git/graph.h
Jacob Keller 660e113ce1 graph: add support for --line-prefix on all graph-aware output
Add an extension to git-diff and git-log (and any other graph-aware
displayable output) such that "--line-prefix=<string>" will print the
additional line-prefix on every line of output.

To make this work, we have to fix a few bugs in the graph API that force
graph_show_commit_msg to be used only when you have a valid graph.
Additionally, we extend the default_diff_output_prefix handler to work
even when no graph is enabled.

This is somewhat of a hack on top of the graph API, but I think it
should be acceptable here.

This will be used by a future extension of submodule display which
displays the submodule diff as the actual diff between the pre and post
commit in the submodule project.

Add some tests for both git-log and git-diff to ensure that the prefix
is honored correctly.

Signed-off-by: Jacob Keller <jacob.keller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-31 18:07:09 -07:00

140 lines
4.9 KiB
C

#ifndef GRAPH_H
#define GRAPH_H
#include "diff.h"
/* A graph is a pointer to this opaque structure */
struct git_graph;
/*
* Called to setup global display of line_prefix diff option.
*
* Passed a diff_options structure which indicates the line_prefix and the
* file to output the prefix to. This is sort of a hack used so that the
* line_prefix will be honored by all flows which also honor "--graph"
* regardless of whether a graph has actually been setup. The normal graph
* flow will honor the exact diff_options passed, but a NULL graph will cause
* display of a line_prefix to stdout.
*/
void graph_setup_line_prefix(struct diff_options *diffopt);
/*
* 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);
/*
* Return current width of the graph in on-screen characters.
*/
int graph_width(struct git_graph *graph);
/*
* 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.
*
* 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_commit_msg can be called even with a NULL graph.
*/
void graph_show_commit_msg(struct git_graph *graph,
FILE *file,
struct strbuf const *sb);
#endif /* GRAPH_H */