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-rw-r--r--third_party/git/graph.c1430
1 files changed, 0 insertions, 1430 deletions
diff --git a/third_party/git/graph.c b/third_party/git/graph.c
deleted file mode 100644
index f53135485f..0000000000
--- a/third_party/git/graph.c
+++ /dev/null
@@ -1,1430 +0,0 @@
-#include "cache.h"
-#include "config.h"
-#include "commit.h"
-#include "color.h"
-#include "graph.h"
-#include "revision.h"
-#include "argv-array.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.
- */
-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 argv_array *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))
-			argv_array_push(colors, color);
-		else
-			warning(_("ignore invalid color '%.*s' in log.graphColors"),
-				(int)(comma - start), start);
-		start = comma + 1;
-	}
-	argv_array_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];
-}
-
-static void strbuf_write_column(struct strbuf *sb, const struct column *c,
-				char col_char)
-{
-	if (c->color < column_colors_max)
-		strbuf_addstr(sb, column_get_color_code(c->color));
-	strbuf_addch(sb, col_char);
-	if (c->color < column_colors_max)
-		strbuf_addstr(sb, column_get_color_code(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;
-	/*
-	 * 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;
-	/*
-	 * 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 argv_array custom_colors = ARGV_ARRAY_INIT;
-			argv_array_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.argv,
-						custom_colors.argc - 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->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->new_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->new_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 void graph_insert_into_new_columns(struct git_graph *graph,
-					  struct commit *commit,
-					  int *mapping_index)
-{
-	int i;
-
-	/*
-	 * 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->new_columns[graph->num_new_columns].color = graph_find_commit_color(graph, 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 to be printed, it
-	 * still takes up a column for itself.
-	 */
-	if (graph->num_parents < 1)
-		max_cols++;
-
-	/*
-	 * We added a column for 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;
-	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.
-	 */
-	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;
-
-	/*
-	 * 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) {
-			int old_mapping_idx = mapping_idx;
-			seen_this = 1;
-			graph->commit_index = i;
-			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,
-							      &mapping_idx);
-			}
-			/*
-			 * We always need to increment mapping_idx by at
-			 * least 2, even if it has no interesting parents.
-			 * The current commit always takes up at least 2
-			 * spaces.
-			 */
-			if (mapping_idx == old_mapping_idx)
-				mapping_idx += 2;
-		} 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 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->num_parents >= 3 &&
-		 graph->commit_index < (graph->num_columns - 1))
-		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,
-				   int chars_written)
-{
-	/*
-	 * 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 (chars_written < graph->width)
-		strbuf_addchars(sb, ' ', graph->width - chars_written);
-}
-
-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);
-}
-
-
-int graph_width(struct git_graph *graph)
-{
-	return graph->width;
-}
-
-
-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, 3);
-
-	if (graph->num_parents >= 3 &&
-	    graph->commit_index < (graph->num_columns - 1))
-		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 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_addchars(sb, ' ', 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);
-}
-
-static void graph_output_commit_char(struct git_graph *graph, struct strbuf *sb)
-{
-	/*
-	 * 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);
-		strbuf_addch(sb, 'o');
-		return;
-	}
-
-	/*
-	 * get_revision_mark() handles all other cases without assert()
-	 */
-	strbuf_addstr(sb, get_revision_mark(graph->revs, graph->commit));
-}
-
-/*
- * Draw the horizontal dashes of 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_parents represents the number of parents which don't
-	 * need to have dashes (the edges labeled "0" and "1").  And
-	 * dashful_parents are the remaining ones.
-	 *
-	 * | *---.
-	 * | |\ \ \
-	 * | | | | |
-	 * x 0 1 2 3
-	 *
-	 */
-	const int dashless_parents = 2;
-	int dashful_parents = graph->num_parents - dashless_parents;
-
-	/*
-	 * Usually, we add one new column for each parent (like the diagram
-	 * above) but sometimes the first parent goes into an existing column,
-	 * like this:
-	 *
-	 * | *---.
-	 * | |\ \ \
-	 * |/ / / /
-	 * x 0 1 2
-	 *
-	 * In which case the number of parents will be one greater than the
-	 * number of added columns.
-	 */
-	int added_cols = (graph->num_new_columns - graph->num_columns);
-	int parent_in_old_cols = graph->num_parents - added_cols;
-
-	/*
-	 * In both cases, commit_index corresponds to the edge labeled "0".
-	 */
-	int first_col = graph->commit_index + dashless_parents
-	    - parent_in_old_cols;
-
-	int i;
-	for (i = 0; i < dashful_parents; i++) {
-		strbuf_write_column(sb, &graph->new_columns[i+first_col], '-');
-		strbuf_write_column(sb, &graph->new_columns[i+first_col],
-				    i == dashful_parents-1 ? '.' : '-');
-	}
-	return 2 * dashful_parents;
-}
-
-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 struct column *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 &graph->new_columns[i];
-	}
-	return NULL;
-}
-
-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_collapsing_line(struct git_graph *graph, struct strbuf *sb)
-{
-	int i;
-	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
-	 */
-	SWAP(graph->mapping, graph->new_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);
-}
-
-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;
-}
-
-static void graph_padding_line(struct git_graph *graph, struct strbuf *sb)
-{
-	int i;
-	int chars_written = 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];
-
-		strbuf_write_column(sb, col, '|');
-		chars_written++;
-
-		if (col->commit == graph->commit && graph->num_parents > 2) {
-			int len = (graph->num_parents - 2) * 2;
-			strbuf_addchars(sb, ' ', len);
-			chars_written += len;
-		} else {
-			strbuf_addch(sb, ' ');
-			chars_written++;
-		}
-	}
-
-	graph_pad_horizontally(graph, sb, chars_written);
-
-	/*
-	 * 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);
-	}
-}