Merge branch 'maint-1.6.1' into maint
[git/kirr.git] / graph.c
blob162a516ee15cca1f8ab118dd41b803a5d76e42ff
1 #include "cache.h"
2 #include "commit.h"
3 #include "graph.h"
4 #include "diff.h"
5 #include "revision.h"
7 /* Internal API */
9 /*
10 * Output the next line for a graph.
11 * This formats the next graph line into the specified strbuf. It is not
12 * terminated with a newline.
14 * Returns 1 if the line includes the current commit, and 0 otherwise.
15 * graph_next_line() will return 1 exactly once for each time
16 * graph_update() is called.
18 static int graph_next_line(struct git_graph *graph, struct strbuf *sb);
21 * Output a padding line in the graph.
22 * This is similar to graph_next_line(). However, it is guaranteed to
23 * never print the current commit line. Instead, if the commit line is
24 * next, it will simply output a line of vertical padding, extending the
25 * branch lines downwards, but leaving them otherwise unchanged.
27 static void graph_padding_line(struct git_graph *graph, struct strbuf *sb);
30 * Print a strbuf to stdout. If the graph is non-NULL, all lines but the
31 * first will be prefixed with the graph output.
33 * If the strbuf ends with a newline, the output will end after this
34 * newline. A new graph line will not be printed after the final newline.
35 * If the strbuf is empty, no output will be printed.
37 * Since the first line will not include the graph ouput, the caller is
38 * responsible for printing this line's graph (perhaps via
39 * graph_show_commit() or graph_show_oneline()) before calling
40 * graph_show_strbuf().
42 static void graph_show_strbuf(struct git_graph *graph, struct strbuf const *sb);
45 * TODO:
46 * - Add colors to the graph.
47 * Pick a color for each column, and print all characters
48 * in that column with the specified color.
50 * - Limit the number of columns, similar to the way gitk does.
51 * If we reach more than a specified number of columns, omit
52 * sections of some columns.
54 * - The output during the GRAPH_PRE_COMMIT and GRAPH_COLLAPSING states
55 * could be made more compact by printing horizontal lines, instead of
56 * long diagonal lines. For example, during collapsing, something like
57 * this: instead of this:
58 * | | | | | | | | | |
59 * | |_|_|/ | | | |/
60 * |/| | | | | |/|
61 * | | | | | |/| |
62 * |/| | |
63 * | | | |
65 * If there are several parallel diagonal lines, they will need to be
66 * replaced with horizontal lines on subsequent rows.
69 struct column {
71 * The parent commit of this column.
73 struct commit *commit;
75 * XXX: Once we add support for colors, struct column could also
76 * contain the color of its branch line.
80 enum graph_state {
81 GRAPH_PADDING,
82 GRAPH_SKIP,
83 GRAPH_PRE_COMMIT,
84 GRAPH_COMMIT,
85 GRAPH_POST_MERGE,
86 GRAPH_COLLAPSING
89 struct git_graph {
91 * The commit currently being processed
93 struct commit *commit;
94 /* The rev-info used for the current traversal */
95 struct rev_info *revs;
97 * The number of interesting parents that this commit has.
99 * Note that this is not the same as the actual number of parents.
100 * This count excludes parents that won't be printed in the graph
101 * output, as determined by graph_is_interesting().
103 int num_parents;
105 * The width of the graph output for this commit.
106 * All rows for this commit are padded to this width, so that
107 * messages printed after the graph output are aligned.
109 int width;
111 * The next expansion row to print
112 * when state is GRAPH_PRE_COMMIT
114 int expansion_row;
116 * The current output state.
117 * This tells us what kind of line graph_next_line() should output.
119 enum graph_state state;
121 * The output state for the previous line of output.
122 * This is primarily used to determine how the first merge line
123 * should appear, based on the last line of the previous commit.
125 enum graph_state prev_state;
127 * The index of the column that refers to this commit.
129 * If none of the incoming columns refer to this commit,
130 * this will be equal to num_columns.
132 int commit_index;
134 * The commit_index for the previously displayed commit.
136 * This is used to determine how the first line of a merge
137 * graph output should appear, based on the last line of the
138 * previous commit.
140 int prev_commit_index;
142 * The maximum number of columns that can be stored in the columns
143 * and new_columns arrays. This is also half the number of entries
144 * that can be stored in the mapping and new_mapping arrays.
146 int column_capacity;
148 * The number of columns (also called "branch lines" in some places)
150 int num_columns;
152 * The number of columns in the new_columns array
154 int num_new_columns;
156 * The number of entries in the mapping array
158 int mapping_size;
160 * The column state before we output the current commit.
162 struct column *columns;
164 * The new column state after we output the current commit.
165 * Only valid when state is GRAPH_COLLAPSING.
167 struct column *new_columns;
169 * An array that tracks the current state of each
170 * character in the output line during state GRAPH_COLLAPSING.
171 * Each entry is -1 if this character is empty, or a non-negative
172 * integer if the character contains a branch line. The value of
173 * the integer indicates the target position for this branch line.
174 * (I.e., this array maps the current column positions to their
175 * desired positions.)
177 * The maximum capacity of this array is always
178 * sizeof(int) * 2 * column_capacity.
180 int *mapping;
182 * A temporary array for computing the next mapping state
183 * while we are outputting a mapping line. This is stored as part
184 * of the git_graph simply so we don't have to allocate a new
185 * temporary array each time we have to output a collapsing line.
187 int *new_mapping;
190 struct git_graph *graph_init(struct rev_info *opt)
192 struct git_graph *graph = xmalloc(sizeof(struct git_graph));
193 graph->commit = NULL;
194 graph->revs = opt;
195 graph->num_parents = 0;
196 graph->expansion_row = 0;
197 graph->state = GRAPH_PADDING;
198 graph->prev_state = GRAPH_PADDING;
199 graph->commit_index = 0;
200 graph->prev_commit_index = 0;
201 graph->num_columns = 0;
202 graph->num_new_columns = 0;
203 graph->mapping_size = 0;
206 * Allocate a reasonably large default number of columns
207 * We'll automatically grow columns later if we need more room.
209 graph->column_capacity = 30;
210 graph->columns = xmalloc(sizeof(struct column) *
211 graph->column_capacity);
212 graph->new_columns = xmalloc(sizeof(struct column) *
213 graph->column_capacity);
214 graph->mapping = xmalloc(sizeof(int) * 2 * graph->column_capacity);
215 graph->new_mapping = xmalloc(sizeof(int) * 2 * graph->column_capacity);
217 return graph;
220 static void graph_update_state(struct git_graph *graph, enum graph_state s)
222 graph->prev_state = graph->state;
223 graph->state = s;
226 static void graph_ensure_capacity(struct git_graph *graph, int num_columns)
228 if (graph->column_capacity >= num_columns)
229 return;
231 do {
232 graph->column_capacity *= 2;
233 } while (graph->column_capacity < num_columns);
235 graph->columns = xrealloc(graph->columns,
236 sizeof(struct column) *
237 graph->column_capacity);
238 graph->new_columns = xrealloc(graph->new_columns,
239 sizeof(struct column) *
240 graph->column_capacity);
241 graph->mapping = xrealloc(graph->mapping,
242 sizeof(int) * 2 * graph->column_capacity);
243 graph->new_mapping = xrealloc(graph->new_mapping,
244 sizeof(int) * 2 * graph->column_capacity);
248 * Returns 1 if the commit will be printed in the graph output,
249 * and 0 otherwise.
251 static int graph_is_interesting(struct git_graph *graph, struct commit *commit)
254 * If revs->boundary is set, commits whose children have
255 * been shown are always interesting, even if they have the
256 * UNINTERESTING or TREESAME flags set.
258 if (graph->revs && graph->revs->boundary) {
259 if (commit->object.flags & CHILD_SHOWN)
260 return 1;
264 * Uninteresting and pruned commits won't be printed
266 return (commit->object.flags & (UNINTERESTING | TREESAME)) ? 0 : 1;
269 static struct commit_list *next_interesting_parent(struct git_graph *graph,
270 struct commit_list *orig)
272 struct commit_list *list;
275 * If revs->first_parent_only is set, only the first
276 * parent is interesting. None of the others are.
278 if (graph->revs->first_parent_only)
279 return NULL;
282 * Return the next interesting commit after orig
284 for (list = orig->next; list; list = list->next) {
285 if (graph_is_interesting(graph, list->item))
286 return list;
289 return NULL;
292 static struct commit_list *first_interesting_parent(struct git_graph *graph)
294 struct commit_list *parents = graph->commit->parents;
297 * If this commit has no parents, ignore it
299 if (!parents)
300 return NULL;
303 * If the first parent is interesting, return it
305 if (graph_is_interesting(graph, parents->item))
306 return parents;
309 * Otherwise, call next_interesting_parent() to get
310 * the next interesting parent
312 return next_interesting_parent(graph, parents);
315 static void graph_insert_into_new_columns(struct git_graph *graph,
316 struct commit *commit,
317 int *mapping_index)
319 int i;
322 * If the commit is already in the new_columns list, we don't need to
323 * add it. Just update the mapping correctly.
325 for (i = 0; i < graph->num_new_columns; i++) {
326 if (graph->new_columns[i].commit == commit) {
327 graph->mapping[*mapping_index] = i;
328 *mapping_index += 2;
329 return;
334 * This commit isn't already in new_columns. Add it.
336 graph->new_columns[graph->num_new_columns].commit = commit;
337 graph->mapping[*mapping_index] = graph->num_new_columns;
338 *mapping_index += 2;
339 graph->num_new_columns++;
342 static void graph_update_width(struct git_graph *graph,
343 int is_commit_in_existing_columns)
346 * Compute the width needed to display the graph for this commit.
347 * This is the maximum width needed for any row. All other rows
348 * will be padded to this width.
350 * Compute the number of columns in the widest row:
351 * Count each existing column (graph->num_columns), and each new
352 * column added by this commit.
354 int max_cols = graph->num_columns + graph->num_parents;
357 * Even if the current commit has no parents to be printed, it
358 * still takes up a column for itself.
360 if (graph->num_parents < 1)
361 max_cols++;
364 * We added a column for the the current commit as part of
365 * graph->num_parents. If the current commit was already in
366 * graph->columns, then we have double counted it.
368 if (is_commit_in_existing_columns)
369 max_cols--;
372 * Each column takes up 2 spaces
374 graph->width = max_cols * 2;
377 static void graph_update_columns(struct git_graph *graph)
379 struct commit_list *parent;
380 struct column *tmp_columns;
381 int max_new_columns;
382 int mapping_idx;
383 int i, seen_this, is_commit_in_columns;
386 * Swap graph->columns with graph->new_columns
387 * graph->columns contains the state for the previous commit,
388 * and new_columns now contains the state for our commit.
390 * We'll re-use the old columns array as storage to compute the new
391 * columns list for the commit after this one.
393 tmp_columns = graph->columns;
394 graph->columns = graph->new_columns;
395 graph->num_columns = graph->num_new_columns;
397 graph->new_columns = tmp_columns;
398 graph->num_new_columns = 0;
401 * Now update new_columns and mapping with the information for the
402 * commit after this one.
404 * First, make sure we have enough room. At most, there will
405 * be graph->num_columns + graph->num_parents columns for the next
406 * commit.
408 max_new_columns = graph->num_columns + graph->num_parents;
409 graph_ensure_capacity(graph, max_new_columns);
412 * Clear out graph->mapping
414 graph->mapping_size = 2 * max_new_columns;
415 for (i = 0; i < graph->mapping_size; i++)
416 graph->mapping[i] = -1;
419 * Populate graph->new_columns and graph->mapping
421 * Some of the parents of this commit may already be in
422 * graph->columns. If so, graph->new_columns should only contain a
423 * single entry for each such commit. graph->mapping should
424 * contain information about where each current branch line is
425 * supposed to end up after the collapsing is performed.
427 seen_this = 0;
428 mapping_idx = 0;
429 is_commit_in_columns = 1;
430 for (i = 0; i <= graph->num_columns; i++) {
431 struct commit *col_commit;
432 if (i == graph->num_columns) {
433 if (seen_this)
434 break;
435 is_commit_in_columns = 0;
436 col_commit = graph->commit;
437 } else {
438 col_commit = graph->columns[i].commit;
441 if (col_commit == graph->commit) {
442 int old_mapping_idx = mapping_idx;
443 seen_this = 1;
444 graph->commit_index = i;
445 for (parent = first_interesting_parent(graph);
446 parent;
447 parent = next_interesting_parent(graph, parent)) {
448 graph_insert_into_new_columns(graph,
449 parent->item,
450 &mapping_idx);
453 * We always need to increment mapping_idx by at
454 * least 2, even if it has no interesting parents.
455 * The current commit always takes up at least 2
456 * spaces.
458 if (mapping_idx == old_mapping_idx)
459 mapping_idx += 2;
460 } else {
461 graph_insert_into_new_columns(graph, col_commit,
462 &mapping_idx);
467 * Shrink mapping_size to be the minimum necessary
469 while (graph->mapping_size > 1 &&
470 graph->mapping[graph->mapping_size - 1] < 0)
471 graph->mapping_size--;
474 * Compute graph->width for this commit
476 graph_update_width(graph, is_commit_in_columns);
479 void graph_update(struct git_graph *graph, struct commit *commit)
481 struct commit_list *parent;
484 * Set the new commit
486 graph->commit = commit;
489 * Count how many interesting parents this commit has
491 graph->num_parents = 0;
492 for (parent = first_interesting_parent(graph);
493 parent;
494 parent = next_interesting_parent(graph, parent))
496 graph->num_parents++;
500 * Store the old commit_index in prev_commit_index.
501 * graph_update_columns() will update graph->commit_index for this
502 * commit.
504 graph->prev_commit_index = graph->commit_index;
507 * Call graph_update_columns() to update
508 * columns, new_columns, and mapping.
510 graph_update_columns(graph);
512 graph->expansion_row = 0;
515 * Update graph->state.
516 * Note that we don't call graph_update_state() here, since
517 * we don't want to update graph->prev_state. No line for
518 * graph->state was ever printed.
520 * If the previous commit didn't get to the GRAPH_PADDING state,
521 * it never finished its output. Goto GRAPH_SKIP, to print out
522 * a line to indicate that portion of the graph is missing.
524 * If there are 3 or more parents, we may need to print extra rows
525 * before the commit, to expand the branch lines around it and make
526 * room for it. We need to do this only if there is a branch row
527 * (or more) to the right of this commit.
529 * If there are less than 3 parents, we can immediately print the
530 * commit line.
532 if (graph->state != GRAPH_PADDING)
533 graph->state = GRAPH_SKIP;
534 else if (graph->num_parents >= 3 &&
535 graph->commit_index < (graph->num_columns - 1))
536 graph->state = GRAPH_PRE_COMMIT;
537 else
538 graph->state = GRAPH_COMMIT;
541 static int graph_is_mapping_correct(struct git_graph *graph)
543 int i;
546 * The mapping is up to date if each entry is at its target,
547 * or is 1 greater than its target.
548 * (If it is 1 greater than the target, '/' will be printed, so it
549 * will look correct on the next row.)
551 for (i = 0; i < graph->mapping_size; i++) {
552 int target = graph->mapping[i];
553 if (target < 0)
554 continue;
555 if (target == (i / 2))
556 continue;
557 return 0;
560 return 1;
563 static void graph_pad_horizontally(struct git_graph *graph, struct strbuf *sb)
566 * Add additional spaces to the end of the strbuf, so that all
567 * lines for a particular commit have the same width.
569 * This way, fields printed to the right of the graph will remain
570 * aligned for the entire commit.
572 int extra;
573 if (sb->len >= graph->width)
574 return;
576 extra = graph->width - sb->len;
577 strbuf_addf(sb, "%*s", (int) extra, "");
580 static void graph_output_padding_line(struct git_graph *graph,
581 struct strbuf *sb)
583 int i;
586 * We could conceivable be called with a NULL commit
587 * if our caller has a bug, and invokes graph_next_line()
588 * immediately after graph_init(), without first calling
589 * graph_update(). Return without outputting anything in this
590 * case.
592 if (!graph->commit)
593 return;
596 * Output a padding row, that leaves all branch lines unchanged
598 for (i = 0; i < graph->num_new_columns; i++) {
599 strbuf_addstr(sb, "| ");
602 graph_pad_horizontally(graph, sb);
605 static void graph_output_skip_line(struct git_graph *graph, struct strbuf *sb)
608 * Output an ellipsis to indicate that a portion
609 * of the graph is missing.
611 strbuf_addstr(sb, "...");
612 graph_pad_horizontally(graph, sb);
614 if (graph->num_parents >= 3 &&
615 graph->commit_index < (graph->num_columns - 1))
616 graph_update_state(graph, GRAPH_PRE_COMMIT);
617 else
618 graph_update_state(graph, GRAPH_COMMIT);
621 static void graph_output_pre_commit_line(struct git_graph *graph,
622 struct strbuf *sb)
624 int num_expansion_rows;
625 int i, seen_this;
628 * This function formats a row that increases the space around a commit
629 * with multiple parents, to make room for it. It should only be
630 * called when there are 3 or more parents.
632 * We need 2 extra rows for every parent over 2.
634 assert(graph->num_parents >= 3);
635 num_expansion_rows = (graph->num_parents - 2) * 2;
638 * graph->expansion_row tracks the current expansion row we are on.
639 * It should be in the range [0, num_expansion_rows - 1]
641 assert(0 <= graph->expansion_row &&
642 graph->expansion_row < num_expansion_rows);
645 * Output the row
647 seen_this = 0;
648 for (i = 0; i < graph->num_columns; i++) {
649 struct column *col = &graph->columns[i];
650 if (col->commit == graph->commit) {
651 seen_this = 1;
652 strbuf_addf(sb, "| %*s", graph->expansion_row, "");
653 } else if (seen_this && (graph->expansion_row == 0)) {
655 * This is the first line of the pre-commit output.
656 * If the previous commit was a merge commit and
657 * ended in the GRAPH_POST_MERGE state, all branch
658 * lines after graph->prev_commit_index were
659 * printed as "\" on the previous line. Continue
660 * to print them as "\" on this line. Otherwise,
661 * print the branch lines as "|".
663 if (graph->prev_state == GRAPH_POST_MERGE &&
664 graph->prev_commit_index < i)
665 strbuf_addstr(sb, "\\ ");
666 else
667 strbuf_addstr(sb, "| ");
668 } else if (seen_this && (graph->expansion_row > 0)) {
669 strbuf_addstr(sb, "\\ ");
670 } else {
671 strbuf_addstr(sb, "| ");
675 graph_pad_horizontally(graph, sb);
678 * Increment graph->expansion_row,
679 * and move to state GRAPH_COMMIT if necessary
681 graph->expansion_row++;
682 if (graph->expansion_row >= num_expansion_rows)
683 graph_update_state(graph, GRAPH_COMMIT);
686 static void graph_output_commit_char(struct git_graph *graph, struct strbuf *sb)
689 * For boundary commits, print 'o'
690 * (We should only see boundary commits when revs->boundary is set.)
692 if (graph->commit->object.flags & BOUNDARY) {
693 assert(graph->revs->boundary);
694 strbuf_addch(sb, 'o');
695 return;
699 * If revs->left_right is set, print '<' for commits that
700 * come from the left side, and '>' for commits from the right
701 * side.
703 if (graph->revs && graph->revs->left_right) {
704 if (graph->commit->object.flags & SYMMETRIC_LEFT)
705 strbuf_addch(sb, '<');
706 else
707 strbuf_addch(sb, '>');
708 return;
712 * Print '*' in all other cases
714 strbuf_addch(sb, '*');
717 static void graph_output_commit_line(struct git_graph *graph, struct strbuf *sb)
719 int seen_this = 0;
720 int i, j;
723 * Output the row containing this commit
724 * Iterate up to and including graph->num_columns,
725 * since the current commit may not be in any of the existing
726 * columns. (This happens when the current commit doesn't have any
727 * children that we have already processed.)
729 seen_this = 0;
730 for (i = 0; i <= graph->num_columns; i++) {
731 struct commit *col_commit;
732 if (i == graph->num_columns) {
733 if (seen_this)
734 break;
735 col_commit = graph->commit;
736 } else {
737 col_commit = graph->columns[i].commit;
740 if (col_commit == graph->commit) {
741 seen_this = 1;
742 graph_output_commit_char(graph, sb);
744 if (graph->num_parents < 3)
745 strbuf_addch(sb, ' ');
746 else {
747 int num_dashes =
748 ((graph->num_parents - 2) * 2) - 1;
749 for (j = 0; j < num_dashes; j++)
750 strbuf_addch(sb, '-');
751 strbuf_addstr(sb, ". ");
753 } else if (seen_this && (graph->num_parents > 2)) {
754 strbuf_addstr(sb, "\\ ");
755 } else if (seen_this && (graph->num_parents == 2)) {
757 * This is a 2-way merge commit.
758 * There is no GRAPH_PRE_COMMIT stage for 2-way
759 * merges, so this is the first line of output
760 * for this commit. Check to see what the previous
761 * line of output was.
763 * If it was GRAPH_POST_MERGE, the branch line
764 * coming into this commit may have been '\',
765 * and not '|' or '/'. If so, output the branch
766 * line as '\' on this line, instead of '|'. This
767 * makes the output look nicer.
769 if (graph->prev_state == GRAPH_POST_MERGE &&
770 graph->prev_commit_index < i)
771 strbuf_addstr(sb, "\\ ");
772 else
773 strbuf_addstr(sb, "| ");
774 } else {
775 strbuf_addstr(sb, "| ");
779 graph_pad_horizontally(graph, sb);
782 * Update graph->state
784 if (graph->num_parents > 1)
785 graph_update_state(graph, GRAPH_POST_MERGE);
786 else if (graph_is_mapping_correct(graph))
787 graph_update_state(graph, GRAPH_PADDING);
788 else
789 graph_update_state(graph, GRAPH_COLLAPSING);
792 static void graph_output_post_merge_line(struct git_graph *graph, struct strbuf *sb)
794 int seen_this = 0;
795 int i, j;
798 * Output the post-merge row
800 for (i = 0; i <= graph->num_columns; i++) {
801 struct commit *col_commit;
802 if (i == graph->num_columns) {
803 if (seen_this)
804 break;
805 col_commit = graph->commit;
806 } else {
807 col_commit = graph->columns[i].commit;
810 if (col_commit == graph->commit) {
811 seen_this = 1;
812 strbuf_addch(sb, '|');
813 for (j = 0; j < graph->num_parents - 1; j++)
814 strbuf_addstr(sb, "\\ ");
815 } else if (seen_this) {
816 strbuf_addstr(sb, "\\ ");
817 } else {
818 strbuf_addstr(sb, "| ");
822 graph_pad_horizontally(graph, sb);
825 * Update graph->state
827 if (graph_is_mapping_correct(graph))
828 graph_update_state(graph, GRAPH_PADDING);
829 else
830 graph_update_state(graph, GRAPH_COLLAPSING);
833 static void graph_output_collapsing_line(struct git_graph *graph, struct strbuf *sb)
835 int i;
836 int *tmp_mapping;
839 * Clear out the new_mapping array
841 for (i = 0; i < graph->mapping_size; i++)
842 graph->new_mapping[i] = -1;
844 for (i = 0; i < graph->mapping_size; i++) {
845 int target = graph->mapping[i];
846 if (target < 0)
847 continue;
850 * Since update_columns() always inserts the leftmost
851 * column first, each branch's target location should
852 * always be either its current location or to the left of
853 * its current location.
855 * We never have to move branches to the right. This makes
856 * the graph much more legible, since whenever branches
857 * cross, only one is moving directions.
859 assert(target * 2 <= i);
861 if (target * 2 == i) {
863 * This column is already in the
864 * correct place
866 assert(graph->new_mapping[i] == -1);
867 graph->new_mapping[i] = target;
868 } else if (graph->new_mapping[i - 1] < 0) {
870 * Nothing is to the left.
871 * Move to the left by one
873 graph->new_mapping[i - 1] = target;
874 } else if (graph->new_mapping[i - 1] == target) {
876 * There is a branch line to our left
877 * already, and it is our target. We
878 * combine with this line, since we share
879 * the same parent commit.
881 * We don't have to add anything to the
882 * output or new_mapping, since the
883 * existing branch line has already taken
884 * care of it.
886 } else {
888 * There is a branch line to our left,
889 * but it isn't our target. We need to
890 * cross over it.
892 * The space just to the left of this
893 * branch should always be empty.
895 assert(graph->new_mapping[i - 1] > target);
896 assert(graph->new_mapping[i - 2] < 0);
897 graph->new_mapping[i - 2] = target;
902 * The new mapping may be 1 smaller than the old mapping
904 if (graph->new_mapping[graph->mapping_size - 1] < 0)
905 graph->mapping_size--;
908 * Output out a line based on the new mapping info
910 for (i = 0; i < graph->mapping_size; i++) {
911 int target = graph->new_mapping[i];
912 if (target < 0)
913 strbuf_addch(sb, ' ');
914 else if (target * 2 == i)
915 strbuf_addch(sb, '|');
916 else
917 strbuf_addch(sb, '/');
920 graph_pad_horizontally(graph, sb);
923 * Swap mapping and new_mapping
925 tmp_mapping = graph->mapping;
926 graph->mapping = graph->new_mapping;
927 graph->new_mapping = tmp_mapping;
930 * If graph->mapping indicates that all of the branch lines
931 * are already in the correct positions, we are done.
932 * Otherwise, we need to collapse some branch lines together.
934 if (graph_is_mapping_correct(graph))
935 graph_update_state(graph, GRAPH_PADDING);
938 static int graph_next_line(struct git_graph *graph, struct strbuf *sb)
940 switch (graph->state) {
941 case GRAPH_PADDING:
942 graph_output_padding_line(graph, sb);
943 return 0;
944 case GRAPH_SKIP:
945 graph_output_skip_line(graph, sb);
946 return 0;
947 case GRAPH_PRE_COMMIT:
948 graph_output_pre_commit_line(graph, sb);
949 return 0;
950 case GRAPH_COMMIT:
951 graph_output_commit_line(graph, sb);
952 return 1;
953 case GRAPH_POST_MERGE:
954 graph_output_post_merge_line(graph, sb);
955 return 0;
956 case GRAPH_COLLAPSING:
957 graph_output_collapsing_line(graph, sb);
958 return 0;
961 assert(0);
962 return 0;
965 static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
967 int i, j;
969 if (graph->state != GRAPH_COMMIT) {
970 graph_next_line(graph, sb);
971 return;
975 * Output the row containing this commit
976 * Iterate up to and including graph->num_columns,
977 * since the current commit may not be in any of the existing
978 * columns. (This happens when the current commit doesn't have any
979 * children that we have already processed.)
981 for (i = 0; i < graph->num_columns; i++) {
982 struct commit *col_commit = graph->columns[i].commit;
983 if (col_commit == graph->commit) {
984 strbuf_addch(sb, '|');
986 if (graph->num_parents < 3)
987 strbuf_addch(sb, ' ');
988 else {
989 int num_spaces = ((graph->num_parents - 2) * 2);
990 for (j = 0; j < num_spaces; j++)
991 strbuf_addch(sb, ' ');
993 } else {
994 strbuf_addstr(sb, "| ");
998 graph_pad_horizontally(graph, sb);
1001 * Update graph->prev_state since we have output a padding line
1003 graph->prev_state = GRAPH_PADDING;
1006 int graph_is_commit_finished(struct git_graph const *graph)
1008 return (graph->state == GRAPH_PADDING);
1011 void graph_show_commit(struct git_graph *graph)
1013 struct strbuf msgbuf = STRBUF_INIT;
1014 int shown_commit_line = 0;
1016 if (!graph)
1017 return;
1019 while (!shown_commit_line) {
1020 shown_commit_line = graph_next_line(graph, &msgbuf);
1021 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1022 if (!shown_commit_line)
1023 putchar('\n');
1024 strbuf_setlen(&msgbuf, 0);
1027 strbuf_release(&msgbuf);
1030 void graph_show_oneline(struct git_graph *graph)
1032 struct strbuf msgbuf = STRBUF_INIT;
1034 if (!graph)
1035 return;
1037 graph_next_line(graph, &msgbuf);
1038 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1039 strbuf_release(&msgbuf);
1042 void graph_show_padding(struct git_graph *graph)
1044 struct strbuf msgbuf = STRBUF_INIT;
1046 if (!graph)
1047 return;
1049 graph_padding_line(graph, &msgbuf);
1050 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1051 strbuf_release(&msgbuf);
1054 int graph_show_remainder(struct git_graph *graph)
1056 struct strbuf msgbuf = STRBUF_INIT;
1057 int shown = 0;
1059 if (!graph)
1060 return 0;
1062 if (graph_is_commit_finished(graph))
1063 return 0;
1065 for (;;) {
1066 graph_next_line(graph, &msgbuf);
1067 fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout);
1068 strbuf_setlen(&msgbuf, 0);
1069 shown = 1;
1071 if (!graph_is_commit_finished(graph))
1072 putchar('\n');
1073 else
1074 break;
1076 strbuf_release(&msgbuf);
1078 return shown;
1082 static void graph_show_strbuf(struct git_graph *graph, struct strbuf const *sb)
1084 char *p;
1086 if (!graph) {
1087 fwrite(sb->buf, sizeof(char), sb->len, stdout);
1088 return;
1092 * Print the strbuf line by line,
1093 * and display the graph info before each line but the first.
1095 p = sb->buf;
1096 while (p) {
1097 size_t len;
1098 char *next_p = strchr(p, '\n');
1099 if (next_p) {
1100 next_p++;
1101 len = next_p - p;
1102 } else {
1103 len = (sb->buf + sb->len) - p;
1105 fwrite(p, sizeof(char), len, stdout);
1106 if (next_p && *next_p != '\0')
1107 graph_show_oneline(graph);
1108 p = next_p;
1112 void graph_show_commit_msg(struct git_graph *graph,
1113 struct strbuf const *sb)
1115 int newline_terminated;
1117 if (!graph) {
1119 * If there's no graph, just print the message buffer.
1121 * The message buffer for CMIT_FMT_ONELINE and
1122 * CMIT_FMT_USERFORMAT are already missing a terminating
1123 * newline. All of the other formats should have it.
1125 fwrite(sb->buf, sizeof(char), sb->len, stdout);
1126 return;
1129 newline_terminated = (sb->len && sb->buf[sb->len - 1] == '\n');
1132 * Show the commit message
1134 graph_show_strbuf(graph, sb);
1137 * If there is more output needed for this commit, show it now
1139 if (!graph_is_commit_finished(graph)) {
1141 * If sb doesn't have a terminating newline, print one now,
1142 * so we can start the remainder of the graph output on a
1143 * new line.
1145 if (!newline_terminated)
1146 putchar('\n');
1148 graph_show_remainder(graph);
1151 * If sb ends with a newline, our output should too.
1153 if (newline_terminated)
1154 putchar('\n');