#include "cache.h" #include "commit.h" #include "graph.h" #include "diff.h" #include "revision.h" /* * TODO: * - Add colors to the graph. * Pick a color for each column, and print all characters * in that column with the specified color. * * - Limit the number of columns, similar to the way gitk does. * If we reach more than a specified number of columns, omit * sections of some columns. * * - The output during the GRAPH_PRE_COMMIT and GRAPH_COLLAPSING states * could be made more compact by printing horizontal lines, instead of * long diagonal lines. For example, during collapsing, something like * this: instead of this: * | | | | | | | | | | * | |_|_|/ | | | |/ * |/| | | | | |/| * | | | | | |/| | * |/| | | * | | | | * * If there are several parallel diagonal lines, they will need to be * replaced with horizontal lines on subsequent rows. */ struct column { /* * The parent commit of this column. */ struct commit *commit; /* * XXX: Once we add support for colors, struct column could also * contain the color of its branch line. */ }; enum graph_state { GRAPH_PADDING, GRAPH_SKIP, GRAPH_PRE_COMMIT, GRAPH_COMMIT, GRAPH_POST_MERGE, GRAPH_COLLAPSING }; struct git_graph { /* * The commit currently being processed */ struct commit *commit; /* * The number of parents this commit has. * (Stored so we don't have to walk over them each time we need * this number) */ int num_parents; /* * The width of the graph output for this commit. * All rows for this commit are padded to this width, so that * messages printed after the graph output are aligned. */ int width; /* * The next expansion row to print * when state is GRAPH_PRE_COMMIT */ int expansion_row; /* * The current output state. * This tells us what kind of line graph_next_line() should output. */ enum graph_state state; /* * The maximum number of columns that can be stored in the columns * and new_columns arrays. This is also half the number of entries * that can be stored in the mapping and new_mapping arrays. */ int column_capacity; /* * The number of columns (also called "branch lines" in some places) */ int num_columns; /* * The number of columns in the new_columns array */ int num_new_columns; /* * The number of entries in the mapping array */ int mapping_size; /* * The column state before we output the current commit. */ struct column *columns; /* * The new column state after we output the current commit. * Only valid when state is GRAPH_COLLAPSING. */ struct column *new_columns; /* * An array that tracks the current state of each * character in the output line during state GRAPH_COLLAPSING. * Each entry is -1 if this character is empty, or a non-negative * integer if the character contains a branch line. The value of * the integer indicates the target position for this branch line. * (I.e., this array maps the current column positions to their * desired positions.) * * The maximum capacity of this array is always * sizeof(int) * 2 * column_capacity. */ int *mapping; /* * A temporary array for computing the next mapping state * while we are outputting a mapping line. This is stored as part * of the git_graph simply so we don't have to allocate a new * temporary array each time we have to output a collapsing line. */ int *new_mapping; }; struct git_graph *graph_init(void) { struct git_graph *graph = xmalloc(sizeof(struct git_graph)); graph->commit = NULL; graph->num_parents = 0; graph->expansion_row = 0; graph->state = GRAPH_PADDING; graph->num_columns = 0; graph->num_new_columns = 0; graph->mapping_size = 0; /* * Allocate a reasonably large default number of columns * We'll automatically grow columns later if we need more room. */ graph->column_capacity = 30; graph->columns = xmalloc(sizeof(struct column) * graph->column_capacity); graph->new_columns = xmalloc(sizeof(struct column) * graph->column_capacity); graph->mapping = xmalloc(sizeof(int) * 2 * graph->column_capacity); graph->new_mapping = xmalloc(sizeof(int) * 2 * graph->column_capacity); return graph; } void graph_release(struct git_graph *graph) { free(graph->columns); free(graph->new_columns); free(graph->mapping); free(graph); } static void graph_ensure_capacity(struct git_graph *graph, int num_columns) { if (graph->column_capacity >= num_columns) return; do { graph->column_capacity *= 2; } while (graph->column_capacity < num_columns); graph->columns = xrealloc(graph->columns, sizeof(struct column) * graph->column_capacity); graph->new_columns = xrealloc(graph->new_columns, sizeof(struct column) * graph->column_capacity); graph->mapping = xrealloc(graph->mapping, sizeof(int) * 2 * graph->column_capacity); graph->new_mapping = xrealloc(graph->new_mapping, sizeof(int) * 2 * graph->column_capacity); } static void graph_insert_into_new_columns(struct git_graph *graph, struct commit *commit, int *mapping_index) { int i; /* * Ignore uinteresting and pruned commits */ if (commit->object.flags & (UNINTERESTING | TREESAME)) return; /* * If the commit is already in the new_columns list, we don't need to * add it. Just update the mapping correctly. */ for (i = 0; i < graph->num_new_columns; i++) { if (graph->new_columns[i].commit == commit) { graph->mapping[*mapping_index] = i; *mapping_index += 2; return; } } /* * This commit isn't already in new_columns. Add it. */ graph->new_columns[graph->num_new_columns].commit = commit; graph->mapping[*mapping_index] = graph->num_new_columns; *mapping_index += 2; graph->num_new_columns++; } static void graph_update_width(struct git_graph *graph, int is_commit_in_existing_columns) { /* * Compute the width needed to display the graph for this commit. * This is the maximum width needed for any row. All other rows * will be padded to this width. * * Compute the number of columns in the widest row: * Count each existing column (graph->num_columns), and each new * column added by this commit. */ int max_cols = graph->num_columns + graph->num_parents; /* * Even if the current commit has no parents, it still takes up a * column for itself. */ if (graph->num_parents < 1) max_cols++; /* * We added a column for the the current commit as part of * graph->num_parents. If the current commit was already in * graph->columns, then we have double counted it. */ if (is_commit_in_existing_columns) max_cols--; /* * Each column takes up 2 spaces */ graph->width = max_cols * 2; } static void graph_update_columns(struct git_graph *graph) { struct commit_list *parent; struct column *tmp_columns; int max_new_columns; int mapping_idx; int i, seen_this, is_commit_in_columns; /* * Swap graph->columns with graph->new_columns * graph->columns contains the state for the previous commit, * and new_columns now contains the state for our commit. * * We'll re-use the old columns array as storage to compute the new * columns list for the commit after this one. */ tmp_columns = graph->columns; graph->columns = graph->new_columns; graph->num_columns = graph->num_new_columns; graph->new_columns = tmp_columns; graph->num_new_columns = 0; /* * Now update new_columns and mapping with the information for the * commit after this one. * * First, make sure we have enough room. At most, there will * be graph->num_columns + graph->num_parents columns for the next * commit. */ max_new_columns = graph->num_columns + graph->num_parents; graph_ensure_capacity(graph, max_new_columns); /* * Clear out graph->mapping */ graph->mapping_size = 2 * max_new_columns; for (i = 0; i < graph->mapping_size; i++) graph->mapping[i] = -1; /* * Populate graph->new_columns and graph->mapping * * Some of the parents of this commit may already be in * graph->columns. If so, graph->new_columns should only contain a * single entry for each such commit. graph->mapping should * contain information about where each current branch line is * supposed to end up after the collapsing is performed. */ seen_this = 0; mapping_idx = 0; is_commit_in_columns = 1; for (i = 0; i <= graph->num_columns; i++) { struct commit *col_commit; if (i == graph->num_columns) { if (seen_this) break; is_commit_in_columns = 0; col_commit = graph->commit; } else { col_commit = graph->columns[i].commit; } if (col_commit == graph->commit) { seen_this = 1; for (parent = graph->commit->parents; parent; parent = parent->next) { graph_insert_into_new_columns(graph, parent->item, &mapping_idx); } } else { graph_insert_into_new_columns(graph, col_commit, &mapping_idx); } } /* * Shrink mapping_size to be the minimum necessary */ while (graph->mapping_size > 1 && graph->mapping[graph->mapping_size - 1] < 0) graph->mapping_size--; /* * Compute graph->width for this commit */ graph_update_width(graph, is_commit_in_columns); } void graph_update(struct git_graph *graph, struct commit *commit) { struct commit_list *parent; /* * Set the new commit */ graph->commit = commit; /* * Count how many parents this commit has */ graph->num_parents = 0; for (parent = commit->parents; parent; parent = parent->next) graph->num_parents++; /* * Call graph_update_columns() to update * columns, new_columns, and mapping. */ graph_update_columns(graph); graph->expansion_row = 0; /* * Update graph->state. * * If the previous commit didn't get to the GRAPH_PADDING state, * it never finished its output. Goto GRAPH_SKIP, to print out * a line to indicate that portion of the graph is missing. * * Otherwise, if there are 3 or more parents, we need to print * extra rows before the commit, to expand the branch lines around * it and make room for it. * * If there are less than 3 parents, we can immediately print the * commit line. */ if (graph->state != GRAPH_PADDING) graph->state = GRAPH_SKIP; else if (graph->num_parents >= 3) graph->state = GRAPH_PRE_COMMIT; else graph->state = GRAPH_COMMIT; } static int graph_is_mapping_correct(struct git_graph *graph) { int i; /* * The mapping is up to date if each entry is at its target, * or is 1 greater than its target. * (If it is 1 greater than the target, '/' will be printed, so it * will look correct on the next row.) */ for (i = 0; i < graph->mapping_size; i++) { int target = graph->mapping[i]; if (target < 0) continue; if (target == (i / 2)) continue; return 0; } return 1; } static void graph_pad_horizontally(struct git_graph *graph, struct strbuf *sb) { /* * Add additional spaces to the end of the strbuf, so that all * lines for a particular commit have the same width. * * This way, fields printed to the right of the graph will remain * aligned for the entire commit. */ int extra; if (sb->len >= graph->width) return; extra = graph->width - sb->len; strbuf_addf(sb, "%*s", (int) extra, ""); } static void graph_output_padding_line(struct git_graph *graph, struct strbuf *sb) { int i; /* * We could conceivable be called with a NULL commit * if our caller has a bug, and invokes graph_next_line() * immediately after graph_init(), without first calling * graph_update(). Return without outputting anything in this * case. */ if (!graph->commit) return; /* * Output a padding row, that leaves all branch lines unchanged */ for (i = 0; i < graph->num_new_columns; i++) { strbuf_addstr(sb, "| "); } graph_pad_horizontally(graph, sb); } static void graph_output_skip_line(struct git_graph *graph, struct strbuf *sb) { /* * Output an ellipsis to indicate that a portion * of the graph is missing. */ strbuf_addstr(sb, "..."); graph_pad_horizontally(graph, sb); if (graph->num_parents >= 3) graph->state = GRAPH_PRE_COMMIT; else graph->state = GRAPH_COMMIT; } static void graph_output_pre_commit_line(struct git_graph *graph, struct strbuf *sb) { int num_expansion_rows; int i, seen_this; /* * This function formats a row that increases the space around a commit * with multiple parents, to make room for it. It should only be * called when there are 3 or more parents. * * We need 2 extra rows for every parent over 2. */ assert(graph->num_parents >= 3); num_expansion_rows = (graph->num_parents - 2) * 2; /* * graph->expansion_row tracks the current expansion row we are on. * It should be in the range [0, num_expansion_rows - 1] */ assert(0 <= graph->expansion_row && graph->expansion_row < num_expansion_rows); /* * Output the row */ seen_this = 0; for (i = 0; i < graph->num_columns; i++) { struct column *col = &graph->columns[i]; if (col->commit == graph->commit) { seen_this = 1; strbuf_addf(sb, "| %*s", graph->expansion_row, ""); } else if (seen_this) { strbuf_addstr(sb, "\\ "); } else { strbuf_addstr(sb, "| "); } } graph_pad_horizontally(graph, sb); /* * Increment graph->expansion_row, * and move to state GRAPH_COMMIT if necessary */ graph->expansion_row++; if (graph->expansion_row >= num_expansion_rows) graph->state = GRAPH_COMMIT; } void graph_output_commit_line(struct git_graph *graph, struct strbuf *sb) { int seen_this = 0; int i, j; /* * Output the row containing this commit * Iterate up to and including graph->num_columns, * since the current commit may not be in any of the existing * columns. (This happens when the current commit doesn't have any * children that we have already processed.) */ seen_this = 0; for (i = 0; i <= graph->num_columns; i++) { struct commit *col_commit; if (i == graph->num_columns) { if (seen_this) break; col_commit = graph->commit; } else { col_commit = graph->columns[i].commit; } if (col_commit == graph->commit) { seen_this = 1; if (graph->num_parents > 1) strbuf_addch(sb, 'M'); else strbuf_addch(sb, '*'); if (graph->num_parents < 2) strbuf_addch(sb, ' '); else if (graph->num_parents == 2) strbuf_addstr(sb, " "); else { int num_dashes = ((graph->num_parents - 2) * 2) - 1; for (j = 0; j < num_dashes; j++) strbuf_addch(sb, '-'); strbuf_addstr(sb, ". "); } } else if (seen_this && (graph->num_parents > 1)) { strbuf_addstr(sb, "\\ "); } else { strbuf_addstr(sb, "| "); } } graph_pad_horizontally(graph, sb); /* * Update graph->state */ if (graph->num_parents > 1) graph->state = GRAPH_POST_MERGE; else if (graph_is_mapping_correct(graph)) graph->state = GRAPH_PADDING; else graph->state = GRAPH_COLLAPSING; } void graph_output_post_merge_line(struct git_graph *graph, struct strbuf *sb) { int seen_this = 0; int i, j; /* * Output the post-merge row */ for (i = 0; i <= graph->num_columns; i++) { struct commit *col_commit; if (i == graph->num_columns) { if (seen_this) break; col_commit = graph->commit; } else { col_commit = graph->columns[i].commit; } if (col_commit == graph->commit) { seen_this = 1; strbuf_addch(sb, '|'); for (j = 0; j < graph->num_parents - 1; j++) strbuf_addstr(sb, "\\ "); if (graph->num_parents == 2) strbuf_addch(sb, ' '); } else if (seen_this && (graph->num_parents > 2)) { strbuf_addstr(sb, "\\ "); } else { strbuf_addstr(sb, "| "); } } graph_pad_horizontally(graph, sb); /* * Update graph->state */ if (graph_is_mapping_correct(graph)) graph->state = GRAPH_PADDING; else graph->state = GRAPH_COLLAPSING; } void graph_output_collapsing_line(struct git_graph *graph, struct strbuf *sb) { int i; int *tmp_mapping; /* * Clear out the new_mapping array */ for (i = 0; i < graph->mapping_size; i++) graph->new_mapping[i] = -1; for (i = 0; i < graph->mapping_size; i++) { int target = graph->mapping[i]; if (target < 0) continue; /* * Since update_columns() always inserts the leftmost * column first, each branch's target location should * always be either its current location or to the left of * its current location. * * We never have to move branches to the right. This makes * the graph much more legible, since whenever branches * cross, only one is moving directions. */ assert(target * 2 <= i); if (target * 2 == i) { /* * This column is already in the * correct place */ assert(graph->new_mapping[i] == -1); graph->new_mapping[i] = target; } else if (graph->new_mapping[i - 1] < 0) { /* * Nothing is to the left. * Move to the left by one */ graph->new_mapping[i - 1] = target; } else if (graph->new_mapping[i - 1] == target) { /* * There is a branch line to our left * already, and it is our target. We * combine with this line, since we share * the same parent commit. * * We don't have to add anything to the * output or new_mapping, since the * existing branch line has already taken * care of it. */ } else { /* * There is a branch line to our left, * but it isn't our target. We need to * cross over it. * * The space just to the left of this * branch should always be empty. */ assert(graph->new_mapping[i - 1] > target); assert(graph->new_mapping[i - 2] < 0); graph->new_mapping[i - 2] = target; } } /* * The new mapping may be 1 smaller than the old mapping */ if (graph->new_mapping[graph->mapping_size - 1] < 0) graph->mapping_size--; /* * Output out a line based on the new mapping info */ for (i = 0; i < graph->mapping_size; i++) { int target = graph->new_mapping[i]; if (target < 0) strbuf_addch(sb, ' '); else if (target * 2 == i) strbuf_addch(sb, '|'); else strbuf_addch(sb, '/'); } graph_pad_horizontally(graph, sb); /* * Swap mapping and new_mapping */ tmp_mapping = graph->mapping; graph->mapping = graph->new_mapping; graph->new_mapping = tmp_mapping; /* * If graph->mapping indicates that all of the branch lines * are already in the correct positions, we are done. * Otherwise, we need to collapse some branch lines together. */ if (graph_is_mapping_correct(graph)) graph->state = GRAPH_PADDING; } int graph_next_line(struct git_graph *graph, struct strbuf *sb) { switch (graph->state) { case GRAPH_PADDING: graph_output_padding_line(graph, sb); return 0; case GRAPH_SKIP: graph_output_skip_line(graph, sb); return 0; case GRAPH_PRE_COMMIT: graph_output_pre_commit_line(graph, sb); return 0; case GRAPH_COMMIT: graph_output_commit_line(graph, sb); return 1; case GRAPH_POST_MERGE: graph_output_post_merge_line(graph, sb); return 0; case GRAPH_COLLAPSING: graph_output_collapsing_line(graph, sb); return 0; } assert(0); return 0; } void graph_padding_line(struct git_graph *graph, struct strbuf *sb) { int i, j; if (graph->state != GRAPH_COMMIT) { graph_next_line(graph, sb); return; } /* * Output the row containing this commit * Iterate up to and including graph->num_columns, * since the current commit may not be in any of the existing * columns. (This happens when the current commit doesn't have any * children that we have already processed.) */ for (i = 0; i < graph->num_columns; i++) { struct commit *col_commit = graph->columns[i].commit; if (col_commit == graph->commit) { strbuf_addch(sb, '|'); if (graph->num_parents < 3) strbuf_addch(sb, ' '); else { int num_spaces = ((graph->num_parents - 2) * 2); for (j = 0; j < num_spaces; j++) strbuf_addch(sb, ' '); } } else { strbuf_addstr(sb, "| "); } } graph_pad_horizontally(graph, sb); } int graph_is_commit_finished(struct git_graph const *graph) { return (graph->state == GRAPH_PADDING); } void graph_show_commit(struct git_graph *graph) { struct strbuf msgbuf; int shown_commit_line = 0; if (!graph) return; strbuf_init(&msgbuf, 0); while (!shown_commit_line) { shown_commit_line = graph_next_line(graph, &msgbuf); fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout); if (!shown_commit_line) putchar('\n'); strbuf_setlen(&msgbuf, 0); } strbuf_release(&msgbuf); } void graph_show_oneline(struct git_graph *graph) { struct strbuf msgbuf; if (!graph) return; strbuf_init(&msgbuf, 0); graph_next_line(graph, &msgbuf); fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout); strbuf_release(&msgbuf); } void graph_show_padding(struct git_graph *graph) { struct strbuf msgbuf; if (!graph) return; strbuf_init(&msgbuf, 0); graph_padding_line(graph, &msgbuf); fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout); strbuf_release(&msgbuf); } int graph_show_remainder(struct git_graph *graph) { struct strbuf msgbuf; int shown = 0; if (!graph) return 0; if (graph_is_commit_finished(graph)) return 0; strbuf_init(&msgbuf, 0); for (;;) { graph_next_line(graph, &msgbuf); fwrite(msgbuf.buf, sizeof(char), msgbuf.len, stdout); strbuf_setlen(&msgbuf, 0); shown = 1; if (!graph_is_commit_finished(graph)) putchar('\n'); else break; } strbuf_release(&msgbuf); return shown; } void graph_show_strbuf(struct git_graph *graph, struct strbuf const *sb) { char *p; if (!graph) { fwrite(sb->buf, sizeof(char), sb->len, stdout); return; } /* * Print the strbuf line by line, * and display the graph info before each line but the first. */ p = sb->buf; while (p) { size_t len; char *next_p = strchr(p, '\n'); if (next_p) { next_p++; len = next_p - p; } else { len = (sb->buf + sb->len) - p; } fwrite(p, sizeof(char), len, stdout); if (next_p && *next_p != '\0') graph_show_oneline(graph); p = next_p; } } void graph_show_commit_msg(struct git_graph *graph, struct strbuf const *sb) { int newline_terminated; if (!graph) { /* * If there's no graph, just print the message buffer. * * The message buffer for CMIT_FMT_ONELINE and * CMIT_FMT_USERFORMAT are already missing a terminating * newline. All of the other formats should have it. */ fwrite(sb->buf, sizeof(char), sb->len, stdout); return; } newline_terminated = (sb->len && sb->buf[sb->len - 1] == '\n'); /* * Show the commit message */ graph_show_strbuf(graph, sb); /* * If there is more output needed for this commit, show it now */ if (!graph_is_commit_finished(graph)) { /* * If sb doesn't have a terminating newline, print one now, * so we can start the remainder of the graph output on a * new line. */ if (!newline_terminated) putchar('\n'); graph_show_remainder(graph); /* * If sb ends with a newline, our output should too. */ if (newline_terminated) putchar('\n'); } }