diff options
Diffstat (limited to 'subversion/libsvn_fs_base/bdb/changes-table.c')
| -rw-r--r-- | subversion/libsvn_fs_base/bdb/changes-table.c | 457 |
1 files changed, 457 insertions, 0 deletions
diff --git a/subversion/libsvn_fs_base/bdb/changes-table.c b/subversion/libsvn_fs_base/bdb/changes-table.c new file mode 100644 index 0000000..80ff468 --- /dev/null +++ b/subversion/libsvn_fs_base/bdb/changes-table.c @@ -0,0 +1,457 @@ +/* changes-table.c : operations on the `changes' table + * + * ==================================================================== + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + * ==================================================================== + */ + +#include "bdb_compat.h" + +#include <apr_hash.h> +#include <apr_tables.h> + +#include "svn_hash.h" +#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 "private/svn_fs_util.h" +#include "private/svn_fspath.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; + svn_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"); + return BDB_WRAP(fs, N_("creating change"), + bfd->changes->put(bfd->changes, trail->db_txn, + &query, &value, 0)); +} + + +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 propagated to the caller, though. */ + if ((db_err) && (db_err != DB_NOTFOUND)) + { + SVN_ERR(BDB_WRAP(fs, N_("deleting changes"), db_err)); + } + + return SVN_NO_ERROR; +} + + +/* Merge the internal-use-only CHANGE into a hash of public-FS + svn_fs_path_change2_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_change2_t *old_change, *new_change; + const char *path; + + if ((old_change = svn_hash_gets(changes, change->path))) + { + /* 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")); + + /* Sanity check: an add can't follow anything except + a delete or reset. */ + if ((change->kind == svn_fs_path_change_add) + && (old_change->change_kind != svn_fs_path_change_delete) + && (old_change->change_kind != svn_fs_path_change_reset)) + return svn_error_create + (SVN_ERR_FS_CORRUPT, NULL, + _("Invalid change ordering: add change on preexisting 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 = svn_fs__path_change_create_internal( + svn_fs_base__id_copy(change->noderev_id, pool), + change->kind, + pool); + new_change->text_mod = change->text_mod; + new_change->prop_mod = change->prop_mod; + new_change->node_kind = svn_node_unknown; + new_change->copyfrom_known = FALSE; + path = apr_pstrdup(pool, change->path); + } + + /* Add (or update) this path. */ + svn_hash_sets(changes, path, 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, N_("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 = svn_bdb_dbc_get(cursor, &query, &result, DB_SET); + if (! db_err) + svn_fs_base__track_dbt(&result, pool); + + while (! db_err) + { + change_t *change; + svn_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_skel__parse(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; + const char *child_relpath; + + apr_hash_this(hi, &hashkey, &klen, NULL); + + /* If we come across our own path, ignore it. + If we come across a child of our path, remove it. */ + child_relpath = svn_fspath__skip_ancestor(change->path, hashkey); + if (child_relpath && *child_relpath) + 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 = svn_bdb_dbc_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, N_("fetching changes"), db_err); + + cleanup: + /* Close the cursor. */ + db_c_err = svn_bdb_dbc_close(cursor); + + /* If we had an error prior to closing the cursor, return the error. */ + if (err) + return svn_error_trace(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, N_("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, N_("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 = svn_bdb_dbc_get(cursor, &query, &result, DB_SET); + if (! db_err) + svn_fs_base__track_dbt(&result, pool); + + while (! db_err) + { + svn_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_skel__parse(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. */ + APR_ARRAY_PUSH(changes, change_t *) = change; + + /* Advance the cursor to the next record with this same KEY, and + fetch that record. */ + svn_fs_base__result_dbt(&result); + db_err = svn_bdb_dbc_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, N_("fetching changes"), db_err); + + cleanup: + /* Close the cursor. */ + db_c_err = svn_bdb_dbc_close(cursor); + + /* If we had an error prior to closing the cursor, return the error. */ + if (err) + return svn_error_trace(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, N_("closing changes cursor"), db_c_err)); + + /* Finally, set our return variable and get outta here. */ + *changes_p = changes; + return SVN_NO_ERROR; +} |
