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1 /*
2 * Copyright (C) 2005 Junio C Hamano
3 */
4 #ifndef DIFF_H
5 #define DIFF_H
7 #include "tree-walk.h"
8 #include "pathspec.h"
9 #include "object.h"
10 #include "oidset.h"
12 /**
13 * The diff API is for programs that compare two sets of files (e.g. two trees,
14 * one tree and the index) and present the found difference in various ways.
15 * The calling program is responsible for feeding the API pairs of files, one
16 * from the "old" set and the corresponding one from "new" set, that are
17 * different.
18 * The library called through this API is called diffcore, and is responsible
19 * for two things.
21 * - finding total rewrites (`-B`), renames (`-M`) and copies (`-C`), and
22 * changes that touch a string (`-S`), as specified by the caller.
24 * - outputting the differences in various formats, as specified by the caller.
26 * Calling sequence
27 * ----------------
29 * - Prepare `struct diff_options` to record the set of diff options, and then
30 * call `repo_diff_setup()` to initialize this structure. This sets up the
31 * vanilla default.
33 * - Fill in the options structure to specify desired output format, rename
34 * detection, etc. `diff_opt_parse()` can be used to parse options given
35 * from the command line in a way consistent with existing git-diff family
36 * of programs.
38 * - Call `diff_setup_done()`; this inspects the options set up so far for
39 * internal consistency and make necessary tweaking to it (e.g. if textual
40 * patch output was asked, recursive behaviour is turned on); the callback
41 * set_default in diff_options can be used to tweak this more.
43 * - As you find different pairs of files, call `diff_change()` to feed
44 * modified files, `diff_addremove()` to feed created or deleted files, or
45 * `diff_unmerge()` to feed a file whose state is 'unmerged' to the API.
46 * These are thin wrappers to a lower-level `diff_queue()` function that is
47 * flexible enough to record any of these kinds of changes.
49 * - Once you finish feeding the pairs of files, call `diffcore_std()`.
50 * This will tell the diffcore library to go ahead and do its work.
52 * - Calling `diff_flush()` will produce the output.
55 struct combine_diff_path;
56 struct commit;
57 struct diff_filespec;
58 struct diff_options;
59 struct diff_queue_struct;
60 struct oid_array;
61 struct option;
62 struct repository;
63 struct rev_info;
64 struct strbuf;
65 struct userdiff_driver;
67 typedef int (*pathchange_fn_t)(struct diff_options *options,
68 struct combine_diff_path *path);
70 typedef void (*change_fn_t)(struct diff_options *options,
71 unsigned old_mode, unsigned new_mode,
72 const struct object_id *old_oid,
73 const struct object_id *new_oid,
74 int old_oid_valid, int new_oid_valid,
75 const char *fullpath,
76 unsigned old_dirty_submodule, unsigned new_dirty_submodule);
78 typedef void (*add_remove_fn_t)(struct diff_options *options,
79 int addremove, unsigned mode,
80 const struct object_id *oid,
81 int oid_valid,
82 const char *fullpath, unsigned dirty_submodule);
84 typedef void (*diff_format_fn_t)(struct diff_queue_struct *q,
85 struct diff_options *options, void *data);
87 typedef struct strbuf *(*diff_prefix_fn_t)(struct diff_options *opt, void *data);
89 #define DIFF_FORMAT_RAW 0x0001
90 #define DIFF_FORMAT_DIFFSTAT 0x0002
91 #define DIFF_FORMAT_NUMSTAT 0x0004
92 #define DIFF_FORMAT_SUMMARY 0x0008
93 #define DIFF_FORMAT_PATCH 0x0010
94 #define DIFF_FORMAT_SHORTSTAT 0x0020
95 #define DIFF_FORMAT_DIRSTAT 0x0040
97 /* These override all above */
98 #define DIFF_FORMAT_NAME 0x0100
99 #define DIFF_FORMAT_NAME_STATUS 0x0200
100 #define DIFF_FORMAT_CHECKDIFF 0x0400
102 /* Same as output_format = 0 but we know that -s flag was given
103 * and we should not give default value to output_format.
105 #define DIFF_FORMAT_NO_OUTPUT 0x0800
107 #define DIFF_FORMAT_CALLBACK 0x1000
109 #define DIFF_FLAGS_INIT { 0 }
110 struct diff_flags {
113 * Tells if tree traversal done by tree-diff should recursively descend
114 * into a tree object pair that are different in preimage and postimage set.
116 unsigned recursive;
117 unsigned tree_in_recursive;
119 /* Affects the way how a file that is seemingly binary is treated. */
120 unsigned binary;
121 unsigned text;
124 * Tells the patch output format not to use abbreviated object names on the
125 * "index" lines.
127 unsigned full_index;
129 /* Affects if diff-files shows removed files. */
130 unsigned silent_on_remove;
133 * Tells the diffcore library that the caller is feeding unchanged
134 * filepairs to allow copies from unmodified files be detected.
136 unsigned find_copies_harder;
138 unsigned follow_renames;
139 unsigned rename_empty;
141 /* Internal; used for optimization to see if there is any change. */
142 unsigned has_changes;
144 unsigned quick;
147 * Tells diff-files that the input is not tracked files but files in random
148 * locations on the filesystem.
150 unsigned no_index;
153 * Tells output routine that it is Ok to call user specified patch output
154 * routine. Plumbing disables this to ensure stable output.
156 unsigned allow_external;
159 * For communication between the calling program and the options parser;
160 * tell the calling program to signal the presence of difference using
161 * program exit code.
163 unsigned exit_with_status;
166 * Tells the library that the calling program is feeding the filepairs
167 * reversed; `one` is two, and `two` is one.
169 unsigned reverse_diff;
171 unsigned check_failed;
172 unsigned relative_name;
173 unsigned ignore_submodules;
174 unsigned dirstat_cumulative;
175 unsigned dirstat_by_file;
176 unsigned allow_textconv;
177 unsigned textconv_set_via_cmdline;
178 unsigned diff_from_contents;
179 unsigned dirty_submodules;
180 unsigned ignore_untracked_in_submodules;
181 unsigned ignore_dirty_submodules;
182 unsigned override_submodule_config;
183 unsigned dirstat_by_line;
184 unsigned funccontext;
185 unsigned default_follow_renames;
186 unsigned stat_with_summary;
187 unsigned suppress_diff_headers;
188 unsigned dual_color_diffed_diffs;
189 unsigned suppress_hunk_header_line_count;
192 static inline void diff_flags_or(struct diff_flags *a,
193 const struct diff_flags *b)
195 char *tmp_a = (char *)a;
196 const char *tmp_b = (const char *)b;
197 int i;
199 for (i = 0; i < sizeof(struct diff_flags); i++)
200 tmp_a[i] |= tmp_b[i];
203 #define DIFF_XDL_TST(opts, flag) ((opts)->xdl_opts & XDF_##flag)
204 #define DIFF_XDL_SET(opts, flag) ((opts)->xdl_opts |= XDF_##flag)
205 #define DIFF_XDL_CLR(opts, flag) ((opts)->xdl_opts &= ~XDF_##flag)
207 #define DIFF_WITH_ALG(opts, flag) (((opts)->xdl_opts & ~XDF_DIFF_ALGORITHM_MASK) | XDF_##flag)
209 enum diff_words_type {
210 DIFF_WORDS_NONE = 0,
211 DIFF_WORDS_PORCELAIN,
212 DIFF_WORDS_PLAIN,
213 DIFF_WORDS_COLOR
216 enum diff_submodule_format {
217 DIFF_SUBMODULE_SHORT = 0,
218 DIFF_SUBMODULE_LOG,
219 DIFF_SUBMODULE_INLINE_DIFF
223 * the set of options the calling program wants to affect the operation of
224 * diffcore library with.
226 struct diff_options {
227 const char *orderfile;
230 * A constant string (can and typically does contain newlines to look for
231 * a block of text, not just a single line) to filter out the filepairs
232 * that do not change the number of strings contained in its preimage and
233 * postimage of the diff_queue.
235 const char *pickaxe;
237 const char *single_follow;
238 const char *a_prefix, *b_prefix;
239 const char *line_prefix;
240 size_t line_prefix_length;
243 * collection of boolean options that affects the operation, but some do
244 * not have anything to do with the diffcore library.
246 struct diff_flags flags;
248 /* diff-filter bits */
249 unsigned int filter;
251 int use_color;
253 /* Number of context lines to generate in patch output. */
254 int context;
256 int interhunkcontext;
258 /* Affects the way detection logic for complete rewrites, renames and
259 * copies.
261 int break_opt;
262 int detect_rename;
264 int irreversible_delete;
265 int skip_stat_unmatch;
266 int line_termination;
268 /* The output format used when `diff_flush()` is run. */
269 int output_format;
271 unsigned pickaxe_opts;
273 /* Affects the way detection logic for complete rewrites, renames and
274 * copies.
276 int rename_score;
277 int rename_limit;
279 int needed_rename_limit;
280 int degraded_cc_to_c;
281 int show_rename_progress;
282 int dirstat_permille;
283 int setup;
285 /* Number of hexdigits to abbreviate raw format output to. */
286 int abbrev;
288 int ita_invisible_in_index;
289 /* white-space error highlighting */
290 #define WSEH_NEW (1<<12)
291 #define WSEH_CONTEXT (1<<13)
292 #define WSEH_OLD (1<<14)
293 unsigned ws_error_highlight;
294 const char *prefix;
295 int prefix_length;
296 const char *stat_sep;
297 int xdl_opts;
299 /* see Documentation/diff-options.txt */
300 char **anchors;
301 size_t anchors_nr, anchors_alloc;
303 int stat_width;
304 int stat_name_width;
305 int stat_graph_width;
306 int stat_count;
307 const char *word_regex;
308 enum diff_words_type word_diff;
309 enum diff_submodule_format submodule_format;
311 struct oidset *objfind;
313 /* this is set by diffcore for DIFF_FORMAT_PATCH */
314 int found_changes;
316 /* to support internal diff recursion by --follow hack*/
317 int found_follow;
319 /* Callback which allows tweaking the options in diff_setup_done(). */
320 void (*set_default)(struct diff_options *);
322 FILE *file;
323 int close_file;
325 #define OUTPUT_INDICATOR_NEW 0
326 #define OUTPUT_INDICATOR_OLD 1
327 #define OUTPUT_INDICATOR_CONTEXT 2
328 char output_indicators[3];
330 struct pathspec pathspec;
331 pathchange_fn_t pathchange;
332 change_fn_t change;
333 add_remove_fn_t add_remove;
334 void *change_fn_data;
335 diff_format_fn_t format_callback;
336 void *format_callback_data;
337 diff_prefix_fn_t output_prefix;
338 void *output_prefix_data;
340 int diff_path_counter;
342 struct emitted_diff_symbols *emitted_symbols;
343 enum {
344 COLOR_MOVED_NO = 0,
345 COLOR_MOVED_PLAIN = 1,
346 COLOR_MOVED_BLOCKS = 2,
347 COLOR_MOVED_ZEBRA = 3,
348 COLOR_MOVED_ZEBRA_DIM = 4,
349 } color_moved;
350 #define COLOR_MOVED_DEFAULT COLOR_MOVED_ZEBRA
351 #define COLOR_MOVED_MIN_ALNUM_COUNT 20
353 /* XDF_WHITESPACE_FLAGS regarding block detection are set at 2, 3, 4 */
354 #define COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE (1<<5)
355 #define COLOR_MOVED_WS_ERROR (1<<0)
356 unsigned color_moved_ws_handling;
358 struct repository *repo;
359 struct option *parseopts;
362 unsigned diff_filter_bit(char status);
364 void diff_emit_submodule_del(struct diff_options *o, const char *line);
365 void diff_emit_submodule_add(struct diff_options *o, const char *line);
366 void diff_emit_submodule_untracked(struct diff_options *o, const char *path);
367 void diff_emit_submodule_modified(struct diff_options *o, const char *path);
368 void diff_emit_submodule_header(struct diff_options *o, const char *header);
369 void diff_emit_submodule_error(struct diff_options *o, const char *err);
370 void diff_emit_submodule_pipethrough(struct diff_options *o,
371 const char *line, int len);
373 struct diffstat_t {
374 int nr;
375 int alloc;
376 struct diffstat_file {
377 char *from_name;
378 char *name;
379 char *print_name;
380 const char *comments;
381 unsigned is_unmerged:1;
382 unsigned is_binary:1;
383 unsigned is_renamed:1;
384 unsigned is_interesting:1;
385 uintmax_t added, deleted;
386 } **files;
389 enum color_diff {
390 DIFF_RESET = 0,
391 DIFF_CONTEXT = 1,
392 DIFF_METAINFO = 2,
393 DIFF_FRAGINFO = 3,
394 DIFF_FILE_OLD = 4,
395 DIFF_FILE_NEW = 5,
396 DIFF_COMMIT = 6,
397 DIFF_WHITESPACE = 7,
398 DIFF_FUNCINFO = 8,
399 DIFF_FILE_OLD_MOVED = 9,
400 DIFF_FILE_OLD_MOVED_ALT = 10,
401 DIFF_FILE_OLD_MOVED_DIM = 11,
402 DIFF_FILE_OLD_MOVED_ALT_DIM = 12,
403 DIFF_FILE_NEW_MOVED = 13,
404 DIFF_FILE_NEW_MOVED_ALT = 14,
405 DIFF_FILE_NEW_MOVED_DIM = 15,
406 DIFF_FILE_NEW_MOVED_ALT_DIM = 16,
407 DIFF_CONTEXT_DIM = 17,
408 DIFF_FILE_OLD_DIM = 18,
409 DIFF_FILE_NEW_DIM = 19,
410 DIFF_CONTEXT_BOLD = 20,
411 DIFF_FILE_OLD_BOLD = 21,
412 DIFF_FILE_NEW_BOLD = 22,
415 const char *diff_get_color(int diff_use_color, enum color_diff ix);
416 #define diff_get_color_opt(o, ix) \
417 diff_get_color((o)->use_color, ix)
420 const char *diff_line_prefix(struct diff_options *);
423 extern const char mime_boundary_leader[];
425 struct combine_diff_path *diff_tree_paths(
426 struct combine_diff_path *p, const struct object_id *oid,
427 const struct object_id **parents_oid, int nparent,
428 struct strbuf *base, struct diff_options *opt);
429 int diff_tree_oid(const struct object_id *old_oid,
430 const struct object_id *new_oid,
431 const char *base, struct diff_options *opt);
432 int diff_root_tree_oid(const struct object_id *new_oid, const char *base,
433 struct diff_options *opt);
435 struct combine_diff_path {
436 struct combine_diff_path *next;
437 char *path;
438 unsigned int mode;
439 struct object_id oid;
440 struct combine_diff_parent {
441 char status;
442 unsigned int mode;
443 struct object_id oid;
444 struct strbuf path;
445 } parent[FLEX_ARRAY];
447 #define combine_diff_path_size(n, l) \
448 st_add4(sizeof(struct combine_diff_path), (l), 1, \
449 st_mult(sizeof(struct combine_diff_parent), (n)))
451 void show_combined_diff(struct combine_diff_path *elem, int num_parent,
452 int dense, struct rev_info *);
454 void diff_tree_combined(const struct object_id *oid, const struct oid_array *parents, int dense, struct rev_info *rev);
456 void diff_tree_combined_merge(const struct commit *commit, int dense, struct rev_info *rev);
458 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b);
460 int diff_can_quit_early(struct diff_options *);
462 void diff_addremove(struct diff_options *,
463 int addremove,
464 unsigned mode,
465 const struct object_id *oid,
466 int oid_valid,
467 const char *fullpath, unsigned dirty_submodule);
469 void diff_change(struct diff_options *,
470 unsigned mode1, unsigned mode2,
471 const struct object_id *old_oid,
472 const struct object_id *new_oid,
473 int old_oid_valid, int new_oid_valid,
474 const char *fullpath,
475 unsigned dirty_submodule1, unsigned dirty_submodule2);
477 struct diff_filepair *diff_unmerge(struct diff_options *, const char *path);
479 void compute_diffstat(struct diff_options *options, struct diffstat_t *diffstat,
480 struct diff_queue_struct *q);
481 void free_diffstat_info(struct diffstat_t *diffstat);
483 #define DIFF_SETUP_REVERSE 1
484 #define DIFF_SETUP_USE_SIZE_CACHE 4
487 * Poor man's alternative to parse-option, to allow both stuck form
488 * (--option=value) and separate form (--option value).
490 int parse_long_opt(const char *opt, const char **argv,
491 const char **optarg);
493 int git_diff_basic_config(const char *var, const char *value, void *cb);
494 int git_diff_heuristic_config(const char *var, const char *value, void *cb);
495 void init_diff_ui_defaults(void);
496 int git_diff_ui_config(const char *var, const char *value, void *cb);
497 #ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
498 #define diff_setup(diffopts) repo_diff_setup(the_repository, diffopts)
499 #endif
500 void repo_diff_setup(struct repository *, struct diff_options *);
501 int diff_opt_parse(struct diff_options *, const char **, int, const char *);
502 void diff_setup_done(struct diff_options *);
503 int git_config_rename(const char *var, const char *value);
505 #define DIFF_DETECT_RENAME 1
506 #define DIFF_DETECT_COPY 2
508 #define DIFF_PICKAXE_ALL 1
509 #define DIFF_PICKAXE_REGEX 2
511 #define DIFF_PICKAXE_KIND_S 4 /* traditional plumbing counter */
512 #define DIFF_PICKAXE_KIND_G 8 /* grep in the patch */
513 #define DIFF_PICKAXE_KIND_OBJFIND 16 /* specific object IDs */
515 #define DIFF_PICKAXE_KINDS_MASK (DIFF_PICKAXE_KIND_S | \
516 DIFF_PICKAXE_KIND_G | \
517 DIFF_PICKAXE_KIND_OBJFIND)
519 #define DIFF_PICKAXE_IGNORE_CASE 32
521 void diffcore_std(struct diff_options *);
522 void diffcore_fix_diff_index(void);
524 #define COMMON_DIFF_OPTIONS_HELP \
525 "\ncommon diff options:\n" \
526 " -z output diff-raw with lines terminated with NUL.\n" \
527 " -p output patch format.\n" \
528 " -u synonym for -p.\n" \
529 " --patch-with-raw\n" \
530 " output both a patch and the diff-raw format.\n" \
531 " --stat show diffstat instead of patch.\n" \
532 " --numstat show numeric diffstat instead of patch.\n" \
533 " --patch-with-stat\n" \
534 " output a patch and prepend its diffstat.\n" \
535 " --name-only show only names of changed files.\n" \
536 " --name-status show names and status of changed files.\n" \
537 " --full-index show full object name on index lines.\n" \
538 " --abbrev=<n> abbreviate object names in diff-tree header and diff-raw.\n" \
539 " -R swap input file pairs.\n" \
540 " -B detect complete rewrites.\n" \
541 " -M detect renames.\n" \
542 " -C detect copies.\n" \
543 " --find-copies-harder\n" \
544 " try unchanged files as candidate for copy detection.\n" \
545 " -l<n> limit rename attempts up to <n> paths.\n" \
546 " -O<file> reorder diffs according to the <file>.\n" \
547 " -S<string> find filepair whose only one side contains the string.\n" \
548 " --pickaxe-all\n" \
549 " show all files diff when -S is used and hit is found.\n" \
550 " -a --text treat all files as text.\n"
552 int diff_queue_is_empty(void);
553 void diff_flush(struct diff_options*);
554 void diff_warn_rename_limit(const char *varname, int needed, int degraded_cc);
556 /* diff-raw status letters */
557 #define DIFF_STATUS_ADDED 'A'
558 #define DIFF_STATUS_COPIED 'C'
559 #define DIFF_STATUS_DELETED 'D'
560 #define DIFF_STATUS_MODIFIED 'M'
561 #define DIFF_STATUS_RENAMED 'R'
562 #define DIFF_STATUS_TYPE_CHANGED 'T'
563 #define DIFF_STATUS_UNKNOWN 'X'
564 #define DIFF_STATUS_UNMERGED 'U'
566 /* these are not diff-raw status letters proper, but used by
567 * diffcore-filter insn to specify additional restrictions.
569 #define DIFF_STATUS_FILTER_AON '*'
570 #define DIFF_STATUS_FILTER_BROKEN 'B'
573 * This is different from find_unique_abbrev() in that
574 * it stuffs the result with dots for alignment.
576 const char *diff_aligned_abbrev(const struct object_id *sha1, int);
578 /* do not report anything on removed paths */
579 #define DIFF_SILENT_ON_REMOVED 01
580 /* report racily-clean paths as modified */
581 #define DIFF_RACY_IS_MODIFIED 02
582 int run_diff_files(struct rev_info *revs, unsigned int option);
583 int run_diff_index(struct rev_info *revs, int cached);
585 int do_diff_cache(const struct object_id *, struct diff_options *);
586 int diff_flush_patch_id(struct diff_options *, struct object_id *, int, int);
587 void flush_one_hunk(struct object_id *result, git_hash_ctx *ctx);
589 int diff_result_code(struct diff_options *, int);
591 int diff_no_index(struct rev_info *,
592 int implicit_no_index, int, const char **);
594 int index_differs_from(struct repository *r, const char *def,
595 const struct diff_flags *flags,
596 int ita_invisible_in_index);
599 * Fill the contents of the filespec "df", respecting any textconv defined by
600 * its userdiff driver. The "driver" parameter must come from a
601 * previous call to get_textconv(), and therefore should either be NULL or have
602 * textconv enabled.
604 * Note that the memory ownership of the resulting buffer depends on whether
605 * the driver field is NULL. If it is, then the memory belongs to the filespec
606 * struct. If it is non-NULL, then "outbuf" points to a newly allocated buffer
607 * that should be freed by the caller.
609 size_t fill_textconv(struct repository *r,
610 struct userdiff_driver *driver,
611 struct diff_filespec *df,
612 char **outbuf);
615 * Look up the userdiff driver for the given filespec, and return it if
616 * and only if it has textconv enabled (otherwise return NULL). The result
617 * can be passed to fill_textconv().
619 struct userdiff_driver *get_textconv(struct repository *r,
620 struct diff_filespec *one);
623 * Prepare diff_filespec and convert it using diff textconv API
624 * if the textconv driver exists.
625 * Return 1 if the conversion succeeds, 0 otherwise.
627 int textconv_object(struct repository *repo,
628 const char *path,
629 unsigned mode,
630 const struct object_id *oid, int oid_valid,
631 char **buf, unsigned long *buf_size);
633 int parse_rename_score(const char **cp_p);
635 long parse_algorithm_value(const char *value);
637 void print_stat_summary(FILE *fp, int files,
638 int insertions, int deletions);
639 void setup_diff_pager(struct diff_options *);
641 #endif /* DIFF_H */