00001 /** 00002 * @copyright 00003 * ==================================================================== 00004 * Copyright (c) 2000-2004 CollabNet. All rights reserved. 00005 * 00006 * This software is licensed as described in the file COPYING, which 00007 * you should have received as part of this distribution. The terms 00008 * are also available at http://subversion.tigris.org/license-1.html. 00009 * If newer versions of this license are posted there, you may use a 00010 * newer version instead, at your option. 00011 * 00012 * This software consists of voluntary contributions made by many 00013 * individuals. For exact contribution history, see the revision 00014 * history and logs, available at http://subversion.tigris.org/. 00015 * ==================================================================== 00016 * @endcopyright 00017 * 00018 * @file svn_hash.h 00019 * @brief Dumping and reading hash tables to/from files. 00020 */ 00021 00022 00023 #ifndef SVN_HASH_H 00024 #define SVN_HASH_H 00025 00026 #include <apr_pools.h> 00027 #include <apr_hash.h> 00028 #include <apr_file_io.h> 00029 00030 #include "svn_types.h" 00031 #include "svn_io.h" 00032 #include "svn_error.h" 00033 00034 00035 #ifdef __cplusplus 00036 extern "C" { 00037 #endif /* __cplusplus */ 00038 00039 00040 /** The longest the "K <number>" line can be in one of our hashdump files. */ 00041 #define SVN_KEYLINE_MAXLEN 100 00042 00043 /** 00044 * @defgroup svn_hash_support Hash table serialization support 00045 * @{ 00046 */ 00047 00048 /*----------------------------------------------------*/ 00049 00050 /** Reading/writing hashtables to disk 00051 * 00052 * @defgroup svn_hash_read_write Reading and writing hashtables to disk 00053 * @{ 00054 */ 00055 00056 /** 00057 * The conventional terminator for hash dumps. 00058 * 00059 * @since New in 1.1. 00060 */ 00061 #define SVN_HASH_TERMINATOR "END" 00062 00063 /** 00064 * Read a hash table from @a stream, storing the resultants names and 00065 * values in @a hash. Use a @a pool for all allocations. @a hash will 00066 * have <tt>const char *</tt> keys and <tt>svn_string_t *</tt> values. 00067 * If @a terminator is NULL, expect the hash to be terminated by the 00068 * end of the stream; otherwise, expect the hash to be terminated by a 00069 * line containing @a terminator. Pass @c SVN_HASH_TERMINATOR to use 00070 * the conventional terminator "END". 00071 * 00072 * @since New in 1.1. 00073 */ 00074 svn_error_t *svn_hash_read2(apr_hash_t *hash, 00075 svn_stream_t *stream, 00076 const char *terminator, 00077 apr_pool_t *pool); 00078 00079 /** 00080 * Dump @a hash to @a stream. Use @a pool for all allocations. @a 00081 * hash has <tt>const char *</tt> keys and <tt>svn_string_t *</tt> 00082 * values. If @a terminator is not NULL, terminate the hash with a 00083 * line containing @a terminator. 00084 * 00085 * @since New in 1.1. 00086 */ 00087 svn_error_t *svn_hash_write2(apr_hash_t *hash, 00088 svn_stream_t *stream, 00089 const char *terminator, 00090 apr_pool_t *pool); 00091 00092 /** 00093 * Similar to svn_hash_read2(), but allows @a stream to contain 00094 * deletion lines which remove entries from @a hash as well as adding 00095 * to it. 00096 * 00097 * @since New in 1.1. 00098 */ 00099 svn_error_t *svn_hash_read_incremental(apr_hash_t *hash, 00100 svn_stream_t *stream, 00101 const char *terminator, 00102 apr_pool_t *pool); 00103 00104 /** 00105 * Similar to svn_hash_write2(), but only writes out entries for 00106 * keys which differ between @a hash and @a oldhash, and also writes 00107 * out deletion lines for keys which are present in @a oldhash but not 00108 * in @a hash. 00109 * 00110 * @since New in 1.1. 00111 */ 00112 svn_error_t *svn_hash_write_incremental(apr_hash_t *hash, 00113 apr_hash_t *oldhash, 00114 svn_stream_t *stream, 00115 const char *terminator, 00116 apr_pool_t *pool); 00117 00118 /** 00119 * This function behaves like svn_hash_read2(), but it only works 00120 * on an apr_file_t input, empty files are accepted, and the hash is 00121 * expected to be terminated with a line containing "END" or 00122 * "PROPS-END". 00123 * 00124 * @deprecated Provided for backward compatibility with the 1.0 API. 00125 */ 00126 svn_error_t *svn_hash_read(apr_hash_t *hash, 00127 apr_file_t *srcfile, 00128 apr_pool_t *pool); 00129 00130 /** 00131 * This function behaves like svn_hash_write2(), but it only works 00132 * on an apr_file_t output, and the terminator is always "END". 00133 * 00134 * @deprecated Provided for backward compatibility with the 1.0 API. 00135 */ 00136 svn_error_t *svn_hash_write(apr_hash_t *hash, 00137 apr_file_t *destfile, 00138 apr_pool_t *pool); 00139 00140 /** @} */ 00141 00142 00143 /** Taking the "diff" of two hash tables. 00144 * 00145 * @defgroup svn_hash_diff Taking the diff of two hash tables. 00146 * @{ 00147 */ 00148 00149 /** Hash key status indicator for svn_hash_diff_func_t. */ 00150 enum svn_hash_diff_key_status 00151 { 00152 /* Key is present in both hashes. */ 00153 svn_hash_diff_key_both, 00154 00155 /* Key is present in first hash only. */ 00156 svn_hash_diff_key_a, 00157 00158 /* Key is present in second hash only. */ 00159 svn_hash_diff_key_b 00160 }; 00161 00162 00163 /** Function type for expressing a key's status between two hash tables. */ 00164 typedef svn_error_t *(*svn_hash_diff_func_t) 00165 (const void *key, apr_ssize_t klen, 00166 enum svn_hash_diff_key_status status, 00167 void *baton); 00168 00169 00170 /** Take the diff of two hashtables. 00171 * 00172 * For each key in the union of @a hash_a's and @a hash_b's keys, invoke 00173 * @a diff_func exactly once, passing the key, the key's length, an enum 00174 * @c svn_hash_diff_key_status indicating which table(s) the key appears 00175 * in, and @a diff_func_baton. 00176 * 00177 * Process all keys of @a hash_a first, then all remaining keys of @a hash_b. 00178 * 00179 * If @a diff_func returns error, return that error immediately, without 00180 * applying @a diff_func to anything else. 00181 * 00182 * @a hash_a or @a hash_b or both may be NULL; treat a null table as though 00183 * empty. 00184 * 00185 * Use @a pool for temporary allocation. 00186 */ 00187 svn_error_t *svn_hash_diff(apr_hash_t *hash_a, 00188 apr_hash_t *hash_b, 00189 svn_hash_diff_func_t diff_func, 00190 void *diff_func_baton, 00191 apr_pool_t *pool); 00192 00193 /** @} */ 00194 00195 00196 /** 00197 * @defgroup svn_hash_misc Miscellaneous hash APIs 00198 * @{ 00199 */ 00200 00201 /** 00202 * Return the keys to @a hash in @a *array. The keys are assumed to be 00203 * (const char *). The keys are in no particular order. 00204 * 00205 * @a *array itself is allocated in @a pool; however, the keys are not 00206 * copied from the hash. 00207 * 00208 * @since New in 1.5. 00209 */ 00210 svn_error_t *svn_hash_keys(apr_array_header_t **array, 00211 apr_hash_t *hash, 00212 apr_pool_t *pool); 00213 00214 /** 00215 * Set @a *hash to a new hash whose keys come from the items in @a keys 00216 * (an array of <tt>const char *</tt> items), and whose values are 00217 * match their corresponding key. Use @a pool for all allocations 00218 * (including @a *hash, its keys, and its values). 00219 * 00220 * @since New in 1.5. 00221 */ 00222 svn_error_t *svn_hash_from_cstring_keys(apr_hash_t **hash, 00223 const apr_array_header_t *keys, 00224 apr_pool_t *pool); 00225 00226 /** 00227 * Clear any key/value pairs in the hash table. A wrapper for a 00228 * apr_hash_clear(), which isn't available until APR 1.3.0. 00229 * 00230 * @since New in 1.5. 00231 */ 00232 svn_error_t *svn_hash__clear(apr_hash_t *hash); 00233 00234 /** @} */ 00235 00236 /** @} */ 00237 00238 #ifdef __cplusplus 00239 } 00240 #endif /* __cplusplus */ 00241 00242 #endif /* SVN_HASH_H */