1 files changed, 114 insertions, 0 deletions
diff --git a/graph.h b/graph.h
new file mode 100644
index 0000000000..0be62bd8b1
--- /dev/null
+++ b/graph.h
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+#ifndef GRAPH_H
+#define GRAPH_H
+
+/* A graph is a pointer to this opaque structure */
+struct git_graph;
+
+/*
+ * Set up a custom scheme for column colors.
+ *
+ * The default column color scheme inserts ANSI color escapes to colorize
+ * the graph. The various color escapes are stored in an array of strings
+ * where each entry corresponds to a color, except for the last entry,
+ * which denotes the escape for resetting the color back to the default.
+ * When generating the graph, strings from this array are inserted before
+ * and after the various column characters.
+ *
+ * This function allows you to enable a custom array of color escapes.
+ * The 'colors_max' argument is the index of the last "reset" entry.
+ *
+ * This functions must be called BEFORE graph_init() is called.
+ *
+ * NOTE: This function isn't used in Git outside graph.c but it is used
+ * by CGit (http://git.zx2c4.com/cgit/) to use HTML for colors.
+ */
+void graph_set_column_colors(const char **colors, unsigned short colors_max);
+
+/*
+ * Create a new struct git_graph.
+ */
+struct git_graph *graph_init(struct rev_info *opt);
+
+/*
+ * Update a git_graph with a new commit.
+ * This will cause the graph to begin outputting lines for the new commit
+ * the next time graph_next_line() is called.
+ *
+ * If graph_update() is called before graph_is_commit_finished() returns 1,
+ * the next call to graph_next_line() will output an ellipsis ("...")
+ * to indicate that a portion of the graph is missing.
+ */
+void graph_update(struct git_graph *graph, struct commit *commit);
+
+/*
+ * Determine if a graph has finished outputting lines for the current
+ * commit.
+ *
+ * Returns 1 if graph_next_line() needs to be called again before
+ * graph_update() should be called.  Returns 0 if no more lines are needed
+ * for this commit.  If 0 is returned, graph_next_line() may still be
+ * called without calling graph_update(), and it will merely output
+ * appropriate "vertical padding" in the graph.
+ */
+int graph_is_commit_finished(struct git_graph const *graph);
+
+/*
+ * Output the next line for a graph.
+ * This formats the next graph line into the specified strbuf.  It is not
+ * terminated with a newline.
+ *
+ * Returns 1 if the line includes the current commit, and 0 otherwise.
+ * graph_next_line() will return 1 exactly once for each time
+ * graph_update() is called.
+ *
+ * NOTE: This function isn't used in Git outside graph.c but it is used
+ * by CGit (http://git.zx2c4.com/cgit/) to wrap HTML around graph lines.
+ */
+int graph_next_line(struct git_graph *graph, struct strbuf *sb);
+
+
+/*
+ * graph_show_*: helper functions for printing to stdout
+ */
+
+
+/*
+ * If the graph is non-NULL, print the history graph to stdout,
+ * up to and including the line containing this commit.
+ * Does not print a terminating newline on the last line.
+ */
+void graph_show_commit(struct git_graph *graph);
+
+/*
+ * If the graph is non-NULL, print one line of the history graph to stdout.
+ * Does not print a terminating newline on the last line.
+ */
+void graph_show_oneline(struct git_graph *graph);
+
+/*
+ * If the graph is non-NULL, print one line of vertical graph padding to
+ * stdout.  Does not print a terminating newline on the last line.
+ */
+void graph_show_padding(struct git_graph *graph);
+
+/*
+ * If the graph is non-NULL, print the rest of the history graph for this
+ * commit to stdout.  Does not print a terminating newline on the last line.
+ */
+int graph_show_remainder(struct git_graph *graph);
+
+/*
+ * Print a commit message strbuf and the remainder of the graph to stdout.
+ *
+ * This is similar to graph_show_strbuf(), but it always prints the
+ * remainder of the graph.
+ *
+ * If the strbuf ends with a newline, the output printed by
+ * graph_show_commit_msg() will end with a newline.  If the strbuf is
+ * missing a terminating newline (including if it is empty), the output
+ * printed by graph_show_commit_msg() will also be missing a terminating
+ * newline.
+ */
+void graph_show_commit_msg(struct git_graph *graph, struct strbuf const *sb);
+
+#endif /* GRAPH_H */