subversion/libsvn_fs_base/reps-strings.h

   1 /* reps-strings.h : interpreting representations with respect to strings
   2  *
   3  * ====================================================================
   4  * Copyright (c) 2000-2004 CollabNet.  All rights reserved.
   5  *
   6  * This software is licensed as described in the file COPYING, which
   7  * you should have received as part of this distribution.  The terms
   8  * are also available at http://subversion.tigris.org/license-1.html.
   9  * If newer versions of this license are posted there, you may use a
  10  * newer version instead, at your option.
  11  *
  12  * This software consists of voluntary contributions made by many
  13  * individuals.  For exact contribution history, see the revision
  14  * history and logs, available at http://subversion.tigris.org/.
  15  * ====================================================================
  16  */
  17
  18 #ifndef SVN_LIBSVN_FS_REPS_STRINGS_H
  19 #define SVN_LIBSVN_FS_REPS_STRINGS_H
  20
  21 #define APU_WANT_DB
  22 #include <apu_want.h>
  23
  24 #include "svn_io.h"
  25 #include "svn_fs.h"
  26
  27 #include "trail.h"
  28
  29
  30 #ifdef __cplusplus
  31 extern "C" {
  32 #endif /* __cplusplus */
  33
  34
  35 \f
  36 /* Get or create a mutable representation in FS, store the new rep's
  37    key in *NEW_REP_KEY.
  38
  39    TXN_ID is the id of the Subversion transaction under which this occurs.
  40
  41    If REP_KEY is already a mutable representation, set *NEW_REP_KEY to
  42    REP_KEY, else set *NEW_REP_KEY to a brand new rep key allocated in
  43    POOL. */
  44 svn_error_t *svn_fs_base__get_mutable_rep(const char **new_rep_key,
  45                                           const char *rep_key,
  46                                           svn_fs_t *fs,
  47                                           const char *txn_id,
  48                                           trail_t *trail,
  49                                           apr_pool_t *pool);
  50
  51
  52 /* Delete REP_KEY from FS if REP_KEY is mutable, as part of trail, or
  53    do nothing if REP_KEY is immutable.  If a mutable rep is deleted,
  54    the string it refers to is deleted as well.  TXN_ID is the id of
  55    the Subversion transaction under which this occurs.
  56
  57    If no such rep, return SVN_ERR_FS_NO_SUCH_REPRESENTATION.  */
  58 svn_error_t *svn_fs_base__delete_rep_if_mutable(svn_fs_t *fs,
  59                                                 const char *rep_key,
  60                                                 const char *txn_id,
  61                                                 trail_t *trail,
  62                                                 apr_pool_t *pool);
  63
  64
  65
  66 \f
  67 /*** Reading and writing rep contents. ***/
  68
  69 /* Set *SIZE_P to the size of REP_KEY's contents in FS, as part of TRAIL.
  70    Note: this is the fulltext size, no matter how the contents are
  71    represented in storage.  */
  72 svn_error_t *svn_fs_base__rep_contents_size(svn_filesize_t *size_p,
  73                                             svn_fs_t *fs,
  74                                             const char *rep_key,
  75                                             trail_t *trail,
  76                                             apr_pool_t *pool);
  77
  78
  79 /* Put into DIGEST the MD5 checksum for REP_KEY in FS, as part of TRAIL.
  80    This is the prerecorded checksum for the rep's contents' fulltext.
  81    If no checksum is available, do not calculate one dynamically, just
  82    put all 0's into DIGEST.  (By convention, the all-zero checksum is
  83    considered to match any checksum.) */
  84 svn_error_t *svn_fs_base__rep_contents_checksum(unsigned char digest[],
  85                                                 svn_fs_t *fs,
  86                                                 const char *rep_key,
  87                                                 trail_t *trail,
  88                                                 apr_pool_t *pool);
  89
  90
  91 /* Set STR->data to the contents of REP_KEY in FS, and STR->len to the
  92    contents' length, as part of TRAIL.  The data is allocated in
  93    POOL.  If an error occurs, the effect on STR->data and
  94    STR->len is undefined.
  95
  96    Note: this is the fulltext contents, no matter how the contents are
  97    represented in storage.  */
  98 svn_error_t *svn_fs_base__rep_contents(svn_string_t *str,
  99                                        svn_fs_t *fs,
 100                                        const char *rep_key,
 101                                        trail_t *trail,
 102                                        apr_pool_t *pool);
 103
 104
 105 /* Set *RS_P to a stream to read the contents of REP_KEY in FS.
 106    Allocate the stream in POOL.
 107
 108    REP_KEY may be null, in which case reads just return 0 bytes.
 109
 110    If USE_TRAIL_FOR_READS is TRUE, the stream's reads are part
 111    of TRAIL; otherwise, each read happens in an internal, one-off
 112    trail (though TRAIL is still required).  POOL may be TRAIL->pool. */
 113 svn_error_t *
 114 svn_fs_base__rep_contents_read_stream(svn_stream_t **rs_p,
 115                                       svn_fs_t *fs,
 116                                       const char *rep_key,
 117                                       svn_boolean_t use_trail_for_reads,
 118                                       trail_t *trail,
 119                                       apr_pool_t *pool);
 120
 121
 122 /* Set *WS_P to a stream to write the contents of REP_KEY.  Allocate
 123    the stream in POOL.  TXN_ID is the id of the Subversion transaction
 124    under which this occurs.
 125
 126    If USE_TRAIL_FOR_WRITES is TRUE, the stream's writes are part
 127    of TRAIL; otherwise, each write happens in an internal, one-off
 128    trail (though TRAIL is still required).  POOL may be TRAIL->pool.
 129
 130    If REP_KEY is not mutable, writes to *WS_P will return the
 131    error SVN_ERR_FS_REP_NOT_MUTABLE.  */
 132 svn_error_t *
 133 svn_fs_base__rep_contents_write_stream(svn_stream_t **ws_p,
 134                                        svn_fs_t *fs,
 135                                        const char *rep_key,
 136                                        const char *txn_id,
 137                                        svn_boolean_t use_trail_for_writes,
 138                                        trail_t *trail,
 139                                        apr_pool_t *pool);
 140
 141
 142 \f
 143 /*** Deltified storage. ***/
 144
 145 /* Offer TARGET the chance to store its contents as a delta against
 146    SOURCE, in FS, as part of TRAIL.  TARGET and SOURCE are both
 147    representation keys.
 148
 149    This usually results in TARGET's data being stored as a diff
 150    against SOURCE; but it might not, if it turns out to be more
 151    efficient to store the contents some other way.  */
 152 svn_error_t *svn_fs_base__rep_deltify(svn_fs_t *fs,
 153                                       const char *target,
 154                                       const char *source,
 155                                       trail_t *trail,
 156                                       apr_pool_t *pool);
 157
 158
 159
 160 #ifdef __cplusplus
 161 }
 162 #endif /* __cplusplus */
 163
 164 #endif /* SVN_LIBSVN_FS_REPS_STRINGS_H */