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 /*----------------------------------------------------*/ 00045 00046 /** Reading/writing hashtables to disk 00047 * 00048 * @defgroup svn_hash_read_write reading and writing hashtables to disk 00049 * @{ 00050 */ 00051 00052 /** 00053 * The conventional terminator for hash dumps. 00054 * 00055 * @since New in 1.1. 00056 */ 00057 #define SVN_HASH_TERMINATOR "END" 00058 00059 /** 00060 * Read a hash table from @a stream, storing the resultants names and 00061 * values in @a hash. Use a @a pool for all allocations. @a hash will 00062 * have <tt>const char *</tt> keys and <tt>svn_string_t *</tt> values. 00063 * If @a terminator is NULL, expect the hash to be terminated by the 00064 * end of the stream; otherwise, expect the hash to be terminated by a 00065 * line containing @a terminator. Pass @c SVN_HASH_TERMINATOR to use 00066 * the conventional terminator "END". 00067 * 00068 * @since New in 1.1. 00069 */ 00070 svn_error_t *svn_hash_read2(apr_hash_t *hash, 00071 svn_stream_t *stream, 00072 const char *terminator, 00073 apr_pool_t *pool); 00074 00075 /** 00076 * Dump @a hash to @a stream. Use @a pool for all allocations. @a 00077 * hash has <tt>const char *</tt> keys and <tt>svn_string_t *</tt> 00078 * values. If @a terminator is not NULL, terminate the hash with a 00079 * line containing @a terminator. 00080 * 00081 * @since New in 1.1. 00082 */ 00083 svn_error_t *svn_hash_write2(apr_hash_t *hash, 00084 svn_stream_t *stream, 00085 const char *terminator, 00086 apr_pool_t *pool); 00087 00088 /** 00089 * Similar to svn_hash_read2(), but allows @a stream to contain 00090 * deletion lines which remove entries from @a hash as well as adding 00091 * to it. 00092 * 00093 * @since New in 1.1. 00094 */ 00095 svn_error_t *svn_hash_read_incremental(apr_hash_t *hash, 00096 svn_stream_t *stream, 00097 const char *terminator, 00098 apr_pool_t *pool); 00099 00100 /** 00101 * Similar to svn_hash_write2(), but only writes out entries for 00102 * keys which differ between @a hash and @a oldhash, and also writes 00103 * out deletion lines for keys which are present in @a oldhash but not 00104 * in @a hash. 00105 * 00106 * @since New in 1.1. 00107 */ 00108 svn_error_t *svn_hash_write_incremental(apr_hash_t *hash, 00109 apr_hash_t *oldhash, 00110 svn_stream_t *stream, 00111 const char *terminator, 00112 apr_pool_t *pool); 00113 00114 /** 00115 * This function behaves like svn_hash_read2(), but it only works 00116 * on an apr_file_t input, empty files are accepted, and the hash is 00117 * expected to be terminated with a line containing "END" or 00118 * "PROPS-END". 00119 * 00120 * @deprecated Provided for backward compatibility with the 1.0 API. 00121 */ 00122 svn_error_t *svn_hash_read(apr_hash_t *hash, 00123 apr_file_t *srcfile, 00124 apr_pool_t *pool); 00125 00126 /** 00127 * This function behaves like svn_hash_write2(), but it only works 00128 * on an apr_file_t output, and the terminator is always "END". 00129 * 00130 * @deprecated Provided for backward compatibility with the 1.0 API. 00131 */ 00132 svn_error_t *svn_hash_write(apr_hash_t *hash, 00133 apr_file_t *destfile, 00134 apr_pool_t *pool); 00135 00136 /** @} */ 00137 00138 00139 /** Taking the "diff" of two hash tables. 00140 * 00141 * @defgroup svn_hash_diff taking the diff of two hash tables. 00142 * @{ 00143 */ 00144 00145 /** Hash key status indicator for svn_hash_diff_func_t. */ 00146 enum svn_hash_diff_key_status 00147 { 00148 /* Key is present in both hashes. */ 00149 svn_hash_diff_key_both, 00150 00151 /* Key is present in first hash only. */ 00152 svn_hash_diff_key_a, 00153 00154 /* Key is present in second hash only. */ 00155 svn_hash_diff_key_b 00156 }; 00157 00158 00159 /** Function type for expressing a key's status between two hash tables. */ 00160 typedef svn_error_t *(*svn_hash_diff_func_t) 00161 (const void *key, apr_ssize_t klen, 00162 enum svn_hash_diff_key_status status, 00163 void *baton); 00164 00165 00166 /** Take the diff of two hashtables. 00167 * 00168 * For each key in the union of @a hash_a's and @a hash_b's keys, invoke 00169 * @a diff_func exactly once, passing the key, the key's length, an enum 00170 * @c svn_hash_diff_key_status indicating which table(s) the key appears 00171 * in, and @a diff_func_baton. 00172 * 00173 * Process all keys of @a hash_a first, then all remaining keys of @a hash_b. 00174 * 00175 * If @a diff_func returns error, return that error immediately, without 00176 * applying @a diff_func to anything else. 00177 * 00178 * @a hash_a or @a hash_b or both may be null; treat a null table as though 00179 * empty. 00180 * 00181 * Use @a pool for temporary allocation. 00182 */ 00183 svn_error_t *svn_hash_diff(apr_hash_t *hash_a, 00184 apr_hash_t *hash_b, 00185 svn_hash_diff_func_t diff_func, 00186 void *diff_func_baton, 00187 apr_pool_t *pool); 00188 00189 /** @} */ 00190 00191 #ifdef __cplusplus 00192 } 00193 #endif /* __cplusplus */ 00194 00195 #endif /* SVN_HASH_H */