cli: add a blame command

src/cli/cmd.h

@@ -25,6 +25,7 @@ extern const cli_cmd_spec cli_cmds[];
 extern const cli_cmd_spec *cli_cmd_spec_byname(const char *name);
 
 /* Commands */
+extern int cmd_blame(int argc, char **argv);
 extern int cmd_cat_file(int argc, char **argv);
 extern int cmd_clone(int argc, char **argv);
 extern int cmd_config(int argc, char **argv);

src/cli/cmd_blame.c

@@ -0,0 +1,288 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include <stdio.h>
+#include <git2.h>
+#include "common.h"
+#include "cmd.h"
+#include "error.h"
+#include "sighandler.h"
+#include "progress.h"
+
+#include "fs_path.h"
+#include "futils.h"
+#include "date.h"
+#include "hashmap.h"
+
+#define COMMAND_NAME "blame"
+
+static char *file;
+static int porcelain, line_porcelain;
+static int show_help;
+
+static const cli_opt_spec opts[] = {
+	CLI_COMMON_OPT,
+
+	{ CLI_OPT_TYPE_SWITCH,    "porcelain",      'p', &porcelain, 1,
+	  CLI_OPT_USAGE_DEFAULT,   NULL,            "show machine readable output" },
+	{ CLI_OPT_TYPE_SWITCH,    "line-porcelain",  0,  &line_porcelain, 1,
+	  CLI_OPT_USAGE_DEFAULT,   NULL,            "show individual lines in machine readable output" },
+	{ CLI_OPT_TYPE_LITERAL },
+	{ CLI_OPT_TYPE_ARG,       "file",            0,  &file, 0,
+	  CLI_OPT_USAGE_REQUIRED, "file",           "file to blame" },
+
+	{ 0 }
+};
+
+static void print_help(void)
+{
+	cli_opt_usage_fprint(stdout, PROGRAM_NAME, COMMAND_NAME, opts);
+	printf("\n");
+
+	printf("Show the origin of each line of a file.\n");
+	printf("\n");
+
+	printf("Options:\n");
+
+	cli_opt_help_fprint(stdout, opts);
+}
+
+static int strintlen(size_t n)
+{
+	int len = 1;
+
+	while (n > 10) {
+		n /= 10;
+		len++;
+
+		if (len == INT_MAX)
+			break;
+	}
+
+	return len;
+}
+
+static int fmt_date(git_str *out, git_time_t time, int offset)
+{
+	time_t t;
+	struct tm gmt;
+
+	GIT_ASSERT_ARG(out);
+
+	t = (time_t)(time + offset * 60);
+
+	if (p_gmtime_r(&t, &gmt) == NULL)
+		return -1;
+
+	return git_str_printf(out, "%.4u-%02u-%02u %02u:%02u:%02u %+03d%02d",
+		gmt.tm_year + 1900, gmt.tm_mon + 1, gmt.tm_mday,
+		gmt.tm_hour, gmt.tm_min, gmt.tm_sec,
+		offset / 60, offset % 60);
+}
+
+static int print_standard(git_blame *blame)
+{
+	size_t max_line_number = 0;
+	int max_lineno_len, max_line_len, max_author_len = 0, max_path_len = 0;
+	const char *last_path = NULL;
+	const git_blame_line *line;
+	bool paths_differ = false;
+	git_str date_str = GIT_STR_INIT;
+	size_t i;
+	int ret = 0;
+
+	/* Compute the maximum size of things */
+	for (i = 0; i < git_blame_hunkcount(blame); i++) {
+		const git_blame_hunk *hunk = git_blame_hunk_byindex(blame, i);
+		size_t hunk_author_len = strlen(hunk->orig_signature->name);
+		size_t hunk_path_len = strlen(hunk->orig_path);
+		size_t hunk_max_line_number =
+			hunk->orig_start_line_number + hunk->lines_in_hunk;
+
+		if (hunk_max_line_number > max_line_number)
+			max_line_number = hunk_max_line_number;
+
+		if (hunk_author_len > INT_MAX)
+			max_author_len = INT_MAX;
+		else if ((int)hunk_author_len > max_author_len)
+			max_author_len = (int)hunk_author_len;
+
+		if (hunk_path_len > INT_MAX)
+			hunk_path_len = INT_MAX;
+		else if ((int)hunk_path_len > max_path_len)
+			max_path_len = (int)hunk_path_len;
+
+		if (!paths_differ && last_path != NULL &&
+		    strcmp(last_path, hunk->orig_path) != 0) {
+			paths_differ = true;
+		}
+
+		last_path = hunk->orig_path;
+	}
+
+	max_lineno_len = strintlen(max_line_number);
+
+	max_author_len--;
+
+	for (i = 1; i < git_blame_linecount(blame); i++) {
+		const git_blame_hunk *hunk = git_blame_hunk_byline(blame, i);
+		int oid_abbrev;
+
+		if (!hunk)
+			break;
+
+		oid_abbrev = hunk->boundary ? 7 : 8;
+		printf("%s%.*s ", hunk->boundary ? "^" : "",
+			oid_abbrev, git_oid_tostr_s(&hunk->orig_commit_id));
+
+		if (paths_differ)
+			printf("%-*.*s ", max_path_len, max_path_len, hunk->orig_path);
+
+		git_str_clear(&date_str);
+		if (fmt_date(&date_str,
+				hunk->orig_signature->when.time,
+				hunk->orig_signature->when.offset) < 0) {
+			ret = cli_error_git();
+			goto done;
+		}
+
+		if ((line = git_blame_line_byindex(blame, i)) == NULL) {
+			ret = cli_error_git();
+			goto done;
+		}
+
+		max_line_len = (int)min(line->len, INT_MAX);
+
+		printf("(%-*.*s %s %*" PRIuZ ") %.*s" ,
+			max_author_len, max_author_len, hunk->orig_signature->name,
+			date_str.ptr,
+			max_lineno_len, i,
+			max_line_len, line->ptr);
+		printf("\n");
+	}
+
+done:
+	git_str_dispose(&date_str);
+	return ret;
+}
+
+GIT_INLINE(uint32_t) oid_hashcode(const git_oid *oid)
+{
+	uint32_t hash;
+	memcpy(&hash, oid->id, sizeof(uint32_t));
+	return hash;
+}
+
+GIT_HASHSET_SETUP(git_blame_commitmap, const git_oid *, oid_hashcode, git_oid_equal);
+
+static int print_porcelain(git_blame *blame)
+{
+	git_blame_commitmap seen_ids = GIT_HASHSET_INIT;
+	size_t i, j;
+
+	for (i = 0; i < git_blame_hunkcount(blame); i++) {
+		const git_blame_line *line;
+		const git_blame_hunk *hunk = git_blame_hunk_byindex(blame, i);
+
+		for (j = 0; j < hunk->lines_in_hunk; j++) {
+			size_t line_number = hunk->final_start_line_number + j;
+			bool seen = git_blame_commitmap_contains(&seen_ids, &hunk->orig_commit_id);
+
+			printf("%s %" PRIuZ " %" PRIuZ,
+				git_oid_tostr_s(&hunk->orig_commit_id),
+				hunk->orig_start_line_number + j,
+				hunk->final_start_line_number + j);
+
+			if (!j)
+				printf(" %" PRIuZ, hunk->lines_in_hunk);
+
+			printf("\n");
+
+			if ((!j && !seen) || line_porcelain) {
+				printf("author %s\n", hunk->orig_signature->name);
+				printf("author-mail <%s>\n", hunk->orig_signature->email);
+				printf("author-time %" PRId64 "\n", hunk->orig_signature->when.time);
+				printf("author-tz %+03d%02d\n",
+					hunk->orig_signature->when.offset / 60,
+					hunk->orig_signature->when.offset % 60);
+
+				printf("committer %s\n", hunk->orig_committer->name);
+				printf("committer-mail <%s>\n", hunk->orig_committer->email);
+				printf("committer-time %" PRId64 "\n", hunk->orig_committer->when.time);
+				printf("committer-tz %+03d%02d\n",
+					hunk->orig_committer->when.offset / 60,
+					hunk->orig_committer->when.offset % 60);
+
+				printf("summary %s\n", hunk->summary);
+
+				/* TODO: previous */
+
+				printf("filename %s\n", hunk->orig_path);
+			}
+
+			if ((line = git_blame_line_byindex(blame, line_number)) == NULL)
+				return cli_error_git();
+
+			printf("\t%.*s\n", (int)min(line->len, INT_MAX),
+				line->ptr);
+
+			if (!seen)
+				git_blame_commitmap_add(&seen_ids, &hunk->orig_commit_id);
+		}
+	}
+
+	git_blame_commitmap_dispose(&seen_ids);
+	return 0;
+}
+
+int cmd_blame(int argc, char **argv)
+{
+	cli_repository_open_options open_opts = { argv + 1, argc - 1 };
+	git_blame_options blame_opts = GIT_BLAME_OPTIONS_INIT;
+	git_repository *repo = NULL;
+	git_str workdir_path = GIT_STR_INIT;
+	git_blame *blame = NULL;
+	cli_opt invalid_opt;
+	int ret = 0;
+
+	blame_opts.flags |= GIT_BLAME_USE_MAILMAP;
+
+	if (cli_opt_parse(&invalid_opt, opts, argv + 1, argc - 1, CLI_OPT_PARSE_GNU))
+		return cli_opt_usage_error(COMMAND_NAME, opts, &invalid_opt);
+
+	if (show_help) {
+		print_help();
+		return 0;
+	}
+
+	if (!file) {
+		ret = cli_error_usage("you must specify a file to blame");
+		goto done;
+	}
+
+	if (cli_repository_open(&repo, &open_opts) < 0)
+		return cli_error_git();
+
+	if ((ret = cli_resolve_path(&workdir_path, repo, file)) != 0)
+		goto done;
+
+	if (git_blame_file(&blame, repo, workdir_path.ptr, &blame_opts) < 0) {
+		ret = cli_error_git();
+		goto done;
+	}
+
+	if (porcelain || line_porcelain)
+		ret = print_porcelain(blame);
+	else
+		ret = print_standard(blame);
+
+done:
+	git_str_dispose(&workdir_path);
+	git_blame_free(blame);
+	git_repository_free(repo);
+	return ret;
+}

src/cli/main.c

@@ -32,6 +32,7 @@ const cli_opt_spec cli_common_opts[] = {
 };
 
 const cli_cmd_spec cli_cmds[] = {
+	{ "blame",       cmd_blame,       "Show the origin of each line of a file" },
 	{ "cat-file",    cmd_cat_file,    "Display an object in the repository" },
 	{ "clone",       cmd_clone,       "Clone a repository into a new directory" },
 	{ "config",      cmd_config,      "View or set configuration values " },