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