diff options
Diffstat (limited to 'subversion/libsvn_fs_x/temp_serializer.c')
| -rw-r--r-- | subversion/libsvn_fs_x/temp_serializer.c | 1337 |
1 files changed, 1337 insertions, 0 deletions
diff --git a/subversion/libsvn_fs_x/temp_serializer.c b/subversion/libsvn_fs_x/temp_serializer.c new file mode 100644 index 0000000..65a2c3f --- /dev/null +++ b/subversion/libsvn_fs_x/temp_serializer.c @@ -0,0 +1,1337 @@ +/* temp_serializer.c: serialization functions for caching of FSX structures + * + * ==================================================================== + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + * ==================================================================== + */ + +#include <apr_pools.h> + +#include "svn_pools.h" +#include "svn_hash.h" +#include "svn_sorts.h" +#include "svn_fs.h" + +#include "private/svn_fs_util.h" +#include "private/svn_sorts_private.h" +#include "private/svn_temp_serializer.h" +#include "private/svn_subr_private.h" + +#include "id.h" +#include "temp_serializer.h" +#include "low_level.h" +#include "cached_data.h" + +/* Utility to encode a signed NUMBER into a variable-length sequence of + * 8-bit chars in KEY_BUFFER and return the last writen position. + * + * Numbers will be stored in 7 bits / byte and using byte values above + * 32 (' ') to make them combinable with other string by simply separating + * individual parts with spaces. + */ +static char* +encode_number(apr_int64_t number, char *key_buffer) +{ + /* encode the sign in the first byte */ + if (number < 0) + { + number = -number; + *key_buffer = (char)((number & 63) + ' ' + 65); + } + else + *key_buffer = (char)((number & 63) + ' ' + 1); + number /= 64; + + /* write 7 bits / byte until no significant bits are left */ + while (number) + { + *++key_buffer = (char)((number & 127) + ' ' + 1); + number /= 128; + } + + /* return the last written position */ + return key_buffer; +} + +const char* +svn_fs_x__combine_number_and_string(apr_int64_t number, + const char *string, + apr_pool_t *pool) +{ + apr_size_t len = strlen(string); + + /* number part requires max. 10x7 bits + 1 space. + * Add another 1 for the terminal 0 */ + char *key_buffer = apr_palloc(pool, len + 12); + const char *key = key_buffer; + + /* Prepend the number to the string and separate them by space. No other + * number can result in the same prefix, no other string in the same + * postfix nor can the boundary between them be ambiguous. */ + key_buffer = encode_number(number, key_buffer); + *++key_buffer = ' '; + memcpy(++key_buffer, string, len+1); + + /* return the start of the key */ + return key; +} + +/* Utility function to serialize string S in the given serialization CONTEXT. + */ +static void +serialize_svn_string(svn_temp_serializer__context_t *context, + const svn_string_t * const *s) +{ + const svn_string_t *string = *s; + + /* Nothing to do for NULL string references. */ + if (string == NULL) + return; + + svn_temp_serializer__push(context, + (const void * const *)s, + sizeof(*string)); + + /* the "string" content may actually be arbitrary binary data. + * Thus, we cannot use svn_temp_serializer__add_string. */ + svn_temp_serializer__add_leaf(context, + (const void * const *)&string->data, + string->len + 1); + + /* back to the caller's nesting level */ + svn_temp_serializer__pop(context); +} + +/* Utility function to deserialize the STRING inside the BUFFER. + */ +static void +deserialize_svn_string(void *buffer, svn_string_t **string) +{ + svn_temp_deserializer__resolve(buffer, (void **)string); + if (*string == NULL) + return; + + svn_temp_deserializer__resolve(*string, (void **)&(*string)->data); +} + +/* Utility function to serialize the REPRESENTATION within the given + * serialization CONTEXT. + */ +static void +serialize_representation(svn_temp_serializer__context_t *context, + svn_fs_x__representation_t * const *representation) +{ + const svn_fs_x__representation_t * rep = *representation; + if (rep == NULL) + return; + + /* serialize the representation struct itself */ + svn_temp_serializer__add_leaf(context, + (const void * const *)representation, + sizeof(*rep)); +} + +void +svn_fs_x__serialize_apr_array(svn_temp_serializer__context_t *context, + apr_array_header_t **a) +{ + const apr_array_header_t *array = *a; + + /* Nothing to do for NULL string references. */ + if (array == NULL) + return; + + /* array header struct */ + svn_temp_serializer__push(context, + (const void * const *)a, + sizeof(*array)); + + /* contents */ + svn_temp_serializer__add_leaf(context, + (const void * const *)&array->elts, + (apr_size_t)array->nelts * array->elt_size); + + /* back to the caller's nesting level */ + svn_temp_serializer__pop(context); +} + +void +svn_fs_x__deserialize_apr_array(void *buffer, + apr_array_header_t **array, + apr_pool_t *pool) +{ + svn_temp_deserializer__resolve(buffer, (void **)array); + if (*array == NULL) + return; + + svn_temp_deserializer__resolve(*array, (void **)&(*array)->elts); + (*array)->pool = pool; +} + +/* auxilliary structure representing the content of a directory array */ +typedef struct dir_data_t +{ + /* number of entries in the directory + * (it's int because the directory is an APR array) */ + int count; + + /* number of unused dir entry buckets in the index */ + apr_size_t over_provision; + + /* internal modifying operations counter + * (used to repack data once in a while) */ + apr_size_t operations; + + /* size of the serialization buffer actually used. + * (we will allocate more than we actually need such that we may + * append more data in situ later) */ + apr_size_t len; + + /* reference to the entries */ + svn_fs_x__dirent_t **entries; + + /* size of the serialized entries and don't be too wasteful + * (needed since the entries are no longer in sequence) */ + apr_uint32_t *lengths; +} dir_data_t; + +/* Utility function to serialize the *ENTRY_P into a the given + * serialization CONTEXT. Return the serialized size of the + * dir entry in *LENGTH. + */ +static void +serialize_dir_entry(svn_temp_serializer__context_t *context, + svn_fs_x__dirent_t **entry_p, + apr_uint32_t *length) +{ + svn_fs_x__dirent_t *entry = *entry_p; + apr_size_t initial_length = svn_temp_serializer__get_length(context); + + svn_temp_serializer__push(context, + (const void * const *)entry_p, + sizeof(svn_fs_x__dirent_t)); + + svn_temp_serializer__add_string(context, &entry->name); + + *length = (apr_uint32_t)( svn_temp_serializer__get_length(context) + - APR_ALIGN_DEFAULT(initial_length)); + + svn_temp_serializer__pop(context); +} + +/* Utility function to serialize the ENTRIES into a new serialization + * context to be returned. + * + * Temporary allocation will be made form SCRATCH_POOL. + */ +static svn_temp_serializer__context_t * +serialize_dir(apr_array_header_t *entries, + apr_pool_t *scratch_pool) +{ + dir_data_t dir_data; + int i = 0; + svn_temp_serializer__context_t *context; + + /* calculate sizes */ + int count = entries->nelts; + apr_size_t over_provision = 2 + count / 4; + apr_size_t entries_len = (count + over_provision) + * sizeof(svn_fs_x__dirent_t*); + apr_size_t lengths_len = (count + over_provision) * sizeof(apr_uint32_t); + + /* copy the hash entries to an auxiliary struct of known layout */ + dir_data.count = count; + dir_data.over_provision = over_provision; + dir_data.operations = 0; + dir_data.entries = apr_palloc(scratch_pool, entries_len); + dir_data.lengths = apr_palloc(scratch_pool, lengths_len); + + for (i = 0; i < count; ++i) + dir_data.entries[i] = APR_ARRAY_IDX(entries, i, svn_fs_x__dirent_t *); + + /* Serialize that aux. structure into a new one. Also, provide a good + * estimate for the size of the buffer that we will need. */ + context = svn_temp_serializer__init(&dir_data, + sizeof(dir_data), + 50 + count * 200 + entries_len, + scratch_pool); + + /* serialize entries references */ + svn_temp_serializer__push(context, + (const void * const *)&dir_data.entries, + entries_len); + + /* serialize the individual entries and their sub-structures */ + for (i = 0; i < count; ++i) + serialize_dir_entry(context, + &dir_data.entries[i], + &dir_data.lengths[i]); + + svn_temp_serializer__pop(context); + + /* serialize entries references */ + svn_temp_serializer__push(context, + (const void * const *)&dir_data.lengths, + lengths_len); + + return context; +} + +/* Utility function to reconstruct a dir entries array from serialized data + * in BUFFER and DIR_DATA. Allocation will be made form POOL. + */ +static apr_array_header_t * +deserialize_dir(void *buffer, dir_data_t *dir_data, apr_pool_t *pool) +{ + apr_array_header_t *result + = apr_array_make(pool, dir_data->count, sizeof(svn_fs_x__dirent_t *)); + apr_size_t i; + apr_size_t count; + svn_fs_x__dirent_t *entry; + svn_fs_x__dirent_t **entries; + + /* resolve the reference to the entries array */ + svn_temp_deserializer__resolve(buffer, (void **)&dir_data->entries); + entries = dir_data->entries; + + /* fixup the references within each entry and add it to the hash */ + for (i = 0, count = dir_data->count; i < count; ++i) + { + svn_temp_deserializer__resolve(entries, (void **)&entries[i]); + entry = dir_data->entries[i]; + + /* pointer fixup */ + svn_temp_deserializer__resolve(entry, (void **)&entry->name); + + /* add the entry to the hash */ + APR_ARRAY_PUSH(result, svn_fs_x__dirent_t *) = entry; + } + + /* return the now complete hash */ + return result; +} + +void +svn_fs_x__noderev_serialize(svn_temp_serializer__context_t *context, + svn_fs_x__noderev_t * const *noderev_p) +{ + const svn_fs_x__noderev_t *noderev = *noderev_p; + if (noderev == NULL) + return; + + /* serialize the representation struct itself */ + svn_temp_serializer__push(context, + (const void * const *)noderev_p, + sizeof(*noderev)); + + /* serialize sub-structures */ + serialize_representation(context, &noderev->prop_rep); + serialize_representation(context, &noderev->data_rep); + + svn_temp_serializer__add_string(context, &noderev->copyfrom_path); + svn_temp_serializer__add_string(context, &noderev->copyroot_path); + svn_temp_serializer__add_string(context, &noderev->created_path); + + /* return to the caller's nesting level */ + svn_temp_serializer__pop(context); +} + + +void +svn_fs_x__noderev_deserialize(void *buffer, + svn_fs_x__noderev_t **noderev_p, + apr_pool_t *pool) +{ + svn_fs_x__noderev_t *noderev; + + /* fixup the reference to the representation itself, + * if this is part of a parent structure. */ + if (buffer != *noderev_p) + svn_temp_deserializer__resolve(buffer, (void **)noderev_p); + + noderev = *noderev_p; + if (noderev == NULL) + return; + + /* fixup of sub-structures */ + svn_temp_deserializer__resolve(noderev, (void **)&noderev->prop_rep); + svn_temp_deserializer__resolve(noderev, (void **)&noderev->data_rep); + + svn_temp_deserializer__resolve(noderev, (void **)&noderev->copyfrom_path); + svn_temp_deserializer__resolve(noderev, (void **)&noderev->copyroot_path); + svn_temp_deserializer__resolve(noderev, (void **)&noderev->created_path); +} + + +/* Utility function to serialize COUNT svn_txdelta_op_t objects + * at OPS in the given serialization CONTEXT. + */ +static void +serialize_txdelta_ops(svn_temp_serializer__context_t *context, + const svn_txdelta_op_t * const * ops, + apr_size_t count) +{ + if (*ops == NULL) + return; + + /* the ops form a contiguous chunk of memory with no further references */ + svn_temp_serializer__add_leaf(context, + (const void * const *)ops, + count * sizeof(svn_txdelta_op_t)); +} + +/* Utility function to serialize W in the given serialization CONTEXT. + */ +static void +serialize_txdeltawindow(svn_temp_serializer__context_t *context, + svn_txdelta_window_t * const * w) +{ + svn_txdelta_window_t *window = *w; + + /* serialize the window struct itself */ + svn_temp_serializer__push(context, + (const void * const *)w, + sizeof(svn_txdelta_window_t)); + + /* serialize its sub-structures */ + serialize_txdelta_ops(context, &window->ops, window->num_ops); + serialize_svn_string(context, &window->new_data); + + svn_temp_serializer__pop(context); +} + +svn_error_t * +svn_fs_x__serialize_txdelta_window(void **buffer, + apr_size_t *buffer_size, + void *item, + apr_pool_t *pool) +{ + svn_fs_x__txdelta_cached_window_t *window_info = item; + svn_stringbuf_t *serialized; + + /* initialize the serialization process and allocate a buffer large + * enough to do without the need of re-allocations in most cases. */ + apr_size_t text_len = window_info->window->new_data + ? window_info->window->new_data->len + : 0; + svn_temp_serializer__context_t *context = + svn_temp_serializer__init(window_info, + sizeof(*window_info), + 500 + text_len, + pool); + + /* serialize the sub-structure(s) */ + serialize_txdeltawindow(context, &window_info->window); + + /* return the serialized result */ + serialized = svn_temp_serializer__get(context); + + *buffer = serialized->data; + *buffer_size = serialized->len; + + return SVN_NO_ERROR; +} + +svn_error_t * +svn_fs_x__deserialize_txdelta_window(void **item, + void *buffer, + apr_size_t buffer_size, + apr_pool_t *pool) +{ + svn_txdelta_window_t *window; + + /* Copy the _full_ buffer as it also contains the sub-structures. */ + svn_fs_x__txdelta_cached_window_t *window_info = + (svn_fs_x__txdelta_cached_window_t *)buffer; + + /* pointer reference fixup */ + svn_temp_deserializer__resolve(window_info, + (void **)&window_info->window); + window = window_info->window; + + svn_temp_deserializer__resolve(window, (void **)&window->ops); + + deserialize_svn_string(window, (svn_string_t**)&window->new_data); + + /* done */ + *item = window_info; + + return SVN_NO_ERROR; +} + +svn_error_t * +svn_fs_x__serialize_manifest(void **data, + apr_size_t *data_len, + void *in, + apr_pool_t *pool) +{ + apr_array_header_t *manifest = in; + + *data_len = sizeof(apr_off_t) *manifest->nelts; + *data = apr_palloc(pool, *data_len); + memcpy(*data, manifest->elts, *data_len); + + return SVN_NO_ERROR; +} + +svn_error_t * +svn_fs_x__deserialize_manifest(void **out, + void *data, + apr_size_t data_len, + apr_pool_t *pool) +{ + apr_array_header_t *manifest = apr_array_make(pool, 1, sizeof(apr_off_t)); + + manifest->nelts = (int) (data_len / sizeof(apr_off_t)); + manifest->nalloc = (int) (data_len / sizeof(apr_off_t)); + manifest->elts = (char*)data; + + *out = manifest; + + return SVN_NO_ERROR; +} + +/* Auxiliary structure representing the content of a properties hash. + This structure is much easier to (de-)serialize than an apr_hash. + */ +typedef struct properties_data_t +{ + /* number of entries in the hash */ + apr_size_t count; + + /* reference to the keys */ + const char **keys; + + /* reference to the values */ + const svn_string_t **values; +} properties_data_t; + +/* Serialize COUNT C-style strings from *STRINGS into CONTEXT. */ +static void +serialize_cstring_array(svn_temp_serializer__context_t *context, + const char ***strings, + apr_size_t count) +{ + apr_size_t i; + const char **entries = *strings; + + /* serialize COUNT entries pointers (the array) */ + svn_temp_serializer__push(context, + (const void * const *)strings, + count * sizeof(const char*)); + + /* serialize array elements */ + for (i = 0; i < count; ++i) + svn_temp_serializer__add_string(context, &entries[i]); + + svn_temp_serializer__pop(context); +} + +/* Serialize COUNT svn_string_t* items from *STRINGS into CONTEXT. */ +static void +serialize_svn_string_array(svn_temp_serializer__context_t *context, + const svn_string_t ***strings, + apr_size_t count) +{ + apr_size_t i; + const svn_string_t **entries = *strings; + + /* serialize COUNT entries pointers (the array) */ + svn_temp_serializer__push(context, + (const void * const *)strings, + count * sizeof(const char*)); + + /* serialize array elements */ + for (i = 0; i < count; ++i) + serialize_svn_string(context, &entries[i]); + + svn_temp_serializer__pop(context); +} + +svn_error_t * +svn_fs_x__serialize_properties(void **data, + apr_size_t *data_len, + void *in, + apr_pool_t *pool) +{ + apr_hash_t *hash = in; + properties_data_t properties; + svn_temp_serializer__context_t *context; + apr_hash_index_t *hi; + svn_stringbuf_t *serialized; + apr_size_t i; + + /* create our auxiliary data structure */ + properties.count = apr_hash_count(hash); + properties.keys = apr_palloc(pool, sizeof(const char*) * (properties.count + 1)); + properties.values = apr_palloc(pool, sizeof(const char*) * properties.count); + + /* populate it with the hash entries */ + for (hi = apr_hash_first(pool, hash), i=0; hi; hi = apr_hash_next(hi), ++i) + { + properties.keys[i] = apr_hash_this_key(hi); + properties.values[i] = apr_hash_this_val(hi); + } + + /* serialize it */ + context = svn_temp_serializer__init(&properties, + sizeof(properties), + properties.count * 100, + pool); + + properties.keys[i] = ""; + serialize_cstring_array(context, &properties.keys, properties.count + 1); + serialize_svn_string_array(context, &properties.values, properties.count); + + /* 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_properties(void **out, + void *data, + apr_size_t data_len, + apr_pool_t *pool) +{ + apr_hash_t *hash = svn_hash__make(pool); + properties_data_t *properties = (properties_data_t *)data; + size_t i; + + /* de-serialize our auxiliary data structure */ + svn_temp_deserializer__resolve(properties, (void**)&properties->keys); + svn_temp_deserializer__resolve(properties, (void**)&properties->values); + + /* de-serialize each entry and put it into the hash */ + for (i = 0; i < properties->count; ++i) + { + apr_size_t len = properties->keys[i+1] - properties->keys[i] - 1; + svn_temp_deserializer__resolve(properties->keys, + (void**)&properties->keys[i]); + + deserialize_svn_string(properties->values, + (svn_string_t **)&properties->values[i]); + + apr_hash_set(hash, + properties->keys[i], len, + properties->values[i]); + } + + /* done */ + *out = hash; + + return SVN_NO_ERROR; +} + +/** Caching svn_fs_x__noderev_t objects. **/ + +svn_error_t * +svn_fs_x__serialize_node_revision(void **buffer, + apr_size_t *buffer_size, + void *item, + apr_pool_t *pool) +{ + svn_stringbuf_t *serialized; + svn_fs_x__noderev_t *noderev = item; + + /* create an (empty) serialization context with plenty of (initial) + * buffer space. */ + svn_temp_serializer__context_t *context = + svn_temp_serializer__init(NULL, 0, + 1024 - SVN_TEMP_SERIALIZER__OVERHEAD, + pool); + + /* serialize the noderev */ + svn_fs_x__noderev_serialize(context, &noderev); + + /* return serialized data */ + serialized = svn_temp_serializer__get(context); + *buffer = serialized->data; + *buffer_size = serialized->len; + + return SVN_NO_ERROR; +} + +svn_error_t * +svn_fs_x__deserialize_node_revision(void **item, + void *buffer, + apr_size_t buffer_size, + apr_pool_t *pool) +{ + /* Copy the _full_ buffer as it also contains the sub-structures. */ + svn_fs_x__noderev_t *noderev = (svn_fs_x__noderev_t *)buffer; + + /* fixup of all pointers etc. */ + svn_fs_x__noderev_deserialize(noderev, &noderev, pool); + + /* done */ + *item = noderev; + return SVN_NO_ERROR; +} + +/* Utility function that returns the directory serialized inside CONTEXT + * to DATA and DATA_LEN. */ +static svn_error_t * +return_serialized_dir_context(svn_temp_serializer__context_t *context, + void **data, + apr_size_t *data_len) +{ + svn_stringbuf_t *serialized = svn_temp_serializer__get(context); + + *data = serialized->data; + *data_len = serialized->blocksize; + ((dir_data_t *)serialized->data)->len = serialized->len; + + return SVN_NO_ERROR; +} + +svn_error_t * +svn_fs_x__serialize_dir_entries(void **data, + apr_size_t *data_len, + void *in, + apr_pool_t *pool) +{ + apr_array_header_t *dir = in; + + /* serialize the dir content into a new serialization context + * and return the serialized data */ + return return_serialized_dir_context(serialize_dir(dir, pool), + data, + data_len); +} + +svn_error_t * +svn_fs_x__deserialize_dir_entries(void **out, + void *data, + apr_size_t data_len, + apr_pool_t *pool) +{ + /* Copy the _full_ buffer as it also contains the sub-structures. */ + dir_data_t *dir_data = (dir_data_t *)data; + + /* reconstruct the hash from the serialized data */ + *out = deserialize_dir(dir_data, dir_data, pool); + + return SVN_NO_ERROR; +} + +svn_error_t * +svn_fs_x__get_sharded_offset(void **out, + const void *data, + apr_size_t data_len, + void *baton, + apr_pool_t *pool) +{ + const apr_off_t *manifest = data; + apr_int64_t shard_pos = *(apr_int64_t *)baton; + + *(apr_off_t *)out = manifest[shard_pos]; + + return SVN_NO_ERROR; +} + +/* Utility function that returns the lowest index of the first entry in + * *ENTRIES that points to a dir entry with a name equal or larger than NAME. + * If an exact match has been found, *FOUND will be set to TRUE. COUNT is + * the number of valid entries in ENTRIES. + */ +static apr_size_t +find_entry(svn_fs_x__dirent_t **entries, + const char *name, + apr_size_t count, + svn_boolean_t *found) +{ + /* binary search for the desired entry by name */ + apr_size_t lower = 0; + apr_size_t upper = count; + apr_size_t middle; + + for (middle = upper / 2; lower < upper; middle = (upper + lower) / 2) + { + const svn_fs_x__dirent_t *entry = + svn_temp_deserializer__ptr(entries, (const void *const *)&entries[middle]); + const char* entry_name = + svn_temp_deserializer__ptr(entry, (const void *const *)&entry->name); + + int diff = strcmp(entry_name, name); + if (diff < 0) + lower = middle + 1; + else + upper = middle; + } + + /* check whether we actually found a match */ + *found = FALSE; + if (lower < count) + { + const svn_fs_x__dirent_t *entry = + svn_temp_deserializer__ptr(entries, (const void *const *)&entries[lower]); + const char* entry_name = + svn_temp_deserializer__ptr(entry, (const void *const *)&entry->name); + + if (strcmp(entry_name, name) == 0) + *found = TRUE; + } + + return lower; +} + +/* Utility function that returns TRUE if entry number IDX in ENTRIES has the + * name NAME. + */ +static svn_boolean_t +found_entry(const svn_fs_x__dirent_t * const *entries, + const char *name, + apr_size_t idx) +{ + /* check whether we actually found a match */ + const svn_fs_x__dirent_t *entry = + svn_temp_deserializer__ptr(entries, (const void *const *)&entries[idx]); + const char* entry_name = + svn_temp_deserializer__ptr(entry, (const void *const *)&entry->name); + + return strcmp(entry_name, name) == 0; +} + +svn_error_t * +svn_fs_x__extract_dir_entry(void **out, + const void *data, + apr_size_t data_len, + void *baton, + apr_pool_t *pool) +{ + const dir_data_t *dir_data = data; + svn_fs_x__ede_baton_t *b = baton; + svn_boolean_t found; + apr_size_t pos; + + /* resolve the reference to the entries array */ + const svn_fs_x__dirent_t * const *entries = + svn_temp_deserializer__ptr(data, (const void *const *)&dir_data->entries); + + /* resolve the reference to the lengths array */ + const apr_uint32_t *lengths = + svn_temp_deserializer__ptr(data, (const void *const *)&dir_data->lengths); + + /* Special case: Early out for empty directories. + That simplifies tests further down the road. */ + *out = NULL; + if (dir_data->count == 0) + return SVN_NO_ERROR; + + /* HINT _might_ be the position we hit last time. + If within valid range, check whether HINT+1 is a hit. */ + if ( b->hint < dir_data->count - 1 + && found_entry(entries, b->name, b->hint + 1)) + { + /* Got lucky. */ + pos = b->hint + 1; + found = TRUE; + } + else + { + /* Binary search for the desired entry by name. */ + pos = find_entry((svn_fs_x__dirent_t **)entries, b->name, + dir_data->count, &found); + } + + /* Remember the hit index - if we FOUND the entry. */ + if (found) + b->hint = pos; + + /* de-serialize that entry or return NULL, if no match has been found */ + if (found) + { + const svn_fs_x__dirent_t *source = + svn_temp_deserializer__ptr(entries, (const void *const *)&entries[pos]); + + /* Entries have been serialized one-by-one, each time including all + * nested structures and strings. Therefore, they occupy a single + * block of memory whose end-offset is either the beginning of the + * next entry or the end of the buffer + */ + apr_size_t size = lengths[pos]; + + /* copy & deserialize the entry */ + svn_fs_x__dirent_t *new_entry = apr_palloc(pool, size); + memcpy(new_entry, source, size); + + svn_temp_deserializer__resolve(new_entry, (void **)&new_entry->name); + *(svn_fs_x__dirent_t **)out = new_entry; + } + + return SVN_NO_ERROR; +} + +/* Utility function for svn_fs_x__replace_dir_entry that implements the + * modification as a simply deserialize / modify / serialize sequence. + */ +static svn_error_t * +slowly_replace_dir_entry(void **data, + apr_size_t *data_len, + void *baton, + apr_pool_t *pool) +{ + replace_baton_t *replace_baton = (replace_baton_t *)baton; + dir_data_t *dir_data = (dir_data_t *)*data; + apr_array_header_t *dir; + int idx = -1; + svn_fs_x__dirent_t *entry; + + SVN_ERR(svn_fs_x__deserialize_dir_entries((void **)&dir, + *data, + dir_data->len, + pool)); + + entry = svn_fs_x__find_dir_entry(dir, replace_baton->name, &idx); + + /* Replacement or removal? */ + if (replace_baton->new_entry) + { + /* Replace ENTRY with / insert the NEW_ENTRY */ + if (entry) + APR_ARRAY_IDX(dir, idx, svn_fs_x__dirent_t *) + = replace_baton->new_entry; + else + svn_sort__array_insert(dir, &replace_baton->new_entry, idx); + } + else + { + /* Remove the old ENTRY. */ + if (entry) + svn_sort__array_delete(dir, idx, 1); + } + + return svn_fs_x__serialize_dir_entries(data, data_len, dir, pool); +} + +svn_error_t * +svn_fs_x__replace_dir_entry(void **data, + apr_size_t *data_len, + void *baton, + apr_pool_t *pool) +{ + replace_baton_t *replace_baton = (replace_baton_t *)baton; + dir_data_t *dir_data = (dir_data_t *)*data; + svn_boolean_t found; + svn_fs_x__dirent_t **entries; + apr_uint32_t *lengths; + apr_uint32_t length; + apr_size_t pos; + + svn_temp_serializer__context_t *context; + + /* after quite a number of operations, let's re-pack everything. + * This is to limit the number of wasted space as we cannot overwrite + * existing data but must always append. */ + if (dir_data->operations > 2 + dir_data->count / 4) + return slowly_replace_dir_entry(data, data_len, baton, pool); + + /* resolve the reference to the entries array */ + entries = (svn_fs_x__dirent_t **) + svn_temp_deserializer__ptr((const char *)dir_data, + (const void *const *)&dir_data->entries); + + /* resolve the reference to the lengths array */ + lengths = (apr_uint32_t *) + svn_temp_deserializer__ptr((const char *)dir_data, + (const void *const *)&dir_data->lengths); + + /* binary search for the desired entry by name */ + pos = find_entry(entries, replace_baton->name, dir_data->count, &found); + + /* handle entry removal (if found at all) */ + if (replace_baton->new_entry == NULL) + { + if (found) + { + /* remove reference to the entry from the index */ + memmove(&entries[pos], + &entries[pos + 1], + sizeof(entries[pos]) * (dir_data->count - pos)); + memmove(&lengths[pos], + &lengths[pos + 1], + sizeof(lengths[pos]) * (dir_data->count - pos)); + + dir_data->count--; + dir_data->over_provision++; + dir_data->operations++; + } + + return SVN_NO_ERROR; + } + + /* if not found, prepare to insert the new entry */ + if (!found) + { + /* fallback to slow operation if there is no place left to insert an + * new entry to index. That will automatically give add some spare + * entries ("overprovision"). */ + if (dir_data->over_provision == 0) + return slowly_replace_dir_entry(data, data_len, baton, pool); + + /* make entries[index] available for pointing to the new entry */ + memmove(&entries[pos + 1], + &entries[pos], + sizeof(entries[pos]) * (dir_data->count - pos)); + memmove(&lengths[pos + 1], + &lengths[pos], + sizeof(lengths[pos]) * (dir_data->count - pos)); + + dir_data->count++; + dir_data->over_provision--; + dir_data->operations++; + } + + /* de-serialize the new entry */ + entries[pos] = replace_baton->new_entry; + context = svn_temp_serializer__init_append(dir_data, + entries, + dir_data->len, + *data_len, + pool); + serialize_dir_entry(context, &entries[pos], &length); + + /* return the updated serialized data */ + SVN_ERR (return_serialized_dir_context(context, + data, + data_len)); + + /* since the previous call may have re-allocated the buffer, the lengths + * pointer may no longer point to the entry in that buffer. Therefore, + * re-map it again and store the length value after that. */ + + dir_data = (dir_data_t *)*data; + lengths = (apr_uint32_t *) + svn_temp_deserializer__ptr((const char *)dir_data, + (const void *const *)&dir_data->lengths); + lengths[pos] = length; + + return SVN_NO_ERROR; +} + +svn_error_t * +svn_fs_x__serialize_rep_header(void **data, + apr_size_t *data_len, + void *in, + apr_pool_t *pool) +{ + svn_fs_x__rep_header_t *copy = apr_palloc(pool, sizeof(*copy)); + *copy = *(svn_fs_x__rep_header_t *)in; + + *data_len = sizeof(svn_fs_x__rep_header_t); + *data = copy; + + return SVN_NO_ERROR; +} + +svn_error_t * +svn_fs_x__deserialize_rep_header(void **out, + void *data, + apr_size_t data_len, + apr_pool_t *pool) +{ + svn_fs_x__rep_header_t *copy = apr_palloc(pool, sizeof(*copy)); + SVN_ERR_ASSERT(data_len == sizeof(*copy)); + + *copy = *(svn_fs_x__rep_header_t *)data; + *out = data; + + return SVN_NO_ERROR; +} + +/* Utility function to serialize change CHANGE_P in the given serialization + * CONTEXT. + */ +static void +serialize_change(svn_temp_serializer__context_t *context, + svn_fs_x__change_t * const *change_p) +{ + const svn_fs_x__change_t * change = *change_p; + if (change == NULL) + return; + + /* serialize the change struct itself */ + svn_temp_serializer__push(context, + (const void * const *)change_p, + sizeof(*change)); + + /* serialize sub-structures */ + svn_temp_serializer__add_string(context, &change->path.data); + svn_temp_serializer__add_string(context, &change->copyfrom_path); + + /* return to the caller's nesting level */ + svn_temp_serializer__pop(context); +} + +/* Utility function to serialize the CHANGE_P within the given + * serialization CONTEXT. + */ +static void +deserialize_change(void *buffer, + svn_fs_x__change_t **change_p, + apr_pool_t *pool) +{ + svn_fs_x__change_t * change; + + /* fix-up of the pointer to the struct in question */ + svn_temp_deserializer__resolve(buffer, (void **)change_p); + + change = *change_p; + if (change == NULL) + return; + + /* fix-up of sub-structures */ + svn_temp_deserializer__resolve(change, (void **)&change->path.data); + svn_temp_deserializer__resolve(change, (void **)&change->copyfrom_path); +} + +/* Auxiliary structure representing the content of a svn_fs_x__change_t array. + This structure is much easier to (de-)serialize than an APR array. + */ +typedef struct changes_data_t +{ + /* number of entries in the array */ + int count; + + /* reference to the changes */ + svn_fs_x__change_t **changes; +} changes_data_t; + +svn_error_t * +svn_fs_x__serialize_changes(void **data, + apr_size_t *data_len, + void *in, + apr_pool_t *pool) +{ + apr_array_header_t *array = in; + changes_data_t changes; + svn_temp_serializer__context_t *context; + svn_stringbuf_t *serialized; + int i; + + /* initialize our auxiliary data structure and link it to the + * array elements */ + changes.count = array->nelts; + changes.changes = (svn_fs_x__change_t **)array->elts; + + /* serialize it and all its elements */ + context = svn_temp_serializer__init(&changes, + sizeof(changes), + changes.count * 250, + pool); + + svn_temp_serializer__push(context, + (const void * const *)&changes.changes, + changes.count * sizeof(svn_fs_x__change_t*)); + + for (i = 0; i < changes.count; ++i) + serialize_change(context, &changes.changes[i]); + + 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_changes(void **out, + void *data, + apr_size_t data_len, + apr_pool_t *pool) +{ + int i; + changes_data_t *changes = (changes_data_t *)data; + apr_array_header_t *array = apr_array_make(pool, 0, + sizeof(svn_fs_x__change_t *)); + + /* de-serialize our auxiliary data structure */ + svn_temp_deserializer__resolve(changes, (void**)&changes->changes); + + /* de-serialize each entry and add it to the array */ + for (i = 0; i < changes->count; ++i) + deserialize_change(changes->changes, + (svn_fs_x__change_t **)&changes->changes[i], + pool); + + /* Use the changes buffer as the array's data buffer + * (DATA remains valid for at least as long as POOL). */ + array->elts = (char *)changes->changes; + array->nelts = changes->count; + array->nalloc = changes->count; + + /* done */ + *out = array; + + return SVN_NO_ERROR; +} + +/* Auxiliary structure representing the content of a svn_mergeinfo_t hash. + This structure is much easier to (de-)serialize than an APR array. + */ +typedef struct mergeinfo_data_t +{ + /* number of paths in the hash */ + unsigned count; + + /* COUNT keys (paths) */ + const char **keys; + + /* COUNT keys lengths (strlen of path) */ + apr_ssize_t *key_lengths; + + /* COUNT entries, each giving the number of ranges for the key */ + int *range_counts; + + /* all ranges in a single, concatenated buffer */ + svn_merge_range_t *ranges; +} mergeinfo_data_t; + +svn_error_t * +svn_fs_x__serialize_mergeinfo(void **data, + apr_size_t *data_len, + void *in, + apr_pool_t *pool) +{ + svn_mergeinfo_t mergeinfo = in; + mergeinfo_data_t merges; + svn_temp_serializer__context_t *context; + svn_stringbuf_t *serialized; + apr_hash_index_t *hi; + unsigned i; + int k; + apr_size_t range_count; + + /* initialize our auxiliary data structure */ + merges.count = apr_hash_count(mergeinfo); + merges.keys = apr_palloc(pool, sizeof(*merges.keys) * merges.count); + merges.key_lengths = apr_palloc(pool, sizeof(*merges.key_lengths) * + merges.count); + merges.range_counts = apr_palloc(pool, sizeof(*merges.range_counts) * + merges.count); + + i = 0; + range_count = 0; + for (hi = apr_hash_first(pool, mergeinfo); hi; hi = apr_hash_next(hi), ++i) + { + svn_rangelist_t *ranges; + apr_hash_this(hi, (const void**)&merges.keys[i], + &merges.key_lengths[i], + (void **)&ranges); + merges.range_counts[i] = ranges->nelts; + range_count += ranges->nelts; + } + + merges.ranges = apr_palloc(pool, sizeof(*merges.ranges) * range_count); + + i = 0; + for (hi = apr_hash_first(pool, mergeinfo); hi; hi = apr_hash_next(hi)) + { + svn_rangelist_t *ranges = apr_hash_this_val(hi); + for (k = 0; k < ranges->nelts; ++k, ++i) + merges.ranges[i] = *APR_ARRAY_IDX(ranges, k, svn_merge_range_t*); + } + + /* serialize it and all its elements */ + context = svn_temp_serializer__init(&merges, + sizeof(merges), + range_count * 30, + pool); + + /* keys array */ + svn_temp_serializer__push(context, + (const void * const *)&merges.keys, + merges.count * sizeof(*merges.keys)); + + for (i = 0; i < merges.count; ++i) + svn_temp_serializer__add_string(context, &merges.keys[i]); + + svn_temp_serializer__pop(context); + + /* key lengths array */ + svn_temp_serializer__add_leaf(context, + (const void * const *)&merges.key_lengths, + merges.count * sizeof(*merges.key_lengths)); + + /* range counts array */ + svn_temp_serializer__add_leaf(context, + (const void * const *)&merges.range_counts, + merges.count * sizeof(*merges.range_counts)); + + /* ranges */ + svn_temp_serializer__add_leaf(context, + (const void * const *)&merges.ranges, + range_count * sizeof(*merges.ranges)); + + /* 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_mergeinfo(void **out, + void *data, + apr_size_t data_len, + apr_pool_t *pool) +{ + unsigned i; + int k, n; + mergeinfo_data_t *merges = (mergeinfo_data_t *)data; + svn_mergeinfo_t mergeinfo; + + /* de-serialize our auxiliary data structure */ + svn_temp_deserializer__resolve(merges, (void**)&merges->keys); + svn_temp_deserializer__resolve(merges, (void**)&merges->key_lengths); + svn_temp_deserializer__resolve(merges, (void**)&merges->range_counts); + svn_temp_deserializer__resolve(merges, (void**)&merges->ranges); + + /* de-serialize keys and add entries to the result */ + n = 0; + mergeinfo = svn_hash__make(pool); + for (i = 0; i < merges->count; ++i) + { + svn_rangelist_t *ranges = apr_array_make(pool, + merges->range_counts[i], + sizeof(svn_merge_range_t*)); + for (k = 0; k < merges->range_counts[i]; ++k, ++n) + APR_ARRAY_PUSH(ranges, svn_merge_range_t*) = &merges->ranges[n]; + + svn_temp_deserializer__resolve(merges->keys, + (void**)&merges->keys[i]); + apr_hash_set(mergeinfo, merges->keys[i], merges->key_lengths[i], ranges); + } + + /* done */ + *out = mergeinfo; + + return SVN_NO_ERROR; +} + |