lib/dpkg/db-ctrl-upgrade.c

   1 /*
   2  * libdpkg - Debian packaging suite library routines
   3  * db-ctrl-upgrade.c - package control information database format upgrade
   4  *
   5  * Copyright © 1995 Ian Jackson <ijackson@chiark.greenend.org.uk>
   6  * Copyright © 2011-2014 Guillem Jover <guillem@debian.org>
   7  * Copyright © 2011 Linaro Limited
   8  * Copyright © 2011 Raphaël Hertzog <hertzog@debian.org>
   9  *
  10  * This is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  22  */
  23
  24 #include <config.h>
  25 #include <compat.h>
  26
  27 #include <sys/types.h>
  28 #include <sys/stat.h>
  29
  30 #include <errno.h>
  31 #include <stdlib.h>
  32 #include <unistd.h>
  33
  34 #include <dpkg/i18n.h>
  35 #include <dpkg/dpkg.h>
  36 #include <dpkg/dpkg-db.h>
  37 #include <dpkg/fsys.h>
  38 #include <dpkg/db-ctrl.h>
  39 #include <dpkg/path.h>
  40 #include <dpkg/dir.h>
  41
  42 struct rename_node {
  43         struct rename_node *next;
  44         char *old;
  45         char *new;
  46 };
  47
  48 /* Global variables. */
  49 static struct rename_node *rename_head = NULL;
  50
  51 static struct rename_node *
  52 rename_node_new(const char *old, const char *new, struct rename_node *next)
  53 {
  54         struct rename_node *node;
  55
  56         node = m_malloc(sizeof(*node));
  57         node->next = next;
  58         node->old = m_strdup(old);
  59         node->new = m_strdup(new);
  60
  61         return node;
  62 }
  63
  64 static void
  65 rename_node_free(struct rename_node *node)
  66 {
  67         free(node->old);
  68         free(node->new);
  69         free(node);
  70 }
  71
  72 static void
  73 pkg_infodb_link_multiarch_files(void)
  74 {
  75         DIR *db_dir;
  76         struct dirent *db_de;
  77         struct varbuf pkgname = VARBUF_INIT;
  78         struct varbuf oldname = VARBUF_INIT;
  79         struct varbuf newname = VARBUF_INIT;
  80         struct varbuf_state oldname_state;
  81         struct varbuf_state newname_state;
  82
  83         varbuf_add_dir(&oldname, pkg_infodb_get_dir());
  84         varbuf_snapshot(&oldname, &oldname_state);
  85
  86         varbuf_set_varbuf(&newname, &oldname);
  87         varbuf_snapshot(&newname, &newname_state);
  88
  89         db_dir = opendir(pkg_infodb_get_dir());
  90         if (!db_dir)
  91                 ohshite(_("cannot read info directory"));
  92
  93         push_cleanup(cu_closedir, ~0, 1, (void *)db_dir);
  94         while ((db_de = readdir(db_dir)) != NULL) {
  95                 const char *filetype, *dot;
  96                 struct pkginfo *pkg;
  97                 struct pkgset *set;
  98
  99                 /* Ignore dotfiles, including ‘.’ and ‘..’. */
 100                 if (db_de->d_name[0] == '.')
 101                         continue;
 102
 103                 /* Ignore anything odd. */
 104                 dot = strrchr(db_de->d_name, '.');
 105                 if (dot == NULL)
 106                         continue;
 107
 108                 varbuf_set_buf(&pkgname, db_de->d_name, dot - db_de->d_name);
 109
 110                  /* Skip files already converted. */
 111                 if (strchr(pkgname.buf, ':'))
 112                         continue;
 113
 114                 set = pkg_hash_find_set(pkgname.buf);
 115                 for (pkg = &set->pkg; pkg; pkg = pkg->arch_next)
 116                         if (pkg->status != PKG_STAT_NOTINSTALLED)
 117                                 break;
 118                 if (!pkg) {
 119                         warning(_("info file %s/%s not associated to any package"),
 120                                 pkg_infodb_get_dir(), db_de->d_name);
 121                         continue;
 122                 }
 123
 124                 /* Does it need to be upgraded? */
 125                 if (pkg->installed.multiarch != PKG_MULTIARCH_SAME)
 126                         continue;
 127
 128                 /* Skip past the full stop. */
 129                 filetype = dot + 1;
 130
 131                 varbuf_rollback(&oldname_state);
 132                 varbuf_add_str(&oldname, db_de->d_name);
 133
 134                 varbuf_rollback(&newname_state);
 135                 varbuf_add_pkgbin_name(&newname, pkg, &pkg->installed, pnaw_always);
 136                 varbuf_add_char(&newname, '.');
 137                 varbuf_add_str(&newname, filetype);
 138
 139                 if (link(oldname.buf, newname.buf) && errno != EEXIST)
 140                         ohshite(_("error creating hard link '%.255s'"),
 141                                 newname.buf);
 142                 rename_head = rename_node_new(oldname.buf, newname.buf, rename_head);
 143         }
 144         pop_cleanup(ehflag_normaltidy); /* closedir */
 145
 146         varbuf_destroy(&pkgname);
 147         varbuf_destroy(&newname);
 148         varbuf_destroy(&oldname);
 149 }
 150
 151 static void
 152 cu_abort_db_upgrade(int argc, void **argv)
 153 {
 154         struct atomic_file *file = argv[0];
 155         struct rename_node *next;
 156
 157         /* Restore the old files if needed and drop the newly created files. */
 158         while (rename_head) {
 159                 next = rename_head->next;
 160                 if (link(rename_head->new, rename_head->old) && errno != EEXIST)
 161                         ohshite(_("error creating hard link '%.255s'"),
 162                                 rename_head->old);
 163                 if (unlink(rename_head->new))
 164                         ohshite(_("cannot remove '%.250s'"), rename_head->new);
 165                 rename_node_free(rename_head);
 166                 rename_head = next;
 167         }
 168         if (unlink(file->name_new) && errno != ENOENT)
 169                 ohshite(_("cannot remove '%.250s'"), file->name_new);
 170
 171         atomic_file_free(file);
 172 }
 173
 174 static void
 175 pkg_infodb_write_format(struct atomic_file *file, int version)
 176 {
 177         if (fprintf(file->fp, "%d\n", version) < 0)
 178                 ohshite(_("error while writing '%s'"), file->name_new);
 179
 180         atomic_file_sync(file);
 181         atomic_file_close(file);
 182         dir_sync_path_parent(file->name);
 183
 184         pkg_infodb_set_format(version);
 185 }
 186
 187 static void
 188 pkg_infodb_unlink_monoarch_files(void)
 189 {
 190         struct rename_node *next;
 191
 192         while (rename_head) {
 193                 next = rename_head->next;
 194                 if (unlink(rename_head->old))
 195                         ohshite(_("cannot remove '%.250s'"), rename_head->old);
 196                 rename_node_free(rename_head);
 197                 rename_head = next;
 198         }
 199 }
 200
 201 static void
 202 pkg_infodb_upgrade_to_multiarch(void)
 203 {
 204         struct atomic_file *db_file;
 205         char *db_format_file;
 206
 207         db_format_file = dpkg_db_get_path(INFODIR "/format");
 208         db_file = atomic_file_new(db_format_file, ATOMIC_FILE_MKPATH);
 209         atomic_file_open(db_file);
 210
 211         push_cleanup(cu_abort_db_upgrade, ehflag_bombout, 1, db_file);
 212
 213         pkg_infodb_link_multiarch_files();
 214         pkg_infodb_write_format(db_file, 1);
 215
 216         pkg_infodb_unlink_monoarch_files();
 217         atomic_file_commit(db_file);
 218         dir_sync_path(pkg_infodb_get_dir());
 219
 220         pop_cleanup(ehflag_normaltidy);
 221
 222         atomic_file_free(db_file);
 223         free(db_format_file);
 224 }
 225
 226 /**
 227  * Upgrade the infodb if there's the need and possibility.
 228  *
 229  * Currently this implies, that the modstatdb was opened for writing and:
 230  * - previous upgrade has not been completed; or
 231  * - current format is not the latest one.
 232  */
 233 void
 234 pkg_infodb_upgrade(void)
 235 {
 236         enum pkg_infodb_format db_format;
 237
 238         /* Make sure to always read and verify the format version. */
 239         db_format = pkg_infodb_get_format();
 240
 241         if (modstatdb_get_status() < msdbrw_write)
 242                 return;
 243
 244         if (db_format < PKG_INFODB_FORMAT_MULTIARCH ||
 245             pkg_infodb_is_upgrading())
 246                 pkg_infodb_upgrade_to_multiarch();
 247 }