ui-log: Implement support for commit graphs

Teach CGit to print an ASCII art commit graph to the left of the commit
message, similar to 'git log --graph'. The graph adds extra lines (table
rows) to the log when needed to add/remove/shuffle edges in the graph.

When 'showmsg' is enabled, the graph is automatically padded to account
for the extra lines added by the commit message/notes.

This feature is controlled by a new config variable: "enable-commit-graph"
(disabled by default), and individual repos can control it by setting
"repo.enable-commit-graph".

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/cgit.c b/cgit.c
index 412fbf0..53ab68d 100644
--- a/cgit.c
+++ b/cgit.c
@@ -1,239 +1,243 @@
 /* cgit.c: cgi for the git scm
  *
  * Copyright (C) 2006 Lars Hjemli
  * Copyright (C) 2010 Jason A. Donenfeld <Jason@zx2c4.com>
  *
  * Licensed under GNU General Public License v2
  *   (see COPYING for full license text)
  */
 
 #include "cgit.h"
 #include "cache.h"
 #include "cmd.h"
 #include "configfile.h"
 #include "html.h"
 #include "ui-shared.h"
 #include "ui-stats.h"
 #include "scan-tree.h"
 
 const char *cgit_version = CGIT_VERSION;
 
 void add_mimetype(const char *name, const char *value)
 {
 	struct string_list_item *item;
 
 	item = string_list_insert(&ctx.cfg.mimetypes, xstrdup(name));
 	item->util = xstrdup(value);
 }
 
 struct cgit_filter *new_filter(const char *cmd, int extra_args)
 {
 	struct cgit_filter *f;
 
 	if (!cmd || !cmd[0])
 		return NULL;
 
 	f = xmalloc(sizeof(struct cgit_filter));
 	f->cmd = xstrdup(cmd);
 	f->argv = xmalloc((2 + extra_args) * sizeof(char *));
 	f->argv[0] = f->cmd;
 	f->argv[1] = NULL;
 	return f;
 }
 
 static void process_cached_repolist(const char *path);
 
 void repo_config(struct cgit_repo *repo, const char *name, const char *value)
 {
 	if (!strcmp(name, "name"))
 		repo->name = xstrdup(value);
 	else if (!strcmp(name, "clone-url"))
 		repo->clone_url = xstrdup(value);
 	else if (!strcmp(name, "desc"))
 		repo->desc = xstrdup(value);
 	else if (!strcmp(name, "owner"))
 		repo->owner = xstrdup(value);
 	else if (!strcmp(name, "defbranch"))
 		repo->defbranch = xstrdup(value);
 	else if (!strcmp(name, "snapshots"))
 		repo->snapshots = ctx.cfg.snapshots & cgit_parse_snapshots_mask(value);
+	else if (!strcmp(name, "enable-commit-graph"))
+		repo->enable_commit_graph = ctx.cfg.enable_commit_graph * atoi(value);
 	else if (!strcmp(name, "enable-log-filecount"))
 		repo->enable_log_filecount = ctx.cfg.enable_log_filecount * atoi(value);
 	else if (!strcmp(name, "enable-log-linecount"))
 		repo->enable_log_linecount = ctx.cfg.enable_log_linecount * atoi(value);
 	else if (!strcmp(name, "enable-remote-branches"))
 		repo->enable_remote_branches = atoi(value);
 	else if (!strcmp(name, "enable-subject-links"))
 		repo->enable_subject_links = atoi(value);
 	else if (!strcmp(name, "max-stats"))
 		repo->max_stats = cgit_find_stats_period(value, NULL);
 	else if (!strcmp(name, "module-link"))
 		repo->module_link= xstrdup(value);
 	else if (!strcmp(name, "section"))
 		repo->section = xstrdup(value);
 	else if (!strcmp(name, "readme") && value != NULL) {
 		repo->readme = xstrdup(value);
 	} else if (ctx.cfg.enable_filter_overrides) {
 		if (!strcmp(name, "about-filter"))
 			repo->about_filter = new_filter(value, 0);
 		else if (!strcmp(name, "commit-filter"))
 			repo->commit_filter = new_filter(value, 0);
 		else if (!strcmp(name, "source-filter"))
 			repo->source_filter = new_filter(value, 1);
 	}
 }
 
 void config_cb(const char *name, const char *value)
 {
 	if (!strcmp(name, "section") || !strcmp(name, "repo.group"))
 		ctx.cfg.section = xstrdup(value);
 	else if (!strcmp(name, "repo.url"))
 		ctx.repo = cgit_add_repo(value);
 	else if (ctx.repo && !strcmp(name, "repo.path"))
 		ctx.repo->path = trim_end(value, '/');
 	else if (ctx.repo && !prefixcmp(name, "repo."))
 		repo_config(ctx.repo, name + 5, value);
 	else if (!strcmp(name, "readme"))
 		ctx.cfg.readme = xstrdup(value);
 	else if (!strcmp(name, "root-title"))
 		ctx.cfg.root_title = xstrdup(value);
 	else if (!strcmp(name, "root-desc"))
 		ctx.cfg.root_desc = xstrdup(value);
 	else if (!strcmp(name, "root-readme"))
 		ctx.cfg.root_readme = xstrdup(value);
 	else if (!strcmp(name, "css"))
 		ctx.cfg.css = xstrdup(value);
 	else if (!strcmp(name, "favicon"))
 		ctx.cfg.favicon = xstrdup(value);
 	else if (!strcmp(name, "footer"))
 		ctx.cfg.footer = xstrdup(value);
 	else if (!strcmp(name, "head-include"))
 		ctx.cfg.head_include = xstrdup(value);
 	else if (!strcmp(name, "header"))
 		ctx.cfg.header = xstrdup(value);
 	else if (!strcmp(name, "logo"))
 		ctx.cfg.logo = xstrdup(value);
 	else if (!strcmp(name, "index-header"))
 		ctx.cfg.index_header = xstrdup(value);
 	else if (!strcmp(name, "index-info"))
 		ctx.cfg.index_info = xstrdup(value);
 	else if (!strcmp(name, "logo-link"))
 		ctx.cfg.logo_link = xstrdup(value);
 	else if (!strcmp(name, "module-link"))
 		ctx.cfg.module_link = xstrdup(value);
 	else if (!strcmp(name, "strict-export"))
 		ctx.cfg.strict_export = xstrdup(value);
 	else if (!strcmp(name, "virtual-root")) {
 		ctx.cfg.virtual_root = trim_end(value, '/');
 		if (!ctx.cfg.virtual_root && (!strcmp(value, "/")))
 			ctx.cfg.virtual_root = "";
 	} else if (!strcmp(name, "nocache"))
 		ctx.cfg.nocache = atoi(value);
 	else if (!strcmp(name, "noplainemail"))
 		ctx.cfg.noplainemail = atoi(value);
 	else if (!strcmp(name, "noheader"))
 		ctx.cfg.noheader = atoi(value);
 	else if (!strcmp(name, "snapshots"))
 		ctx.cfg.snapshots = cgit_parse_snapshots_mask(value);
 	else if (!strcmp(name, "enable-filter-overrides"))
 		ctx.cfg.enable_filter_overrides = atoi(value);
 	else if (!strcmp(name, "enable-gitweb-owner"))
 		ctx.cfg.enable_gitweb_owner = atoi(value);
 	else if (!strcmp(name, "enable-index-links"))
 		ctx.cfg.enable_index_links = atoi(value);
+	else if (!strcmp(name, "enable-commit-graph"))
+		ctx.cfg.enable_commit_graph = atoi(value);
 	else if (!strcmp(name, "enable-log-filecount"))
 		ctx.cfg.enable_log_filecount = atoi(value);
 	else if (!strcmp(name, "enable-log-linecount"))
 		ctx.cfg.enable_log_linecount = atoi(value);
 	else if (!strcmp(name, "enable-remote-branches"))
 		ctx.cfg.enable_remote_branches = atoi(value);
 	else if (!strcmp(name, "enable-subject-links"))
 		ctx.cfg.enable_subject_links = atoi(value);
 	else if (!strcmp(name, "enable-tree-linenumbers"))
 		ctx.cfg.enable_tree_linenumbers = atoi(value);
 	else if (!strcmp(name, "max-stats"))
 		ctx.cfg.max_stats = cgit_find_stats_period(value, NULL);
 	else if (!strcmp(name, "cache-size"))
 		ctx.cfg.cache_size = atoi(value);
 	else if (!strcmp(name, "cache-root"))
 		ctx.cfg.cache_root = xstrdup(expand_macros(value));
 	else if (!strcmp(name, "cache-root-ttl"))
 		ctx.cfg.cache_root_ttl = atoi(value);
 	else if (!strcmp(name, "cache-repo-ttl"))
 		ctx.cfg.cache_repo_ttl = atoi(value);
 	else if (!strcmp(name, "cache-scanrc-ttl"))
 		ctx.cfg.cache_scanrc_ttl = atoi(value);
 	else if (!strcmp(name, "cache-static-ttl"))
 		ctx.cfg.cache_static_ttl = atoi(value);
 	else if (!strcmp(name, "cache-dynamic-ttl"))
 		ctx.cfg.cache_dynamic_ttl = atoi(value);
 	else if (!strcmp(name, "about-filter"))
 		ctx.cfg.about_filter = new_filter(value, 0);
 	else if (!strcmp(name, "commit-filter"))
 		ctx.cfg.commit_filter = new_filter(value, 0);
 	else if (!strcmp(name, "embedded"))
 		ctx.cfg.embedded = atoi(value);
 	else if (!strcmp(name, "max-atom-items"))
 		ctx.cfg.max_atom_items = atoi(value);
 	else if (!strcmp(name, "max-message-length"))
 		ctx.cfg.max_msg_len = atoi(value);
 	else if (!strcmp(name, "max-repodesc-length"))
 		ctx.cfg.max_repodesc_len = atoi(value);
 	else if (!strcmp(name, "max-blob-size"))
 		ctx.cfg.max_blob_size = atoi(value);
 	else if (!strcmp(name, "max-repo-count"))
 		ctx.cfg.max_repo_count = atoi(value);
 	else if (!strcmp(name, "max-commit-count"))
 		ctx.cfg.max_commit_count = atoi(value);
 	else if (!strcmp(name, "project-list"))
 		ctx.cfg.project_list = xstrdup(expand_macros(value));
 	else if (!strcmp(name, "scan-path"))
 		if (!ctx.cfg.nocache && ctx.cfg.cache_size)
 			process_cached_repolist(expand_macros(value));
 		else if (ctx.cfg.project_list)
 			scan_projects(expand_macros(value),
 				      ctx.cfg.project_list, repo_config);
 		else
 			scan_tree(expand_macros(value), repo_config);
 	else if (!strcmp(name, "section-from-path"))
 		ctx.cfg.section_from_path = atoi(value);
 	else if (!strcmp(name, "source-filter"))
 		ctx.cfg.source_filter = new_filter(value, 1);
 	else if (!strcmp(name, "summary-log"))
 		ctx.cfg.summary_log = atoi(value);
 	else if (!strcmp(name, "summary-branches"))
 		ctx.cfg.summary_branches = atoi(value);
 	else if (!strcmp(name, "summary-tags"))
 		ctx.cfg.summary_tags = atoi(value);
 	else if (!strcmp(name, "side-by-side-diffs"))
 		ctx.cfg.ssdiff = atoi(value);
 	else if (!strcmp(name, "agefile"))
 		ctx.cfg.agefile = xstrdup(value);
 	else if (!strcmp(name, "renamelimit"))
 		ctx.cfg.renamelimit = atoi(value);
 	else if (!strcmp(name, "remove-suffix"))
 		ctx.cfg.remove_suffix = atoi(value);
 	else if (!strcmp(name, "robots"))
 		ctx.cfg.robots = xstrdup(value);
 	else if (!strcmp(name, "clone-prefix"))
 		ctx.cfg.clone_prefix = xstrdup(value);
 	else if (!strcmp(name, "local-time"))
 		ctx.cfg.local_time = atoi(value);
 	else if (!prefixcmp(name, "mimetype."))
 		add_mimetype(name + 9, value);
 	else if (!strcmp(name, "include"))
 		parse_configfile(expand_macros(value), config_cb);
 }
 
 static void querystring_cb(const char *name, const char *value)
 {
 	if (!value)
 		value = "";
 
 	if (!strcmp(name,"r")) {
 		ctx.qry.repo = xstrdup(value);
 		ctx.repo = cgit_get_repoinfo(value);
 	} else if (!strcmp(name, "p")) {
 		ctx.qry.page = xstrdup(value);
 	} else if (!strcmp(name, "url")) {
 		if (*value == '/')
@@ -447,192 +451,194 @@ static void process_request(void *cbdata)
 		ctx->page.title = "cgit error";
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 		cgit_print_error("Invalid request");
 		cgit_print_docend();
 		return;
 	}
 
 	/* If cmd->want_vpath is set, assume ctx->qry.path contains a "virtual"
 	 * in-project path limit to be made available at ctx->qry.vpath.
 	 * Otherwise, no path limit is in effect (ctx->qry.vpath = NULL).
 	 */
 	ctx->qry.vpath = cmd->want_vpath ? ctx->qry.path : NULL;
 
 	if (cmd->want_repo && !ctx->repo) {
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 		cgit_print_error(fmt("No repository selected"));
 		cgit_print_docend();
 		return;
 	}
 
 	if (ctx->repo && prepare_repo_cmd(ctx))
 		return;
 
 	if (cmd->want_layout) {
 		cgit_print_http_headers(ctx);
 		cgit_print_docstart(ctx);
 		cgit_print_pageheader(ctx);
 	}
 
 	cmd->fn(ctx);
 
 	if (cmd->want_layout)
 		cgit_print_docend();
 }
 
 int cmp_repos(const void *a, const void *b)
 {
 	const struct cgit_repo *ra = a, *rb = b;
 	return strcmp(ra->url, rb->url);
 }
 
 char *build_snapshot_setting(int bitmap)
 {
 	const struct cgit_snapshot_format *f;
 	char *result = xstrdup("");
 	char *tmp;
 	int len;
 
 	for (f = cgit_snapshot_formats; f->suffix; f++) {
 		if (f->bit & bitmap) {
 			tmp = result;
 			result = xstrdup(fmt("%s%s ", tmp, f->suffix));
 			free(tmp);
 		}
 	}
 	len = strlen(result);
 	if (len)
 		result[len - 1] = '\0';
 	return result;
 }
 
 char *get_first_line(char *txt)
 {
 	char *t = xstrdup(txt);
 	char *p = strchr(t, '\n');
 	if (p)
 		*p = '\0';
 	return t;
 }
 
 void print_repo(FILE *f, struct cgit_repo *repo)
 {
 	fprintf(f, "repo.url=%s\n", repo->url);
 	fprintf(f, "repo.name=%s\n", repo->name);
 	fprintf(f, "repo.path=%s\n", repo->path);
 	if (repo->owner)
 		fprintf(f, "repo.owner=%s\n", repo->owner);
 	if (repo->desc) {
 		char *tmp = get_first_line(repo->desc);
 		fprintf(f, "repo.desc=%s\n", tmp);
 		free(tmp);
 	}
 	if (repo->readme)
 		fprintf(f, "repo.readme=%s\n", repo->readme);
 	if (repo->defbranch)
 		fprintf(f, "repo.defbranch=%s\n", repo->defbranch);
 	if (repo->module_link)
 		fprintf(f, "repo.module-link=%s\n", repo->module_link);
 	if (repo->section)
 		fprintf(f, "repo.section=%s\n", repo->section);
 	if (repo->clone_url)
 		fprintf(f, "repo.clone-url=%s\n", repo->clone_url);
+	fprintf(f, "repo.enable-commit-graph=%d\n",
+	        repo->enable_commit_graph);
 	fprintf(f, "repo.enable-log-filecount=%d\n",
 	        repo->enable_log_filecount);
 	fprintf(f, "repo.enable-log-linecount=%d\n",
 	        repo->enable_log_linecount);
 	if (repo->about_filter && repo->about_filter != ctx.cfg.about_filter)
 		fprintf(f, "repo.about-filter=%s\n", repo->about_filter->cmd);
 	if (repo->commit_filter && repo->commit_filter != ctx.cfg.commit_filter)
 		fprintf(f, "repo.commit-filter=%s\n", repo->commit_filter->cmd);
 	if (repo->source_filter && repo->source_filter != ctx.cfg.source_filter)
 		fprintf(f, "repo.source-filter=%s\n", repo->source_filter->cmd);
 	if (repo->snapshots != ctx.cfg.snapshots) {
 		char *tmp = build_snapshot_setting(repo->snapshots);
 		fprintf(f, "repo.snapshots=%s\n", tmp);
 		free(tmp);
 	}
 	if (repo->max_stats != ctx.cfg.max_stats)
 		fprintf(f, "repo.max-stats=%s\n",
 		        cgit_find_stats_periodname(repo->max_stats));
 	fprintf(f, "\n");
 }
 
 void print_repolist(FILE *f, struct cgit_repolist *list, int start)
 {
 	int i;
 
 	for(i = start; i < list->count; i++)
 		print_repo(f, &list->repos[i]);
 }
 
 /* Scan 'path' for git repositories, save the resulting repolist in 'cached_rc'
  * and return 0 on success.
  */
 static int generate_cached_repolist(const char *path, const char *cached_rc)
 {
 	char *locked_rc;
 	int idx;
 	FILE *f;
 
 	locked_rc = xstrdup(fmt("%s.lock", cached_rc));
 	f = fopen(locked_rc, "wx");
 	if (!f) {
 		/* Inform about the error unless the lockfile already existed,
 		 * since that only means we've got concurrent requests.
 		 */
 		if (errno != EEXIST)
 			fprintf(stderr, "[cgit] Error opening %s: %s (%d)\n",
 				locked_rc, strerror(errno), errno);
 		return errno;
 	}
 	idx = cgit_repolist.count;
 	if (ctx.cfg.project_list)
 		scan_projects(path, ctx.cfg.project_list, repo_config);
 	else
 		scan_tree(path, repo_config);
 	print_repolist(f, &cgit_repolist, idx);
 	if (rename(locked_rc, cached_rc))
 		fprintf(stderr, "[cgit] Error renaming %s to %s: %s (%d)\n",
 			locked_rc, cached_rc, strerror(errno), errno);
 	fclose(f);
 	return 0;
 }
 
 static void process_cached_repolist(const char *path)
 {
 	struct stat st;
 	char *cached_rc;
 	time_t age;
 	unsigned long hash;
 
 	hash = hash_str(path);
 	if (ctx.cfg.project_list)
 		hash += hash_str(ctx.cfg.project_list);
 	cached_rc = xstrdup(fmt("%s/rc-%8lx", ctx.cfg.cache_root, hash));
 
 	if (stat(cached_rc, &st)) {
 		/* Nothing is cached, we need to scan without forking. And
 		 * if we fail to generate a cached repolist, we need to
 		 * invoke scan_tree manually.
 		 */
 		if (generate_cached_repolist(path, cached_rc)) {
 			if (ctx.cfg.project_list)
 				scan_projects(path, ctx.cfg.project_list,
 					      repo_config);
 			else
 				scan_tree(path, repo_config);
 		}
 		return;
 	}
 
 	parse_configfile(cached_rc, config_cb);
 
 	/* If the cached configfile hasn't expired, lets exit now */
 	age = time(NULL) - st.st_mtime;
 	if (age <= (ctx.cfg.cache_scanrc_ttl * 60))
 		return;