer_volinfo_t hvi;
  58         int error = 0;
  59         int fd;
  60
  61         if ((fd = open(path, O_RDONLY)) < 0)
  62                 return NULL;
  63
  64         hvi = _libhammer_malloc(sizeof(*hvi));
  65         TAILQ_INIT(&hvi->list_pseudo);
  66         if ((ioctl(fd, HAMMERIOC_GET_INFO, &info)) < 0) {
  67                 libhammer_free_volinfo(hvi);
  68                 close(fd);
  69                 return NULL;
  70         }
  71
  72         /* Fill volume information */
  73         snprintf(hvi->vol_name, TXTLEN, "%s", info.vol_name);
  74         hvi->vol_fsid = info.vol_fsid;
  75         hvi->version = info.version;
  76         hvi->nvolumes = info.nvolumes;
  77         hvi->inodes = info.inodes;
  78         hvi->bigblocks = info.bigblocks;
  79         hvi->freebigblocks = info.freebigblocks;
  80         hvi->rsvbigblocks = info.rsvbigblocks;
  81
  82         bzero(&pi, sizeof(pi));
  83         pi.ondisk = _libhammer_malloc(sizeof(*pfs_od));
  84         while(error == 0) {
  85                 error = ioctl(fd, HAMMERIOC_PFS_ITERATE, &pi);
  86                 if (error == 0 &&
  87                     ((pi.head.flags & HAMMER_PFSD_DELETED) == 0)) {
  88                         /*
  89                          * XXX - In the case the path passed is on PFS#0 but it
  90                          * is not the mountpoint itself, it could produce a
  91                          * wrong type of PFS.
  92                          */
  93                         pfstmp = _libhammer_malloc(sizeof(*pfstmp));
  94                         pfs_od = pi.ondisk;
  95                         pfstmp->ismaster =
  96                             (pfs_od->mirror_flags & HAMMER_PFSD_SLAVE) ? 0 : 1;
  97
  98                         if (pi.pos == 0)
  99                                 pfstmp->mountedon = strdup(path);
 100                         else
 101                                 pfstmp->mountedon =
 102                                     libhammer_find_pfs_mount(pi.pos,
 103                                         hvi->vol_fsid, pfstmp->ismaster);
 104                         /*
 105                          * Fill in structs used in the library. We don't rely on
 106                          * HAMMER own struct but we do fill our own.
 107                          */
 108                         pfstmp->version = hvi->version;
 109                         pfstmp->pfs_id = pi.pos;
 110                         pfstmp->mirror_flags = pfs_od->mirror_flags;
 111                         pfstmp->beg_tid = pfs_od->sync_beg_tid;
 112                         pfstmp->end_tid = pfs_od->sync_end_tid;
 113                         pfstmp->snapcount = count_snapshots(hvi->version,
 114                             pfstmp->snapshots, pfstmp->mountedon,
 115                             &pfstmp->head.error);
 116
 117                         TAILQ_INSERT_TAIL(&hvi->list_pseudo, pfstmp, entries);
 118                 }
 119                 pi.pos++;
 120         }
 121         free(pi.ondisk);
 122
 123         close (fd);
 124
 125         return (hvi);
 126 }
 127
 128 void
 129 libhammer_free_volinfo(libhammer_volinfo_t volinfo)
 130 {
 131         struct libhammer_pfsinfo *pfstmp;
 132
 133         while(!TAILQ_EMPTY(&volinfo->list_pseudo)) {
 134                 pfstmp = TAILQ_FIRST(&volinfo->list_pseudo);
 135                 free(pfstmp->mountedon);
 136                 TAILQ_REMOVE(&volinfo->list_pseudo, pfstmp, entries);
 137                 free(pfstmp);
 138         }
 139         free(volinfo);
 140 }
 141
 142 static u_int32_t
 143 count_snapshots(u_int32_t version, char *pfs_snapshots, char *mountedon,
 144     int *errorp)
 145 {
 146         struct hammer_ioc_snapshot snapinfo;
 147         char *snapshots_path, *fpath;
 148         struct dirent *den;
 149         struct stat st;
 150         DIR *dir;
 151         u_int32_t snapshot_count;
 152         int fd;
 153         int spallocated;
 154
 155         snapshot_count = 0;
 156
 157         bzero(&snapinfo, sizeof(struct hammer_ioc_snapshot));
 158
 159         fd = open(mountedon, O_RDONLY);
 160         if (fd < 0) {
 161                 *errorp = errno;
 162                 return 0;
 163         }
 164
 165         if (version < 3) {
 166                 /*
 167                  * old style: count the number of softlinks in the snapshots dir
 168                  */
 169                 if (pfs_snapshots[0]) {
 170                         snapshots_path = pfs_snapshots;
 171                         spallocated = 0;
 172                 } else {
 173                         asprintf(&snapshots_path, "%s/snapshots", mountedon);
 174                         spallocated = 1;
 175                 }
 176                 if ((dir = opendir(snapshots_path)) != NULL) {
 177                         while ((den = readdir(dir)) != NULL) {
 178                                 if (den->d_name[0] == '.')
 179                                         continue;
 180                                 asprintf(&fpath, "%s/%s", snapshots_path,
 181                                     den->d_name);
 182                                 if (lstat(fpath, &st) == 0 &&
 183                                     S_ISLNK(st.st_mode))
 184                                         snapshot_count++;
 185                                 free(fpath);
 186                         }
 187                         closedir(dir);
 188                 }
 189                 if (spallocated)
 190                         free(snapshots_path);
 191         } else {
 192                 /*
 193                  * new style: file system meta-data
 194                  */
 195                 do {
 196                         if (ioctl(fd, HAMMERIOC_GET_SNAPSHOT, &snapinfo) < 0) {
 197                                 *errorp = errno;
 198                                 goto out;
 199                         }
 200
 201                         snapshot_count += snapinfo.count;
 202                 } while (snapinfo.head.error == 0 && snapinfo.count);
 203         }
 204
 205 out:
 206         if (fd != -1)
 207                 close(fd);
 208         return snapshot_count;
 209 }