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#include "cache.h"
#include "config.h"
#include "commit.h"
#include "color.h"
#include "graph.h"
#include "revision.h"
#include "strvec.h"
/* Internal API */
/*
* Output a padding line in the graph.
* This is similar to graph_next_line(). However, it is guaranteed to
* never print the current commit line. Instead, if the commit line is
* next, it will simply output a line of vertical padding, extending the
* branch lines downwards, but leaving them otherwise unchanged.
*/
static void graph_padding_line(struct git_graph *graph, struct strbuf *sb);
/*
* Print a strbuf. If the graph is non-NULL, all lines but the first will be
* prefixed with the graph output.
*
* If the strbuf ends with a newline, the output will end after this
* newline. A new graph line will not be printed after the final newline.
* If the strbuf is empty, no output will be printed.
*
* Since the first line will not include the graph output, the caller is
* responsible for printing this line's graph (perhaps via
* graph_show_commit() or graph_show_oneline()) before calling
* graph_show_strbuf().
*
* Note that unlike some other graph display functions, you must pass the file
* handle directly. It is assumed that this is the same file handle as the
* file specified by the graph diff options. This is necessary so that
* graph_show_strbuf can be called even with a NULL graph.
* If a NULL graph is supplied, the strbuf is printed as-is.
*/
static void graph_show_strbuf(struct git_graph *graph,
FILE *file,
struct strbuf const *sb);
/*
* TODO:
* - 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.
*/
struct column {
/*
* The parent commit of this column.
*/
struct commit *commit;
/*
* The color to (optionally) print this column in. This is an
* index into column_colors.
*/
unsigned short color;
};
enum graph_state {
GRAPH_PADDING,
GRAPH_SKIP,
GRAPH_PRE_COMMIT,
GRAPH_COMMIT,
GRAPH_POST_MERGE,
GRAPH_COLLAPSING
};
static void graph_show_line_prefix(const struct diff_options *diffopt)
{
if (!diffopt || !diffopt->line_prefix)
return;
fwrite(diffopt->line_prefix,
sizeof(char),
diffopt->line_prefix_length,
diffopt->file);
}
static const char **column_colors;
static unsigned short column_colors_max;
static void parse_graph_colors_config(struct strvec *colors, const char *string)
{
const char *end, *start;
start = string;
end = string + strlen(string);
while (start < end) {
const char *comma = strchrnul(start, ',');
char color[COLOR_MAXLEN];
if (!color_parse_mem(start, comma - start, color))
strvec_push(colors, color);
else
warning(_("ignored invalid color '%.*s' in log.graphColors"),
(int)(comma - start), start);
start = comma + 1;
}
strvec_push(colors, GIT_COLOR_RESET);
}
void graph_set_column_colors(const char **colors, unsigned short colors_max)
{
column_colors = colors;
column_colors_max = colors_max;
}
static const char *column_get_color_code(unsigned short color)
{
return column_colors[color];
}
struct graph_line {
struct strbuf *buf;
size_t width;
};
static inline void graph_line_addch(struct graph_line *line, int c)
{
strbuf_addch(line->buf, c);
line->width++;
}
static inline void graph_line_addchars(struct graph_line *line, int c, size_t n)
{
strbuf_addchars(line->buf, c, n);
line->width += n;
}
static inline void graph_line_addstr(struct graph_line *line, const char *s)
{
strbuf_addstr(line->buf, s);
line->width += strlen(s);
}
static inline void graph_line_addcolor(struct graph_line *line, unsigned short color)
{
strbuf_addstr(line->buf, column_get_color_code(color));
}
static void graph_line_write_column(struct graph_line *line, const struct column *c,
char col_char)
{
if (c->color < column_colors_max)
graph_line_addcolor(line, c->color);
graph_line_addch(line, col_char);
if (c->color < column_colors_max)
graph_line_addcolor(line, column_colors_max);
}
struct git_graph {
/*
* The commit currently being processed
*/
struct commit *commit;
/* The rev-info used for the current traversal */
struct rev_info *revs;
/*
* The number of interesting parents that this commit has.
*
* Note that this is not the same as the actual number of parents.
* This count excludes parents that won't be printed in the graph
* output, as determined by graph_is_interesting().
*/
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 output state for the previous line of output.
* This is primarily used to determine how the first merge line
* should appear, based on the last line of the previous commit.
*/
enum graph_state prev_state;
/*
* The index of the column that refers to this commit.
*
* If none of the incoming columns refer to this commit,
* this will be equal to num_columns.
*/
int commit_index;
/*
* The commit_index for the previously displayed commit.
*
* This is used to determine how the first line of a merge
* graph output should appear, based on the last line of the
* previous commit.
*/
int prev_commit_index;
/*
* Which layout variant to use to display merge commits. If the
* commit's first parent is known to be in a column to the left of the
* merge, then this value is 0 and we use the layout on the left.
* Otherwise, the value is 1 and the layout on the right is used. This
* field tells us how many columns the first parent occupies.
*
* 0) 1)
*
* | | | *-. | | *---.
* | |_|/|\ \ | | |\ \ \
* |/| | | | | | | | | | *
*/
int merge_layout;
/*
* The number of columns added to the graph by the current commit. For
* 2-way and octopus merges, this is usually one less than the
* number of parents:
*
* | | | | | \
* | * | | *---. \
* | |\ \ | |\ \ \ \
* | | | | | | | | | |
*
* num_parents: 2 num_parents: 4
* edges_added: 1 edges_added: 3
*
* For left-skewed merges, the first parent fuses with its neighbor and
* so one less column is added:
*
* | | | | | \
* | * | | *-. \
* |/| | |/|\ \ \
* | | | | | | | |
*
* num_parents: 2 num_parents: 4
* edges_added: 0 edges_added: 2
*
* This number determines how edges to the right of the merge are
* displayed in commit and post-merge lines; if no columns have been
* added then a vertical line should be used where a right-tracking
* line would otherwise be used.
*
* | * \ | * |
* | |\ \ |/| |
* | | * \ | * |
*/
int edges_added;
/*
* The number of columns added by the previous commit, which is used to
* smooth edges appearing to the right of a commit in a commit line
* following a post-merge line.
*/
int prev_edges_added;
/*
* 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 old_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 copy of the contents of the mapping array from the last commit,
* which we use to improve the display of columns that are tracking
* from right to left through a commit line. We also use this to
* avoid allocating a fresh array when we compute the next mapping.
*/
int *old_mapping;
/*
* The current default column color being used. This is
* stored as an index into the array column_colors.
*/
unsigned short default_column_color;
};
static struct strbuf *diff_output_prefix_callback(struct diff_options *opt, void *data)
{
struct git_graph *graph = data;
static struct strbuf msgbuf = STRBUF_INIT;
assert(opt);
strbuf_reset(&msgbuf);
if (opt->line_prefix)
strbuf_add(&msgbuf, opt->line_prefix,
opt->line_prefix_length);
if (graph)
graph_padding_line(graph, &msgbuf);
return &msgbuf;
}
static const struct diff_options *default_diffopt;
void graph_setup_line_prefix(struct diff_options *diffopt)
{
default_diffopt = diffopt;
/* setup an output prefix callback if necessary */
if (diffopt && !diffopt->output_prefix)
diffopt->output_prefix = diff_output_prefix_callback;
}
struct git_graph *graph_init(struct rev_info *opt)
{
struct git_graph *graph = xmalloc(sizeof(struct git_graph));
if (!column_colors) {
char *string;
if (git_config_get_string("log.graphcolors", &string)) {
/* not configured -- use default */
graph_set_column_colors(column_colors_ansi,
column_colors_ansi_max);
} else {
static struct strvec custom_colors = STRVEC_INIT;
strvec_clear(&custom_colors);
parse_graph_colors_config(&custom_colors, string);
free(string);
/* graph_set_column_colors takes a max-index, not a count */
graph_set_column_colors(custom_colors.v,
custom_colors.nr - 1);
}
}
graph->commit = NULL;
graph->revs = opt;
graph->num_parents = 0;
graph->expansion_row = 0;
graph->state = GRAPH_PADDING;
graph->prev_state = GRAPH_PADDING;
graph->commit_index = 0;
graph->prev_commit_index = 0;
graph->merge_layout = 0;
graph->edges_added = 0;
graph->prev_edges_added = 0;
graph->num_columns = 0;
graph->num_new_columns = 0;
graph->mapping_size = 0;
/*
* Start the column color at the maximum value, since we'll
* always increment it for the first commit we output.
* This way we start at 0 for the first commit.
*/
graph->default_column_color = column_colors_max - 1;
/*
* Allocate a reasonably large default number of columns
* We'll automatically grow columns later if we need more room.
*/
graph->column_capacity = 30;
ALLOC_ARRAY(graph->columns, graph->column_capacity);
ALLOC_ARRAY(graph->new_columns, graph->column_capacity);
ALLOC_ARRAY(graph->mapping, 2 * graph->column_capacity);
ALLOC_ARRAY(graph->old_mapping, 2 * graph->column_capacity);
/*
* The diff output prefix callback, with this we can make
* all the diff output to align with the graph lines.
*/
opt->diffopt.output_prefix = diff_output_prefix_callback;
opt->diffopt.output_prefix_data = graph;
return graph;
}
static void graph_update_state(struct git_graph *graph, enum graph_state s)
{
graph->prev_state = graph->state;
graph->state = s;
}
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);
REALLOC_ARRAY(graph->columns, graph->column_capacity);
REALLOC_ARRAY(graph->new_columns, graph->column_capacity);
REALLOC_ARRAY(graph->mapping, graph->column_capacity * 2);
REALLOC_ARRAY(graph->old_mapping, graph->column_capacity * 2);
}
/*
* Returns 1 if the commit will be printed in the graph output,
* and 0 otherwise.
*/
static int graph_is_interesting(struct git_graph *graph, struct commit *commit)
{
/*
* If revs->boundary is set, commits whose children have
* been shown are always interesting, even if they have the
* UNINTERESTING or TREESAME flags set.
*/
if (graph->revs && graph->revs->boundary) {
if (commit->object.flags & CHILD_SHOWN)
return 1;
}
/*
* Otherwise, use get_commit_action() to see if this commit is
* interesting
*/
return get_commit_action(graph->revs, commit) == commit_show;
}
static struct commit_list *next_interesting_parent(struct git_graph *graph,
struct commit_list *orig)
{
struct commit_list *list;
/*
* If revs->first_parent_only is set, only the first
* parent is interesting. None of the others are.
*/
if (graph->revs->first_parent_only)
return NULL;
/*
* Return the next interesting commit after orig
*/
for (list = orig->next; list; list = list->next) {
if (graph_is_interesting(graph, list->item))
return list;
}
return NULL;
}
static struct commit_list *first_interesting_parent(struct git_graph *graph)
{
struct commit_list *parents = graph->commit->parents;
/*
* If this commit has no parents, ignore it
*/
if (!parents)
return NULL;
/*
* If the first parent is interesting, return it
*/
if (graph_is_interesting(graph, parents->item))
return parents;
/*
* Otherwise, call next_interesting_parent() to get
* the next interesting parent
*/
return next_interesting_parent(graph, parents);
}
static unsigned short graph_get_current_column_color(const struct git_graph *graph)
{
if (!want_color(graph->revs->diffopt.use_color))
return column_colors_max;
return graph->default_column_color;
}
/*
* Update the graph's default column color.
*/
static void graph_increment_column_color(struct git_graph *graph)
{
graph->default_column_color = (graph->default_column_color + 1) %
column_colors_max;
}
static unsigned short graph_find_commit_color(const struct git_graph *graph,
const struct commit *commit)
{
int i;
for (i = 0; i < graph->num_columns; i++) {
if (graph->columns[i].commit == commit)
return graph->columns[i].color;
}
return graph_get_current_column_color(graph);
}
static int graph_find_new_column_by_commit(struct git_graph *graph,
struct commit *commit)
{
int i;
for (i = 0; i < graph->num_new_columns; i++) {
if (graph->new_columns[i].commit == commit)
return i;
}
return -1;
}
static void graph_insert_into_new_columns(struct git_graph *graph,
struct commit *commit,
int idx)
{
int i = graph_find_new_column_by_commit(graph, commit);
int mapping_idx;
/*
* If the commit is not already in the new_columns array, then add it
* and record it as being in the final column.
*/
if (i < 0) {
i = graph->num_new_columns++;
graph->new_columns[i].commit = commit;
graph->new_columns[i].color = graph_find_commit_color(graph, commit);
}
if (graph->num_parents > 1 && idx > -1 && graph->merge_layout == -1) {
/*
* If this is the first parent of a merge, choose a layout for
* the merge line based on whether the parent appears in a
* column to the left of the merge
*/
int dist, shift;
dist = idx - i;
shift = (dist > 1) ? 2 * dist - 3 : 1;
graph->merge_layout = (dist > 0) ? 0 : 1;
graph->edges_added = graph->num_parents + graph->merge_layout - 2;
mapping_idx = graph->width + (graph->merge_layout - 1) * shift;
graph->width += 2 * graph->merge_layout;
} else if (graph->edges_added > 0 && i == graph->mapping[graph->width - 2]) {
/*
* If some columns have been added by a merge, but this commit
* was found in the last existing column, then adjust the
* numbers so that the two edges immediately join, i.e.:
*
* * | * |
* |\ \ => |\|
* | |/ | *
* | *
*/
mapping_idx = graph->width - 2;
graph->edges_added = -1;
} else {
mapping_idx = graph->width;
graph->width += 2;
}
graph->mapping[mapping_idx] = i;
}
static void graph_update_columns(struct git_graph *graph)
{
struct commit_list *parent;
int max_new_columns;
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.
*/
SWAP(graph->columns, graph->new_columns);
graph->num_columns = graph->num_new_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;
graph->width = 0;
graph->prev_edges_added = graph->edges_added;
graph->edges_added = 0;
/*
* 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;
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;
graph->commit_index = i;
graph->merge_layout = -1;
for (parent = first_interesting_parent(graph);
parent;
parent = next_interesting_parent(graph, parent)) {
/*
* If this is a merge, or the start of a new
* childless column, increment the current
* color.
*/
if (graph->num_parents > 1 ||
!is_commit_in_columns) {
graph_increment_column_color(graph);
}
graph_insert_into_new_columns(graph, parent->item, i);
}
/*
* We always need to increment graph->width by at
* least 2, even if it has no interesting parents.
* The current commit always takes up at least 2
* spaces.
*/
if (graph->num_parents == 0)
graph->width += 2;
} else {
graph_insert_into_new_columns(graph, col_commit, -1);
}
}
/*
* Shrink mapping_size to be the minimum necessary
*/
while (graph->mapping_size > 1 &&
graph->mapping[graph->mapping_size - 1] < 0)
graph->mapping_size--;
}
static int graph_num_dashed_parents(struct git_graph *graph)
{
return graph->num_parents + graph->merge_layout - 3;
}
static int graph_num_expansion_rows(struct git_graph *graph)
{
/*
* Normally, we need two expansion rows for each dashed parent line from
* an octopus merge:
*
* | *
* | |\
* | | \
* | | \
* | *-. \
* | |\ \ \
*
* If the merge is skewed to the left, then its parents occupy one less
* column, and we don't need as many expansion rows to route around it;
* in some cases that means we don't need any expansion rows at all:
*
* | *
* | |\
* | * \
* |/|\ \
*/
return graph_num_dashed_parents(graph) * 2;
}
static int graph_needs_pre_commit_line(struct git_graph *graph)
{
return graph->num_parents >= 3 &&
graph->commit_index < (graph->num_columns - 1) &&
graph->expansion_row < graph_num_expansion_rows(graph);
}
void graph_update(struct git_graph *graph, struct commit *commit)
{
struct commit_list *parent;
/*
* Set the new commit
*/
graph->commit = commit;
/*
* Count how many interesting parents this commit has
*/
graph->num_parents = 0;
for (parent = first_interesting_parent(graph);
parent;
parent = next_interesting_parent(graph, parent))
{
graph->num_parents++;
}
/*
* Store the old commit_index in prev_commit_index.
* graph_update_columns() will update graph->commit_index for this
* commit.
*/
graph->prev_commit_index = graph->commit_index;
/*
* Call graph_update_columns() to update
* columns, new_columns, and mapping.
*/
graph_update_columns(graph);
graph->expansion_row = 0;
/*
* Update graph->state.
* Note that we don't call graph_update_state() here, since
* we don't want to update graph->prev_state. No line for
* graph->state was ever printed.
*
* 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.
*
* If there are 3 or more parents, we may need to print extra rows
* before the commit, to expand the branch lines around it and make
* room for it. We need to do this only if there is a branch row
* (or more) to the right of this commit.
*
* 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_needs_pre_commit_line(graph))
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 graph_line *line)
{
/*
* 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.
*/
if (line->width < graph->width)
graph_line_addchars(line, ' ', graph->width - line->width);
}
static void graph_output_padding_line(struct git_graph *graph,
struct graph_line *line)
{
int i;
/*
* Output a padding row, that leaves all branch lines unchanged
*/
for (i = 0; i < graph->num_new_columns; i++) {
graph_line_write_column(line, &graph->new_columns[i], '|');
graph_line_addch(line, ' ');
}
}
int graph_width(struct git_graph *graph)
{
return graph->width;
}
static void graph_output_skip_line(struct git_graph *graph, struct graph_line *line)
{
/*
* Output an ellipsis to indicate that a portion
* of the graph is missing.
*/
graph_line_addstr(line, "...");
if (graph_needs_pre_commit_line(graph))
graph_update_state(graph, GRAPH_PRE_COMMIT);
else
graph_update_state(graph, GRAPH_COMMIT);
}
static void graph_output_pre_commit_line(struct git_graph *graph,
struct graph_line *line)
{
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);
/*
* 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 < graph_num_expansion_rows(graph));
/*
* 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;
graph_line_write_column(line, col, '|');
graph_line_addchars(line, ' ', 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)
graph_line_write_column(line, col, '\\');
else
graph_line_write_column(line, col, '|');
} else if (seen_this && (graph->expansion_row > 0)) {
graph_line_write_column(line, col, '\\');
} else {
graph_line_write_column(line, col, '|');
}
graph_line_addch(line, ' ');
}
/*
* Increment graph->expansion_row,
* and move to state GRAPH_COMMIT if necessary
*/
graph->expansion_row++;
if (!graph_needs_pre_commit_line(graph))
graph_update_state(graph, GRAPH_COMMIT);
}
static void graph_output_commit_char(struct git_graph *graph, struct graph_line *line)
{
/*
* For boundary commits, print 'o'
* (We should only see boundary commits when revs->boundary is set.)
*/
if (graph->commit->object.flags & BOUNDARY) {
assert(graph->revs->boundary);
graph_line_addch(line, 'o');
return;
}
/*
* get_revision_mark() handles all other cases without assert()
*/
graph_line_addstr(line, get_revision_mark(graph->revs, graph->commit));
}
/*
* Draw the horizontal dashes of an octopus merge.
*/
static void graph_draw_octopus_merge(struct git_graph *graph, struct graph_line *line)
{
/*
* The parents of a merge commit can be arbitrarily reordered as they
* are mapped onto display columns, for example this is a valid merge:
*
* | | *---.
* | | |\ \ \
* | | |/ / /
* | |/| | /
* | |_|_|/
* |/| | |
* 3 1 0 2
*
* The numbers denote which parent of the merge each visual column
* corresponds to; we can't assume that the parents will initially
* display in the order given by new_columns.
*
* To find the right color for each dash, we need to consult the
* mapping array, starting from the column 2 places to the right of the
* merge commit, and use that to find out which logical column each
* edge will collapse to.
*
* Commits are rendered once all edges have collapsed to their correct
* logcial column, so commit_index gives us the right visual offset for
* the merge commit.
*/
int i, j;
struct column *col;
int dashed_parents = graph_num_dashed_parents(graph);
for (i = 0; i < dashed_parents; i++) {
j = graph->mapping[(graph->commit_index + i + 2) * 2];
col = &graph->new_columns[j];
graph_line_write_column(line, col, '-');
graph_line_write_column(line, col, (i == dashed_parents - 1) ? '.' : '-');
}
return;
}
static void graph_output_commit_line(struct git_graph *graph, struct graph_line *line)
{
int seen_this = 0;
int i;
/*
* 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 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, line);
if (graph->num_parents > 2)
graph_draw_octopus_merge(graph, line);
} else if (seen_this && (graph->edges_added > 1)) {
graph_line_write_column(line, col, '\\');
} else if (seen_this && (graph->edges_added == 1)) {
/*
* This is either a right-skewed 2-way merge
* commit, or a left-skewed 3-way merge.
* There is no GRAPH_PRE_COMMIT stage for such
* 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_edges_added > 0 &&
graph->prev_commit_index < i)
graph_line_write_column(line, col, '\\');
else
graph_line_write_column(line, col, '|');
} else if (graph->prev_state == GRAPH_COLLAPSING &&
graph->old_mapping[2 * i + 1] == i &&
graph->mapping[2 * i] < i) {
graph_line_write_column(line, col, '/');
} else {
graph_line_write_column(line, col, '|');
}
graph_line_addch(line, ' ');
}
/*
* 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 const char merge_chars[] = {'/', '|', '\\'};
static void graph_output_post_merge_line(struct git_graph *graph, struct graph_line *line)
{
int seen_this = 0;
int i, j;
struct commit_list *first_parent = first_interesting_parent(graph);
struct column *parent_col = NULL;
/*
* Output the post-merge row
*/
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 = first_parent;
int par_column;
int idx = graph->merge_layout;
char c;
seen_this = 1;
for (j = 0; j < graph->num_parents; j++) {
par_column = graph_find_new_column_by_commit(graph, parents->item);
assert(par_column >= 0);
c = merge_chars[idx];
graph_line_write_column(line, &graph->new_columns[par_column], c);
if (idx == 2) {
if (graph->edges_added > 0 || j < graph->num_parents - 1)
graph_line_addch(line, ' ');
} else {
idx++;
}
parents = next_interesting_parent(graph, parents);
}
if (graph->edges_added == 0)
graph_line_addch(line, ' ');
} else if (seen_this) {
if (graph->edges_added > 0)
graph_line_write_column(line, col, '\\');
else
graph_line_write_column(line, col, '|');
graph_line_addch(line, ' ');
} else {
graph_line_write_column(line, col, '|');
if (graph->merge_layout != 0 || i != graph->commit_index - 1) {
if (parent_col)
graph_line_write_column(
line, parent_col, '_');
else
graph_line_addch(line, ' ');
}
}
if (col_commit == first_parent->item)
parent_col = col;
}
/*
* 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_collapsing_line(struct git_graph *graph, struct graph_line *line)
{
int i;
short used_horizontal = 0;
int horizontal_edge = -1;
int horizontal_edge_target = -1;
/*
* Swap the mapping and old_mapping arrays
*/
SWAP(graph->mapping, graph->old_mapping);
/*
* Clear out the mapping array
*/
for (i = 0; i < graph->mapping_size; i++)
graph->mapping[i] = -1;
for (i = 0; i < graph->mapping_size; i++) {
int target = graph->old_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->mapping[i] == -1);
graph->mapping[i] = target;
} else if (graph->mapping[i - 1] < 0) {
/*
* Nothing is to the left.
* Move to the left by one
*/
graph->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->mapping[j] = target;
}
} else if (graph->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 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->mapping[i - 1] > target);
assert(graph->mapping[i - 2] < 0);
graph->mapping[i - 2] = target;
/*
* Mark this branch as the horizontal edge to
* prevent any other edges from moving
* horizontally.
*/
if (horizontal_edge == -1) {
int j;
horizontal_edge_target = target;
horizontal_edge = i - 1;
for (j = (target * 2) + 3; j < (i - 2); j += 2)
graph->mapping[j] = target;
}
}
}
/*
* Copy the current mapping array into old_mapping
*/
COPY_ARRAY(graph->old_mapping, graph->mapping, graph->mapping_size);
/*
* The new mapping may be 1 smaller than the old mapping
*/
if (graph->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->mapping[i];
if (target < 0)
graph_line_addch(line, ' ');
else if (target * 2 == i)
graph_line_write_column(line, &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->mapping[i] = -1;
used_horizontal = 1;
graph_line_write_column(line, &graph->new_columns[target], '_');
} else {
if (used_horizontal && i < horizontal_edge)
graph->mapping[i] = -1;
graph_line_write_column(line, &graph->new_columns[target], '/');
}
}
/*
* 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);
}
int graph_next_line(struct git_graph *graph, struct strbuf *sb)
{
int shown_commit_line = 0;
struct graph_line line = { .buf = sb, .width = 0 };
/*
* 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 -1;
switch (graph->state) {
case GRAPH_PADDING:
graph_output_padding_line(graph, &line);
break;
case GRAPH_SKIP:
graph_output_skip_line(graph, &line);
break;
case GRAPH_PRE_COMMIT:
graph_output_pre_commit_line(graph, &line);
break;
case GRAPH_COMMIT:
graph_output_commit_line(graph, &line);
shown_commit_line = 1;
break;
case GRAPH_POST_MERGE:
graph_output_post_merge_line(graph, &line);
break;
case GRAPH_COLLAPSING:
graph_output_collapsing_line(graph, &line);
break;
}
graph_pad_horizontally(graph, &line);
return shown_commit_line;
}
static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
{
int i;
struct graph_line line = { .buf = sb, .width = 0 };
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];
graph_line_write_column(&line, col, '|');
if (col->commit == graph->commit && graph->num_parents > 2) {
int len = (graph->num_parents - 2) * 2;
graph_line_addchars(&line, ' ', len);
} else {
graph_line_addch(&line, ' ');
}
}
graph_pad_horizontally(graph, &line);
/*
* Update graph->prev_state since we have output a padding line
*/
graph->prev_state = GRAPH_PADDING;
}
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 = STRBUF_INIT;
int shown_commit_line = 0;
graph_show_line_prefix(default_diffopt);
if (!graph)
return;
/*
* When showing a diff of a merge against each of its parents, we
* are called once for each parent without graph_update having been
* called. In this case, simply output a single padding line.
*/
if (graph_is_commit_finished(graph)) {
graph_show_padding(graph);
shown_commit_line = 1;
}
while (!shown_commit_line && !graph_is_commit_finished(graph)) {
shown_commit_line = graph_next_line(graph, &msgbuf);
fwrite(msgbuf.buf, sizeof(char), msgbuf.len,
graph->revs->diffopt.file);
if (!shown_commit_line) {
putc('\n', graph->revs->diffopt.file);
graph_show_line_prefix(&graph->revs->diffopt);
}
strbuf_setlen(&msgbuf, 0);
}
strbuf_release(&msgbuf);
}
void graph_show_oneline(struct git_graph *graph)
{
struct strbuf msgbuf = STRBUF_INIT;
graph_show_line_prefix(default_diffopt);
if (!graph)
return;
graph_next_line(graph, &msgbuf);
fwrite(msgbuf.buf, sizeof(char), msgbuf.len, graph->revs->diffopt.file);
strbuf_release(&msgbuf);
}
void graph_show_padding(struct git_graph *graph)
{
struct strbuf msgbuf = STRBUF_INIT;
graph_show_line_prefix(default_diffopt);
if (!graph)
return;
graph_padding_line(graph, &msgbuf);
fwrite(msgbuf.buf, sizeof(char), msgbuf.len, graph->revs->diffopt.file);
strbuf_release(&msgbuf);
}
int graph_show_remainder(struct git_graph *graph)
{
struct strbuf msgbuf = STRBUF_INIT;
int shown = 0;
graph_show_line_prefix(default_diffopt);
if (!graph)
return 0;
if (graph_is_commit_finished(graph))
return 0;
for (;;) {
graph_next_line(graph, &msgbuf);
fwrite(msgbuf.buf, sizeof(char), msgbuf.len,
graph->revs->diffopt.file);
strbuf_setlen(&msgbuf, 0);
shown = 1;
if (!graph_is_commit_finished(graph)) {
putc('\n', graph->revs->diffopt.file);
graph_show_line_prefix(&graph->revs->diffopt);
} else {
break;
}
}
strbuf_release(&msgbuf);
return shown;
}
static void graph_show_strbuf(struct git_graph *graph,
FILE *file,
struct strbuf const *sb)
{
char *p;
/*
* 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, file);
if (next_p && *next_p != '\0')
graph_show_oneline(graph);
p = next_p;
}
}
void graph_show_commit_msg(struct git_graph *graph,
FILE *file,
struct strbuf const *sb)
{
int newline_terminated;
/*
* Show the commit message
*/
graph_show_strbuf(graph, file, sb);
if (!graph)
return;
newline_terminated = (sb->len && sb->buf[sb->len - 1] == '\n');
/*
* 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)
putc('\n', file);
graph_show_remainder(graph);
/*
* If sb ends with a newline, our output should too.
*/
if (newline_terminated)
putc('\n', file);
}
}