color.c: trim leading spaces in color_parse_mem()
[git/git.git] / graph.c
CommitLineData
c12172d2
AS
1#include "cache.h"
2#include "commit.h"
427fc5b8 3#include "color.h"
c12172d2
AS
4#include "graph.h"
5#include "diff.h"
6#include "revision.h"
7
064bfbde
NS
8/* Internal API */
9
064bfbde
NS
10/*
11 * Output a padding line in the graph.
12 * This is similar to graph_next_line(). However, it is guaranteed to
13 * never print the current commit line. Instead, if the commit line is
14 * next, it will simply output a line of vertical padding, extending the
15 * branch lines downwards, but leaving them otherwise unchanged.
16 */
17static void graph_padding_line(struct git_graph *graph, struct strbuf *sb);
18
19/*
c61008fd
JS
20 * Print a strbuf. If the graph is non-NULL, all lines but the first will be
21 * prefixed with the graph output.
064bfbde
NS
22 *
23 * If the strbuf ends with a newline, the output will end after this
24 * newline. A new graph line will not be printed after the final newline.
25 * If the strbuf is empty, no output will be printed.
26 *
3ea3c215 27 * Since the first line will not include the graph output, the caller is
064bfbde
NS
28 * responsible for printing this line's graph (perhaps via
29 * graph_show_commit() or graph_show_oneline()) before calling
30 * graph_show_strbuf().
31 */
32static void graph_show_strbuf(struct git_graph *graph, struct strbuf const *sb);
33
c12172d2
AS
34/*
35 * TODO:
c12172d2
AS
36 * - Limit the number of columns, similar to the way gitk does.
37 * If we reach more than a specified number of columns, omit
38 * sections of some columns.
c12172d2
AS
39 */
40
41struct column {
42 /*
43 * The parent commit of this column.
44 */
45 struct commit *commit;
46 /*
427fc5b8
AC
47 * The color to (optionally) print this column in. This is an
48 * index into column_colors.
c12172d2 49 */
427fc5b8 50 unsigned short color;
c12172d2
AS
51};
52
53enum graph_state {
54 GRAPH_PADDING,
55 GRAPH_SKIP,
56 GRAPH_PRE_COMMIT,
57 GRAPH_COMMIT,
58 GRAPH_POST_MERGE,
59 GRAPH_COLLAPSING
60};
61
1e3d4119
JH
62static const char **column_colors;
63static unsigned short column_colors_max;
64
ac751a0b 65void graph_set_column_colors(const char **colors, unsigned short colors_max)
1e3d4119
JH
66{
67 column_colors = colors;
68 column_colors_max = colors_max;
69}
70
71static const char *column_get_color_code(unsigned short color)
427fc5b8 72{
1e3d4119 73 return column_colors[color];
427fc5b8
AC
74}
75
76static void strbuf_write_column(struct strbuf *sb, const struct column *c,
77 char col_char)
78{
1e3d4119
JH
79 if (c->color < column_colors_max)
80 strbuf_addstr(sb, column_get_color_code(c->color));
427fc5b8 81 strbuf_addch(sb, col_char);
1e3d4119
JH
82 if (c->color < column_colors_max)
83 strbuf_addstr(sb, column_get_color_code(column_colors_max));
427fc5b8
AC
84}
85
c12172d2
AS
86struct git_graph {
87 /*
88 * The commit currently being processed
89 */
90 struct commit *commit;
7528f27d
AS
91 /* The rev-info used for the current traversal */
92 struct rev_info *revs;
c12172d2 93 /*
37a75abc
AS
94 * The number of interesting parents that this commit has.
95 *
96 * Note that this is not the same as the actual number of parents.
97 * This count excludes parents that won't be printed in the graph
98 * output, as determined by graph_is_interesting().
c12172d2
AS
99 */
100 int num_parents;
0724cb86
AS
101 /*
102 * The width of the graph output for this commit.
103 * All rows for this commit are padded to this width, so that
104 * messages printed after the graph output are aligned.
105 */
106 int width;
c12172d2
AS
107 /*
108 * The next expansion row to print
109 * when state is GRAPH_PRE_COMMIT
110 */
111 int expansion_row;
112 /*
113 * The current output state.
114 * This tells us what kind of line graph_next_line() should output.
115 */
116 enum graph_state state;
3395908e
AS
117 /*
118 * The output state for the previous line of output.
119 * This is primarily used to determine how the first merge line
120 * should appear, based on the last line of the previous commit.
121 */
122 enum graph_state prev_state;
123 /*
124 * The index of the column that refers to this commit.
125 *
126 * If none of the incoming columns refer to this commit,
127 * this will be equal to num_columns.
128 */
129 int commit_index;
130 /*
131 * The commit_index for the previously displayed commit.
132 *
133 * This is used to determine how the first line of a merge
134 * graph output should appear, based on the last line of the
135 * previous commit.
136 */
137 int prev_commit_index;
c12172d2
AS
138 /*
139 * The maximum number of columns that can be stored in the columns
140 * and new_columns arrays. This is also half the number of entries
141 * that can be stored in the mapping and new_mapping arrays.
142 */
143 int column_capacity;
144 /*
145 * The number of columns (also called "branch lines" in some places)
146 */
147 int num_columns;
148 /*
149 * The number of columns in the new_columns array
150 */
151 int num_new_columns;
152 /*
153 * The number of entries in the mapping array
154 */
155 int mapping_size;
156 /*
157 * The column state before we output the current commit.
158 */
159 struct column *columns;
160 /*
161 * The new column state after we output the current commit.
162 * Only valid when state is GRAPH_COLLAPSING.
163 */
164 struct column *new_columns;
165 /*
166 * An array that tracks the current state of each
167 * character in the output line during state GRAPH_COLLAPSING.
168 * Each entry is -1 if this character is empty, or a non-negative
169 * integer if the character contains a branch line. The value of
170 * the integer indicates the target position for this branch line.
171 * (I.e., this array maps the current column positions to their
172 * desired positions.)
173 *
174 * The maximum capacity of this array is always
175 * sizeof(int) * 2 * column_capacity.
176 */
177 int *mapping;
178 /*
179 * A temporary array for computing the next mapping state
180 * while we are outputting a mapping line. This is stored as part
181 * of the git_graph simply so we don't have to allocate a new
182 * temporary array each time we have to output a collapsing line.
183 */
184 int *new_mapping;
427fc5b8
AC
185 /*
186 * The current default column color being used. This is
187 * stored as an index into the array column_colors.
188 */
189 unsigned short default_column_color;
c12172d2
AS
190};
191
b5a4de9d
BY
192static struct strbuf *diff_output_prefix_callback(struct diff_options *opt, void *data)
193{
194 struct git_graph *graph = data;
195 static struct strbuf msgbuf = STRBUF_INIT;
196
5e71a84a 197 assert(opt);
b5a4de9d
BY
198 assert(graph);
199
5e71a84a 200 opt->output_prefix_length = graph->width;
b5a4de9d
BY
201 strbuf_reset(&msgbuf);
202 graph_padding_line(graph, &msgbuf);
203 return &msgbuf;
204}
205
7528f27d 206struct git_graph *graph_init(struct rev_info *opt)
c12172d2
AS
207{
208 struct git_graph *graph = xmalloc(sizeof(struct git_graph));
1e3d4119
JH
209
210 if (!column_colors)
211 graph_set_column_colors(column_colors_ansi,
7cd52b5b 212 column_colors_ansi_max);
1e3d4119 213
c12172d2 214 graph->commit = NULL;
7528f27d 215 graph->revs = opt;
c12172d2
AS
216 graph->num_parents = 0;
217 graph->expansion_row = 0;
218 graph->state = GRAPH_PADDING;
3395908e
AS
219 graph->prev_state = GRAPH_PADDING;
220 graph->commit_index = 0;
221 graph->prev_commit_index = 0;
c12172d2
AS
222 graph->num_columns = 0;
223 graph->num_new_columns = 0;
224 graph->mapping_size = 0;
91e50b2c
AS
225 /*
226 * Start the column color at the maximum value, since we'll
227 * always increment it for the first commit we output.
228 * This way we start at 0 for the first commit.
229 */
1e3d4119 230 graph->default_column_color = column_colors_max - 1;
c12172d2
AS
231
232 /*
233 * Allocate a reasonably large default number of columns
234 * We'll automatically grow columns later if we need more room.
235 */
236 graph->column_capacity = 30;
b32fa95f
JK
237 ALLOC_ARRAY(graph->columns, graph->column_capacity);
238 ALLOC_ARRAY(graph->new_columns, graph->column_capacity);
239 ALLOC_ARRAY(graph->mapping, 2 * graph->column_capacity);
240 ALLOC_ARRAY(graph->new_mapping, 2 * graph->column_capacity);
c12172d2 241
b5a4de9d
BY
242 /*
243 * The diff output prefix callback, with this we can make
244 * all the diff output to align with the graph lines.
245 */
246 opt->diffopt.output_prefix = diff_output_prefix_callback;
247 opt->diffopt.output_prefix_data = graph;
5e71a84a 248 opt->diffopt.output_prefix_length = 0;
b5a4de9d 249
c12172d2
AS
250 return graph;
251}
252
3395908e
AS
253static void graph_update_state(struct git_graph *graph, enum graph_state s)
254{
255 graph->prev_state = graph->state;
256 graph->state = s;
257}
258
c12172d2
AS
259static void graph_ensure_capacity(struct git_graph *graph, int num_columns)
260{
261 if (graph->column_capacity >= num_columns)
262 return;
263
264 do {
265 graph->column_capacity *= 2;
266 } while (graph->column_capacity < num_columns);
267
2756ca43
RS
268 REALLOC_ARRAY(graph->columns, graph->column_capacity);
269 REALLOC_ARRAY(graph->new_columns, graph->column_capacity);
270 REALLOC_ARRAY(graph->mapping, graph->column_capacity * 2);
271 REALLOC_ARRAY(graph->new_mapping, graph->column_capacity * 2);
c12172d2
AS
272}
273
37a75abc
AS
274/*
275 * Returns 1 if the commit will be printed in the graph output,
276 * and 0 otherwise.
277 */
3c68d67b 278static int graph_is_interesting(struct git_graph *graph, struct commit *commit)
37a75abc 279{
3c68d67b
AS
280 /*
281 * If revs->boundary is set, commits whose children have
282 * been shown are always interesting, even if they have the
283 * UNINTERESTING or TREESAME flags set.
3c68d67b
AS
284 */
285 if (graph->revs && graph->revs->boundary) {
4603ec0f 286 if (commit->object.flags & CHILD_SHOWN)
3c68d67b
AS
287 return 1;
288 }
289
37a75abc 290 /*
beb5af43
AS
291 * Otherwise, use get_commit_action() to see if this commit is
292 * interesting
37a75abc 293 */
beb5af43 294 return get_commit_action(graph->revs, commit) == commit_show;
37a75abc
AS
295}
296
a0ebe573
AS
297static struct commit_list *next_interesting_parent(struct git_graph *graph,
298 struct commit_list *orig)
299{
300 struct commit_list *list;
301
302 /*
303 * If revs->first_parent_only is set, only the first
304 * parent is interesting. None of the others are.
305 */
306 if (graph->revs->first_parent_only)
307 return NULL;
308
309 /*
310 * Return the next interesting commit after orig
311 */
312 for (list = orig->next; list; list = list->next) {
313 if (graph_is_interesting(graph, list->item))
314 return list;
315 }
316
317 return NULL;
318}
319
320static struct commit_list *first_interesting_parent(struct git_graph *graph)
321{
322 struct commit_list *parents = graph->commit->parents;
323
324 /*
325 * If this commit has no parents, ignore it
326 */
327 if (!parents)
328 return NULL;
329
330 /*
331 * If the first parent is interesting, return it
332 */
333 if (graph_is_interesting(graph, parents->item))
334 return parents;
335
336 /*
337 * Otherwise, call next_interesting_parent() to get
338 * the next interesting parent
339 */
340 return next_interesting_parent(graph, parents);
341}
342
427fc5b8
AC
343static unsigned short graph_get_current_column_color(const struct git_graph *graph)
344{
daa0c3d9 345 if (!want_color(graph->revs->diffopt.use_color))
1e3d4119 346 return column_colors_max;
427fc5b8
AC
347 return graph->default_column_color;
348}
349
350/*
351 * Update the graph's default column color.
352 */
353static void graph_increment_column_color(struct git_graph *graph)
354{
355 graph->default_column_color = (graph->default_column_color + 1) %
1e3d4119 356 column_colors_max;
427fc5b8
AC
357}
358
359static unsigned short graph_find_commit_color(const struct git_graph *graph,
360 const struct commit *commit)
361{
362 int i;
363 for (i = 0; i < graph->num_columns; i++) {
364 if (graph->columns[i].commit == commit)
365 return graph->columns[i].color;
366 }
367 return graph_get_current_column_color(graph);
368}
369
c12172d2
AS
370static void graph_insert_into_new_columns(struct git_graph *graph,
371 struct commit *commit,
372 int *mapping_index)
373{
374 int i;
375
c12172d2
AS
376 /*
377 * If the commit is already in the new_columns list, we don't need to
378 * add it. Just update the mapping correctly.
379 */
380 for (i = 0; i < graph->num_new_columns; i++) {
381 if (graph->new_columns[i].commit == commit) {
382 graph->mapping[*mapping_index] = i;
383 *mapping_index += 2;
384 return;
385 }
386 }
387
388 /*
389 * This commit isn't already in new_columns. Add it.
390 */
391 graph->new_columns[graph->num_new_columns].commit = commit;
427fc5b8 392 graph->new_columns[graph->num_new_columns].color = graph_find_commit_color(graph, commit);
c12172d2
AS
393 graph->mapping[*mapping_index] = graph->num_new_columns;
394 *mapping_index += 2;
395 graph->num_new_columns++;
396}
397
0724cb86
AS
398static void graph_update_width(struct git_graph *graph,
399 int is_commit_in_existing_columns)
400{
401 /*
402 * Compute the width needed to display the graph for this commit.
403 * This is the maximum width needed for any row. All other rows
404 * will be padded to this width.
405 *
406 * Compute the number of columns in the widest row:
407 * Count each existing column (graph->num_columns), and each new
408 * column added by this commit.
409 */
410 int max_cols = graph->num_columns + graph->num_parents;
411
412 /*
37a75abc
AS
413 * Even if the current commit has no parents to be printed, it
414 * still takes up a column for itself.
0724cb86
AS
415 */
416 if (graph->num_parents < 1)
417 max_cols++;
418
419 /*
22e5e58a 420 * We added a column for the current commit as part of
0724cb86
AS
421 * graph->num_parents. If the current commit was already in
422 * graph->columns, then we have double counted it.
423 */
424 if (is_commit_in_existing_columns)
425 max_cols--;
426
427 /*
428 * Each column takes up 2 spaces
429 */
430 graph->width = max_cols * 2;
431}
432
c12172d2
AS
433static void graph_update_columns(struct git_graph *graph)
434{
435 struct commit_list *parent;
436 struct column *tmp_columns;
437 int max_new_columns;
438 int mapping_idx;
0724cb86 439 int i, seen_this, is_commit_in_columns;
c12172d2
AS
440
441 /*
442 * Swap graph->columns with graph->new_columns
443 * graph->columns contains the state for the previous commit,
444 * and new_columns now contains the state for our commit.
445 *
446 * We'll re-use the old columns array as storage to compute the new
447 * columns list for the commit after this one.
448 */
449 tmp_columns = graph->columns;
450 graph->columns = graph->new_columns;
451 graph->num_columns = graph->num_new_columns;
452
453 graph->new_columns = tmp_columns;
454 graph->num_new_columns = 0;
455
456 /*
457 * Now update new_columns and mapping with the information for the
458 * commit after this one.
459 *
460 * First, make sure we have enough room. At most, there will
461 * be graph->num_columns + graph->num_parents columns for the next
462 * commit.
463 */
464 max_new_columns = graph->num_columns + graph->num_parents;
465 graph_ensure_capacity(graph, max_new_columns);
466
467 /*
468 * Clear out graph->mapping
469 */
470 graph->mapping_size = 2 * max_new_columns;
471 for (i = 0; i < graph->mapping_size; i++)
472 graph->mapping[i] = -1;
473
474 /*
475 * Populate graph->new_columns and graph->mapping
476 *
477 * Some of the parents of this commit may already be in
478 * graph->columns. If so, graph->new_columns should only contain a
479 * single entry for each such commit. graph->mapping should
480 * contain information about where each current branch line is
481 * supposed to end up after the collapsing is performed.
482 */
483 seen_this = 0;
484 mapping_idx = 0;
0724cb86 485 is_commit_in_columns = 1;
c12172d2
AS
486 for (i = 0; i <= graph->num_columns; i++) {
487 struct commit *col_commit;
488 if (i == graph->num_columns) {
489 if (seen_this)
490 break;
0724cb86 491 is_commit_in_columns = 0;
c12172d2
AS
492 col_commit = graph->commit;
493 } else {
494 col_commit = graph->columns[i].commit;
495 }
496
497 if (col_commit == graph->commit) {
37a75abc 498 int old_mapping_idx = mapping_idx;
c12172d2 499 seen_this = 1;
3395908e 500 graph->commit_index = i;
a0ebe573 501 for (parent = first_interesting_parent(graph);
c12172d2 502 parent;
a0ebe573 503 parent = next_interesting_parent(graph, parent)) {
427fc5b8 504 /*
91e50b2c
AS
505 * If this is a merge, or the start of a new
506 * childless column, increment the current
427fc5b8
AC
507 * color.
508 */
91e50b2c
AS
509 if (graph->num_parents > 1 ||
510 !is_commit_in_columns) {
427fc5b8 511 graph_increment_column_color(graph);
91e50b2c 512 }
c12172d2
AS
513 graph_insert_into_new_columns(graph,
514 parent->item,
515 &mapping_idx);
516 }
37a75abc
AS
517 /*
518 * We always need to increment mapping_idx by at
519 * least 2, even if it has no interesting parents.
520 * The current commit always takes up at least 2
521 * spaces.
522 */
523 if (mapping_idx == old_mapping_idx)
524 mapping_idx += 2;
c12172d2
AS
525 } else {
526 graph_insert_into_new_columns(graph, col_commit,
527 &mapping_idx);
528 }
529 }
530
531 /*
532 * Shrink mapping_size to be the minimum necessary
533 */
534 while (graph->mapping_size > 1 &&
535 graph->mapping[graph->mapping_size - 1] < 0)
536 graph->mapping_size--;
0724cb86
AS
537
538 /*
539 * Compute graph->width for this commit
540 */
541 graph_update_width(graph, is_commit_in_columns);
c12172d2
AS
542}
543
544void graph_update(struct git_graph *graph, struct commit *commit)
545{
546 struct commit_list *parent;
547
548 /*
549 * Set the new commit
550 */
551 graph->commit = commit;
552
553 /*
37a75abc 554 * Count how many interesting parents this commit has
c12172d2
AS
555 */
556 graph->num_parents = 0;
a0ebe573
AS
557 for (parent = first_interesting_parent(graph);
558 parent;
559 parent = next_interesting_parent(graph, parent))
560 {
561 graph->num_parents++;
37a75abc 562 }
c12172d2 563
3395908e
AS
564 /*
565 * Store the old commit_index in prev_commit_index.
566 * graph_update_columns() will update graph->commit_index for this
567 * commit.
568 */
569 graph->prev_commit_index = graph->commit_index;
570
c12172d2
AS
571 /*
572 * Call graph_update_columns() to update
573 * columns, new_columns, and mapping.
574 */
575 graph_update_columns(graph);
576
577 graph->expansion_row = 0;
578
579 /*
580 * Update graph->state.
3395908e
AS
581 * Note that we don't call graph_update_state() here, since
582 * we don't want to update graph->prev_state. No line for
583 * graph->state was ever printed.
c12172d2
AS
584 *
585 * If the previous commit didn't get to the GRAPH_PADDING state,
586 * it never finished its output. Goto GRAPH_SKIP, to print out
587 * a line to indicate that portion of the graph is missing.
588 *
f1979d6b
AS
589 * If there are 3 or more parents, we may need to print extra rows
590 * before the commit, to expand the branch lines around it and make
591 * room for it. We need to do this only if there is a branch row
592 * (or more) to the right of this commit.
c12172d2
AS
593 *
594 * If there are less than 3 parents, we can immediately print the
595 * commit line.
596 */
597 if (graph->state != GRAPH_PADDING)
598 graph->state = GRAPH_SKIP;
f1979d6b
AS
599 else if (graph->num_parents >= 3 &&
600 graph->commit_index < (graph->num_columns - 1))
c12172d2
AS
601 graph->state = GRAPH_PRE_COMMIT;
602 else
603 graph->state = GRAPH_COMMIT;
604}
605
606static int graph_is_mapping_correct(struct git_graph *graph)
607{
608 int i;
609
610 /*
611 * The mapping is up to date if each entry is at its target,
612 * or is 1 greater than its target.
613 * (If it is 1 greater than the target, '/' will be printed, so it
614 * will look correct on the next row.)
615 */
616 for (i = 0; i < graph->mapping_size; i++) {
617 int target = graph->mapping[i];
618 if (target < 0)
619 continue;
620 if (target == (i / 2))
621 continue;
622 return 0;
623 }
624
625 return 1;
626}
627
427fc5b8
AC
628static void graph_pad_horizontally(struct git_graph *graph, struct strbuf *sb,
629 int chars_written)
c12172d2
AS
630{
631 /*
632 * Add additional spaces to the end of the strbuf, so that all
633 * lines for a particular commit have the same width.
634 *
635 * This way, fields printed to the right of the graph will remain
636 * aligned for the entire commit.
c12172d2 637 */
0724cb86 638 int extra;
427fc5b8 639 if (chars_written >= graph->width)
c12172d2
AS
640 return;
641
427fc5b8 642 extra = graph->width - chars_written;
c12172d2
AS
643 strbuf_addf(sb, "%*s", (int) extra, "");
644}
645
646static void graph_output_padding_line(struct git_graph *graph,
647 struct strbuf *sb)
648{
649 int i;
650
651 /*
652 * We could conceivable be called with a NULL commit
653 * if our caller has a bug, and invokes graph_next_line()
654 * immediately after graph_init(), without first calling
655 * graph_update(). Return without outputting anything in this
656 * case.
657 */
658 if (!graph->commit)
659 return;
660
661 /*
662 * Output a padding row, that leaves all branch lines unchanged
663 */
664 for (i = 0; i < graph->num_new_columns; i++) {
427fc5b8
AC
665 strbuf_write_column(sb, &graph->new_columns[i], '|');
666 strbuf_addch(sb, ' ');
c12172d2
AS
667 }
668
427fc5b8 669 graph_pad_horizontally(graph, sb, graph->num_new_columns * 2);
c12172d2
AS
670}
671
3ad87c80
JK
672
673int graph_width(struct git_graph *graph)
674{
675 return graph->width;
676}
677
678
c12172d2
AS
679static void graph_output_skip_line(struct git_graph *graph, struct strbuf *sb)
680{
681 /*
682 * Output an ellipsis to indicate that a portion
683 * of the graph is missing.
684 */
685 strbuf_addstr(sb, "...");
427fc5b8 686 graph_pad_horizontally(graph, sb, 3);
c12172d2 687
f1979d6b
AS
688 if (graph->num_parents >= 3 &&
689 graph->commit_index < (graph->num_columns - 1))
3395908e 690 graph_update_state(graph, GRAPH_PRE_COMMIT);
c12172d2 691 else
3395908e 692 graph_update_state(graph, GRAPH_COMMIT);
c12172d2
AS
693}
694
695static void graph_output_pre_commit_line(struct git_graph *graph,
696 struct strbuf *sb)
697{
698 int num_expansion_rows;
699 int i, seen_this;
427fc5b8 700 int chars_written;
c12172d2
AS
701
702 /*
703 * This function formats a row that increases the space around a commit
704 * with multiple parents, to make room for it. It should only be
705 * called when there are 3 or more parents.
706 *
707 * We need 2 extra rows for every parent over 2.
708 */
709 assert(graph->num_parents >= 3);
710 num_expansion_rows = (graph->num_parents - 2) * 2;
711
712 /*
713 * graph->expansion_row tracks the current expansion row we are on.
714 * It should be in the range [0, num_expansion_rows - 1]
715 */
716 assert(0 <= graph->expansion_row &&
717 graph->expansion_row < num_expansion_rows);
718
719 /*
720 * Output the row
721 */
722 seen_this = 0;
427fc5b8 723 chars_written = 0;
c12172d2
AS
724 for (i = 0; i < graph->num_columns; i++) {
725 struct column *col = &graph->columns[i];
726 if (col->commit == graph->commit) {
727 seen_this = 1;
427fc5b8 728 strbuf_write_column(sb, col, '|');
36a31fea
AC
729 strbuf_addf(sb, "%*s", graph->expansion_row, "");
730 chars_written += 1 + graph->expansion_row;
3395908e
AS
731 } else if (seen_this && (graph->expansion_row == 0)) {
732 /*
733 * This is the first line of the pre-commit output.
734 * If the previous commit was a merge commit and
735 * ended in the GRAPH_POST_MERGE state, all branch
736 * lines after graph->prev_commit_index were
737 * printed as "\" on the previous line. Continue
738 * to print them as "\" on this line. Otherwise,
739 * print the branch lines as "|".
740 */
741 if (graph->prev_state == GRAPH_POST_MERGE &&
742 graph->prev_commit_index < i)
427fc5b8 743 strbuf_write_column(sb, col, '\\');
3395908e 744 else
427fc5b8
AC
745 strbuf_write_column(sb, col, '|');
746 chars_written++;
3395908e 747 } else if (seen_this && (graph->expansion_row > 0)) {
427fc5b8
AC
748 strbuf_write_column(sb, col, '\\');
749 chars_written++;
c12172d2 750 } else {
427fc5b8
AC
751 strbuf_write_column(sb, col, '|');
752 chars_written++;
c12172d2 753 }
427fc5b8
AC
754 strbuf_addch(sb, ' ');
755 chars_written++;
c12172d2
AS
756 }
757
427fc5b8 758 graph_pad_horizontally(graph, sb, chars_written);
c12172d2
AS
759
760 /*
761 * Increment graph->expansion_row,
762 * and move to state GRAPH_COMMIT if necessary
763 */
764 graph->expansion_row++;
765 if (graph->expansion_row >= num_expansion_rows)
3395908e 766 graph_update_state(graph, GRAPH_COMMIT);
c12172d2
AS
767}
768
3c68d67b
AS
769static void graph_output_commit_char(struct git_graph *graph, struct strbuf *sb)
770{
771 /*
772 * For boundary commits, print 'o'
773 * (We should only see boundary commits when revs->boundary is set.)
774 */
775 if (graph->commit->object.flags & BOUNDARY) {
776 assert(graph->revs->boundary);
777 strbuf_addch(sb, 'o');
778 return;
779 }
780
781 /*
1df2d656 782 * get_revision_mark() handles all other cases without assert()
3c68d67b 783 */
1df2d656 784 strbuf_addstr(sb, get_revision_mark(graph->revs, graph->commit));
3c68d67b
AS
785}
786
427fc5b8
AC
787/*
788 * Draw an octopus merge and return the number of characters written.
789 */
790static int graph_draw_octopus_merge(struct git_graph *graph,
791 struct strbuf *sb)
792{
793 /*
794 * Here dashless_commits represents the number of parents
795 * which don't need to have dashes (because their edges fit
796 * neatly under the commit).
797 */
798 const int dashless_commits = 2;
799 int col_num, i;
800 int num_dashes =
801 ((graph->num_parents - dashless_commits) * 2) - 1;
802 for (i = 0; i < num_dashes; i++) {
339c17bc 803 col_num = (i / 2) + dashless_commits + graph->commit_index;
427fc5b8
AC
804 strbuf_write_column(sb, &graph->new_columns[col_num], '-');
805 }
339c17bc 806 col_num = (i / 2) + dashless_commits + graph->commit_index;
427fc5b8
AC
807 strbuf_write_column(sb, &graph->new_columns[col_num], '.');
808 return num_dashes + 1;
809}
810
064bfbde 811static void graph_output_commit_line(struct git_graph *graph, struct strbuf *sb)
c12172d2
AS
812{
813 int seen_this = 0;
427fc5b8 814 int i, chars_written;
c12172d2
AS
815
816 /*
817 * Output the row containing this commit
818 * Iterate up to and including graph->num_columns,
819 * since the current commit may not be in any of the existing
820 * columns. (This happens when the current commit doesn't have any
821 * children that we have already processed.)
822 */
823 seen_this = 0;
427fc5b8 824 chars_written = 0;
c12172d2 825 for (i = 0; i <= graph->num_columns; i++) {
427fc5b8 826 struct column *col = &graph->columns[i];
c12172d2
AS
827 struct commit *col_commit;
828 if (i == graph->num_columns) {
829 if (seen_this)
830 break;
831 col_commit = graph->commit;
832 } else {
833 col_commit = graph->columns[i].commit;
834 }
835
836 if (col_commit == graph->commit) {
837 seen_this = 1;
3c68d67b 838 graph_output_commit_char(graph, sb);
427fc5b8 839 chars_written++;
c12172d2 840
a6c1a382 841 if (graph->num_parents > 2)
427fc5b8
AC
842 chars_written += graph_draw_octopus_merge(graph,
843 sb);
3395908e 844 } else if (seen_this && (graph->num_parents > 2)) {
427fc5b8
AC
845 strbuf_write_column(sb, col, '\\');
846 chars_written++;
3395908e
AS
847 } else if (seen_this && (graph->num_parents == 2)) {
848 /*
849 * This is a 2-way merge commit.
850 * There is no GRAPH_PRE_COMMIT stage for 2-way
851 * merges, so this is the first line of output
852 * for this commit. Check to see what the previous
853 * line of output was.
854 *
855 * If it was GRAPH_POST_MERGE, the branch line
856 * coming into this commit may have been '\',
857 * and not '|' or '/'. If so, output the branch
858 * line as '\' on this line, instead of '|'. This
859 * makes the output look nicer.
860 */
861 if (graph->prev_state == GRAPH_POST_MERGE &&
862 graph->prev_commit_index < i)
427fc5b8 863 strbuf_write_column(sb, col, '\\');
3395908e 864 else
427fc5b8
AC
865 strbuf_write_column(sb, col, '|');
866 chars_written++;
c12172d2 867 } else {
427fc5b8
AC
868 strbuf_write_column(sb, col, '|');
869 chars_written++;
c12172d2 870 }
427fc5b8
AC
871 strbuf_addch(sb, ' ');
872 chars_written++;
c12172d2
AS
873 }
874
427fc5b8 875 graph_pad_horizontally(graph, sb, chars_written);
c12172d2
AS
876
877 /*
878 * Update graph->state
879 */
880 if (graph->num_parents > 1)
3395908e 881 graph_update_state(graph, GRAPH_POST_MERGE);
c12172d2 882 else if (graph_is_mapping_correct(graph))
3395908e 883 graph_update_state(graph, GRAPH_PADDING);
c12172d2 884 else
3395908e 885 graph_update_state(graph, GRAPH_COLLAPSING);
c12172d2
AS
886}
887
427fc5b8
AC
888static struct column *find_new_column_by_commit(struct git_graph *graph,
889 struct commit *commit)
890{
891 int i;
892 for (i = 0; i < graph->num_new_columns; i++) {
893 if (graph->new_columns[i].commit == commit)
894 return &graph->new_columns[i];
895 }
67da52be 896 return NULL;
427fc5b8
AC
897}
898
064bfbde 899static void graph_output_post_merge_line(struct git_graph *graph, struct strbuf *sb)
c12172d2
AS
900{
901 int seen_this = 0;
427fc5b8 902 int i, j, chars_written;
c12172d2
AS
903
904 /*
905 * Output the post-merge row
906 */
427fc5b8 907 chars_written = 0;
c12172d2 908 for (i = 0; i <= graph->num_columns; i++) {
427fc5b8 909 struct column *col = &graph->columns[i];
c12172d2
AS
910 struct commit *col_commit;
911 if (i == graph->num_columns) {
912 if (seen_this)
913 break;
914 col_commit = graph->commit;
915 } else {
427fc5b8 916 col_commit = col->commit;
c12172d2
AS
917 }
918
919 if (col_commit == graph->commit) {
427fc5b8
AC
920 /*
921 * Since the current commit is a merge find
922 * the columns for the parent commits in
923 * new_columns and use those to format the
924 * edges.
925 */
926 struct commit_list *parents = NULL;
927 struct column *par_column;
c12172d2 928 seen_this = 1;
427fc5b8
AC
929 parents = first_interesting_parent(graph);
930 assert(parents);
931 par_column = find_new_column_by_commit(graph, parents->item);
932 assert(par_column);
933
934 strbuf_write_column(sb, par_column, '|');
935 chars_written++;
936 for (j = 0; j < graph->num_parents - 1; j++) {
937 parents = next_interesting_parent(graph, parents);
938 assert(parents);
939 par_column = find_new_column_by_commit(graph, parents->item);
940 assert(par_column);
941 strbuf_write_column(sb, par_column, '\\');
942 strbuf_addch(sb, ' ');
943 }
944 chars_written += j * 2;
3395908e 945 } else if (seen_this) {
427fc5b8
AC
946 strbuf_write_column(sb, col, '\\');
947 strbuf_addch(sb, ' ');
948 chars_written += 2;
c12172d2 949 } else {
427fc5b8
AC
950 strbuf_write_column(sb, col, '|');
951 strbuf_addch(sb, ' ');
952 chars_written += 2;
c12172d2
AS
953 }
954 }
955
427fc5b8 956 graph_pad_horizontally(graph, sb, chars_written);
c12172d2
AS
957
958 /*
959 * Update graph->state
960 */
961 if (graph_is_mapping_correct(graph))
3395908e 962 graph_update_state(graph, GRAPH_PADDING);
c12172d2 963 else
3395908e 964 graph_update_state(graph, GRAPH_COLLAPSING);
c12172d2
AS
965}
966
064bfbde 967static void graph_output_collapsing_line(struct git_graph *graph, struct strbuf *sb)
c12172d2
AS
968{
969 int i;
970 int *tmp_mapping;
eaf158f8
AC
971 short used_horizontal = 0;
972 int horizontal_edge = -1;
973 int horizontal_edge_target = -1;
c12172d2
AS
974
975 /*
976 * Clear out the new_mapping array
977 */
978 for (i = 0; i < graph->mapping_size; i++)
979 graph->new_mapping[i] = -1;
980
981 for (i = 0; i < graph->mapping_size; i++) {
982 int target = graph->mapping[i];
983 if (target < 0)
984 continue;
985
986 /*
987 * Since update_columns() always inserts the leftmost
988 * column first, each branch's target location should
989 * always be either its current location or to the left of
990 * its current location.
991 *
992 * We never have to move branches to the right. This makes
993 * the graph much more legible, since whenever branches
994 * cross, only one is moving directions.
995 */
996 assert(target * 2 <= i);
997
998 if (target * 2 == i) {
999 /*
1000 * This column is already in the
1001 * correct place
1002 */
1003 assert(graph->new_mapping[i] == -1);
1004 graph->new_mapping[i] = target;
1005 } else if (graph->new_mapping[i - 1] < 0) {
1006 /*
1007 * Nothing is to the left.
1008 * Move to the left by one
1009 */
1010 graph->new_mapping[i - 1] = target;
eaf158f8
AC
1011 /*
1012 * If there isn't already an edge moving horizontally
1013 * select this one.
1014 */
1015 if (horizontal_edge == -1) {
1016 int j;
1017 horizontal_edge = i;
1018 horizontal_edge_target = target;
1019 /*
1020 * The variable target is the index of the graph
1021 * column, and therefore target*2+3 is the
1022 * actual screen column of the first horizontal
1023 * line.
1024 */
1025 for (j = (target * 2)+3; j < (i - 2); j += 2)
1026 graph->new_mapping[j] = target;
1027 }
c12172d2
AS
1028 } else if (graph->new_mapping[i - 1] == target) {
1029 /*
1030 * There is a branch line to our left
1031 * already, and it is our target. We
1032 * combine with this line, since we share
1033 * the same parent commit.
1034 *
1035 * We don't have to add anything to the
1036 * output or new_mapping, since the
1037 * existing branch line has already taken
1038 * care of it.
1039 */
1040 } else {
1041 /*
1042 * There is a branch line to our left,
1043 * but it isn't our target. We need to
1044 * cross over it.
1045 *
1046 * The space just to the left of this
1047 * branch should always be empty.
eaf158f8
AC
1048 *
1049 * The branch to the left of that space
1050 * should be our eventual target.
c12172d2
AS
1051 */
1052 assert(graph->new_mapping[i - 1] > target);
1053 assert(graph->new_mapping[i - 2] < 0);
eaf158f8 1054 assert(graph->new_mapping[i - 3] == target);
c12172d2 1055 graph->new_mapping[i - 2] = target;
eaf158f8
AC
1056 /*
1057 * Mark this branch as the horizontal edge to
1058 * prevent any other edges from moving
1059 * horizontally.
1060 */
1061 if (horizontal_edge == -1)
1062 horizontal_edge = i;
c12172d2
AS
1063 }
1064 }
1065
1066 /*
1067 * The new mapping may be 1 smaller than the old mapping
1068 */
1069 if (graph->new_mapping[graph->mapping_size - 1] < 0)
1070 graph->mapping_size--;
1071
1072 /*
1073 * Output out a line based on the new mapping info
1074 */
1075 for (i = 0; i < graph->mapping_size; i++) {
1076 int target = graph->new_mapping[i];
1077 if (target < 0)
1078 strbuf_addch(sb, ' ');
1079 else if (target * 2 == i)
427fc5b8 1080 strbuf_write_column(sb, &graph->new_columns[target], '|');
eaf158f8
AC
1081 else if (target == horizontal_edge_target &&
1082 i != horizontal_edge - 1) {
1083 /*
1084 * Set the mappings for all but the
1085 * first segment to -1 so that they
1086 * won't continue into the next line.
1087 */
1088 if (i != (target * 2)+3)
1089 graph->new_mapping[i] = -1;
1090 used_horizontal = 1;
1091 strbuf_write_column(sb, &graph->new_columns[target], '_');
1092 } else {
1093 if (used_horizontal && i < horizontal_edge)
1094 graph->new_mapping[i] = -1;
427fc5b8 1095 strbuf_write_column(sb, &graph->new_columns[target], '/');
eaf158f8
AC
1096
1097 }
c12172d2
AS
1098 }
1099
427fc5b8 1100 graph_pad_horizontally(graph, sb, graph->mapping_size);
c12172d2
AS
1101
1102 /*
1103 * Swap mapping and new_mapping
1104 */
1105 tmp_mapping = graph->mapping;
1106 graph->mapping = graph->new_mapping;
1107 graph->new_mapping = tmp_mapping;
1108
1109 /*
1110 * If graph->mapping indicates that all of the branch lines
1111 * are already in the correct positions, we are done.
1112 * Otherwise, we need to collapse some branch lines together.
1113 */
1114 if (graph_is_mapping_correct(graph))
3395908e 1115 graph_update_state(graph, GRAPH_PADDING);
c12172d2
AS
1116}
1117
ac751a0b 1118int graph_next_line(struct git_graph *graph, struct strbuf *sb)
c12172d2
AS
1119{
1120 switch (graph->state) {
1121 case GRAPH_PADDING:
1122 graph_output_padding_line(graph, sb);
1123 return 0;
1124 case GRAPH_SKIP:
1125 graph_output_skip_line(graph, sb);
1126 return 0;
1127 case GRAPH_PRE_COMMIT:
1128 graph_output_pre_commit_line(graph, sb);
1129 return 0;
1130 case GRAPH_COMMIT:
1131 graph_output_commit_line(graph, sb);
1132 return 1;
1133 case GRAPH_POST_MERGE:
1134 graph_output_post_merge_line(graph, sb);
1135 return 0;
1136 case GRAPH_COLLAPSING:
1137 graph_output_collapsing_line(graph, sb);
1138 return 0;
1139 }
1140
1141 assert(0);
1142 return 0;
1143}
1144
064bfbde 1145static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
c12172d2 1146{
415792ed 1147 int i;
c12172d2
AS
1148
1149 if (graph->state != GRAPH_COMMIT) {
1150 graph_next_line(graph, sb);
1151 return;
1152 }
1153
1154 /*
1155 * Output the row containing this commit
1156 * Iterate up to and including graph->num_columns,
1157 * since the current commit may not be in any of the existing
1158 * columns. (This happens when the current commit doesn't have any
1159 * children that we have already processed.)
1160 */
1161 for (i = 0; i < graph->num_columns; i++) {
427fc5b8 1162 struct column *col = &graph->columns[i];
0176e7a7
RS
1163 strbuf_write_column(sb, col, '|');
1164 if (col->commit == graph->commit && graph->num_parents > 2)
1165 strbuf_addchars(sb, ' ', (graph->num_parents - 2) * 2);
1166 else
427fc5b8 1167 strbuf_addch(sb, ' ');
c12172d2
AS
1168 }
1169
427fc5b8 1170 graph_pad_horizontally(graph, sb, graph->num_columns);
3395908e
AS
1171
1172 /*
1173 * Update graph->prev_state since we have output a padding line
1174 */
1175 graph->prev_state = GRAPH_PADDING;
c12172d2
AS
1176}
1177
1178int graph_is_commit_finished(struct git_graph const *graph)
1179{
1180 return (graph->state == GRAPH_PADDING);
1181}
1182
1183void graph_show_commit(struct git_graph *graph)
1184{
f285a2d7 1185 struct strbuf msgbuf = STRBUF_INIT;
c12172d2
AS
1186 int shown_commit_line = 0;
1187
1188 if (!graph)
1189 return;
1190
a48ec241
JK
1191 /*
1192 * When showing a diff of a merge against each of its parents, we
1193 * are called once for each parent without graph_update having been
1194 * called. In this case, simply output a single padding line.
1195 */
1196 if (graph_is_commit_finished(graph)) {
1197 graph_show_padding(graph);
1198 shown_commit_line = 1;
1199 }
1200
656197ad 1201 while (!shown_commit_line && !graph_is_commit_finished(graph)) {
c12172d2 1202 shown_commit_line = graph_next_line(graph, &msgbuf);
c61008fd
JS
1203 fwrite(msgbuf.buf, sizeof(char), msgbuf.len,
1204 graph->revs->diffopt.file);
c12172d2 1205 if (!shown_commit_line)
c61008fd 1206 putc('\n', graph->revs->diffopt.file);
c12172d2
AS
1207 strbuf_setlen(&msgbuf, 0);
1208 }
1209
1210 strbuf_release(&msgbuf);
1211}
1212
1213void graph_show_oneline(struct git_graph *graph)
1214{
f285a2d7 1215 struct strbuf msgbuf = STRBUF_INIT;
c12172d2
AS
1216
1217 if (!graph)
1218 return;
1219
c12172d2 1220 graph_next_line(graph, &msgbuf);
c61008fd 1221 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, graph->revs->diffopt.file);
c12172d2
AS
1222 strbuf_release(&msgbuf);
1223}
1224
1225void graph_show_padding(struct git_graph *graph)
1226{
f285a2d7 1227 struct strbuf msgbuf = STRBUF_INIT;
c12172d2
AS
1228
1229 if (!graph)
1230 return;
1231
c12172d2 1232 graph_padding_line(graph, &msgbuf);
c61008fd 1233 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, graph->revs->diffopt.file);
c12172d2
AS
1234 strbuf_release(&msgbuf);
1235}
1236
1237int graph_show_remainder(struct git_graph *graph)
1238{
f285a2d7 1239 struct strbuf msgbuf = STRBUF_INIT;
c12172d2
AS
1240 int shown = 0;
1241
1242 if (!graph)
1243 return 0;
1244
1245 if (graph_is_commit_finished(graph))
1246 return 0;
1247
c12172d2
AS
1248 for (;;) {
1249 graph_next_line(graph, &msgbuf);
c61008fd
JS
1250 fwrite(msgbuf.buf, sizeof(char), msgbuf.len,
1251 graph->revs->diffopt.file);
c12172d2
AS
1252 strbuf_setlen(&msgbuf, 0);
1253 shown = 1;
1254
1255 if (!graph_is_commit_finished(graph))
c61008fd 1256 putc('\n', graph->revs->diffopt.file);
c12172d2
AS
1257 else
1258 break;
1259 }
1260 strbuf_release(&msgbuf);
1261
1262 return shown;
1263}
1264
1265
064bfbde 1266static void graph_show_strbuf(struct git_graph *graph, struct strbuf const *sb)
c12172d2
AS
1267{
1268 char *p;
1269
1270 if (!graph) {
c61008fd
JS
1271 fwrite(sb->buf, sizeof(char), sb->len,
1272 graph->revs->diffopt.file);
c12172d2
AS
1273 return;
1274 }
1275
1276 /*
1277 * Print the strbuf line by line,
1278 * and display the graph info before each line but the first.
1279 */
1280 p = sb->buf;
1281 while (p) {
1282 size_t len;
1283 char *next_p = strchr(p, '\n');
1284 if (next_p) {
1285 next_p++;
1286 len = next_p - p;
1287 } else {
1288 len = (sb->buf + sb->len) - p;
1289 }
c61008fd 1290 fwrite(p, sizeof(char), len, graph->revs->diffopt.file);
c12172d2
AS
1291 if (next_p && *next_p != '\0')
1292 graph_show_oneline(graph);
1293 p = next_p;
1294 }
1295}
1296
1297void graph_show_commit_msg(struct git_graph *graph,
1298 struct strbuf const *sb)
1299{
1300 int newline_terminated;
1301
1302 if (!graph) {
1303 /*
1304 * If there's no graph, just print the message buffer.
1305 *
1306 * The message buffer for CMIT_FMT_ONELINE and
1307 * CMIT_FMT_USERFORMAT are already missing a terminating
1308 * newline. All of the other formats should have it.
1309 */
c61008fd
JS
1310 fwrite(sb->buf, sizeof(char), sb->len,
1311 graph->revs->diffopt.file);
c12172d2
AS
1312 return;
1313 }
1314
1315 newline_terminated = (sb->len && sb->buf[sb->len - 1] == '\n');
1316
1317 /*
1318 * Show the commit message
1319 */
1320 graph_show_strbuf(graph, sb);
1321
1322 /*
1323 * If there is more output needed for this commit, show it now
1324 */
1325 if (!graph_is_commit_finished(graph)) {
1326 /*
1327 * If sb doesn't have a terminating newline, print one now,
1328 * so we can start the remainder of the graph output on a
1329 * new line.
1330 */
1331 if (!newline_terminated)
c61008fd 1332 putc('\n', graph->revs->diffopt.file);
c12172d2
AS
1333
1334 graph_show_remainder(graph);
1335
1336 /*
1337 * If sb ends with a newline, our output should too.
1338 */
1339 if (newline_terminated)
c61008fd 1340 putc('\n', graph->revs->diffopt.file);
c12172d2
AS
1341 }
1342}