src/TortoiseMerge/svninclude/svn_hash.h

   1 /**
   2  * @copyright
   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  * @endcopyright
  22  *
  23  * @file svn_hash.h
  24  * @brief Dumping and reading hash tables to/from files.
  25  */
  26
  27
  28 #ifndef SVN_HASH_H
  29 #define SVN_HASH_H
  30
  31 #include <apr.h>
  32 #include <apr_pools.h>
  33 #include <apr_hash.h>
  34 #include <apr_tables.h>
  35 #include <apr_file_io.h>  /* for apr_file_t */
  36
  37 #include "svn_types.h"
  38 #include "svn_io.h"       /* for svn_stream_t */
  39
  40
  41 #ifdef __cplusplus
  42 extern "C" {
  43 #endif /* __cplusplus */
  44
  45 \f
  46 /** The longest the "K <number>" line can be in one of our hashdump files. */
  47 #define SVN_KEYLINE_MAXLEN 100
  48
  49 /**
  50  * @defgroup svn_hash_support Hash table serialization support
  51  * @{
  52  */
  53
  54 /*----------------------------------------------------*/
  55 \f
  56 /** Reading/writing hashtables to disk
  57  *
  58  * @defgroup svn_hash_read_write Reading and writing hashtables to disk
  59  * @{
  60  */
  61
  62 /**
  63  * The conventional terminator for hash dumps.
  64  *
  65  * @since New in 1.1.
  66  */
  67 #define SVN_HASH_TERMINATOR "END"
  68
  69 /**
  70  * Read a hash table from @a stream, storing the resultants names and
  71  * values in @a hash.  Use a @a pool for all allocations.  @a hash will
  72  * have <tt>const char *</tt> keys and <tt>svn_string_t *</tt> values.
  73  * If @a terminator is NULL, expect the hash to be terminated by the
  74  * end of the stream; otherwise, expect the hash to be terminated by a
  75  * line containing @a terminator.  Pass @c SVN_HASH_TERMINATOR to use
  76  * the conventional terminator "END".
  77  *
  78  * @since New in 1.1.
  79  */
  80 svn_error_t *
  81 svn_hash_read2(apr_hash_t *hash,
  82                svn_stream_t *stream,
  83                const char *terminator,
  84                apr_pool_t *pool);
  85
  86 /**
  87  * Dump @a hash to @a stream.  Use @a pool for all allocations.  @a
  88  * hash has <tt>const char *</tt> keys and <tt>svn_string_t *</tt>
  89  * values.  If @a terminator is not NULL, terminate the hash with a
  90  * line containing @a terminator.
  91  *
  92  * @since New in 1.1.
  93  */
  94 svn_error_t *
  95 svn_hash_write2(apr_hash_t *hash,
  96                 svn_stream_t *stream,
  97                 const char *terminator,
  98                 apr_pool_t *pool);
  99
 100 /**
 101  * Similar to svn_hash_read2(), but allows @a stream to contain
 102  * deletion lines which remove entries from @a hash as well as adding
 103  * to it.
 104  *
 105  * @since New in 1.1.
 106  */
 107 svn_error_t *
 108 svn_hash_read_incremental(apr_hash_t *hash,
 109                           svn_stream_t *stream,
 110                           const char *terminator,
 111                           apr_pool_t *pool);
 112
 113 /**
 114  * Similar to svn_hash_write2(), but only writes out entries for
 115  * keys which differ between @a hash and @a oldhash, and also writes
 116  * out deletion lines for keys which are present in @a oldhash but not
 117  * in @a hash.
 118  *
 119  * @since New in 1.1.
 120  */
 121 svn_error_t *
 122 svn_hash_write_incremental(apr_hash_t *hash,
 123                            apr_hash_t *oldhash,
 124                            svn_stream_t *stream,
 125                            const char *terminator,
 126                            apr_pool_t *pool);
 127
 128 /**
 129  * This function behaves like svn_hash_read2(), but it only works
 130  * on an apr_file_t input, empty files are accepted, and the hash is
 131  * expected to be terminated with a line containing "END" or
 132  * "PROPS-END".
 133  *
 134  * @deprecated Provided for backward compatibility with the 1.0 API.
 135  */
 136 SVN_DEPRECATED
 137 svn_error_t *
 138 svn_hash_read(apr_hash_t *hash,
 139               apr_file_t *srcfile,
 140               apr_pool_t *pool);
 141
 142 /**
 143  * This function behaves like svn_hash_write2(), but it only works
 144  * on an apr_file_t output, and the terminator is always "END".
 145  *
 146  * @deprecated Provided for backward compatibility with the 1.0 API.
 147  */
 148 SVN_DEPRECATED
 149 svn_error_t *
 150 svn_hash_write(apr_hash_t *hash,
 151                apr_file_t *destfile,
 152                apr_pool_t *pool);
 153
 154 /** @} */
 155
 156 \f
 157 /** Taking the "diff" of two hash tables.
 158  *
 159  * @defgroup svn_hash_diff Taking the diff of two hash tables.
 160  * @{
 161  */
 162
 163 /** Hash key status indicator for svn_hash_diff_func_t.  */
 164 enum svn_hash_diff_key_status
 165   {
 166     /* Key is present in both hashes. */
 167     svn_hash_diff_key_both,
 168
 169     /* Key is present in first hash only. */
 170     svn_hash_diff_key_a,
 171
 172     /* Key is present in second hash only. */
 173     svn_hash_diff_key_b
 174   };
 175
 176
 177 /** Function type for expressing a key's status between two hash tables. */
 178 typedef svn_error_t *(*svn_hash_diff_func_t)
 179   (const void *key, apr_ssize_t klen,
 180    enum svn_hash_diff_key_status status,
 181    void *baton);
 182
 183
 184 /** Take the diff of two hashtables.
 185  *
 186  * For each key in the union of @a hash_a's and @a hash_b's keys, invoke
 187  * @a diff_func exactly once, passing the key, the key's length, an enum
 188  * @c svn_hash_diff_key_status indicating which table(s) the key appears
 189  * in, and @a diff_func_baton.
 190  *
 191  * Process all keys of @a hash_a first, then all remaining keys of @a hash_b.
 192  *
 193  * If @a diff_func returns error, return that error immediately, without
 194  * applying @a diff_func to anything else.
 195  *
 196  * @a hash_a or @a hash_b or both may be NULL; treat a null table as though
 197  * empty.
 198  *
 199  * Use @a pool for temporary allocation.
 200  */
 201 svn_error_t *
 202 svn_hash_diff(apr_hash_t *hash_a,
 203               apr_hash_t *hash_b,
 204               svn_hash_diff_func_t diff_func,
 205               void *diff_func_baton,
 206               apr_pool_t *pool);
 207
 208 /** @} */
 209
 210 \f
 211 /**
 212  * @defgroup svn_hash_misc Miscellaneous hash APIs
 213  * @{
 214  */
 215
 216 /**
 217  * Return the keys to @a hash in @a *array.  The keys are assumed to be
 218  * (const char *).  The keys are in no particular order.
 219  *
 220  * @a *array itself is allocated in @a pool; however, the keys are not
 221  * copied from the hash.
 222  *
 223  * @since New in 1.5.
 224  */
 225 svn_error_t *
 226 svn_hash_keys(apr_array_header_t **array,
 227               apr_hash_t *hash,
 228               apr_pool_t *pool);
 229
 230 /**
 231  * Set @a *hash to a new hash whose keys come from the items in @a keys
 232  * (an array of <tt>const char *</tt> items), and whose values are
 233  * match their corresponding key.  Use @a pool for all allocations
 234  * (including @a *hash, its keys, and its values).
 235  *
 236  * @since New in 1.5.
 237  */
 238 svn_error_t *
 239 svn_hash_from_cstring_keys(apr_hash_t **hash,
 240                            const apr_array_header_t *keys,
 241                            apr_pool_t *pool);
 242
 243 /* Shortcut for apr_hash_get() with a const char * key.
 244  *
 245  * @since New in 1.8.
 246  */
 247 #define svn_hash_gets(ht, key) \
 248             apr_hash_get(ht, key, APR_HASH_KEY_STRING)
 249
 250 /* Shortcut for apr_hash_set() with a const char * key.
 251  *
 252  * @since New in 1.8.
 253  */
 254 #define svn_hash_sets(ht, key, val) \
 255             apr_hash_set(ht, key, APR_HASH_KEY_STRING, val)
 256
 257 /** @} */
 258
 259 /** @} */
 260
 261 #ifdef __cplusplus
 262 }
 263 #endif /* __cplusplus */
 264
 265 #endif /* SVN_HASH_H */