1 /* changes.h --- FSX changed paths lists container 2 * 3 * ==================================================================== 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 * ==================================================================== 21 */ 22 23 #ifndef SVN_LIBSVN_FS_X_CHANGES_H 24 #define SVN_LIBSVN_FS_X_CHANGES_H 25 26 #include "svn_io.h" 27 #include "fs.h" 28 29 /* Entries in a revision's change list tend to be widely redundant (similar 30 * changes to similar paths). Even more so, change lists from a larger 31 * revision range also tend to overlap. 32 * 33 * In its serialized form, the svn_fs_x__changes_t container extracts most 34 * of that redundancy and the run-time representation is also much smaller 35 * than sum of the respective svn_fs_x__change_t* arrays. 36 * 37 * As with other containers, this one has two modes: 'construction', in 38 * which you may add data to it, and 'getter' in which there is only r/o 39 * access to the data. 40 */ 41 42 /* An opaque collection of change lists (apr_array_header_t * of 43 * svn_fs_x__change_t *). 44 */ 45 typedef struct svn_fs_x__changes_t svn_fs_x__changes_t; 46 47 /* Create and populate changes containers. */ 48 49 /* Create and return a new changes container with an initial capacity of 50 * INITIAL_COUNT svn_fs_x__change_t objects. 51 * Allocate the result in RESULT_POOL. 52 */ 53 svn_fs_x__changes_t * 54 svn_fs_x__changes_create(apr_size_t initial_count, 55 apr_pool_t *result_pool); 56 57 /* Start a new change list CHANGES (implicitly terminating the previous one) 58 * and return its index in *LIST_INDEX. Append all changes from LIST to 59 * that new change list. 60 */ 61 svn_error_t * 62 svn_fs_x__changes_append_list(apr_size_t *list_index, 63 svn_fs_x__changes_t *changes, 64 apr_array_header_t *list); 65 66 /* Return a rough estimate in bytes for the serialized representation 67 * of CHANGES. 68 */ 69 apr_size_t 70 svn_fs_x__changes_estimate_size(const svn_fs_x__changes_t *changes); 71 72 /* Read changes containers. */ 73 74 /* From CHANGES, access the change list with the given IDX and extract the 75 * next entries according to CONTEXT. Allocate the result in RESULT_POOL 76 * and return it in *LIST. 77 */ 78 svn_error_t * 79 svn_fs_x__changes_get_list(apr_array_header_t **list, 80 const svn_fs_x__changes_t *changes, 81 apr_size_t idx, 82 svn_fs_x__changes_context_t *context, 83 apr_pool_t *result_pool); 84 85 /* I/O interface. */ 86 87 /* Write a serialized representation of CHANGES to STREAM. 88 * Use SCRATCH_POOL for temporary allocations. 89 */ 90 svn_error_t * 91 svn_fs_x__write_changes_container(svn_stream_t *stream, 92 const svn_fs_x__changes_t *changes, 93 apr_pool_t *scratch_pool); 94 95 /* Read a changes container from its serialized representation in STREAM. 96 * Allocate the result in RESULT_POOL and return it in *CHANGES_P. Use 97 * SCRATCH_POOL for temporary allocations. 98 */ 99 svn_error_t * 100 svn_fs_x__read_changes_container(svn_fs_x__changes_t **changes_p, 101 svn_stream_t *stream, 102 apr_pool_t *result_pool, 103 apr_pool_t *scratch_pool); 104 105 /* Implements #svn_cache__serialize_func_t for svn_fs_x__changes_t objects. 106 */ 107 svn_error_t * 108 svn_fs_x__serialize_changes_container(void **data, 109 apr_size_t *data_len, 110 void *in, 111 apr_pool_t *pool); 112 113 /* Implements #svn_cache__deserialize_func_t for svn_fs_x__changes_t objects. 114 */ 115 svn_error_t * 116 svn_fs_x__deserialize_changes_container(void **out, 117 void *data, 118 apr_size_t data_len, 119 apr_pool_t *result_pool); 120 121 /* Baton type to be used with svn_fs_x__changes_get_list_func. */ 122 typedef struct svn_fs_x__changes_get_list_baton_t 123 { 124 /* Sub-item to query */ 125 apr_uint32_t sub_item; 126 127 /* Deliver data starting from this index within the changes list. */ 128 int start; 129 130 /* To be set by svn_fs_x__changes_get_list_func: 131 Did we deliver the last change in that list? */ 132 svn_boolean_t *eol; 133 } svn_fs_x__changes_get_list_baton_t; 134 135 /* Implements svn_cache__partial_getter_func_t for svn_fs_x__changes_t, 136 * setting *OUT to the change list (apr_array_header_t *) selected by 137 * the svn_fs_x__changes_get_list_baton_t passed in as *BATON. This 138 * function is similar to svn_fs_x__changes_get_list but operates on 139 * the cache serialized representation of the container. 140 */ 141 svn_error_t * 142 svn_fs_x__changes_get_list_func(void **out, 143 const void *data, 144 apr_size_t data_len, 145 void *baton, 146 apr_pool_t *pool); 147 148 #endif 149