/* index.c indexing support for FSX support * * ==================================================================== * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. * ==================================================================== */ #include #include "svn_io.h" #include "svn_pools.h" #include "svn_sorts.h" #include "index.h" #include "util.h" #include "pack.h" #include "private/svn_dep_compat.h" #include "private/svn_sorts_private.h" #include "private/svn_subr_private.h" #include "private/svn_temp_serializer.h" #include "svn_private_config.h" #include "temp_serializer.h" #include "fs_x.h" #include "../libsvn_fs/fs-loader.h" /* maximum length of a uint64 in an 7/8b encoding */ #define ENCODED_INT_LENGTH 10 /* APR is missing an APR_OFF_T_MAX. So, define one. We will use it to * limit file offsets stored in the indexes. * * We assume that everything shorter than 64 bits, it is at least 32 bits. * We also assume that the type is always signed meaning we only have an * effective positive range of 63 or 31 bits, respectively. */ static const apr_uint64_t off_t_max = (sizeof(apr_off_t) == sizeof(apr_int64_t)) ? APR_INT64_MAX : APR_INT32_MAX; /* We store P2L proto-index entries as 6 values, 64 bits each on disk. * See also svn_fs_fs__p2l_proto_index_add_entry(). */ #define P2L_PROTO_INDEX_ENTRY_SIZE (6 * sizeof(apr_uint64_t)) /* We put this string in front of the L2P index header. */ #define L2P_STREAM_PREFIX "L2P-INDEX\n" /* We put this string in front of the P2L index header. */ #define P2L_STREAM_PREFIX "P2L-INDEX\n" /* Size of the buffer that will fit the index header prefixes. */ #define STREAM_PREFIX_LEN MAX(sizeof(L2P_STREAM_PREFIX), \ sizeof(P2L_STREAM_PREFIX)) /* Page tables in the log-to-phys index file exclusively contain entries * of this type to describe position and size of a given page. */ typedef struct l2p_page_table_entry_t { /* global offset on the page within the index file */ apr_uint64_t offset; /* number of mapping entries in that page */ apr_uint32_t entry_count; /* size of the page on disk (in the index file) */ apr_uint32_t size; } l2p_page_table_entry_t; /* Master run-time data structure of an log-to-phys index. It contains * the page tables of every revision covered by that index - but not the * pages themselves. */ typedef struct l2p_header_t { /* first revision covered by this index */ svn_revnum_t first_revision; /* number of revisions covered */ apr_size_t revision_count; /* (max) number of entries per page */ apr_uint32_t page_size; /* indexes into PAGE_TABLE that mark the first page of the respective * revision. PAGE_TABLE_INDEX[REVISION_COUNT] points to the end of * PAGE_TABLE. */ apr_size_t * page_table_index; /* Page table covering all pages in the index */ l2p_page_table_entry_t * page_table; } l2p_header_t; /* Run-time data structure containing a single log-to-phys index page. */ typedef struct l2p_page_t { /* number of entries in the OFFSETS array */ apr_uint32_t entry_count; /* global file offsets (item index is the array index) within the * packed or non-packed rev file. Offset will be -1 for unused / * invalid item index values. */ apr_off_t *offsets; /* In case that the item is stored inside a container, this is the * identifying index of the item within that container. 0 for the * container itself or for items that aren't containers. */ apr_uint32_t *sub_items; } l2p_page_t; /* All of the log-to-phys proto index file consist of entries of this type. */ typedef struct l2p_proto_entry_t { /* phys offset + 1 of the data container. 0 for "new revision" entries. */ apr_uint64_t offset; /* corresponding item index. 0 for "new revision" entries. */ apr_uint64_t item_index; /* index within the container starting @ offset. 0 for "new revision" * entries and for items with no outer container. */ apr_uint32_t sub_item; } l2p_proto_entry_t; /* Master run-time data structure of an phys-to-log index. It contains * an array with one offset value for each rev file cluster. */ typedef struct p2l_header_t { /* first revision covered by the index (and rev file) */ svn_revnum_t first_revision; /* number of bytes in the rev files covered by each p2l page */ apr_uint64_t page_size; /* number of pages / clusters in that rev file */ apr_size_t page_count; /* number of bytes in the rev file */ apr_uint64_t file_size; /* offsets of the pages / cluster descriptions within the index file */ apr_off_t *offsets; } p2l_header_t; /* * packed stream array */ /* How many numbers we will pre-fetch and buffer in a packed number stream. */ enum { MAX_NUMBER_PREFETCH = 64 }; /* Prefetched number entry in a packed number stream. */ typedef struct value_position_pair_t { /* prefetched number */ apr_uint64_t value; /* number of bytes read, *including* this number, since the buffer start */ apr_size_t total_len; } value_position_pair_t; /* State of a prefetching packed number stream. It will read compressed * index data efficiently and present it as a series of non-packed uint64. */ struct svn_fs_x__packed_number_stream_t { /* underlying data file containing the packed values */ apr_file_t *file; /* Offset within FILE at which the stream data starts * (i.e. which offset will reported as offset 0 by packed_stream_offset). */ apr_off_t stream_start; /* First offset within FILE after the stream data. * Attempts to read beyond this will cause an "Unexpected End Of Stream" * error. */ apr_off_t stream_end; /* number of used entries in BUFFER (starting at index 0) */ apr_size_t used; /* index of the next number to read from the BUFFER (0 .. USED). * If CURRENT == USED, we need to read more data upon get() */ apr_size_t current; /* offset in FILE from which the first entry in BUFFER has been read */ apr_off_t start_offset; /* offset in FILE from which the next number has to be read */ apr_off_t next_offset; /* read the file in chunks of this size */ apr_size_t block_size; /* pool to be used for file ops etc. */ apr_pool_t *pool; /* buffer for prefetched values */ value_position_pair_t buffer[MAX_NUMBER_PREFETCH]; }; /* Return an svn_error_t * object for error ERR on STREAM with the given * MESSAGE string. The latter must have a placeholder for the index file * name ("%s") and the current read offset (e.g. "0x%lx"). */ static svn_error_t * stream_error_create(svn_fs_x__packed_number_stream_t *stream, apr_status_t err, const char *message) { const char *file_name; apr_off_t offset; SVN_ERR(svn_io_file_name_get(&file_name, stream->file, stream->pool)); SVN_ERR(svn_fs_x__get_file_offset(&offset, stream->file, stream->pool)); return svn_error_createf(err, NULL, message, file_name, apr_psprintf(stream->pool, "%" APR_UINT64_T_HEX_FMT, (apr_uint64_t)offset)); } /* Read up to MAX_NUMBER_PREFETCH numbers from the STREAM->NEXT_OFFSET in * STREAM->FILE and buffer them. * * We don't want GCC and others to inline this (infrequently called) * function into packed_stream_get() because it prevents the latter from * being inlined itself. */ SVN__PREVENT_INLINE static svn_error_t * packed_stream_read(svn_fs_x__packed_number_stream_t *stream) { unsigned char buffer[MAX_NUMBER_PREFETCH]; apr_size_t read = 0; apr_size_t i; value_position_pair_t *target; apr_off_t block_start = 0; apr_off_t block_left = 0; apr_status_t err; /* all buffered data will have been read starting here */ stream->start_offset = stream->next_offset; /* packed numbers are usually not aligned to MAX_NUMBER_PREFETCH blocks, * i.e. the last number has been incomplete (and not buffered in stream) * and need to be re-read. Therefore, always correct the file pointer. */ SVN_ERR(svn_io_file_aligned_seek(stream->file, stream->block_size, &block_start, stream->next_offset, stream->pool)); /* prefetch at least one number but, if feasible, don't cross block * boundaries. This shall prevent jumping back and forth between two * blocks because the extra data was not actually request _now_. */ read = sizeof(buffer); block_left = stream->block_size - (stream->next_offset - block_start); if (block_left >= 10 && block_left < read) read = (apr_size_t)block_left; /* Don't read beyond the end of the file section that belongs to this * index / stream. */ read = (apr_size_t)MIN(read, stream->stream_end - stream->next_offset); err = apr_file_read(stream->file, buffer, &read); if (err && !APR_STATUS_IS_EOF(err)) return stream_error_create(stream, err, _("Can't read index file '%s' at offset 0x%")); /* if the last number is incomplete, trim it from the buffer */ while (read > 0 && buffer[read-1] >= 0x80) --read; /* we call read() only if get() requires more data. So, there must be * at least *one* further number. */ if SVN__PREDICT_FALSE(read == 0) return stream_error_create(stream, err, _("Unexpected end of index file %s at offset 0x%")); /* parse file buffer and expand into stream buffer */ target = stream->buffer; for (i = 0; i < read;) { if (buffer[i] < 0x80) { /* numbers < 128 are relatively frequent and particularly easy * to decode. Give them special treatment. */ target->value = buffer[i]; ++i; target->total_len = i; ++target; } else { apr_uint64_t value = 0; apr_uint64_t shift = 0; while (buffer[i] >= 0x80) { value += ((apr_uint64_t)buffer[i] & 0x7f) << shift; shift += 7; ++i; } target->value = value + ((apr_uint64_t)buffer[i] << shift); ++i; target->total_len = i; ++target; /* let's catch corrupted data early. It would surely cause * havoc further down the line. */ if SVN__PREDICT_FALSE(shift > 8 * sizeof(value)) return svn_error_createf(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Corrupt index: number too large")); } } /* update stream state */ stream->used = target - stream->buffer; stream->next_offset = stream->start_offset + i; stream->current = 0; return SVN_NO_ERROR; } /* Create and open a packed number stream reading from offsets START to * END in FILE and return it in *STREAM. Access the file in chunks of * BLOCK_SIZE bytes. Expect the stream to be prefixed by STREAM_PREFIX. * Allocate *STREAM in RESULT_POOL and use SCRATCH_POOL for temporaries. */ static svn_error_t * packed_stream_open(svn_fs_x__packed_number_stream_t **stream, apr_file_t *file, apr_off_t start, apr_off_t end, const char *stream_prefix, apr_size_t block_size, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { char buffer[STREAM_PREFIX_LEN + 1] = { 0 }; apr_size_t len = strlen(stream_prefix); svn_fs_x__packed_number_stream_t *result; /* If this is violated, we forgot to adjust STREAM_PREFIX_LEN after * changing the index header prefixes. */ SVN_ERR_ASSERT(len < sizeof(buffer)); /* Read the header prefix and compare it with the expected prefix */ SVN_ERR(svn_io_file_aligned_seek(file, block_size, NULL, start, scratch_pool)); SVN_ERR(svn_io_file_read_full2(file, buffer, len, NULL, NULL, scratch_pool)); if (strncmp(buffer, stream_prefix, len)) return svn_error_createf(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Index stream header prefix mismatch.\n" " expected: %s" " found: %s"), stream_prefix, buffer); /* Construct the actual stream object. */ result = apr_palloc(result_pool, sizeof(*result)); result->pool = result_pool; result->file = file; result->stream_start = start + len; result->stream_end = end; result->used = 0; result->current = 0; result->start_offset = result->stream_start; result->next_offset = result->stream_start; result->block_size = block_size; *stream = result; return SVN_NO_ERROR; } /* * The forced inline is required for performance reasons: This is a very * hot code path (called for every item we read) but e.g. GCC would rather * chose to inline packed_stream_read() here, preventing packed_stream_get * from being inlined itself. */ SVN__FORCE_INLINE static svn_error_t* packed_stream_get(apr_uint64_t *value, svn_fs_x__packed_number_stream_t *stream) { if (stream->current == stream->used) SVN_ERR(packed_stream_read(stream)); *value = stream->buffer[stream->current].value; ++stream->current; return SVN_NO_ERROR; } /* Navigate STREAM to packed stream offset OFFSET. There will be no checks * whether the given OFFSET is valid. */ static void packed_stream_seek(svn_fs_x__packed_number_stream_t *stream, apr_off_t offset) { apr_off_t file_offset = offset + stream->stream_start; if ( stream->used == 0 || offset < stream->start_offset || offset >= stream->next_offset) { /* outside buffered data. Next get() will read() from OFFSET. */ stream->start_offset = file_offset; stream->next_offset = file_offset; stream->current = 0; stream->used = 0; } else { /* Find the suitable location in the stream buffer. * Since our buffer is small, it is efficient enough to simply scan * it for the desired position. */ apr_size_t i; for (i = 0; i < stream->used; ++i) if (stream->buffer[i].total_len > file_offset - stream->start_offset) break; stream->current = i; } } /* Return the packed stream offset of at which the next number in the stream * can be found. */ static apr_off_t packed_stream_offset(svn_fs_x__packed_number_stream_t *stream) { apr_off_t file_offset = stream->current == 0 ? stream->start_offset : stream->buffer[stream->current-1].total_len + stream->start_offset; return file_offset - stream->stream_start; } /* Write VALUE to the PROTO_INDEX file, using SCRATCH_POOL for temporary * allocations. * * The point of this function is to ensure an architecture-independent * proto-index file format. All data is written as unsigned 64 bits ints * in little endian byte order. 64 bits is the largest portable integer * we have and unsigned values have well-defined conversions in C. */ static svn_error_t * write_uint64_to_proto_index(apr_file_t *proto_index, apr_uint64_t value, apr_pool_t *scratch_pool) { apr_byte_t buffer[sizeof(value)]; int i; apr_size_t written; /* Split VALUE into 8 bytes using LE ordering. */ for (i = 0; i < sizeof(buffer); ++i) { /* Unsigned conversions are well-defined ... */ buffer[i] = (apr_byte_t)value; value >>= CHAR_BIT; } /* Write it all to disk. */ SVN_ERR(svn_io_file_write_full(proto_index, buffer, sizeof(buffer), &written, scratch_pool)); SVN_ERR_ASSERT(written == sizeof(buffer)); return SVN_NO_ERROR; } /* Read one unsigned 64 bit value from PROTO_INDEX file and return it in * *VALUE_P. If EOF is NULL, error out when trying to read beyond EOF. * Use SCRATCH_POOL for temporary allocations. * * This function is the inverse to write_uint64_to_proto_index (see there), * reading the external LE byte order and convert it into host byte order. */ static svn_error_t * read_uint64_from_proto_index(apr_file_t *proto_index, apr_uint64_t *value_p, svn_boolean_t *eof, apr_pool_t *scratch_pool) { apr_byte_t buffer[sizeof(*value_p)]; apr_size_t read; /* Read the full 8 bytes or our 64 bit value, unless we hit EOF. * Assert that we never read partial values. */ SVN_ERR(svn_io_file_read_full2(proto_index, buffer, sizeof(buffer), &read, eof, scratch_pool)); SVN_ERR_ASSERT((eof && *eof) || read == sizeof(buffer)); /* If we did not hit EOF, reconstruct the uint64 value and return it. */ if (!eof || !*eof) { int i; apr_uint64_t value; /* This could only overflow if CHAR_BIT had a value that is not * a divisor of 64. */ value = 0; for (i = sizeof(buffer) - 1; i >= 0; --i) value = (value << CHAR_BIT) + buffer[i]; *value_p = value; } return SVN_NO_ERROR; } /* Convenience function similar to read_uint64_from_proto_index, but returns * an uint32 value in VALUE_P. Return an error if the value does not fit. */ static svn_error_t * read_uint32_from_proto_index(apr_file_t *proto_index, apr_uint32_t *value_p, svn_boolean_t *eof, apr_pool_t *scratch_pool) { apr_uint64_t value; SVN_ERR(read_uint64_from_proto_index(proto_index, &value, eof, scratch_pool)); if (!eof || !*eof) { if (value > APR_UINT32_MAX) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW, NULL, _("UINT32 0x%s too large, max = 0x%s"), apr_psprintf(scratch_pool, "%" APR_UINT64_T_HEX_FMT, value), apr_psprintf(scratch_pool, "%" APR_UINT64_T_HEX_FMT, (apr_uint64_t)APR_UINT32_MAX)); /* This conversion is not lossy because the value can be represented * in the target type. */ *value_p = (apr_uint32_t)value; } return SVN_NO_ERROR; } /* Convenience function similar to read_uint64_from_proto_index, but returns * an off_t value in VALUE_P. Return an error if the value does not fit. */ static svn_error_t * read_off_t_from_proto_index(apr_file_t *proto_index, apr_off_t *value_p, svn_boolean_t *eof, apr_pool_t *scratch_pool) { apr_uint64_t value; SVN_ERR(read_uint64_from_proto_index(proto_index, &value, eof, scratch_pool)); if (!eof || !*eof) { if (value > off_t_max) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW, NULL, _("File offset 0x%s too large, max = 0x%s"), apr_psprintf(scratch_pool, "%" APR_UINT64_T_HEX_FMT, value), apr_psprintf(scratch_pool, "%" APR_UINT64_T_HEX_FMT, off_t_max)); /* Shortening conversion from unsigned to signed int is well-defined * and not lossy in C because the value can be represented in the * target type. */ *value_p = (apr_off_t)value; } return SVN_NO_ERROR; } /* * log-to-phys index */ svn_error_t * svn_fs_x__l2p_proto_index_open(apr_file_t **proto_index, const char *file_name, apr_pool_t *result_pool) { SVN_ERR(svn_io_file_open(proto_index, file_name, APR_READ | APR_WRITE | APR_CREATE | APR_APPEND | APR_BUFFERED, APR_OS_DEFAULT, result_pool)); return SVN_NO_ERROR; } /* Append ENTRY to log-to-phys PROTO_INDEX file. * Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * write_l2p_entry_to_proto_index(apr_file_t *proto_index, l2p_proto_entry_t entry, apr_pool_t *scratch_pool) { SVN_ERR(write_uint64_to_proto_index(proto_index, entry.offset, scratch_pool)); SVN_ERR(write_uint64_to_proto_index(proto_index, entry.item_index, scratch_pool)); SVN_ERR(write_uint64_to_proto_index(proto_index, entry.sub_item, scratch_pool)); return SVN_NO_ERROR; } /* Read *ENTRY from log-to-phys PROTO_INDEX file and indicate end-of-file * in *EOF, or error out in that case if EOF is NULL. *ENTRY is in an * undefined state if an end-of-file occurred. * Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * read_l2p_entry_from_proto_index(apr_file_t *proto_index, l2p_proto_entry_t *entry, svn_boolean_t *eof, apr_pool_t *scratch_pool) { SVN_ERR(read_uint64_from_proto_index(proto_index, &entry->offset, eof, scratch_pool)); SVN_ERR(read_uint64_from_proto_index(proto_index, &entry->item_index, eof, scratch_pool)); SVN_ERR(read_uint32_from_proto_index(proto_index, &entry->sub_item, eof, scratch_pool)); return SVN_NO_ERROR; } svn_error_t * svn_fs_x__l2p_proto_index_add_revision(apr_file_t *proto_index, apr_pool_t *scratch_pool) { l2p_proto_entry_t entry = { 0 }; return svn_error_trace(write_l2p_entry_to_proto_index(proto_index, entry, scratch_pool)); } svn_error_t * svn_fs_x__l2p_proto_index_add_entry(apr_file_t *proto_index, apr_off_t offset, apr_uint32_t sub_item, apr_uint64_t item_index, apr_pool_t *scratch_pool) { l2p_proto_entry_t entry = { 0 }; /* make sure the conversion to uint64 works */ SVN_ERR_ASSERT(offset >= -1); /* we support offset '-1' as a "not used" indication */ entry.offset = (apr_uint64_t)offset + 1; /* make sure we can use item_index as an array index when building the * final index file */ SVN_ERR_ASSERT(item_index < UINT_MAX / 2); entry.item_index = item_index; /* no limits on the container sub-item index */ entry.sub_item = sub_item; return svn_error_trace(write_l2p_entry_to_proto_index(proto_index, entry, scratch_pool)); } /* Encode VALUE as 7/8b into P and return the number of bytes written. * This will be used when _writing_ packed data. packed_stream_* is for * read operations only. */ static apr_size_t encode_uint(unsigned char *p, apr_uint64_t value) { unsigned char *start = p; while (value >= 0x80) { *p = (unsigned char)((value % 0x80) + 0x80); value /= 0x80; ++p; } *p = (unsigned char)(value % 0x80); return (p - start) + 1; } /* Encode VALUE as 7/8b into P and return the number of bytes written. * This maps signed ints onto unsigned ones. */ static apr_size_t encode_int(unsigned char *p, apr_int64_t value) { return encode_uint(p, (apr_uint64_t)(value < 0 ? -1 - 2*value : 2*value)); } /* Append VALUE to STREAM in 7/8b encoding. */ static svn_error_t * stream_write_encoded(svn_stream_t *stream, apr_uint64_t value) { unsigned char encoded[ENCODED_INT_LENGTH]; apr_size_t len = encode_uint(encoded, value); return svn_error_trace(svn_stream_write(stream, (char *)encoded, &len)); } /* Run-length-encode the uint64 numbers in ARRAY starting at index START * up to but not including END. All numbers must be > 0. * Return the number of remaining entries in ARRAY after START. */ static int rle_array(apr_array_header_t *array, int start, int end) { int i; int target = start; for (i = start; i < end; ++i) { apr_uint64_t value = APR_ARRAY_IDX(array, i, apr_uint64_t); assert(value > 0); if (value == 1) { int counter; for (counter = 1; i + counter < end; ++counter) if (APR_ARRAY_IDX(array, i + counter, apr_uint64_t) != 1) break; if (--counter) { APR_ARRAY_IDX(array, target, apr_uint64_t) = 0; APR_ARRAY_IDX(array, target + 1, apr_uint64_t) = counter; target += 2; i += counter; continue; } } APR_ARRAY_IDX(array, target, apr_uint64_t) = value; ++target; } return target; } /* Utility data structure describing an log-2-phys page entry. * This is only used as a transient representation during index creation. */ typedef struct l2p_page_entry_t { apr_uint64_t offset; apr_uint32_t sub_item; } l2p_page_entry_t; /* qsort-compatible compare function taking two l2p_page_entry_t and * ordering them by offset. */ static int compare_l2p_entries_by_offset(const l2p_page_entry_t *lhs, const l2p_page_entry_t *rhs) { return lhs->offset > rhs->offset ? 1 : lhs->offset == rhs->offset ? 0 : -1; } /* Write the log-2-phys index page description for the l2p_page_entry_t * array ENTRIES, starting with element START up to but not including END. * Write the resulting representation into BUFFER. Use SCRATCH_POOL for * temporary allocations. */ static svn_error_t * encode_l2p_page(apr_array_header_t *entries, int start, int end, svn_spillbuf_t *buffer, apr_pool_t *scratch_pool) { unsigned char encoded[ENCODED_INT_LENGTH]; apr_hash_t *containers = apr_hash_make(scratch_pool); int count = end - start; int container_count = 0; apr_uint64_t last_offset = 0; int i; apr_size_t data_size = count * sizeof(l2p_page_entry_t); svn_stringbuf_t *container_offsets = svn_stringbuf_create_ensure(count * 2, scratch_pool); /* SORTED: relevant items from ENTRIES, sorted by offset */ l2p_page_entry_t *sorted = apr_pmemdup(scratch_pool, entries->elts + start * sizeof(l2p_page_entry_t), data_size); qsort(sorted, end - start, sizeof(l2p_page_entry_t), (int (*)(const void *, const void *))compare_l2p_entries_by_offset); /* identify container offsets and create container list */ for (i = 0; i < count; ++i) { /* skip "unused" entries */ if (sorted[i].offset == 0) continue; /* offset already covered? */ if (i > 0 && sorted[i].offset == sorted[i-1].offset) continue; /* is this a container item * (appears more than once or accesses to sub-items other than 0)? */ if ( (i != count-1 && sorted[i].offset == sorted[i+1].offset) || (sorted[i].sub_item != 0)) { svn_stringbuf_appendbytes(container_offsets, (const char *)encoded, encode_uint(encoded, sorted[i].offset - last_offset)); last_offset = sorted[i].offset; apr_hash_set(containers, &sorted[i].offset, sizeof(sorted[i].offset), (void *)(apr_uintptr_t)++container_count); } } /* write container list to BUFFER */ SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_uint(encoded, container_count), scratch_pool)); SVN_ERR(svn_spillbuf__write(buffer, (const char *)container_offsets->data, container_offsets->len, scratch_pool)); /* encode items */ for (i = start; i < end; ++i) { l2p_page_entry_t *entry = &APR_ARRAY_IDX(entries, i, l2p_page_entry_t); if (entry->offset == 0) { SVN_ERR(svn_spillbuf__write(buffer, "\0", 1, scratch_pool)); } else { void *void_idx = apr_hash_get(containers, &entry->offset, sizeof(entry->offset)); if (void_idx == NULL) { apr_uint64_t value = entry->offset + container_count; SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_uint(encoded, value), scratch_pool)); } else { apr_uintptr_t idx = (apr_uintptr_t)void_idx; apr_uint64_t value = entry->sub_item; SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_uint(encoded, idx), scratch_pool)); SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_uint(encoded, value), scratch_pool)); } } } return SVN_NO_ERROR; } svn_error_t * svn_fs_x__l2p_index_append(svn_checksum_t **checksum, svn_fs_t *fs, apr_file_t *index_file, const char *proto_file_name, svn_revnum_t revision, apr_pool_t * result_pool, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; apr_file_t *proto_index = NULL; svn_stream_t *stream; int i; int end; apr_uint64_t entry; svn_boolean_t eof = FALSE; int last_page_count = 0; /* total page count at the start of the current revision */ /* temporary data structures that collect the data which will be moved to the target file in a second step */ apr_pool_t *local_pool = svn_pool_create(scratch_pool); apr_pool_t *iterpool = svn_pool_create(local_pool); apr_array_header_t *page_counts = apr_array_make(local_pool, 16, sizeof(apr_uint64_t)); apr_array_header_t *page_sizes = apr_array_make(local_pool, 16, sizeof(apr_uint64_t)); apr_array_header_t *entry_counts = apr_array_make(local_pool, 16, sizeof(apr_uint64_t)); /* collect the item offsets and sub-item value for the current revision */ apr_array_header_t *entries = apr_array_make(local_pool, 256, sizeof(l2p_page_entry_t)); /* 64k blocks, spill after 16MB */ svn_spillbuf_t *buffer = svn_spillbuf__create(0x10000, 0x1000000, local_pool); /* Paranoia check that makes later casting to int32 safe. * The current implementation is limited to 2G entries per page. */ if (ffd->l2p_page_size > APR_INT32_MAX) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL, _("L2P index page size %s" " exceeds current limit of 2G entries"), apr_psprintf(local_pool, "%" APR_UINT64_T_FMT, ffd->l2p_page_size)); /* start at the beginning of the source file */ SVN_ERR(svn_io_file_open(&proto_index, proto_file_name, APR_READ | APR_CREATE | APR_BUFFERED, APR_OS_DEFAULT, local_pool)); /* process all entries until we fail due to EOF */ for (entry = 0; !eof; ++entry) { l2p_proto_entry_t proto_entry; /* (attempt to) read the next entry from the source */ SVN_ERR(read_l2p_entry_from_proto_index(proto_index, &proto_entry, &eof, local_pool)); /* handle new revision */ if ((entry > 0 && proto_entry.offset == 0) || eof) { /* dump entries, grouped into pages */ int entry_count = 0; for (i = 0; i < entries->nelts; i += entry_count) { /* 1 page with up to L2P_PAGE_SIZE entries. * fsfs.conf settings validation guarantees this to fit into * our address space. */ apr_size_t last_buffer_size = (apr_size_t)svn_spillbuf__get_size(buffer); svn_pool_clear(iterpool); entry_count = ffd->l2p_page_size < entries->nelts - i ? (int)ffd->l2p_page_size : entries->nelts - i; SVN_ERR(encode_l2p_page(entries, i, i + entry_count, buffer, iterpool)); APR_ARRAY_PUSH(entry_counts, apr_uint64_t) = entry_count; APR_ARRAY_PUSH(page_sizes, apr_uint64_t) = svn_spillbuf__get_size(buffer) - last_buffer_size; } apr_array_clear(entries); /* store the number of pages in this revision */ APR_ARRAY_PUSH(page_counts, apr_uint64_t) = page_sizes->nelts - last_page_count; last_page_count = page_sizes->nelts; } else { int idx; /* store the mapping in our array */ l2p_page_entry_t page_entry = { 0 }; if (proto_entry.item_index > APR_INT32_MAX) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL, _("Item index %s too large " "in l2p proto index for revision %ld"), apr_psprintf(local_pool, "%" APR_UINT64_T_FMT, proto_entry.item_index), revision + page_counts->nelts); idx = (int)proto_entry.item_index; while (idx >= entries->nelts) APR_ARRAY_PUSH(entries, l2p_page_entry_t) = page_entry; page_entry.offset = proto_entry.offset; page_entry.sub_item = proto_entry.sub_item; APR_ARRAY_IDX(entries, idx, l2p_page_entry_t) = page_entry; } } /* we are now done with the source file */ SVN_ERR(svn_io_file_close(proto_index, local_pool)); /* Paranoia check that makes later casting to int32 safe. * The current implementation is limited to 2G pages per index. */ if (page_counts->nelts > APR_INT32_MAX) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL, _("L2P index page count %d" " exceeds current limit of 2G pages"), page_counts->nelts); /* open target stream. */ stream = svn_stream_checksummed2(svn_stream_from_aprfile2(index_file, TRUE, local_pool), NULL, checksum, svn_checksum_md5, FALSE, result_pool); /* write header info */ SVN_ERR(svn_stream_puts(stream, L2P_STREAM_PREFIX)); SVN_ERR(stream_write_encoded(stream, revision)); SVN_ERR(stream_write_encoded(stream, page_counts->nelts)); SVN_ERR(stream_write_encoded(stream, ffd->l2p_page_size)); SVN_ERR(stream_write_encoded(stream, page_sizes->nelts)); /* write the revision table */ end = rle_array(page_counts, 0, page_counts->nelts); for (i = 0; i < end; ++i) { apr_uint64_t value = APR_ARRAY_IDX(page_counts, i, apr_uint64_t); SVN_ERR(stream_write_encoded(stream, value)); } /* write the page table */ for (i = 0; i < page_sizes->nelts; ++i) { apr_uint64_t value = APR_ARRAY_IDX(page_sizes, i, apr_uint64_t); SVN_ERR(stream_write_encoded(stream, value)); value = APR_ARRAY_IDX(entry_counts, i, apr_uint64_t); SVN_ERR(stream_write_encoded(stream, value)); } /* append page contents and implicitly close STREAM */ SVN_ERR(svn_stream_copy3(svn_stream__from_spillbuf(buffer, local_pool), stream, NULL, NULL, local_pool)); svn_pool_destroy(local_pool); return SVN_NO_ERROR; } /* Return the base revision used to identify the p2l or lp2 index covering * REVISION in FS. */ static svn_revnum_t base_revision(svn_fs_t *fs, svn_revnum_t revision) { svn_fs_x__data_t *ffd = fs->fsap_data; return svn_fs_x__is_packed_rev(fs, revision) ? revision - (revision % ffd->max_files_per_dir) : revision; } /* Data structure that describes which l2p page info shall be extracted * from the cache and contains the fields that receive the result. */ typedef struct l2p_page_info_baton_t { /* input data: we want the page covering (REVISION,ITEM_INDEX) */ svn_revnum_t revision; apr_uint64_t item_index; /* out data */ /* page location and size of the page within the l2p index file */ l2p_page_table_entry_t entry; /* page number within the pages for REVISION (not l2p index global!) */ apr_uint32_t page_no; /* offset of ITEM_INDEX within that page */ apr_uint32_t page_offset; /* revision identifying the l2p index file, also the first rev in that */ svn_revnum_t first_revision; } l2p_page_info_baton_t; /* Utility function that copies the info requested by BATON->REVISION and * BATON->ITEM_INDEX and from HEADER and PAGE_TABLE into the output fields * of *BATON. Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * l2p_header_copy(l2p_page_info_baton_t *baton, const l2p_header_t *header, const l2p_page_table_entry_t *page_table, const apr_size_t *page_table_index, apr_pool_t *scratch_pool) { /* revision offset within the index file */ apr_size_t rel_revision = baton->revision - header->first_revision; if (rel_revision >= header->revision_count) return svn_error_createf(SVN_ERR_FS_INDEX_REVISION , NULL, _("Revision %ld not covered by item index"), baton->revision); /* select the relevant page */ if (baton->item_index < header->page_size) { /* most revs fit well into a single page */ baton->page_offset = (apr_uint32_t)baton->item_index; baton->page_no = 0; baton->entry = page_table[page_table_index[rel_revision]]; } else { const l2p_page_table_entry_t *first_entry; const l2p_page_table_entry_t *last_entry; apr_uint64_t max_item_index; /* range of pages for this rev */ first_entry = page_table + page_table_index[rel_revision]; last_entry = page_table + page_table_index[rel_revision + 1]; /* do we hit a valid index page? */ max_item_index = (apr_uint64_t)header->page_size * (last_entry - first_entry); if (baton->item_index >= max_item_index) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL, _("Item index %s exceeds l2p limit " "of %s for revision %ld"), apr_psprintf(scratch_pool, "%" APR_UINT64_T_FMT, baton->item_index), apr_psprintf(scratch_pool, "%" APR_UINT64_T_FMT, max_item_index), baton->revision); /* all pages are of the same size and full, except for the last one */ baton->page_offset = (apr_uint32_t)(baton->item_index % header->page_size); baton->page_no = (apr_uint32_t)(baton->item_index / header->page_size); baton->entry = first_entry[baton->page_no]; } baton->first_revision = header->first_revision; return SVN_NO_ERROR; } /* Implement svn_cache__partial_getter_func_t: copy the data requested in * l2p_page_info_baton_t *BATON from l2p_header_t *DATA into the output * fields in *BATON. */ static svn_error_t * l2p_header_access_func(void **out, const void *data, apr_size_t data_len, void *baton, apr_pool_t *result_pool) { /* resolve all pointer values of in-cache data */ const l2p_header_t *header = data; const l2p_page_table_entry_t *page_table = svn_temp_deserializer__ptr(header, (const void *const *)&header->page_table); const apr_size_t *page_table_index = svn_temp_deserializer__ptr(header, (const void *const *)&header->page_table_index); /* copy the info */ return l2p_header_copy(baton, header, page_table, page_table_index, result_pool); } /* Read COUNT run-length-encoded (see rle_array) uint64 from STREAM and * return them in VALUES. */ static svn_error_t * expand_rle(apr_array_header_t *values, svn_fs_x__packed_number_stream_t *stream, apr_size_t count) { apr_array_clear(values); while (count) { apr_uint64_t value; SVN_ERR(packed_stream_get(&value, stream)); if (value) { APR_ARRAY_PUSH(values, apr_uint64_t) = value; --count; } else { apr_uint64_t i; apr_uint64_t repetitions; SVN_ERR(packed_stream_get(&repetitions, stream)); if (++repetitions > count) repetitions = count; for (i = 0; i < repetitions; ++i) APR_ARRAY_PUSH(values, apr_uint64_t) = 1; count -= repetitions; } } return SVN_NO_ERROR; } /* If REV_FILE->L2P_STREAM is NULL, create a new stream for the log-to-phys * index for REVISION in FS and return it in REV_FILE. */ static svn_error_t * auto_open_l2p_index(svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t revision) { if (rev_file->l2p_stream == NULL) { svn_fs_x__data_t *ffd = fs->fsap_data; SVN_ERR(svn_fs_x__auto_read_footer(rev_file)); SVN_ERR(packed_stream_open(&rev_file->l2p_stream, rev_file->file, rev_file->l2p_offset, rev_file->p2l_offset, L2P_STREAM_PREFIX, (apr_size_t)ffd->block_size, rev_file->pool, rev_file->pool)); } return SVN_NO_ERROR; } /* Read the header data structure of the log-to-phys index for REVISION * in FS and return it in *HEADER, allocated in RESULT_POOL. Use REV_FILE * to access on-disk data. Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * get_l2p_header_body(l2p_header_t **header, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t revision, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; apr_uint64_t value; apr_size_t i; apr_size_t page, page_count; apr_off_t offset; l2p_header_t *result = apr_pcalloc(result_pool, sizeof(*result)); apr_size_t page_table_index; svn_revnum_t next_rev; apr_array_header_t *expanded_values = apr_array_make(scratch_pool, 16, sizeof(apr_uint64_t)); svn_fs_x__pair_cache_key_t key; key.revision = rev_file->start_revision; key.second = rev_file->is_packed; SVN_ERR(auto_open_l2p_index(rev_file, fs, revision)); packed_stream_seek(rev_file->l2p_stream, 0); /* Read the table sizes. Check the data for plausibility and * consistency with other bits. */ SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream)); result->first_revision = (svn_revnum_t)value; if (result->first_revision != rev_file->start_revision) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Index rev / pack file revision numbers do not match")); SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream)); result->revision_count = (int)value; if ( result->revision_count != 1 && result->revision_count != (apr_uint64_t)ffd->max_files_per_dir) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Invalid number of revisions in L2P index")); SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream)); result->page_size = (apr_uint32_t)value; if (!result->page_size || (result->page_size & (result->page_size - 1))) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("L2P index page size is not a power of two")); SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream)); page_count = (apr_size_t)value; if (page_count < result->revision_count) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Fewer L2P index pages than revisions")); if (page_count > (rev_file->p2l_offset - rev_file->l2p_offset) / 2) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("L2P index page count implausibly large")); next_rev = result->first_revision + (svn_revnum_t)result->revision_count; if (result->first_revision > revision || next_rev <= revision) return svn_error_createf(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Corrupt L2P index for r%ld only covers r%ld:%ld"), revision, result->first_revision, next_rev); /* allocate the page tables */ result->page_table = apr_pcalloc(result_pool, page_count * sizeof(*result->page_table)); result->page_table_index = apr_pcalloc(result_pool, (result->revision_count + 1) * sizeof(*result->page_table_index)); /* read per-revision page table sizes (i.e. number of pages per rev) */ page_table_index = 0; result->page_table_index[0] = page_table_index; SVN_ERR(expand_rle(expanded_values, rev_file->l2p_stream, result->revision_count)); for (i = 0; i < result->revision_count; ++i) { value = (apr_size_t)APR_ARRAY_IDX(expanded_values, i, apr_uint64_t); if (value == 0) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Revision with no L2P index pages")); page_table_index += (apr_size_t)value; if (page_table_index > page_count) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("L2P page table exceeded")); result->page_table_index[i+1] = page_table_index; } if (page_table_index != page_count) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Revisions do not cover the full L2P index page table")); /* read actual page tables */ for (page = 0; page < page_count; ++page) { SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream)); if (value == 0) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Empty L2P index page")); result->page_table[page].size = (apr_uint32_t)value; SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream)); if (value > result->page_size) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Page exceeds L2P index page size")); result->page_table[page].entry_count = (apr_uint32_t)value; } /* correct the page description offsets */ offset = packed_stream_offset(rev_file->l2p_stream); for (page = 0; page < page_count; ++page) { result->page_table[page].offset = offset; offset += result->page_table[page].size; } /* return and cache the header */ *header = result; SVN_ERR(svn_cache__set(ffd->l2p_header_cache, &key, result, scratch_pool)); return SVN_NO_ERROR; } /* Get the page info requested in *BATON from FS and set the output fields * in *BATON. * To maximize efficiency, use or return the data stream in *STREAM. * Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * get_l2p_page_info(l2p_page_info_baton_t *baton, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; l2p_header_t *result; svn_boolean_t is_cached = FALSE; void *dummy = NULL; /* try to find the info in the cache */ svn_fs_x__pair_cache_key_t key; key.revision = base_revision(fs, baton->revision); key.second = svn_fs_x__is_packed_rev(fs, baton->revision); SVN_ERR(svn_cache__get_partial((void**)&dummy, &is_cached, ffd->l2p_header_cache, &key, l2p_header_access_func, baton, scratch_pool)); if (is_cached) return SVN_NO_ERROR; /* read from disk, cache and copy the result */ SVN_ERR(get_l2p_header_body(&result, rev_file, fs, baton->revision, scratch_pool, scratch_pool)); SVN_ERR(l2p_header_copy(baton, result, result->page_table, result->page_table_index, scratch_pool)); return SVN_NO_ERROR; } /* Read the log-to-phys header info of the index covering REVISION from FS * and return it in *HEADER. REV_FILE provides the pack / rev status. * Allocate *HEADER in RESULT_POOL, use SCRATCH_POOL for temporary * allocations. */ static svn_error_t * get_l2p_header(l2p_header_t **header, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t revision, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; svn_boolean_t is_cached = FALSE; /* first, try cache lookop */ svn_fs_x__pair_cache_key_t key; key.revision = rev_file->start_revision; key.second = rev_file->is_packed; SVN_ERR(svn_cache__get((void**)header, &is_cached, ffd->l2p_header_cache, &key, result_pool)); if (is_cached) return SVN_NO_ERROR; /* read from disk and cache the result */ SVN_ERR(get_l2p_header_body(header, rev_file, fs, revision, result_pool, scratch_pool)); return SVN_NO_ERROR; } /* From the log-to-phys index file starting at START_REVISION in FS, read * the mapping page identified by TABLE_ENTRY and return it in *PAGE. * Use REV_FILE to access on-disk files. * Use RESULT_POOL for allocations. */ static svn_error_t * get_l2p_page(l2p_page_t **page, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t start_revision, l2p_page_table_entry_t *table_entry, apr_pool_t *result_pool) { apr_uint64_t value, last_value = 0; apr_uint32_t i; l2p_page_t *result = apr_pcalloc(result_pool, sizeof(*result)); apr_uint64_t container_count; apr_off_t *container_offsets; /* open index file and select page */ SVN_ERR(auto_open_l2p_index(rev_file, fs, start_revision)); packed_stream_seek(rev_file->l2p_stream, table_entry->offset); /* initialize the page content */ result->entry_count = table_entry->entry_count; result->offsets = apr_pcalloc(result_pool, result->entry_count * sizeof(*result->offsets)); result->sub_items = apr_pcalloc(result_pool, result->entry_count * sizeof(*result->sub_items)); /* container offsets array */ SVN_ERR(packed_stream_get(&container_count, rev_file->l2p_stream)); container_offsets = apr_pcalloc(result_pool, container_count * sizeof(*result)); for (i = 0; i < container_count; ++i) { SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream)); last_value += value; container_offsets[i] = (apr_off_t)last_value - 1; /* '-1' is represented as '0' in the index file */ } /* read all page entries (offsets in rev file and container sub-items) */ for (i = 0; i < result->entry_count; ++i) { SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream)); if (value == 0) { result->offsets[i] = -1; result->sub_items[i] = 0; } else if (value <= container_count) { result->offsets[i] = container_offsets[value - 1]; SVN_ERR(packed_stream_get(&value, rev_file->l2p_stream)); result->sub_items[i] = (apr_uint32_t)value; } else { result->offsets[i] = (apr_off_t)(value - 1 - container_count); result->sub_items[i] = 0; } } /* After reading all page entries, the read cursor must have moved by * TABLE_ENTRY->SIZE bytes. */ if ( packed_stream_offset(rev_file->l2p_stream) != table_entry->offset + table_entry->size) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("L2P actual page size does not match page table value.")); *page = result; return SVN_NO_ERROR; } /* Request data structure for l2p_page_access_func. */ typedef struct l2p_page_baton_t { /* in data */ /* revision. Used for error messages only */ svn_revnum_t revision; /* item index to look up. Used for error messages only */ apr_uint64_t item_index; /* offset within the cached page */ apr_uint32_t page_offset; /* out data */ /* absolute item or container offset in rev / pack file */ apr_off_t offset; /* 0 -> container / item itself; sub-item in container otherwise */ apr_uint32_t sub_item; } l2p_page_baton_t; /* Return the rev / pack file offset of the item at BATON->PAGE_OFFSET in * OFFSETS of PAGE and write it to *OFFSET. * Allocate temporaries in SCRATCH_POOL. */ static svn_error_t * l2p_page_get_offset(l2p_page_baton_t *baton, const l2p_page_t *page, const apr_off_t *offsets, const apr_uint32_t *sub_items, apr_pool_t *scratch_pool) { /* overflow check */ if (page->entry_count <= baton->page_offset) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL, _("Item index %s too large in" " revision %ld"), apr_psprintf(scratch_pool, "%" APR_UINT64_T_FMT, baton->item_index), baton->revision); /* return the result */ baton->offset = offsets[baton->page_offset]; baton->sub_item = sub_items[baton->page_offset]; return SVN_NO_ERROR; } /* Implement svn_cache__partial_getter_func_t: copy the data requested in * l2p_page_baton_t *BATON from l2p_page_t *DATA into apr_off_t *OUT. */ static svn_error_t * l2p_page_access_func(void **out, const void *data, apr_size_t data_len, void *baton, apr_pool_t *result_pool) { /* resolve all in-cache pointers */ const l2p_page_t *page = data; const apr_off_t *offsets = svn_temp_deserializer__ptr(page, (const void *const *)&page->offsets); const apr_uint32_t *sub_items = svn_temp_deserializer__ptr(page, (const void *const *)&page->sub_items); /* return the requested data */ return l2p_page_get_offset(baton, page, offsets, sub_items, result_pool); } /* Data request structure used by l2p_page_table_access_func. */ typedef struct l2p_page_table_baton_t { /* revision for which to read the page table */ svn_revnum_t revision; /* page table entries (of type l2p_page_table_entry_t). * Must be created by caller and will be filled by callee. */ apr_array_header_t *pages; } l2p_page_table_baton_t; /* Implement svn_cache__partial_getter_func_t: copy the data requested in * l2p_page_baton_t *BATON from l2p_page_t *DATA into BATON->PAGES and *OUT. */ static svn_error_t * l2p_page_table_access_func(void **out, const void *data, apr_size_t data_len, void *baton, apr_pool_t *result_pool) { /* resolve in-cache pointers */ l2p_page_table_baton_t *table_baton = baton; const l2p_header_t *header = (const l2p_header_t *)data; const l2p_page_table_entry_t *page_table = svn_temp_deserializer__ptr(header, (const void *const *)&header->page_table); const apr_size_t *page_table_index = svn_temp_deserializer__ptr(header, (const void *const *)&header->page_table_index); /* copy the revision's page table into BATON */ apr_size_t rel_revision = table_baton->revision - header->first_revision; if (rel_revision < header->revision_count) { const l2p_page_table_entry_t *entry = page_table + page_table_index[rel_revision]; const l2p_page_table_entry_t *last_entry = page_table + page_table_index[rel_revision + 1]; for (; entry < last_entry; ++entry) APR_ARRAY_PUSH(table_baton->pages, l2p_page_table_entry_t) = *entry; } /* set output as a courtesy to the caller */ *out = table_baton->pages; return SVN_NO_ERROR; } /* Read the l2p index page table for REVISION in FS from cache and return * it in PAGES. The later must be provided by the caller (and can be * re-used); existing entries will be removed before writing the result. * If the data cannot be found in the cache, the result will be empty * (it never can be empty for a valid REVISION if the data is cached). * Use the info from REV_FILE to determine pack / rev file properties. * Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * get_l2p_page_table(apr_array_header_t *pages, svn_fs_t *fs, svn_revnum_t revision, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; svn_boolean_t is_cached = FALSE; l2p_page_table_baton_t baton; svn_fs_x__pair_cache_key_t key; key.revision = base_revision(fs, revision); key.second = svn_fs_x__is_packed_rev(fs, revision); apr_array_clear(pages); baton.revision = revision; baton.pages = pages; SVN_ERR(svn_cache__get_partial((void**)&pages, &is_cached, ffd->l2p_header_cache, &key, l2p_page_table_access_func, &baton, scratch_pool)); return SVN_NO_ERROR; } /* Utility function. Read the l2p index pages for REVISION in FS from * STREAM and put them into the cache. Skip page number EXLCUDED_PAGE_NO * (use -1 for 'skip none') and pages outside the MIN_OFFSET, MAX_OFFSET * range in the l2p index file. The index is being identified by * FIRST_REVISION. PAGES is a scratch container provided by the caller. * SCRATCH_POOL is used for temporary allocations. * * This function may be a no-op if the header cache lookup fails / misses. */ static svn_error_t * prefetch_l2p_pages(svn_boolean_t *end, svn_fs_t *fs, svn_fs_x__revision_file_t *rev_file, svn_revnum_t first_revision, svn_revnum_t revision, apr_array_header_t *pages, int exlcuded_page_no, apr_off_t min_offset, apr_off_t max_offset, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; int i; apr_pool_t *iterpool; svn_fs_x__page_cache_key_t key = { 0 }; /* Parameter check. */ if (min_offset < 0) min_offset = 0; if (max_offset <= 0) { /* Nothing to do */ *end = TRUE; return SVN_NO_ERROR; } /* get the page table for REVISION from cache */ *end = FALSE; SVN_ERR(get_l2p_page_table(pages, fs, revision, scratch_pool)); if (pages->nelts == 0) { /* not found -> we can't continue without hitting the disk again */ *end = TRUE; return SVN_NO_ERROR; } /* prefetch pages individually until all are done or we found one in * the cache */ iterpool = svn_pool_create(scratch_pool); assert(revision <= APR_UINT32_MAX); key.revision = (apr_uint32_t)revision; key.is_packed = svn_fs_x__is_packed_rev(fs, revision); for (i = 0; i < pages->nelts && !*end; ++i) { svn_boolean_t is_cached; l2p_page_table_entry_t *entry = &APR_ARRAY_IDX(pages, i, l2p_page_table_entry_t); svn_pool_clear(iterpool); if (i == exlcuded_page_no) continue; /* skip pages outside the specified index file range */ if ( entry->offset < (apr_uint64_t)min_offset || entry->offset + entry->size > (apr_uint64_t)max_offset) { *end = TRUE; continue; } /* page already in cache? */ key.page = i; SVN_ERR(svn_cache__has_key(&is_cached, ffd->l2p_page_cache, &key, iterpool)); if (!is_cached) { /* no in cache -> read from stream (data already buffered in APR) * and cache the result */ l2p_page_t *page = NULL; SVN_ERR(get_l2p_page(&page, rev_file, fs, first_revision, entry, iterpool)); SVN_ERR(svn_cache__set(ffd->l2p_page_cache, &key, page, iterpool)); } } svn_pool_destroy(iterpool); return SVN_NO_ERROR; } /* Using the log-to-phys indexes in FS, find the absolute offset in the * rev file for (REVISION, ITEM_INDEX) and return it in *OFFSET. * Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * l2p_index_lookup(apr_off_t *offset, apr_uint32_t *sub_item, svn_fs_t *fs, svn_fs_x__revision_file_t *rev_file, svn_revnum_t revision, apr_uint64_t item_index, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; l2p_page_info_baton_t info_baton; l2p_page_baton_t page_baton; l2p_page_t *page = NULL; svn_fs_x__page_cache_key_t key = { 0 }; svn_boolean_t is_cached = FALSE; void *dummy = NULL; /* read index master data structure and extract the info required to * access the l2p index page for (REVISION,ITEM_INDEX)*/ info_baton.revision = revision; info_baton.item_index = item_index; SVN_ERR(get_l2p_page_info(&info_baton, rev_file, fs, scratch_pool)); /* try to find the page in the cache and get the OFFSET from it */ page_baton.revision = revision; page_baton.item_index = item_index; page_baton.page_offset = info_baton.page_offset; assert(revision <= APR_UINT32_MAX); key.revision = (apr_uint32_t)revision; key.is_packed = svn_fs_x__is_packed_rev(fs, revision); key.page = info_baton.page_no; SVN_ERR(svn_cache__get_partial(&dummy, &is_cached, ffd->l2p_page_cache, &key, l2p_page_access_func, &page_baton, scratch_pool)); if (!is_cached) { /* we need to read the info from disk (might already be in the * APR file buffer, though) */ apr_array_header_t *pages; svn_revnum_t prefetch_revision; svn_revnum_t last_revision = info_baton.first_revision + svn_fs_x__pack_size(fs, info_baton.first_revision); apr_pool_t *iterpool = svn_pool_create(scratch_pool); svn_boolean_t end; apr_off_t max_offset = APR_ALIGN(info_baton.entry.offset + info_baton.entry.size, ffd->block_size); apr_off_t min_offset = max_offset - ffd->block_size; /* read the relevant page */ SVN_ERR(get_l2p_page(&page, rev_file, fs, info_baton.first_revision, &info_baton.entry, scratch_pool)); /* cache the page and extract the result we need */ SVN_ERR(svn_cache__set(ffd->l2p_page_cache, &key, page, scratch_pool)); SVN_ERR(l2p_page_get_offset(&page_baton, page, page->offsets, page->sub_items, scratch_pool)); /* prefetch pages from following and preceding revisions */ pages = apr_array_make(scratch_pool, 16, sizeof(l2p_page_table_entry_t)); end = FALSE; for (prefetch_revision = revision; prefetch_revision < last_revision && !end; ++prefetch_revision) { int excluded_page_no = prefetch_revision == revision ? info_baton.page_no : -1; svn_pool_clear(iterpool); SVN_ERR(prefetch_l2p_pages(&end, fs, rev_file, info_baton.first_revision, prefetch_revision, pages, excluded_page_no, min_offset, max_offset, iterpool)); } end = FALSE; for (prefetch_revision = revision-1; prefetch_revision >= info_baton.first_revision && !end; --prefetch_revision) { svn_pool_clear(iterpool); SVN_ERR(prefetch_l2p_pages(&end, fs, rev_file, info_baton.first_revision, prefetch_revision, pages, -1, min_offset, max_offset, iterpool)); } svn_pool_destroy(iterpool); } *offset = page_baton.offset; *sub_item = page_baton.sub_item; return SVN_NO_ERROR; } /* Using the log-to-phys proto index in transaction TXN_ID in FS, find the * absolute offset in the proto rev file for the given ITEM_INDEX and return * it in *OFFSET. Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * l2p_proto_index_lookup(apr_off_t *offset, apr_uint32_t *sub_item, svn_fs_t *fs, svn_fs_x__txn_id_t txn_id, apr_uint64_t item_index, apr_pool_t *scratch_pool) { svn_boolean_t eof = FALSE; apr_file_t *file = NULL; SVN_ERR(svn_io_file_open(&file, svn_fs_x__path_l2p_proto_index(fs, txn_id, scratch_pool), APR_READ | APR_BUFFERED, APR_OS_DEFAULT, scratch_pool)); /* process all entries until we fail due to EOF */ *offset = -1; while (!eof) { l2p_proto_entry_t entry; /* (attempt to) read the next entry from the source */ SVN_ERR(read_l2p_entry_from_proto_index(file, &entry, &eof, scratch_pool)); /* handle new revision */ if (!eof && entry.item_index == item_index) { *offset = (apr_off_t)entry.offset - 1; *sub_item = entry.sub_item; break; } } SVN_ERR(svn_io_file_close(file, scratch_pool)); return SVN_NO_ERROR; } svn_error_t * svn_fs_x__l2p_get_max_ids(apr_array_header_t **max_ids, svn_fs_t *fs, svn_revnum_t start_rev, apr_size_t count, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { l2p_header_t *header = NULL; svn_revnum_t revision; svn_revnum_t last_rev = (svn_revnum_t)(start_rev + count); svn_fs_x__revision_file_t *rev_file; apr_pool_t *header_pool = svn_pool_create(scratch_pool); /* read index master data structure for the index covering START_REV */ SVN_ERR(svn_fs_x__open_pack_or_rev_file(&rev_file, fs, start_rev, header_pool, header_pool)); SVN_ERR(get_l2p_header(&header, rev_file, fs, start_rev, header_pool, header_pool)); SVN_ERR(svn_fs_x__close_revision_file(rev_file)); /* Determine the length of the item index list for each rev. * Read new index headers as required. */ *max_ids = apr_array_make(result_pool, (int)count, sizeof(apr_uint64_t)); for (revision = start_rev; revision < last_rev; ++revision) { apr_uint64_t full_page_count; apr_uint64_t item_count; apr_size_t first_page_index, last_page_index; if (revision >= header->first_revision + header->revision_count) { /* need to read the next index. Clear up memory used for the * previous one. Note that intermittent pack runs do not change * the number of items in a revision, i.e. there is no consistency * issue here. */ svn_pool_clear(header_pool); SVN_ERR(svn_fs_x__open_pack_or_rev_file(&rev_file, fs, revision, header_pool, header_pool)); SVN_ERR(get_l2p_header(&header, rev_file, fs, revision, header_pool, header_pool)); SVN_ERR(svn_fs_x__close_revision_file(rev_file)); } /* in a revision with N index pages, the first N-1 index pages are * "full", i.e. contain HEADER->PAGE_SIZE entries */ first_page_index = header->page_table_index[revision - header->first_revision]; last_page_index = header->page_table_index[revision - header->first_revision + 1]; full_page_count = last_page_index - first_page_index - 1; item_count = full_page_count * header->page_size + header->page_table[last_page_index - 1].entry_count; APR_ARRAY_PUSH(*max_ids, apr_uint64_t) = item_count; } svn_pool_destroy(header_pool); return SVN_NO_ERROR; } /* * phys-to-log index */ svn_fs_x__p2l_entry_t * svn_fs_x__p2l_entry_dup(const svn_fs_x__p2l_entry_t *entry, apr_pool_t *result_pool) { svn_fs_x__p2l_entry_t *new_entry = apr_pmemdup(result_pool, entry, sizeof(*new_entry)); if (new_entry->item_count) new_entry->items = apr_pmemdup(result_pool, entry->items, entry->item_count * sizeof(*entry->items)); return new_entry; } /* * phys-to-log index */ svn_error_t * svn_fs_x__p2l_proto_index_open(apr_file_t **proto_index, const char *file_name, apr_pool_t *result_pool) { SVN_ERR(svn_io_file_open(proto_index, file_name, APR_READ | APR_WRITE | APR_CREATE | APR_APPEND | APR_BUFFERED, APR_OS_DEFAULT, result_pool)); return SVN_NO_ERROR; } svn_error_t * svn_fs_x__p2l_proto_index_add_entry(apr_file_t *proto_index, const svn_fs_x__p2l_entry_t *entry, apr_pool_t *scratch_pool) { apr_uint64_t revision; apr_int32_t i; /* Make sure all signed elements of ENTRY have non-negative values. * * For file offsets and sizes, this is a given as we use them to describe * absolute positions and sizes. For revisions, SVN_INVALID_REVNUM is * valid, hence we have to shift it by 1. */ SVN_ERR_ASSERT(entry->offset >= 0); SVN_ERR_ASSERT(entry->size >= 0); /* Now, all values will nicely convert to uint64. */ /* Make sure to keep P2L_PROTO_INDEX_ENTRY_SIZE consistent with this: */ SVN_ERR(write_uint64_to_proto_index(proto_index, entry->offset, scratch_pool)); SVN_ERR(write_uint64_to_proto_index(proto_index, entry->size, scratch_pool)); SVN_ERR(write_uint64_to_proto_index(proto_index, entry->type, scratch_pool)); SVN_ERR(write_uint64_to_proto_index(proto_index, entry->fnv1_checksum, scratch_pool)); SVN_ERR(write_uint64_to_proto_index(proto_index, entry->item_count, scratch_pool)); /* Add sub-items. */ for (i = 0; i < entry->item_count; ++i) { const svn_fs_x__id_t *sub_item = &entry->items[i]; /* Make sure all signed elements of ENTRY have non-negative values. * * For file offsets and sizes, this is a given as we use them to * describe absolute positions and sizes. For revisions, * SVN_INVALID_REVNUM is valid, hence we have to shift it by 1. */ SVN_ERR_ASSERT( sub_item->change_set >= 0 || sub_item->change_set == SVN_INVALID_REVNUM); /* Write sub- record. */ revision = sub_item->change_set == SVN_INVALID_REVNUM ? 0 : ((apr_uint64_t)sub_item->change_set + 1); SVN_ERR(write_uint64_to_proto_index(proto_index, revision, scratch_pool)); SVN_ERR(write_uint64_to_proto_index(proto_index, sub_item->number, scratch_pool)); } /* Add trailer: rev / pack file offset of the next item */ SVN_ERR(write_uint64_to_proto_index(proto_index, entry->offset + entry->size, scratch_pool)); return SVN_NO_ERROR; } /* Read *ENTRY from log-to-phys PROTO_INDEX file and indicate end-of-file * in *EOF, or error out in that case if EOF is NULL. *ENTRY is in an * undefined state if an end-of-file occurred. * Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * read_p2l_entry_from_proto_index(apr_file_t *proto_index, svn_fs_x__p2l_entry_t *entry, svn_boolean_t *eof, apr_pool_t *scratch_pool) { SVN_ERR(read_off_t_from_proto_index(proto_index, &entry->offset, eof, scratch_pool)); SVN_ERR(read_off_t_from_proto_index(proto_index, &entry->size, eof, scratch_pool)); SVN_ERR(read_uint32_from_proto_index(proto_index, &entry->type, eof, scratch_pool)); SVN_ERR(read_uint32_from_proto_index(proto_index, &entry->fnv1_checksum, eof, scratch_pool)); SVN_ERR(read_uint32_from_proto_index(proto_index, &entry->item_count, eof, scratch_pool)); return SVN_NO_ERROR; } static svn_error_t * read_p2l_sub_items_from_proto_index(apr_file_t *proto_index, svn_fs_x__p2l_entry_t *entry, svn_boolean_t *eof, apr_pool_t *scratch_pool) { apr_int32_t i; for (i = 0; i < entry->item_count; ++i) { apr_uint64_t revision; svn_fs_x__id_t *sub_item = &entry->items[i]; SVN_ERR(read_uint64_from_proto_index(proto_index, &revision, eof, scratch_pool)); SVN_ERR(read_uint64_from_proto_index(proto_index, &sub_item->number, eof, scratch_pool)); /* Do the inverse REVSION number conversion (see * svn_fs_x__p2l_proto_index_add_entry), if we actually read a * complete record. */ if (!eof || !*eof) { /* Be careful with the arithmetics here (overflows and wrap-around): */ if (revision > 0 && revision - 1 > LONG_MAX) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW, NULL, _("Revision 0x%s too large, max = 0x%s"), apr_psprintf(scratch_pool, "%" APR_UINT64_T_FMT, revision), apr_psprintf(scratch_pool, "%" APR_UINT64_T_FMT, (apr_uint64_t)LONG_MAX)); /* Shortening conversion from unsigned to signed int is well- * defined and not lossy in C because the value can be represented * in the target type. Also, cast to 'long' instead of * 'svn_revnum_t' here to provoke a compiler warning if those * types should differ and we would need to change the overflow * checking logic. */ sub_item->change_set = revision == 0 ? SVN_INVALID_REVNUM : (long)(revision - 1); } } return SVN_NO_ERROR; } svn_error_t * svn_fs_x__p2l_proto_index_next_offset(apr_off_t *next_offset, apr_file_t *proto_index, apr_pool_t *scratch_pool) { apr_off_t offset = 0; /* Empty index file? */ SVN_ERR(svn_io_file_seek(proto_index, APR_END, &offset, scratch_pool)); if (offset == 0) { *next_offset = 0; } else { /* The last 64 bits contain the value we are looking for. */ offset -= sizeof(apr_uint64_t); SVN_ERR(svn_io_file_seek(proto_index, APR_SET, &offset, scratch_pool)); SVN_ERR(read_off_t_from_proto_index(proto_index, next_offset, NULL, scratch_pool)); } return SVN_NO_ERROR; } svn_error_t * svn_fs_x__p2l_index_append(svn_checksum_t **checksum, svn_fs_t *fs, apr_file_t *index_file, const char *proto_file_name, svn_revnum_t revision, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; apr_uint64_t page_size = ffd->p2l_page_size; apr_file_t *proto_index = NULL; svn_stream_t *stream; int i; apr_uint32_t sub_item; svn_boolean_t eof = FALSE; unsigned char encoded[ENCODED_INT_LENGTH]; apr_uint64_t last_entry_end = 0; apr_uint64_t last_page_end = 0; apr_size_t last_buffer_size = 0; /* byte offset in the spill buffer at the begin of the current revision */ apr_uint64_t file_size = 0; /* temporary data structures that collect the data which will be moved to the target file in a second step */ apr_pool_t *local_pool = svn_pool_create(scratch_pool); apr_array_header_t *table_sizes = apr_array_make(local_pool, 16, sizeof(apr_uint64_t)); /* 64k blocks, spill after 16MB */ svn_spillbuf_t *buffer = svn_spillbuf__create(0x10000, 0x1000000, local_pool); /* for loop temps ... */ apr_pool_t *iterpool = svn_pool_create(scratch_pool); /* start at the beginning of the source file */ SVN_ERR(svn_io_file_open(&proto_index, proto_file_name, APR_READ | APR_CREATE | APR_BUFFERED, APR_OS_DEFAULT, local_pool)); /* process all entries until we fail due to EOF */ while (!eof) { svn_fs_x__p2l_entry_t entry; apr_uint64_t entry_end; svn_boolean_t new_page = svn_spillbuf__get_size(buffer) == 0; svn_revnum_t last_revision = revision; apr_uint64_t last_number = 0; svn_pool_clear(iterpool); /* (attempt to) read the next entry from the source */ SVN_ERR(read_p2l_entry_from_proto_index(proto_index, &entry, &eof, iterpool)); if (entry.item_count && !eof) { entry.items = apr_palloc(iterpool, entry.item_count * sizeof(*entry.items)); SVN_ERR(read_p2l_sub_items_from_proto_index(proto_index, &entry, &eof, iterpool)); } /* Read entry trailer. However, we won't need its content. */ if (!eof) { apr_uint64_t trailer; SVN_ERR(read_uint64_from_proto_index(proto_index, &trailer, &eof, scratch_pool)); } /* "unused" (and usually non-existent) section to cover the offsets at the end the of the last page. */ if (eof) { file_size = last_entry_end; entry.offset = last_entry_end; entry.size = APR_ALIGN(entry.offset, page_size) - entry.offset; entry.type = SVN_FS_X__ITEM_TYPE_UNUSED; entry.fnv1_checksum = 0; entry.item_count = 0; entry.items = NULL; } for (sub_item = 0; sub_item < entry.item_count; ++sub_item) if (entry.items[sub_item].change_set == SVN_FS_X__INVALID_CHANGE_SET) entry.items[sub_item].change_set = svn_fs_x__change_set_by_rev(revision); /* end pages if entry is extending beyond their boundaries */ entry_end = entry.offset + entry.size; while (entry_end - last_page_end > page_size) { apr_uint64_t buffer_size = svn_spillbuf__get_size(buffer); APR_ARRAY_PUSH(table_sizes, apr_uint64_t) = buffer_size - last_buffer_size; last_buffer_size = buffer_size; last_page_end += page_size; new_page = TRUE; } /* this entry starts a new table -> store its offset (all following entries in the same table will store sizes only) */ if (new_page) { SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_uint(encoded, entry.offset), iterpool)); last_revision = revision; } /* write simple item / container entry */ SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_uint(encoded, entry.size), iterpool)); SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_uint(encoded, entry.type + entry.item_count * 16), iterpool)); SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_uint(encoded, entry.fnv1_checksum), iterpool)); /* container contents (only one for non-container items) */ for (sub_item = 0; sub_item < entry.item_count; ++sub_item) { svn_revnum_t item_rev = svn_fs_x__get_revnum(entry.items[sub_item].change_set); apr_int64_t diff = item_rev - last_revision; SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_int(encoded, diff), iterpool)); last_revision = item_rev; } for (sub_item = 0; sub_item < entry.item_count; ++sub_item) { apr_int64_t diff = entry.items[sub_item].number - last_number; SVN_ERR(svn_spillbuf__write(buffer, (const char *)encoded, encode_int(encoded, diff), iterpool)); last_number = entry.items[sub_item].number; } last_entry_end = entry_end; } /* close the source file */ SVN_ERR(svn_io_file_close(proto_index, local_pool)); /* store length of last table */ APR_ARRAY_PUSH(table_sizes, apr_uint64_t) = svn_spillbuf__get_size(buffer) - last_buffer_size; /* Open target stream. */ stream = svn_stream_checksummed2(svn_stream_from_aprfile2(index_file, TRUE, local_pool), NULL, checksum, svn_checksum_md5, FALSE, result_pool); /* write the start revision, file size and page size */ SVN_ERR(svn_stream_puts(stream, P2L_STREAM_PREFIX)); SVN_ERR(stream_write_encoded(stream, revision)); SVN_ERR(stream_write_encoded(stream, file_size)); SVN_ERR(stream_write_encoded(stream, page_size)); /* write the page table (actually, the sizes of each page description) */ SVN_ERR(stream_write_encoded(stream, table_sizes->nelts)); for (i = 0; i < table_sizes->nelts; ++i) { apr_uint64_t value = APR_ARRAY_IDX(table_sizes, i, apr_uint64_t); SVN_ERR(stream_write_encoded(stream, value)); } /* append page contents and implicitly close STREAM */ SVN_ERR(svn_stream_copy3(svn_stream__from_spillbuf(buffer, local_pool), stream, NULL, NULL, local_pool)); svn_pool_destroy(iterpool); svn_pool_destroy(local_pool); return SVN_NO_ERROR; } /* If REV_FILE->P2L_STREAM is NULL, create a new stream for the phys-to-log * index for REVISION in FS using the rev / pack file provided by REV_FILE. */ static svn_error_t * auto_open_p2l_index(svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t revision) { if (rev_file->p2l_stream == NULL) { svn_fs_x__data_t *ffd = fs->fsap_data; SVN_ERR(svn_fs_x__auto_read_footer(rev_file)); SVN_ERR(packed_stream_open(&rev_file->p2l_stream, rev_file->file, rev_file->p2l_offset, rev_file->footer_offset, P2L_STREAM_PREFIX, (apr_size_t)ffd->block_size, rev_file->pool, rev_file->pool)); } return SVN_NO_ERROR; } /* Data structure that describes which p2l page info shall be extracted * from the cache and contains the fields that receive the result. */ typedef struct p2l_page_info_baton_t { /* input variables */ /* revision identifying the index file */ svn_revnum_t revision; /* offset within the page in rev / pack file */ apr_off_t offset; /* output variables */ /* page containing OFFSET */ apr_size_t page_no; /* first revision in this p2l index */ svn_revnum_t first_revision; /* offset within the p2l index file describing this page */ apr_off_t start_offset; /* offset within the p2l index file describing the following page */ apr_off_t next_offset; /* PAGE_NO * PAGE_SIZE (if <= OFFSET) */ apr_off_t page_start; /* total number of pages indexed */ apr_size_t page_count; /* size of each page in pack / rev file */ apr_uint64_t page_size; } p2l_page_info_baton_t; /* From HEADER and the list of all OFFSETS, fill BATON with the page info * requested by BATON->OFFSET. */ static void p2l_page_info_copy(p2l_page_info_baton_t *baton, const p2l_header_t *header, const apr_off_t *offsets) { /* if the requested offset is out of bounds, return info for * a zero-sized empty page right behind the last page. */ if (baton->offset / header->page_size < header->page_count) { /* This cast is safe because the value is < header->page_count. */ baton->page_no = (apr_size_t)(baton->offset / header->page_size); baton->start_offset = offsets[baton->page_no]; baton->next_offset = offsets[baton->page_no + 1]; baton->page_size = header->page_size; } else { /* Beyond the last page. */ baton->page_no = header->page_count; baton->start_offset = offsets[baton->page_no]; baton->next_offset = offsets[baton->page_no]; baton->page_size = 0; } baton->first_revision = header->first_revision; baton->page_start = (apr_off_t)(header->page_size * baton->page_no); baton->page_count = header->page_count; } /* Implement svn_cache__partial_getter_func_t: extract the p2l page info * requested by BATON and return it in BATON. */ static svn_error_t * p2l_page_info_func(void **out, const void *data, apr_size_t data_len, void *baton, apr_pool_t *result_pool) { /* all the pointers to cached data we need */ const p2l_header_t *header = data; const apr_off_t *offsets = svn_temp_deserializer__ptr(header, (const void *const *)&header->offsets); /* copy data from cache to BATON */ p2l_page_info_copy(baton, header, offsets); return SVN_NO_ERROR; } /* Read the header data structure of the phys-to-log index for REVISION in * FS and return it in *HEADER, allocated in RESULT_POOL. Use REV_FILE to * access on-disk data. Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * get_p2l_header(p2l_header_t **header, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t revision, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; apr_uint64_t value; apr_size_t i; apr_off_t offset; p2l_header_t *result; svn_boolean_t is_cached = FALSE; /* look for the header data in our cache */ svn_fs_x__pair_cache_key_t key; key.revision = rev_file->start_revision; key.second = rev_file->is_packed; SVN_ERR(svn_cache__get((void**)header, &is_cached, ffd->p2l_header_cache, &key, result_pool)); if (is_cached) return SVN_NO_ERROR; /* not found -> must read it from disk. * Open index file or position read pointer to the begin of the file */ SVN_ERR(auto_open_p2l_index(rev_file, fs, key.revision)); packed_stream_seek(rev_file->p2l_stream, 0); /* allocate result data structure */ result = apr_pcalloc(result_pool, sizeof(*result)); /* Read table sizes, check them for plausibility and allocate page array. */ SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream)); result->first_revision = (svn_revnum_t)value; if (result->first_revision != rev_file->start_revision) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Index rev / pack file revision numbers do not match")); SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream)); result->file_size = value; if (result->file_size != (apr_uint64_t)rev_file->l2p_offset) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Index offset and rev / pack file size do not match")); SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream)); result->page_size = value; if (!result->page_size || (result->page_size & (result->page_size - 1))) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("P2L index page size is not a power of two")); SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream)); result->page_count = (apr_size_t)value; if (result->page_count != (result->file_size - 1) / result->page_size + 1) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("P2L page count does not match rev / pack file size")); result->offsets = apr_pcalloc(result_pool, (result->page_count + 1) * sizeof(*result->offsets)); /* read page sizes and derive page description offsets from them */ result->offsets[0] = 0; for (i = 0; i < result->page_count; ++i) { SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream)); result->offsets[i+1] = result->offsets[i] + (apr_off_t)value; } /* correct the offset values */ offset = packed_stream_offset(rev_file->p2l_stream); for (i = 0; i <= result->page_count; ++i) result->offsets[i] += offset; /* cache the header data */ SVN_ERR(svn_cache__set(ffd->p2l_header_cache, &key, result, scratch_pool)); /* return the result */ *header = result; return SVN_NO_ERROR; } /* Read the header data structure of the phys-to-log index for revision * BATON->REVISION in FS. Return in *BATON all info relevant to read the * index page for the rev / pack file offset BATON->OFFSET. Use REV_FILE * to access on-disk data. Use SCRATCH_POOL for temporary allocations. */ static svn_error_t * get_p2l_page_info(p2l_page_info_baton_t *baton, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; p2l_header_t *header; svn_boolean_t is_cached = FALSE; void *dummy = NULL; /* look for the header data in our cache */ svn_fs_x__pair_cache_key_t key; key.revision = base_revision(fs, baton->revision); key.second = svn_fs_x__is_packed_rev(fs, baton->revision); SVN_ERR(svn_cache__get_partial(&dummy, &is_cached, ffd->p2l_header_cache, &key, p2l_page_info_func, baton, scratch_pool)); if (is_cached) return SVN_NO_ERROR; SVN_ERR(get_p2l_header(&header, rev_file, fs, baton->revision, scratch_pool, scratch_pool)); /* copy the requested info into *BATON */ p2l_page_info_copy(baton, header, header->offsets); return SVN_NO_ERROR; } /* Read a mapping entry from the phys-to-log index STREAM and append it to * RESULT. *ITEM_INDEX contains the phys offset for the entry and will * be moved forward by the size of entry. */ static svn_error_t * read_entry(svn_fs_x__packed_number_stream_t *stream, apr_off_t *item_offset, svn_revnum_t revision, apr_array_header_t *result) { apr_uint64_t value; apr_uint64_t number = 0; apr_uint32_t sub_item; svn_fs_x__p2l_entry_t entry; entry.offset = *item_offset; SVN_ERR(packed_stream_get(&value, stream)); entry.size = (apr_off_t)value; SVN_ERR(packed_stream_get(&value, stream)); entry.type = (int)value % 16; entry.item_count = (apr_uint32_t)(value / 16); /* Verify item type. */ if (entry.type > SVN_FS_X__ITEM_TYPE_REPS_CONT) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Invalid item type in P2L index")); SVN_ERR(packed_stream_get(&value, stream)); entry.fnv1_checksum = (apr_uint32_t)value; /* Truncating the checksum to 32 bits may have hidden random data in the * unused extra bits of the on-disk representation (7/8 bit representation * uses 5 bytes on disk for the 32 bit value, leaving 3 bits unused). */ if (value > APR_UINT32_MAX) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Invalid FNV1 checksum in P2L index")); /* Some of the index data for empty rev / pack file sections will not be * used during normal operation. Thus, we have strict rules for the * contents of those unused fields. */ if (entry.type == SVN_FS_X__ITEM_TYPE_UNUSED) if ( entry.fnv1_checksum != 0 || entry.item_count != 0) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Unused regions must be empty and have checksum 0")); if (entry.item_count == 0) { entry.items = NULL; } else { entry.items = apr_pcalloc(result->pool, entry.item_count * sizeof(*entry.items)); if ( entry.item_count > 1 && entry.type < SVN_FS_X__ITEM_TYPE_CHANGES_CONT) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Only containers may have more than one sub-item")); for (sub_item = 0; sub_item < entry.item_count; ++sub_item) { SVN_ERR(packed_stream_get(&value, stream)); revision += (svn_revnum_t)(value % 2 ? -1 - value / 2 : value / 2); entry.items[sub_item].change_set = svn_fs_x__change_set_by_rev(revision); } for (sub_item = 0; sub_item < entry.item_count; ++sub_item) { SVN_ERR(packed_stream_get(&value, stream)); number += value % 2 ? -1 - value / 2 : value / 2; entry.items[sub_item].number = number; if ( ( entry.type == SVN_FS_X__ITEM_TYPE_CHANGES || entry.type == SVN_FS_X__ITEM_TYPE_CHANGES_CONT) && number != SVN_FS_X__ITEM_INDEX_CHANGES) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("Changed path list must have item number 1")); } } APR_ARRAY_PUSH(result, svn_fs_x__p2l_entry_t) = entry; *item_offset += entry.size; return SVN_NO_ERROR; } /* Read the phys-to-log mappings for the cluster beginning at rev file * offset PAGE_START from the index for START_REVISION in FS. The data * can be found in the index page beginning at START_OFFSET with the next * page beginning at NEXT_OFFSET. PAGE_SIZE is the L2P index page size. * Return the relevant index entries in *ENTRIES. Use REV_FILE to access * on-disk data. Allocate *ENTRIES in RESULT_POOL. */ static svn_error_t * get_p2l_page(apr_array_header_t **entries, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t start_revision, apr_off_t start_offset, apr_off_t next_offset, apr_off_t page_start, apr_uint64_t page_size, apr_pool_t *result_pool) { apr_uint64_t value; apr_array_header_t *result = apr_array_make(result_pool, 16, sizeof(svn_fs_x__p2l_entry_t)); apr_off_t item_offset; apr_off_t offset; /* open index and navigate to page start */ SVN_ERR(auto_open_p2l_index(rev_file, fs, start_revision)); packed_stream_seek(rev_file->p2l_stream, start_offset); /* read rev file offset of the first page entry (all page entries will * only store their sizes). */ SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream)); item_offset = (apr_off_t)value; /* Special case: empty pages. */ if (start_offset == next_offset) { /* Empty page. This only happens if the first entry of the next page * also covers this page (and possibly more) completely. */ SVN_ERR(read_entry(rev_file->p2l_stream, &item_offset, start_revision, result)); } else { /* Read non-empty page. */ do { SVN_ERR(read_entry(rev_file->p2l_stream, &item_offset, start_revision, result)); offset = packed_stream_offset(rev_file->p2l_stream); } while (offset < next_offset); /* We should now be exactly at the next offset, i.e. the numbers in * the stream cannot overlap into the next page description. */ if (offset != next_offset) return svn_error_create(SVN_ERR_FS_INDEX_CORRUPTION, NULL, _("P2L page description overlaps with next page description")); /* if we haven't covered the cluster end yet, we must read the first * entry of the next page */ if (item_offset < page_start + page_size) { SVN_ERR(packed_stream_get(&value, rev_file->p2l_stream)); item_offset = (apr_off_t)value; SVN_ERR(read_entry(rev_file->p2l_stream, &item_offset, start_revision, result)); } } *entries = result; return SVN_NO_ERROR; } /* If it cannot be found in FS's caches, read the p2l index page selected * by BATON->OFFSET from *STREAM. If the latter is yet to be constructed, * do so in STREAM_POOL. Don't read the page if it precedes MIN_OFFSET. * Set *END to TRUE if the caller should stop refeching. * * *BATON will be updated with the selected page's info and SCRATCH_POOL * will be used for temporary allocations. If the data is alread in the * cache, descrease *LEAKING_BUCKET and increase it otherwise. With that * pattern we will still read all pages from the block even if some of * them survived in the cached. */ static svn_error_t * prefetch_p2l_page(svn_boolean_t *end, int *leaking_bucket, svn_fs_t *fs, svn_fs_x__revision_file_t *rev_file, p2l_page_info_baton_t *baton, apr_off_t min_offset, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; svn_boolean_t already_cached; apr_array_header_t *page; svn_fs_x__page_cache_key_t key = { 0 }; /* fetch the page info */ *end = FALSE; baton->revision = baton->first_revision; SVN_ERR(get_p2l_page_info(baton, rev_file, fs, scratch_pool)); if (baton->start_offset < min_offset) { /* page outside limits -> stop prefetching */ *end = TRUE; return SVN_NO_ERROR; } /* do we have that page in our caches already? */ assert(baton->first_revision <= APR_UINT32_MAX); key.revision = (apr_uint32_t)baton->first_revision; key.is_packed = svn_fs_x__is_packed_rev(fs, baton->first_revision); key.page = baton->page_no; SVN_ERR(svn_cache__has_key(&already_cached, ffd->p2l_page_cache, &key, scratch_pool)); /* yes, already cached */ if (already_cached) { /* stop prefetching if most pages are already cached. */ if (!--*leaking_bucket) *end = TRUE; return SVN_NO_ERROR; } ++*leaking_bucket; /* read from disk */ SVN_ERR(get_p2l_page(&page, rev_file, fs, baton->first_revision, baton->start_offset, baton->next_offset, baton->page_start, baton->page_size, scratch_pool)); /* and put it into our cache */ SVN_ERR(svn_cache__set(ffd->p2l_page_cache, &key, page, scratch_pool)); return SVN_NO_ERROR; } /* Lookup & construct the baton and key information that we will need for * a P2L page cache lookup. We want the page covering OFFSET in the rev / * pack file containing REVSION in FS. Return the results in *PAGE_INFO_P * and *KEY_P. Read data through REV_FILE. Use SCRATCH_POOL for temporary * allocations. */ static svn_error_t * get_p2l_keys(p2l_page_info_baton_t *page_info_p, svn_fs_x__page_cache_key_t *key_p, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t revision, apr_off_t offset, apr_pool_t *scratch_pool) { p2l_page_info_baton_t page_info; /* request info for the index pages that describes the pack / rev file * contents at pack / rev file position OFFSET. */ page_info.offset = offset; page_info.revision = revision; SVN_ERR(get_p2l_page_info(&page_info, rev_file, fs, scratch_pool)); /* if the offset refers to a non-existent page, bail out */ if (page_info.page_count <= page_info.page_no) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL, _("Offset %s too large in revision %ld"), apr_off_t_toa(scratch_pool, offset), revision); /* return results */ if (page_info_p) *page_info_p = page_info; /* construct cache key */ if (key_p) { svn_fs_x__page_cache_key_t key = { 0 }; assert(page_info.first_revision <= APR_UINT32_MAX); key.revision = (apr_uint32_t)page_info.first_revision; key.is_packed = svn_fs_x__is_packed_rev(fs, revision); key.page = page_info.page_no; *key_p = key; } return SVN_NO_ERROR; } /* qsort-compatible compare function that compares the OFFSET of the * svn_fs_x__p2l_entry_t in *LHS with the apr_off_t in *RHS. */ static int compare_start_p2l_entry(const void *lhs, const void *rhs) { const svn_fs_x__p2l_entry_t *entry = lhs; apr_off_t start = *(const apr_off_t*)rhs; apr_off_t diff = entry->offset - start; /* restrict result to int */ return diff < 0 ? -1 : (diff == 0 ? 0 : 1); } /* From the PAGE_ENTRIES array of svn_fs_x__p2l_entry_t, ordered * by their OFFSET member, copy all elements overlapping the range * [BLOCK_START, BLOCK_END) to ENTRIES. If RESOLVE_PTR is set, the ITEMS * sub-array in each entry needs to be de-serialized. */ static void append_p2l_entries(apr_array_header_t *entries, apr_array_header_t *page_entries, apr_off_t block_start, apr_off_t block_end, svn_boolean_t resolve_ptr) { const svn_fs_x__p2l_entry_t *entry; int idx = svn_sort__bsearch_lower_bound(page_entries, &block_start, compare_start_p2l_entry); /* start at the first entry that overlaps with BLOCK_START */ if (idx > 0) { entry = &APR_ARRAY_IDX(page_entries, idx - 1, svn_fs_x__p2l_entry_t); if (entry->offset + entry->size > block_start) --idx; } /* copy all entries covering the requested range */ for ( ; idx < page_entries->nelts; ++idx) { svn_fs_x__p2l_entry_t *copy; entry = &APR_ARRAY_IDX(page_entries, idx, svn_fs_x__p2l_entry_t); if (entry->offset >= block_end) break; /* Copy the entry record. */ copy = apr_array_push(entries); *copy = *entry; /* Copy the items of that entries. */ if (entry->item_count) { const svn_fs_x__id_t *items = resolve_ptr ? svn_temp_deserializer__ptr(page_entries->elts, (const void * const *)&entry->items) : entry->items; copy->items = apr_pmemdup(entries->pool, items, entry->item_count * sizeof(*items)); } } } /* Auxilliary struct passed to p2l_entries_func selecting the relevant * data range. */ typedef struct p2l_entries_baton_t { apr_off_t start; apr_off_t end; } p2l_entries_baton_t; /* Implement svn_cache__partial_getter_func_t: extract p2l entries from * the page in DATA which overlap the p2l_entries_baton_t in BATON. * The target array is already provided in *OUT. */ static svn_error_t * p2l_entries_func(void **out, const void *data, apr_size_t data_len, void *baton, apr_pool_t *result_pool) { apr_array_header_t *entries = *(apr_array_header_t **)out; const apr_array_header_t *raw_page = data; p2l_entries_baton_t *block = baton; /* Make PAGE a readable APR array. */ apr_array_header_t page = *raw_page; page.elts = (void *)svn_temp_deserializer__ptr(raw_page, (const void * const *)&raw_page->elts); /* append relevant information to result */ append_p2l_entries(entries, &page, block->start, block->end, TRUE); return SVN_NO_ERROR; } /* Body of svn_fs_x__p2l_index_lookup. However, do a single index page * lookup and append the result to the ENTRIES array provided by the caller. * Use successive calls to cover larger ranges. */ static svn_error_t * p2l_index_lookup(apr_array_header_t *entries, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t revision, apr_off_t block_start, apr_off_t block_end, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; svn_fs_x__page_cache_key_t key; svn_boolean_t is_cached = FALSE; p2l_page_info_baton_t page_info; apr_array_header_t *local_result = entries; /* baton selecting the relevant entries from the one page we access */ p2l_entries_baton_t block; block.start = block_start; block.end = block_end; /* if we requested an empty range, the result would be empty */ SVN_ERR_ASSERT(block_start < block_end); /* look for the fist page of the range in our cache */ SVN_ERR(get_p2l_keys(&page_info, &key, rev_file, fs, revision, block_start, scratch_pool)); SVN_ERR(svn_cache__get_partial((void**)&local_result, &is_cached, ffd->p2l_page_cache, &key, p2l_entries_func, &block, scratch_pool)); if (!is_cached) { svn_boolean_t end; apr_pool_t *iterpool = svn_pool_create(scratch_pool); apr_off_t original_page_start = page_info.page_start; int leaking_bucket = 4; p2l_page_info_baton_t prefetch_info = page_info; apr_array_header_t *page_entries; apr_off_t max_offset = APR_ALIGN(page_info.next_offset, ffd->block_size); apr_off_t min_offset = APR_ALIGN(page_info.start_offset, ffd->block_size) - ffd->block_size; /* Since we read index data in larger chunks, we probably got more * page data than we requested. Parse & cache that until either we * encounter pages already cached or reach the end of the buffer. */ /* pre-fetch preceding pages */ end = FALSE; prefetch_info.offset = original_page_start; while (prefetch_info.offset >= prefetch_info.page_size && !end) { prefetch_info.offset -= prefetch_info.page_size; SVN_ERR(prefetch_p2l_page(&end, &leaking_bucket, fs, rev_file, &prefetch_info, min_offset, iterpool)); svn_pool_clear(iterpool); } /* fetch page from disk and put it into the cache */ SVN_ERR(get_p2l_page(&page_entries, rev_file, fs, page_info.first_revision, page_info.start_offset, page_info.next_offset, page_info.page_start, page_info.page_size, iterpool)); /* The last cache entry must not end beyond the range covered by * this index. The same applies for any subset of entries. */ if (page_entries->nelts) { const svn_fs_x__p2l_entry_t *entry = &APR_ARRAY_IDX(page_entries, page_entries->nelts - 1, svn_fs_x__p2l_entry_t); if ( entry->offset + entry->size > page_info.page_size * page_info.page_count) return svn_error_createf(SVN_ERR_FS_INDEX_OVERFLOW , NULL, _("Last P2L index entry extends beyond " "the last page in revision %ld."), revision); } SVN_ERR(svn_cache__set(ffd->p2l_page_cache, &key, page_entries, iterpool)); /* append relevant information to result */ append_p2l_entries(entries, page_entries, block_start, block_end, FALSE); /* pre-fetch following pages */ end = FALSE; leaking_bucket = 4; prefetch_info = page_info; prefetch_info.offset = original_page_start; while ( prefetch_info.next_offset < max_offset && prefetch_info.page_no + 1 < prefetch_info.page_count && !end) { prefetch_info.offset += prefetch_info.page_size; SVN_ERR(prefetch_p2l_page(&end, &leaking_bucket, fs, rev_file, &prefetch_info, min_offset, iterpool)); svn_pool_clear(iterpool); } svn_pool_destroy(iterpool); } /* We access a valid page (otherwise, we had seen an error in the * get_p2l_keys request). Hence, at least one entry must be found. */ SVN_ERR_ASSERT(entries->nelts > 0); /* Add an "unused" entry if it extends beyond the end of the data file. * Since the index page size might be smaller than the current data * read block size, the trailing "unused" entry in this index may not * fully cover the end of the last block. */ if (page_info.page_no + 1 >= page_info.page_count) { svn_fs_x__p2l_entry_t *entry = &APR_ARRAY_IDX(entries, entries->nelts-1, svn_fs_x__p2l_entry_t); apr_off_t entry_end = entry->offset + entry->size; if (entry_end < block_end) { if (entry->type == SVN_FS_X__ITEM_TYPE_UNUSED) { /* extend the terminal filler */ entry->size = block_end - entry->offset; } else { /* No terminal filler. Add one. */ entry = apr_array_push(entries); entry->offset = entry_end; entry->size = block_end - entry_end; entry->type = SVN_FS_X__ITEM_TYPE_UNUSED; entry->fnv1_checksum = 0; entry->item_count = 0; entry->items = NULL; } } } return SVN_NO_ERROR; } svn_error_t * svn_fs_x__p2l_index_lookup(apr_array_header_t **entries, svn_fs_t *fs, svn_fs_x__revision_file_t *rev_file, svn_revnum_t revision, apr_off_t block_start, apr_off_t block_size, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { apr_off_t block_end = block_start + block_size; /* the receiving container */ int last_count = 0; apr_array_header_t *result = apr_array_make(result_pool, 16, sizeof(svn_fs_x__p2l_entry_t)); /* Fetch entries page-by-page. Since the p2l index is supposed to cover * every single byte in the rev / pack file - even unused sections - * every iteration must result in some progress. */ while (block_start < block_end) { svn_fs_x__p2l_entry_t *entry; SVN_ERR(p2l_index_lookup(result, rev_file, fs, revision, block_start, block_end, scratch_pool)); SVN_ERR_ASSERT(result->nelts > 0); /* continue directly behind last item */ entry = &APR_ARRAY_IDX(result, result->nelts-1, svn_fs_x__p2l_entry_t); block_start = entry->offset + entry->size; /* Some paranoia check. Successive iterations should never return * duplicates but if it did, we might get into trouble later on. */ if (last_count > 0 && last_count < result->nelts) { entry = &APR_ARRAY_IDX(result, last_count - 1, svn_fs_x__p2l_entry_t); SVN_ERR_ASSERT(APR_ARRAY_IDX(result, last_count, svn_fs_x__p2l_entry_t).offset >= entry->offset + entry->size); } last_count = result->nelts; } *entries = result; return SVN_NO_ERROR; } /* compare_fn_t comparing a svn_fs_x__p2l_entry_t at LHS with an offset * RHS. */ static int compare_p2l_entry_offsets(const void *lhs, const void *rhs) { const svn_fs_x__p2l_entry_t *entry = (const svn_fs_x__p2l_entry_t *)lhs; apr_off_t offset = *(const apr_off_t *)rhs; return entry->offset < offset ? -1 : (entry->offset == offset ? 0 : 1); } /* Cached data extraction utility. DATA is a P2L index page, e.g. an APR * array of svn_fs_fs__p2l_entry_t elements. Return the entry for the item, * allocated in RESULT_POOL, starting at OFFSET or NULL if that's not an * the start offset of any item. Use SCRATCH_POOL for temporary allocations. */ static svn_fs_x__p2l_entry_t * get_p2l_entry_from_cached_page(const void *data, apr_off_t offset, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { /* resolve all pointer values of in-cache data */ const apr_array_header_t *page = data; apr_array_header_t *entries = apr_pmemdup(scratch_pool, page, sizeof(*page)); svn_fs_x__p2l_entry_t *entry; entries->elts = (char *)svn_temp_deserializer__ptr(page, (const void *const *)&page->elts); /* search of the offset we want */ entry = svn_sort__array_lookup(entries, &offset, NULL, (int (*)(const void *, const void *))compare_p2l_entry_offsets); /* return it, if it is a perfect match */ if (entry) { svn_fs_x__p2l_entry_t *result = apr_pmemdup(result_pool, entry, sizeof(*result)); result->items = (svn_fs_x__id_t *)svn_temp_deserializer__ptr(entries->elts, (const void *const *)&entry->items); return result; } return NULL; } /* Implements svn_cache__partial_getter_func_t for P2L index pages, copying * the entry for the apr_off_t at BATON into *OUT. *OUT will be NULL if * there is no matching entry in the index page at DATA. */ static svn_error_t * p2l_entry_lookup_func(void **out, const void *data, apr_size_t data_len, void *baton, apr_pool_t *result_pool) { svn_fs_x__p2l_entry_t *entry = get_p2l_entry_from_cached_page(data, *(apr_off_t *)baton, result_pool, result_pool); *out = entry && entry->offset == *(apr_off_t *)baton ? svn_fs_x__p2l_entry_dup(entry, result_pool) : NULL; return SVN_NO_ERROR; } static svn_error_t * p2l_entry_lookup(svn_fs_x__p2l_entry_t **entry_p, svn_fs_x__revision_file_t *rev_file, svn_fs_t *fs, svn_revnum_t revision, apr_off_t offset, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; svn_fs_x__page_cache_key_t key = { 0 }; svn_boolean_t is_cached = FALSE; p2l_page_info_baton_t page_info; /* look for this info in our cache */ SVN_ERR(get_p2l_keys(&page_info, &key, rev_file, fs, revision, offset, scratch_pool)); SVN_ERR(svn_cache__get_partial((void**)entry_p, &is_cached, ffd->p2l_page_cache, &key, p2l_entry_lookup_func, &offset, result_pool)); if (!is_cached) { /* do a standard index lookup. This is will automatically prefetch * data to speed up future lookups. */ apr_array_header_t *entries = apr_array_make(result_pool, 1, sizeof(**entry_p)); SVN_ERR(p2l_index_lookup(entries, rev_file, fs, revision, offset, offset + 1, scratch_pool)); /* Find the entry that we want. */ *entry_p = svn_sort__array_lookup(entries, &offset, NULL, (int (*)(const void *, const void *))compare_p2l_entry_offsets); } return SVN_NO_ERROR; } svn_error_t * svn_fs_x__p2l_entry_lookup(svn_fs_x__p2l_entry_t **entry_p, svn_fs_t *fs, svn_fs_x__revision_file_t *rev_file, svn_revnum_t revision, apr_off_t offset, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { /* look for this info in our cache */ SVN_ERR(p2l_entry_lookup(entry_p, rev_file, fs, revision, offset, result_pool, scratch_pool)); return SVN_NO_ERROR; } /* Baton structure for p2l_item_lookup_func. It describes which sub_item * info shall be returned. */ typedef struct p2l_item_lookup_baton_t { /* file offset to find the P2L index entry for */ apr_off_t offset; /* return the sub-item at this position within that entry */ apr_uint32_t sub_item; } p2l_item_lookup_baton_t; /* Implements svn_cache__partial_getter_func_t for P2L index pages, copying * the svn_fs_x__id_t for the item described 2l_item_lookup_baton_t * *BATON. *OUT will be NULL if there is no matching index entry or the * sub-item is out of range. */ static svn_error_t * p2l_item_lookup_func(void **out, const void *data, apr_size_t data_len, void *baton, apr_pool_t *result_pool) { p2l_item_lookup_baton_t *lookup_baton = baton; svn_fs_x__p2l_entry_t *entry = get_p2l_entry_from_cached_page(data, lookup_baton->offset, result_pool, result_pool); *out = entry && entry->offset == lookup_baton->offset && entry->item_count > lookup_baton->sub_item ? apr_pmemdup(result_pool, entry->items + lookup_baton->sub_item, sizeof(*entry->items)) : NULL; return SVN_NO_ERROR; } svn_error_t * svn_fs_x__p2l_item_lookup(svn_fs_x__id_t **item, svn_fs_t *fs, svn_fs_x__revision_file_t *rev_file, svn_revnum_t revision, apr_off_t offset, apr_uint32_t sub_item, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; svn_fs_x__page_cache_key_t key = { 0 }; svn_boolean_t is_cached = FALSE; p2l_page_info_baton_t page_info; p2l_item_lookup_baton_t baton; *item = NULL; /* look for this info in our cache */ SVN_ERR(get_p2l_keys(&page_info, &key, rev_file, fs, revision, offset, scratch_pool)); baton.offset = offset; baton.sub_item = sub_item; SVN_ERR(svn_cache__get_partial((void**)item, &is_cached, ffd->p2l_page_cache, &key, p2l_item_lookup_func, &baton, result_pool)); if (!is_cached) { /* do a standard index lookup. This is will automatically prefetch * data to speed up future lookups. */ svn_fs_x__p2l_entry_t *entry; SVN_ERR(p2l_entry_lookup(&entry, rev_file, fs, revision, offset, result_pool, scratch_pool)); /* return result */ if (entry && entry->item_count > sub_item) *item = apr_pmemdup(result_pool, entry->items + sub_item, sizeof(**item)); } return SVN_NO_ERROR; } /* Implements svn_cache__partial_getter_func_t for P2L headers, setting *OUT * to the largest the first offset not covered by this P2L index. */ static svn_error_t * p2l_get_max_offset_func(void **out, const void *data, apr_size_t data_len, void *baton, apr_pool_t *result_pool) { const p2l_header_t *header = data; apr_off_t max_offset = header->file_size; *out = apr_pmemdup(result_pool, &max_offset, sizeof(max_offset)); return SVN_NO_ERROR; } svn_error_t * svn_fs_x__p2l_get_max_offset(apr_off_t *offset, svn_fs_t *fs, svn_fs_x__revision_file_t *rev_file, svn_revnum_t revision, apr_pool_t *scratch_pool) { svn_fs_x__data_t *ffd = fs->fsap_data; p2l_header_t *header; svn_boolean_t is_cached = FALSE; apr_off_t *offset_p; /* look for the header data in our cache */ svn_fs_x__pair_cache_key_t key; key.revision = base_revision(fs, revision); key.second = svn_fs_x__is_packed_rev(fs, revision); SVN_ERR(svn_cache__get_partial((void **)&offset_p, &is_cached, ffd->p2l_header_cache, &key, p2l_get_max_offset_func, NULL, scratch_pool)); if (is_cached) { *offset = *offset_p; return SVN_NO_ERROR; } SVN_ERR(get_p2l_header(&header, rev_file, fs, revision, scratch_pool, scratch_pool)); *offset = header->file_size; return SVN_NO_ERROR; } svn_error_t * svn_fs_x__item_offset(apr_off_t *absolute_position, apr_uint32_t *sub_item, svn_fs_t *fs, svn_fs_x__revision_file_t *rev_file, const svn_fs_x__id_t *item_id, apr_pool_t *scratch_pool) { if (svn_fs_x__is_txn(item_id->change_set)) SVN_ERR(l2p_proto_index_lookup(absolute_position, sub_item, fs, svn_fs_x__get_txn_id(item_id->change_set), item_id->number, scratch_pool)); else SVN_ERR(l2p_index_lookup(absolute_position, sub_item, fs, rev_file, svn_fs_x__get_revnum(item_id->change_set), item_id->number, scratch_pool)); return SVN_NO_ERROR; } /* Calculate the FNV1 checksum over the offset range in REV_FILE, covered by * ENTRY. Store the result in ENTRY->FNV1_CHECKSUM. Use SCRATCH_POOL for * temporary allocations. */ static svn_error_t * calc_fnv1(svn_fs_x__p2l_entry_t *entry, svn_fs_x__revision_file_t *rev_file, apr_pool_t *scratch_pool) { unsigned char buffer[4096]; svn_checksum_t *checksum; svn_checksum_ctx_t *context = svn_checksum_ctx_create(svn_checksum_fnv1a_32x4, scratch_pool); apr_off_t size = entry->size; /* Special rules apply to unused sections / items. The data must be a * sequence of NUL bytes (not checked here) and the checksum is fixed to 0. */ if (entry->type == SVN_FS_X__ITEM_TYPE_UNUSED) { entry->fnv1_checksum = 0; return SVN_NO_ERROR; } /* Read the block and feed it to the checksum calculator. */ SVN_ERR(svn_io_file_seek(rev_file->file, APR_SET, &entry->offset, scratch_pool)); while (size > 0) { apr_size_t to_read = size > sizeof(buffer) ? sizeof(buffer) : (apr_size_t)size; SVN_ERR(svn_io_file_read_full2(rev_file->file, buffer, to_read, NULL, NULL, scratch_pool)); SVN_ERR(svn_checksum_update(context, buffer, to_read)); size -= to_read; } /* Store final checksum in ENTRY. */ SVN_ERR(svn_checksum_final(&checksum, context, scratch_pool)); entry->fnv1_checksum = ntohl(*(const apr_uint32_t *)checksum->digest); return SVN_NO_ERROR; } /* * Index (re-)creation utilities. */ svn_error_t * svn_fs_x__p2l_index_from_p2l_entries(const char **protoname, svn_fs_t *fs, svn_fs_x__revision_file_t *rev_file, apr_array_header_t *entries, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { apr_file_t *proto_index; /* Use a subpool for immediate temp file cleanup at the end of this * function. */ apr_pool_t *iterpool = svn_pool_create(scratch_pool); int i; /* Create a proto-index file. */ SVN_ERR(svn_io_open_unique_file3(NULL, protoname, NULL, svn_io_file_del_on_pool_cleanup, result_pool, scratch_pool)); SVN_ERR(svn_fs_x__p2l_proto_index_open(&proto_index, *protoname, scratch_pool)); /* Write ENTRIES to proto-index file and calculate checksums as we go. */ for (i = 0; i < entries->nelts; ++i) { svn_fs_x__p2l_entry_t *entry = APR_ARRAY_IDX(entries, i, svn_fs_x__p2l_entry_t *); svn_pool_clear(iterpool); SVN_ERR(calc_fnv1(entry, rev_file, iterpool)); SVN_ERR(svn_fs_x__p2l_proto_index_add_entry(proto_index, entry, iterpool)); } /* Convert proto-index into final index and move it into position. * Note that REV_FILE contains the start revision of the shard file if it * has been packed while REVISION may be somewhere in the middle. For * non-packed shards, they will have identical values. */ SVN_ERR(svn_io_file_close(proto_index, iterpool)); /* Temp file cleanup. */ svn_pool_destroy(iterpool); return SVN_NO_ERROR; } /* Decorator for svn_fs_x__p2l_entry_t that associates it with a sorted * variant of its ITEMS array. */ typedef struct sub_item_ordered_t { /* ENTRY that got wrapped */ svn_fs_x__p2l_entry_t *entry; /* Array of pointers into ENTRY->ITEMS, sorted by their revision member * _descending_ order. May be NULL if ENTRY->ITEM_COUNT < 2. */ svn_fs_x__id_t **order; } sub_item_ordered_t; /* implements compare_fn_t. Place LHS before RHS, if the latter is younger. * Used to sort sub_item_ordered_t::order */ static int compare_sub_items(const svn_fs_x__id_t * const * lhs, const svn_fs_x__id_t * const * rhs) { return (*lhs)->change_set < (*rhs)->change_set ? 1 : ((*lhs)->change_set > (*rhs)->change_set ? -1 : 0); } /* implements compare_fn_t. Place LHS before RHS, if the latter belongs to * a newer revision. */ static int compare_p2l_info_rev(const sub_item_ordered_t * lhs, const sub_item_ordered_t * rhs) { svn_fs_x__id_t *lhs_part; svn_fs_x__id_t *rhs_part; assert(lhs != rhs); if (lhs->entry->item_count == 0) return rhs->entry->item_count == 0 ? 0 : -1; if (rhs->entry->item_count == 0) return 1; lhs_part = lhs->order ? lhs->order[lhs->entry->item_count - 1] : &lhs->entry->items[0]; rhs_part = rhs->order ? rhs->order[rhs->entry->item_count - 1] : &rhs->entry->items[0]; if (lhs_part->change_set == rhs_part->change_set) return 0; return lhs_part->change_set < rhs_part->change_set ? -1 : 1; } svn_error_t * svn_fs_x__l2p_index_from_p2l_entries(const char **protoname, svn_fs_t *fs, apr_array_header_t *entries, apr_pool_t *result_pool, apr_pool_t *scratch_pool) { apr_file_t *proto_index; /* Use a subpool for immediate temp file cleanup at the end of this * function. */ apr_pool_t *iterpool = svn_pool_create(scratch_pool); svn_revnum_t prev_rev = SVN_INVALID_REVNUM; int i; apr_uint32_t k; svn_priority_queue__t *queue; apr_size_t count = 0; apr_array_header_t *sub_item_orders; /* Create the temporary proto-rev file. */ SVN_ERR(svn_io_open_unique_file3(NULL, protoname, NULL, svn_io_file_del_on_pool_cleanup, result_pool, scratch_pool)); SVN_ERR(svn_fs_x__l2p_proto_index_open(&proto_index, *protoname, scratch_pool)); /* wrap P2L entries such that we have access to the sub-items in revision order. The ENTRY_COUNT member will point to the next item to read+1. */ sub_item_orders = apr_array_make(scratch_pool, entries->nelts, sizeof(sub_item_ordered_t)); sub_item_orders->nelts = entries->nelts; for (i = 0; i < entries->nelts; ++i) { svn_fs_x__p2l_entry_t *entry = APR_ARRAY_IDX(entries, i, svn_fs_x__p2l_entry_t *); sub_item_ordered_t *ordered = &APR_ARRAY_IDX(sub_item_orders, i, sub_item_ordered_t); /* skip unused regions (e.g. padding) */ if (entry->item_count == 0) { --sub_item_orders->nelts; continue; } assert(entry); ordered->entry = entry; count += entry->item_count; if (entry->item_count > 1) { ordered->order = apr_palloc(scratch_pool, sizeof(*ordered->order) * entry->item_count); for (k = 0; k < entry->item_count; ++k) ordered->order[k] = &entry->items[k]; qsort(ordered->order, entry->item_count, sizeof(*ordered->order), (int (*)(const void *, const void *))compare_sub_items); } } /* we need to write the index in ascending revision order */ queue = svn_priority_queue__create (sub_item_orders, (int (*)(const void *, const void *))compare_p2l_info_rev); /* write index entries */ for (i = 0; i < count; ++i) { svn_fs_x__id_t *sub_item; sub_item_ordered_t *ordered = svn_priority_queue__peek(queue); if (ordered->entry->item_count > 0) { /* if there is only one item, we skip the overhead of having an extra array for the item order */ sub_item = ordered->order ? ordered->order[ordered->entry->item_count - 1] : &ordered->entry->items[0]; /* next revision? */ if (prev_rev != svn_fs_x__get_revnum(sub_item->change_set)) { prev_rev = svn_fs_x__get_revnum(sub_item->change_set); SVN_ERR(svn_fs_x__l2p_proto_index_add_revision (proto_index, iterpool)); } /* add entry */ SVN_ERR(svn_fs_x__l2p_proto_index_add_entry (proto_index, ordered->entry->offset, (apr_uint32_t)(sub_item - ordered->entry->items), sub_item->number, iterpool)); /* make ITEM_COUNT point the next sub-item to use+1 */ --ordered->entry->item_count; } /* process remaining sub-items (if any) of that container later */ if (ordered->entry->item_count) svn_priority_queue__update(queue); else svn_priority_queue__pop(queue); /* keep memory usage in check */ if (i % 256 == 0) svn_pool_clear(iterpool); } /* Convert proto-index into final index and move it into position. */ SVN_ERR(svn_io_file_close(proto_index, iterpool)); /* Temp file cleanup. */ svn_pool_destroy(iterpool); return SVN_NO_ERROR; } /* * Standard (de-)serialization functions */ svn_error_t * svn_fs_x__serialize_l2p_header(void **data, apr_size_t *data_len, void *in, apr_pool_t *pool) { l2p_header_t *header = in; svn_temp_serializer__context_t *context; svn_stringbuf_t *serialized; apr_size_t page_count = header->page_table_index[header->revision_count]; apr_size_t page_table_size = page_count * sizeof(*header->page_table); apr_size_t index_size = (header->revision_count + 1) * sizeof(*header->page_table_index); apr_size_t data_size = sizeof(*header) + index_size + page_table_size; /* serialize header and all its elements */ context = svn_temp_serializer__init(header, sizeof(*header), data_size + 32, pool); /* page table index array */ svn_temp_serializer__add_leaf(context, (const void * const *)&header->page_table_index, index_size); /* page table array */ svn_temp_serializer__add_leaf(context, (const void * const *)&header->page_table, page_table_size); /* return the serialized result */ serialized = svn_temp_serializer__get(context); *data = serialized->data; *data_len = serialized->len; return SVN_NO_ERROR; } svn_error_t * svn_fs_x__deserialize_l2p_header(void **out, void *data, apr_size_t data_len, apr_pool_t *pool) { l2p_header_t *header = (l2p_header_t *)data; /* resolve the pointers in the struct */ svn_temp_deserializer__resolve(header, (void**)&header->page_table_index); svn_temp_deserializer__resolve(header, (void**)&header->page_table); /* done */ *out = header; return SVN_NO_ERROR; } svn_error_t * svn_fs_x__serialize_l2p_page(void **data, apr_size_t *data_len, void *in, apr_pool_t *pool) { l2p_page_t *page = in; svn_temp_serializer__context_t *context; svn_stringbuf_t *serialized; apr_size_t of_table_size = page->entry_count * sizeof(*page->offsets); apr_size_t si_table_size = page->entry_count * sizeof(*page->sub_items); /* serialize struct and all its elements */ context = svn_temp_serializer__init(page, sizeof(*page), of_table_size + si_table_size + sizeof(*page) + 32, pool); /* offsets and sub_items arrays */ svn_temp_serializer__add_leaf(context, (const void * const *)&page->offsets, of_table_size); svn_temp_serializer__add_leaf(context, (const void * const *)&page->sub_items, si_table_size); /* return the serialized result */ serialized = svn_temp_serializer__get(context); *data = serialized->data; *data_len = serialized->len; return SVN_NO_ERROR; } svn_error_t * svn_fs_x__deserialize_l2p_page(void **out, void *data, apr_size_t data_len, apr_pool_t *pool) { l2p_page_t *page = data; /* resolve the pointers in the struct */ svn_temp_deserializer__resolve(page, (void**)&page->offsets); svn_temp_deserializer__resolve(page, (void**)&page->sub_items); /* done */ *out = page; return SVN_NO_ERROR; } svn_error_t * svn_fs_x__serialize_p2l_header(void **data, apr_size_t *data_len, void *in, apr_pool_t *pool) { p2l_header_t *header = in; svn_temp_serializer__context_t *context; svn_stringbuf_t *serialized; apr_size_t table_size = (header->page_count + 1) * sizeof(*header->offsets); /* serialize header and all its elements */ context = svn_temp_serializer__init(header, sizeof(*header), table_size + sizeof(*header) + 32, pool); /* offsets array */ svn_temp_serializer__add_leaf(context, (const void * const *)&header->offsets, table_size); /* return the serialized result */ serialized = svn_temp_serializer__get(context); *data = serialized->data; *data_len = serialized->len; return SVN_NO_ERROR; } svn_error_t * svn_fs_x__deserialize_p2l_header(void **out, void *data, apr_size_t data_len, apr_pool_t *pool) { p2l_header_t *header = data; /* resolve the only pointer in the struct */ svn_temp_deserializer__resolve(header, (void**)&header->offsets); /* done */ *out = header; return SVN_NO_ERROR; } svn_error_t * svn_fs_x__serialize_p2l_page(void **data, apr_size_t *data_len, void *in, apr_pool_t *pool) { apr_array_header_t *page = in; svn_temp_serializer__context_t *context; svn_stringbuf_t *serialized; apr_size_t table_size = page->elt_size * page->nelts; svn_fs_x__p2l_entry_t *entries = (svn_fs_x__p2l_entry_t *)page->elts; int i; /* serialize array header and all its elements */ context = svn_temp_serializer__init(page, sizeof(*page), table_size + sizeof(*page) + 32, pool); /* items in the array */ svn_temp_serializer__push(context, (const void * const *)&page->elts, table_size); for (i = 0; i < page->nelts; ++i) svn_temp_serializer__add_leaf(context, (const void * const *)&entries[i].items, entries[i].item_count * sizeof(*entries[i].items)); svn_temp_serializer__pop(context); /* return the serialized result */ serialized = svn_temp_serializer__get(context); *data = serialized->data; *data_len = serialized->len; return SVN_NO_ERROR; } svn_error_t * svn_fs_x__deserialize_p2l_page(void **out, void *data, apr_size_t data_len, apr_pool_t *pool) { apr_array_header_t *page = (apr_array_header_t *)data; svn_fs_x__p2l_entry_t *entries; int i; /* resolve the only pointer in the struct */ svn_temp_deserializer__resolve(page, (void**)&page->elts); /* resolve sub-struct pointers*/ entries = (svn_fs_x__p2l_entry_t *)page->elts; for (i = 0; i < page->nelts; ++i) svn_temp_deserializer__resolve(entries, (void**)&entries[i].items); /* patch up members */ page->pool = pool; page->nalloc = page->nelts; /* done */ *out = page; return SVN_NO_ERROR; }