doc: describe git svn init --ignore-refs
[git/git-svn.git] / graph.c
blob8b9049dd2c725f58314042deebfb69030e4321d3
1 #include "cache.h"
2 #include "commit.h"
3 #include "color.h"
4 #include "graph.h"
5 #include "revision.h"
6 #include "argv-array.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. If the graph is non-NULL, all lines but the first will be
21 * 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 * Note that unlike some other graph display functions, you must pass the file
33 * handle directly. It is assumed that this is the same file handle as the
34 * file specified by the graph diff options. This is necessary so that
35 * graph_show_strbuf can be called even with a NULL graph.
37 static void graph_show_strbuf(struct git_graph *graph,
38 FILE *file,
39 struct strbuf const *sb);
42 * TODO:
43 * - Limit the number of columns, similar to the way gitk does.
44 * If we reach more than a specified number of columns, omit
45 * sections of some columns.
48 struct column {
50 * The parent commit of this column.
52 struct commit *commit;
54 * The color to (optionally) print this column in. This is an
55 * index into column_colors.
57 unsigned short color;
60 enum graph_state {
61 GRAPH_PADDING,
62 GRAPH_SKIP,
63 GRAPH_PRE_COMMIT,
64 GRAPH_COMMIT,
65 GRAPH_POST_MERGE,
66 GRAPH_COLLAPSING
69 static void graph_show_line_prefix(const struct diff_options *diffopt)
71 if (!diffopt || !diffopt->line_prefix)
72 return;
74 fwrite(diffopt->line_prefix,
75 sizeof(char),
76 diffopt->line_prefix_length,
77 diffopt->file);
80 static const char **column_colors;
81 static unsigned short column_colors_max;
83 static void parse_graph_colors_config(struct argv_array *colors, const char *string)
85 const char *end, *start;
87 start = string;
88 end = string + strlen(string);
89 while (start < end) {
90 const char *comma = strchrnul(start, ',');
91 char color[COLOR_MAXLEN];
93 if (!color_parse_mem(start, comma - start, color))
94 argv_array_push(colors, color);
95 else
96 warning(_("ignore invalid color '%.*s' in log.graphColors"),
97 (int)(comma - start), start);
98 start = comma + 1;
100 argv_array_push(colors, GIT_COLOR_RESET);
103 void graph_set_column_colors(const char **colors, unsigned short colors_max)
105 column_colors = colors;
106 column_colors_max = colors_max;
109 static const char *column_get_color_code(unsigned short color)
111 return column_colors[color];
114 static void strbuf_write_column(struct strbuf *sb, const struct column *c,
115 char col_char)
117 if (c->color < column_colors_max)
118 strbuf_addstr(sb, column_get_color_code(c->color));
119 strbuf_addch(sb, col_char);
120 if (c->color < column_colors_max)
121 strbuf_addstr(sb, column_get_color_code(column_colors_max));
124 struct git_graph {
126 * The commit currently being processed
128 struct commit *commit;
129 /* The rev-info used for the current traversal */
130 struct rev_info *revs;
132 * The number of interesting parents that this commit has.
134 * Note that this is not the same as the actual number of parents.
135 * This count excludes parents that won't be printed in the graph
136 * output, as determined by graph_is_interesting().
138 int num_parents;
140 * The width of the graph output for this commit.
141 * All rows for this commit are padded to this width, so that
142 * messages printed after the graph output are aligned.
144 int width;
146 * The next expansion row to print
147 * when state is GRAPH_PRE_COMMIT
149 int expansion_row;
151 * The current output state.
152 * This tells us what kind of line graph_next_line() should output.
154 enum graph_state state;
156 * The output state for the previous line of output.
157 * This is primarily used to determine how the first merge line
158 * should appear, based on the last line of the previous commit.
160 enum graph_state prev_state;
162 * The index of the column that refers to this commit.
164 * If none of the incoming columns refer to this commit,
165 * this will be equal to num_columns.
167 int commit_index;
169 * The commit_index for the previously displayed commit.
171 * This is used to determine how the first line of a merge
172 * graph output should appear, based on the last line of the
173 * previous commit.
175 int prev_commit_index;
177 * The maximum number of columns that can be stored in the columns
178 * and new_columns arrays. This is also half the number of entries
179 * that can be stored in the mapping and new_mapping arrays.
181 int column_capacity;
183 * The number of columns (also called "branch lines" in some places)
185 int num_columns;
187 * The number of columns in the new_columns array
189 int num_new_columns;
191 * The number of entries in the mapping array
193 int mapping_size;
195 * The column state before we output the current commit.
197 struct column *columns;
199 * The new column state after we output the current commit.
200 * Only valid when state is GRAPH_COLLAPSING.
202 struct column *new_columns;
204 * An array that tracks the current state of each
205 * character in the output line during state GRAPH_COLLAPSING.
206 * Each entry is -1 if this character is empty, or a non-negative
207 * integer if the character contains a branch line. The value of
208 * the integer indicates the target position for this branch line.
209 * (I.e., this array maps the current column positions to their
210 * desired positions.)
212 * The maximum capacity of this array is always
213 * sizeof(int) * 2 * column_capacity.
215 int *mapping;
217 * A temporary array for computing the next mapping state
218 * while we are outputting a mapping line. This is stored as part
219 * of the git_graph simply so we don't have to allocate a new
220 * temporary array each time we have to output a collapsing line.
222 int *new_mapping;
224 * The current default column color being used. This is
225 * stored as an index into the array column_colors.
227 unsigned short default_column_color;
230 static struct strbuf *diff_output_prefix_callback(struct diff_options *opt, void *data)
232 struct git_graph *graph = data;
233 static struct strbuf msgbuf = STRBUF_INIT;
235 assert(opt);
237 strbuf_reset(&msgbuf);
238 if (opt->line_prefix)
239 strbuf_add(&msgbuf, opt->line_prefix,
240 opt->line_prefix_length);
241 if (graph)
242 graph_padding_line(graph, &msgbuf);
243 return &msgbuf;
246 static const struct diff_options *default_diffopt;
248 void graph_setup_line_prefix(struct diff_options *diffopt)
250 default_diffopt = diffopt;
252 /* setup an output prefix callback if necessary */
253 if (diffopt && !diffopt->output_prefix)
254 diffopt->output_prefix = diff_output_prefix_callback;
258 struct git_graph *graph_init(struct rev_info *opt)
260 struct git_graph *graph = xmalloc(sizeof(struct git_graph));
262 if (!column_colors) {
263 char *string;
264 if (git_config_get_string("log.graphcolors", &string)) {
265 /* not configured -- use default */
266 graph_set_column_colors(column_colors_ansi,
267 column_colors_ansi_max);
268 } else {
269 static struct argv_array custom_colors = ARGV_ARRAY_INIT;
270 argv_array_clear(&custom_colors);
271 parse_graph_colors_config(&custom_colors, string);
272 free(string);
273 /* graph_set_column_colors takes a max-index, not a count */
274 graph_set_column_colors(custom_colors.argv,
275 custom_colors.argc - 1);
279 graph->commit = NULL;
280 graph->revs = opt;
281 graph->num_parents = 0;
282 graph->expansion_row = 0;
283 graph->state = GRAPH_PADDING;
284 graph->prev_state = GRAPH_PADDING;
285 graph->commit_index = 0;
286 graph->prev_commit_index = 0;
287 graph->num_columns = 0;
288 graph->num_new_columns = 0;
289 graph->mapping_size = 0;
291 * Start the column color at the maximum value, since we'll
292 * always increment it for the first commit we output.
293 * This way we start at 0 for the first commit.
295 graph->default_column_color = column_colors_max - 1;
298 * Allocate a reasonably large default number of columns
299 * We'll automatically grow columns later if we need more room.
301 graph->column_capacity = 30;
302 ALLOC_ARRAY(graph->columns, graph->column_capacity);
303 ALLOC_ARRAY(graph->new_columns, graph->column_capacity);
304 ALLOC_ARRAY(graph->mapping, 2 * graph->column_capacity);
305 ALLOC_ARRAY(graph->new_mapping, 2 * graph->column_capacity);
308 * The diff output prefix callback, with this we can make
309 * all the diff output to align with the graph lines.
311 opt->diffopt.output_prefix = diff_output_prefix_callback;
312 opt->diffopt.output_prefix_data = graph;
314 return graph;
317 static void graph_update_state(struct git_graph *graph, enum graph_state s)
319 graph->prev_state = graph->state;
320 graph->state = s;
323 static void graph_ensure_capacity(struct git_graph *graph, int num_columns)
325 if (graph->column_capacity >= num_columns)
326 return;
328 do {
329 graph->column_capacity *= 2;
330 } while (graph->column_capacity < num_columns);
332 REALLOC_ARRAY(graph->columns, graph->column_capacity);
333 REALLOC_ARRAY(graph->new_columns, graph->column_capacity);
334 REALLOC_ARRAY(graph->mapping, graph->column_capacity * 2);
335 REALLOC_ARRAY(graph->new_mapping, graph->column_capacity * 2);
339 * Returns 1 if the commit will be printed in the graph output,
340 * and 0 otherwise.
342 static int graph_is_interesting(struct git_graph *graph, struct commit *commit)
345 * If revs->boundary is set, commits whose children have
346 * been shown are always interesting, even if they have the
347 * UNINTERESTING or TREESAME flags set.
349 if (graph->revs && graph->revs->boundary) {
350 if (commit->object.flags & CHILD_SHOWN)
351 return 1;
355 * Otherwise, use get_commit_action() to see if this commit is
356 * interesting
358 return get_commit_action(graph->revs, commit) == commit_show;
361 static struct commit_list *next_interesting_parent(struct git_graph *graph,
362 struct commit_list *orig)
364 struct commit_list *list;
367 * If revs->first_parent_only is set, only the first
368 * parent is interesting. None of the others are.
370 if (graph->revs->first_parent_only)
371 return NULL;
374 * Return the next interesting commit after orig
376 for (list = orig->next; list; list = list->next) {
377 if (graph_is_interesting(graph, list->item))
378 return list;
381 return NULL;
384 static struct commit_list *first_interesting_parent(struct git_graph *graph)
386 struct commit_list *parents = graph->commit->parents;
389 * If this commit has no parents, ignore it
391 if (!parents)
392 return NULL;
395 * If the first parent is interesting, return it
397 if (graph_is_interesting(graph, parents->item))
398 return parents;
401 * Otherwise, call next_interesting_parent() to get
402 * the next interesting parent
404 return next_interesting_parent(graph, parents);
407 static unsigned short graph_get_current_column_color(const struct git_graph *graph)
409 if (!want_color(graph->revs->diffopt.use_color))
410 return column_colors_max;
411 return graph->default_column_color;
415 * Update the graph's default column color.
417 static void graph_increment_column_color(struct git_graph *graph)
419 graph->default_column_color = (graph->default_column_color + 1) %
420 column_colors_max;
423 static unsigned short graph_find_commit_color(const struct git_graph *graph,
424 const struct commit *commit)
426 int i;
427 for (i = 0; i < graph->num_columns; i++) {
428 if (graph->columns[i].commit == commit)
429 return graph->columns[i].color;
431 return graph_get_current_column_color(graph);
434 static void graph_insert_into_new_columns(struct git_graph *graph,
435 struct commit *commit,
436 int *mapping_index)
438 int i;
441 * If the commit is already in the new_columns list, we don't need to
442 * add it. Just update the mapping correctly.
444 for (i = 0; i < graph->num_new_columns; i++) {
445 if (graph->new_columns[i].commit == commit) {
446 graph->mapping[*mapping_index] = i;
447 *mapping_index += 2;
448 return;
453 * This commit isn't already in new_columns. Add it.
455 graph->new_columns[graph->num_new_columns].commit = commit;
456 graph->new_columns[graph->num_new_columns].color = graph_find_commit_color(graph, commit);
457 graph->mapping[*mapping_index] = graph->num_new_columns;
458 *mapping_index += 2;
459 graph->num_new_columns++;
462 static void graph_update_width(struct git_graph *graph,
463 int is_commit_in_existing_columns)
466 * Compute the width needed to display the graph for this commit.
467 * This is the maximum width needed for any row. All other rows
468 * will be padded to this width.
470 * Compute the number of columns in the widest row:
471 * Count each existing column (graph->num_columns), and each new
472 * column added by this commit.
474 int max_cols = graph->num_columns + graph->num_parents;
477 * Even if the current commit has no parents to be printed, it
478 * still takes up a column for itself.
480 if (graph->num_parents < 1)
481 max_cols++;
484 * We added a column for the current commit as part of
485 * graph->num_parents. If the current commit was already in
486 * graph->columns, then we have double counted it.
488 if (is_commit_in_existing_columns)
489 max_cols--;
492 * Each column takes up 2 spaces
494 graph->width = max_cols * 2;
497 static void graph_update_columns(struct git_graph *graph)
499 struct commit_list *parent;
500 int max_new_columns;
501 int mapping_idx;
502 int i, seen_this, is_commit_in_columns;
505 * Swap graph->columns with graph->new_columns
506 * graph->columns contains the state for the previous commit,
507 * and new_columns now contains the state for our commit.
509 * We'll re-use the old columns array as storage to compute the new
510 * columns list for the commit after this one.
512 SWAP(graph->columns, graph->new_columns);
513 graph->num_columns = graph->num_new_columns;
514 graph->num_new_columns = 0;
517 * Now update new_columns and mapping with the information for the
518 * commit after this one.
520 * First, make sure we have enough room. At most, there will
521 * be graph->num_columns + graph->num_parents columns for the next
522 * commit.
524 max_new_columns = graph->num_columns + graph->num_parents;
525 graph_ensure_capacity(graph, max_new_columns);
528 * Clear out graph->mapping
530 graph->mapping_size = 2 * max_new_columns;
531 for (i = 0; i < graph->mapping_size; i++)
532 graph->mapping[i] = -1;
535 * Populate graph->new_columns and graph->mapping
537 * Some of the parents of this commit may already be in
538 * graph->columns. If so, graph->new_columns should only contain a
539 * single entry for each such commit. graph->mapping should
540 * contain information about where each current branch line is
541 * supposed to end up after the collapsing is performed.
543 seen_this = 0;
544 mapping_idx = 0;
545 is_commit_in_columns = 1;
546 for (i = 0; i <= graph->num_columns; i++) {
547 struct commit *col_commit;
548 if (i == graph->num_columns) {
549 if (seen_this)
550 break;
551 is_commit_in_columns = 0;
552 col_commit = graph->commit;
553 } else {
554 col_commit = graph->columns[i].commit;
557 if (col_commit == graph->commit) {
558 int old_mapping_idx = mapping_idx;
559 seen_this = 1;
560 graph->commit_index = i;
561 for (parent = first_interesting_parent(graph);
562 parent;
563 parent = next_interesting_parent(graph, parent)) {
565 * If this is a merge, or the start of a new
566 * childless column, increment the current
567 * color.
569 if (graph->num_parents > 1 ||
570 !is_commit_in_columns) {
571 graph_increment_column_color(graph);
573 graph_insert_into_new_columns(graph,
574 parent->item,
575 &mapping_idx);
578 * We always need to increment mapping_idx by at
579 * least 2, even if it has no interesting parents.
580 * The current commit always takes up at least 2
581 * spaces.
583 if (mapping_idx == old_mapping_idx)
584 mapping_idx += 2;
585 } else {
586 graph_insert_into_new_columns(graph, col_commit,
587 &mapping_idx);
592 * Shrink mapping_size to be the minimum necessary
594 while (graph->mapping_size > 1 &&
595 graph->mapping[graph->mapping_size - 1] < 0)
596 graph->mapping_size--;
599 * Compute graph->width for this commit
601 graph_update_width(graph, is_commit_in_columns);
604 void graph_update(struct git_graph *graph, struct commit *commit)
606 struct commit_list *parent;
609 * Set the new commit
611 graph->commit = commit;
614 * Count how many interesting parents this commit has
616 graph->num_parents = 0;
617 for (parent = first_interesting_parent(graph);
618 parent;
619 parent = next_interesting_parent(graph, parent))
621 graph->num_parents++;
625 * Store the old commit_index in prev_commit_index.
626 * graph_update_columns() will update graph->commit_index for this
627 * commit.
629 graph->prev_commit_index = graph->commit_index;
632 * Call graph_update_columns() to update
633 * columns, new_columns, and mapping.
635 graph_update_columns(graph);
637 graph->expansion_row = 0;
640 * Update graph->state.
641 * Note that we don't call graph_update_state() here, since
642 * we don't want to update graph->prev_state. No line for
643 * graph->state was ever printed.
645 * If the previous commit didn't get to the GRAPH_PADDING state,
646 * it never finished its output. Goto GRAPH_SKIP, to print out
647 * a line to indicate that portion of the graph is missing.
649 * If there are 3 or more parents, we may need to print extra rows
650 * before the commit, to expand the branch lines around it and make
651 * room for it. We need to do this only if there is a branch row
652 * (or more) to the right of this commit.
654 * If there are less than 3 parents, we can immediately print the
655 * commit line.
657 if (graph->state != GRAPH_PADDING)
658 graph->state = GRAPH_SKIP;
659 else if (graph->num_parents >= 3 &&
660 graph->commit_index < (graph->num_columns - 1))
661 graph->state = GRAPH_PRE_COMMIT;
662 else
663 graph->state = GRAPH_COMMIT;
666 static int graph_is_mapping_correct(struct git_graph *graph)
668 int i;
671 * The mapping is up to date if each entry is at its target,
672 * or is 1 greater than its target.
673 * (If it is 1 greater than the target, '/' will be printed, so it
674 * will look correct on the next row.)
676 for (i = 0; i < graph->mapping_size; i++) {
677 int target = graph->mapping[i];
678 if (target < 0)
679 continue;
680 if (target == (i / 2))
681 continue;
682 return 0;
685 return 1;
688 static void graph_pad_horizontally(struct git_graph *graph, struct strbuf *sb,
689 int chars_written)
692 * Add additional spaces to the end of the strbuf, so that all
693 * lines for a particular commit have the same width.
695 * This way, fields printed to the right of the graph will remain
696 * aligned for the entire commit.
698 int extra;
699 if (chars_written >= graph->width)
700 return;
702 extra = graph->width - chars_written;
703 strbuf_addf(sb, "%*s", (int) extra, "");
706 static void graph_output_padding_line(struct git_graph *graph,
707 struct strbuf *sb)
709 int i;
712 * We could conceivable be called with a NULL commit
713 * if our caller has a bug, and invokes graph_next_line()
714 * immediately after graph_init(), without first calling
715 * graph_update(). Return without outputting anything in this
716 * case.
718 if (!graph->commit)
719 return;
722 * Output a padding row, that leaves all branch lines unchanged
724 for (i = 0; i < graph->num_new_columns; i++) {
725 strbuf_write_column(sb, &graph->new_columns[i], '|');
726 strbuf_addch(sb, ' ');
729 graph_pad_horizontally(graph, sb, graph->num_new_columns * 2);
733 int graph_width(struct git_graph *graph)
735 return graph->width;
739 static void graph_output_skip_line(struct git_graph *graph, struct strbuf *sb)
742 * Output an ellipsis to indicate that a portion
743 * of the graph is missing.
745 strbuf_addstr(sb, "...");
746 graph_pad_horizontally(graph, sb, 3);
748 if (graph->num_parents >= 3 &&
749 graph->commit_index < (graph->num_columns - 1))
750 graph_update_state(graph, GRAPH_PRE_COMMIT);
751 else
752 graph_update_state(graph, GRAPH_COMMIT);
755 static void graph_output_pre_commit_line(struct git_graph *graph,
756 struct strbuf *sb)
758 int num_expansion_rows;
759 int i, seen_this;
760 int chars_written;
763 * This function formats a row that increases the space around a commit
764 * with multiple parents, to make room for it. It should only be
765 * called when there are 3 or more parents.
767 * We need 2 extra rows for every parent over 2.
769 assert(graph->num_parents >= 3);
770 num_expansion_rows = (graph->num_parents - 2) * 2;
773 * graph->expansion_row tracks the current expansion row we are on.
774 * It should be in the range [0, num_expansion_rows - 1]
776 assert(0 <= graph->expansion_row &&
777 graph->expansion_row < num_expansion_rows);
780 * Output the row
782 seen_this = 0;
783 chars_written = 0;
784 for (i = 0; i < graph->num_columns; i++) {
785 struct column *col = &graph->columns[i];
786 if (col->commit == graph->commit) {
787 seen_this = 1;
788 strbuf_write_column(sb, col, '|');
789 strbuf_addf(sb, "%*s", graph->expansion_row, "");
790 chars_written += 1 + graph->expansion_row;
791 } else if (seen_this && (graph->expansion_row == 0)) {
793 * This is the first line of the pre-commit output.
794 * If the previous commit was a merge commit and
795 * ended in the GRAPH_POST_MERGE state, all branch
796 * lines after graph->prev_commit_index were
797 * printed as "\" on the previous line. Continue
798 * to print them as "\" on this line. Otherwise,
799 * print the branch lines as "|".
801 if (graph->prev_state == GRAPH_POST_MERGE &&
802 graph->prev_commit_index < i)
803 strbuf_write_column(sb, col, '\\');
804 else
805 strbuf_write_column(sb, col, '|');
806 chars_written++;
807 } else if (seen_this && (graph->expansion_row > 0)) {
808 strbuf_write_column(sb, col, '\\');
809 chars_written++;
810 } else {
811 strbuf_write_column(sb, col, '|');
812 chars_written++;
814 strbuf_addch(sb, ' ');
815 chars_written++;
818 graph_pad_horizontally(graph, sb, chars_written);
821 * Increment graph->expansion_row,
822 * and move to state GRAPH_COMMIT if necessary
824 graph->expansion_row++;
825 if (graph->expansion_row >= num_expansion_rows)
826 graph_update_state(graph, GRAPH_COMMIT);
829 static void graph_output_commit_char(struct git_graph *graph, struct strbuf *sb)
832 * For boundary commits, print 'o'
833 * (We should only see boundary commits when revs->boundary is set.)
835 if (graph->commit->object.flags & BOUNDARY) {
836 assert(graph->revs->boundary);
837 strbuf_addch(sb, 'o');
838 return;
842 * get_revision_mark() handles all other cases without assert()
844 strbuf_addstr(sb, get_revision_mark(graph->revs, graph->commit));
848 * Draw an octopus merge and return the number of characters written.
850 static int graph_draw_octopus_merge(struct git_graph *graph,
851 struct strbuf *sb)
854 * Here dashless_commits represents the number of parents
855 * which don't need to have dashes (because their edges fit
856 * neatly under the commit).
858 const int dashless_commits = 2;
859 int col_num, i;
860 int num_dashes =
861 ((graph->num_parents - dashless_commits) * 2) - 1;
862 for (i = 0; i < num_dashes; i++) {
863 col_num = (i / 2) + dashless_commits + graph->commit_index;
864 strbuf_write_column(sb, &graph->new_columns[col_num], '-');
866 col_num = (i / 2) + dashless_commits + graph->commit_index;
867 strbuf_write_column(sb, &graph->new_columns[col_num], '.');
868 return num_dashes + 1;
871 static void graph_output_commit_line(struct git_graph *graph, struct strbuf *sb)
873 int seen_this = 0;
874 int i, chars_written;
877 * Output the row containing this commit
878 * Iterate up to and including graph->num_columns,
879 * since the current commit may not be in any of the existing
880 * columns. (This happens when the current commit doesn't have any
881 * children that we have already processed.)
883 seen_this = 0;
884 chars_written = 0;
885 for (i = 0; i <= graph->num_columns; i++) {
886 struct column *col = &graph->columns[i];
887 struct commit *col_commit;
888 if (i == graph->num_columns) {
889 if (seen_this)
890 break;
891 col_commit = graph->commit;
892 } else {
893 col_commit = graph->columns[i].commit;
896 if (col_commit == graph->commit) {
897 seen_this = 1;
898 graph_output_commit_char(graph, sb);
899 chars_written++;
901 if (graph->num_parents > 2)
902 chars_written += graph_draw_octopus_merge(graph,
903 sb);
904 } else if (seen_this && (graph->num_parents > 2)) {
905 strbuf_write_column(sb, col, '\\');
906 chars_written++;
907 } else if (seen_this && (graph->num_parents == 2)) {
909 * This is a 2-way merge commit.
910 * There is no GRAPH_PRE_COMMIT stage for 2-way
911 * merges, so this is the first line of output
912 * for this commit. Check to see what the previous
913 * line of output was.
915 * If it was GRAPH_POST_MERGE, the branch line
916 * coming into this commit may have been '\',
917 * and not '|' or '/'. If so, output the branch
918 * line as '\' on this line, instead of '|'. This
919 * makes the output look nicer.
921 if (graph->prev_state == GRAPH_POST_MERGE &&
922 graph->prev_commit_index < i)
923 strbuf_write_column(sb, col, '\\');
924 else
925 strbuf_write_column(sb, col, '|');
926 chars_written++;
927 } else {
928 strbuf_write_column(sb, col, '|');
929 chars_written++;
931 strbuf_addch(sb, ' ');
932 chars_written++;
935 graph_pad_horizontally(graph, sb, chars_written);
938 * Update graph->state
940 if (graph->num_parents > 1)
941 graph_update_state(graph, GRAPH_POST_MERGE);
942 else if (graph_is_mapping_correct(graph))
943 graph_update_state(graph, GRAPH_PADDING);
944 else
945 graph_update_state(graph, GRAPH_COLLAPSING);
948 static struct column *find_new_column_by_commit(struct git_graph *graph,
949 struct commit *commit)
951 int i;
952 for (i = 0; i < graph->num_new_columns; i++) {
953 if (graph->new_columns[i].commit == commit)
954 return &graph->new_columns[i];
956 return NULL;
959 static void graph_output_post_merge_line(struct git_graph *graph, struct strbuf *sb)
961 int seen_this = 0;
962 int i, j, chars_written;
965 * Output the post-merge row
967 chars_written = 0;
968 for (i = 0; i <= graph->num_columns; i++) {
969 struct column *col = &graph->columns[i];
970 struct commit *col_commit;
971 if (i == graph->num_columns) {
972 if (seen_this)
973 break;
974 col_commit = graph->commit;
975 } else {
976 col_commit = col->commit;
979 if (col_commit == graph->commit) {
981 * Since the current commit is a merge find
982 * the columns for the parent commits in
983 * new_columns and use those to format the
984 * edges.
986 struct commit_list *parents = NULL;
987 struct column *par_column;
988 seen_this = 1;
989 parents = first_interesting_parent(graph);
990 assert(parents);
991 par_column = find_new_column_by_commit(graph, parents->item);
992 assert(par_column);
994 strbuf_write_column(sb, par_column, '|');
995 chars_written++;
996 for (j = 0; j < graph->num_parents - 1; j++) {
997 parents = next_interesting_parent(graph, parents);
998 assert(parents);
999 par_column = find_new_column_by_commit(graph, parents->item);
1000 assert(par_column);
1001 strbuf_write_column(sb, par_column, '\\');
1002 strbuf_addch(sb, ' ');
1004 chars_written += j * 2;
1005 } else if (seen_this) {
1006 strbuf_write_column(sb, col, '\\');
1007 strbuf_addch(sb, ' ');
1008 chars_written += 2;
1009 } else {
1010 strbuf_write_column(sb, col, '|');
1011 strbuf_addch(sb, ' ');
1012 chars_written += 2;
1016 graph_pad_horizontally(graph, sb, chars_written);
1019 * Update graph->state
1021 if (graph_is_mapping_correct(graph))
1022 graph_update_state(graph, GRAPH_PADDING);
1023 else
1024 graph_update_state(graph, GRAPH_COLLAPSING);
1027 static void graph_output_collapsing_line(struct git_graph *graph, struct strbuf *sb)
1029 int i;
1030 short used_horizontal = 0;
1031 int horizontal_edge = -1;
1032 int horizontal_edge_target = -1;
1035 * Clear out the new_mapping array
1037 for (i = 0; i < graph->mapping_size; i++)
1038 graph->new_mapping[i] = -1;
1040 for (i = 0; i < graph->mapping_size; i++) {
1041 int target = graph->mapping[i];
1042 if (target < 0)
1043 continue;
1046 * Since update_columns() always inserts the leftmost
1047 * column first, each branch's target location should
1048 * always be either its current location or to the left of
1049 * its current location.
1051 * We never have to move branches to the right. This makes
1052 * the graph much more legible, since whenever branches
1053 * cross, only one is moving directions.
1055 assert(target * 2 <= i);
1057 if (target * 2 == i) {
1059 * This column is already in the
1060 * correct place
1062 assert(graph->new_mapping[i] == -1);
1063 graph->new_mapping[i] = target;
1064 } else if (graph->new_mapping[i - 1] < 0) {
1066 * Nothing is to the left.
1067 * Move to the left by one
1069 graph->new_mapping[i - 1] = target;
1071 * If there isn't already an edge moving horizontally
1072 * select this one.
1074 if (horizontal_edge == -1) {
1075 int j;
1076 horizontal_edge = i;
1077 horizontal_edge_target = target;
1079 * The variable target is the index of the graph
1080 * column, and therefore target*2+3 is the
1081 * actual screen column of the first horizontal
1082 * line.
1084 for (j = (target * 2)+3; j < (i - 2); j += 2)
1085 graph->new_mapping[j] = target;
1087 } else if (graph->new_mapping[i - 1] == target) {
1089 * There is a branch line to our left
1090 * already, and it is our target. We
1091 * combine with this line, since we share
1092 * the same parent commit.
1094 * We don't have to add anything to the
1095 * output or new_mapping, since the
1096 * existing branch line has already taken
1097 * care of it.
1099 } else {
1101 * There is a branch line to our left,
1102 * but it isn't our target. We need to
1103 * cross over it.
1105 * The space just to the left of this
1106 * branch should always be empty.
1108 * The branch to the left of that space
1109 * should be our eventual target.
1111 assert(graph->new_mapping[i - 1] > target);
1112 assert(graph->new_mapping[i - 2] < 0);
1113 assert(graph->new_mapping[i - 3] == target);
1114 graph->new_mapping[i - 2] = target;
1116 * Mark this branch as the horizontal edge to
1117 * prevent any other edges from moving
1118 * horizontally.
1120 if (horizontal_edge == -1)
1121 horizontal_edge = i;
1126 * The new mapping may be 1 smaller than the old mapping
1128 if (graph->new_mapping[graph->mapping_size - 1] < 0)
1129 graph->mapping_size--;
1132 * Output out a line based on the new mapping info
1134 for (i = 0; i < graph->mapping_size; i++) {
1135 int target = graph->new_mapping[i];
1136 if (target < 0)
1137 strbuf_addch(sb, ' ');
1138 else if (target * 2 == i)
1139 strbuf_write_column(sb, &graph->new_columns[target], '|');
1140 else if (target == horizontal_edge_target &&
1141 i != horizontal_edge - 1) {
1143 * Set the mappings for all but the
1144 * first segment to -1 so that they
1145 * won't continue into the next line.
1147 if (i != (target * 2)+3)
1148 graph->new_mapping[i] = -1;
1149 used_horizontal = 1;
1150 strbuf_write_column(sb, &graph->new_columns[target], '_');
1151 } else {
1152 if (used_horizontal && i < horizontal_edge)
1153 graph->new_mapping[i] = -1;
1154 strbuf_write_column(sb, &graph->new_columns[target], '/');
1159 graph_pad_horizontally(graph, sb, graph->mapping_size);
1162 * Swap mapping and new_mapping
1164 SWAP(graph->mapping, graph->new_mapping);
1167 * If graph->mapping indicates that all of the branch lines
1168 * are already in the correct positions, we are done.
1169 * Otherwise, we need to collapse some branch lines together.
1171 if (graph_is_mapping_correct(graph))
1172 graph_update_state(graph, GRAPH_PADDING);
1175 int graph_next_line(struct git_graph *graph, struct strbuf *sb)
1177 switch (graph->state) {
1178 case GRAPH_PADDING:
1179 graph_output_padding_line(graph, sb);
1180 return 0;
1181 case GRAPH_SKIP:
1182 graph_output_skip_line(graph, sb);
1183 return 0;
1184 case GRAPH_PRE_COMMIT:
1185 graph_output_pre_commit_line(graph, sb);
1186 return 0;
1187 case GRAPH_COMMIT:
1188 graph_output_commit_line(graph, sb);
1189 return 1;
1190 case GRAPH_POST_MERGE:
1191 graph_output_post_merge_line(graph, sb);
1192 return 0;
1193 case GRAPH_COLLAPSING:
1194 graph_output_collapsing_line(graph, sb);
1195 return 0;
1198 assert(0);
1199 return 0;
1202 static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
1204 int i;
1205 int chars_written = 0;
1207 if (graph->state != GRAPH_COMMIT) {
1208 graph_next_line(graph, sb);
1209 return;
1213 * Output the row containing this commit
1214 * Iterate up to and including graph->num_columns,
1215 * since the current commit may not be in any of the existing
1216 * columns. (This happens when the current commit doesn't have any
1217 * children that we have already processed.)
1219 for (i = 0; i < graph->num_columns; i++) {
1220 struct column *col = &graph->columns[i];
1222 strbuf_write_column(sb, col, '|');
1223 chars_written++;
1225 if (col->commit == graph->commit && graph->num_parents > 2) {
1226 int len = (graph->num_parents - 2) * 2;
1227 strbuf_addchars(sb, ' ', len);
1228 chars_written += len;
1229 } else {
1230 strbuf_addch(sb, ' ');
1231 chars_written++;
1235 graph_pad_horizontally(graph, sb, chars_written);
1238 * Update graph->prev_state since we have output a padding line
1240 graph->prev_state = GRAPH_PADDING;
1243 int graph_is_commit_finished(struct git_graph const *graph)
1245 return (graph->state == GRAPH_PADDING);
1248 void graph_show_commit(struct git_graph *graph)
1250 struct strbuf msgbuf = STRBUF_INIT;
1251 int shown_commit_line = 0;
1253 graph_show_line_prefix(default_diffopt);
1255 if (!graph)
1256 return;
1259 * When showing a diff of a merge against each of its parents, we
1260 * are called once for each parent without graph_update having been
1261 * called. In this case, simply output a single padding line.
1263 if (graph_is_commit_finished(graph)) {
1264 graph_show_padding(graph);
1265 shown_commit_line = 1;
1268 while (!shown_commit_line && !graph_is_commit_finished(graph)) {
1269 shown_commit_line = graph_next_line(graph, &msgbuf);
1270 fwrite(msgbuf.buf, sizeof(char), msgbuf.len,
1271 graph->revs->diffopt.file);
1272 if (!shown_commit_line) {
1273 putc('\n', graph->revs->diffopt.file);
1274 graph_show_line_prefix(&graph->revs->diffopt);
1276 strbuf_setlen(&msgbuf, 0);
1279 strbuf_release(&msgbuf);
1282 void graph_show_oneline(struct git_graph *graph)
1284 struct strbuf msgbuf = STRBUF_INIT;
1286 graph_show_line_prefix(default_diffopt);
1288 if (!graph)
1289 return;
1291 graph_next_line(graph, &msgbuf);
1292 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, graph->revs->diffopt.file);
1293 strbuf_release(&msgbuf);
1296 void graph_show_padding(struct git_graph *graph)
1298 struct strbuf msgbuf = STRBUF_INIT;
1300 graph_show_line_prefix(default_diffopt);
1302 if (!graph)
1303 return;
1305 graph_padding_line(graph, &msgbuf);
1306 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, graph->revs->diffopt.file);
1307 strbuf_release(&msgbuf);
1310 int graph_show_remainder(struct git_graph *graph)
1312 struct strbuf msgbuf = STRBUF_INIT;
1313 int shown = 0;
1315 graph_show_line_prefix(default_diffopt);
1317 if (!graph)
1318 return 0;
1320 if (graph_is_commit_finished(graph))
1321 return 0;
1323 for (;;) {
1324 graph_next_line(graph, &msgbuf);
1325 fwrite(msgbuf.buf, sizeof(char), msgbuf.len,
1326 graph->revs->diffopt.file);
1327 strbuf_setlen(&msgbuf, 0);
1328 shown = 1;
1330 if (!graph_is_commit_finished(graph)) {
1331 putc('\n', graph->revs->diffopt.file);
1332 graph_show_line_prefix(&graph->revs->diffopt);
1333 } else {
1334 break;
1337 strbuf_release(&msgbuf);
1339 return shown;
1342 static void graph_show_strbuf(struct git_graph *graph,
1343 FILE *file,
1344 struct strbuf const *sb)
1346 char *p;
1349 * Print the strbuf line by line,
1350 * and display the graph info before each line but the first.
1352 p = sb->buf;
1353 while (p) {
1354 size_t len;
1355 char *next_p = strchr(p, '\n');
1356 if (next_p) {
1357 next_p++;
1358 len = next_p - p;
1359 } else {
1360 len = (sb->buf + sb->len) - p;
1362 fwrite(p, sizeof(char), len, file);
1363 if (next_p && *next_p != '\0')
1364 graph_show_oneline(graph);
1365 p = next_p;
1369 void graph_show_commit_msg(struct git_graph *graph,
1370 FILE *file,
1371 struct strbuf const *sb)
1373 int newline_terminated;
1376 * Show the commit message
1378 graph_show_strbuf(graph, file, sb);
1380 if (!graph)
1381 return;
1383 newline_terminated = (sb->len && sb->buf[sb->len - 1] == '\n');
1386 * If there is more output needed for this commit, show it now
1388 if (!graph_is_commit_finished(graph)) {
1390 * If sb doesn't have a terminating newline, print one now,
1391 * so we can start the remainder of the graph output on a
1392 * new line.
1394 if (!newline_terminated)
1395 putc('\n', file);
1397 graph_show_remainder(graph);
1400 * If sb ends with a newline, our output should too.
1402 if (newline_terminated)
1403 putc('\n', file);