i18n: verify-tag: mark parseopt strings for translation
[git/jnareb-git.git] / graph.c
blob7e0a099f8329757b24770ec6788bf83a8398d76d
1 #include "cache.h"
2 #include "commit.h"
3 #include "color.h"
4 #include "graph.h"
5 #include "diff.h"
6 #include "revision.h"
8 /* Internal API */
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.
17 static void graph_padding_line(struct git_graph *graph, struct strbuf *sb);
20 * Print a strbuf to stdout. If the graph is non-NULL, all lines but the
21 * first will be prefixed with the graph output.
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.
27 * Since the first line will not include the graph output, the caller is
28 * responsible for printing this line's graph (perhaps via
29 * graph_show_commit() or graph_show_oneline()) before calling
30 * graph_show_strbuf().
32 static void graph_show_strbuf(struct git_graph *graph, struct strbuf const *sb);
35 * TODO:
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.
41 struct column {
43 * The parent commit of this column.
45 struct commit *commit;
47 * The color to (optionally) print this column in. This is an
48 * index into column_colors.
50 unsigned short color;
53 enum graph_state {
54 GRAPH_PADDING,
55 GRAPH_SKIP,
56 GRAPH_PRE_COMMIT,
57 GRAPH_COMMIT,
58 GRAPH_POST_MERGE,
59 GRAPH_COLLAPSING
62 static const char **column_colors;
63 static unsigned short column_colors_max;
65 void graph_set_column_colors(const char **colors, unsigned short colors_max)
67 column_colors = colors;
68 column_colors_max = colors_max;
71 static const char *column_get_color_code(unsigned short color)
73 return column_colors[color];
76 static void strbuf_write_column(struct strbuf *sb, const struct column *c,
77 char col_char)
79 if (c->color < column_colors_max)
80 strbuf_addstr(sb, column_get_color_code(c->color));
81 strbuf_addch(sb, col_char);
82 if (c->color < column_colors_max)
83 strbuf_addstr(sb, column_get_color_code(column_colors_max));
86 struct git_graph {
88 * The commit currently being processed
90 struct commit *commit;
91 /* The rev-info used for the current traversal */
92 struct rev_info *revs;
94 * The number of interesting parents that this commit has.
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().
100 int num_parents;
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.
106 int width;
108 * The next expansion row to print
109 * when state is GRAPH_PRE_COMMIT
111 int expansion_row;
113 * The current output state.
114 * This tells us what kind of line graph_next_line() should output.
116 enum graph_state state;
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.
122 enum graph_state prev_state;
124 * The index of the column that refers to this commit.
126 * If none of the incoming columns refer to this commit,
127 * this will be equal to num_columns.
129 int commit_index;
131 * The commit_index for the previously displayed commit.
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.
137 int prev_commit_index;
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.
143 int column_capacity;
145 * The number of columns (also called "branch lines" in some places)
147 int num_columns;
149 * The number of columns in the new_columns array
151 int num_new_columns;
153 * The number of entries in the mapping array
155 int mapping_size;
157 * The column state before we output the current commit.
159 struct column *columns;
161 * The new column state after we output the current commit.
162 * Only valid when state is GRAPH_COLLAPSING.
164 struct column *new_columns;
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.)
174 * The maximum capacity of this array is always
175 * sizeof(int) * 2 * column_capacity.
177 int *mapping;
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.
184 int *new_mapping;
186 * The current default column color being used. This is
187 * stored as an index into the array column_colors.
189 unsigned short default_column_color;
192 static struct strbuf *diff_output_prefix_callback(struct diff_options *opt, void *data)
194 struct git_graph *graph = data;
195 static struct strbuf msgbuf = STRBUF_INIT;
197 assert(opt);
198 assert(graph);
200 opt->output_prefix_length = graph->width;
201 strbuf_reset(&msgbuf);
202 graph_padding_line(graph, &msgbuf);
203 return &msgbuf;
206 struct git_graph *graph_init(struct rev_info *opt)
208 struct git_graph *graph = xmalloc(sizeof(struct git_graph));
210 if (!column_colors)
211 graph_set_column_colors(column_colors_ansi,
212 column_colors_ansi_max);
214 graph->commit = NULL;
215 graph->revs = opt;
216 graph->num_parents = 0;
217 graph->expansion_row = 0;
218 graph->state = GRAPH_PADDING;
219 graph->prev_state = GRAPH_PADDING;
220 graph->commit_index = 0;
221 graph->prev_commit_index = 0;
222 graph->num_columns = 0;
223 graph->num_new_columns = 0;
224 graph->mapping_size = 0;
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.
230 graph->default_column_color = column_colors_max - 1;
233 * Allocate a reasonably large default number of columns
234 * We'll automatically grow columns later if we need more room.
236 graph->column_capacity = 30;
237 graph->columns = xmalloc(sizeof(struct column) *
238 graph->column_capacity);
239 graph->new_columns = xmalloc(sizeof(struct column) *
240 graph->column_capacity);
241 graph->mapping = xmalloc(sizeof(int) * 2 * graph->column_capacity);
242 graph->new_mapping = xmalloc(sizeof(int) * 2 * graph->column_capacity);
245 * The diff output prefix callback, with this we can make
246 * all the diff output to align with the graph lines.
248 opt->diffopt.output_prefix = diff_output_prefix_callback;
249 opt->diffopt.output_prefix_data = graph;
250 opt->diffopt.output_prefix_length = 0;
252 return graph;
255 static void graph_update_state(struct git_graph *graph, enum graph_state s)
257 graph->prev_state = graph->state;
258 graph->state = s;
261 static void graph_ensure_capacity(struct git_graph *graph, int num_columns)
263 if (graph->column_capacity >= num_columns)
264 return;
266 do {
267 graph->column_capacity *= 2;
268 } while (graph->column_capacity < num_columns);
270 graph->columns = xrealloc(graph->columns,
271 sizeof(struct column) *
272 graph->column_capacity);
273 graph->new_columns = xrealloc(graph->new_columns,
274 sizeof(struct column) *
275 graph->column_capacity);
276 graph->mapping = xrealloc(graph->mapping,
277 sizeof(int) * 2 * graph->column_capacity);
278 graph->new_mapping = xrealloc(graph->new_mapping,
279 sizeof(int) * 2 * graph->column_capacity);
283 * Returns 1 if the commit will be printed in the graph output,
284 * and 0 otherwise.
286 static int graph_is_interesting(struct git_graph *graph, struct commit *commit)
289 * If revs->boundary is set, commits whose children have
290 * been shown are always interesting, even if they have the
291 * UNINTERESTING or TREESAME flags set.
293 if (graph->revs && graph->revs->boundary) {
294 if (commit->object.flags & CHILD_SHOWN)
295 return 1;
299 * Otherwise, use get_commit_action() to see if this commit is
300 * interesting
302 return get_commit_action(graph->revs, commit) == commit_show;
305 static struct commit_list *next_interesting_parent(struct git_graph *graph,
306 struct commit_list *orig)
308 struct commit_list *list;
311 * If revs->first_parent_only is set, only the first
312 * parent is interesting. None of the others are.
314 if (graph->revs->first_parent_only)
315 return NULL;
318 * Return the next interesting commit after orig
320 for (list = orig->next; list; list = list->next) {
321 if (graph_is_interesting(graph, list->item))
322 return list;
325 return NULL;
328 static struct commit_list *first_interesting_parent(struct git_graph *graph)
330 struct commit_list *parents = graph->commit->parents;
333 * If this commit has no parents, ignore it
335 if (!parents)
336 return NULL;
339 * If the first parent is interesting, return it
341 if (graph_is_interesting(graph, parents->item))
342 return parents;
345 * Otherwise, call next_interesting_parent() to get
346 * the next interesting parent
348 return next_interesting_parent(graph, parents);
351 static unsigned short graph_get_current_column_color(const struct git_graph *graph)
353 if (!want_color(graph->revs->diffopt.use_color))
354 return column_colors_max;
355 return graph->default_column_color;
359 * Update the graph's default column color.
361 static void graph_increment_column_color(struct git_graph *graph)
363 graph->default_column_color = (graph->default_column_color + 1) %
364 column_colors_max;
367 static unsigned short graph_find_commit_color(const struct git_graph *graph,
368 const struct commit *commit)
370 int i;
371 for (i = 0; i < graph->num_columns; i++) {
372 if (graph->columns[i].commit == commit)
373 return graph->columns[i].color;
375 return graph_get_current_column_color(graph);
378 static void graph_insert_into_new_columns(struct git_graph *graph,
379 struct commit *commit,
380 int *mapping_index)
382 int i;
385 * If the commit is already in the new_columns list, we don't need to
386 * add it. Just update the mapping correctly.
388 for (i = 0; i < graph->num_new_columns; i++) {
389 if (graph->new_columns[i].commit == commit) {
390 graph->mapping[*mapping_index] = i;
391 *mapping_index += 2;
392 return;
397 * This commit isn't already in new_columns. Add it.
399 graph->new_columns[graph->num_new_columns].commit = commit;
400 graph->new_columns[graph->num_new_columns].color = graph_find_commit_color(graph, commit);
401 graph->mapping[*mapping_index] = graph->num_new_columns;
402 *mapping_index += 2;
403 graph->num_new_columns++;
406 static void graph_update_width(struct git_graph *graph,
407 int is_commit_in_existing_columns)
410 * Compute the width needed to display the graph for this commit.
411 * This is the maximum width needed for any row. All other rows
412 * will be padded to this width.
414 * Compute the number of columns in the widest row:
415 * Count each existing column (graph->num_columns), and each new
416 * column added by this commit.
418 int max_cols = graph->num_columns + graph->num_parents;
421 * Even if the current commit has no parents to be printed, it
422 * still takes up a column for itself.
424 if (graph->num_parents < 1)
425 max_cols++;
428 * We added a column for the current commit as part of
429 * graph->num_parents. If the current commit was already in
430 * graph->columns, then we have double counted it.
432 if (is_commit_in_existing_columns)
433 max_cols--;
436 * Each column takes up 2 spaces
438 graph->width = max_cols * 2;
441 static void graph_update_columns(struct git_graph *graph)
443 struct commit_list *parent;
444 struct column *tmp_columns;
445 int max_new_columns;
446 int mapping_idx;
447 int i, seen_this, is_commit_in_columns;
450 * Swap graph->columns with graph->new_columns
451 * graph->columns contains the state for the previous commit,
452 * and new_columns now contains the state for our commit.
454 * We'll re-use the old columns array as storage to compute the new
455 * columns list for the commit after this one.
457 tmp_columns = graph->columns;
458 graph->columns = graph->new_columns;
459 graph->num_columns = graph->num_new_columns;
461 graph->new_columns = tmp_columns;
462 graph->num_new_columns = 0;
465 * Now update new_columns and mapping with the information for the
466 * commit after this one.
468 * First, make sure we have enough room. At most, there will
469 * be graph->num_columns + graph->num_parents columns for the next
470 * commit.
472 max_new_columns = graph->num_columns + graph->num_parents;
473 graph_ensure_capacity(graph, max_new_columns);
476 * Clear out graph->mapping
478 graph->mapping_size = 2 * max_new_columns;
479 for (i = 0; i < graph->mapping_size; i++)
480 graph->mapping[i] = -1;
483 * Populate graph->new_columns and graph->mapping
485 * Some of the parents of this commit may already be in
486 * graph->columns. If so, graph->new_columns should only contain a
487 * single entry for each such commit. graph->mapping should
488 * contain information about where each current branch line is
489 * supposed to end up after the collapsing is performed.
491 seen_this = 0;
492 mapping_idx = 0;
493 is_commit_in_columns = 1;
494 for (i = 0; i <= graph->num_columns; i++) {
495 struct commit *col_commit;
496 if (i == graph->num_columns) {
497 if (seen_this)
498 break;
499 is_commit_in_columns = 0;
500 col_commit = graph->commit;
501 } else {
502 col_commit = graph->columns[i].commit;
505 if (col_commit == graph->commit) {
506 int old_mapping_idx = mapping_idx;
507 seen_this = 1;
508 graph->commit_index = i;
509 for (parent = first_interesting_parent(graph);
510 parent;
511 parent = next_interesting_parent(graph, parent)) {
513 * If this is a merge, or the start of a new
514 * childless column, increment the current
515 * color.
517 if (graph->num_parents > 1 ||
518 !is_commit_in_columns) {
519 graph_increment_column_color(graph);
521 graph_insert_into_new_columns(graph,
522 parent->item,
523 &mapping_idx);
526 * We always need to increment mapping_idx by at
527 * least 2, even if it has no interesting parents.
528 * The current commit always takes up at least 2
529 * spaces.
531 if (mapping_idx == old_mapping_idx)
532 mapping_idx += 2;
533 } else {
534 graph_insert_into_new_columns(graph, col_commit,
535 &mapping_idx);
540 * Shrink mapping_size to be the minimum necessary
542 while (graph->mapping_size > 1 &&
543 graph->mapping[graph->mapping_size - 1] < 0)
544 graph->mapping_size--;
547 * Compute graph->width for this commit
549 graph_update_width(graph, is_commit_in_columns);
552 void graph_update(struct git_graph *graph, struct commit *commit)
554 struct commit_list *parent;
557 * Set the new commit
559 graph->commit = commit;
562 * Count how many interesting parents this commit has
564 graph->num_parents = 0;
565 for (parent = first_interesting_parent(graph);
566 parent;
567 parent = next_interesting_parent(graph, parent))
569 graph->num_parents++;
573 * Store the old commit_index in prev_commit_index.
574 * graph_update_columns() will update graph->commit_index for this
575 * commit.
577 graph->prev_commit_index = graph->commit_index;
580 * Call graph_update_columns() to update
581 * columns, new_columns, and mapping.
583 graph_update_columns(graph);
585 graph->expansion_row = 0;
588 * Update graph->state.
589 * Note that we don't call graph_update_state() here, since
590 * we don't want to update graph->prev_state. No line for
591 * graph->state was ever printed.
593 * If the previous commit didn't get to the GRAPH_PADDING state,
594 * it never finished its output. Goto GRAPH_SKIP, to print out
595 * a line to indicate that portion of the graph is missing.
597 * If there are 3 or more parents, we may need to print extra rows
598 * before the commit, to expand the branch lines around it and make
599 * room for it. We need to do this only if there is a branch row
600 * (or more) to the right of this commit.
602 * If there are less than 3 parents, we can immediately print the
603 * commit line.
605 if (graph->state != GRAPH_PADDING)
606 graph->state = GRAPH_SKIP;
607 else if (graph->num_parents >= 3 &&
608 graph->commit_index < (graph->num_columns - 1))
609 graph->state = GRAPH_PRE_COMMIT;
610 else
611 graph->state = GRAPH_COMMIT;
614 static int graph_is_mapping_correct(struct git_graph *graph)
616 int i;
619 * The mapping is up to date if each entry is at its target,
620 * or is 1 greater than its target.
621 * (If it is 1 greater than the target, '/' will be printed, so it
622 * will look correct on the next row.)
624 for (i = 0; i < graph->mapping_size; i++) {
625 int target = graph->mapping[i];
626 if (target < 0)
627 continue;
628 if (target == (i / 2))
629 continue;
630 return 0;
633 return 1;
636 static void graph_pad_horizontally(struct git_graph *graph, struct strbuf *sb,
637 int chars_written)
640 * Add additional spaces to the end of the strbuf, so that all
641 * lines for a particular commit have the same width.
643 * This way, fields printed to the right of the graph will remain
644 * aligned for the entire commit.
646 int extra;
647 if (chars_written >= graph->width)
648 return;
650 extra = graph->width - chars_written;
651 strbuf_addf(sb, "%*s", (int) extra, "");
654 static void graph_output_padding_line(struct git_graph *graph,
655 struct strbuf *sb)
657 int i;
660 * We could conceivable be called with a NULL commit
661 * if our caller has a bug, and invokes graph_next_line()
662 * immediately after graph_init(), without first calling
663 * graph_update(). Return without outputting anything in this
664 * case.
666 if (!graph->commit)
667 return;
670 * Output a padding row, that leaves all branch lines unchanged
672 for (i = 0; i < graph->num_new_columns; i++) {
673 strbuf_write_column(sb, &graph->new_columns[i], '|');
674 strbuf_addch(sb, ' ');
677 graph_pad_horizontally(graph, sb, graph->num_new_columns * 2);
680 static void graph_output_skip_line(struct git_graph *graph, struct strbuf *sb)
683 * Output an ellipsis to indicate that a portion
684 * of the graph is missing.
686 strbuf_addstr(sb, "...");
687 graph_pad_horizontally(graph, sb, 3);
689 if (graph->num_parents >= 3 &&
690 graph->commit_index < (graph->num_columns - 1))
691 graph_update_state(graph, GRAPH_PRE_COMMIT);
692 else
693 graph_update_state(graph, GRAPH_COMMIT);
696 static void graph_output_pre_commit_line(struct git_graph *graph,
697 struct strbuf *sb)
699 int num_expansion_rows;
700 int i, seen_this;
701 int chars_written;
704 * This function formats a row that increases the space around a commit
705 * with multiple parents, to make room for it. It should only be
706 * called when there are 3 or more parents.
708 * We need 2 extra rows for every parent over 2.
710 assert(graph->num_parents >= 3);
711 num_expansion_rows = (graph->num_parents - 2) * 2;
714 * graph->expansion_row tracks the current expansion row we are on.
715 * It should be in the range [0, num_expansion_rows - 1]
717 assert(0 <= graph->expansion_row &&
718 graph->expansion_row < num_expansion_rows);
721 * Output the row
723 seen_this = 0;
724 chars_written = 0;
725 for (i = 0; i < graph->num_columns; i++) {
726 struct column *col = &graph->columns[i];
727 if (col->commit == graph->commit) {
728 seen_this = 1;
729 strbuf_write_column(sb, col, '|');
730 strbuf_addf(sb, "%*s", graph->expansion_row, "");
731 chars_written += 1 + graph->expansion_row;
732 } else if (seen_this && (graph->expansion_row == 0)) {
734 * This is the first line of the pre-commit output.
735 * If the previous commit was a merge commit and
736 * ended in the GRAPH_POST_MERGE state, all branch
737 * lines after graph->prev_commit_index were
738 * printed as "\" on the previous line. Continue
739 * to print them as "\" on this line. Otherwise,
740 * print the branch lines as "|".
742 if (graph->prev_state == GRAPH_POST_MERGE &&
743 graph->prev_commit_index < i)
744 strbuf_write_column(sb, col, '\\');
745 else
746 strbuf_write_column(sb, col, '|');
747 chars_written++;
748 } else if (seen_this && (graph->expansion_row > 0)) {
749 strbuf_write_column(sb, col, '\\');
750 chars_written++;
751 } else {
752 strbuf_write_column(sb, col, '|');
753 chars_written++;
755 strbuf_addch(sb, ' ');
756 chars_written++;
759 graph_pad_horizontally(graph, sb, chars_written);
762 * Increment graph->expansion_row,
763 * and move to state GRAPH_COMMIT if necessary
765 graph->expansion_row++;
766 if (graph->expansion_row >= num_expansion_rows)
767 graph_update_state(graph, GRAPH_COMMIT);
770 static void graph_output_commit_char(struct git_graph *graph, struct strbuf *sb)
773 * For boundary commits, print 'o'
774 * (We should only see boundary commits when revs->boundary is set.)
776 if (graph->commit->object.flags & BOUNDARY) {
777 assert(graph->revs->boundary);
778 strbuf_addch(sb, 'o');
779 return;
783 * get_revision_mark() handles all other cases without assert()
785 strbuf_addstr(sb, get_revision_mark(graph->revs, graph->commit));
789 * Draw an octopus merge and return the number of characters written.
791 static int graph_draw_octopus_merge(struct git_graph *graph,
792 struct strbuf *sb)
795 * Here dashless_commits represents the number of parents
796 * which don't need to have dashes (because their edges fit
797 * neatly under the commit).
799 const int dashless_commits = 2;
800 int col_num, i;
801 int num_dashes =
802 ((graph->num_parents - dashless_commits) * 2) - 1;
803 for (i = 0; i < num_dashes; i++) {
804 col_num = (i / 2) + dashless_commits;
805 strbuf_write_column(sb, &graph->new_columns[col_num], '-');
807 col_num = (i / 2) + dashless_commits;
808 strbuf_write_column(sb, &graph->new_columns[col_num], '.');
809 return num_dashes + 1;
812 static void graph_output_commit_line(struct git_graph *graph, struct strbuf *sb)
814 int seen_this = 0;
815 int i, chars_written;
818 * Output the row containing this commit
819 * Iterate up to and including graph->num_columns,
820 * since the current commit may not be in any of the existing
821 * columns. (This happens when the current commit doesn't have any
822 * children that we have already processed.)
824 seen_this = 0;
825 chars_written = 0;
826 for (i = 0; i <= graph->num_columns; i++) {
827 struct column *col = &graph->columns[i];
828 struct commit *col_commit;
829 if (i == graph->num_columns) {
830 if (seen_this)
831 break;
832 col_commit = graph->commit;
833 } else {
834 col_commit = graph->columns[i].commit;
837 if (col_commit == graph->commit) {
838 seen_this = 1;
839 graph_output_commit_char(graph, sb);
840 chars_written++;
842 if (graph->num_parents > 2)
843 chars_written += graph_draw_octopus_merge(graph,
844 sb);
845 } else if (seen_this && (graph->num_parents > 2)) {
846 strbuf_write_column(sb, col, '\\');
847 chars_written++;
848 } else if (seen_this && (graph->num_parents == 2)) {
850 * This is a 2-way merge commit.
851 * There is no GRAPH_PRE_COMMIT stage for 2-way
852 * merges, so this is the first line of output
853 * for this commit. Check to see what the previous
854 * line of output was.
856 * If it was GRAPH_POST_MERGE, the branch line
857 * coming into this commit may have been '\',
858 * and not '|' or '/'. If so, output the branch
859 * line as '\' on this line, instead of '|'. This
860 * makes the output look nicer.
862 if (graph->prev_state == GRAPH_POST_MERGE &&
863 graph->prev_commit_index < i)
864 strbuf_write_column(sb, col, '\\');
865 else
866 strbuf_write_column(sb, col, '|');
867 chars_written++;
868 } else {
869 strbuf_write_column(sb, col, '|');
870 chars_written++;
872 strbuf_addch(sb, ' ');
873 chars_written++;
876 graph_pad_horizontally(graph, sb, chars_written);
879 * Update graph->state
881 if (graph->num_parents > 1)
882 graph_update_state(graph, GRAPH_POST_MERGE);
883 else if (graph_is_mapping_correct(graph))
884 graph_update_state(graph, GRAPH_PADDING);
885 else
886 graph_update_state(graph, GRAPH_COLLAPSING);
889 static struct column *find_new_column_by_commit(struct git_graph *graph,
890 struct commit *commit)
892 int i;
893 for (i = 0; i < graph->num_new_columns; i++) {
894 if (graph->new_columns[i].commit == commit)
895 return &graph->new_columns[i];
897 return NULL;
900 static void graph_output_post_merge_line(struct git_graph *graph, struct strbuf *sb)
902 int seen_this = 0;
903 int i, j, chars_written;
906 * Output the post-merge row
908 chars_written = 0;
909 for (i = 0; i <= graph->num_columns; i++) {
910 struct column *col = &graph->columns[i];
911 struct commit *col_commit;
912 if (i == graph->num_columns) {
913 if (seen_this)
914 break;
915 col_commit = graph->commit;
916 } else {
917 col_commit = col->commit;
920 if (col_commit == graph->commit) {
922 * Since the current commit is a merge find
923 * the columns for the parent commits in
924 * new_columns and use those to format the
925 * edges.
927 struct commit_list *parents = NULL;
928 struct column *par_column;
929 seen_this = 1;
930 parents = first_interesting_parent(graph);
931 assert(parents);
932 par_column = find_new_column_by_commit(graph, parents->item);
933 assert(par_column);
935 strbuf_write_column(sb, par_column, '|');
936 chars_written++;
937 for (j = 0; j < graph->num_parents - 1; j++) {
938 parents = next_interesting_parent(graph, parents);
939 assert(parents);
940 par_column = find_new_column_by_commit(graph, parents->item);
941 assert(par_column);
942 strbuf_write_column(sb, par_column, '\\');
943 strbuf_addch(sb, ' ');
945 chars_written += j * 2;
946 } else if (seen_this) {
947 strbuf_write_column(sb, col, '\\');
948 strbuf_addch(sb, ' ');
949 chars_written += 2;
950 } else {
951 strbuf_write_column(sb, col, '|');
952 strbuf_addch(sb, ' ');
953 chars_written += 2;
957 graph_pad_horizontally(graph, sb, chars_written);
960 * Update graph->state
962 if (graph_is_mapping_correct(graph))
963 graph_update_state(graph, GRAPH_PADDING);
964 else
965 graph_update_state(graph, GRAPH_COLLAPSING);
968 static void graph_output_collapsing_line(struct git_graph *graph, struct strbuf *sb)
970 int i;
971 int *tmp_mapping;
972 short used_horizontal = 0;
973 int horizontal_edge = -1;
974 int horizontal_edge_target = -1;
977 * Clear out the new_mapping array
979 for (i = 0; i < graph->mapping_size; i++)
980 graph->new_mapping[i] = -1;
982 for (i = 0; i < graph->mapping_size; i++) {
983 int target = graph->mapping[i];
984 if (target < 0)
985 continue;
988 * Since update_columns() always inserts the leftmost
989 * column first, each branch's target location should
990 * always be either its current location or to the left of
991 * its current location.
993 * We never have to move branches to the right. This makes
994 * the graph much more legible, since whenever branches
995 * cross, only one is moving directions.
997 assert(target * 2 <= i);
999 if (target * 2 == i) {
1001 * This column is already in the
1002 * correct place
1004 assert(graph->new_mapping[i] == -1);
1005 graph->new_mapping[i] = target;
1006 } else if (graph->new_mapping[i - 1] < 0) {
1008 * Nothing is to the left.
1009 * Move to the left by one
1011 graph->new_mapping[i - 1] = target;
1013 * If there isn't already an edge moving horizontally
1014 * select this one.
1016 if (horizontal_edge == -1) {
1017 int j;
1018 horizontal_edge = i;
1019 horizontal_edge_target = target;
1021 * The variable target is the index of the graph
1022 * column, and therefore target*2+3 is the
1023 * actual screen column of the first horizontal
1024 * line.
1026 for (j = (target * 2)+3; j < (i - 2); j += 2)
1027 graph->new_mapping[j] = target;
1029 } else if (graph->new_mapping[i - 1] == target) {
1031 * There is a branch line to our left
1032 * already, and it is our target. We
1033 * combine with this line, since we share
1034 * the same parent commit.
1036 * We don't have to add anything to the
1037 * output or new_mapping, since the
1038 * existing branch line has already taken
1039 * care of it.
1041 } else {
1043 * There is a branch line to our left,
1044 * but it isn't our target. We need to
1045 * cross over it.
1047 * The space just to the left of this
1048 * branch should always be empty.
1050 * The branch to the left of that space
1051 * should be our eventual target.
1053 assert(graph->new_mapping[i - 1] > target);
1054 assert(graph->new_mapping[i - 2] < 0);
1055 assert(graph->new_mapping[i - 3] == target);
1056 graph->new_mapping[i - 2] = target;
1058 * Mark this branch as the horizontal edge to
1059 * prevent any other edges from moving
1060 * horizontally.
1062 if (horizontal_edge == -1)
1063 horizontal_edge = i;
1068 * The new mapping may be 1 smaller than the old mapping
1070 if (graph->new_mapping[graph->mapping_size - 1] < 0)
1071 graph->mapping_size--;
1074 * Output out a line based on the new mapping info
1076 for (i = 0; i < graph->mapping_size; i++) {
1077 int target = graph->new_mapping[i];
1078 if (target < 0)
1079 strbuf_addch(sb, ' ');
1080 else if (target * 2 == i)
1081 strbuf_write_column(sb, &graph->new_columns[target], '|');
1082 else if (target == horizontal_edge_target &&
1083 i != horizontal_edge - 1) {
1085 * Set the mappings for all but the
1086 * first segment to -1 so that they
1087 * won't continue into the next line.
1089 if (i != (target * 2)+3)
1090 graph->new_mapping[i] = -1;
1091 used_horizontal = 1;
1092 strbuf_write_column(sb, &graph->new_columns[target], '_');
1093 } else {
1094 if (used_horizontal && i < horizontal_edge)
1095 graph->new_mapping[i] = -1;
1096 strbuf_write_column(sb, &graph->new_columns[target], '/');
1101 graph_pad_horizontally(graph, sb, graph->mapping_size);
1104 * Swap mapping and new_mapping
1106 tmp_mapping = graph->mapping;
1107 graph->mapping = graph->new_mapping;
1108 graph->new_mapping = tmp_mapping;
1111 * If graph->mapping indicates that all of the branch lines
1112 * are already in the correct positions, we are done.
1113 * Otherwise, we need to collapse some branch lines together.
1115 if (graph_is_mapping_correct(graph))
1116 graph_update_state(graph, GRAPH_PADDING);
1119 int graph_next_line(struct git_graph *graph, struct strbuf *sb)
1121 switch (graph->state) {
1122 case GRAPH_PADDING:
1123 graph_output_padding_line(graph, sb);
1124 return 0;
1125 case GRAPH_SKIP:
1126 graph_output_skip_line(graph, sb);
1127 return 0;
1128 case GRAPH_PRE_COMMIT:
1129 graph_output_pre_commit_line(graph, sb);
1130 return 0;
1131 case GRAPH_COMMIT:
1132 graph_output_commit_line(graph, sb);
1133 return 1;
1134 case GRAPH_POST_MERGE:
1135 graph_output_post_merge_line(graph, sb);
1136 return 0;
1137 case GRAPH_COLLAPSING:
1138 graph_output_collapsing_line(graph, sb);
1139 return 0;
1142 assert(0);
1143 return 0;
1146 static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
1148 int i, j;
1150 if (graph->state != GRAPH_COMMIT) {
1151 graph_next_line(graph, sb);
1152 return;
1156 * Output the row containing this commit
1157 * Iterate up to and including graph->num_columns,
1158 * since the current commit may not be in any of the existing
1159 * columns. (This happens when the current commit doesn't have any
1160 * children that we have already processed.)
1162 for (i = 0; i < graph->num_columns; i++) {
1163 struct column *col = &graph->columns[i];
1164 struct commit *col_commit = col->commit;
1165 if (col_commit == graph->commit) {
1166 strbuf_write_column(sb, col, '|');
1168 if (graph->num_parents < 3)
1169 strbuf_addch(sb, ' ');
1170 else {
1171 int num_spaces = ((graph->num_parents - 2) * 2);
1172 for (j = 0; j < num_spaces; j++)
1173 strbuf_addch(sb, ' ');
1175 } else {
1176 strbuf_write_column(sb, col, '|');
1177 strbuf_addch(sb, ' ');
1181 graph_pad_horizontally(graph, sb, graph->num_columns);
1184 * Update graph->prev_state since we have output a padding line
1186 graph->prev_state = GRAPH_PADDING;
1189 int graph_is_commit_finished(struct git_graph const *graph)
1191 return (graph->state == GRAPH_PADDING);
1194 void graph_show_commit(struct git_graph *graph)
1196 struct strbuf msgbuf = STRBUF_INIT;
1197 int shown_commit_line = 0;
1199 if (!graph)
1200 return;
1202 while (!shown_commit_line) {
1203 shown_commit_line = graph_next_line(graph, &msgbuf);
1204 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1205 if (!shown_commit_line)
1206 putchar('\n');
1207 strbuf_setlen(&msgbuf, 0);
1210 strbuf_release(&msgbuf);
1213 void graph_show_oneline(struct git_graph *graph)
1215 struct strbuf msgbuf = STRBUF_INIT;
1217 if (!graph)
1218 return;
1220 graph_next_line(graph, &msgbuf);
1221 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1222 strbuf_release(&msgbuf);
1225 void graph_show_padding(struct git_graph *graph)
1227 struct strbuf msgbuf = STRBUF_INIT;
1229 if (!graph)
1230 return;
1232 graph_padding_line(graph, &msgbuf);
1233 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1234 strbuf_release(&msgbuf);
1237 int graph_show_remainder(struct git_graph *graph)
1239 struct strbuf msgbuf = STRBUF_INIT;
1240 int shown = 0;
1242 if (!graph)
1243 return 0;
1245 if (graph_is_commit_finished(graph))
1246 return 0;
1248 for (;;) {
1249 graph_next_line(graph, &msgbuf);
1250 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1251 strbuf_setlen(&msgbuf, 0);
1252 shown = 1;
1254 if (!graph_is_commit_finished(graph))
1255 putchar('\n');
1256 else
1257 break;
1259 strbuf_release(&msgbuf);
1261 return shown;
1265 static void graph_show_strbuf(struct git_graph *graph, struct strbuf const *sb)
1267 char *p;
1269 if (!graph) {
1270 fwrite(sb->buf, sizeof(char), sb->len, stdout);
1271 return;
1275 * Print the strbuf line by line,
1276 * and display the graph info before each line but the first.
1278 p = sb->buf;
1279 while (p) {
1280 size_t len;
1281 char *next_p = strchr(p, '\n');
1282 if (next_p) {
1283 next_p++;
1284 len = next_p - p;
1285 } else {
1286 len = (sb->buf + sb->len) - p;
1288 fwrite(p, sizeof(char), len, stdout);
1289 if (next_p && *next_p != '\0')
1290 graph_show_oneline(graph);
1291 p = next_p;
1295 void graph_show_commit_msg(struct git_graph *graph,
1296 struct strbuf const *sb)
1298 int newline_terminated;
1300 if (!graph) {
1302 * If there's no graph, just print the message buffer.
1304 * The message buffer for CMIT_FMT_ONELINE and
1305 * CMIT_FMT_USERFORMAT are already missing a terminating
1306 * newline. All of the other formats should have it.
1308 fwrite(sb->buf, sizeof(char), sb->len, stdout);
1309 return;
1312 newline_terminated = (sb->len && sb->buf[sb->len - 1] == '\n');
1315 * Show the commit message
1317 graph_show_strbuf(graph, sb);
1320 * If there is more output needed for this commit, show it now
1322 if (!graph_is_commit_finished(graph)) {
1324 * If sb doesn't have a terminating newline, print one now,
1325 * so we can start the remainder of the graph output on a
1326 * new line.
1328 if (!newline_terminated)
1329 putchar('\n');
1331 graph_show_remainder(graph);
1334 * If sb ends with a newline, our output should too.
1336 if (newline_terminated)
1337 putchar('\n');