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_error.h" 00032 00033 00034 #ifdef __cplusplus 00035 extern "C" { 00036 #endif /* __cplusplus */ 00037 00038 00039 /** The longest the "K <number>" line can be in one of our hashdump files. */ 00040 #define SVN_KEYLINE_MAXLEN 100 00041 00042 00043 /*----------------------------------------------------*/ 00044 00045 /** Reading/writing hashtables to disk 00046 * 00047 * @defgroup svn_hash_read_write reading and writing hashtables to disk 00048 * @{ 00049 */ 00050 00051 /** Read a hash table from @a srcfile, storing the resultants names and 00052 * values in @a hash. Use a @a pool for all allocations. @a hash will 00053 * have <tt>const char *</tt> keys and <tt>svn_string_t *</tt> values. 00054 */ 00055 svn_error_t *svn_hash_read (apr_hash_t *hash, 00056 apr_file_t *srcfile, 00057 apr_pool_t *pool); 00058 00059 /** Dump @a hash to @a destfile. Use @a pool for all allocations. @a hash 00060 * has <tt>const char *</tt> keys and <tt>svn_string_t *</tt> values. 00061 */ 00062 svn_error_t *svn_hash_write (apr_hash_t *hash, 00063 apr_file_t *destfile, 00064 apr_pool_t *pool); 00065 00066 /** @} */ 00067 00068 00069 /** Taking the "diff" of two hash tables. 00070 * 00071 * @defgroup svn_hash_diff taking the diff of two hash tables. 00072 * @{ 00073 */ 00074 00075 /** Hash key status indicator for svn_hash_diff_func_t. */ 00076 enum svn_hash_diff_key_status 00077 { 00078 /* Key is present in both hashes. */ 00079 svn_hash_diff_key_both, 00080 00081 /* Key is present in first hash only. */ 00082 svn_hash_diff_key_a, 00083 00084 /* Key is present in second hash only. */ 00085 svn_hash_diff_key_b 00086 }; 00087 00088 00089 /** Function type for expressing a key's status between two hash tables. */ 00090 typedef svn_error_t *(*svn_hash_diff_func_t) 00091 (const void *key, apr_ssize_t klen, 00092 enum svn_hash_diff_key_status status, 00093 void *baton); 00094 00095 00096 /** Take the diff of two hashtables. 00097 * 00098 * For each key in the union of @a hash_a's and @a hash_b's keys, invoke 00099 * @a diff_func exactly once, passing the key, the key's length, an enum 00100 * @c svn_hash_diff_key_status indicating which table(s) the key appears 00101 * in, and @a diff_func_baton. 00102 * 00103 * Process all keys of @a hash_a first, then all remaining keys of @a hash_b. 00104 * 00105 * If @a diff_func returns error, return that error immediately, without 00106 * applying @a diff_func to anything else. 00107 * 00108 * @a hash_a or @a hash_b or both may be null; treat a null table as though 00109 * empty. 00110 * 00111 * Use @a pool for temporary allocation. 00112 */ 00113 svn_error_t *svn_hash_diff (apr_hash_t *hash_a, 00114 apr_hash_t *hash_b, 00115 svn_hash_diff_func_t diff_func, 00116 void *diff_func_baton, 00117 apr_pool_t *pool); 00118 00119 /** @} */ 00120 00121 #ifdef __cplusplus 00122 } 00123 #endif /* __cplusplus */ 00124 00125 #endif /* SVN_HASH_H */