1 /* cached_data.c --- cached (read) access to FSFS data
3 * ====================================================================
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
12 * http://www.apache.org/licenses/LICENSE-2.0
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
20 * ====================================================================
23 #include "cached_data.h"
28 #include "svn_ctype.h"
29 #include "svn_sorts.h"
30 #include "private/svn_delta_private.h"
31 #include "private/svn_io_private.h"
32 #include "private/svn_sorts_private.h"
33 #include "private/svn_subr_private.h"
34 #include "private/svn_temp_serializer.h"
39 #include "low_level.h"
42 #include "temp_serializer.h"
44 #include "../libsvn_fs/fs-loader.h"
45 #include "../libsvn_delta/delta.h" /* for SVN_DELTA_WINDOW_SIZE */
47 #include "svn_private_config.h"
49 /* forward-declare. See implementation for the docstring */
51 block_read(void **result,
53 svn_revnum_t revision,
54 apr_uint64_t item_index,
55 svn_fs_fs__revision_file_t *revision_file,
56 apr_pool_t *result_pool,
57 apr_pool_t *scratch_pool);
60 /* Defined this to enable access logging via dgb__log_access
61 #define SVN_FS_FS__LOG_ACCESS
64 /* When SVN_FS_FS__LOG_ACCESS has been defined, write a line to console
65 * showing where REVISION, ITEM_INDEX is located in FS and use ITEM to
66 * show details on it's contents if not NULL. To support format 6 and
67 * earlier repos, ITEM_TYPE (SVN_FS_FS__ITEM_TYPE_*) must match ITEM.
68 * Use SCRATCH_POOL for temporary allocations.
70 * For pre-format7 repos, the display will be restricted.
73 dbg_log_access(svn_fs_t *fs,
74 svn_revnum_t revision,
75 apr_uint64_t item_index,
77 apr_uint32_t item_type,
78 apr_pool_t *scratch_pool)
80 /* no-op if this macro is not defined */
81 #ifdef SVN_FS_FS__LOG_ACCESS
82 fs_fs_data_t *ffd = fs->fsap_data;
83 apr_off_t end_offset = 0;
84 svn_fs_fs__p2l_entry_t *entry = NULL;
85 static const char *types[] = {"<n/a>", "frep ", "drep ", "fprop", "dprop",
86 "node ", "chgs ", "rep "};
87 const char *description = "";
88 const char *type = types[item_type];
89 const char *pack = "";
91 svn_fs_fs__revision_file_t *rev_file;
93 SVN_ERR(svn_fs_fs__open_pack_or_rev_file(&rev_file, fs, revision,
96 /* determine rev / pack file offset */
97 SVN_ERR(svn_fs_fs__item_offset(&offset, fs, rev_file, revision, NULL,
98 item_index, scratch_pool));
100 /* constructing the pack file description */
101 if (revision < ffd->min_unpacked_rev)
102 pack = apr_psprintf(scratch_pool, "%4ld|",
103 revision / ffd->max_files_per_dir);
105 /* construct description if possible */
106 if (item_type == SVN_FS_FS__ITEM_TYPE_NODEREV && item != NULL)
108 node_revision_t *node = item;
111 ? apr_psprintf(scratch_pool, " d=%ld/%" APR_UINT64_T_FMT,
112 node->data_rep->revision,
113 node->data_rep->item_index)
117 ? apr_psprintf(scratch_pool, " p=%ld/%" APR_UINT64_T_FMT,
118 node->prop_rep->revision,
119 node->prop_rep->item_index)
121 description = apr_psprintf(scratch_pool, "%s (pc=%d%s%s)",
123 node->predecessor_count,
127 else if (item_type == SVN_FS_FS__ITEM_TYPE_ANY_REP)
129 svn_fs_fs__rep_header_t *header = item;
131 description = " (txdelta window)";
132 else if (header->type == svn_fs_fs__rep_plain)
133 description = " PLAIN";
134 else if (header->type == svn_fs_fs__rep_self_delta)
135 description = " DELTA";
137 description = apr_psprintf(scratch_pool,
138 " DELTA against %ld/%" APR_UINT64_T_FMT,
139 header->base_revision,
140 header->base_item_index);
142 else if (item_type == SVN_FS_FS__ITEM_TYPE_CHANGES && item != NULL)
144 apr_array_header_t *changes = item;
145 switch (changes->nelts)
147 case 0: description = " no change";
149 case 1: description = " 1 change";
151 default: description = apr_psprintf(scratch_pool, " %d changes",
156 /* some info is only available in format7 repos */
157 if (svn_fs_fs__use_log_addressing(fs))
159 /* reverse index lookup: get item description in ENTRY */
160 SVN_ERR(svn_fs_fs__p2l_entry_lookup(&entry, fs, rev_file, revision,
161 offset, scratch_pool));
165 end_offset = offset + entry->size;
166 type = types[entry->type];
170 printf("%5s%4lx:%04lx -%4lx:%04lx %s %7ld %5"APR_UINT64_T_FMT" %s\n",
171 pack, (long)(offset / ffd->block_size),
172 (long)(offset % ffd->block_size),
173 (long)(end_offset / ffd->block_size),
174 (long)(end_offset % ffd->block_size),
175 type, revision, item_index, description);
179 /* reduced logging for format 6 and earlier */
180 printf("%5s%10" APR_UINT64_T_HEX_FMT " %s %7ld %7" APR_UINT64_T_FMT \
182 pack, (apr_uint64_t)(offset), type, revision, item_index,
191 /* Convenience wrapper around svn_io_file_aligned_seek, taking filesystem
192 FS instead of a block size. */
194 aligned_seek(svn_fs_t *fs,
196 apr_off_t *buffer_start,
200 fs_fs_data_t *ffd = fs->fsap_data;
201 return svn_error_trace(svn_io_file_aligned_seek(file, ffd->block_size,
202 buffer_start, offset,
206 /* Open the revision file for revision REV in filesystem FS and store
207 the newly opened file in FILE. Seek to location OFFSET before
208 returning. Perform temporary allocations in POOL. */
210 open_and_seek_revision(svn_fs_fs__revision_file_t **file,
216 svn_fs_fs__revision_file_t *rev_file;
217 apr_off_t offset = -1;
219 SVN_ERR(svn_fs_fs__ensure_revision_exists(rev, fs, pool));
221 SVN_ERR(svn_fs_fs__open_pack_or_rev_file(&rev_file, fs, rev, pool, pool));
222 SVN_ERR(svn_fs_fs__item_offset(&offset, fs, rev_file, rev, NULL, item,
225 SVN_ERR(aligned_seek(fs, rev_file->file, NULL, offset, pool));
232 /* Open the representation REP for a node-revision in filesystem FS, seek
233 to its position and store the newly opened file in FILE. Perform
234 temporary allocations in POOL. */
236 open_and_seek_transaction(svn_fs_fs__revision_file_t **file,
238 representation_t *rep,
243 SVN_ERR(svn_fs_fs__open_proto_rev_file(file, fs, &rep->txn_id, pool, pool));
245 SVN_ERR(svn_fs_fs__item_offset(&offset, fs, NULL, SVN_INVALID_REVNUM,
246 &rep->txn_id, rep->item_index, pool));
247 SVN_ERR(aligned_seek(fs, (*file)->file, NULL, offset, pool));
252 /* Given a node-id ID, and a representation REP in filesystem FS, open
253 the correct file and seek to the correction location. Store this
254 file in *FILE_P. Perform any allocations in POOL. */
256 open_and_seek_representation(svn_fs_fs__revision_file_t **file_p,
258 representation_t *rep,
261 if (! svn_fs_fs__id_txn_used(&rep->txn_id))
262 return open_and_seek_revision(file_p, fs, rep->revision, rep->item_index,
265 return open_and_seek_transaction(file_p, fs, rep, pool);
271 err_dangling_id(svn_fs_t *fs, const svn_fs_id_t *id)
273 svn_string_t *id_str = svn_fs_fs__id_unparse(id, fs->pool);
274 return svn_error_createf
275 (SVN_ERR_FS_ID_NOT_FOUND, 0,
276 _("Reference to non-existent node '%s' in filesystem '%s'"),
277 id_str->data, fs->path);
280 /* Return TRUE, if FS is of a format that supports block-read and the
281 feature has been enabled. */
283 use_block_read(svn_fs_t *fs)
285 fs_fs_data_t *ffd = fs->fsap_data;
286 return svn_fs_fs__use_log_addressing(fs) && ffd->use_block_read;
289 /* Get the node-revision for the node ID in FS.
290 Set *NODEREV_P to the new node-revision structure, allocated in POOL.
291 See svn_fs_fs__get_node_revision, which wraps this and adds another
294 get_node_revision_body(node_revision_t **noderev_p,
296 const svn_fs_id_t *id,
297 apr_pool_t *result_pool,
298 apr_pool_t *scratch_pool)
301 svn_boolean_t is_cached = FALSE;
302 fs_fs_data_t *ffd = fs->fsap_data;
304 if (svn_fs_fs__id_is_txn(id))
308 /* This is a transaction node-rev. Its storage logic is very
309 different from that of rev / pack files. */
310 err = svn_io_file_open(&file,
311 svn_fs_fs__path_txn_node_rev(fs, id,
313 APR_READ | APR_BUFFERED, APR_OS_DEFAULT,
317 if (APR_STATUS_IS_ENOENT(err->apr_err))
319 svn_error_clear(err);
320 return svn_error_trace(err_dangling_id(fs, id));
323 return svn_error_trace(err);
326 SVN_ERR(svn_fs_fs__read_noderev(noderev_p,
327 svn_stream_from_aprfile2(file,
330 result_pool, scratch_pool));
334 svn_fs_fs__revision_file_t *revision_file;
336 /* noderevs in rev / pack files can be cached */
337 const svn_fs_fs__id_part_t *rev_item = svn_fs_fs__id_rev_item(id);
338 pair_cache_key_t key = { 0 };
339 key.revision = rev_item->revision;
340 key.second = rev_item->number;
342 /* Not found or not applicable. Try a noderev cache lookup.
343 * If that succeeds, we are done here. */
344 if (ffd->node_revision_cache)
346 SVN_ERR(svn_cache__get((void **) noderev_p,
348 ffd->node_revision_cache,
355 /* read the data from disk */
356 SVN_ERR(open_and_seek_revision(&revision_file, fs,
361 if (use_block_read(fs))
363 /* block-read will parse the whole block and will also return
364 the one noderev that we need right now. */
365 SVN_ERR(block_read((void **)noderev_p, fs,
374 /* physical addressing mode reading, parsing and caching */
375 SVN_ERR(svn_fs_fs__read_noderev(noderev_p,
376 revision_file->stream,
380 /* Workaround issue #4031: is-fresh-txn-root in revision files. */
381 (*noderev_p)->is_fresh_txn_root = FALSE;
383 /* The noderev is not in cache, yet. Add it, if caching has been enabled. */
384 if (ffd->node_revision_cache)
385 SVN_ERR(svn_cache__set(ffd->node_revision_cache,
391 SVN_ERR(svn_fs_fs__close_revision_file(revision_file));
398 svn_fs_fs__get_node_revision(node_revision_t **noderev_p,
400 const svn_fs_id_t *id,
401 apr_pool_t *result_pool,
402 apr_pool_t *scratch_pool)
404 const svn_fs_fs__id_part_t *rev_item = svn_fs_fs__id_rev_item(id);
406 svn_error_t *err = get_node_revision_body(noderev_p, fs, id,
407 result_pool, scratch_pool);
408 if (err && err->apr_err == SVN_ERR_FS_CORRUPT)
410 svn_string_t *id_string = svn_fs_fs__id_unparse(id, scratch_pool);
411 return svn_error_createf(SVN_ERR_FS_CORRUPT, err,
412 "Corrupt node-revision '%s'",
416 SVN_ERR(dbg_log_access(fs,
420 SVN_FS_FS__ITEM_TYPE_NODEREV,
423 return svn_error_trace(err);
427 /* Given a revision file REV_FILE, opened to REV in FS, find the Node-ID
428 of the header located at OFFSET and store it in *ID_P. Allocate
429 temporary variables from POOL. */
431 get_fs_id_at_offset(svn_fs_id_t **id_p,
432 svn_fs_fs__revision_file_t *rev_file,
438 node_revision_t *noderev;
440 SVN_ERR(aligned_seek(fs, rev_file->file, NULL, offset, pool));
441 SVN_ERR(svn_fs_fs__read_noderev(&noderev,
445 /* noderev->id is const, get rid of that */
446 *id_p = svn_fs_fs__id_copy(noderev->id, pool);
448 /* assert that the txn_id is REV
449 * (asserting on offset would be harder because we the rev_offset is not
451 assert(svn_fs_fs__id_rev(*id_p) == rev);
457 /* Given an open revision file REV_FILE in FS for REV, locate the trailer that
458 specifies the offset to the root node-id and to the changed path
459 information. Store the root node offset in *ROOT_OFFSET and the
460 changed path offset in *CHANGES_OFFSET. If either of these
461 pointers is NULL, do nothing with it.
463 Allocate temporary variables from POOL. */
465 get_root_changes_offset(apr_off_t *root_offset,
466 apr_off_t *changes_offset,
467 svn_fs_fs__revision_file_t *rev_file,
472 fs_fs_data_t *ffd = fs->fsap_data;
473 apr_off_t rev_offset;
474 apr_seek_where_t seek_relative;
475 svn_stringbuf_t *trailer;
481 /* Determine where to seek to in the file.
483 If we've got a pack file, we want to seek to the end of the desired
484 revision. But we don't track that, so we seek to the beginning of the
487 Unless the next revision is in a different file, in which case, we can
488 just seek to the end of the pack file -- just like we do in the
490 if (rev_file->is_packed && ((rev + 1) % ffd->max_files_per_dir != 0))
492 SVN_ERR(svn_fs_fs__get_packed_offset(&end, fs, rev + 1, pool));
493 seek_relative = APR_SET;
497 seek_relative = APR_END;
501 /* Offset of the revision from the start of the pack file, if applicable. */
502 if (rev_file->is_packed)
503 SVN_ERR(svn_fs_fs__get_packed_offset(&rev_offset, fs, rev, pool));
507 /* We will assume that the last line containing the two offsets
508 will never be longer than 64 characters. */
509 SVN_ERR(svn_io_file_seek(rev_file->file, seek_relative, &end, pool));
511 if (end < sizeof(buffer))
513 len = (apr_size_t)end;
518 len = sizeof(buffer);
519 start = end - sizeof(buffer);
522 /* Read in this last block, from which we will identify the last line. */
523 SVN_ERR(aligned_seek(fs, rev_file->file, NULL, start, pool));
524 SVN_ERR(svn_io_file_read_full2(rev_file->file, buffer, len, NULL, NULL,
527 /* Parse the last line. */
528 trailer = svn_stringbuf_ncreate(buffer, len, pool);
529 SVN_ERR(svn_fs_fs__parse_revision_trailer(root_offset,
534 /* return absolute offsets */
536 *root_offset += rev_offset;
538 *changes_offset += rev_offset;
544 svn_fs_fs__rev_get_root(svn_fs_id_t **root_id_p,
547 apr_pool_t *result_pool,
548 apr_pool_t *scratch_pool)
550 fs_fs_data_t *ffd = fs->fsap_data;
551 SVN_ERR(svn_fs_fs__ensure_revision_exists(rev, fs, scratch_pool));
553 if (svn_fs_fs__use_log_addressing(fs))
555 *root_id_p = svn_fs_fs__id_create_root(rev, result_pool);
559 svn_fs_fs__revision_file_t *revision_file;
560 apr_off_t root_offset;
561 svn_fs_id_t *root_id = NULL;
562 svn_boolean_t is_cached;
564 SVN_ERR(svn_cache__get((void **) root_id_p, &is_cached,
565 ffd->rev_root_id_cache, &rev, result_pool));
569 SVN_ERR(svn_fs_fs__open_pack_or_rev_file(&revision_file, fs, rev,
570 scratch_pool, scratch_pool));
571 SVN_ERR(get_root_changes_offset(&root_offset, NULL,
572 revision_file, fs, rev,
575 SVN_ERR(get_fs_id_at_offset(&root_id, revision_file, fs, rev,
576 root_offset, result_pool));
578 SVN_ERR(svn_fs_fs__close_revision_file(revision_file));
580 SVN_ERR(svn_cache__set(ffd->rev_root_id_cache, &rev, root_id,
583 *root_id_p = root_id;
589 /* Describes a lazily opened rev / pack file. Instances will be shared
590 between multiple instances of rep_state_t. */
591 typedef struct shared_file_t
593 /* The opened file. NULL while file is not open, yet. */
594 svn_fs_fs__revision_file_t *rfile;
596 /* file system to open the file in */
599 /* a revision contained in the FILE. Since this file may be shared,
600 that value may be different from REP_STATE_T->REVISION. */
601 svn_revnum_t revision;
603 /* pool to use when creating the FILE. This guarantees that the file
604 remains open / valid beyond the respective local context that required
605 the file to be opened eventually. */
609 /* Represents where in the current svndiff data block each
610 representation is. */
611 typedef struct rep_state_t
613 /* shared lazy-open rev/pack file structure */
614 shared_file_t *sfile;
615 /* The txdelta window cache to use or NULL. */
616 svn_cache__t *raw_window_cache;
617 /* Caches raw (unparsed) windows. May be NULL. */
618 svn_cache__t *window_cache;
619 /* Caches un-deltified windows. May be NULL. */
620 svn_cache__t *combined_cache;
621 /* revision containing the representation */
622 svn_revnum_t revision;
623 /* representation's item index in REVISION */
624 apr_uint64_t item_index;
625 /* length of the header at the start of the rep.
626 0 iff this is rep is stored in a container
627 (i.e. does not have a header) */
628 apr_size_t header_size;
629 apr_off_t start; /* The starting offset for the raw
630 svndiff/plaintext data minus header.
631 -1 if the offset is yet unknown. */
632 apr_off_t current;/* The current offset relative to START. */
633 apr_off_t size; /* The on-disk size of the representation. */
634 int ver; /* If a delta, what svndiff version?
635 -1 for unknown delta version. */
636 int chunk_index; /* number of the window to read */
639 /* Simple wrapper around svn_fs_fs__get_file_offset to simplify callers. */
641 get_file_offset(apr_off_t *offset,
645 return svn_error_trace(svn_fs_fs__get_file_offset(offset,
646 rs->sfile->rfile->file,
650 /* Simple wrapper around svn_io_file_aligned_seek to simplify callers. */
652 rs_aligned_seek(rep_state_t *rs,
653 apr_off_t *buffer_start,
657 fs_fs_data_t *ffd = rs->sfile->fs->fsap_data;
658 return svn_error_trace(svn_io_file_aligned_seek(rs->sfile->rfile->file,
660 buffer_start, offset,
664 /* Open FILE->FILE and FILE->STREAM if they haven't been opened, yet. */
666 auto_open_shared_file(shared_file_t *file)
668 if (file->rfile == NULL)
669 SVN_ERR(svn_fs_fs__open_pack_or_rev_file(&file->rfile, file->fs,
670 file->revision, file->pool,
676 /* Set RS->START to the begin of the representation raw in RS->FILE->FILE,
677 if that hasn't been done yet. Use POOL for temporary allocations. */
679 auto_set_start_offset(rep_state_t *rs, apr_pool_t *pool)
683 SVN_ERR(svn_fs_fs__item_offset(&rs->start, rs->sfile->fs,
684 rs->sfile->rfile, rs->revision, NULL,
685 rs->item_index, pool));
686 rs->start += rs->header_size;
692 /* Set RS->VER depending on what is found in the already open RS->FILE->FILE
693 if the diff version is still unknown. Use POOL for temporary allocations.
696 auto_read_diff_version(rep_state_t *rs, apr_pool_t *pool)
701 SVN_ERR(rs_aligned_seek(rs, NULL, rs->start, pool));
702 SVN_ERR(svn_io_file_read_full2(rs->sfile->rfile->file, buf,
703 sizeof(buf), NULL, NULL, pool));
705 /* ### Layering violation */
706 if (! ((buf[0] == 'S') && (buf[1] == 'V') && (buf[2] == 'N')))
707 return svn_error_create
708 (SVN_ERR_FS_CORRUPT, NULL,
709 _("Malformed svndiff data in representation"));
719 /* See create_rep_state, which wraps this and adds another error. */
721 create_rep_state_body(rep_state_t **rep_state,
722 svn_fs_fs__rep_header_t **rep_header,
723 shared_file_t **shared_file,
724 representation_t *rep,
726 apr_pool_t *result_pool,
727 apr_pool_t *scratch_pool)
729 fs_fs_data_t *ffd = fs->fsap_data;
730 rep_state_t *rs = apr_pcalloc(result_pool, sizeof(*rs));
731 svn_fs_fs__rep_header_t *rh;
732 svn_boolean_t is_cached = FALSE;
733 apr_uint64_t estimated_window_storage;
737 * - refers to a valid revision,
738 * - refers to a packed revision,
739 * - as does the rep we want to read, and
740 * - refers to the same pack file as the rep
741 * we can re-use the same, already open file object
743 svn_boolean_t reuse_shared_file
744 = shared_file && *shared_file && (*shared_file)->rfile
745 && SVN_IS_VALID_REVNUM((*shared_file)->revision)
746 && (*shared_file)->revision < ffd->min_unpacked_rev
747 && rep->revision < ffd->min_unpacked_rev
748 && ( ((*shared_file)->revision / ffd->max_files_per_dir)
749 == (rep->revision / ffd->max_files_per_dir));
751 pair_cache_key_t key;
752 key.revision = rep->revision;
753 key.second = rep->item_index;
755 /* continue constructing RS and RA */
756 rs->size = rep->size;
757 rs->revision = rep->revision;
758 rs->item_index = rep->item_index;
759 rs->raw_window_cache = ffd->raw_window_cache;
763 /* Very long files stored as self-delta will produce a huge number of
764 delta windows. Don't cache them lest we don't thrash the cache.
765 Since we don't know the depth of the delta chain, let's assume, the
766 whole contents get rewritten 3 times.
768 estimated_window_storage
769 = 4 * ( (rep->expanded_size ? rep->expanded_size : rep->size)
770 + SVN_DELTA_WINDOW_SIZE);
771 estimated_window_storage = MIN(estimated_window_storage, APR_SIZE_MAX);
773 rs->window_cache = ffd->txdelta_window_cache
774 && svn_cache__is_cachable(ffd->txdelta_window_cache,
775 (apr_size_t)estimated_window_storage)
776 ? ffd->txdelta_window_cache
778 rs->combined_cache = ffd->combined_window_cache
779 && svn_cache__is_cachable(ffd->combined_window_cache,
780 (apr_size_t)estimated_window_storage)
781 ? ffd->combined_window_cache
784 /* cache lookup, i.e. skip reading the rep header if possible */
785 if (ffd->rep_header_cache && !svn_fs_fs__id_txn_used(&rep->txn_id))
786 SVN_ERR(svn_cache__get((void **) &rh, &is_cached,
787 ffd->rep_header_cache, &key, result_pool));
789 /* initialize the (shared) FILE member in RS */
790 if (reuse_shared_file)
792 rs->sfile = *shared_file;
796 shared_file_t *file = apr_pcalloc(result_pool, sizeof(*file));
797 file->revision = rep->revision;
798 file->pool = result_pool;
802 /* remember the current file, if suggested by the caller */
807 /* read rep header, if necessary */
810 /* ensure file is open and navigate to the start of rep header */
811 if (reuse_shared_file)
815 /* ... we can re-use the same, already open file object.
816 * This implies that we don't read from a txn.
818 rs->sfile = *shared_file;
819 SVN_ERR(auto_open_shared_file(rs->sfile));
820 SVN_ERR(svn_fs_fs__item_offset(&offset, fs, rs->sfile->rfile,
821 rep->revision, NULL, rep->item_index,
823 SVN_ERR(rs_aligned_seek(rs, NULL, offset, scratch_pool));
827 /* otherwise, create a new file object. May or may not be
830 SVN_ERR(open_and_seek_representation(&rs->sfile->rfile, fs, rep,
834 SVN_ERR(svn_fs_fs__read_rep_header(&rh, rs->sfile->rfile->stream,
835 result_pool, scratch_pool));
836 SVN_ERR(get_file_offset(&rs->start, rs, result_pool));
838 /* populate the cache if appropriate */
839 if (! svn_fs_fs__id_txn_used(&rep->txn_id))
841 if (use_block_read(fs))
842 SVN_ERR(block_read(NULL, fs, rep->revision, rep->item_index,
843 rs->sfile->rfile, result_pool, scratch_pool));
845 if (ffd->rep_header_cache)
846 SVN_ERR(svn_cache__set(ffd->rep_header_cache, &key, rh,
852 SVN_ERR(dbg_log_access(fs, rep->revision, rep->item_index, rh,
853 SVN_FS_FS__ITEM_TYPE_ANY_REP, scratch_pool));
855 rs->header_size = rh->header_size;
859 if (rh->type == svn_fs_fs__rep_plain)
860 /* This is a plaintext, so just return the current rep_state. */
863 /* skip "SVNx" diff marker */
869 /* Read the rep args for REP in filesystem FS and create a rep_state
870 for reading the representation. Return the rep_state in *REP_STATE
871 and the rep header in *REP_HEADER, both allocated in POOL.
873 When reading multiple reps, i.e. a skip delta chain, you may provide
874 non-NULL SHARED_FILE. (If SHARED_FILE is not NULL, in the first
875 call it should be a pointer to NULL.) The function will use this
876 variable to store the previous call results and tries to re-use it.
877 This may result in significant savings in I/O for packed files and
878 number of open file handles.
881 create_rep_state(rep_state_t **rep_state,
882 svn_fs_fs__rep_header_t **rep_header,
883 shared_file_t **shared_file,
884 representation_t *rep,
886 apr_pool_t *result_pool,
887 apr_pool_t *scratch_pool)
889 svn_error_t *err = create_rep_state_body(rep_state, rep_header,
890 shared_file, rep, fs,
891 result_pool, scratch_pool);
892 if (err && err->apr_err == SVN_ERR_FS_CORRUPT)
894 fs_fs_data_t *ffd = fs->fsap_data;
897 /* ### This always returns "-1" for transaction reps, because
898 ### this particular bit of code doesn't know if the rep is
899 ### stored in the protorev or in the mutable area (for props
900 ### or dir contents). It is pretty rare for FSFS to *read*
901 ### from the protorev file, though, so this is probably OK.
902 ### And anyone going to debug corruption errors is probably
903 ### going to jump straight to this comment anyway! */
905 ? svn_fs_fs__unparse_representation
906 (rep, ffd->format, TRUE, scratch_pool, scratch_pool)->data
909 return svn_error_createf(SVN_ERR_FS_CORRUPT, err,
910 "Corrupt representation '%s'",
913 /* ### Call representation_string() ? */
914 return svn_error_trace(err);
918 svn_fs_fs__check_rep(representation_t *rep,
921 apr_pool_t *scratch_pool)
923 if (svn_fs_fs__use_log_addressing(fs))
926 svn_fs_fs__p2l_entry_t *entry;
927 svn_fs_fs__revision_file_t *rev_file = NULL;
929 /* Reuse the revision file provided by *HINT, if it is given and
930 * actually the rev / pack file that we want. */
931 svn_revnum_t start_rev = svn_fs_fs__packed_base_rev(fs, rep->revision);
933 rev_file = *(svn_fs_fs__revision_file_t **)hint;
935 if (rev_file == NULL || rev_file->start_revision != start_rev)
936 SVN_ERR(svn_fs_fs__open_pack_or_rev_file(&rev_file, fs, rep->revision,
937 scratch_pool, scratch_pool));
942 /* This will auto-retry if there was a background pack. */
943 SVN_ERR(svn_fs_fs__item_offset(&offset, fs, rev_file, rep->revision,
944 NULL, rep->item_index, scratch_pool));
946 /* This may fail if there is a background pack operation (can't auto-
947 retry because the item offset lookup has to be redone as well). */
948 SVN_ERR(svn_fs_fs__p2l_entry_lookup(&entry, fs, rev_file,
949 rep->revision, offset,
950 scratch_pool, scratch_pool));
953 || entry->type < SVN_FS_FS__ITEM_TYPE_FILE_REP
954 || entry->type > SVN_FS_FS__ITEM_TYPE_DIR_PROPS)
955 return svn_error_createf(SVN_ERR_FS_CORRUPT, NULL,
956 _("No representation found at offset %s "
957 "for item %s in revision %ld"),
958 apr_off_t_toa(scratch_pool, offset),
959 apr_psprintf(scratch_pool,
960 "%" APR_UINT64_T_FMT,
967 svn_fs_fs__rep_header_t *rep_header;
969 /* ### Should this be using read_rep_line() directly? */
970 SVN_ERR(create_rep_state(&rs, &rep_header, (shared_file_t**)hint,
971 rep, fs, scratch_pool, scratch_pool));
978 svn_fs_fs__rep_chain_length(int *chain_length,
980 representation_t *rep,
982 apr_pool_t *scratch_pool)
984 fs_fs_data_t *ffd = fs->fsap_data;
985 svn_revnum_t shard_size = ffd->max_files_per_dir
986 ? ffd->max_files_per_dir
988 apr_pool_t *subpool = svn_pool_create(scratch_pool);
989 apr_pool_t *iterpool = svn_pool_create(scratch_pool);
990 svn_boolean_t is_delta = FALSE;
993 svn_revnum_t last_shard = rep->revision / shard_size;
995 /* Check whether the length of the deltification chain is acceptable.
996 * Otherwise, shared reps may form a non-skipping delta chain in
998 representation_t base_rep = *rep;
1000 /* re-use open files between iterations */
1001 shared_file_t *file_hint = NULL;
1003 svn_fs_fs__rep_header_t *header;
1005 /* follow the delta chain towards the end but for at most
1006 * MAX_CHAIN_LENGTH steps. */
1009 rep_state_t *rep_state;
1011 svn_pool_clear(iterpool);
1013 if (base_rep.revision / shard_size != last_shard)
1015 last_shard = base_rep.revision / shard_size;
1019 SVN_ERR(create_rep_state_body(&rep_state,
1027 base_rep.revision = header->base_revision;
1028 base_rep.item_index = header->base_item_index;
1029 base_rep.size = header->base_length;
1030 svn_fs_fs__id_txn_reset(&base_rep.txn_id);
1031 is_delta = header->type == svn_fs_fs__rep_delta;
1033 /* Clear it the SUBPOOL once in a while. Doing it too frequently
1034 * renders the FILE_HINT ineffective. Doing too infrequently, may
1035 * leave us with too many open file handles.
1037 * Note that this is mostly about efficiency, with larger values
1038 * being more efficient, and any non-zero value is legal here. When
1039 * reading deltified contents, we may keep 10s of rev files open at
1040 * the same time and the system has to cope with that. Thus, the
1041 * limit of 16 chosen below is in the same ballpark.
1044 if (count % 16 == 0)
1047 svn_pool_clear(subpool);
1050 while (is_delta && base_rep.revision);
1052 *chain_length = count;
1053 *shard_count = shards;
1054 svn_pool_destroy(subpool);
1055 svn_pool_destroy(iterpool);
1057 return SVN_NO_ERROR;
1060 struct rep_read_baton
1062 /* The FS from which we're reading. */
1065 /* Representation to read. */
1066 representation_t rep;
1068 /* If not NULL, this is the base for the first delta window in rs_list */
1069 svn_stringbuf_t *base_window;
1071 /* The state of all prior delta representations. */
1072 apr_array_header_t *rs_list;
1074 /* The plaintext state, if there is a plaintext. */
1075 rep_state_t *src_state;
1077 /* The index of the current delta chunk, if we are reading a delta. */
1080 /* The buffer where we store undeltified data. */
1085 /* A checksum context for summing the data read in order to verify it.
1086 Note: we don't need to use the sha1 checksum because we're only doing
1087 data verification, for which md5 is perfectly safe. */
1088 svn_checksum_ctx_t *md5_checksum_ctx;
1090 svn_boolean_t checksum_finalized;
1092 /* The stored checksum of the representation we are reading, its
1093 length, and the amount we've read so far. Some of this
1094 information is redundant with rs_list and src_state, but it's
1095 convenient for the checksumming code to have it here. */
1096 unsigned char md5_digest[APR_MD5_DIGESTSIZE];
1101 /* The key for the fulltext cache for this rep, if there is a
1103 pair_cache_key_t fulltext_cache_key;
1104 /* The text we've been reading, if we're going to cache it. */
1105 svn_stringbuf_t *current_fulltext;
1107 /* If not NULL, attempt to read the data from this cache.
1108 Once that lookup fails, reset it to NULL. */
1109 svn_cache__t *fulltext_cache;
1111 /* Bytes delivered from the FULLTEXT_CACHE so far. If the next
1112 lookup fails, we need to skip that much data from the reconstructed
1113 window stream before we continue normal operation. */
1114 svn_filesize_t fulltext_delivered;
1116 /* Used for temporary allocations during the read. */
1119 /* Pool used to store file handles and other data that is persistant
1120 for the entire stream read. */
1121 apr_pool_t *filehandle_pool;
1124 /* Set window key in *KEY to address the window described by RS.
1125 For convenience, return the KEY. */
1126 static window_cache_key_t *
1127 get_window_key(window_cache_key_t *key, rep_state_t *rs)
1129 assert(rs->revision <= APR_UINT32_MAX);
1130 key->revision = (apr_uint32_t)rs->revision;
1131 key->item_index = rs->item_index;
1132 key->chunk_index = rs->chunk_index;
1137 /* Implement svn_cache__partial_getter_func_t for raw txdelta windows.
1138 * Parse the raw data and return a svn_fs_fs__txdelta_cached_window_t.
1140 static svn_error_t *
1141 parse_raw_window(void **out,
1143 apr_size_t data_len,
1145 apr_pool_t *result_pool)
1147 svn_string_t raw_window;
1148 svn_stream_t *stream;
1150 /* unparsed and parsed window */
1151 const svn_fs_fs__raw_cached_window_t *window
1152 = (const svn_fs_fs__raw_cached_window_t *)data;
1153 svn_fs_fs__txdelta_cached_window_t *result
1154 = apr_pcalloc(result_pool, sizeof(*result));
1156 /* create a read stream taking the raw window as input */
1157 raw_window.data = svn_temp_deserializer__ptr(window,
1158 (const void * const *)&window->window.data);
1159 raw_window.len = window->window.len;
1160 stream = svn_stream_from_string(&raw_window, result_pool);
1163 SVN_ERR(svn_txdelta_read_svndiff_window(&result->window, stream, 1,
1166 /* complete the window and return it */
1167 result->end_offset = window->end_offset;
1170 return SVN_NO_ERROR;
1174 /* Read the WINDOW_P number CHUNK_INDEX for the representation given in
1175 * rep state RS from the current FSFS session's cache. This will be a
1176 * no-op and IS_CACHED will be set to FALSE if no cache has been given.
1177 * If a cache is available IS_CACHED will inform the caller about the
1178 * success of the lookup. Allocations of the window in will be made
1179 * from RESULT_POOL. Use SCRATCH_POOL for temporary allocations.
1181 * If the information could be found, put RS to CHUNK_INDEX.
1183 static svn_error_t *
1184 get_cached_window(svn_txdelta_window_t **window_p,
1187 svn_boolean_t *is_cached,
1188 apr_pool_t *result_pool,
1189 apr_pool_t *scratch_pool)
1191 if (! rs->window_cache)
1193 /* txdelta window has not been enabled */
1198 /* ask the cache for the desired txdelta window */
1199 svn_fs_fs__txdelta_cached_window_t *cached_window;
1200 window_cache_key_t key = { 0 };
1201 get_window_key(&key, rs);
1202 key.chunk_index = chunk_index;
1203 SVN_ERR(svn_cache__get((void **) &cached_window,
1209 /* If we did not find a parsed txdelta window, we might have a raw
1210 version of it in our cache. If so, read, parse and re-cache it. */
1211 if (!*is_cached && rs->raw_window_cache)
1213 SVN_ERR(svn_cache__get_partial((void **) &cached_window, is_cached,
1214 rs->raw_window_cache, &key,
1215 parse_raw_window, NULL, result_pool));
1217 SVN_ERR(svn_cache__set(rs->window_cache, &key, cached_window,
1221 /* Return cached information. */
1224 /* found it. Pass it back to the caller. */
1225 *window_p = cached_window->window;
1227 /* manipulate the RS as if we just read the data */
1228 rs->current = cached_window->end_offset;
1229 rs->chunk_index = chunk_index;
1233 return SVN_NO_ERROR;
1236 /* Store the WINDOW read for the rep state RS in the current FSFS
1237 * session's cache. This will be a no-op if no cache has been given.
1238 * Temporary allocations will be made from SCRATCH_POOL. */
1239 static svn_error_t *
1240 set_cached_window(svn_txdelta_window_t *window,
1242 apr_pool_t *scratch_pool)
1244 if (rs->window_cache)
1246 /* store the window and the first offset _past_ it */
1247 svn_fs_fs__txdelta_cached_window_t cached_window;
1248 window_cache_key_t key = {0};
1250 cached_window.window = window;
1251 cached_window.end_offset = rs->current;
1253 /* but key it with the start offset because that is the known state
1254 * when we will look it up */
1255 SVN_ERR(svn_cache__set(rs->window_cache,
1256 get_window_key(&key, rs),
1261 return SVN_NO_ERROR;
1264 /* Read the WINDOW_P for the rep state RS from the current FSFS session's
1265 * cache. This will be a no-op and IS_CACHED will be set to FALSE if no
1266 * cache has been given. If a cache is available IS_CACHED will inform
1267 * the caller about the success of the lookup. Allocations (of the window
1268 * in particular) will be made from POOL.
1270 static svn_error_t *
1271 get_cached_combined_window(svn_stringbuf_t **window_p,
1273 svn_boolean_t *is_cached,
1276 if (! rs->combined_cache)
1278 /* txdelta window has not been enabled */
1283 /* ask the cache for the desired txdelta window */
1284 window_cache_key_t key = { 0 };
1285 return svn_cache__get((void **)window_p,
1288 get_window_key(&key, rs),
1292 return SVN_NO_ERROR;
1295 /* Store the WINDOW read for the rep state RS in the current FSFS session's
1296 * cache. This will be a no-op if no cache has been given.
1297 * Temporary allocations will be made from SCRATCH_POOL. */
1298 static svn_error_t *
1299 set_cached_combined_window(svn_stringbuf_t *window,
1301 apr_pool_t *scratch_pool)
1303 if (rs->combined_cache)
1305 /* but key it with the start offset because that is the known state
1306 * when we will look it up */
1307 window_cache_key_t key = { 0 };
1308 return svn_cache__set(rs->combined_cache,
1309 get_window_key(&key, rs),
1314 return SVN_NO_ERROR;
1317 /* Build an array of rep_state structures in *LIST giving the delta
1318 reps from first_rep to a plain-text or self-compressed rep. Set
1319 *SRC_STATE to the plain-text rep we find at the end of the chain,
1320 or to NULL if the final delta representation is self-compressed.
1321 The representation to start from is designated by filesystem FS, id
1322 ID, and representation REP.
1323 Also, set *WINDOW_P to the base window content for *LIST, if it
1324 could be found in cache. Otherwise, *LIST will contain the base
1325 representation for the whole delta chain.
1326 Finally, return the expanded size of the representation in
1327 *EXPANDED_SIZE. It will take care of cases where only the on-disk
1329 static svn_error_t *
1330 build_rep_list(apr_array_header_t **list,
1331 svn_stringbuf_t **window_p,
1332 rep_state_t **src_state,
1333 svn_filesize_t *expanded_size,
1335 representation_t *first_rep,
1338 representation_t rep;
1339 rep_state_t *rs = NULL;
1340 svn_fs_fs__rep_header_t *rep_header;
1341 svn_boolean_t is_cached = FALSE;
1342 shared_file_t *shared_file = NULL;
1343 apr_pool_t *iterpool = svn_pool_create(pool);
1345 *list = apr_array_make(pool, 1, sizeof(rep_state_t *));
1348 /* The value as stored in the data struct.
1349 0 is either for unknown length or actually zero length. */
1350 *expanded_size = first_rep->expanded_size;
1352 /* for the top-level rep, we need the rep_args */
1353 SVN_ERR(create_rep_state(&rs, &rep_header, &shared_file, &rep, fs, pool,
1356 /* Unknown size or empty representation?
1357 That implies the this being the first iteration.
1358 Usually size equals on-disk size, except for empty,
1359 compressed representations (delta, size = 4).
1360 Please note that for all non-empty deltas have
1361 a 4-byte header _plus_ some data. */
1362 if (*expanded_size == 0)
1363 if (rep_header->type == svn_fs_fs__rep_plain || first_rep->size != 4)
1364 *expanded_size = first_rep->size;
1368 svn_pool_clear(iterpool);
1370 /* fetch state, if that has not been done already */
1372 SVN_ERR(create_rep_state(&rs, &rep_header, &shared_file,
1373 &rep, fs, pool, iterpool));
1375 /* for txn reps, there won't be a cached combined window */
1376 if (!svn_fs_fs__id_txn_used(&rep.txn_id))
1377 SVN_ERR(get_cached_combined_window(window_p, rs, &is_cached, pool));
1381 /* We already have a reconstructed window in our cache.
1382 Write a pseudo rep_state with the full length. */
1385 rs->size = (*window_p)->len;
1390 if (rep_header->type == svn_fs_fs__rep_plain)
1392 /* This is a plaintext, so just return the current rep_state. */
1397 /* Push this rep onto the list. If it's self-compressed, we're done. */
1398 APR_ARRAY_PUSH(*list, rep_state_t *) = rs;
1399 if (rep_header->type == svn_fs_fs__rep_self_delta)
1405 rep.revision = rep_header->base_revision;
1406 rep.item_index = rep_header->base_item_index;
1407 rep.size = rep_header->base_length;
1408 svn_fs_fs__id_txn_reset(&rep.txn_id);
1412 svn_pool_destroy(iterpool);
1414 return SVN_NO_ERROR;
1418 /* Create a rep_read_baton structure for node revision NODEREV in
1419 filesystem FS and store it in *RB_P. Perform all allocations in
1420 POOL. If rep is mutable, it must be for file contents. */
1421 static svn_error_t *
1422 rep_read_get_baton(struct rep_read_baton **rb_p,
1424 representation_t *rep,
1425 pair_cache_key_t fulltext_cache_key,
1428 struct rep_read_baton *b;
1430 b = apr_pcalloc(pool, sizeof(*b));
1433 b->base_window = NULL;
1436 b->md5_checksum_ctx = svn_checksum_ctx_create(svn_checksum_md5, pool);
1437 b->checksum_finalized = FALSE;
1438 memcpy(b->md5_digest, rep->md5_digest, sizeof(rep->md5_digest));
1439 b->len = rep->expanded_size;
1441 b->fulltext_cache_key = fulltext_cache_key;
1442 b->pool = svn_pool_create(pool);
1443 b->filehandle_pool = svn_pool_create(pool);
1444 b->fulltext_cache = NULL;
1445 b->fulltext_delivered = 0;
1446 b->current_fulltext = NULL;
1448 /* Save our output baton. */
1451 return SVN_NO_ERROR;
1454 /* Skip forwards to THIS_CHUNK in REP_STATE and then read the next delta
1455 window into *NWIN. Note that RS->CHUNK_INDEX will be THIS_CHUNK rather
1456 than THIS_CHUNK + 1 when this function returns. */
1457 static svn_error_t *
1458 read_delta_window(svn_txdelta_window_t **nwin, int this_chunk,
1459 rep_state_t *rs, apr_pool_t *result_pool,
1460 apr_pool_t *scratch_pool)
1462 svn_boolean_t is_cached;
1463 apr_off_t start_offset;
1464 apr_off_t end_offset;
1465 apr_pool_t *iterpool;
1467 SVN_ERR_ASSERT(rs->chunk_index <= this_chunk);
1469 SVN_ERR(dbg_log_access(rs->sfile->fs, rs->revision, rs->item_index,
1470 NULL, SVN_FS_FS__ITEM_TYPE_ANY_REP, scratch_pool));
1472 /* Read the next window. But first, try to find it in the cache. */
1473 SVN_ERR(get_cached_window(nwin, rs, this_chunk, &is_cached,
1474 result_pool, scratch_pool));
1476 return SVN_NO_ERROR;
1478 /* someone has to actually read the data from file. Open it */
1479 SVN_ERR(auto_open_shared_file(rs->sfile));
1481 /* invoke the 'block-read' feature for non-txn data.
1482 However, don't do that if we are in the middle of some representation,
1483 because the block is unlikely to contain other data. */
1484 if ( rs->chunk_index == 0
1485 && SVN_IS_VALID_REVNUM(rs->revision)
1486 && use_block_read(rs->sfile->fs)
1487 && rs->raw_window_cache)
1489 SVN_ERR(block_read(NULL, rs->sfile->fs, rs->revision, rs->item_index,
1490 rs->sfile->rfile, result_pool, scratch_pool));
1492 /* reading the whole block probably also provided us with the
1493 desired txdelta window */
1494 SVN_ERR(get_cached_window(nwin, rs, this_chunk, &is_cached,
1495 result_pool, scratch_pool));
1497 return SVN_NO_ERROR;
1500 /* data is still not cached -> we need to read it.
1501 Make sure we have all the necessary info. */
1502 SVN_ERR(auto_set_start_offset(rs, scratch_pool));
1503 SVN_ERR(auto_read_diff_version(rs, scratch_pool));
1505 /* RS->FILE may be shared between RS instances -> make sure we point
1506 * to the right data. */
1507 start_offset = rs->start + rs->current;
1508 SVN_ERR(rs_aligned_seek(rs, NULL, start_offset, scratch_pool));
1510 /* Skip windows to reach the current chunk if we aren't there yet. */
1511 iterpool = svn_pool_create(scratch_pool);
1512 while (rs->chunk_index < this_chunk)
1514 svn_pool_clear(iterpool);
1515 SVN_ERR(svn_txdelta_skip_svndiff_window(rs->sfile->rfile->file,
1516 rs->ver, iterpool));
1518 SVN_ERR(get_file_offset(&start_offset, rs, iterpool));
1519 rs->current = start_offset - rs->start;
1520 if (rs->current >= rs->size)
1521 return svn_error_create(SVN_ERR_FS_CORRUPT, NULL,
1522 _("Reading one svndiff window read "
1523 "beyond the end of the "
1526 svn_pool_destroy(iterpool);
1528 /* Actually read the next window. */
1529 SVN_ERR(svn_txdelta_read_svndiff_window(nwin, rs->sfile->rfile->stream,
1530 rs->ver, result_pool));
1531 SVN_ERR(get_file_offset(&end_offset, rs, scratch_pool));
1532 rs->current = end_offset - rs->start;
1533 if (rs->current > rs->size)
1534 return svn_error_create(SVN_ERR_FS_CORRUPT, NULL,
1535 _("Reading one svndiff window read beyond "
1536 "the end of the representation"));
1538 /* the window has not been cached before, thus cache it now
1539 * (if caching is used for them at all) */
1540 if (SVN_IS_VALID_REVNUM(rs->revision))
1541 SVN_ERR(set_cached_window(*nwin, rs, scratch_pool));
1543 return SVN_NO_ERROR;
1546 /* Read SIZE bytes from the representation RS and return it in *NWIN. */
1547 static svn_error_t *
1548 read_plain_window(svn_stringbuf_t **nwin, rep_state_t *rs,
1549 apr_size_t size, apr_pool_t *result_pool,
1550 apr_pool_t *scratch_pool)
1554 /* RS->FILE may be shared between RS instances -> make sure we point
1555 * to the right data. */
1556 SVN_ERR(auto_open_shared_file(rs->sfile));
1557 SVN_ERR(auto_set_start_offset(rs, scratch_pool));
1559 offset = rs->start + rs->current;
1560 SVN_ERR(rs_aligned_seek(rs, NULL, offset, scratch_pool));
1562 /* Read the plain data. */
1563 *nwin = svn_stringbuf_create_ensure(size, result_pool);
1564 SVN_ERR(svn_io_file_read_full2(rs->sfile->rfile->file, (*nwin)->data, size,
1565 NULL, NULL, result_pool));
1566 (*nwin)->data[size] = 0;
1569 rs->current += (apr_off_t)size;
1571 return SVN_NO_ERROR;
1574 /* Get the undeltified window that is a result of combining all deltas
1575 from the current desired representation identified in *RB with its
1576 base representation. Store the window in *RESULT. */
1577 static svn_error_t *
1578 get_combined_window(svn_stringbuf_t **result,
1579 struct rep_read_baton *rb)
1581 apr_pool_t *pool, *new_pool, *window_pool;
1583 apr_array_header_t *windows;
1584 svn_stringbuf_t *source, *buf = rb->base_window;
1586 apr_pool_t *iterpool;
1588 /* Read all windows that we need to combine. This is fine because
1589 the size of each window is relatively small (100kB) and skip-
1590 delta limits the number of deltas in a chain to well under 100.
1591 Stop early if one of them does not depend on its predecessors. */
1592 window_pool = svn_pool_create(rb->pool);
1593 windows = apr_array_make(window_pool, 0, sizeof(svn_txdelta_window_t *));
1594 iterpool = svn_pool_create(rb->pool);
1595 for (i = 0; i < rb->rs_list->nelts; ++i)
1597 svn_txdelta_window_t *window;
1599 svn_pool_clear(iterpool);
1601 rs = APR_ARRAY_IDX(rb->rs_list, i, rep_state_t *);
1602 SVN_ERR(read_delta_window(&window, rb->chunk_index, rs, window_pool,
1605 APR_ARRAY_PUSH(windows, svn_txdelta_window_t *) = window;
1606 if (window->src_ops == 0)
1613 /* Combine in the windows from the other delta reps. */
1614 pool = svn_pool_create(rb->pool);
1615 for (--i; i >= 0; --i)
1617 svn_txdelta_window_t *window;
1619 svn_pool_clear(iterpool);
1621 rs = APR_ARRAY_IDX(rb->rs_list, i, rep_state_t *);
1622 window = APR_ARRAY_IDX(windows, i, svn_txdelta_window_t *);
1624 /* Maybe, we've got a PLAIN start representation. If we do, read
1625 as much data from it as the needed for the txdelta window's source
1627 Note that BUF / SOURCE may only be NULL in the first iteration.
1628 Also note that we may have short-cut reading the delta chain --
1629 in which case SRC_OPS is 0 and it might not be a PLAIN rep. */
1631 if (source == NULL && rb->src_state != NULL && window->src_ops)
1632 SVN_ERR(read_plain_window(&source, rb->src_state, window->sview_len,
1635 /* Combine this window with the current one. */
1636 new_pool = svn_pool_create(rb->pool);
1637 buf = svn_stringbuf_create_ensure(window->tview_len, new_pool);
1638 buf->len = window->tview_len;
1640 svn_txdelta_apply_instructions(window, source ? source->data : NULL,
1641 buf->data, &buf->len);
1642 if (buf->len != window->tview_len)
1643 return svn_error_create(SVN_ERR_FS_CORRUPT, NULL,
1644 _("svndiff window length is "
1647 /* Cache windows only if the whole rep content could be read as a
1648 single chunk. Only then will no other chunk need a deeper RS
1649 list than the cached chunk. */
1650 if ( (rb->chunk_index == 0) && (rs->current == rs->size)
1651 && SVN_IS_VALID_REVNUM(rs->revision))
1652 SVN_ERR(set_cached_combined_window(buf, rs, new_pool));
1656 /* Cycle pools so that we only need to hold three windows at a time. */
1657 svn_pool_destroy(pool);
1660 svn_pool_destroy(iterpool);
1662 svn_pool_destroy(window_pool);
1665 return SVN_NO_ERROR;
1668 /* Returns whether or not the expanded fulltext of the file is cachable
1669 * based on its size SIZE. The decision depends on the cache used by RB.
1671 static svn_boolean_t
1672 fulltext_size_is_cachable(fs_fs_data_t *ffd, svn_filesize_t size)
1674 return (size < APR_SIZE_MAX)
1675 && svn_cache__is_cachable(ffd->fulltext_cache, (apr_size_t)size);
1678 /* Close method used on streams returned by read_representation().
1680 static svn_error_t *
1681 rep_read_contents_close(void *baton)
1683 struct rep_read_baton *rb = baton;
1685 svn_pool_destroy(rb->pool);
1686 svn_pool_destroy(rb->filehandle_pool);
1688 return SVN_NO_ERROR;
1691 /* Return the next *LEN bytes of the rep from our plain / delta windows
1692 and store them in *BUF. */
1693 static svn_error_t *
1694 get_contents_from_windows(struct rep_read_baton *rb,
1698 apr_size_t copy_len, remaining = *len;
1702 /* Special case for when there are no delta reps, only a plain
1704 if (rb->rs_list->nelts == 0)
1706 copy_len = remaining;
1709 if (rb->base_window != NULL)
1711 /* We got the desired rep directly from the cache.
1712 This is where we need the pseudo rep_state created
1713 by build_rep_list(). */
1714 apr_size_t offset = (apr_size_t)rs->current;
1715 if (copy_len + offset > rb->base_window->len)
1716 copy_len = offset < rb->base_window->len
1717 ? rb->base_window->len - offset
1720 memcpy (cur, rb->base_window->data + offset, copy_len);
1725 if (((apr_off_t) copy_len) > rs->size - rs->current)
1726 copy_len = (apr_size_t) (rs->size - rs->current);
1728 SVN_ERR(auto_open_shared_file(rs->sfile));
1729 SVN_ERR(auto_set_start_offset(rs, rb->pool));
1731 offset = rs->start + rs->current;
1732 SVN_ERR(rs_aligned_seek(rs, NULL, offset, rb->pool));
1733 SVN_ERR(svn_io_file_read_full2(rs->sfile->rfile->file, cur,
1734 copy_len, NULL, NULL, rb->pool));
1737 rs->current += copy_len;
1739 return SVN_NO_ERROR;
1742 while (remaining > 0)
1744 /* If we have buffered data from a previous chunk, use that. */
1747 /* Determine how much to copy from the buffer. */
1748 copy_len = rb->buf_len - rb->buf_pos;
1749 if (copy_len > remaining)
1750 copy_len = remaining;
1752 /* Actually copy the data. */
1753 memcpy(cur, rb->buf + rb->buf_pos, copy_len);
1754 rb->buf_pos += copy_len;
1756 remaining -= copy_len;
1758 /* If the buffer is all used up, clear it and empty the
1760 if (rb->buf_pos == rb->buf_len)
1762 svn_pool_clear(rb->pool);
1768 svn_stringbuf_t *sbuf = NULL;
1770 rs = APR_ARRAY_IDX(rb->rs_list, 0, rep_state_t *);
1771 if (rs->current == rs->size)
1774 /* Get more buffered data by evaluating a chunk. */
1775 SVN_ERR(get_combined_window(&sbuf, rb));
1778 rb->buf_len = sbuf->len;
1779 rb->buf = sbuf->data;
1786 return SVN_NO_ERROR;
1789 /* Baton type for get_fulltext_partial. */
1790 typedef struct fulltext_baton_t
1792 /* Target buffer to write to; of at least LEN bytes. */
1795 /* Offset within the respective fulltext at which we shall start to
1796 copy data into BUFFER. */
1799 /* Number of bytes to copy. The actual amount may be less in case
1800 the fulltext is short(er). */
1803 /* Number of bytes actually copied into BUFFER. */
1807 /* Implement svn_cache__partial_getter_func_t for fulltext caches.
1808 * From the fulltext in DATA, we copy the range specified by the
1809 * fulltext_baton_t* BATON into the buffer provided by that baton.
1810 * OUT and RESULT_POOL are not used.
1812 static svn_error_t *
1813 get_fulltext_partial(void **out,
1815 apr_size_t data_len,
1817 apr_pool_t *result_pool)
1819 fulltext_baton_t *fulltext_baton = baton;
1821 /* We cached the fulltext with an NUL appended to it. */
1822 apr_size_t fulltext_len = data_len - 1;
1824 /* Clip the copy range to what the fulltext size allows. */
1825 apr_size_t start = MIN(fulltext_baton->start, fulltext_len);
1826 fulltext_baton->read = MIN(fulltext_len - start, fulltext_baton->len);
1828 /* Copy the data to the output buffer and be done. */
1829 memcpy(fulltext_baton->buffer, (const char *)data + start,
1830 fulltext_baton->read);
1832 return SVN_NO_ERROR;
1835 /* Find the fulltext specified in BATON in the fulltext cache given
1836 * as well by BATON. If that succeeds, set *CACHED to TRUE and copy
1837 * up to the next *LEN bytes into BUFFER. Set *LEN to the actual
1838 * number of bytes copied.
1840 static svn_error_t *
1841 get_contents_from_fulltext(svn_boolean_t *cached,
1842 struct rep_read_baton *baton,
1847 fulltext_baton_t fulltext_baton;
1849 SVN_ERR_ASSERT((apr_size_t)baton->fulltext_delivered
1850 == baton->fulltext_delivered);
1851 fulltext_baton.buffer = buffer;
1852 fulltext_baton.start = (apr_size_t)baton->fulltext_delivered;
1853 fulltext_baton.len = *len;
1854 fulltext_baton.read = 0;
1856 SVN_ERR(svn_cache__get_partial(&dummy, cached, baton->fulltext_cache,
1857 &baton->fulltext_cache_key,
1858 get_fulltext_partial, &fulltext_baton,
1863 baton->fulltext_delivered += fulltext_baton.read;
1864 *len = fulltext_baton.read;
1867 return SVN_NO_ERROR;
1870 /* Determine the optimal size of a string buf that shall receive a
1871 * (full-) text of NEEDED bytes.
1873 * The critical point is that those buffers may be very large and
1874 * can cause memory fragmentation. We apply simple heuristics to
1875 * make fragmentation less likely.
1878 optimimal_allocation_size(apr_size_t needed)
1880 /* For all allocations, assume some overhead that is shared between
1881 * OS memory managemnt, APR memory management and svn_stringbuf_t. */
1882 const apr_size_t overhead = 0x400;
1885 /* If an allocation size if safe for other ephemeral buffers, it should
1886 * be safe for ours. */
1887 if (needed <= SVN__STREAM_CHUNK_SIZE)
1890 /* Paranoia edge case:
1891 * Skip our heuristics if they created arithmetical overflow.
1892 * Beware to make this test work for NEEDED = APR_SIZE_MAX as well! */
1893 if (needed >= APR_SIZE_MAX / 2 - overhead)
1896 /* As per definition SVN__STREAM_CHUNK_SIZE is a power of two.
1897 * Since we know NEEDED to be larger than that, use it as the
1900 * Heuristics: Allocate a power-of-two number of bytes that fit
1901 * NEEDED plus some OVERHEAD. The APR allocator
1902 * will round it up to the next full page size.
1904 optimal = SVN__STREAM_CHUNK_SIZE;
1905 while (optimal - overhead < needed)
1908 /* This is above or equal to NEEDED. */
1909 return optimal - overhead;
1912 /* After a fulltext cache lookup failure, we will continue to read from
1913 * combined delta or plain windows. However, we must first make that data
1914 * stream in BATON catch up tho the position LEN already delivered from the
1915 * fulltext cache. Also, we need to store the reconstructed fulltext if we
1916 * want to cache it at the end.
1918 static svn_error_t *
1919 skip_contents(struct rep_read_baton *baton,
1922 svn_error_t *err = SVN_NO_ERROR;
1924 /* Do we want to cache the reconstructed fulltext? */
1925 if (SVN_IS_VALID_REVNUM(baton->fulltext_cache_key.revision))
1928 svn_filesize_t to_alloc = MAX(len, baton->len);
1930 /* This should only be happening if BATON->LEN and LEN are
1931 * cacheable, implying they fit into memory. */
1932 SVN_ERR_ASSERT((apr_size_t)to_alloc == to_alloc);
1934 /* Allocate the fulltext buffer. */
1935 baton->current_fulltext = svn_stringbuf_create_ensure(
1936 optimimal_allocation_size((apr_size_t)to_alloc),
1937 baton->filehandle_pool);
1939 /* Read LEN bytes from the window stream and store the data
1940 * in the fulltext buffer (will be filled by further reads later). */
1941 baton->current_fulltext->len = (apr_size_t)len;
1942 baton->current_fulltext->data[(apr_size_t)len] = 0;
1944 buffer = baton->current_fulltext->data;
1945 while (len > 0 && !err)
1947 apr_size_t to_read = (apr_size_t)len;
1948 err = get_contents_from_windows(baton, buffer, &to_read);
1955 /* Simply drain LEN bytes from the window stream. */
1956 apr_pool_t *subpool = subpool = svn_pool_create(baton->pool);
1957 char *buffer = apr_palloc(subpool, SVN__STREAM_CHUNK_SIZE);
1959 while (len > 0 && !err)
1961 apr_size_t to_read = len > SVN__STREAM_CHUNK_SIZE
1962 ? SVN__STREAM_CHUNK_SIZE
1965 err = get_contents_from_windows(baton, buffer, &to_read);
1969 svn_pool_destroy(subpool);
1972 return svn_error_trace(err);
1975 /* BATON is of type `rep_read_baton'; read the next *LEN bytes of the
1976 representation and store them in *BUF. Sum as we read and verify
1977 the MD5 sum at the end. */
1978 static svn_error_t *
1979 rep_read_contents(void *baton,
1983 struct rep_read_baton *rb = baton;
1985 /* Get data from the fulltext cache for as long as we can. */
1986 if (rb->fulltext_cache)
1988 svn_boolean_t cached;
1989 SVN_ERR(get_contents_from_fulltext(&cached, rb, buf, len));
1991 return SVN_NO_ERROR;
1993 /* Cache miss. From now on, we will never read from the fulltext
1994 * cache for this representation anymore. */
1995 rb->fulltext_cache = NULL;
1998 /* No fulltext cache to help us. We must read from the window stream. */
2001 /* Window stream not initialized, yet. Do it now. */
2002 SVN_ERR(build_rep_list(&rb->rs_list, &rb->base_window,
2003 &rb->src_state, &rb->len, rb->fs, &rb->rep,
2004 rb->filehandle_pool));
2006 /* In case we did read from the fulltext cache before, make the
2007 * window stream catch up. Also, initialize the fulltext buffer
2008 * if we want to cache the fulltext at the end. */
2009 SVN_ERR(skip_contents(rb, rb->fulltext_delivered));
2012 /* Get the next block of data. */
2013 SVN_ERR(get_contents_from_windows(rb, buf, len));
2015 if (rb->current_fulltext)
2016 svn_stringbuf_appendbytes(rb->current_fulltext, buf, *len);
2018 /* Perform checksumming. We want to check the checksum as soon as
2019 the last byte of data is read, in case the caller never performs
2020 a short read, but we don't want to finalize the MD5 context
2022 if (!rb->checksum_finalized)
2024 SVN_ERR(svn_checksum_update(rb->md5_checksum_ctx, buf, *len));
2026 if (rb->off == rb->len)
2028 svn_checksum_t *md5_checksum;
2029 svn_checksum_t expected;
2030 expected.kind = svn_checksum_md5;
2031 expected.digest = rb->md5_digest;
2033 rb->checksum_finalized = TRUE;
2034 SVN_ERR(svn_checksum_final(&md5_checksum, rb->md5_checksum_ctx,
2036 if (!svn_checksum_match(md5_checksum, &expected))
2037 return svn_error_create(SVN_ERR_FS_CORRUPT,
2038 svn_checksum_mismatch_err(&expected, md5_checksum,
2040 _("Checksum mismatch while reading representation")),
2045 if (rb->off == rb->len && rb->current_fulltext)
2047 fs_fs_data_t *ffd = rb->fs->fsap_data;
2048 SVN_ERR(svn_cache__set(ffd->fulltext_cache, &rb->fulltext_cache_key,
2049 rb->current_fulltext, rb->pool));
2050 rb->current_fulltext = NULL;
2053 return SVN_NO_ERROR;
2057 svn_fs_fs__get_contents(svn_stream_t **contents_p,
2059 representation_t *rep,
2060 svn_boolean_t cache_fulltext,
2065 *contents_p = svn_stream_empty(pool);
2069 fs_fs_data_t *ffd = fs->fsap_data;
2070 svn_filesize_t len = rep->expanded_size ? rep->expanded_size : rep->size;
2071 struct rep_read_baton *rb;
2073 pair_cache_key_t fulltext_cache_key = { 0 };
2074 fulltext_cache_key.revision = rep->revision;
2075 fulltext_cache_key.second = rep->item_index;
2077 /* Initialize the reader baton. Some members may added lazily
2078 * while reading from the stream */
2079 SVN_ERR(rep_read_get_baton(&rb, fs, rep, fulltext_cache_key, pool));
2081 /* Make the stream attempt fulltext cache lookups if the fulltext
2082 * is cacheable. If it is not, then also don't try to buffer and
2084 if (ffd->fulltext_cache && cache_fulltext
2085 && SVN_IS_VALID_REVNUM(rep->revision)
2086 && fulltext_size_is_cachable(ffd, len))
2088 rb->fulltext_cache = ffd->fulltext_cache;
2092 /* This will also prevent the reconstructed fulltext from being
2093 put into the cache. */
2094 rb->fulltext_cache_key.revision = SVN_INVALID_REVNUM;
2097 *contents_p = svn_stream_create(rb, pool);
2098 svn_stream_set_read2(*contents_p, NULL /* only full read support */,
2100 svn_stream_set_close(*contents_p, rep_read_contents_close);
2103 return SVN_NO_ERROR;
2106 /* Baton for cache_access_wrapper. Wraps the original parameters of
2107 * svn_fs_fs__try_process_file_content().
2109 typedef struct cache_access_wrapper_baton_t
2111 svn_fs_process_contents_func_t func;
2113 } cache_access_wrapper_baton_t;
2115 /* Wrapper to translate between svn_fs_process_contents_func_t and
2116 * svn_cache__partial_getter_func_t.
2118 static svn_error_t *
2119 cache_access_wrapper(void **out,
2121 apr_size_t data_len,
2125 cache_access_wrapper_baton_t *wrapper_baton = baton;
2127 SVN_ERR(wrapper_baton->func((const unsigned char *)data,
2128 data_len - 1, /* cache adds terminating 0 */
2129 wrapper_baton->baton,
2132 /* non-NULL value to signal the calling cache that all went well */
2135 return SVN_NO_ERROR;
2139 svn_fs_fs__try_process_file_contents(svn_boolean_t *success,
2141 node_revision_t *noderev,
2142 svn_fs_process_contents_func_t processor,
2146 representation_t *rep = noderev->data_rep;
2149 fs_fs_data_t *ffd = fs->fsap_data;
2150 pair_cache_key_t fulltext_cache_key = { 0 };
2152 fulltext_cache_key.revision = rep->revision;
2153 fulltext_cache_key.second = rep->item_index;
2154 if (ffd->fulltext_cache && SVN_IS_VALID_REVNUM(rep->revision)
2155 && fulltext_size_is_cachable(ffd, rep->expanded_size))
2157 cache_access_wrapper_baton_t wrapper_baton;
2160 wrapper_baton.func = processor;
2161 wrapper_baton.baton = baton;
2162 return svn_cache__get_partial(&dummy, success,
2163 ffd->fulltext_cache,
2164 &fulltext_cache_key,
2165 cache_access_wrapper,
2172 return SVN_NO_ERROR;
2176 /* Baton used when reading delta windows. */
2177 struct delta_read_baton
2180 unsigned char md5_digest[APR_MD5_DIGESTSIZE];
2183 /* This implements the svn_txdelta_next_window_fn_t interface. */
2184 static svn_error_t *
2185 delta_read_next_window(svn_txdelta_window_t **window, void *baton,
2188 struct delta_read_baton *drb = baton;
2189 apr_pool_t *scratch_pool = svn_pool_create(pool);
2192 if (drb->rs->current < drb->rs->size)
2194 SVN_ERR(read_delta_window(window, drb->rs->chunk_index, drb->rs, pool,
2196 drb->rs->chunk_index++;
2199 svn_pool_destroy(scratch_pool);
2201 return SVN_NO_ERROR;
2204 /* This implements the svn_txdelta_md5_digest_fn_t interface. */
2205 static const unsigned char *
2206 delta_read_md5_digest(void *baton)
2208 struct delta_read_baton *drb = baton;
2209 return drb->md5_digest;
2212 /* Return a txdelta stream for on-disk representation REP_STATE
2213 * of TARGET. Allocate the result in POOL.
2215 static svn_txdelta_stream_t *
2216 get_storaged_delta_stream(rep_state_t *rep_state,
2217 node_revision_t *target,
2220 /* Create the delta read baton. */
2221 struct delta_read_baton *drb = apr_pcalloc(pool, sizeof(*drb));
2222 drb->rs = rep_state;
2223 memcpy(drb->md5_digest, target->data_rep->md5_digest,
2224 sizeof(drb->md5_digest));
2225 return svn_txdelta_stream_create(drb, delta_read_next_window,
2226 delta_read_md5_digest, pool);
2230 svn_fs_fs__get_file_delta_stream(svn_txdelta_stream_t **stream_p,
2232 node_revision_t *source,
2233 node_revision_t *target,
2236 svn_stream_t *source_stream, *target_stream;
2237 rep_state_t *rep_state;
2238 svn_fs_fs__rep_header_t *rep_header;
2239 fs_fs_data_t *ffd = fs->fsap_data;
2241 /* Try a shortcut: if the target is stored as a delta against the source,
2242 then just use that delta. However, prefer using the fulltext cache
2243 whenever that is available. */
2244 if (target->data_rep && (source || ! ffd->fulltext_cache))
2246 /* Read target's base rep if any. */
2247 SVN_ERR(create_rep_state(&rep_state, &rep_header, NULL,
2248 target->data_rep, fs, pool, pool));
2250 if (source && source->data_rep && target->data_rep)
2252 /* If that matches source, then use this delta as is.
2253 Note that we want an actual delta here. E.g. a self-delta would
2254 not be good enough. */
2255 if (rep_header->type == svn_fs_fs__rep_delta
2256 && rep_header->base_revision == source->data_rep->revision
2257 && rep_header->base_item_index == source->data_rep->item_index)
2259 *stream_p = get_storaged_delta_stream(rep_state, target, pool);
2260 return SVN_NO_ERROR;
2265 /* We want a self-delta. There is a fair chance that TARGET got
2266 added in this revision and is already stored in the requested
2268 if (rep_header->type == svn_fs_fs__rep_self_delta)
2270 *stream_p = get_storaged_delta_stream(rep_state, target, pool);
2271 return SVN_NO_ERROR;
2275 /* Don't keep file handles open for longer than necessary. */
2276 if (rep_state->sfile->rfile)
2278 SVN_ERR(svn_fs_fs__close_revision_file(rep_state->sfile->rfile));
2279 rep_state->sfile->rfile = NULL;
2283 /* Read both fulltexts and construct a delta. */
2285 SVN_ERR(svn_fs_fs__get_contents(&source_stream, fs, source->data_rep,
2288 source_stream = svn_stream_empty(pool);
2289 SVN_ERR(svn_fs_fs__get_contents(&target_stream, fs, target->data_rep,
2292 /* Because source and target stream will already verify their content,
2293 * there is no need to do this once more. In particular if the stream
2294 * content is being fetched from cache. */
2295 svn_txdelta2(stream_p, source_stream, target_stream, FALSE, pool);
2297 return SVN_NO_ERROR;
2300 /* Return TRUE when all svn_fs_dirent_t* in ENTRIES are already sorted
2301 by their respective name. */
2302 static svn_boolean_t
2303 sorted(apr_array_header_t *entries)
2307 const svn_fs_dirent_t * const *dirents = (const void *)entries->elts;
2308 for (i = 0; i < entries->nelts-1; ++i)
2309 if (strcmp(dirents[i]->name, dirents[i+1]->name) > 0)
2315 /* Compare the names of the two dirents given in **A and **B. */
2317 compare_dirents(const void *a, const void *b)
2319 const svn_fs_dirent_t *lhs = *((const svn_fs_dirent_t * const *) a);
2320 const svn_fs_dirent_t *rhs = *((const svn_fs_dirent_t * const *) b);
2322 return strcmp(lhs->name, rhs->name);
2325 /* Compare the name of the dirents given in **A with the C string in *B. */
2327 compare_dirent_name(const void *a, const void *b)
2329 const svn_fs_dirent_t *lhs = *((const svn_fs_dirent_t * const *) a);
2330 const char *rhs = b;
2332 return strcmp(lhs->name, rhs);
2335 /* Into ENTRIES, read all directories entries from the key-value text in
2336 * STREAM. If INCREMENTAL is TRUE, read until the end of the STREAM and
2337 * update the data. ID is provided for nicer error messages.
2339 static svn_error_t *
2340 read_dir_entries(apr_array_header_t *entries,
2341 svn_stream_t *stream,
2342 svn_boolean_t incremental,
2343 const svn_fs_id_t *id,
2344 apr_pool_t *result_pool,
2345 apr_pool_t *scratch_pool)
2347 apr_pool_t *iterpool = svn_pool_create(scratch_pool);
2348 apr_hash_t *hash = incremental ? svn_hash__make(scratch_pool) : NULL;
2349 const char *terminator = SVN_HASH_TERMINATOR;
2351 /* Read until the terminator (non-incremental) or the end of STREAM
2352 (incremental mode). In the latter mode, we use a temporary HASH
2353 to make updating and removing entries cheaper. */
2356 svn_hash__entry_t entry;
2357 svn_fs_dirent_t *dirent;
2360 svn_pool_clear(iterpool);
2361 SVN_ERR(svn_hash__read_entry(&entry, stream, terminator,
2362 incremental, iterpool));
2364 /* End of directory? */
2365 if (entry.key == NULL)
2367 /* In incremental mode, we skip the terminator and read the
2368 increments following it until the end of the stream. */
2369 if (incremental && terminator)
2375 /* Deleted entry? */
2376 if (entry.val == NULL)
2378 /* We must be in incremental mode */
2380 apr_hash_set(hash, entry.key, entry.keylen, NULL);
2384 /* Add a new directory entry. */
2385 dirent = apr_pcalloc(result_pool, sizeof(*dirent));
2386 dirent->name = apr_pstrmemdup(result_pool, entry.key, entry.keylen);
2388 str = svn_cstring_tokenize(" ", &entry.val);
2390 return svn_error_createf(SVN_ERR_FS_CORRUPT, NULL,
2391 _("Directory entry corrupt in '%s'"),
2392 svn_fs_fs__id_unparse(id, scratch_pool)->data);
2394 if (strcmp(str, SVN_FS_FS__KIND_FILE) == 0)
2396 dirent->kind = svn_node_file;
2398 else if (strcmp(str, SVN_FS_FS__KIND_DIR) == 0)
2400 dirent->kind = svn_node_dir;
2404 return svn_error_createf(SVN_ERR_FS_CORRUPT, NULL,
2405 _("Directory entry corrupt in '%s'"),
2406 svn_fs_fs__id_unparse(id, scratch_pool)->data);
2409 str = svn_cstring_tokenize(" ", &entry.val);
2411 return svn_error_createf(SVN_ERR_FS_CORRUPT, NULL,
2412 _("Directory entry corrupt in '%s'"),
2413 svn_fs_fs__id_unparse(id, scratch_pool)->data);
2415 SVN_ERR(svn_fs_fs__id_parse(&dirent->id, str, result_pool));
2417 /* In incremental mode, update the hash; otherwise, write to the
2418 * final array. Be sure to use hash keys that survive this iteration.
2421 apr_hash_set(hash, dirent->name, entry.keylen, dirent);
2423 APR_ARRAY_PUSH(entries, svn_fs_dirent_t *) = dirent;
2426 /* Convert container to a sorted array. */
2429 apr_hash_index_t *hi;
2430 for (hi = apr_hash_first(iterpool, hash); hi; hi = apr_hash_next(hi))
2431 APR_ARRAY_PUSH(entries, svn_fs_dirent_t *) = apr_hash_this_val(hi);
2434 if (!sorted(entries))
2435 svn_sort__array(entries, compare_dirents);
2437 svn_pool_destroy(iterpool);
2439 return SVN_NO_ERROR;
2442 /* Fetch the contents of a directory into ENTRIES. Values are stored
2443 as filename to string mappings; further conversion is necessary to
2444 convert them into svn_fs_dirent_t values. */
2445 static svn_error_t *
2446 get_dir_contents(apr_array_header_t **entries,
2448 node_revision_t *noderev,
2449 apr_pool_t *result_pool,
2450 apr_pool_t *scratch_pool)
2452 svn_stream_t *contents;
2454 *entries = apr_array_make(result_pool, 16, sizeof(svn_fs_dirent_t *));
2455 if (noderev->data_rep && svn_fs_fs__id_txn_used(&noderev->data_rep->txn_id))
2457 const char *filename
2458 = svn_fs_fs__path_txn_node_children(fs, noderev->id, scratch_pool);
2460 /* The representation is mutable. Read the old directory
2461 contents from the mutable children file, followed by the
2462 changes we've made in this transaction. */
2463 SVN_ERR(svn_stream_open_readonly(&contents, filename, scratch_pool,
2465 SVN_ERR(read_dir_entries(*entries, contents, TRUE, noderev->id,
2466 result_pool, scratch_pool));
2467 SVN_ERR(svn_stream_close(contents));
2469 else if (noderev->data_rep)
2471 /* Undeltify content before parsing it. Otherwise, we could only
2472 * parse it byte-by-byte.
2474 apr_size_t len = noderev->data_rep->expanded_size
2475 ? (apr_size_t)noderev->data_rep->expanded_size
2476 : (apr_size_t)noderev->data_rep->size;
2477 svn_stringbuf_t *text;
2479 /* The representation is immutable. Read it normally. */
2480 SVN_ERR(svn_fs_fs__get_contents(&contents, fs, noderev->data_rep,
2481 FALSE, scratch_pool));
2482 SVN_ERR(svn_stringbuf_from_stream(&text, contents, len, scratch_pool));
2483 SVN_ERR(svn_stream_close(contents));
2485 /* de-serialize hash */
2486 contents = svn_stream_from_stringbuf(text, scratch_pool);
2487 SVN_ERR(read_dir_entries(*entries, contents, FALSE, noderev->id,
2488 result_pool, scratch_pool));
2491 return SVN_NO_ERROR;
2495 /* Return the cache object in FS responsible to storing the directory the
2496 * NODEREV plus the corresponding *KEY. If no cache exists, return NULL.
2497 * PAIR_KEY must point to some key struct, which does not need to be
2498 * initialized. We use it to avoid dynamic allocation.
2500 static svn_cache__t *
2501 locate_dir_cache(svn_fs_t *fs,
2503 pair_cache_key_t *pair_key,
2504 node_revision_t *noderev,
2507 fs_fs_data_t *ffd = fs->fsap_data;
2508 if (svn_fs_fs__id_is_txn(noderev->id))
2510 /* data in txns requires the expensive fs_id-based addressing mode */
2511 *key = svn_fs_fs__id_unparse(noderev->id, pool)->data;
2512 return ffd->txn_dir_cache;
2516 /* committed data can use simple rev,item pairs */
2517 if (noderev->data_rep)
2519 pair_key->revision = noderev->data_rep->revision;
2520 pair_key->second = noderev->data_rep->item_index;
2525 /* no data rep -> empty directory.
2526 A NULL key causes a cache miss. */
2530 return ffd->dir_cache;
2535 svn_fs_fs__rep_contents_dir(apr_array_header_t **entries_p,
2537 node_revision_t *noderev,
2538 apr_pool_t *result_pool,
2539 apr_pool_t *scratch_pool)
2541 pair_cache_key_t pair_key = { 0 };
2544 /* find the cache we may use */
2545 svn_cache__t *cache = locate_dir_cache(fs, &key, &pair_key, noderev,
2549 svn_boolean_t found;
2551 SVN_ERR(svn_cache__get((void **)entries_p, &found, cache, key,
2554 return SVN_NO_ERROR;
2557 /* Read in the directory contents. */
2558 SVN_ERR(get_dir_contents(entries_p, fs, noderev, result_pool,
2561 /* Update the cache, if we are to use one. */
2563 SVN_ERR(svn_cache__set(cache, key, *entries_p, scratch_pool));
2565 return SVN_NO_ERROR;
2569 svn_fs_fs__find_dir_entry(apr_array_header_t *entries,
2573 svn_fs_dirent_t **result
2574 = svn_sort__array_lookup(entries, name, hint, compare_dirent_name);
2575 return result ? *result : NULL;
2579 svn_fs_fs__rep_contents_dir_entry(svn_fs_dirent_t **dirent,
2581 node_revision_t *noderev,
2583 apr_pool_t *result_pool,
2584 apr_pool_t *scratch_pool)
2586 svn_boolean_t found = FALSE;
2588 /* find the cache we may use */
2589 pair_cache_key_t pair_key = { 0 };
2591 svn_cache__t *cache = locate_dir_cache(fs, &key, &pair_key, noderev,
2596 SVN_ERR(svn_cache__get_partial((void **)dirent,
2600 svn_fs_fs__extract_dir_entry,
2605 /* fetch data from disk if we did not find it in the cache */
2608 apr_array_header_t *entries;
2609 svn_fs_dirent_t *entry;
2610 svn_fs_dirent_t *entry_copy = NULL;
2612 /* read the dir from the file system. It will probably be put it
2613 into the cache for faster lookup in future calls. */
2614 SVN_ERR(svn_fs_fs__rep_contents_dir(&entries, fs, noderev,
2615 scratch_pool, scratch_pool));
2617 /* find desired entry and return a copy in POOL, if found */
2618 entry = svn_fs_fs__find_dir_entry(entries, name, NULL);
2621 entry_copy = apr_palloc(result_pool, sizeof(*entry_copy));
2622 entry_copy->name = apr_pstrdup(result_pool, entry->name);
2623 entry_copy->id = svn_fs_fs__id_copy(entry->id, result_pool);
2624 entry_copy->kind = entry->kind;
2627 *dirent = entry_copy;
2630 return SVN_NO_ERROR;
2634 svn_fs_fs__get_proplist(apr_hash_t **proplist_p,
2636 node_revision_t *noderev,
2639 apr_hash_t *proplist;
2640 svn_stream_t *stream;
2642 if (noderev->prop_rep && svn_fs_fs__id_txn_used(&noderev->prop_rep->txn_id))
2645 const char *filename
2646 = svn_fs_fs__path_txn_node_props(fs, noderev->id, pool);
2647 proplist = apr_hash_make(pool);
2649 SVN_ERR(svn_stream_open_readonly(&stream, filename, pool, pool));
2650 err = svn_hash_read2(proplist, stream, SVN_HASH_TERMINATOR, pool);
2653 svn_string_t *id_str = svn_fs_fs__id_unparse(noderev->id, pool);
2655 svn_error_clear(svn_stream_close(stream));
2656 return svn_error_quick_wrapf(err,
2657 _("malformed property list for node-revision '%s' in '%s'"),
2658 id_str->data, filename);
2660 SVN_ERR(svn_stream_close(stream));
2662 else if (noderev->prop_rep)
2665 fs_fs_data_t *ffd = fs->fsap_data;
2666 representation_t *rep = noderev->prop_rep;
2667 pair_cache_key_t key = { 0 };
2669 key.revision = rep->revision;
2670 key.second = rep->item_index;
2671 if (ffd->properties_cache && SVN_IS_VALID_REVNUM(rep->revision))
2673 svn_boolean_t is_cached;
2674 SVN_ERR(svn_cache__get((void **) proplist_p, &is_cached,
2675 ffd->properties_cache, &key, pool));
2677 return SVN_NO_ERROR;
2680 proplist = apr_hash_make(pool);
2681 SVN_ERR(svn_fs_fs__get_contents(&stream, fs, noderev->prop_rep, FALSE,
2683 err = svn_hash_read2(proplist, stream, SVN_HASH_TERMINATOR, pool);
2686 svn_string_t *id_str = svn_fs_fs__id_unparse(noderev->id, pool);
2688 svn_error_clear(svn_stream_close(stream));
2689 return svn_error_quick_wrapf(err,
2690 _("malformed property list for node-revision '%s'"),
2693 SVN_ERR(svn_stream_close(stream));
2695 if (ffd->properties_cache && SVN_IS_VALID_REVNUM(rep->revision))
2696 SVN_ERR(svn_cache__set(ffd->properties_cache, &key, proplist, pool));
2700 /* return an empty prop list if the node doesn't have any props */
2701 proplist = apr_hash_make(pool);
2704 *proplist_p = proplist;
2706 return SVN_NO_ERROR;
2710 svn_fs_fs__get_changes(apr_array_header_t **changes,
2713 apr_pool_t *result_pool)
2715 apr_off_t changes_offset = SVN_FS_FS__ITEM_INDEX_CHANGES;
2716 svn_fs_fs__revision_file_t *revision_file;
2717 svn_boolean_t found;
2718 fs_fs_data_t *ffd = fs->fsap_data;
2719 apr_pool_t *scratch_pool = svn_pool_create(result_pool);
2721 /* try cache lookup first */
2723 if (ffd->changes_cache)
2725 SVN_ERR(svn_cache__get((void **) changes, &found, ffd->changes_cache,
2726 &rev, result_pool));
2735 /* read changes from revision file */
2737 SVN_ERR(svn_fs_fs__ensure_revision_exists(rev, fs, scratch_pool));
2738 SVN_ERR(svn_fs_fs__open_pack_or_rev_file(&revision_file, fs, rev,
2739 scratch_pool, scratch_pool));
2741 if (use_block_read(fs))
2743 /* 'block-read' will also provide us with the desired data */
2744 SVN_ERR(block_read((void **)changes, fs,
2745 rev, SVN_FS_FS__ITEM_INDEX_CHANGES,
2746 revision_file, result_pool, scratch_pool));
2750 /* Addressing is very different for old formats
2751 * (needs to read the revision trailer). */
2752 if (svn_fs_fs__use_log_addressing(fs))
2753 SVN_ERR(svn_fs_fs__item_offset(&changes_offset, fs,
2754 revision_file, rev, NULL,
2755 SVN_FS_FS__ITEM_INDEX_CHANGES,
2758 SVN_ERR(get_root_changes_offset(NULL, &changes_offset,
2759 revision_file, fs, rev,
2762 /* Actual reading and parsing are the same, though. */
2763 SVN_ERR(aligned_seek(fs, revision_file->file, NULL, changes_offset,
2765 SVN_ERR(svn_fs_fs__read_changes(changes, revision_file->stream,
2766 result_pool, scratch_pool));
2768 /* cache for future reference */
2770 if (ffd->changes_cache)
2772 /* Guesstimate for the size of the in-cache representation. */
2773 apr_size_t estimated_size = (apr_size_t)250 * (*changes)->nelts;
2775 /* Don't even serialize data that probably won't fit into the
2776 * cache. This often implies that either CHANGES is very
2777 * large, memory is scarce or both. Having a huge temporary
2778 * copy would not be a good thing in either case. */
2779 if (svn_cache__is_cachable(ffd->changes_cache, estimated_size))
2780 SVN_ERR(svn_cache__set(ffd->changes_cache, &rev, *changes,
2785 SVN_ERR(svn_fs_fs__close_revision_file(revision_file));
2788 SVN_ERR(dbg_log_access(fs, rev, changes_offset, *changes,
2789 SVN_FS_FS__ITEM_TYPE_CHANGES, scratch_pool));
2791 svn_pool_destroy(scratch_pool);
2792 return SVN_NO_ERROR;
2795 /* Inialize the representation read state RS for the given REP_HEADER and
2796 * p2l index ENTRY. If not NULL, assign FILE and STREAM to RS.
2797 * Use RESULT_POOL for allocations.
2799 static svn_error_t *
2800 init_rep_state(rep_state_t *rs,
2801 svn_fs_fs__rep_header_t *rep_header,
2803 svn_fs_fs__revision_file_t *file,
2804 svn_fs_fs__p2l_entry_t* entry,
2805 apr_pool_t *result_pool)
2807 fs_fs_data_t *ffd = fs->fsap_data;
2808 shared_file_t *shared_file = apr_pcalloc(result_pool, sizeof(*shared_file));
2810 /* this function does not apply to representation containers */
2811 SVN_ERR_ASSERT(entry->type >= SVN_FS_FS__ITEM_TYPE_FILE_REP
2812 && entry->type <= SVN_FS_FS__ITEM_TYPE_DIR_PROPS);
2814 shared_file->rfile = file;
2815 shared_file->fs = fs;
2816 shared_file->revision = entry->item.revision;
2817 shared_file->pool = result_pool;
2819 rs->sfile = shared_file;
2820 rs->revision = entry->item.revision;
2821 rs->item_index = entry->item.number;
2822 rs->header_size = rep_header->header_size;
2823 rs->start = entry->offset + rs->header_size;
2824 rs->current = rep_header->type == svn_fs_fs__rep_plain ? 0 : 4;
2825 rs->size = entry->size - rep_header->header_size - 7;
2827 rs->chunk_index = 0;
2828 rs->raw_window_cache = ffd->raw_window_cache;
2829 rs->window_cache = ffd->txdelta_window_cache;
2830 rs->combined_cache = ffd->combined_window_cache;
2832 return SVN_NO_ERROR;
2835 /* Implement svn_cache__partial_getter_func_t for txdelta windows.
2836 * Instead of the whole window data, return only END_OFFSET member.
2838 static svn_error_t *
2839 get_txdelta_window_end(void **out,
2841 apr_size_t data_len,
2843 apr_pool_t *result_pool)
2845 const svn_fs_fs__txdelta_cached_window_t *window
2846 = (const svn_fs_fs__txdelta_cached_window_t *)data;
2847 *(apr_off_t*)out = window->end_offset;
2849 return SVN_NO_ERROR;
2852 /* Implement svn_cache__partial_getter_func_t for raw windows.
2853 * Instead of the whole window data, return only END_OFFSET member.
2855 static svn_error_t *
2856 get_raw_window_end(void **out,
2858 apr_size_t data_len,
2860 apr_pool_t *result_pool)
2862 const svn_fs_fs__raw_cached_window_t *window
2863 = (const svn_fs_fs__raw_cached_window_t *)data;
2864 *(apr_off_t*)out = window->end_offset;
2866 return SVN_NO_ERROR;
2869 /* Walk through all windows in the representation addressed by RS in FS
2870 * (excluding the delta bases) and put those not already cached into the
2871 * window caches. If MAX_OFFSET is not -1, don't read windows that start
2872 * at or beyond that offset. Use POOL for temporary allocations.
2874 * This function requires RS->RAW_WINDOW_CACHE and RS->WINDOW_CACHE to
2877 static svn_error_t *
2878 cache_windows(svn_fs_t *fs,
2880 apr_off_t max_offset,
2883 apr_pool_t *iterpool = svn_pool_create(pool);
2884 while (rs->current < rs->size)
2886 apr_off_t end_offset;
2887 svn_boolean_t found = FALSE;
2888 window_cache_key_t key = { 0 };
2890 svn_pool_clear(iterpool);
2892 if (max_offset != -1 && rs->start + rs->current >= max_offset)
2894 svn_pool_destroy(iterpool);
2895 return SVN_NO_ERROR;
2898 /* We don't need to read the data again if it is already in cache.
2899 * It might be cached as either raw or parsed window.
2901 SVN_ERR(svn_cache__get_partial((void **) &end_offset, &found,
2902 rs->raw_window_cache,
2903 get_window_key(&key, rs),
2904 get_raw_window_end, NULL,
2907 SVN_ERR(svn_cache__get_partial((void **) &end_offset, &found,
2908 rs->window_cache, &key,
2909 get_txdelta_window_end, NULL,
2914 rs->current = end_offset;
2918 /* Read, decode and cache the window. */
2919 svn_fs_fs__raw_cached_window_t window;
2920 apr_off_t start_offset = rs->start + rs->current;
2921 apr_size_t window_len;
2924 /* navigate to the current window */
2925 SVN_ERR(rs_aligned_seek(rs, NULL, start_offset, iterpool));
2926 SVN_ERR(svn_txdelta__read_raw_window_len(&window_len,
2927 rs->sfile->rfile->stream,
2930 /* Read the raw window. */
2931 buf = apr_palloc(iterpool, window_len + 1);
2932 SVN_ERR(rs_aligned_seek(rs, NULL, start_offset, iterpool));
2933 SVN_ERR(svn_io_file_read_full2(rs->sfile->rfile->file, buf,
2934 window_len, NULL, NULL, iterpool));
2935 buf[window_len] = 0;
2937 /* update relative offset in representation */
2938 rs->current += window_len;
2940 /* Construct the cachable raw window object. */
2941 window.end_offset = rs->current;
2942 window.window.len = window_len;
2943 window.window.data = buf;
2945 /* cache the window now */
2946 SVN_ERR(svn_cache__set(rs->raw_window_cache, &key, &window,
2950 if (rs->current > rs->size)
2951 return svn_error_create(SVN_ERR_FS_CORRUPT, NULL,
2952 _("Reading one svndiff window read beyond "
2953 "the end of the representation"));
2958 svn_pool_destroy(iterpool);
2959 return SVN_NO_ERROR;
2962 /* Read all txdelta / plain windows following REP_HEADER in FS as described
2963 * by ENTRY. Read the data from the already open FILE and the wrapping
2964 * STREAM object. If MAX_OFFSET is not -1, don't read windows that start
2965 * at or beyond that offset. Use SCRATCH_POOL for temporary allocations.
2966 * If caching is not enabled, this is a no-op.
2968 static svn_error_t *
2969 block_read_windows(svn_fs_fs__rep_header_t *rep_header,
2971 svn_fs_fs__revision_file_t *rev_file,
2972 svn_fs_fs__p2l_entry_t* entry,
2973 apr_off_t max_offset,
2974 apr_pool_t *result_pool,
2975 apr_pool_t *scratch_pool)
2977 fs_fs_data_t *ffd = fs->fsap_data;
2978 rep_state_t rs = { 0 };
2980 window_cache_key_t key = { 0 };
2982 if ( (rep_header->type != svn_fs_fs__rep_plain
2983 && (!ffd->txdelta_window_cache || !ffd->raw_window_cache))
2984 || (rep_header->type == svn_fs_fs__rep_plain
2985 && !ffd->combined_window_cache))
2986 return SVN_NO_ERROR;
2988 SVN_ERR(init_rep_state(&rs, rep_header, fs, rev_file, entry,
2991 /* RS->FILE may be shared between RS instances -> make sure we point
2992 * to the right data. */
2993 offset = rs.start + rs.current;
2994 if (rep_header->type == svn_fs_fs__rep_plain)
2996 svn_stringbuf_t *plaintext;
2997 svn_boolean_t is_cached;
2999 /* already in cache? */
3000 SVN_ERR(svn_cache__has_key(&is_cached, rs.combined_cache,
3001 get_window_key(&key, &rs),
3004 return SVN_NO_ERROR;
3006 /* for larger reps, the header may have crossed a block boundary.
3007 * make sure we still read blocks properly aligned, i.e. don't use
3008 * plain seek here. */
3009 SVN_ERR(aligned_seek(fs, rev_file->file, NULL, offset, scratch_pool));
3011 plaintext = svn_stringbuf_create_ensure(rs.size, result_pool);
3012 SVN_ERR(svn_io_file_read_full2(rev_file->file, plaintext->data,
3013 rs.size, &plaintext->len, NULL,
3015 plaintext->data[plaintext->len] = 0;
3016 rs.current += rs.size;
3018 SVN_ERR(set_cached_combined_window(plaintext, &rs, scratch_pool));
3022 SVN_ERR(cache_windows(fs, &rs, max_offset, scratch_pool));
3025 return SVN_NO_ERROR;
3028 /* Try to get the representation header identified by KEY from FS's cache.
3029 * If it has not been cached, read it from the current position in STREAM
3030 * and put it into the cache (if caching has been enabled for rep headers).
3031 * Return the result in *REP_HEADER. Use POOL for allocations.
3033 static svn_error_t *
3034 read_rep_header(svn_fs_fs__rep_header_t **rep_header,
3036 svn_stream_t *stream,
3037 pair_cache_key_t *key,
3038 apr_pool_t *result_pool,
3039 apr_pool_t *scratch_pool)
3041 fs_fs_data_t *ffd = fs->fsap_data;
3042 svn_boolean_t is_cached = FALSE;
3044 if (ffd->rep_header_cache)
3046 SVN_ERR(svn_cache__get((void**)rep_header, &is_cached,
3047 ffd->rep_header_cache, key,
3050 return SVN_NO_ERROR;
3053 SVN_ERR(svn_fs_fs__read_rep_header(rep_header, stream, result_pool,
3056 if (ffd->rep_header_cache)
3057 SVN_ERR(svn_cache__set(ffd->rep_header_cache, key, *rep_header,
3060 return SVN_NO_ERROR;
3063 /* Fetch the representation data (header, txdelta / plain windows)
3064 * addressed by ENTRY->ITEM in FS and cache it if caches are enabled.
3065 * Read the data from the already open FILE and the wrapping
3066 * STREAM object. If MAX_OFFSET is not -1, don't read windows that start
3067 * at or beyond that offset.
3068 * Use SCRATCH_POOL for temporary allocations.
3070 static svn_error_t *
3071 block_read_contents(svn_fs_t *fs,
3072 svn_fs_fs__revision_file_t *rev_file,
3073 svn_fs_fs__p2l_entry_t* entry,
3074 apr_off_t max_offset,
3075 apr_pool_t *result_pool,
3076 apr_pool_t *scratch_pool)
3078 pair_cache_key_t header_key = { 0 };
3079 svn_fs_fs__rep_header_t *rep_header;
3081 header_key.revision = (apr_int32_t)entry->item.revision;
3082 header_key.second = entry->item.number;
3084 SVN_ERR(read_rep_header(&rep_header, fs, rev_file->stream, &header_key,
3085 result_pool, scratch_pool));
3086 SVN_ERR(block_read_windows(rep_header, fs, rev_file, entry, max_offset,
3087 result_pool, scratch_pool));
3089 return SVN_NO_ERROR;
3092 /* For the given REV_FILE in FS, in *STREAM return a stream covering the
3093 * item specified by ENTRY. Also, verify the item's content by low-level
3094 * checksum. Allocate the result in POOL.
3096 static svn_error_t *
3097 read_item(svn_stream_t **stream,
3099 svn_fs_fs__revision_file_t *rev_file,
3100 svn_fs_fs__p2l_entry_t* entry,
3103 apr_uint32_t digest;
3104 svn_checksum_t *expected, *actual;
3105 apr_uint32_t plain_digest;
3107 /* Read item into string buffer. */
3108 svn_stringbuf_t *text = svn_stringbuf_create_ensure(entry->size, pool);
3109 text->len = entry->size;
3110 text->data[text->len] = 0;
3111 SVN_ERR(svn_io_file_read_full2(rev_file->file, text->data, text->len,
3114 /* Return (construct, calculate) stream and checksum. */
3115 *stream = svn_stream_from_stringbuf(text, pool);
3116 digest = svn__fnv1a_32x4(text->data, text->len);
3118 /* Checksums will match most of the time. */
3119 if (entry->fnv1_checksum == digest)
3120 return SVN_NO_ERROR;
3122 /* Construct proper checksum objects from their digests to allow for
3123 * nice error messages. */
3124 plain_digest = htonl(entry->fnv1_checksum);
3125 expected = svn_checksum__from_digest_fnv1a_32x4(
3126 (const unsigned char *)&plain_digest, pool);
3127 plain_digest = htonl(digest);
3128 actual = svn_checksum__from_digest_fnv1a_32x4(
3129 (const unsigned char *)&plain_digest, pool);
3131 /* Construct the full error message with all the info we have. */
3132 return svn_checksum_mismatch_err(expected, actual, pool,
3133 _("Low-level checksum mismatch while reading\n"
3134 "%s bytes of meta data at offset %s "
3135 "for item %s in revision %ld"),
3136 apr_psprintf(pool, "%" APR_OFF_T_FMT, entry->size),
3137 apr_psprintf(pool, "%" APR_OFF_T_FMT, entry->offset),
3138 apr_psprintf(pool, "%" APR_UINT64_T_FMT, entry->item.number),
3139 entry->item.revision);
3142 /* If not already cached or if MUST_READ is set, read the changed paths
3143 * list addressed by ENTRY in FS and retúrn it in *CHANGES. Cache the
3144 * result if caching is enabled. Read the data from the already open
3145 * FILE and wrapping FILE_STREAM. Use POOL for allocations.
3147 static svn_error_t *
3148 block_read_changes(apr_array_header_t **changes,
3150 svn_fs_fs__revision_file_t *rev_file,
3151 svn_fs_fs__p2l_entry_t *entry,
3152 svn_boolean_t must_read,
3153 apr_pool_t *result_pool,
3154 apr_pool_t *scratch_pool)
3156 fs_fs_data_t *ffd = fs->fsap_data;
3157 svn_stream_t *stream;
3158 if (!must_read && !ffd->changes_cache)
3159 return SVN_NO_ERROR;
3161 /* already in cache? */
3162 if (!must_read && ffd->changes_cache)
3164 svn_boolean_t is_cached;
3165 SVN_ERR(svn_cache__has_key(&is_cached, ffd->changes_cache,
3166 &entry->item.revision,
3169 return SVN_NO_ERROR;
3172 SVN_ERR(read_item(&stream, fs, rev_file, entry, scratch_pool));
3174 /* read changes from revision file */
3175 SVN_ERR(svn_fs_fs__read_changes(changes, stream, result_pool,
3178 /* cache for future reference */
3179 if (ffd->changes_cache)
3180 SVN_ERR(svn_cache__set(ffd->changes_cache, &entry->item.revision,
3181 *changes, scratch_pool));
3183 return SVN_NO_ERROR;
3186 /* If not already cached or if MUST_READ is set, read the nod revision
3187 * addressed by ENTRY in FS and retúrn it in *NODEREV_P. Cache the
3188 * result if caching is enabled. Read the data from the already open
3189 * FILE and wrapping FILE_STREAM. Use SCRATCH_POOL for temporary allocations.
3191 static svn_error_t *
3192 block_read_noderev(node_revision_t **noderev_p,
3194 svn_fs_fs__revision_file_t *rev_file,
3195 svn_fs_fs__p2l_entry_t *entry,
3196 svn_boolean_t must_read,
3197 apr_pool_t *result_pool,
3198 apr_pool_t *scratch_pool)
3200 fs_fs_data_t *ffd = fs->fsap_data;
3201 svn_stream_t *stream;
3203 pair_cache_key_t key = { 0 };
3204 key.revision = entry->item.revision;
3205 key.second = entry->item.number;
3207 if (!must_read && !ffd->node_revision_cache)
3208 return SVN_NO_ERROR;
3210 /* already in cache? */
3211 if (!must_read && ffd->node_revision_cache)
3213 svn_boolean_t is_cached;
3214 SVN_ERR(svn_cache__has_key(&is_cached, ffd->node_revision_cache,
3215 &key, scratch_pool));
3217 return SVN_NO_ERROR;
3220 SVN_ERR(read_item(&stream, fs, rev_file, entry, scratch_pool));
3222 /* read node rev from revision file */
3223 SVN_ERR(svn_fs_fs__read_noderev(noderev_p, stream,
3224 result_pool, scratch_pool));
3226 /* Workaround issue #4031: is-fresh-txn-root in revision files. */
3227 (*noderev_p)->is_fresh_txn_root = FALSE;
3229 if (ffd->node_revision_cache)
3230 SVN_ERR(svn_cache__set(ffd->node_revision_cache, &key, *noderev_p,
3233 return SVN_NO_ERROR;
3236 /* Read the whole (e.g. 64kB) block containing ITEM_INDEX of REVISION in FS
3237 * and put all data into cache. If necessary and depending on heuristics,
3238 * neighboring blocks may also get read. The data is being read from
3239 * already open REVISION_FILE, which must be the correct rev / pack file
3242 * For noderevs and changed path lists, the item fetched can be allocated
3243 * RESULT_POOL and returned in *RESULT. Otherwise, RESULT must be NULL.
3245 static svn_error_t *
3246 block_read(void **result,
3248 svn_revnum_t revision,
3249 apr_uint64_t item_index,
3250 svn_fs_fs__revision_file_t *revision_file,
3251 apr_pool_t *result_pool,
3252 apr_pool_t *scratch_pool)
3254 fs_fs_data_t *ffd = fs->fsap_data;
3255 apr_off_t offset, wanted_offset = 0;
3256 apr_off_t block_start = 0;
3257 apr_array_header_t *entries;
3260 apr_pool_t *iterpool;
3262 /* Block read is an optional feature. If the caller does not want anything
3263 * specific we may not have to read anything. */
3265 return SVN_NO_ERROR;
3267 iterpool = svn_pool_create(scratch_pool);
3269 /* don't try this on transaction protorev files */
3270 SVN_ERR_ASSERT(SVN_IS_VALID_REVNUM(revision));
3272 /* index lookup: find the OFFSET of the item we *must* read plus (in the
3273 * "do-while" block) the list of items in the same block. */
3274 SVN_ERR(svn_fs_fs__item_offset(&wanted_offset, fs, revision_file,
3275 revision, NULL, item_index, iterpool));
3277 offset = wanted_offset;
3281 * Read this block. If the last item crosses the block boundary, read
3282 * the next block but stop there. Because cross-boundary items cause
3283 * blocks to be read twice, this heuristics will limit this effect to
3284 * approx. 50% of blocks, probably less, while providing a sensible
3285 * amount of read-ahead.
3289 /* fetch list of items in the block surrounding OFFSET */
3290 block_start = offset - (offset % ffd->block_size);
3291 SVN_ERR(svn_fs_fs__p2l_index_lookup(&entries, fs, revision_file,
3292 revision, block_start,
3293 ffd->block_size, scratch_pool,
3296 SVN_ERR(aligned_seek(fs, revision_file->file, &block_start, offset,
3299 /* read all items from the block */
3300 for (i = 0; i < entries->nelts; ++i)
3302 svn_boolean_t is_result, is_wanted;
3304 svn_fs_fs__p2l_entry_t* entry;
3306 svn_pool_clear(iterpool);
3308 /* skip empty sections */
3309 entry = &APR_ARRAY_IDX(entries, i, svn_fs_fs__p2l_entry_t);
3310 if (entry->type == SVN_FS_FS__ITEM_TYPE_UNUSED)
3313 /* the item / container we were looking for? */
3314 is_wanted = entry->offset == wanted_offset
3315 && entry->item.revision == revision
3316 && entry->item.number == item_index;
3317 is_result = result && is_wanted;
3319 /* select the pool that we want the item to be allocated in */
3320 pool = is_result ? result_pool : iterpool;
3322 /* handle all items that start within this block and are relatively
3323 * small (i.e. < block size). Always read the item we need to return.
3325 if (is_result || ( entry->offset >= block_start
3326 && entry->size < ffd->block_size))
3329 SVN_ERR(svn_io_file_seek(revision_file->file, APR_SET,
3330 &entry->offset, iterpool));
3331 switch (entry->type)
3333 case SVN_FS_FS__ITEM_TYPE_FILE_REP:
3334 case SVN_FS_FS__ITEM_TYPE_DIR_REP:
3335 case SVN_FS_FS__ITEM_TYPE_FILE_PROPS:
3336 case SVN_FS_FS__ITEM_TYPE_DIR_PROPS:
3337 SVN_ERR(block_read_contents(fs, revision_file, entry,
3340 : block_start + ffd->block_size,
3344 case SVN_FS_FS__ITEM_TYPE_NODEREV:
3345 if (ffd->node_revision_cache || is_result)
3346 SVN_ERR(block_read_noderev((node_revision_t **)&item,
3348 entry, is_result, pool,
3352 case SVN_FS_FS__ITEM_TYPE_CHANGES:
3353 SVN_ERR(block_read_changes((apr_array_header_t **)&item,
3366 /* if we crossed a block boundary, read the remainder of
3367 * the last block as well */
3368 offset = entry->offset + entry->size;
3369 if (offset > block_start + ffd->block_size)
3375 while(run_count++ == 1); /* can only be true once and only if a block
3376 * boundary got crossed */
3378 /* if the caller requested a result, we must have provided one by now */
3379 assert(!result || *result);
3380 svn_pool_destroy(iterpool);
3382 return SVN_NO_ERROR;