[PATCH v4 03/15] bugreport: gather git version and build info

[Emily Shaffer <emilyshaffer@google.com>]

Knowing which version of Git a user has and how it was built allows us
to more precisely pin down the circumstances when a certain issue
occurs, so teach bugreport how to tell us the same output as 'git
version --build-options'.

It's not ideal to directly call 'git version --build-options' because
that output goes to stdout. Instead, wrap the version string in a helper
within help.[ch] library, and call that helper from within the bugreport
library.

Signed-off-by: Emily Shaffer <emilyshaffer@google.com>
---
 bugreport.c | 23 ++++++++++++++++++++++-
 help.c      | 45 +++++++++++++++++++++++++++------------------
 help.h      |  1 +
 3 files changed, 50 insertions(+), 19 deletions(-)

diff --git a/bugreport.c b/bugreport.c
index 5495b31674..59d8b5a3af 100644
--- a/bugreport.c
+++ b/bugreport.c
@@ -1,8 +1,20 @@
-#include "builtin.h"
+#include "cache.h"
 #include "parse-options.h"
 #include "stdio.h"
 #include "strbuf.h"
 #include "time.h"
+#include "help.h"
+
+static void get_system_info(struct strbuf *sys_info)
+{
+	struct strbuf version_info = STRBUF_INIT;
+
+	/* get git version from native cmd */
+	strbuf_addstr(sys_info, "git version:\n");
+	list_version_info(&version_info, 1);
+	strbuf_addbuf(sys_info, &version_info);
+	strbuf_complete_line(sys_info);
+}
 
 static const char * const bugreport_usage[] = {
 	N_("git bugreport [-o|--output <file>]"),
@@ -32,6 +44,11 @@ static int get_bug_template(struct strbuf *template)
 	return 0;
 }
 
+static void get_header(struct strbuf *buf, const char *title)
+{
+	strbuf_addf(buf, "\n\n[%s]\n", title);
+}
+
 int cmd_main(int argc, const char **argv)
 {
 	struct strbuf buffer = STRBUF_INIT;
@@ -60,6 +77,10 @@ int cmd_main(int argc, const char **argv)
 
 	get_bug_template(&buffer);
 
+	// add other contents
+	get_header(&buffer, "System Info");
+	get_system_info(&buffer);
+
 	report = fopen_for_writing(report_path.buf);
 	strbuf_write(&buffer, report);
 	fclose(report);
diff --git a/help.c b/help.c
index a21487db77..a43693fca5 100644
--- a/help.c
+++ b/help.c
@@ -622,8 +622,33 @@ const char *help_unknown_cmd(const char *cmd)
 	exit(1);
 }
 
+void list_version_info(struct strbuf *buf, int build_options)
+{
+	strbuf_reset(buf);
+	/*
+	 * The format of this string should be kept stable for compatibility
+	 * with external projects that rely on the output of "git version".
+	 *
+	 * Always show the version, even if other options are given.
+	 */
+	strbuf_addf(buf, "git version %s\n", git_version_string);
+
+	if (build_options) {
+		strbuf_addf(buf, "cpu: %s\n", GIT_HOST_CPU);
+		if (git_built_from_commit_string[0])
+			strbuf_addf(buf, "built from commit: %s\n",
+			       git_built_from_commit_string);
+		else
+			strbuf_addf(buf, "no commit associated with this build\n");
+		strbuf_addf(buf, "sizeof-long: %d\n", (int)sizeof(long));
+		strbuf_addf(buf, "sizeof-size_t: %d\n", (int)sizeof(size_t));
+		/* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
+	}
+}
+
 int cmd_version(int argc, const char **argv, const char *prefix)
 {
+	struct strbuf buf = STRBUF_INIT;
 	int build_options = 0;
 	const char * const usage[] = {
 		N_("git version [<options>]"),
@@ -637,25 +662,9 @@ int cmd_version(int argc, const char **argv, const char *prefix)
 
 	argc = parse_options(argc, argv, prefix, options, usage, 0);
 
-	/*
-	 * The format of this string should be kept stable for compatibility
-	 * with external projects that rely on the output of "git version".
-	 *
-	 * Always show the version, even if other options are given.
-	 */
-	printf("git version %s\n", git_version_string);
+	list_version_info(&buf, build_options);
+	printf("%s", buf.buf);
 
-	if (build_options) {
-		printf("cpu: %s\n", GIT_HOST_CPU);
-		if (git_built_from_commit_string[0])
-			printf("built from commit: %s\n",
-			       git_built_from_commit_string);
-		else
-			printf("no commit associated with this build\n");
-		printf("sizeof-long: %d\n", (int)sizeof(long));
-		printf("sizeof-size_t: %d\n", (int)sizeof(size_t));
-		/* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
-	}
 	return 0;
 }
 
diff --git a/help.h b/help.h
index 9071894e8c..54f6b5f793 100644
--- a/help.h
+++ b/help.h
@@ -37,6 +37,7 @@ void add_cmdname(struct cmdnames *cmds, const char *name, int len);
 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes);
 int is_in_cmdlist(struct cmdnames *cmds, const char *name);
 void list_commands(unsigned int colopts, struct cmdnames *main_cmds, struct cmdnames *other_cmds);
+void list_version_info(struct strbuf *buf, int build_options);
 
 /*
  * call this to die(), when it is suspected that the user mistyped a
-- 
2.24.1.735.g03f4e72817-goog