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Diffstat (limited to 'subversion/libsvn_fs_fs/low_level.h')
| -rw-r--r-- | subversion/libsvn_fs_fs/low_level.h | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/subversion/libsvn_fs_fs/low_level.h b/subversion/libsvn_fs_fs/low_level.h new file mode 100644 index 0000000..35b9d0d --- /dev/null +++ b/subversion/libsvn_fs_fs/low_level.h @@ -0,0 +1,230 @@ +/* low_level.c --- low level r/w access to fs_fs file structures + * + * ==================================================================== + * 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 "svn_fs.h" + +#include "fs_fs.h" +#include "id.h" + +/* Kinds that a node-rev can be. */ +#define SVN_FS_FS__KIND_FILE "file" +#define SVN_FS_FS__KIND_DIR "dir" + +/* The functions are grouped as follows: + * + * - revision trailer (up to format 6) + * - revision footer (since format 7) + * - changed path list + * - node revision + * - representation (as in "text:" and "props:" lines) + * - representation header ("PLAIN" and "DELTA" lines) + */ + +/* Given the last "few" bytes (should be at least 40) of revision REV in + * TRAILER, parse the last line and return the offset of the root noderev + * in *ROOT_OFFSET and the offset of the changed paths list in + * *CHANGES_OFFSET. Offsets are relative to the revision's start offset. + * ROOT_OFFSET and / or CHANGES_OFFSET may be NULL. + * + * Note that REV is only used to construct nicer error objects. + */ +svn_error_t * +svn_fs_fs__parse_revision_trailer(apr_off_t *root_offset, + apr_off_t *changes_offset, + svn_stringbuf_t *trailer, + svn_revnum_t rev); + +/* Given the offset of the root noderev in ROOT_OFFSET and the offset of + * the changed paths list in CHANGES_OFFSET, return the corresponding + * revision's trailer. Allocate it in RESULT_POOL. + */ +svn_stringbuf_t * +svn_fs_fs__unparse_revision_trailer(apr_off_t root_offset, + apr_off_t changes_offset, + apr_pool_t *result_pool); + +/* Given the format 7+ revision / pack FOOTER, parse it destructively + * and return the start offsets of the index data in *L2P_OFFSET and + * *P2L_OFFSET, respectively. Also, return the expected checksums in + * in *L2P_CHECKSUM and *P2L_CHECKSUM. + * + * Note that REV is only used to construct nicer error objects that + * mention this revision. Allocate the checksums in RESULT_POOL. + */ +svn_error_t * +svn_fs_fs__parse_footer(apr_off_t *l2p_offset, + svn_checksum_t **l2p_checksum, + apr_off_t *p2l_offset, + svn_checksum_t **p2l_checksum, + svn_stringbuf_t *footer, + svn_revnum_t rev, + apr_pool_t *result_pool); + +/* Given the offset of the L2P index data in L2P_OFFSET, the content + * checksum in L2P_CHECKSUM and the offset plus checksum of the P2L + * index data in P2L_OFFSET and P2L_CHECKSUM. + * + * Return the corresponding format 7+ revision / pack file footer. + * Allocate it in RESULT_POOL and use SCRATCH_POOL for temporary. + */ +svn_stringbuf_t * +svn_fs_fs__unparse_footer(apr_off_t l2p_offset, + svn_checksum_t *l2p_checksum, + apr_off_t p2l_offset, + svn_checksum_t *p2l_checksum, + apr_pool_t *result_pool, + apr_pool_t *scratch_pool); + +/* Read all the changes from STREAM and store them in *CHANGES, + allocated in RESULT_POOL. Do temporary allocations in SCRATCH_POOL. */ +svn_error_t * +svn_fs_fs__read_changes(apr_array_header_t **changes, + svn_stream_t *stream, + apr_pool_t *result_pool, + apr_pool_t *scratch_pool); + +/* Callback function used by svn_fs_fs__read_changes_incrementally(), + * asking the receiver to process to process CHANGE using BATON. CHANGE + * and SCRATCH_POOL will not be valid beyond the current callback invocation. + */ +typedef svn_error_t *(*svn_fs_fs__change_receiver_t)( + void *baton, + change_t *change, + apr_pool_t *scratch_pool); + +/* Read all the changes from STREAM and invoke CHANGE_RECEIVER on each change. + Do all allocations in SCRATCH_POOL. */ +svn_error_t * +svn_fs_fs__read_changes_incrementally(svn_stream_t *stream, + svn_fs_fs__change_receiver_t + change_receiver, + void *change_receiver_baton, + apr_pool_t *scratch_pool); + +/* Write the changed path info from CHANGES in filesystem FS to the + output stream STREAM. You may call this function multiple time on + the same stream. If you are writing to a (proto-)revision file, + the last call must set TERMINATE_LIST to write an extra empty line + that marks the end of the changed paths list. + Perform temporary allocations in SCRATCH_POOL. + */ +svn_error_t * +svn_fs_fs__write_changes(svn_stream_t *stream, + svn_fs_t *fs, + apr_hash_t *changes, + svn_boolean_t terminate_list, + apr_pool_t *scratch_pool); + +/* Read a node-revision from STREAM. Set *NODEREV to the new structure, + allocated in RESULT_POOL. */ +svn_error_t * +svn_fs_fs__read_noderev(node_revision_t **noderev, + svn_stream_t *stream, + apr_pool_t *result_pool, + apr_pool_t *scratch_pool); + +/* Write the node-revision NODEREV into the stream OUTFILE, compatible with + filesystem format FORMAT. Only write mergeinfo-related metadata if + INCLUDE_MERGEINFO is true. Temporary allocations are from SCRATCH_POOL. */ +svn_error_t * +svn_fs_fs__write_noderev(svn_stream_t *outfile, + node_revision_t *noderev, + int format, + svn_boolean_t include_mergeinfo, + apr_pool_t *scratch_pool); + +/* Parse the description of a representation from TEXT and store it + into *REP_P. TEXT will be invalidated by this call. Allocate *REP_P in + RESULT_POOL and use SCRATCH_POOL for temporaries. */ +svn_error_t * +svn_fs_fs__parse_representation(representation_t **rep_p, + svn_stringbuf_t *text, + apr_pool_t *result_pool, + apr_pool_t *scratch_pool); + +/* Return a formatted string, compatible with filesystem format FORMAT, + that represents the location of representation REP. If + MUTABLE_REP_TRUNCATED is given, the rep is for props or dir contents, + and only a "-1" revision number will be given for a mutable rep. + If MAY_BE_CORRUPT is true, guard for NULL when constructing the string. + Allocate the result in RESULT_POOL and temporaries in SCRATCH_POOL. */ +svn_stringbuf_t * +svn_fs_fs__unparse_representation(representation_t *rep, + int format, + svn_boolean_t mutable_rep_truncated, + apr_pool_t *result_pool, + apr_pool_t *scratch_pool); + +/* This type enumerates all forms of representations that we support. */ +typedef enum svn_fs_fs__rep_type_t +{ + /* this is a PLAIN representation */ + svn_fs_fs__rep_plain, + + /* this is a DELTA representation with no base representation */ + svn_fs_fs__rep_self_delta, + + /* this is a DELTA representation against some base representation */ + svn_fs_fs__rep_delta +} svn_fs_fs__rep_type_t; + +/* This structure is used to hold the information stored in a representation + * header. */ +typedef struct svn_fs_fs__rep_header_t +{ + /* type of the representation, i.e. whether it is PLAIN, self-DELTA etc. */ + svn_fs_fs__rep_type_t type; + + /* if this rep is a delta against some other rep, that base rep can + * be found in this revision. Should be 0 if there is no base rep. */ + svn_revnum_t base_revision; + + /* if this rep is a delta against some other rep, that base rep can + * be found at this item index within the base rep's revision. Should + * be 0 if there is no base rep. */ + apr_off_t base_item_index; + + /* if this rep is a delta against some other rep, this is the (deltified) + * size of that base rep. Should be 0 if there is no base rep. */ + svn_filesize_t base_length; + + /* length of the textual representation of the header in the rep or pack + * file, including EOL. Only valid after reading it from disk. + * Should be 0 otherwise. */ + apr_size_t header_size; +} svn_fs_fs__rep_header_t; + +/* Read the next line from STREAM and parse it as a text + representation header. Return the parsed entry in *HEADER, allocated + in RESULT_POOL. Perform temporary allocations in SCRATCH_POOL. */ +svn_error_t * +svn_fs_fs__read_rep_header(svn_fs_fs__rep_header_t **header, + svn_stream_t *stream, + apr_pool_t *result_pool, + apr_pool_t *scratch_pool); + +/* Write the representation HEADER to STREAM. + * Use SCRATCH_POOL for temporary allocations. */ +svn_error_t * +svn_fs_fs__write_rep_header(svn_fs_fs__rep_header_t *header, + svn_stream_t *stream, + apr_pool_t *scratch_pool); |