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_write_column(sb, &graph->new_columns[i], '|');
strbuf_addch(sb, ' ');
}
graph_pad_horizontally(graph, sb, graph->num_new_columns * 2);
}
static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
{
int i;
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 column *col = &graph->columns[i];
strbuf_write_column(sb, col, '|');
if (col->commit == graph->commit && graph->num_parents > 2)
strbuf_addchars(sb, ' ', (graph->num_parents - 2) * 2);
else
strbuf_addch(sb, ' ');
}
graph_pad_horizontally(graph, sb, graph->num_columns);
/*
* Update graph->prev_state since we have output a padding line
*/
graph->prev_state = GRAPH_PADDING;
}
/*
* Draw an octopus merge and return the number of characters written.
*/
static int graph_draw_octopus_merge(struct git_graph *graph,
struct strbuf *sb)
{
/*
* Here dashless_commits represents the number of parents
* which don't need to have dashes (because their edges fit
* neatly under the commit).
*/
const int dashless_commits = 2;
int col_num, i;
int num_dashes =
((graph->num_parents - dashless_commits) * 2) - 1;
for (i = 0; i < num_dashes; i++) {
col_num = (i / 2) + dashless_commits;
strbuf_write_column(sb, &graph->new_columns[col_num], '-');
}
col_num = (i / 2) + dashless_commits;
strbuf_write_column(sb, &graph->new_columns[col_num], '.');
return num_dashes + 1;
}
static void graph_output_collapsing_line(struct git_graph *graph, struct strbuf *sb)
{
int i;
int *tmp_mapping;
short used_horizontal = 0;
int horizontal_edge = -1;
int horizontal_edge_target = -1;
/*
* 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;
/*
* If there isn't already an edge moving horizontally
* select this one.
*/
if (horizontal_edge == -1) {
int j;
horizontal_edge = i;
horizontal_edge_target = target;
/*
* The variable target is the index of the graph
* column, and therefore target*2+3 is the
* actual screen column of the first horizontal
* line.
*/
for (j = (target * 2)+3; j < (i - 2); j += 2)
graph->new_mapping[j] = 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.
*
* The branch to the left of that space
* should be our eventual target.
*/
assert(graph->new_mapping[i - 1] > target);
assert(graph->new_mapping[i - 2] < 0);
assert(graph->new_mapping[i - 3] == target);
graph->new_mapping[i - 2] = target;
/*
* Mark this branch as the horizontal edge to
* prevent any other edges from moving
* horizontally.
*/
if (horizontal_edge == -1)
horizontal_edge = i;
}
}
/*
* 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_write_column(sb, &graph->new_columns[target], '|');
else if (target == horizontal_edge_target &&
i != horizontal_edge - 1) {
/*
* Set the mappings for all but the
* first segment to -1 so that they
* won't continue into the next line.
*/
if (i != (target * 2)+3)
graph->new_mapping[i] = -1;
used_horizontal = 1;
strbuf_write_column(sb, &graph->new_columns[target], '_');
} else {
if (used_horizontal && i < horizontal_edge)
graph->new_mapping[i] = -1;
strbuf_write_column(sb, &graph->new_columns[target], '/');
}
}
graph_pad_horizontally(graph, sb, graph->mapping_size);
/*
* 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_update_state(graph, GRAPH_PADDING);
}
static void graph_output_post_merge_line(struct git_graph *graph, struct strbuf *sb)
{
int seen_this = 0;
int i, j, chars_written;
/*
* Output the post-merge row
*/
chars_written = 0;
for (i = 0; i <= graph->num_columns; i++) {
struct column *col = &graph->columns[i];
struct commit *col_commit;
if (i == graph->num_columns) {
if (seen_this)
break;
col_commit = graph->commit;
} else {
col_commit = col->commit;
}
if (col_commit == graph->commit) {
/*
* Since the current commit is a merge find
* the columns for the parent commits in
* new_columns and use those to format the
* edges.
*/
struct commit_list *parents = NULL;
struct column *par_column;
seen_this = 1;
parents = first_interesting_parent(graph);
assert(parents);
par_column = find_new_column_by_commit(graph, parents->item);
assert(par_column);
strbuf_write_column(sb, par_column, '|');
chars_written++;
for (j = 0; j < graph->num_parents - 1; j++) {
parents = next_interesting_parent(graph, parents);
assert(parents);
par_column = find_new_column_by_commit(graph, parents->item);
assert(par_column);
strbuf_write_column(sb, par_column, '\\');
strbuf_addch(sb, ' ');
}
chars_written += j * 2;
} else if (seen_this) {
strbuf_write_column(sb, col, '\\');
strbuf_addch(sb, ' ');
chars_written += 2;
} else {
strbuf_write_column(sb, col, '|');
strbuf_addch(sb, ' ');
chars_written += 2;
}
}
graph_pad_horizontally(graph, sb, chars_written);
/*
* Update graph->state
*/
if (graph_is_mapping_correct(graph))
graph_update_state(graph, GRAPH_PADDING);
else
graph_update_state(graph, GRAPH_COLLAPSING);
}
static void graph_output_commit_line(struct git_graph *graph, struct strbuf *sb)
{
int seen_this = 0;
int i, chars_written;
/*
* 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;
chars_written = 0;
for (i = 0; i <= graph->num_columns; i++) {
struct column *col = &graph->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;
graph_output_commit_char(graph, sb);
chars_written++;
if (graph->num_parents > 2)
chars_written += graph_draw_octopus_merge(graph,
sb);
} else if (seen_this && (graph->num_parents > 2)) {
strbuf_write_column(sb, col, '\\');
chars_written++;
} else if (seen_this && (graph->num_parents == 2)) {
/*
* This is a 2-way merge commit.
* There is no GRAPH_PRE_COMMIT stage for 2-way
* merges, so this is the first line of output
* for this commit. Check to see what the previous
* line of output was.
*
* If it was GRAPH_POST_MERGE, the branch line
* coming into this commit may have been '\',
* and not '|' or '/'. If so, output the branch
* line as '\' on this line, instead of '|'. This
* makes the output look nicer.
*/
if (graph->prev_state == GRAPH_POST_MERGE &&
graph->prev_commit_index < i)
strbuf_write_column(sb, col, '\\');
else
strbuf_write_column(sb, col, '|');
chars_written++;
} else {
strbuf_write_column(sb, col, '|');
chars_written++;
}
strbuf_addch(sb, ' ');
chars_written++;
}
graph_pad_horizontally(graph, sb, chars_written);
/*
* Update graph->state
*/
if (graph->num_parents > 1)
graph_update_state(graph, GRAPH_POST_MERGE);
else if (graph_is_mapping_correct(graph))
graph_update_state(graph, GRAPH_PADDING);
else
graph_update_state(graph, GRAPH_COLLAPSING);
}
static void graph_output_pre_commit_line(struct git_graph *graph,
struct strbuf *sb)
{
int num_expansion_rows;
int i, seen_this;
int chars_written;
/*
* 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;
chars_written = 0;
for (i = 0; i < graph->num_columns; i++) {
struct column *col = &graph->columns[i];
if (col->commit == graph->commit) {
seen_this = 1;
strbuf_write_column(sb, col, '|');
strbuf_addf(sb, "%*s", graph->expansion_row, "");
chars_written += 1 + graph->expansion_row;
} else if (seen_this && (graph->expansion_row == 0)) {
/*
* This is the first line of the pre-commit output.
* If the previous commit was a merge commit and
* ended in the GRAPH_POST_MERGE state, all branch
* lines after graph->prev_commit_index were
* printed as "\" on the previous line. Continue
* to print them as "\" on this line. Otherwise,
* print the branch lines as "|".
*/
if (graph->prev_state == GRAPH_POST_MERGE &&
graph->prev_commit_index < i)
strbuf_write_column(sb, col, '\\');
else
strbuf_write_column(sb, col, '|');
chars_written++;
} else if (seen_this && (graph->expansion_row > 0)) {
strbuf_write_column(sb, col, '\\');
chars_written++;
} else {
strbuf_write_column(sb, col, '|');
chars_written++;
}
strbuf_addch(sb, ' ');
chars_written++;
}
graph_pad_horizontally(graph, sb, chars_written);
/*
* Increment graph->expansion_row,
* and move to state GRAPH_COMMIT if necessary
*/
graph->expansion_row++;
if (graph->expansion_row >= num_expansion_rows)
graph_update_state(graph, GRAPH_COMMIT);
}