The sixth batch for 2.26
[git.git] / graph.c
blob4fb25ad464db5778262936cdcc97b5088abc7678
1 #include "cache.h"
2 #include "config.h"
3 #include "commit.h"
4 #include "color.h"
5 #include "graph.h"
6 #include "revision.h"
7 #include "argv-array.h"
9 /* Internal API */
12 * Output a padding line in the graph.
13 * This is similar to graph_next_line(). However, it is guaranteed to
14 * never print the current commit line. Instead, if the commit line is
15 * next, it will simply output a line of vertical padding, extending the
16 * branch lines downwards, but leaving them otherwise unchanged.
18 static void graph_padding_line(struct git_graph *graph, struct strbuf *sb);
21 * Print a strbuf. If the graph is non-NULL, all lines but the first will be
22 * prefixed with the graph output.
24 * If the strbuf ends with a newline, the output will end after this
25 * newline. A new graph line will not be printed after the final newline.
26 * If the strbuf is empty, no output will be printed.
28 * Since the first line will not include the graph output, the caller is
29 * responsible for printing this line's graph (perhaps via
30 * graph_show_commit() or graph_show_oneline()) before calling
31 * graph_show_strbuf().
33 * Note that unlike some other graph display functions, you must pass the file
34 * handle directly. It is assumed that this is the same file handle as the
35 * file specified by the graph diff options. This is necessary so that
36 * graph_show_strbuf can be called even with a NULL graph.
37 * If a NULL graph is supplied, the strbuf is printed as-is.
39 static void graph_show_strbuf(struct git_graph *graph,
40 FILE *file,
41 struct strbuf const *sb);
44 * TODO:
45 * - Limit the number of columns, similar to the way gitk does.
46 * If we reach more than a specified number of columns, omit
47 * sections of some columns.
50 struct column {
52 * The parent commit of this column.
54 struct commit *commit;
56 * The color to (optionally) print this column in. This is an
57 * index into column_colors.
59 unsigned short color;
62 enum graph_state {
63 GRAPH_PADDING,
64 GRAPH_SKIP,
65 GRAPH_PRE_COMMIT,
66 GRAPH_COMMIT,
67 GRAPH_POST_MERGE,
68 GRAPH_COLLAPSING
71 static void graph_show_line_prefix(const struct diff_options *diffopt)
73 if (!diffopt || !diffopt->line_prefix)
74 return;
76 fwrite(diffopt->line_prefix,
77 sizeof(char),
78 diffopt->line_prefix_length,
79 diffopt->file);
82 static const char **column_colors;
83 static unsigned short column_colors_max;
85 static void parse_graph_colors_config(struct argv_array *colors, const char *string)
87 const char *end, *start;
89 start = string;
90 end = string + strlen(string);
91 while (start < end) {
92 const char *comma = strchrnul(start, ',');
93 char color[COLOR_MAXLEN];
95 if (!color_parse_mem(start, comma - start, color))
96 argv_array_push(colors, color);
97 else
98 warning(_("ignore invalid color '%.*s' in log.graphColors"),
99 (int)(comma - start), start);
100 start = comma + 1;
102 argv_array_push(colors, GIT_COLOR_RESET);
105 void graph_set_column_colors(const char **colors, unsigned short colors_max)
107 column_colors = colors;
108 column_colors_max = colors_max;
111 static const char *column_get_color_code(unsigned short color)
113 return column_colors[color];
116 struct graph_line {
117 struct strbuf *buf;
118 size_t width;
121 static inline void graph_line_addch(struct graph_line *line, int c)
123 strbuf_addch(line->buf, c);
124 line->width++;
127 static inline void graph_line_addchars(struct graph_line *line, int c, size_t n)
129 strbuf_addchars(line->buf, c, n);
130 line->width += n;
133 static inline void graph_line_addstr(struct graph_line *line, const char *s)
135 strbuf_addstr(line->buf, s);
136 line->width += strlen(s);
139 static inline void graph_line_addcolor(struct graph_line *line, unsigned short color)
141 strbuf_addstr(line->buf, column_get_color_code(color));
144 static void graph_line_write_column(struct graph_line *line, const struct column *c,
145 char col_char)
147 if (c->color < column_colors_max)
148 graph_line_addcolor(line, c->color);
149 graph_line_addch(line, col_char);
150 if (c->color < column_colors_max)
151 graph_line_addcolor(line, column_colors_max);
154 struct git_graph {
156 * The commit currently being processed
158 struct commit *commit;
159 /* The rev-info used for the current traversal */
160 struct rev_info *revs;
162 * The number of interesting parents that this commit has.
164 * Note that this is not the same as the actual number of parents.
165 * This count excludes parents that won't be printed in the graph
166 * output, as determined by graph_is_interesting().
168 int num_parents;
170 * The width of the graph output for this commit.
171 * All rows for this commit are padded to this width, so that
172 * messages printed after the graph output are aligned.
174 int width;
176 * The next expansion row to print
177 * when state is GRAPH_PRE_COMMIT
179 int expansion_row;
181 * The current output state.
182 * This tells us what kind of line graph_next_line() should output.
184 enum graph_state state;
186 * The output state for the previous line of output.
187 * This is primarily used to determine how the first merge line
188 * should appear, based on the last line of the previous commit.
190 enum graph_state prev_state;
192 * The index of the column that refers to this commit.
194 * If none of the incoming columns refer to this commit,
195 * this will be equal to num_columns.
197 int commit_index;
199 * The commit_index for the previously displayed commit.
201 * This is used to determine how the first line of a merge
202 * graph output should appear, based on the last line of the
203 * previous commit.
205 int prev_commit_index;
207 * Which layout variant to use to display merge commits. If the
208 * commit's first parent is known to be in a column to the left of the
209 * merge, then this value is 0 and we use the layout on the left.
210 * Otherwise, the value is 1 and the layout on the right is used. This
211 * field tells us how many columns the first parent occupies.
213 * 0) 1)
215 * | | | *-. | | *---.
216 * | |_|/|\ \ | | |\ \ \
217 * |/| | | | | | | | | | *
219 int merge_layout;
221 * The number of columns added to the graph by the current commit. For
222 * 2-way and octopus merges, this is usually one less than the
223 * number of parents:
225 * | | | | | \
226 * | * | | *---. \
227 * | |\ \ | |\ \ \ \
228 * | | | | | | | | | |
230 * num_parents: 2 num_parents: 4
231 * edges_added: 1 edges_added: 3
233 * For left-skewed merges, the first parent fuses with its neighbor and
234 * so one less column is added:
236 * | | | | | \
237 * | * | | *-. \
238 * |/| | |/|\ \ \
239 * | | | | | | | |
241 * num_parents: 2 num_parents: 4
242 * edges_added: 0 edges_added: 2
244 * This number determines how edges to the right of the merge are
245 * displayed in commit and post-merge lines; if no columns have been
246 * added then a vertical line should be used where a right-tracking
247 * line would otherwise be used.
249 * | * \ | * |
250 * | |\ \ |/| |
251 * | | * \ | * |
253 int edges_added;
255 * The number of columns added by the previous commit, which is used to
256 * smooth edges appearing to the right of a commit in a commit line
257 * following a post-merge line.
259 int prev_edges_added;
261 * The maximum number of columns that can be stored in the columns
262 * and new_columns arrays. This is also half the number of entries
263 * that can be stored in the mapping and old_mapping arrays.
265 int column_capacity;
267 * The number of columns (also called "branch lines" in some places)
269 int num_columns;
271 * The number of columns in the new_columns array
273 int num_new_columns;
275 * The number of entries in the mapping array
277 int mapping_size;
279 * The column state before we output the current commit.
281 struct column *columns;
283 * The new column state after we output the current commit.
284 * Only valid when state is GRAPH_COLLAPSING.
286 struct column *new_columns;
288 * An array that tracks the current state of each
289 * character in the output line during state GRAPH_COLLAPSING.
290 * Each entry is -1 if this character is empty, or a non-negative
291 * integer if the character contains a branch line. The value of
292 * the integer indicates the target position for this branch line.
293 * (I.e., this array maps the current column positions to their
294 * desired positions.)
296 * The maximum capacity of this array is always
297 * sizeof(int) * 2 * column_capacity.
299 int *mapping;
301 * A copy of the contents of the mapping array from the last commit,
302 * which we use to improve the display of columns that are tracking
303 * from right to left through a commit line. We also use this to
304 * avoid allocating a fresh array when we compute the next mapping.
306 int *old_mapping;
308 * The current default column color being used. This is
309 * stored as an index into the array column_colors.
311 unsigned short default_column_color;
314 static struct strbuf *diff_output_prefix_callback(struct diff_options *opt, void *data)
316 struct git_graph *graph = data;
317 static struct strbuf msgbuf = STRBUF_INIT;
319 assert(opt);
321 strbuf_reset(&msgbuf);
322 if (opt->line_prefix)
323 strbuf_add(&msgbuf, opt->line_prefix,
324 opt->line_prefix_length);
325 if (graph)
326 graph_padding_line(graph, &msgbuf);
327 return &msgbuf;
330 static const struct diff_options *default_diffopt;
332 void graph_setup_line_prefix(struct diff_options *diffopt)
334 default_diffopt = diffopt;
336 /* setup an output prefix callback if necessary */
337 if (diffopt && !diffopt->output_prefix)
338 diffopt->output_prefix = diff_output_prefix_callback;
342 struct git_graph *graph_init(struct rev_info *opt)
344 struct git_graph *graph = xmalloc(sizeof(struct git_graph));
346 if (!column_colors) {
347 char *string;
348 if (git_config_get_string("log.graphcolors", &string)) {
349 /* not configured -- use default */
350 graph_set_column_colors(column_colors_ansi,
351 column_colors_ansi_max);
352 } else {
353 static struct argv_array custom_colors = ARGV_ARRAY_INIT;
354 argv_array_clear(&custom_colors);
355 parse_graph_colors_config(&custom_colors, string);
356 free(string);
357 /* graph_set_column_colors takes a max-index, not a count */
358 graph_set_column_colors(custom_colors.argv,
359 custom_colors.argc - 1);
363 graph->commit = NULL;
364 graph->revs = opt;
365 graph->num_parents = 0;
366 graph->expansion_row = 0;
367 graph->state = GRAPH_PADDING;
368 graph->prev_state = GRAPH_PADDING;
369 graph->commit_index = 0;
370 graph->prev_commit_index = 0;
371 graph->merge_layout = 0;
372 graph->edges_added = 0;
373 graph->prev_edges_added = 0;
374 graph->num_columns = 0;
375 graph->num_new_columns = 0;
376 graph->mapping_size = 0;
378 * Start the column color at the maximum value, since we'll
379 * always increment it for the first commit we output.
380 * This way we start at 0 for the first commit.
382 graph->default_column_color = column_colors_max - 1;
385 * Allocate a reasonably large default number of columns
386 * We'll automatically grow columns later if we need more room.
388 graph->column_capacity = 30;
389 ALLOC_ARRAY(graph->columns, graph->column_capacity);
390 ALLOC_ARRAY(graph->new_columns, graph->column_capacity);
391 ALLOC_ARRAY(graph->mapping, 2 * graph->column_capacity);
392 ALLOC_ARRAY(graph->old_mapping, 2 * graph->column_capacity);
395 * The diff output prefix callback, with this we can make
396 * all the diff output to align with the graph lines.
398 opt->diffopt.output_prefix = diff_output_prefix_callback;
399 opt->diffopt.output_prefix_data = graph;
401 return graph;
404 static void graph_update_state(struct git_graph *graph, enum graph_state s)
406 graph->prev_state = graph->state;
407 graph->state = s;
410 static void graph_ensure_capacity(struct git_graph *graph, int num_columns)
412 if (graph->column_capacity >= num_columns)
413 return;
415 do {
416 graph->column_capacity *= 2;
417 } while (graph->column_capacity < num_columns);
419 REALLOC_ARRAY(graph->columns, graph->column_capacity);
420 REALLOC_ARRAY(graph->new_columns, graph->column_capacity);
421 REALLOC_ARRAY(graph->mapping, graph->column_capacity * 2);
422 REALLOC_ARRAY(graph->old_mapping, graph->column_capacity * 2);
426 * Returns 1 if the commit will be printed in the graph output,
427 * and 0 otherwise.
429 static int graph_is_interesting(struct git_graph *graph, struct commit *commit)
432 * If revs->boundary is set, commits whose children have
433 * been shown are always interesting, even if they have the
434 * UNINTERESTING or TREESAME flags set.
436 if (graph->revs && graph->revs->boundary) {
437 if (commit->object.flags & CHILD_SHOWN)
438 return 1;
442 * Otherwise, use get_commit_action() to see if this commit is
443 * interesting
445 return get_commit_action(graph->revs, commit) == commit_show;
448 static struct commit_list *next_interesting_parent(struct git_graph *graph,
449 struct commit_list *orig)
451 struct commit_list *list;
454 * If revs->first_parent_only is set, only the first
455 * parent is interesting. None of the others are.
457 if (graph->revs->first_parent_only)
458 return NULL;
461 * Return the next interesting commit after orig
463 for (list = orig->next; list; list = list->next) {
464 if (graph_is_interesting(graph, list->item))
465 return list;
468 return NULL;
471 static struct commit_list *first_interesting_parent(struct git_graph *graph)
473 struct commit_list *parents = graph->commit->parents;
476 * If this commit has no parents, ignore it
478 if (!parents)
479 return NULL;
482 * If the first parent is interesting, return it
484 if (graph_is_interesting(graph, parents->item))
485 return parents;
488 * Otherwise, call next_interesting_parent() to get
489 * the next interesting parent
491 return next_interesting_parent(graph, parents);
494 static unsigned short graph_get_current_column_color(const struct git_graph *graph)
496 if (!want_color(graph->revs->diffopt.use_color))
497 return column_colors_max;
498 return graph->default_column_color;
502 * Update the graph's default column color.
504 static void graph_increment_column_color(struct git_graph *graph)
506 graph->default_column_color = (graph->default_column_color + 1) %
507 column_colors_max;
510 static unsigned short graph_find_commit_color(const struct git_graph *graph,
511 const struct commit *commit)
513 int i;
514 for (i = 0; i < graph->num_columns; i++) {
515 if (graph->columns[i].commit == commit)
516 return graph->columns[i].color;
518 return graph_get_current_column_color(graph);
521 static int graph_find_new_column_by_commit(struct git_graph *graph,
522 struct commit *commit)
524 int i;
525 for (i = 0; i < graph->num_new_columns; i++) {
526 if (graph->new_columns[i].commit == commit)
527 return i;
529 return -1;
532 static void graph_insert_into_new_columns(struct git_graph *graph,
533 struct commit *commit,
534 int idx)
536 int i = graph_find_new_column_by_commit(graph, commit);
537 int mapping_idx;
540 * If the commit is not already in the new_columns array, then add it
541 * and record it as being in the final column.
543 if (i < 0) {
544 i = graph->num_new_columns++;
545 graph->new_columns[i].commit = commit;
546 graph->new_columns[i].color = graph_find_commit_color(graph, commit);
549 if (graph->num_parents > 1 && idx > -1 && graph->merge_layout == -1) {
551 * If this is the first parent of a merge, choose a layout for
552 * the merge line based on whether the parent appears in a
553 * column to the left of the merge
555 int dist, shift;
557 dist = idx - i;
558 shift = (dist > 1) ? 2 * dist - 3 : 1;
560 graph->merge_layout = (dist > 0) ? 0 : 1;
561 graph->edges_added = graph->num_parents + graph->merge_layout - 2;
563 mapping_idx = graph->width + (graph->merge_layout - 1) * shift;
564 graph->width += 2 * graph->merge_layout;
566 } else if (graph->edges_added > 0 && i == graph->mapping[graph->width - 2]) {
568 * If some columns have been added by a merge, but this commit
569 * was found in the last existing column, then adjust the
570 * numbers so that the two edges immediately join, i.e.:
572 * * | * |
573 * |\ \ => |\|
574 * | |/ | *
575 * | *
577 mapping_idx = graph->width - 2;
578 graph->edges_added = -1;
579 } else {
580 mapping_idx = graph->width;
581 graph->width += 2;
584 graph->mapping[mapping_idx] = i;
587 static void graph_update_columns(struct git_graph *graph)
589 struct commit_list *parent;
590 int max_new_columns;
591 int i, seen_this, is_commit_in_columns;
594 * Swap graph->columns with graph->new_columns
595 * graph->columns contains the state for the previous commit,
596 * and new_columns now contains the state for our commit.
598 * We'll re-use the old columns array as storage to compute the new
599 * columns list for the commit after this one.
601 SWAP(graph->columns, graph->new_columns);
602 graph->num_columns = graph->num_new_columns;
603 graph->num_new_columns = 0;
606 * Now update new_columns and mapping with the information for the
607 * commit after this one.
609 * First, make sure we have enough room. At most, there will
610 * be graph->num_columns + graph->num_parents columns for the next
611 * commit.
613 max_new_columns = graph->num_columns + graph->num_parents;
614 graph_ensure_capacity(graph, max_new_columns);
617 * Clear out graph->mapping
619 graph->mapping_size = 2 * max_new_columns;
620 for (i = 0; i < graph->mapping_size; i++)
621 graph->mapping[i] = -1;
623 graph->width = 0;
624 graph->prev_edges_added = graph->edges_added;
625 graph->edges_added = 0;
628 * Populate graph->new_columns and graph->mapping
630 * Some of the parents of this commit may already be in
631 * graph->columns. If so, graph->new_columns should only contain a
632 * single entry for each such commit. graph->mapping should
633 * contain information about where each current branch line is
634 * supposed to end up after the collapsing is performed.
636 seen_this = 0;
637 is_commit_in_columns = 1;
638 for (i = 0; i <= graph->num_columns; i++) {
639 struct commit *col_commit;
640 if (i == graph->num_columns) {
641 if (seen_this)
642 break;
643 is_commit_in_columns = 0;
644 col_commit = graph->commit;
645 } else {
646 col_commit = graph->columns[i].commit;
649 if (col_commit == graph->commit) {
650 seen_this = 1;
651 graph->commit_index = i;
652 graph->merge_layout = -1;
653 for (parent = first_interesting_parent(graph);
654 parent;
655 parent = next_interesting_parent(graph, parent)) {
657 * If this is a merge, or the start of a new
658 * childless column, increment the current
659 * color.
661 if (graph->num_parents > 1 ||
662 !is_commit_in_columns) {
663 graph_increment_column_color(graph);
665 graph_insert_into_new_columns(graph, parent->item, i);
668 * We always need to increment graph->width by at
669 * least 2, even if it has no interesting parents.
670 * The current commit always takes up at least 2
671 * spaces.
673 if (graph->num_parents == 0)
674 graph->width += 2;
675 } else {
676 graph_insert_into_new_columns(graph, col_commit, -1);
681 * Shrink mapping_size to be the minimum necessary
683 while (graph->mapping_size > 1 &&
684 graph->mapping[graph->mapping_size - 1] < 0)
685 graph->mapping_size--;
688 static int graph_num_dashed_parents(struct git_graph *graph)
690 return graph->num_parents + graph->merge_layout - 3;
693 static int graph_num_expansion_rows(struct git_graph *graph)
696 * Normally, we need two expansion rows for each dashed parent line from
697 * an octopus merge:
699 * | *
700 * | |\
701 * | | \
702 * | | \
703 * | *-. \
704 * | |\ \ \
706 * If the merge is skewed to the left, then its parents occupy one less
707 * column, and we don't need as many expansion rows to route around it;
708 * in some cases that means we don't need any expansion rows at all:
710 * | *
711 * | |\
712 * | * \
713 * |/|\ \
715 return graph_num_dashed_parents(graph) * 2;
718 static int graph_needs_pre_commit_line(struct git_graph *graph)
720 return graph->num_parents >= 3 &&
721 graph->commit_index < (graph->num_columns - 1) &&
722 graph->expansion_row < graph_num_expansion_rows(graph);
725 void graph_update(struct git_graph *graph, struct commit *commit)
727 struct commit_list *parent;
730 * Set the new commit
732 graph->commit = commit;
735 * Count how many interesting parents this commit has
737 graph->num_parents = 0;
738 for (parent = first_interesting_parent(graph);
739 parent;
740 parent = next_interesting_parent(graph, parent))
742 graph->num_parents++;
746 * Store the old commit_index in prev_commit_index.
747 * graph_update_columns() will update graph->commit_index for this
748 * commit.
750 graph->prev_commit_index = graph->commit_index;
753 * Call graph_update_columns() to update
754 * columns, new_columns, and mapping.
756 graph_update_columns(graph);
758 graph->expansion_row = 0;
761 * Update graph->state.
762 * Note that we don't call graph_update_state() here, since
763 * we don't want to update graph->prev_state. No line for
764 * graph->state was ever printed.
766 * If the previous commit didn't get to the GRAPH_PADDING state,
767 * it never finished its output. Goto GRAPH_SKIP, to print out
768 * a line to indicate that portion of the graph is missing.
770 * If there are 3 or more parents, we may need to print extra rows
771 * before the commit, to expand the branch lines around it and make
772 * room for it. We need to do this only if there is a branch row
773 * (or more) to the right of this commit.
775 * If there are less than 3 parents, we can immediately print the
776 * commit line.
778 if (graph->state != GRAPH_PADDING)
779 graph->state = GRAPH_SKIP;
780 else if (graph_needs_pre_commit_line(graph))
781 graph->state = GRAPH_PRE_COMMIT;
782 else
783 graph->state = GRAPH_COMMIT;
786 static int graph_is_mapping_correct(struct git_graph *graph)
788 int i;
791 * The mapping is up to date if each entry is at its target,
792 * or is 1 greater than its target.
793 * (If it is 1 greater than the target, '/' will be printed, so it
794 * will look correct on the next row.)
796 for (i = 0; i < graph->mapping_size; i++) {
797 int target = graph->mapping[i];
798 if (target < 0)
799 continue;
800 if (target == (i / 2))
801 continue;
802 return 0;
805 return 1;
808 static void graph_pad_horizontally(struct git_graph *graph, struct graph_line *line)
811 * Add additional spaces to the end of the strbuf, so that all
812 * lines for a particular commit have the same width.
814 * This way, fields printed to the right of the graph will remain
815 * aligned for the entire commit.
817 if (line->width < graph->width)
818 graph_line_addchars(line, ' ', graph->width - line->width);
821 static void graph_output_padding_line(struct git_graph *graph,
822 struct graph_line *line)
824 int i;
827 * Output a padding row, that leaves all branch lines unchanged
829 for (i = 0; i < graph->num_new_columns; i++) {
830 graph_line_write_column(line, &graph->new_columns[i], '|');
831 graph_line_addch(line, ' ');
836 int graph_width(struct git_graph *graph)
838 return graph->width;
842 static void graph_output_skip_line(struct git_graph *graph, struct graph_line *line)
845 * Output an ellipsis to indicate that a portion
846 * of the graph is missing.
848 graph_line_addstr(line, "...");
850 if (graph_needs_pre_commit_line(graph))
851 graph_update_state(graph, GRAPH_PRE_COMMIT);
852 else
853 graph_update_state(graph, GRAPH_COMMIT);
856 static void graph_output_pre_commit_line(struct git_graph *graph,
857 struct graph_line *line)
859 int i, seen_this;
862 * This function formats a row that increases the space around a commit
863 * with multiple parents, to make room for it. It should only be
864 * called when there are 3 or more parents.
866 * We need 2 extra rows for every parent over 2.
868 assert(graph->num_parents >= 3);
871 * graph->expansion_row tracks the current expansion row we are on.
872 * It should be in the range [0, num_expansion_rows - 1]
874 assert(0 <= graph->expansion_row &&
875 graph->expansion_row < graph_num_expansion_rows(graph));
878 * Output the row
880 seen_this = 0;
881 for (i = 0; i < graph->num_columns; i++) {
882 struct column *col = &graph->columns[i];
883 if (col->commit == graph->commit) {
884 seen_this = 1;
885 graph_line_write_column(line, col, '|');
886 graph_line_addchars(line, ' ', graph->expansion_row);
887 } else if (seen_this && (graph->expansion_row == 0)) {
889 * This is the first line of the pre-commit output.
890 * If the previous commit was a merge commit and
891 * ended in the GRAPH_POST_MERGE state, all branch
892 * lines after graph->prev_commit_index were
893 * printed as "\" on the previous line. Continue
894 * to print them as "\" on this line. Otherwise,
895 * print the branch lines as "|".
897 if (graph->prev_state == GRAPH_POST_MERGE &&
898 graph->prev_commit_index < i)
899 graph_line_write_column(line, col, '\\');
900 else
901 graph_line_write_column(line, col, '|');
902 } else if (seen_this && (graph->expansion_row > 0)) {
903 graph_line_write_column(line, col, '\\');
904 } else {
905 graph_line_write_column(line, col, '|');
907 graph_line_addch(line, ' ');
911 * Increment graph->expansion_row,
912 * and move to state GRAPH_COMMIT if necessary
914 graph->expansion_row++;
915 if (!graph_needs_pre_commit_line(graph))
916 graph_update_state(graph, GRAPH_COMMIT);
919 static void graph_output_commit_char(struct git_graph *graph, struct graph_line *line)
922 * For boundary commits, print 'o'
923 * (We should only see boundary commits when revs->boundary is set.)
925 if (graph->commit->object.flags & BOUNDARY) {
926 assert(graph->revs->boundary);
927 graph_line_addch(line, 'o');
928 return;
932 * get_revision_mark() handles all other cases without assert()
934 graph_line_addstr(line, get_revision_mark(graph->revs, graph->commit));
938 * Draw the horizontal dashes of an octopus merge.
940 static void graph_draw_octopus_merge(struct git_graph *graph, struct graph_line *line)
943 * The parents of a merge commit can be arbitrarily reordered as they
944 * are mapped onto display columns, for example this is a valid merge:
946 * | | *---.
947 * | | |\ \ \
948 * | | |/ / /
949 * | |/| | /
950 * | |_|_|/
951 * |/| | |
952 * 3 1 0 2
954 * The numbers denote which parent of the merge each visual column
955 * corresponds to; we can't assume that the parents will initially
956 * display in the order given by new_columns.
958 * To find the right color for each dash, we need to consult the
959 * mapping array, starting from the column 2 places to the right of the
960 * merge commit, and use that to find out which logical column each
961 * edge will collapse to.
963 * Commits are rendered once all edges have collapsed to their correct
964 * logcial column, so commit_index gives us the right visual offset for
965 * the merge commit.
968 int i, j;
969 struct column *col;
971 int dashed_parents = graph_num_dashed_parents(graph);
973 for (i = 0; i < dashed_parents; i++) {
974 j = graph->mapping[(graph->commit_index + i + 2) * 2];
975 col = &graph->new_columns[j];
977 graph_line_write_column(line, col, '-');
978 graph_line_write_column(line, col, (i == dashed_parents - 1) ? '.' : '-');
981 return;
984 static void graph_output_commit_line(struct git_graph *graph, struct graph_line *line)
986 int seen_this = 0;
987 int i;
990 * Output the row containing this commit
991 * Iterate up to and including graph->num_columns,
992 * since the current commit may not be in any of the existing
993 * columns. (This happens when the current commit doesn't have any
994 * children that we have already processed.)
996 seen_this = 0;
997 for (i = 0; i <= graph->num_columns; i++) {
998 struct column *col = &graph->columns[i];
999 struct commit *col_commit;
1000 if (i == graph->num_columns) {
1001 if (seen_this)
1002 break;
1003 col_commit = graph->commit;
1004 } else {
1005 col_commit = graph->columns[i].commit;
1008 if (col_commit == graph->commit) {
1009 seen_this = 1;
1010 graph_output_commit_char(graph, line);
1012 if (graph->num_parents > 2)
1013 graph_draw_octopus_merge(graph, line);
1014 } else if (seen_this && (graph->edges_added > 1)) {
1015 graph_line_write_column(line, col, '\\');
1016 } else if (seen_this && (graph->edges_added == 1)) {
1018 * This is either a right-skewed 2-way merge
1019 * commit, or a left-skewed 3-way merge.
1020 * There is no GRAPH_PRE_COMMIT stage for such
1021 * merges, so this is the first line of output
1022 * for this commit. Check to see what the previous
1023 * line of output was.
1025 * If it was GRAPH_POST_MERGE, the branch line
1026 * coming into this commit may have been '\',
1027 * and not '|' or '/'. If so, output the branch
1028 * line as '\' on this line, instead of '|'. This
1029 * makes the output look nicer.
1031 if (graph->prev_state == GRAPH_POST_MERGE &&
1032 graph->prev_edges_added > 0 &&
1033 graph->prev_commit_index < i)
1034 graph_line_write_column(line, col, '\\');
1035 else
1036 graph_line_write_column(line, col, '|');
1037 } else if (graph->prev_state == GRAPH_COLLAPSING &&
1038 graph->old_mapping[2 * i + 1] == i &&
1039 graph->mapping[2 * i] < i) {
1040 graph_line_write_column(line, col, '/');
1041 } else {
1042 graph_line_write_column(line, col, '|');
1044 graph_line_addch(line, ' ');
1048 * Update graph->state
1050 if (graph->num_parents > 1)
1051 graph_update_state(graph, GRAPH_POST_MERGE);
1052 else if (graph_is_mapping_correct(graph))
1053 graph_update_state(graph, GRAPH_PADDING);
1054 else
1055 graph_update_state(graph, GRAPH_COLLAPSING);
1058 const char merge_chars[] = {'/', '|', '\\'};
1060 static void graph_output_post_merge_line(struct git_graph *graph, struct graph_line *line)
1062 int seen_this = 0;
1063 int i, j;
1065 struct commit_list *first_parent = first_interesting_parent(graph);
1066 struct column *parent_col = NULL;
1069 * Output the post-merge row
1071 for (i = 0; i <= graph->num_columns; i++) {
1072 struct column *col = &graph->columns[i];
1073 struct commit *col_commit;
1074 if (i == graph->num_columns) {
1075 if (seen_this)
1076 break;
1077 col_commit = graph->commit;
1078 } else {
1079 col_commit = col->commit;
1082 if (col_commit == graph->commit) {
1084 * Since the current commit is a merge find
1085 * the columns for the parent commits in
1086 * new_columns and use those to format the
1087 * edges.
1089 struct commit_list *parents = first_parent;
1090 int par_column;
1091 int idx = graph->merge_layout;
1092 char c;
1093 seen_this = 1;
1095 for (j = 0; j < graph->num_parents; j++) {
1096 par_column = graph_find_new_column_by_commit(graph, parents->item);
1097 assert(par_column >= 0);
1099 c = merge_chars[idx];
1100 graph_line_write_column(line, &graph->new_columns[par_column], c);
1101 if (idx == 2) {
1102 if (graph->edges_added > 0 || j < graph->num_parents - 1)
1103 graph_line_addch(line, ' ');
1104 } else {
1105 idx++;
1107 parents = next_interesting_parent(graph, parents);
1109 if (graph->edges_added == 0)
1110 graph_line_addch(line, ' ');
1112 } else if (seen_this) {
1113 if (graph->edges_added > 0)
1114 graph_line_write_column(line, col, '\\');
1115 else
1116 graph_line_write_column(line, col, '|');
1117 graph_line_addch(line, ' ');
1118 } else {
1119 graph_line_write_column(line, col, '|');
1120 if (graph->merge_layout != 0 || i != graph->commit_index - 1) {
1121 if (parent_col)
1122 graph_line_write_column(
1123 line, parent_col, '_');
1124 else
1125 graph_line_addch(line, ' ');
1129 if (col_commit == first_parent->item)
1130 parent_col = col;
1134 * Update graph->state
1136 if (graph_is_mapping_correct(graph))
1137 graph_update_state(graph, GRAPH_PADDING);
1138 else
1139 graph_update_state(graph, GRAPH_COLLAPSING);
1142 static void graph_output_collapsing_line(struct git_graph *graph, struct graph_line *line)
1144 int i;
1145 short used_horizontal = 0;
1146 int horizontal_edge = -1;
1147 int horizontal_edge_target = -1;
1150 * Swap the mapping and old_mapping arrays
1152 SWAP(graph->mapping, graph->old_mapping);
1155 * Clear out the mapping array
1157 for (i = 0; i < graph->mapping_size; i++)
1158 graph->mapping[i] = -1;
1160 for (i = 0; i < graph->mapping_size; i++) {
1161 int target = graph->old_mapping[i];
1162 if (target < 0)
1163 continue;
1166 * Since update_columns() always inserts the leftmost
1167 * column first, each branch's target location should
1168 * always be either its current location or to the left of
1169 * its current location.
1171 * We never have to move branches to the right. This makes
1172 * the graph much more legible, since whenever branches
1173 * cross, only one is moving directions.
1175 assert(target * 2 <= i);
1177 if (target * 2 == i) {
1179 * This column is already in the
1180 * correct place
1182 assert(graph->mapping[i] == -1);
1183 graph->mapping[i] = target;
1184 } else if (graph->mapping[i - 1] < 0) {
1186 * Nothing is to the left.
1187 * Move to the left by one
1189 graph->mapping[i - 1] = target;
1191 * If there isn't already an edge moving horizontally
1192 * select this one.
1194 if (horizontal_edge == -1) {
1195 int j;
1196 horizontal_edge = i;
1197 horizontal_edge_target = target;
1199 * The variable target is the index of the graph
1200 * column, and therefore target*2+3 is the
1201 * actual screen column of the first horizontal
1202 * line.
1204 for (j = (target * 2)+3; j < (i - 2); j += 2)
1205 graph->mapping[j] = target;
1207 } else if (graph->mapping[i - 1] == target) {
1209 * There is a branch line to our left
1210 * already, and it is our target. We
1211 * combine with this line, since we share
1212 * the same parent commit.
1214 * We don't have to add anything to the
1215 * output or mapping, since the
1216 * existing branch line has already taken
1217 * care of it.
1219 } else {
1221 * There is a branch line to our left,
1222 * but it isn't our target. We need to
1223 * cross over it.
1225 * The space just to the left of this
1226 * branch should always be empty.
1228 assert(graph->mapping[i - 1] > target);
1229 assert(graph->mapping[i - 2] < 0);
1230 graph->mapping[i - 2] = target;
1232 * Mark this branch as the horizontal edge to
1233 * prevent any other edges from moving
1234 * horizontally.
1236 if (horizontal_edge == -1) {
1237 int j;
1238 horizontal_edge_target = target;
1239 horizontal_edge = i - 1;
1241 for (j = (target * 2) + 3; j < (i - 2); j += 2)
1242 graph->mapping[j] = target;
1248 * Copy the current mapping array into old_mapping
1250 COPY_ARRAY(graph->old_mapping, graph->mapping, graph->mapping_size);
1253 * The new mapping may be 1 smaller than the old mapping
1255 if (graph->mapping[graph->mapping_size - 1] < 0)
1256 graph->mapping_size--;
1259 * Output out a line based on the new mapping info
1261 for (i = 0; i < graph->mapping_size; i++) {
1262 int target = graph->mapping[i];
1263 if (target < 0)
1264 graph_line_addch(line, ' ');
1265 else if (target * 2 == i)
1266 graph_line_write_column(line, &graph->new_columns[target], '|');
1267 else if (target == horizontal_edge_target &&
1268 i != horizontal_edge - 1) {
1270 * Set the mappings for all but the
1271 * first segment to -1 so that they
1272 * won't continue into the next line.
1274 if (i != (target * 2)+3)
1275 graph->mapping[i] = -1;
1276 used_horizontal = 1;
1277 graph_line_write_column(line, &graph->new_columns[target], '_');
1278 } else {
1279 if (used_horizontal && i < horizontal_edge)
1280 graph->mapping[i] = -1;
1281 graph_line_write_column(line, &graph->new_columns[target], '/');
1287 * If graph->mapping indicates that all of the branch lines
1288 * are already in the correct positions, we are done.
1289 * Otherwise, we need to collapse some branch lines together.
1291 if (graph_is_mapping_correct(graph))
1292 graph_update_state(graph, GRAPH_PADDING);
1295 int graph_next_line(struct git_graph *graph, struct strbuf *sb)
1297 int shown_commit_line = 0;
1298 struct graph_line line = { .buf = sb, .width = 0 };
1301 * We could conceivable be called with a NULL commit
1302 * if our caller has a bug, and invokes graph_next_line()
1303 * immediately after graph_init(), without first calling
1304 * graph_update(). Return without outputting anything in this
1305 * case.
1307 if (!graph->commit)
1308 return -1;
1310 switch (graph->state) {
1311 case GRAPH_PADDING:
1312 graph_output_padding_line(graph, &line);
1313 break;
1314 case GRAPH_SKIP:
1315 graph_output_skip_line(graph, &line);
1316 break;
1317 case GRAPH_PRE_COMMIT:
1318 graph_output_pre_commit_line(graph, &line);
1319 break;
1320 case GRAPH_COMMIT:
1321 graph_output_commit_line(graph, &line);
1322 shown_commit_line = 1;
1323 break;
1324 case GRAPH_POST_MERGE:
1325 graph_output_post_merge_line(graph, &line);
1326 break;
1327 case GRAPH_COLLAPSING:
1328 graph_output_collapsing_line(graph, &line);
1329 break;
1332 graph_pad_horizontally(graph, &line);
1333 return shown_commit_line;
1336 static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
1338 int i;
1339 struct graph_line line = { .buf = sb, .width = 0 };
1341 if (graph->state != GRAPH_COMMIT) {
1342 graph_next_line(graph, sb);
1343 return;
1347 * Output the row containing this commit
1348 * Iterate up to and including graph->num_columns,
1349 * since the current commit may not be in any of the existing
1350 * columns. (This happens when the current commit doesn't have any
1351 * children that we have already processed.)
1353 for (i = 0; i < graph->num_columns; i++) {
1354 struct column *col = &graph->columns[i];
1356 graph_line_write_column(&line, col, '|');
1358 if (col->commit == graph->commit && graph->num_parents > 2) {
1359 int len = (graph->num_parents - 2) * 2;
1360 graph_line_addchars(&line, ' ', len);
1361 } else {
1362 graph_line_addch(&line, ' ');
1366 graph_pad_horizontally(graph, &line);
1369 * Update graph->prev_state since we have output a padding line
1371 graph->prev_state = GRAPH_PADDING;
1374 int graph_is_commit_finished(struct git_graph const *graph)
1376 return (graph->state == GRAPH_PADDING);
1379 void graph_show_commit(struct git_graph *graph)
1381 struct strbuf msgbuf = STRBUF_INIT;
1382 int shown_commit_line = 0;
1384 graph_show_line_prefix(default_diffopt);
1386 if (!graph)
1387 return;
1390 * When showing a diff of a merge against each of its parents, we
1391 * are called once for each parent without graph_update having been
1392 * called. In this case, simply output a single padding line.
1394 if (graph_is_commit_finished(graph)) {
1395 graph_show_padding(graph);
1396 shown_commit_line = 1;
1399 while (!shown_commit_line && !graph_is_commit_finished(graph)) {
1400 shown_commit_line = graph_next_line(graph, &msgbuf);
1401 fwrite(msgbuf.buf, sizeof(char), msgbuf.len,
1402 graph->revs->diffopt.file);
1403 if (!shown_commit_line) {
1404 putc('\n', graph->revs->diffopt.file);
1405 graph_show_line_prefix(&graph->revs->diffopt);
1407 strbuf_setlen(&msgbuf, 0);
1410 strbuf_release(&msgbuf);
1413 void graph_show_oneline(struct git_graph *graph)
1415 struct strbuf msgbuf = STRBUF_INIT;
1417 graph_show_line_prefix(default_diffopt);
1419 if (!graph)
1420 return;
1422 graph_next_line(graph, &msgbuf);
1423 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, graph->revs->diffopt.file);
1424 strbuf_release(&msgbuf);
1427 void graph_show_padding(struct git_graph *graph)
1429 struct strbuf msgbuf = STRBUF_INIT;
1431 graph_show_line_prefix(default_diffopt);
1433 if (!graph)
1434 return;
1436 graph_padding_line(graph, &msgbuf);
1437 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, graph->revs->diffopt.file);
1438 strbuf_release(&msgbuf);
1441 int graph_show_remainder(struct git_graph *graph)
1443 struct strbuf msgbuf = STRBUF_INIT;
1444 int shown = 0;
1446 graph_show_line_prefix(default_diffopt);
1448 if (!graph)
1449 return 0;
1451 if (graph_is_commit_finished(graph))
1452 return 0;
1454 for (;;) {
1455 graph_next_line(graph, &msgbuf);
1456 fwrite(msgbuf.buf, sizeof(char), msgbuf.len,
1457 graph->revs->diffopt.file);
1458 strbuf_setlen(&msgbuf, 0);
1459 shown = 1;
1461 if (!graph_is_commit_finished(graph)) {
1462 putc('\n', graph->revs->diffopt.file);
1463 graph_show_line_prefix(&graph->revs->diffopt);
1464 } else {
1465 break;
1468 strbuf_release(&msgbuf);
1470 return shown;
1473 static void graph_show_strbuf(struct git_graph *graph,
1474 FILE *file,
1475 struct strbuf const *sb)
1477 char *p;
1480 * Print the strbuf line by line,
1481 * and display the graph info before each line but the first.
1483 p = sb->buf;
1484 while (p) {
1485 size_t len;
1486 char *next_p = strchr(p, '\n');
1487 if (next_p) {
1488 next_p++;
1489 len = next_p - p;
1490 } else {
1491 len = (sb->buf + sb->len) - p;
1493 fwrite(p, sizeof(char), len, file);
1494 if (next_p && *next_p != '\0')
1495 graph_show_oneline(graph);
1496 p = next_p;
1500 void graph_show_commit_msg(struct git_graph *graph,
1501 FILE *file,
1502 struct strbuf const *sb)
1504 int newline_terminated;
1507 * Show the commit message
1509 graph_show_strbuf(graph, file, sb);
1511 if (!graph)
1512 return;
1514 newline_terminated = (sb->len && sb->buf[sb->len - 1] == '\n');
1517 * If there is more output needed for this commit, show it now
1519 if (!graph_is_commit_finished(graph)) {
1521 * If sb doesn't have a terminating newline, print one now,
1522 * so we can start the remainder of the graph output on a
1523 * new line.
1525 if (!newline_terminated)
1526 putc('\n', file);
1528 graph_show_remainder(graph);
1531 * If sb ends with a newline, our output should too.
1533 if (newline_terminated)
1534 putc('\n', file);