/* changes-table.c : operations on the `changes' table * * ==================================================================== * Copyright (c) 2000-2004 CollabNet. All rights reserved. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at http://subversion.tigris.org/license-1.html. * If newer versions of this license are posted there, you may use a * newer version instead, at your option. * * This software consists of voluntary contributions made by many * individuals. For exact contribution history, see the revision * history and logs, available at http://subversion.tigris.org/. * ==================================================================== */ #include "bdb_compat.h" #include #include #include "svn_fs.h" #include "svn_pools.h" #include "svn_path.h" #include "../fs.h" #include "../err.h" #include "../trail.h" #include "../id.h" #include "../util/fs_skels.h" #include "../../libsvn_fs/fs-loader.h" #include "bdb-err.h" #include "dbt.h" #include "changes-table.h" #include "svn_private_config.h" /*** Creating and opening the changes table. ***/ int svn_fs_bdb__open_changes_table(DB **changes_p, DB_ENV *env, svn_boolean_t create) { const u_int32_t open_flags = (create ? (DB_CREATE | DB_EXCL) : 0); DB *changes; BDB_ERR(svn_fs_bdb__check_version()); BDB_ERR(db_create(&changes, env, 0)); /* Enable duplicate keys. This allows us to store the changes one-per-row. Note: this must occur before ->open(). */ BDB_ERR(changes->set_flags(changes, DB_DUP)); BDB_ERR(changes->open(SVN_BDB_OPEN_PARAMS(changes, NULL), "changes", 0, DB_BTREE, open_flags, 0666)); *changes_p = changes; return 0; } /*** Storing and retrieving changes. ***/ svn_error_t * svn_fs_bdb__changes_add(svn_fs_t *fs, const char *key, change_t *change, trail_t *trail, apr_pool_t *pool) { base_fs_data_t *bfd = fs->fsap_data; DBT query, value; skel_t *skel; /* Convert native type to skel. */ SVN_ERR(svn_fs_base__unparse_change_skel(&skel, change, pool)); /* Store a new record into the database. */ svn_fs_base__str_to_dbt(&query, key); svn_fs_base__skel_to_dbt(&value, skel, pool); svn_fs_base__trail_debug(trail, "changes", "put"); SVN_ERR(BDB_WRAP(fs, _("creating change"), bfd->changes->put(bfd->changes, trail->db_txn, &query, &value, 0))); return SVN_NO_ERROR; } svn_error_t * svn_fs_bdb__changes_delete(svn_fs_t *fs, const char *key, trail_t *trail, apr_pool_t *pool) { int db_err; DBT query; base_fs_data_t *bfd = fs->fsap_data; svn_fs_base__trail_debug(trail, "changes", "del"); db_err = bfd->changes->del(bfd->changes, trail->db_txn, svn_fs_base__str_to_dbt(&query, key), 0); /* If there're no changes for KEY, that is acceptable. Any other error should be propogated to the caller, though. */ if ((db_err) && (db_err != DB_NOTFOUND)) { SVN_ERR(BDB_WRAP(fs, _("deleting changes"), db_err)); } return SVN_NO_ERROR; } /* Merge the internal-use-only CHANGE into a hash of public-FS svn_fs_path_change_t CHANGES, collapsing multiple changes into a single succinct change per path. */ static svn_error_t * fold_change(apr_hash_t *changes, const change_t *change) { apr_pool_t *pool = apr_hash_pool_get(changes); svn_fs_path_change_t *old_change, *new_change; const char *path; if ((old_change = apr_hash_get(changes, change->path, APR_HASH_KEY_STRING))) { /* This path already exists in the hash, so we have to merge this change into the already existing one. */ /* Since the path already exists in the hash, we don't have to dup the allocation for the path itself. */ path = change->path; /* Sanity check: only allow NULL node revision ID in the `reset' case. */ if ((! change->noderev_id) && (change->kind != svn_fs_path_change_reset)) return svn_error_create (SVN_ERR_FS_CORRUPT, NULL, _("Missing required node revision ID")); /* Sanity check: we should be talking about the same node revision ID as our last change except where the last change was a deletion. */ if (change->noderev_id && (! svn_fs_base__id_eq(old_change->node_rev_id, change->noderev_id)) && (old_change->change_kind != svn_fs_path_change_delete)) return svn_error_create (SVN_ERR_FS_CORRUPT, NULL, _("Invalid change ordering: new node revision ID without delete")); /* Sanity check: an add, replacement, or reset must be the first thing to follow a deletion. */ if ((old_change->change_kind == svn_fs_path_change_delete) && (! ((change->kind == svn_fs_path_change_replace) || (change->kind == svn_fs_path_change_reset) || (change->kind == svn_fs_path_change_add)))) return svn_error_create (SVN_ERR_FS_CORRUPT, NULL, _("Invalid change ordering: non-add change on deleted path")); /* Now, merge that change in. */ switch (change->kind) { case svn_fs_path_change_reset: /* A reset here will simply remove the path change from the hash. */ old_change = NULL; break; case svn_fs_path_change_delete: if (old_change->change_kind == svn_fs_path_change_add) { /* If the path was introduced in this transaction via an add, and we are deleting it, just remove the path altogether. */ old_change = NULL; } else { /* A deletion overrules all previous changes. */ old_change->change_kind = svn_fs_path_change_delete; old_change->text_mod = change->text_mod; old_change->prop_mod = change->prop_mod; } break; case svn_fs_path_change_add: case svn_fs_path_change_replace: /* An add at this point must be following a previous delete, so treat it just like a replace. */ old_change->change_kind = svn_fs_path_change_replace; old_change->node_rev_id = svn_fs_base__id_copy(change->noderev_id, pool); old_change->text_mod = change->text_mod; old_change->prop_mod = change->prop_mod; break; case svn_fs_path_change_modify: default: if (change->text_mod) old_change->text_mod = TRUE; if (change->prop_mod) old_change->prop_mod = TRUE; break; } /* Point our new_change to our (possibly modified) old_change. */ new_change = old_change; } else { /* This change is new to the hash, so make a new public change structure from the internal one (in the hash's pool), and dup the path into the hash's pool, too. */ new_change = apr_pcalloc(pool, sizeof(*new_change)); new_change->node_rev_id = svn_fs_base__id_copy(change->noderev_id, pool); new_change->change_kind = change->kind; new_change->text_mod = change->text_mod; new_change->prop_mod = change->prop_mod; path = apr_pstrdup(pool, change->path); } /* Add (or update) this path. */ apr_hash_set(changes, path, APR_HASH_KEY_STRING, new_change); return SVN_NO_ERROR; } svn_error_t * svn_fs_bdb__changes_fetch(apr_hash_t **changes_p, svn_fs_t *fs, const char *key, trail_t *trail, apr_pool_t *pool) { base_fs_data_t *bfd = fs->fsap_data; DBC *cursor; DBT query, result; int db_err = 0, db_c_err = 0; svn_error_t *err = SVN_NO_ERROR; apr_hash_t *changes = apr_hash_make(pool); apr_pool_t *subpool = svn_pool_create(pool); /* Get a cursor on the first record matching KEY, and then loop over the records, adding them to the return array. */ svn_fs_base__trail_debug(trail, "changes", "cursor"); SVN_ERR(BDB_WRAP(fs, _("creating cursor for reading changes"), bfd->changes->cursor(bfd->changes, trail->db_txn, &cursor, 0))); /* Advance the cursor to the key that we're looking for. */ svn_fs_base__str_to_dbt(&query, key); svn_fs_base__result_dbt(&result); db_err = cursor->c_get(cursor, &query, &result, DB_SET); if (! db_err) svn_fs_base__track_dbt(&result, pool); while (! db_err) { change_t *change; skel_t *result_skel; /* Clear the per-iteration subpool. */ svn_pool_clear(subpool); /* RESULT now contains a change record associated with KEY. We need to parse that skel into an change_t structure ... */ result_skel = svn_fs_base__parse_skel(result.data, result.size, subpool); if (! result_skel) { err = svn_error_createf(SVN_ERR_FS_CORRUPT, NULL, _("Error reading changes for key '%s'"), key); goto cleanup; } err = svn_fs_base__parse_change_skel(&change, result_skel, subpool); if (err) goto cleanup; /* ... and merge it with our return hash. */ err = fold_change(changes, change); if (err) goto cleanup; /* Now, if our change was a deletion or replacement, we have to blow away any changes thus far on paths that are (or, were) children of this path. ### i won't bother with another iteration pool here -- at most we talking about a few extra dups of paths into what is already a temporary subpool. */ if ((change->kind == svn_fs_path_change_delete) || (change->kind == svn_fs_path_change_replace)) { apr_hash_index_t *hi; for (hi = apr_hash_first(subpool, changes); hi; hi = apr_hash_next(hi)) { /* KEY is the path. */ const void *hashkey; apr_ssize_t klen; apr_hash_this(hi, &hashkey, &klen, NULL); /* If we come across our own path, ignore it. */ if (strcmp(change->path, hashkey) == 0) continue; /* If we come across a child of our path, remove it. */ if (svn_path_is_child(change->path, hashkey, subpool)) apr_hash_set(changes, hashkey, klen, NULL); } } /* Advance the cursor to the next record with this same KEY, and fetch that record. */ svn_fs_base__result_dbt(&result); db_err = cursor->c_get(cursor, &query, &result, DB_NEXT_DUP); if (! db_err) svn_fs_base__track_dbt(&result, pool); } /* Destroy the per-iteration subpool. */ svn_pool_destroy(subpool); /* If there are no (more) change records for this KEY, we're finished. Just return the (possibly empty) array. Any other error, however, needs to get handled appropriately. */ if (db_err && (db_err != DB_NOTFOUND)) err = BDB_WRAP(fs, _("fetching changes"), db_err); cleanup: /* Close the cursor. */ db_c_err = cursor->c_close(cursor); /* If we had an error prior to closing the cursor, return the error. */ if (err) return err; /* If our only error thus far was when we closed the cursor, return that error. */ if (db_c_err) SVN_ERR(BDB_WRAP(fs, _("closing changes cursor"), db_c_err)); /* Finally, set our return variable and get outta here. */ *changes_p = changes; return SVN_NO_ERROR; } svn_error_t * svn_fs_bdb__changes_fetch_raw(apr_array_header_t **changes_p, svn_fs_t *fs, const char *key, trail_t *trail, apr_pool_t *pool) { base_fs_data_t *bfd = fs->fsap_data; DBC *cursor; DBT query, result; int db_err = 0, db_c_err = 0; svn_error_t *err = SVN_NO_ERROR; change_t *change; apr_array_header_t *changes = apr_array_make(pool, 4, sizeof(change)); /* Get a cursor on the first record matching KEY, and then loop over the records, adding them to the return array. */ svn_fs_base__trail_debug(trail, "changes", "cursor"); SVN_ERR(BDB_WRAP(fs, _("creating cursor for reading changes"), bfd->changes->cursor(bfd->changes, trail->db_txn, &cursor, 0))); /* Advance the cursor to the key that we're looking for. */ svn_fs_base__str_to_dbt(&query, key); svn_fs_base__result_dbt(&result); db_err = cursor->c_get(cursor, &query, &result, DB_SET); if (! db_err) svn_fs_base__track_dbt(&result, pool); while (! db_err) { skel_t *result_skel; /* RESULT now contains a change record associated with KEY. We need to parse that skel into an change_t structure ... */ result_skel = svn_fs_base__parse_skel(result.data, result.size, pool); if (! result_skel) { err = svn_error_createf(SVN_ERR_FS_CORRUPT, NULL, _("Error reading changes for key '%s'"), key); goto cleanup; } err = svn_fs_base__parse_change_skel(&change, result_skel, pool); if (err) goto cleanup; /* ... and add it to our return array. */ (*((change_t **) apr_array_push(changes))) = change; /* Advance the cursor to the next record with this same KEY, and fetch that record. */ svn_fs_base__result_dbt(&result); db_err = cursor->c_get(cursor, &query, &result, DB_NEXT_DUP); if (! db_err) svn_fs_base__track_dbt(&result, pool); } /* If there are no (more) change records for this KEY, we're finished. Just return the (possibly empty) array. Any other error, however, needs to get handled appropriately. */ if (db_err && (db_err != DB_NOTFOUND)) err = BDB_WRAP(fs, _("fetching changes"), db_err); cleanup: /* Close the cursor. */ db_c_err = cursor->c_close(cursor); /* If we had an error prior to closing the cursor, return the error. */ if (err) return err; /* If our only error thus far was when we closed the cursor, return that error. */ if (db_c_err) SVN_ERR(BDB_WRAP(fs, _("closing changes cursor"), db_c_err)); /* Finally, set our return variable and get outta here. */ *changes_p = changes; return SVN_NO_ERROR; }