git-svn: Use GIT_SSH setting if SVN_SSH is not set
[git/git.git] / graph.c
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1#include "cache.h"
2#include "commit.h"
427fc5b8 3#include "color.h"
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4#include "graph.h"
5#include "diff.h"
6#include "revision.h"
7
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8/* Internal API */
9
10/*
11 * Output the next line for a graph.
12 * This formats the next graph line into the specified strbuf. It is not
13 * terminated with a newline.
14 *
15 * Returns 1 if the line includes the current commit, and 0 otherwise.
16 * graph_next_line() will return 1 exactly once for each time
17 * graph_update() is called.
18 */
19static int graph_next_line(struct git_graph *graph, struct strbuf *sb);
20
21/*
22 * Output a padding line in the graph.
23 * This is similar to graph_next_line(). However, it is guaranteed to
24 * never print the current commit line. Instead, if the commit line is
25 * next, it will simply output a line of vertical padding, extending the
26 * branch lines downwards, but leaving them otherwise unchanged.
27 */
28static void graph_padding_line(struct git_graph *graph, struct strbuf *sb);
29
30/*
31 * Print a strbuf to stdout. If the graph is non-NULL, all lines but the
32 * first will be prefixed with the graph output.
33 *
34 * If the strbuf ends with a newline, the output will end after this
35 * newline. A new graph line will not be printed after the final newline.
36 * If the strbuf is empty, no output will be printed.
37 *
3ea3c215 38 * Since the first line will not include the graph output, the caller is
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39 * responsible for printing this line's graph (perhaps via
40 * graph_show_commit() or graph_show_oneline()) before calling
41 * graph_show_strbuf().
42 */
43static void graph_show_strbuf(struct git_graph *graph, struct strbuf const *sb);
44
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45/*
46 * TODO:
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47 * - Limit the number of columns, similar to the way gitk does.
48 * If we reach more than a specified number of columns, omit
49 * sections of some columns.
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50 */
51
52struct column {
53 /*
54 * The parent commit of this column.
55 */
56 struct commit *commit;
57 /*
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58 * The color to (optionally) print this column in. This is an
59 * index into column_colors.
c12172d2 60 */
427fc5b8 61 unsigned short color;
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62};
63
64enum graph_state {
65 GRAPH_PADDING,
66 GRAPH_SKIP,
67 GRAPH_PRE_COMMIT,
68 GRAPH_COMMIT,
69 GRAPH_POST_MERGE,
70 GRAPH_COLLAPSING
71};
72
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73/*
74 * The list of available column colors.
75 */
76static char column_colors[][COLOR_MAXLEN] = {
77 GIT_COLOR_RED,
78 GIT_COLOR_GREEN,
79 GIT_COLOR_YELLOW,
80 GIT_COLOR_BLUE,
81 GIT_COLOR_MAGENTA,
82 GIT_COLOR_CYAN,
83 GIT_COLOR_BOLD GIT_COLOR_RED,
84 GIT_COLOR_BOLD GIT_COLOR_GREEN,
85 GIT_COLOR_BOLD GIT_COLOR_YELLOW,
86 GIT_COLOR_BOLD GIT_COLOR_BLUE,
87 GIT_COLOR_BOLD GIT_COLOR_MAGENTA,
88 GIT_COLOR_BOLD GIT_COLOR_CYAN,
89};
90
91#define COLUMN_COLORS_MAX (ARRAY_SIZE(column_colors))
92
93static const char *column_get_color_code(const struct column *c)
94{
95 return column_colors[c->color];
96}
97
98static void strbuf_write_column(struct strbuf *sb, const struct column *c,
99 char col_char)
100{
101 if (c->color < COLUMN_COLORS_MAX)
102 strbuf_addstr(sb, column_get_color_code(c));
103 strbuf_addch(sb, col_char);
104 if (c->color < COLUMN_COLORS_MAX)
105 strbuf_addstr(sb, GIT_COLOR_RESET);
106}
107
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108struct git_graph {
109 /*
110 * The commit currently being processed
111 */
112 struct commit *commit;
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113 /* The rev-info used for the current traversal */
114 struct rev_info *revs;
c12172d2 115 /*
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116 * The number of interesting parents that this commit has.
117 *
118 * Note that this is not the same as the actual number of parents.
119 * This count excludes parents that won't be printed in the graph
120 * output, as determined by graph_is_interesting().
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121 */
122 int num_parents;
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123 /*
124 * The width of the graph output for this commit.
125 * All rows for this commit are padded to this width, so that
126 * messages printed after the graph output are aligned.
127 */
128 int width;
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129 /*
130 * The next expansion row to print
131 * when state is GRAPH_PRE_COMMIT
132 */
133 int expansion_row;
134 /*
135 * The current output state.
136 * This tells us what kind of line graph_next_line() should output.
137 */
138 enum graph_state state;
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139 /*
140 * The output state for the previous line of output.
141 * This is primarily used to determine how the first merge line
142 * should appear, based on the last line of the previous commit.
143 */
144 enum graph_state prev_state;
145 /*
146 * The index of the column that refers to this commit.
147 *
148 * If none of the incoming columns refer to this commit,
149 * this will be equal to num_columns.
150 */
151 int commit_index;
152 /*
153 * The commit_index for the previously displayed commit.
154 *
155 * This is used to determine how the first line of a merge
156 * graph output should appear, based on the last line of the
157 * previous commit.
158 */
159 int prev_commit_index;
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160 /*
161 * The maximum number of columns that can be stored in the columns
162 * and new_columns arrays. This is also half the number of entries
163 * that can be stored in the mapping and new_mapping arrays.
164 */
165 int column_capacity;
166 /*
167 * The number of columns (also called "branch lines" in some places)
168 */
169 int num_columns;
170 /*
171 * The number of columns in the new_columns array
172 */
173 int num_new_columns;
174 /*
175 * The number of entries in the mapping array
176 */
177 int mapping_size;
178 /*
179 * The column state before we output the current commit.
180 */
181 struct column *columns;
182 /*
183 * The new column state after we output the current commit.
184 * Only valid when state is GRAPH_COLLAPSING.
185 */
186 struct column *new_columns;
187 /*
188 * An array that tracks the current state of each
189 * character in the output line during state GRAPH_COLLAPSING.
190 * Each entry is -1 if this character is empty, or a non-negative
191 * integer if the character contains a branch line. The value of
192 * the integer indicates the target position for this branch line.
193 * (I.e., this array maps the current column positions to their
194 * desired positions.)
195 *
196 * The maximum capacity of this array is always
197 * sizeof(int) * 2 * column_capacity.
198 */
199 int *mapping;
200 /*
201 * A temporary array for computing the next mapping state
202 * while we are outputting a mapping line. This is stored as part
203 * of the git_graph simply so we don't have to allocate a new
204 * temporary array each time we have to output a collapsing line.
205 */
206 int *new_mapping;
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207 /*
208 * The current default column color being used. This is
209 * stored as an index into the array column_colors.
210 */
211 unsigned short default_column_color;
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212};
213
7528f27d 214struct git_graph *graph_init(struct rev_info *opt)
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215{
216 struct git_graph *graph = xmalloc(sizeof(struct git_graph));
217 graph->commit = NULL;
7528f27d 218 graph->revs = opt;
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219 graph->num_parents = 0;
220 graph->expansion_row = 0;
221 graph->state = GRAPH_PADDING;
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222 graph->prev_state = GRAPH_PADDING;
223 graph->commit_index = 0;
224 graph->prev_commit_index = 0;
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225 graph->num_columns = 0;
226 graph->num_new_columns = 0;
227 graph->mapping_size = 0;
427fc5b8 228 graph->default_column_color = 0;
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229
230 /*
231 * Allocate a reasonably large default number of columns
232 * We'll automatically grow columns later if we need more room.
233 */
234 graph->column_capacity = 30;
235 graph->columns = xmalloc(sizeof(struct column) *
236 graph->column_capacity);
237 graph->new_columns = xmalloc(sizeof(struct column) *
238 graph->column_capacity);
239 graph->mapping = xmalloc(sizeof(int) * 2 * graph->column_capacity);
240 graph->new_mapping = xmalloc(sizeof(int) * 2 * graph->column_capacity);
241
242 return graph;
243}
244
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245static void graph_update_state(struct git_graph *graph, enum graph_state s)
246{
247 graph->prev_state = graph->state;
248 graph->state = s;
249}
250
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251static void graph_ensure_capacity(struct git_graph *graph, int num_columns)
252{
253 if (graph->column_capacity >= num_columns)
254 return;
255
256 do {
257 graph->column_capacity *= 2;
258 } while (graph->column_capacity < num_columns);
259
260 graph->columns = xrealloc(graph->columns,
261 sizeof(struct column) *
262 graph->column_capacity);
263 graph->new_columns = xrealloc(graph->new_columns,
264 sizeof(struct column) *
265 graph->column_capacity);
266 graph->mapping = xrealloc(graph->mapping,
267 sizeof(int) * 2 * graph->column_capacity);
268 graph->new_mapping = xrealloc(graph->new_mapping,
269 sizeof(int) * 2 * graph->column_capacity);
270}
271
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272/*
273 * Returns 1 if the commit will be printed in the graph output,
274 * and 0 otherwise.
275 */
3c68d67b 276static int graph_is_interesting(struct git_graph *graph, struct commit *commit)
37a75abc 277{
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278 /*
279 * If revs->boundary is set, commits whose children have
280 * been shown are always interesting, even if they have the
281 * UNINTERESTING or TREESAME flags set.
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282 */
283 if (graph->revs && graph->revs->boundary) {
4603ec0f 284 if (commit->object.flags & CHILD_SHOWN)
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285 return 1;
286 }
287
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288 /*
289 * Uninteresting and pruned commits won't be printed
290 */
291 return (commit->object.flags & (UNINTERESTING | TREESAME)) ? 0 : 1;
292}
293
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294static struct commit_list *next_interesting_parent(struct git_graph *graph,
295 struct commit_list *orig)
296{
297 struct commit_list *list;
298
299 /*
300 * If revs->first_parent_only is set, only the first
301 * parent is interesting. None of the others are.
302 */
303 if (graph->revs->first_parent_only)
304 return NULL;
305
306 /*
307 * Return the next interesting commit after orig
308 */
309 for (list = orig->next; list; list = list->next) {
310 if (graph_is_interesting(graph, list->item))
311 return list;
312 }
313
314 return NULL;
315}
316
317static struct commit_list *first_interesting_parent(struct git_graph *graph)
318{
319 struct commit_list *parents = graph->commit->parents;
320
321 /*
322 * If this commit has no parents, ignore it
323 */
324 if (!parents)
325 return NULL;
326
327 /*
328 * If the first parent is interesting, return it
329 */
330 if (graph_is_interesting(graph, parents->item))
331 return parents;
332
333 /*
334 * Otherwise, call next_interesting_parent() to get
335 * the next interesting parent
336 */
337 return next_interesting_parent(graph, parents);
338}
339
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340static unsigned short graph_get_current_column_color(const struct git_graph *graph)
341{
342 if (!DIFF_OPT_TST(&graph->revs->diffopt, COLOR_DIFF))
343 return COLUMN_COLORS_MAX;
344 return graph->default_column_color;
345}
346
347/*
348 * Update the graph's default column color.
349 */
350static void graph_increment_column_color(struct git_graph *graph)
351{
352 graph->default_column_color = (graph->default_column_color + 1) %
353 COLUMN_COLORS_MAX;
354}
355
356static unsigned short graph_find_commit_color(const struct git_graph *graph,
357 const struct commit *commit)
358{
359 int i;
360 for (i = 0; i < graph->num_columns; i++) {
361 if (graph->columns[i].commit == commit)
362 return graph->columns[i].color;
363 }
364 return graph_get_current_column_color(graph);
365}
366
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367static void graph_insert_into_new_columns(struct git_graph *graph,
368 struct commit *commit,
369 int *mapping_index)
370{
371 int i;
372
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373 /*
374 * If the commit is already in the new_columns list, we don't need to
375 * add it. Just update the mapping correctly.
376 */
377 for (i = 0; i < graph->num_new_columns; i++) {
378 if (graph->new_columns[i].commit == commit) {
379 graph->mapping[*mapping_index] = i;
380 *mapping_index += 2;
381 return;
382 }
383 }
384
385 /*
386 * This commit isn't already in new_columns. Add it.
387 */
388 graph->new_columns[graph->num_new_columns].commit = commit;
427fc5b8 389 graph->new_columns[graph->num_new_columns].color = graph_find_commit_color(graph, commit);
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390 graph->mapping[*mapping_index] = graph->num_new_columns;
391 *mapping_index += 2;
392 graph->num_new_columns++;
393}
394
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395static void graph_update_width(struct git_graph *graph,
396 int is_commit_in_existing_columns)
397{
398 /*
399 * Compute the width needed to display the graph for this commit.
400 * This is the maximum width needed for any row. All other rows
401 * will be padded to this width.
402 *
403 * Compute the number of columns in the widest row:
404 * Count each existing column (graph->num_columns), and each new
405 * column added by this commit.
406 */
407 int max_cols = graph->num_columns + graph->num_parents;
408
409 /*
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410 * Even if the current commit has no parents to be printed, it
411 * still takes up a column for itself.
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412 */
413 if (graph->num_parents < 1)
414 max_cols++;
415
416 /*
417 * We added a column for the the current commit as part of
418 * graph->num_parents. If the current commit was already in
419 * graph->columns, then we have double counted it.
420 */
421 if (is_commit_in_existing_columns)
422 max_cols--;
423
424 /*
425 * Each column takes up 2 spaces
426 */
427 graph->width = max_cols * 2;
428}
429
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430static void graph_update_columns(struct git_graph *graph)
431{
432 struct commit_list *parent;
433 struct column *tmp_columns;
434 int max_new_columns;
435 int mapping_idx;
0724cb86 436 int i, seen_this, is_commit_in_columns;
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437
438 /*
439 * Swap graph->columns with graph->new_columns
440 * graph->columns contains the state for the previous commit,
441 * and new_columns now contains the state for our commit.
442 *
443 * We'll re-use the old columns array as storage to compute the new
444 * columns list for the commit after this one.
445 */
446 tmp_columns = graph->columns;
447 graph->columns = graph->new_columns;
448 graph->num_columns = graph->num_new_columns;
449
450 graph->new_columns = tmp_columns;
451 graph->num_new_columns = 0;
452
453 /*
454 * Now update new_columns and mapping with the information for the
455 * commit after this one.
456 *
457 * First, make sure we have enough room. At most, there will
458 * be graph->num_columns + graph->num_parents columns for the next
459 * commit.
460 */
461 max_new_columns = graph->num_columns + graph->num_parents;
462 graph_ensure_capacity(graph, max_new_columns);
463
464 /*
465 * Clear out graph->mapping
466 */
467 graph->mapping_size = 2 * max_new_columns;
468 for (i = 0; i < graph->mapping_size; i++)
469 graph->mapping[i] = -1;
470
471 /*
472 * Populate graph->new_columns and graph->mapping
473 *
474 * Some of the parents of this commit may already be in
475 * graph->columns. If so, graph->new_columns should only contain a
476 * single entry for each such commit. graph->mapping should
477 * contain information about where each current branch line is
478 * supposed to end up after the collapsing is performed.
479 */
480 seen_this = 0;
481 mapping_idx = 0;
0724cb86 482 is_commit_in_columns = 1;
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483 for (i = 0; i <= graph->num_columns; i++) {
484 struct commit *col_commit;
485 if (i == graph->num_columns) {
486 if (seen_this)
487 break;
0724cb86 488 is_commit_in_columns = 0;
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489 col_commit = graph->commit;
490 } else {
491 col_commit = graph->columns[i].commit;
492 }
493
494 if (col_commit == graph->commit) {
37a75abc 495 int old_mapping_idx = mapping_idx;
c12172d2 496 seen_this = 1;
3395908e 497 graph->commit_index = i;
a0ebe573 498 for (parent = first_interesting_parent(graph);
c12172d2 499 parent;
a0ebe573 500 parent = next_interesting_parent(graph, parent)) {
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501 /*
502 * If this is a merge increment the current
503 * color.
504 */
505 if (graph->num_parents > 1)
506 graph_increment_column_color(graph);
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507 graph_insert_into_new_columns(graph,
508 parent->item,
509 &mapping_idx);
510 }
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511 /*
512 * We always need to increment mapping_idx by at
513 * least 2, even if it has no interesting parents.
514 * The current commit always takes up at least 2
515 * spaces.
516 */
517 if (mapping_idx == old_mapping_idx)
518 mapping_idx += 2;
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519 } else {
520 graph_insert_into_new_columns(graph, col_commit,
521 &mapping_idx);
522 }
523 }
524
525 /*
526 * Shrink mapping_size to be the minimum necessary
527 */
528 while (graph->mapping_size > 1 &&
529 graph->mapping[graph->mapping_size - 1] < 0)
530 graph->mapping_size--;
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531
532 /*
533 * Compute graph->width for this commit
534 */
535 graph_update_width(graph, is_commit_in_columns);
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536}
537
538void graph_update(struct git_graph *graph, struct commit *commit)
539{
540 struct commit_list *parent;
541
542 /*
543 * Set the new commit
544 */
545 graph->commit = commit;
546
547 /*
37a75abc 548 * Count how many interesting parents this commit has
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549 */
550 graph->num_parents = 0;
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551 for (parent = first_interesting_parent(graph);
552 parent;
553 parent = next_interesting_parent(graph, parent))
554 {
555 graph->num_parents++;
37a75abc 556 }
c12172d2 557
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558 /*
559 * Store the old commit_index in prev_commit_index.
560 * graph_update_columns() will update graph->commit_index for this
561 * commit.
562 */
563 graph->prev_commit_index = graph->commit_index;
564
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565 /*
566 * Call graph_update_columns() to update
567 * columns, new_columns, and mapping.
568 */
569 graph_update_columns(graph);
570
571 graph->expansion_row = 0;
572
573 /*
574 * Update graph->state.
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575 * Note that we don't call graph_update_state() here, since
576 * we don't want to update graph->prev_state. No line for
577 * graph->state was ever printed.
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578 *
579 * If the previous commit didn't get to the GRAPH_PADDING state,
580 * it never finished its output. Goto GRAPH_SKIP, to print out
581 * a line to indicate that portion of the graph is missing.
582 *
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583 * If there are 3 or more parents, we may need to print extra rows
584 * before the commit, to expand the branch lines around it and make
585 * room for it. We need to do this only if there is a branch row
586 * (or more) to the right of this commit.
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587 *
588 * If there are less than 3 parents, we can immediately print the
589 * commit line.
590 */
591 if (graph->state != GRAPH_PADDING)
592 graph->state = GRAPH_SKIP;
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593 else if (graph->num_parents >= 3 &&
594 graph->commit_index < (graph->num_columns - 1))
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595 graph->state = GRAPH_PRE_COMMIT;
596 else
597 graph->state = GRAPH_COMMIT;
598}
599
600static int graph_is_mapping_correct(struct git_graph *graph)
601{
602 int i;
603
604 /*
605 * The mapping is up to date if each entry is at its target,
606 * or is 1 greater than its target.
607 * (If it is 1 greater than the target, '/' will be printed, so it
608 * will look correct on the next row.)
609 */
610 for (i = 0; i < graph->mapping_size; i++) {
611 int target = graph->mapping[i];
612 if (target < 0)
613 continue;
614 if (target == (i / 2))
615 continue;
616 return 0;
617 }
618
619 return 1;
620}
621
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622static void graph_pad_horizontally(struct git_graph *graph, struct strbuf *sb,
623 int chars_written)
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624{
625 /*
626 * Add additional spaces to the end of the strbuf, so that all
627 * lines for a particular commit have the same width.
628 *
629 * This way, fields printed to the right of the graph will remain
630 * aligned for the entire commit.
c12172d2 631 */
0724cb86 632 int extra;
427fc5b8 633 if (chars_written >= graph->width)
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634 return;
635
427fc5b8 636 extra = graph->width - chars_written;
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637 strbuf_addf(sb, "%*s", (int) extra, "");
638}
639
640static void graph_output_padding_line(struct git_graph *graph,
641 struct strbuf *sb)
642{
643 int i;
644
645 /*
646 * We could conceivable be called with a NULL commit
647 * if our caller has a bug, and invokes graph_next_line()
648 * immediately after graph_init(), without first calling
649 * graph_update(). Return without outputting anything in this
650 * case.
651 */
652 if (!graph->commit)
653 return;
654
655 /*
656 * Output a padding row, that leaves all branch lines unchanged
657 */
658 for (i = 0; i < graph->num_new_columns; i++) {
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659 strbuf_write_column(sb, &graph->new_columns[i], '|');
660 strbuf_addch(sb, ' ');
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661 }
662
427fc5b8 663 graph_pad_horizontally(graph, sb, graph->num_new_columns * 2);
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664}
665
666static void graph_output_skip_line(struct git_graph *graph, struct strbuf *sb)
667{
668 /*
669 * Output an ellipsis to indicate that a portion
670 * of the graph is missing.
671 */
672 strbuf_addstr(sb, "...");
427fc5b8 673 graph_pad_horizontally(graph, sb, 3);
c12172d2 674
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675 if (graph->num_parents >= 3 &&
676 graph->commit_index < (graph->num_columns - 1))
3395908e 677 graph_update_state(graph, GRAPH_PRE_COMMIT);
c12172d2 678 else
3395908e 679 graph_update_state(graph, GRAPH_COMMIT);
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680}
681
682static void graph_output_pre_commit_line(struct git_graph *graph,
683 struct strbuf *sb)
684{
685 int num_expansion_rows;
686 int i, seen_this;
427fc5b8 687 int chars_written;
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688
689 /*
690 * This function formats a row that increases the space around a commit
691 * with multiple parents, to make room for it. It should only be
692 * called when there are 3 or more parents.
693 *
694 * We need 2 extra rows for every parent over 2.
695 */
696 assert(graph->num_parents >= 3);
697 num_expansion_rows = (graph->num_parents - 2) * 2;
698
699 /*
700 * graph->expansion_row tracks the current expansion row we are on.
701 * It should be in the range [0, num_expansion_rows - 1]
702 */
703 assert(0 <= graph->expansion_row &&
704 graph->expansion_row < num_expansion_rows);
705
706 /*
707 * Output the row
708 */
709 seen_this = 0;
427fc5b8 710 chars_written = 0;
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711 for (i = 0; i < graph->num_columns; i++) {
712 struct column *col = &graph->columns[i];
713 if (col->commit == graph->commit) {
714 seen_this = 1;
427fc5b8 715 strbuf_write_column(sb, col, '|');
36a31fea
AC
716 strbuf_addf(sb, "%*s", graph->expansion_row, "");
717 chars_written += 1 + graph->expansion_row;
3395908e
AS
718 } else if (seen_this && (graph->expansion_row == 0)) {
719 /*
720 * This is the first line of the pre-commit output.
721 * If the previous commit was a merge commit and
722 * ended in the GRAPH_POST_MERGE state, all branch
723 * lines after graph->prev_commit_index were
724 * printed as "\" on the previous line. Continue
725 * to print them as "\" on this line. Otherwise,
726 * print the branch lines as "|".
727 */
728 if (graph->prev_state == GRAPH_POST_MERGE &&
729 graph->prev_commit_index < i)
427fc5b8 730 strbuf_write_column(sb, col, '\\');
3395908e 731 else
427fc5b8
AC
732 strbuf_write_column(sb, col, '|');
733 chars_written++;
3395908e 734 } else if (seen_this && (graph->expansion_row > 0)) {
427fc5b8
AC
735 strbuf_write_column(sb, col, '\\');
736 chars_written++;
c12172d2 737 } else {
427fc5b8
AC
738 strbuf_write_column(sb, col, '|');
739 chars_written++;
c12172d2 740 }
427fc5b8
AC
741 strbuf_addch(sb, ' ');
742 chars_written++;
c12172d2
AS
743 }
744
427fc5b8 745 graph_pad_horizontally(graph, sb, chars_written);
c12172d2
AS
746
747 /*
748 * Increment graph->expansion_row,
749 * and move to state GRAPH_COMMIT if necessary
750 */
751 graph->expansion_row++;
752 if (graph->expansion_row >= num_expansion_rows)
3395908e 753 graph_update_state(graph, GRAPH_COMMIT);
c12172d2
AS
754}
755
3c68d67b
AS
756static void graph_output_commit_char(struct git_graph *graph, struct strbuf *sb)
757{
758 /*
759 * For boundary commits, print 'o'
760 * (We should only see boundary commits when revs->boundary is set.)
761 */
762 if (graph->commit->object.flags & BOUNDARY) {
763 assert(graph->revs->boundary);
764 strbuf_addch(sb, 'o');
765 return;
766 }
767
768 /*
769 * If revs->left_right is set, print '<' for commits that
770 * come from the left side, and '>' for commits from the right
771 * side.
772 */
773 if (graph->revs && graph->revs->left_right) {
774 if (graph->commit->object.flags & SYMMETRIC_LEFT)
775 strbuf_addch(sb, '<');
776 else
777 strbuf_addch(sb, '>');
778 return;
779 }
780
3c68d67b
AS
781 /*
782 * Print '*' in all other cases
783 */
784 strbuf_addch(sb, '*');
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++) {
803 col_num = (i / 2) + dashless_commits;
804 strbuf_write_column(sb, &graph->new_columns[col_num], '-');
805 }
806 col_num = (i / 2) + dashless_commits;
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
064bfbde 1118static int 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
AS
1146{
1147 int i, j;
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
AC
1162 struct column *col = &graph->columns[i];
1163 struct commit *col_commit = col->commit;
c12172d2 1164 if (col_commit == graph->commit) {
427fc5b8 1165 strbuf_write_column(sb, col, '|');
c12172d2
AS
1166
1167 if (graph->num_parents < 3)
1168 strbuf_addch(sb, ' ');
1169 else {
1170 int num_spaces = ((graph->num_parents - 2) * 2);
1171 for (j = 0; j < num_spaces; j++)
1172 strbuf_addch(sb, ' ');
1173 }
1174 } else {
427fc5b8
AC
1175 strbuf_write_column(sb, col, '|');
1176 strbuf_addch(sb, ' ');
c12172d2
AS
1177 }
1178 }
1179
427fc5b8 1180 graph_pad_horizontally(graph, sb, graph->num_columns);
3395908e
AS
1181
1182 /*
1183 * Update graph->prev_state since we have output a padding line
1184 */
1185 graph->prev_state = GRAPH_PADDING;
c12172d2
AS
1186}
1187
1188int graph_is_commit_finished(struct git_graph const *graph)
1189{
1190 return (graph->state == GRAPH_PADDING);
1191}
1192
1193void graph_show_commit(struct git_graph *graph)
1194{
f285a2d7 1195 struct strbuf msgbuf = STRBUF_INIT;
c12172d2
AS
1196 int shown_commit_line = 0;
1197
1198 if (!graph)
1199 return;
1200
c12172d2
AS
1201 while (!shown_commit_line) {
1202 shown_commit_line = graph_next_line(graph, &msgbuf);
1203 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1204 if (!shown_commit_line)
1205 putchar('\n');
1206 strbuf_setlen(&msgbuf, 0);
1207 }
1208
1209 strbuf_release(&msgbuf);
1210}
1211
1212void graph_show_oneline(struct git_graph *graph)
1213{
f285a2d7 1214 struct strbuf msgbuf = STRBUF_INIT;
c12172d2
AS
1215
1216 if (!graph)
1217 return;
1218
c12172d2
AS
1219 graph_next_line(graph, &msgbuf);
1220 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1221 strbuf_release(&msgbuf);
1222}
1223
1224void graph_show_padding(struct git_graph *graph)
1225{
f285a2d7 1226 struct strbuf msgbuf = STRBUF_INIT;
c12172d2
AS
1227
1228 if (!graph)
1229 return;
1230
c12172d2
AS
1231 graph_padding_line(graph, &msgbuf);
1232 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1233 strbuf_release(&msgbuf);
1234}
1235
1236int graph_show_remainder(struct git_graph *graph)
1237{
f285a2d7 1238 struct strbuf msgbuf = STRBUF_INIT;
c12172d2
AS
1239 int shown = 0;
1240
1241 if (!graph)
1242 return 0;
1243
1244 if (graph_is_commit_finished(graph))
1245 return 0;
1246
c12172d2
AS
1247 for (;;) {
1248 graph_next_line(graph, &msgbuf);
1249 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1250 strbuf_setlen(&msgbuf, 0);
1251 shown = 1;
1252
1253 if (!graph_is_commit_finished(graph))
1254 putchar('\n');
1255 else
1256 break;
1257 }
1258 strbuf_release(&msgbuf);
1259
1260 return shown;
1261}
1262
1263
064bfbde 1264static void graph_show_strbuf(struct git_graph *graph, struct strbuf const *sb)
c12172d2
AS
1265{
1266 char *p;
1267
1268 if (!graph) {
1269 fwrite(sb->buf, sizeof(char), sb->len, stdout);
1270 return;
1271 }
1272
1273 /*
1274 * Print the strbuf line by line,
1275 * and display the graph info before each line but the first.
1276 */
1277 p = sb->buf;
1278 while (p) {
1279 size_t len;
1280 char *next_p = strchr(p, '\n');
1281 if (next_p) {
1282 next_p++;
1283 len = next_p - p;
1284 } else {
1285 len = (sb->buf + sb->len) - p;
1286 }
1287 fwrite(p, sizeof(char), len, stdout);
1288 if (next_p && *next_p != '\0')
1289 graph_show_oneline(graph);
1290 p = next_p;
1291 }
1292}
1293
1294void graph_show_commit_msg(struct git_graph *graph,
1295 struct strbuf const *sb)
1296{
1297 int newline_terminated;
1298
1299 if (!graph) {
1300 /*
1301 * If there's no graph, just print the message buffer.
1302 *
1303 * The message buffer for CMIT_FMT_ONELINE and
1304 * CMIT_FMT_USERFORMAT are already missing a terminating
1305 * newline. All of the other formats should have it.
1306 */
1307 fwrite(sb->buf, sizeof(char), sb->len, stdout);
1308 return;
1309 }
1310
1311 newline_terminated = (sb->len && sb->buf[sb->len - 1] == '\n');
1312
1313 /*
1314 * Show the commit message
1315 */
1316 graph_show_strbuf(graph, sb);
1317
1318 /*
1319 * If there is more output needed for this commit, show it now
1320 */
1321 if (!graph_is_commit_finished(graph)) {
1322 /*
1323 * If sb doesn't have a terminating newline, print one now,
1324 * so we can start the remainder of the graph output on a
1325 * new line.
1326 */
1327 if (!newline_terminated)
1328 putchar('\n');
1329
1330 graph_show_remainder(graph);
1331
1332 /*
1333 * If sb ends with a newline, our output should too.
1334 */
1335 if (newline_terminated)
1336 putchar('\n');
1337 }
1338}