1/** 2 * @copyright 3 * ==================================================================== 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 * ==================================================================== 21 * @endcopyright 22 * 23 * @file svn_delta.h 24 * @brief Delta-parsing 25 */ 26 27/* ==================================================================== */ 28 29 30 31#ifndef SVN_DELTA_H 32#define SVN_DELTA_H 33 34#include <apr.h> 35#include <apr_pools.h> 36#include <apr_hash.h> 37#include <apr_tables.h> 38#include <apr_file_io.h> /* for apr_file_t */ 39 40#include "svn_types.h" 41#include "svn_string.h" 42#include "svn_io.h" 43#include "svn_checksum.h" 44 45#ifdef __cplusplus 46extern "C" { 47#endif /* __cplusplus */ 48 49 50 51/** This compression level effectively disables data compression. 52 * However, the data pre-processing costs may still not be zero. 53 * 54 * @since New in 1.7. 55 */ 56#define SVN_DELTA_COMPRESSION_LEVEL_NONE 0 57 58/** This is the maximum compression level we can pass to zlib. 59 * 60 * @since New in 1.7. 61 */ 62#define SVN_DELTA_COMPRESSION_LEVEL_MAX 9 63 64/** This is the default compression level we pass to zlib. It 65 * should be between 0 and 9, with higher numbers resulting in 66 * better compression rates but slower operation. 67 * 68 * @since New in 1.7. 69 */ 70#define SVN_DELTA_COMPRESSION_LEVEL_DEFAULT 5 71 72/** 73 * Get libsvn_delta version information. 74 * 75 * @since New in 1.1. 76 */ 77const svn_version_t * 78svn_delta_version(void); 79 80/** 81 * @defgroup delta_support Delta generation and handling 82 * 83 * @{ 84 */ 85 86/** Text deltas. 87 * 88 * A text delta represents the difference between two strings of 89 * bytes, the `source' string and the `target' string. Given a source 90 * string and a target string, we can compute a text delta; given a 91 * source string and a delta, we can reconstruct the target string. 92 * However, note that deltas are not reversible: you cannot always 93 * reconstruct the source string given the target string and delta. 94 * 95 * Since text deltas can be very large, the interface here allows us 96 * to produce and consume them in pieces. Each piece, represented by 97 * an #svn_txdelta_window_t structure, describes how to produce the 98 * next section of the target string. 99 * 100 * To compute a new text delta: 101 * 102 * - We call svn_txdelta() on the streams we want to compare. That 103 * returns us an #svn_txdelta_stream_t object. 104 * 105 * - We then call svn_txdelta_next_window() on the stream object 106 * repeatedly. Each call returns a new #svn_txdelta_window_t 107 * object, which describes the next portion of the target string. 108 * When svn_txdelta_next_window() returns zero, we are done building 109 * the target string. 110 * 111 * @defgroup svn_delta_txt_delta Text deltas 112 * @{ 113 */ 114 115/** Action codes for text delta instructions. */ 116enum svn_delta_action { 117 /* Note: The svndiff implementation relies on the values assigned in 118 * this enumeration matching the instruction encoding values. */ 119 120 /** Append the @a length bytes at @a offset in the source view to the 121 * target. 122 * 123 * It must be the case that 0 <= @a offset < @a offset + 124 * @a length <= size of source view. 125 */ 126 svn_txdelta_source, 127 128 /** Append the @a length bytes at @a offset in the target view, to the 129 * target. 130 * 131 * It must be the case that 0 <= @a offset < current position in the 132 * target view. 133 * 134 * However! @a offset + @a length may be *beyond* the end of the existing 135 * target data. "Where the heck does the text come from, then?" 136 * If you start at @a offset, and append @a length bytes one at a time, 137 * it'll work out --- you're adding new bytes to the end at the 138 * same rate you're reading them from the middle. Thus, if your 139 * current target text is "abcdefgh", and you get an #svn_txdelta_target 140 * instruction whose @a offset is 6 and whose @a length is 7, 141 * the resulting string is "abcdefghghghghg". This trick is actually 142 * useful in encoding long runs of consecutive characters, long runs 143 * of CR/LF pairs, etc. 144 */ 145 svn_txdelta_target, 146 147 /** Append the @a length bytes at @a offset in the window's @a new string 148 * to the target. 149 * 150 * It must be the case that 0 <= @a offset < @a offset + 151 * @a length <= length of @a new. Windows MUST use new data in ascending 152 * order with no overlap at the moment; svn_txdelta_to_svndiff() 153 * depends on this. 154 */ 155 svn_txdelta_new 156}; 157 158/** A single text delta instruction. */ 159typedef struct svn_txdelta_op_t 160{ 161 /** Action code of delta instruction */ 162 enum svn_delta_action action_code; 163 /** Offset of delta, see #svn_delta_action for more details. */ 164 apr_size_t offset; 165 /** Number of bytes of delta, see #svn_delta_action for more details. */ 166 apr_size_t length; 167} svn_txdelta_op_t; 168 169 170/** An #svn_txdelta_window_t object describes how to reconstruct a 171 * contiguous section of the target string (the "target view") using a 172 * specified contiguous region of the source string (the "source 173 * view"). It contains a series of instructions which assemble the 174 * new target string text by pulling together substrings from: 175 * 176 * - the source view, 177 * 178 * - the previously constructed portion of the target view, 179 * 180 * - a string of new data contained within the window structure 181 * 182 * The source view must always slide forward from one window to the 183 * next; that is, neither the beginning nor the end of the source view 184 * may move to the left as we read from a window stream. This 185 * property allows us to apply deltas to non-seekable source streams 186 * without making a full copy of the source stream. 187 */ 188typedef struct svn_txdelta_window_t 189{ 190 191 /** The offset of the source view for this window. */ 192 svn_filesize_t sview_offset; 193 194 /** The length of the source view for this window. */ 195 apr_size_t sview_len; 196 197 /** The length of the target view for this window, i.e. the number of 198 * bytes which will be reconstructed by the instruction stream. */ 199 apr_size_t tview_len; 200 201 /** The number of instructions in this window. */ 202 int num_ops; 203 204 /** The number of svn_txdelta_source instructions in this window. If 205 * this number is 0, we don't need to read the source in order to 206 * reconstruct the target view. 207 */ 208 int src_ops; 209 210 /** The instructions for this window. */ 211 const svn_txdelta_op_t *ops; 212 213 /** New data, for use by any `svn_txdelta_new' instructions. */ 214 const svn_string_t *new_data; 215 216} svn_txdelta_window_t; 217 218/** 219 * Return a deep copy of @a window, allocated in @a pool. 220 * 221 * @since New in 1.3. 222 */ 223svn_txdelta_window_t * 224svn_txdelta_window_dup(const svn_txdelta_window_t *window, 225 apr_pool_t *pool); 226 227/** 228 * Compose two delta windows, yielding a third, allocated in @a pool. 229 * 230 * @since New in 1.4 231 * 232 */ 233svn_txdelta_window_t * 234svn_txdelta_compose_windows(const svn_txdelta_window_t *window_A, 235 const svn_txdelta_window_t *window_B, 236 apr_pool_t *pool); 237 238/** 239 * Apply the instructions from @a window to a source view @a sbuf to 240 * produce a target view @a tbuf. 241 * 242 * @a sbuf is assumed to have @a window->sview_len bytes of data and 243 * @a tbuf is assumed to have room for @a tlen bytes of output. @a 244 * tlen may be more than @a window->tview_len, so return the actual 245 * number of bytes written. @a sbuf is not touched and may be NULL if 246 * @a window contains no source-copy operations. This is purely a 247 * memory operation; nothing can go wrong as long as we have a valid 248 * window. 249 * 250 * @since New in 1.4 251 * 252 */ 253void 254svn_txdelta_apply_instructions(svn_txdelta_window_t *window, 255 const char *sbuf, char *tbuf, 256 apr_size_t *tlen); 257 258/** A typedef for functions that consume a series of delta windows, for 259 * use in caller-pushes interfaces. Such functions will typically 260 * apply the delta windows to produce some file, or save the windows 261 * somewhere. At the end of the delta window stream, you must call 262 * this function passing zero for the @a window argument. 263 */ 264typedef svn_error_t *(*svn_txdelta_window_handler_t)( 265 svn_txdelta_window_t *window, void *baton); 266 267 268/** This function will generate delta windows that turn @a source into 269 * @a target, and pushing these windows into the @a handler window handler 270 * callback (passing @a handler_baton to each invocation). 271 * 272 * If @a checksum is not NULL, then a checksum (of kind @a checksum_kind) 273 * will be computed for the target stream, and placed into *checksum. 274 * 275 * If @a cancel_func is not NULL, then it should refer to a cancellation 276 * function (along with @a cancel_baton). 277 * 278 * Results (the checksum) will be allocated from @a result_pool, and all 279 * temporary allocations will be performed in @a scratch_pool. 280 * 281 * Note: this function replaces the combination of svn_txdelta() and 282 * svn_txdelta_send_txstream(). 283 * 284 * @since New in 1.6. 285 */ 286svn_error_t * 287svn_txdelta_run(svn_stream_t *source, 288 svn_stream_t *target, 289 svn_txdelta_window_handler_t handler, 290 void *handler_baton, 291 svn_checksum_kind_t checksum_kind, 292 svn_checksum_t **checksum, 293 svn_cancel_func_t cancel_func, 294 void *cancel_baton, 295 apr_pool_t *result_pool, 296 apr_pool_t *scratch_pool); 297 298 299/** A delta stream --- this is the hat from which we pull a series of 300 * svn_txdelta_window_t objects, which, taken in order, describe the 301 * entire target string. This type is defined within libsvn_delta, and 302 * opaque outside that library. 303 */ 304typedef struct svn_txdelta_stream_t svn_txdelta_stream_t; 305 306 307/** A typedef for a function that will set @a *window to the next 308 * window from a #svn_txdelta_stream_t object. If there are no more 309 * delta windows, NULL will be used. The returned window, if any, 310 * will be allocated in @a pool. @a baton is the baton specified 311 * when the stream was created. 312 * 313 * @since New in 1.4. 314 */ 315typedef svn_error_t * 316(*svn_txdelta_next_window_fn_t)(svn_txdelta_window_t **window, 317 void *baton, 318 apr_pool_t *pool); 319 320/** A typedef for a function that will return the md5 checksum of the 321 * fulltext deltified by a #svn_txdelta_stream_t object. Will 322 * return NULL if the final null window hasn't yet been returned by 323 * the stream. The returned value will be allocated in the same pool 324 * as the stream. @a baton is the baton specified when the stream was 325 * created. 326 * 327 * @since New in 1.4. 328 */ 329typedef const unsigned char * 330(*svn_txdelta_md5_digest_fn_t)(void *baton); 331 332/** Create and return a generic text delta stream with @a baton, @a 333 * next_window and @a md5_digest. Allocate the new stream in @a 334 * pool. 335 * 336 * @since New in 1.4. 337 */ 338svn_txdelta_stream_t * 339svn_txdelta_stream_create(void *baton, 340 svn_txdelta_next_window_fn_t next_window, 341 svn_txdelta_md5_digest_fn_t md5_digest, 342 apr_pool_t *pool); 343 344/** Set @a *window to a pointer to the next window from the delta stream 345 * @a stream. When we have completely reconstructed the target string, 346 * set @a *window to zero. 347 * 348 * The window will be allocated in @a pool. 349 */ 350svn_error_t * 351svn_txdelta_next_window(svn_txdelta_window_t **window, 352 svn_txdelta_stream_t *stream, 353 apr_pool_t *pool); 354 355 356/** Return the md5 digest for the complete fulltext deltified by 357 * @a stream, or @c NULL if @a stream has not yet returned its final 358 * @c NULL window. The digest is allocated in the same memory as @a 359 * STREAM. 360 */ 361const unsigned char * 362svn_txdelta_md5_digest(svn_txdelta_stream_t *stream); 363 364/** Set @a *stream to a pointer to a delta stream that will turn the byte 365 * string from @a source into the byte stream from @a target. 366 * 367 * @a source and @a target are both readable generic streams. When we call 368 * svn_txdelta_next_window() on @a *stream, it will read from @a source and 369 * @a target to gather as much data as it needs. If @a calculate_checksum 370 * is set, you may call svn_txdelta_md5_digest() to get an MD5 checksum 371 * for @a target. 372 * 373 * Do any necessary allocation in a sub-pool of @a pool. 374 * 375 * @since New in 1.8. 376 */ 377void 378svn_txdelta2(svn_txdelta_stream_t **stream, 379 svn_stream_t *source, 380 svn_stream_t *target, 381 svn_boolean_t calculate_checksum, 382 apr_pool_t *pool); 383 384/** Similar to svn_txdelta2 but always calculating the target checksum. 385 * 386 * @deprecated Provided for backward compatibility with the 1.7 API. 387 */ 388SVN_DEPRECATED 389void 390svn_txdelta(svn_txdelta_stream_t **stream, 391 svn_stream_t *source, 392 svn_stream_t *target, 393 apr_pool_t *pool); 394 395 396/** 397 * Return a writable stream which, when fed target data, will send 398 * delta windows to @a handler/@a handler_baton which transform the 399 * data in @a source to the target data. As usual, the window handler 400 * will receive a NULL window to signify the end of the window stream. 401 * The stream handler functions will read data from @a source as 402 * necessary. 403 * 404 * @since New in 1.1. 405 */ 406svn_stream_t * 407svn_txdelta_target_push(svn_txdelta_window_handler_t handler, 408 void *handler_baton, 409 svn_stream_t *source, 410 apr_pool_t *pool); 411 412 413/** Send the contents of @a string to window-handler @a handler/@a baton. 414 * This is effectively a 'copy' operation, resulting in delta windows that 415 * make the target equivalent to the value of @a string. 416 * 417 * All temporary allocation is performed in @a pool. 418 */ 419svn_error_t * 420svn_txdelta_send_string(const svn_string_t *string, 421 svn_txdelta_window_handler_t handler, 422 void *handler_baton, 423 apr_pool_t *pool); 424 425/** Send the contents of @a stream to window-handler @a handler/@a baton. 426 * This is effectively a 'copy' operation, resulting in delta windows that 427 * make the target equivalent to the stream. 428 * 429 * If @a digest is non-NULL, populate it with the md5 checksum for the 430 * fulltext that was deltified (@a digest must be at least 431 * @c APR_MD5_DIGESTSIZE bytes long). 432 * 433 * All temporary allocation is performed in @a pool. 434 */ 435svn_error_t * 436svn_txdelta_send_stream(svn_stream_t *stream, 437 svn_txdelta_window_handler_t handler, 438 void *handler_baton, 439 unsigned char *digest, 440 apr_pool_t *pool); 441 442/** Send the contents of @a txstream to window-handler @a handler/@a baton. 443 * Windows will be extracted from the stream and delivered to the handler. 444 * 445 * All temporary allocation is performed in @a pool. 446 */ 447svn_error_t * 448svn_txdelta_send_txstream(svn_txdelta_stream_t *txstream, 449 svn_txdelta_window_handler_t handler, 450 void *handler_baton, 451 apr_pool_t *pool); 452 453 454/** Send the @a contents of length @a len as a txdelta against an empty 455 * source directly to window-handler @a handler/@a handler_baton. 456 * 457 * All temporary allocation is performed in @a pool. 458 * 459 * @since New in 1.8. 460 */ 461svn_error_t * 462svn_txdelta_send_contents(const unsigned char *contents, 463 apr_size_t len, 464 svn_txdelta_window_handler_t handler, 465 void *handler_baton, 466 apr_pool_t *pool); 467 468/** Prepare to apply a text delta. @a source is a readable generic stream 469 * yielding the source data, @a target is a writable generic stream to 470 * write target data to, and allocation takes place in a sub-pool of 471 * @a pool. On return, @a *handler is set to a window handler function and 472 * @a *handler_baton is set to the value to pass as the @a baton argument to 473 * @a *handler. 474 * 475 * If @a result_digest is non-NULL, it points to APR_MD5_DIGESTSIZE bytes 476 * of storage, and the final call to @a handler populates it with the 477 * MD5 digest of the resulting fulltext. 478 * 479 * If @a error_info is non-NULL, it is inserted parenthetically into 480 * the error string for any error returned by svn_txdelta_apply() or 481 * @a *handler. (It is normally used to provide path information, 482 * since there's nothing else in the delta application's context to 483 * supply a path for error messages.) 484 * 485 * @note To avoid lifetime issues, @a error_info is copied into 486 * @a pool or a subpool thereof. 487 */ 488void 489svn_txdelta_apply(svn_stream_t *source, 490 svn_stream_t *target, 491 unsigned char *result_digest, 492 const char *error_info, 493 apr_pool_t *pool, 494 svn_txdelta_window_handler_t *handler, 495 void **handler_baton); 496 497 498 499 500/*** Producing and consuming svndiff-format text deltas. ***/ 501 502/** Prepare to produce an svndiff-format diff from text delta windows. 503 * @a output is a writable generic stream to write the svndiff data to. 504 * Allocation takes place in a sub-pool of @a pool. On return, @a *handler 505 * is set to a window handler function and @a *handler_baton is set to 506 * the value to pass as the @a baton argument to @a *handler. The svndiff 507 * version is @a svndiff_version. @a compression_level is the zlib 508 * compression level from 0 (no compression) and 9 (maximum compression). 509 * 510 * @since New in 1.7. 511 */ 512void 513svn_txdelta_to_svndiff3(svn_txdelta_window_handler_t *handler, 514 void **handler_baton, 515 svn_stream_t *output, 516 int svndiff_version, 517 int compression_level, 518 apr_pool_t *pool); 519 520/** Similar to svn_txdelta_to_svndiff3(), but always using the SVN default 521 * compression level (#SVN_DELTA_COMPRESSION_LEVEL_DEFAULT). 522 * 523 * @since New in 1.4. 524 * @deprecated Provided for backward compatibility with the 1.6 API. 525 */ 526SVN_DEPRECATED 527void 528svn_txdelta_to_svndiff2(svn_txdelta_window_handler_t *handler, 529 void **handler_baton, 530 svn_stream_t *output, 531 int svndiff_version, 532 apr_pool_t *pool); 533 534/** Similar to svn_txdelta_to_svndiff2, but always using svndiff 535 * version 0. 536 * 537 * @deprecated Provided for backward compatibility with the 1.3 API. 538 */ 539SVN_DEPRECATED 540void 541svn_txdelta_to_svndiff(svn_stream_t *output, 542 apr_pool_t *pool, 543 svn_txdelta_window_handler_t *handler, 544 void **handler_baton); 545 546/** Return a writable generic stream which will parse svndiff-format 547 * data into a text delta, invoking @a handler with @a handler_baton 548 * whenever a new window is ready. If @a error_on_early_close is @c 549 * TRUE, attempting to close this stream before it has handled the entire 550 * svndiff data set will result in #SVN_ERR_SVNDIFF_UNEXPECTED_END, 551 * else this error condition will be ignored. 552 */ 553svn_stream_t * 554svn_txdelta_parse_svndiff(svn_txdelta_window_handler_t handler, 555 void *handler_baton, 556 svn_boolean_t error_on_early_close, 557 apr_pool_t *pool); 558 559/** 560 * Read and parse one delta window in svndiff format from the 561 * readable stream @a stream and place it in @a *window, allocating 562 * the result in @a pool. The caller must take responsibility for 563 * stripping off the four-byte 'SVN@<ver@>' header at the beginning of 564 * the svndiff document before reading the first window, and must 565 * provide the version number (the value of the fourth byte) to each 566 * invocation of this routine with the @a svndiff_version argument. 567 * 568 * @since New in 1.1. 569 */ 570svn_error_t * 571svn_txdelta_read_svndiff_window(svn_txdelta_window_t **window, 572 svn_stream_t *stream, 573 int svndiff_version, 574 apr_pool_t *pool); 575 576/** 577 * Read and skip one delta window in svndiff format from the 578 * file @a file. @a pool is used for temporary allocations. The 579 * caller must take responsibility for stripping off the four-byte 580 * 'SVN@<ver@>' header at the beginning of the svndiff document before 581 * reading or skipping the first window, and must provide the version 582 * number (the value of the fourth byte) to each invocation of this 583 * routine with the @a svndiff_version argument. 584 * 585 * @since New in 1.1. 586 */ 587svn_error_t * 588svn_txdelta_skip_svndiff_window(apr_file_t *file, 589 int svndiff_version, 590 apr_pool_t *pool); 591 592/** @} */ 593 594 595/** Traversing tree deltas. 596 * 597 * In Subversion, we've got various producers and consumers of tree 598 * deltas. 599 * 600 * In processing a `commit' command: 601 * - The client examines its working copy data, and produces a tree 602 * delta describing the changes to be committed. 603 * - The client networking library consumes that delta, and sends them 604 * across the wire as an equivalent series of network requests (for 605 * example, to svnserve as an ra_svn protocol stream, or to an 606 * Apache httpd server as WebDAV commands) 607 * - The server receives those requests and produces a tree delta --- 608 * hopefully equivalent to the one the client produced above. 609 * - The Subversion server module consumes that delta and commits an 610 * appropriate transaction to the filesystem. 611 * 612 * In processing an `update' command, the process is reversed: 613 * - The Subversion server module talks to the filesystem and produces 614 * a tree delta describing the changes necessary to bring the 615 * client's working copy up to date. 616 * - The server consumes this delta, and assembles a reply 617 * representing the appropriate changes. 618 * - The client networking library receives that reply, and produces a 619 * tree delta --- hopefully equivalent to the one the Subversion 620 * server produced above. 621 * - The working copy library consumes that delta, and makes the 622 * appropriate changes to the working copy. 623 * 624 * The simplest approach would be to represent tree deltas using the 625 * obvious data structure. To do an update, the server would 626 * construct a delta structure, and the working copy library would 627 * apply that structure to the working copy; the network layer's job 628 * would simply be to get the structure across the net intact. 629 * 630 * However, we expect that these deltas will occasionally be too large 631 * to fit in a typical workstation's swap area. For example, in 632 * checking out a 200Mb source tree, the entire source tree is 633 * represented by a single tree delta. So it's important to handle 634 * deltas that are too large to fit in swap all at once. 635 * 636 * So instead of representing the tree delta explicitly, we define a 637 * standard way for a consumer to process each piece of a tree delta 638 * as soon as the producer creates it. The #svn_delta_editor_t 639 * structure is a set of callback functions to be defined by a delta 640 * consumer, and invoked by a delta producer. Each invocation of a 641 * callback function describes a piece of the delta --- a file's 642 * contents changing, something being renamed, etc. 643 * 644 * @defgroup svn_delta_tree_deltas Tree deltas 645 * @{ 646 */ 647 648/** A structure full of callback functions the delta source will invoke 649 * as it produces the delta. 650 * 651 * @note Don't try to allocate one of these yourself. Instead, always 652 * use svn_delta_default_editor() or some other constructor, to ensure 653 * that unused slots are filled in with no-op functions. 654 * 655 * <h3>Function Usage</h3> 656 * 657 * Here's how to use these functions to express a tree delta. 658 * 659 * The delta consumer implements the callback functions described in 660 * this structure, and the delta producer invokes them. So the 661 * caller (producer) is pushing tree delta data at the callee 662 * (consumer). 663 * 664 * At the start of traversal, the consumer provides @a edit_baton, a 665 * baton global to the entire delta edit. If there is a target 666 * revision that needs to be set for this operation, the producer 667 * should call the @c set_target_revision function at this point. 668 * 669 * Next, if there are any tree deltas to express, the producer should 670 * pass the @a edit_baton to the @c open_root function, to get a baton 671 * representing root of the tree being edited. 672 * 673 * Most of the callbacks work in the obvious way: 674 * 675 * @c delete_entry 676 * @c add_file 677 * @c add_directory 678 * @c open_file 679 * @c open_directory 680 * 681 * Each of these takes a directory baton, indicating the directory 682 * in which the change takes place, and a @a path argument, giving the 683 * path of the file, subdirectory, or directory entry to change. 684 * 685 * The @a path argument to each of the callbacks is relative to the 686 * root of the edit. Editors will usually want to join this relative 687 * path with some base stored in the edit baton (e.g. a URL, or a 688 * location in the OS filesystem). 689 * 690 * Since every call requires a parent directory baton, including 691 * @c add_directory and @c open_directory, where do we ever get our 692 * initial directory baton, to get things started? The @c open_root 693 * function returns a baton for the top directory of the change. In 694 * general, the producer needs to invoke the editor's @c open_root 695 * function before it can get anything of interest done. 696 * 697 * While @c open_root provides a directory baton for the root of 698 * the tree being changed, the @c add_directory and @c open_directory 699 * callbacks provide batons for other directories. Like the 700 * callbacks above, they take a @a parent_baton and a relative path 701 * @a path, and then return a new baton for the subdirectory being 702 * created / modified --- @a child_baton. The producer can then use 703 * @a child_baton to make further changes in that subdirectory. 704 * 705 * So, if we already have subdirectories named `foo' and `foo/bar', 706 * then the producer can create a new file named `foo/bar/baz.c' by 707 * calling: 708 * 709 * - @c open_root () --- yielding a baton @a root for the top directory 710 * 711 * - @c open_directory (@a root, "foo") --- yielding a baton @a f for `foo' 712 * 713 * - @c open_directory (@a f, "foo/bar") --- yielding a baton @a b for 714 * `foo/bar' 715 * 716 * - @c add_file (@a b, "foo/bar/baz.c") 717 * 718 * When the producer is finished making changes to a directory, it 719 * should call @c close_directory. This lets the consumer do any 720 * necessary cleanup, and free the baton's storage. 721 * 722 * The @c add_file and @c open_file callbacks each return a baton 723 * for the file being created or changed. This baton can then be 724 * passed to @c apply_textdelta to change the file's contents, or 725 * @c change_file_prop to change the file's properties. When the 726 * producer is finished making changes to a file, it should call 727 * @c close_file, to let the consumer clean up and free the baton. 728 * 729 * The @c add_file and @c add_directory functions each take arguments 730 * @a copyfrom_path and @a copyfrom_revision. If @a copyfrom_path is 731 * non-@c NULL, then @a copyfrom_path and @a copyfrom_revision indicate where 732 * the file or directory should be copied from (to create the file 733 * or directory being added). In that case, @a copyfrom_path must be 734 * either a path relative to the root of the edit, or a URI from the 735 * repository being edited. If @a copyfrom_path is @c NULL, then @a 736 * copyfrom_revision must be #SVN_INVALID_REVNUM; it is invalid to 737 * pass a mix of valid and invalid copyfrom arguments. 738 * 739 * 740 * <h3>Function Call Ordering</h3> 741 * 742 * There are six restrictions on the order in which the producer 743 * may use the batons: 744 * 745 * 1. The producer may call @c open_directory, @c add_directory, 746 * @c open_file, @c add_file at most once on any given directory 747 * entry. @c delete_entry may be called at most once on any given 748 * directory entry and may later be followed by @c add_directory or 749 * @c add_file on the same directory entry. @c delete_entry may 750 * not be called on any directory entry after @c open_directory, 751 * @c add_directory, @c open_file or @c add_file has been called on 752 * that directory entry. 753 * 754 * 2. The producer may not close a directory baton until it has 755 * closed all batons for its subdirectories. 756 * 757 * 3. When a producer calls @c open_directory or @c add_directory, 758 * it must specify the most recently opened of the currently open 759 * directory batons. Put another way, the producer cannot have 760 * two sibling directory batons open at the same time. 761 * 762 * 4. A producer must call @c change_dir_prop on a directory either 763 * before opening any of the directory's subdirs or after closing 764 * them, but not in the middle. 765 * 766 * 5. When the producer calls @c open_file or @c add_file, either: 767 * 768 * (a) The producer must follow with any changes to the file 769 * (@c change_file_prop and/or @c apply_textdelta, as applicable), 770 * followed by a @c close_file call, before issuing any other file 771 * or directory calls, or 772 * 773 * (b) The producer must follow with a @c change_file_prop call if 774 * it is applicable, before issuing any other file or directory 775 * calls; later, after all directory batons including the root 776 * have been closed, the producer must issue @c apply_textdelta 777 * and @c close_file calls. 778 * 779 * 6. When the producer calls @c apply_textdelta, it must make all of 780 * the window handler calls (including the @c NULL window at the 781 * end) before issuing any other #svn_delta_editor_t calls. 782 * 783 * So, the producer needs to use directory and file batons as if it 784 * is doing a single depth-first traversal of the tree, with the 785 * exception that the producer may keep file batons open in order to 786 * make @c apply_textdelta calls at the end. 787 * 788 * 789 * <h3>Pool Usage</h3> 790 * 791 * Many editor functions are invoked multiple times, in a sequence 792 * determined by the editor "driver". The driver is responsible for 793 * creating a pool for use on each iteration of the editor function, 794 * and clearing that pool between each iteration. The driver passes 795 * the appropriate pool on each function invocation. 796 * 797 * Based on the requirement of calling the editor functions in a 798 * depth-first style, it is usually customary for the driver to similarly 799 * nest the pools. However, this is only a safety feature to ensure 800 * that pools associated with deeper items are always cleared when the 801 * top-level items are also cleared. The interface does not assume, nor 802 * require, any particular organization of the pools passed to these 803 * functions. In fact, if "postfix deltas" are used for files, the file 804 * pools definitely need to live outside the scope of their parent 805 * directories' pools. 806 * 807 * Note that close_directory can be called *before* a file in that 808 * directory has been closed. That is, the directory's baton is 809 * closed before the file's baton. The implication is that 810 * @c apply_textdelta and @c close_file should not refer to a parent 811 * directory baton UNLESS the editor has taken precautions to 812 * allocate it in a pool of the appropriate lifetime (the @a dir_pool 813 * passed to @c open_directory and @c add_directory definitely does not 814 * have the proper lifetime). In general, it is recommended to simply 815 * avoid keeping a parent directory baton in a file baton. 816 * 817 * 818 * <h3>Errors</h3> 819 * 820 * At least one implementation of the editor interface is 821 * asynchronous; an error from one operation may be detected some 822 * number of operations later. As a result, an editor driver must not 823 * assume that an error from an editing function resulted from the 824 * particular operation being detected. Moreover, once an editing 825 * function (including @c close_edit) returns an error, the edit is 826 * dead; the only further operation which may be called on the editor 827 * is @c abort_edit. 828 */ 829typedef struct svn_delta_editor_t 830{ 831 /** Set the target revision for this edit to @a target_revision. This 832 * call, if used, should precede all other editor calls. 833 * 834 * @note This is typically used only for server->client update-type 835 * operations. It doesn't really make much sense for commit-type 836 * operations, because the revision of a commit isn't known until 837 * the commit is finalized. 838 * 839 * Any temporary allocations may be performed in @a scratch_pool. 840 */ 841 svn_error_t *(*set_target_revision)(void *edit_baton, 842 svn_revnum_t target_revision, 843 apr_pool_t *scratch_pool); 844 845 /** Set @a *root_baton to a baton for the top directory of the change. 846 * (This is the top of the subtree being changed, not necessarily 847 * the root of the filesystem.) As with any other directory baton, the 848 * producer should call @c close_directory on @a root_baton when done. 849 * And as with other @c open_* calls, the @a base_revision here is the 850 * current revision of the directory (before getting bumped up to the 851 * new target revision set with @c set_target_revision). 852 * 853 * Allocations for the returned @a root_baton should be performed in 854 * @a result_pool. It is also typical to (possibly) save this pool for 855 * later usage by @c close_directory. 856 */ 857 svn_error_t *(*open_root)(void *edit_baton, 858 svn_revnum_t base_revision, 859 apr_pool_t *result_pool, 860 void **root_baton); 861 862 863 /** Remove the directory entry at @a path, a child of the directory 864 * represented by @a parent_baton. If @a revision is a valid 865 * revision number, it is used as a sanity check to ensure that you 866 * are really removing the revision of @a path that you think you are. 867 * 868 * Any temporary allocations may be performed in @a scratch_pool. 869 * 870 * @note The @a revision parameter is typically used only for 871 * client->server commit-type operations, allowing the server to 872 * verify that it is deleting what the client thinks it should be 873 * deleting. It only really makes sense in the opposite direction 874 * (during server->client update-type operations) when the trees 875 * whose delta is being described are ancestrally related (that is, 876 * one tree is an ancestor of the other). 877 */ 878 svn_error_t *(*delete_entry)(const char *path, 879 svn_revnum_t revision, 880 void *parent_baton, 881 apr_pool_t *scratch_pool); 882 883 884 /** We are going to add a new subdirectory at @a path, a child of 885 * the directory represented by @a parent_baton. We will use 886 * the value this callback stores in @a *child_baton as the 887 * parent baton for further changes in the new subdirectory. 888 * 889 * If @a copyfrom_path is non-@c NULL, this add has history (i.e., is a 890 * copy), and the origin of the copy may be recorded as 891 * @a copyfrom_path under @a copyfrom_revision. 892 * 893 * Allocations for the returned @a child_baton should be performed in 894 * @a result_pool. It is also typical to (possibly) save this pool for 895 * later usage by @c close_directory. 896 */ 897 svn_error_t *(*add_directory)(const char *path, 898 void *parent_baton, 899 const char *copyfrom_path, 900 svn_revnum_t copyfrom_revision, 901 apr_pool_t *result_pool, 902 void **child_baton); 903 904 /** We are going to make changes in the subdirectory at @a path, a 905 * child of the directory represented by @a parent_baton. 906 * The callback must store a value in @a *child_baton that 907 * should be used as the parent baton for subsequent changes in this 908 * subdirectory. If a valid revnum, @a base_revision is the current 909 * revision of the subdirectory. 910 * 911 * Allocations for the returned @a child_baton should be performed in 912 * @a result_pool. It is also typical to (possibly) save this pool for 913 * later usage by @c close_directory. 914 */ 915 svn_error_t *(*open_directory)(const char *path, 916 void *parent_baton, 917 svn_revnum_t base_revision, 918 apr_pool_t *result_pool, 919 void **child_baton); 920 921 /** Change the value of a directory's property. 922 * - @a dir_baton specifies the directory whose property should change. 923 * - @a name is the name of the property to change. 924 * - @a value is the new (final) value of the property, or @c NULL if the 925 * property should be removed altogether. 926 * 927 * The callback is guaranteed to be called exactly once for each property 928 * whose value differs between the start and the end of the edit. 929 * 930 * Any temporary allocations may be performed in @a scratch_pool. 931 */ 932 svn_error_t *(*change_dir_prop)(void *dir_baton, 933 const char *name, 934 const svn_string_t *value, 935 apr_pool_t *scratch_pool); 936 937 /** We are done processing a subdirectory, whose baton is @a dir_baton 938 * (set by @c add_directory or @c open_directory). We won't be using 939 * the baton any more, so whatever resources it refers to may now be 940 * freed. 941 * 942 * Any temporary allocations may be performed in @a scratch_pool. 943 */ 944 svn_error_t *(*close_directory)(void *dir_baton, 945 apr_pool_t *scratch_pool); 946 947 948 /** In the directory represented by @a parent_baton, indicate that 949 * @a path is present as a subdirectory in the edit source, but 950 * cannot be conveyed to the edit consumer. Currently, this would 951 * only occur because of authorization restrictions, but may change 952 * in the future. 953 * 954 * Any temporary allocations may be performed in @a scratch_pool. 955 */ 956 svn_error_t *(*absent_directory)(const char *path, 957 void *parent_baton, 958 apr_pool_t *scratch_pool); 959 960 /** We are going to add a new file at @a path, a child of the 961 * directory represented by @a parent_baton. The callback can 962 * store a baton for this new file in @a **file_baton; whatever value 963 * it stores there should be passed through to @c apply_textdelta. 964 * 965 * If @a copyfrom_path is non-@c NULL, this add has history (i.e., is a 966 * copy), and the origin of the copy may be recorded as 967 * @a copyfrom_path under @a copyfrom_revision. 968 * 969 * Allocations for the returned @a file_baton should be performed in 970 * @a result_pool. It is also typical to save this pool for later usage 971 * by @c apply_textdelta and possibly @c close_file. 972 * 973 * @note Because the editor driver could be employing the "postfix 974 * deltas" paradigm, @a result_pool could potentially be relatively 975 * long-lived. Every file baton created by the editor for a given 976 * editor drive might be resident in memory similtaneously. Editor 977 * implementations should ideally keep their file batons as 978 * conservative (memory-usage-wise) as possible, and use @a result_pool 979 * only for those batons. (Consider using a subpool of @a result_pool 980 * for scratch work, destroying the subpool before exiting this 981 * function's implementation.) 982 */ 983 svn_error_t *(*add_file)(const char *path, 984 void *parent_baton, 985 const char *copyfrom_path, 986 svn_revnum_t copyfrom_revision, 987 apr_pool_t *result_pool, 988 void **file_baton); 989 990 /** We are going to make changes to a file at @a path, a child of the 991 * directory represented by @a parent_baton. 992 * 993 * The callback can store a baton for this new file in @a **file_baton; 994 * whatever value it stores there should be passed through to 995 * @c apply_textdelta. If a valid revnum, @a base_revision is the 996 * current revision of the file. 997 * 998 * Allocations for the returned @a file_baton should be performed in 999 * @a result_pool. It is also typical to save this pool for later usage 1000 * by @c apply_textdelta and possibly @c close_file. 1001 * 1002 * @note See note about memory usage on @a add_file, which also 1003 * applies here. 1004 */ 1005 svn_error_t *(*open_file)(const char *path, 1006 void *parent_baton, 1007 svn_revnum_t base_revision, 1008 apr_pool_t *result_pool, 1009 void **file_baton); 1010 1011 /** Apply a text delta, yielding the new revision of a file. 1012 * 1013 * @a file_baton indicates the file we're creating or updating, and the 1014 * ancestor file on which it is based; it is the baton set by some 1015 * prior @c add_file or @c open_file callback. 1016 * 1017 * The callback should set @a *handler to a text delta window 1018 * handler; we will then call @a *handler on successive text 1019 * delta windows as we receive them. The callback should set 1020 * @a *handler_baton to the value we should pass as the @a baton 1021 * argument to @a *handler. These values should be allocated within 1022 * @a result_pool. 1023 * 1024 * @a base_checksum is the hex MD5 digest for the base text against 1025 * which the delta is being applied; it is ignored if NULL, and may 1026 * be ignored even if not NULL. If it is not ignored, it must match 1027 * the checksum of the base text against which svndiff data is being 1028 * applied; if it does not, @c apply_textdelta or the @a *handler call 1029 * which detects the mismatch will return the error 1030 * SVN_ERR_CHECKSUM_MISMATCH (if there is no base text, there may 1031 * still be an error if @a base_checksum is neither NULL nor the hex 1032 * MD5 checksum of the empty string). 1033 */ 1034 svn_error_t *(*apply_textdelta)(void *file_baton, 1035 const char *base_checksum, 1036 apr_pool_t *result_pool, 1037 svn_txdelta_window_handler_t *handler, 1038 void **handler_baton); 1039 1040 /** Change the value of a file's property. 1041 * - @a file_baton specifies the file whose property should change. 1042 * - @a name is the name of the property to change. 1043 * - @a value is the new (final) value of the property, or @c NULL if the 1044 * property should be removed altogether. 1045 * 1046 * The callback is guaranteed to be called exactly once for each property 1047 * whose value differs between the start and the end of the edit. 1048 * 1049 * Any temporary allocations may be performed in @a scratch_pool. 1050 */ 1051 svn_error_t *(*change_file_prop)(void *file_baton, 1052 const char *name, 1053 const svn_string_t *value, 1054 apr_pool_t *scratch_pool); 1055 1056 /** We are done processing a file, whose baton is @a file_baton (set by 1057 * @c add_file or @c open_file). We won't be using the baton any 1058 * more, so whatever resources it refers to may now be freed. 1059 * 1060 * @a text_checksum is the hex MD5 digest for the fulltext that 1061 * resulted from a delta application, see @c apply_textdelta. The 1062 * checksum is ignored if NULL. If not null, it is compared to the 1063 * checksum of the new fulltext, and the error 1064 * SVN_ERR_CHECKSUM_MISMATCH is returned if they do not match. If 1065 * there is no new fulltext, @a text_checksum is ignored. 1066 * 1067 * Any temporary allocations may be performed in @a scratch_pool. 1068 */ 1069 svn_error_t *(*close_file)(void *file_baton, 1070 const char *text_checksum, 1071 apr_pool_t *scratch_pool); 1072 1073 /** In the directory represented by @a parent_baton, indicate that 1074 * @a path is present as a file in the edit source, but cannot be 1075 * cannot be conveyed to the edit consumer. Currently, this would 1076 * only occur because of authorization restrictions, but may change 1077 * in the future. 1078 * 1079 * Any temporary allocations may be performed in @a scratch_pool. 1080 */ 1081 svn_error_t *(*absent_file)(const char *path, 1082 void *parent_baton, 1083 apr_pool_t *scratch_pool); 1084 1085 /** All delta processing is done. Call this, with the @a edit_baton for 1086 * the entire edit. 1087 * 1088 * Any temporary allocations may be performed in @a scratch_pool. 1089 */ 1090 svn_error_t *(*close_edit)(void *edit_baton, 1091 apr_pool_t *scratch_pool); 1092 1093 /** The editor-driver has decided to bail out. Allow the editor to 1094 * gracefully clean up things if it needs to. 1095 * 1096 * Any temporary allocations may be performed in @a scratch_pool. 1097 */ 1098 svn_error_t *(*abort_edit)(void *edit_baton, 1099 apr_pool_t *scratch_pool); 1100 1101 /* Be sure to update svn_delta_get_cancellation_editor() and 1102 * svn_delta_default_editor() if you add a new callback here. */ 1103} svn_delta_editor_t; 1104 1105 1106/** Return a default delta editor template, allocated in @a pool. 1107 * 1108 * The editor functions in the template do only the most basic 1109 * baton-swapping: each editor function that produces a baton does so 1110 * by copying its incoming baton into the outgoing baton reference. 1111 * 1112 * This editor is not intended to be useful by itself, but is meant to 1113 * be the basis for a useful editor. After getting a default editor, 1114 * you substitute in your own implementations for the editor functions 1115 * you care about. The ones you don't care about, you don't have to 1116 * implement -- you can rely on the template's implementation to 1117 * safely do nothing of consequence. 1118 */ 1119svn_delta_editor_t * 1120svn_delta_default_editor(apr_pool_t *pool); 1121 1122/** A text-delta window handler which does nothing. 1123 * 1124 * Editors can return this handler from @c apply_textdelta if they don't 1125 * care about text delta windows. 1126 */ 1127svn_error_t * 1128svn_delta_noop_window_handler(svn_txdelta_window_t *window, 1129 void *baton); 1130 1131/** Set @a *editor and @a *edit_baton to a cancellation editor that 1132 * wraps @a wrapped_editor and @a wrapped_baton. 1133 * 1134 * The @a editor will call @a cancel_func with @a cancel_baton when each of 1135 * its functions is called, continuing on to call the corresponding wrapped 1136 * function if @a cancel_func returns #SVN_NO_ERROR. 1137 * 1138 * If @a cancel_func is @c NULL, set @a *editor to @a wrapped_editor and 1139 * @a *edit_baton to @a wrapped_baton. 1140 */ 1141svn_error_t * 1142svn_delta_get_cancellation_editor(svn_cancel_func_t cancel_func, 1143 void *cancel_baton, 1144 const svn_delta_editor_t *wrapped_editor, 1145 void *wrapped_baton, 1146 const svn_delta_editor_t **editor, 1147 void **edit_baton, 1148 apr_pool_t *pool); 1149 1150/** Set @a *editor and @a *edit_baton to an depth-based filtering 1151 * editor that wraps @a wrapped_editor and @a wrapped_baton. 1152 * 1153 * The @a editor will track the depth of this drive against the @a 1154 * requested_depth, taking into account whether not the edit drive is 1155 * making use of a target (via @a has_target), and forward editor 1156 * calls which operate "within" the request depth range through to @a 1157 * wrapped_editor. 1158 * 1159 * @a requested_depth must be one of the following depth values: 1160 * #svn_depth_infinity, #svn_depth_empty, #svn_depth_files, 1161 * #svn_depth_immediates, or #svn_depth_unknown. 1162 * 1163 * If filtering is deemed unnecessary (or if @a requested_depth is 1164 * #svn_depth_unknown), @a *editor and @a *edit_baton will be set to @a 1165 * wrapped_editor and @a wrapped_baton, respectively; otherwise, 1166 * they'll be set to new objects allocated from @a pool. 1167 * 1168 * @note Because the svn_delta_editor_t interface's @c delete_entry() 1169 * function doesn't carry node kind information, a depth-based 1170 * filtering editor being asked to filter for #svn_depth_files but 1171 * receiving a @c delete_entry() call on an immediate child of the 1172 * editor's target is unable to know if that deletion should be 1173 * allowed or filtered out -- a delete of a top-level file is okay in 1174 * this case, a delete of a top-level subdirectory is not. As such, 1175 * this filtering editor takes a conservative approach, and ignores 1176 * top-level deletion requests when filtering for #svn_depth_files. 1177 * Fortunately, most non-depth-aware (pre-1.5) Subversion editor 1178 * drivers can be told to drive non-recursively (where non-recursive 1179 * means essentially #svn_depth_files), which means they won't 1180 * transmit out-of-scope editor commands anyway. 1181 * 1182 * @since New in 1.5. 1183 */ 1184svn_error_t * 1185svn_delta_depth_filter_editor(const svn_delta_editor_t **editor, 1186 void **edit_baton, 1187 const svn_delta_editor_t *wrapped_editor, 1188 void *wrapped_edit_baton, 1189 svn_depth_t requested_depth, 1190 svn_boolean_t has_target, 1191 apr_pool_t *pool); 1192 1193/** @} */ 1194 1195 1196/** Path-based editor drives. 1197 * 1198 * @defgroup svn_delta_path_delta_drivers Path-based delta drivers 1199 * @{ 1200 */ 1201 1202/** Callback function type for svn_delta_path_driver(). 1203 * 1204 * The handler of this callback is given the callback baton @a 1205 * callback_baton, @a path which is a relpath relative to the 1206 * root of the edit, and the @a parent_baton which represents 1207 * path's parent directory as created by the editor passed to 1208 * svn_delta_path_driver(). 1209 * 1210 * If @a path represents a directory, the handler must return a @a 1211 * *dir_baton for @a path, generated from the same editor (so that the 1212 * driver can later close that directory). 1213 * 1214 * If, however, @a path represents a file, the handler should NOT 1215 * return any file batons. It can close any opened or added files 1216 * immediately, or delay that close until the end of the edit when 1217 * svn_delta_path_driver() returns. 1218 * 1219 * Finally, if @a parent_baton is @c NULL, then the root of the edit 1220 * is also one of the paths passed to svn_delta_path_driver(). The 1221 * handler of this callback must call the editor's open_root() 1222 * function and return the top-level root dir baton in @a *dir_baton. 1223 */ 1224typedef svn_error_t *(*svn_delta_path_driver_cb_func_t)( 1225 void **dir_baton, 1226 void *parent_baton, 1227 void *callback_baton, 1228 const char *path, 1229 apr_pool_t *pool); 1230 1231 1232/** Drive @a editor (with its @a edit_baton) to visit each path in @a paths. 1233 * As each path is hit as part of the editor drive, use 1234 * @a callback_func and @a callback_baton to allow the caller to handle 1235 * the portion of the editor drive related to that path. 1236 * 1237 * Each path in @a paths is a (const char *) relpath, relative 1238 * to the root path of the @a edit. The editor drive will be 1239 * performed in the same order as @a paths. The paths should be sorted 1240 * using something like svn_sort_compare_paths to ensure that a depth-first 1241 * pattern is observed for directory/file baton creation. If @a sort_paths 1242 * is set, the function will sort the paths for you. Some callers may need 1243 * further customization of the order (ie. libsvn_delta/compat.c). 1244 * 1245 * Use @a scratch_pool for all necessary allocations. 1246 * 1247 * @since New in 1.8. 1248 */ 1249svn_error_t * 1250svn_delta_path_driver2(const svn_delta_editor_t *editor, 1251 void *edit_baton, 1252 const apr_array_header_t *paths, 1253 svn_boolean_t sort_paths, 1254 svn_delta_path_driver_cb_func_t callback_func, 1255 void *callback_baton, 1256 apr_pool_t *scratch_pool); 1257 1258 1259/** Similar to svn_delta_path_driver2, but takes an (unused) revision, 1260 * and will sort the provided @a paths using svn_sort_compare_paths. 1261 * 1262 * @note In versions prior to 1.8, this function would modify the order 1263 * of elements in @a paths, despite the 'const' marker on the parameter. 1264 * This has been fixed in 1.8. 1265 * 1266 * @deprecated Provided for backward compatibility with the 1.7 API. 1267 */ 1268SVN_DEPRECATED 1269svn_error_t * 1270svn_delta_path_driver(const svn_delta_editor_t *editor, 1271 void *edit_baton, 1272 svn_revnum_t revision, 1273 const apr_array_header_t *paths, 1274 svn_delta_path_driver_cb_func_t callback_func, 1275 void *callback_baton, 1276 apr_pool_t *scratch_pool); 1277 1278/** @} */ 1279 1280 1281/*** File revision iterator types ***/ 1282 1283/** 1284 * The callback invoked by file rev loopers, such as 1285 * svn_ra_plugin_t.get_file_revs2() and svn_repos_get_file_revs2(). 1286 * 1287 * @a baton is provided by the caller, @a path is the pathname of the file 1288 * in revision @a rev and @a rev_props are the revision properties. 1289 * 1290 * If @a delta_handler and @a delta_baton are non-NULL, they may be set to a 1291 * handler/baton which will be called with the delta between the previous 1292 * revision and this one after the return of this callback. They may be 1293 * left as NULL/NULL. 1294 * 1295 * @a result_of_merge will be @c TRUE if the revision being returned was 1296 * included as the result of a merge. 1297 * 1298 * @a prop_diffs is an array of svn_prop_t elements indicating the property 1299 * delta for this and the previous revision. 1300 * 1301 * @a pool may be used for temporary allocations, but you can't rely 1302 * on objects allocated to live outside of this particular call and 1303 * the immediately following calls to @a *delta_handler if any. (Pass 1304 * in a pool via @a baton if need be.) 1305 * 1306 * @since New in 1.5. 1307 */ 1308typedef svn_error_t *(*svn_file_rev_handler_t)( 1309 void *baton, 1310 const char *path, 1311 svn_revnum_t rev, 1312 apr_hash_t *rev_props, 1313 svn_boolean_t result_of_merge, 1314 svn_txdelta_window_handler_t *delta_handler, 1315 void **delta_baton, 1316 apr_array_header_t *prop_diffs, 1317 apr_pool_t *pool); 1318 1319/** 1320 * The old file rev handler interface. 1321 * 1322 * @note #svn_file_rev_handler_old_t is a placeholder type for both 1323 * #svn_repos_file_rev_handler_t and #svn_ra_file_rev_handler_t. It is 1324 * reproduced here for dependency reasons. 1325 * 1326 * @deprecated This type is provided for the svn_compat_wrap_file_rev_handler() 1327 * compatibility wrapper, and should not be used for new development. 1328 * @since New in 1.5. 1329 */ 1330typedef svn_error_t *(*svn_file_rev_handler_old_t)( 1331 void *baton, 1332 const char *path, 1333 svn_revnum_t rev, 1334 apr_hash_t *rev_props, 1335 svn_txdelta_window_handler_t *delta_handler, 1336 void **delta_baton, 1337 apr_array_header_t *prop_diffs, 1338 apr_pool_t *pool); 1339 1340/** Return, in @a *handler2 and @a *handler2_baton a function/baton that 1341 * will call @a handler/@a handler_baton, allocating the @a *handler2_baton 1342 * in @a pool. 1343 * 1344 * @note This is used by compatibility wrappers, which exist in more than 1345 * Subversion core library. 1346 * 1347 * @note #svn_file_rev_handler_old_t is a placeholder type for both 1348 * #svn_repos_file_rev_handler_t and #svn_ra_file_rev_handler_t. It is 1349 * reproduced here for dependency reasons. 1350 * 1351 * @since New in 1.5. 1352 */ 1353void 1354svn_compat_wrap_file_rev_handler(svn_file_rev_handler_t *handler2, 1355 void **handler2_baton, 1356 svn_file_rev_handler_old_t handler, 1357 void *handler_baton, 1358 apr_pool_t *pool); 1359 1360/** @} end group: delta_support */ 1361 1362 1363#ifdef __cplusplus 1364} 1365#endif /* __cplusplus */ 1366 1367#endif /* SVN_DELTA_H */ 1368