Merge branch 'ab/usage-die-message'

Code clean-up to hide vreportf() from public API.

* ab/usage-die-message:
  config API: use get_error_routine(), not vreportf()
  usage.c + gc: add and use a die_message_errno()
  gc: return from cmd_gc(), don't call exit()
  usage.c API users: use die_message() for error() + exit 128
  usage.c API users: use die_message() for "fatal :" + exit 128
  usage.c: add a die_message() routine

builtin/fast-import.c

@@ -401,16 +401,18 @@ static void dump_marks(void);
 
 static NORETURN void die_nicely(const char *err, va_list params)
 {
+	va_list cp;
 	static int zombie;
-	char message[2 * PATH_MAX];
+	report_fn die_message_fn = get_die_message_routine();
 
-	vsnprintf(message, sizeof(message), err, params);
+	va_copy(cp, params);
-	fputs("fatal: ", stderr);
+	die_message_fn(err, params);
-	fputs(message, stderr);
-	fputc('\n', stderr);
 
 	if (!zombie) {
+		char message[2 * PATH_MAX];
+
 		zombie = 1;
+		vsnprintf(message, sizeof(message), err, cp);
 		write_crash_report(message);
 		end_packfile();
 		unkeep_all_packs();

builtin/gc.c

@@ -470,7 +470,8 @@ static const char *lock_repo_for_gc(int force, pid_t* ret_pid)
 /*
  * Returns 0 if there was no previous error and gc can proceed, 1 if
  * gc should not proceed due to an error in the last run. Prints a
- * message and returns -1 if an error occurred while reading gc.log
+ * message and returns with a non-[01] status code if an error occurred
+ * while reading gc.log
  */
 static int report_last_gc_error(void)
 {
@@ -484,7 +485,7 @@ static int report_last_gc_error(void)
 		if (errno == ENOENT)
 			goto done;
 
-		ret = error_errno(_("cannot stat '%s'"), gc_log_path);
+		ret = die_message_errno(_("cannot stat '%s'"), gc_log_path);
 		goto done;
 	}
 
@@ -493,7 +494,7 @@ static int report_last_gc_error(void)
 
 	len = strbuf_read_file(&sb, gc_log_path, 0);
 	if (len < 0)
-		ret = error_errno(_("cannot read '%s'"), gc_log_path);
+		ret = die_message_errno(_("cannot read '%s'"), gc_log_path);
 	else if (len > 0) {
 		/*
 		 * A previous gc failed.  Report the error, and don't
@@ -611,12 +612,13 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 		}
 		if (detach_auto) {
 			int ret = report_last_gc_error();
-			if (ret < 0)
+
-				/* an I/O error occurred, already reported */
-				exit(128);
 			if (ret == 1)
 				/* Last gc --auto failed. Skip this one. */
 				return 0;
+			else if (ret)
+				/* an I/O error occurred, already reported */
+				return ret;
 
 			if (lock_repo_for_gc(force, &pid))
 				return 0;

builtin/notes.c

@@ -200,11 +200,12 @@ static void prepare_note_data(const struct object_id *object, struct note_data *
 static void write_note_data(struct note_data *d, struct object_id *oid)
 {
 	if (write_object_file(d->buf.buf, d->buf.len, blob_type, oid)) {
-		error(_("unable to write note object"));
+		int status = die_message(_("unable to write note object"));
+
 		if (d->edit_path)
-			error(_("the note contents have been left in %s"),
+			die_message(_("the note contents have been left in %s"),
 				    d->edit_path);
-		exit(128);
+		exit(status);
 	}
 }
 

config.c

@@ -2555,11 +2555,12 @@ void git_die_config(const char *key, const char *err, ...)
 {
 	const struct string_list *values;
 	struct key_value_info *kv_info;
+	report_fn error_fn = get_error_routine();
 
 	if (err) {
 		va_list params;
 		va_start(params, err);
-		vreportf("error: ", err, params);
+		error_fn(err, params);
 		va_end(params);
 	}
 	values = git_config_get_value_multi(key);

git-compat-util.h

@@ -498,11 +498,12 @@ static inline int git_has_dir_sep(const char *path)
 struct strbuf;
 
 /* General helper functions */
-void vreportf(const char *prefix, const char *err, va_list params);
 NORETURN void usage(const char *err);
 NORETURN void usagef(const char *err, ...) __attribute__((format (printf, 1, 2)));
 NORETURN void die(const char *err, ...) __attribute__((format (printf, 1, 2)));
 NORETURN void die_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
+int die_message(const char *err, ...) __attribute__((format (printf, 1, 2)));
+int die_message_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
 int error_errno(const char *err, ...) __attribute__((format (printf, 1, 2)));
 void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
@@ -537,6 +538,7 @@ static inline int const_error(void)
 typedef void (*report_fn)(const char *, va_list params);
 
 void set_die_routine(NORETURN_PTR report_fn routine);
+report_fn get_die_message_routine(void);
 void set_error_routine(report_fn routine);
 report_fn get_error_routine(void);
 void set_warn_routine(report_fn routine);

http-backend.c

@@ -659,8 +659,9 @@ static NORETURN void die_webcgi(const char *err, va_list params)
 {
 	if (dead <= 1) {
 		struct strbuf hdr = STRBUF_INIT;
+		report_fn die_message_fn = get_die_message_routine();
 
-		vreportf("fatal: ", err, params);
+		die_message_fn(err, params);
 
 		http_status(&hdr, 500, "Internal Server Error");
 		hdr_nocache(&hdr);

parse-options.c

@@ -1076,6 +1076,6 @@ void NORETURN usage_msg_opt(const char *msg,
 		   const char * const *usagestr,
 		   const struct option *options)
 {
-	fprintf(stderr, "fatal: %s\n\n", msg);
+	die_message("%s\n", msg); /* The extra \n is intentional */
 	usage_with_options(usagestr, options);
 }

run-command.c

@@ -340,15 +340,6 @@ static void child_close_pair(int fd[2])
 	child_close(fd[1]);
 }
 
-/*
- * parent will make it look like the child spewed a fatal error and died
- * this is needed to prevent changes to t0061.
- */
-static void fake_fatal(const char *err, va_list params)
-{
-	vreportf("fatal: ", err, params);
-}
-
 static void child_error_fn(const char *err, va_list params)
 {
 	const char msg[] = "error() should not be called in child\n";
@@ -372,9 +363,10 @@ static void NORETURN child_die_fn(const char *err, va_list params)
 static void child_err_spew(struct child_process *cmd, struct child_err *cerr)
 {
 	static void (*old_errfn)(const char *err, va_list params);
+	report_fn die_message_routine = get_die_message_routine();
 
 	old_errfn = get_error_routine();
-	set_error_routine(fake_fatal);
+	set_error_routine(die_message_routine);
 	errno = cerr->syserr;
 
 	switch (cerr->err) {
@@ -1072,7 +1064,9 @@ static void *run_thread(void *data)
 
 static NORETURN void die_async(const char *err, va_list params)
 {
-	vreportf("fatal: ", err, params);
+	report_fn die_message_fn = get_die_message_routine();
+
+	die_message_fn(err, params);
 
 	if (in_async()) {
 		struct async *async = pthread_getspecific(async_key);

usage.c

@@ -6,7 +6,7 @@
 #include "git-compat-util.h"
 #include "cache.h"
 
-void vreportf(const char *prefix, const char *err, va_list params)
+static void vreportf(const char *prefix, const char *err, va_list params)
 {
 	char msg[4096];
 	char *p, *pend = msg + sizeof(msg);
@@ -55,6 +55,12 @@ static NORETURN void usage_builtin(const char *err, va_list params)
 	exit(129);
 }
 
+static void die_message_builtin(const char *err, va_list params)
+{
+	trace2_cmd_error_va(err, params);
+	vreportf("fatal: ", err, params);
+}
+
 /*
  * We call trace2_cmd_error_va() in the below functions first and
  * expect it to va_copy 'params' before using it (because an 'ap' can
@@ -62,10 +68,9 @@ static NORETURN void usage_builtin(const char *err, va_list params)
  */
 static NORETURN void die_builtin(const char *err, va_list params)
 {
-	trace2_cmd_error_va(err, params);
+	report_fn die_message_fn = get_die_message_routine();
-
-	vreportf("fatal: ", err, params);
 
+	die_message_fn(err, params);
 	exit(128);
 }
 
@@ -109,6 +114,7 @@ static int die_is_recursing_builtin(void)
  * (ugh), so keep things static. */
 static NORETURN_PTR report_fn usage_routine = usage_builtin;
 static NORETURN_PTR report_fn die_routine = die_builtin;
+static report_fn die_message_routine = die_message_builtin;
 static report_fn error_routine = error_builtin;
 static report_fn warn_routine = warn_builtin;
 static int (*die_is_recursing)(void) = die_is_recursing_builtin;
@@ -118,6 +124,11 @@ void set_die_routine(NORETURN_PTR report_fn routine)
 	die_routine = routine;
 }
 
+report_fn get_die_message_routine(void)
+{
+	return die_message_routine;
+}
+
 void set_error_routine(report_fn routine)
 {
 	error_routine = routine;
@@ -211,6 +222,29 @@ void NORETURN die_errno(const char *fmt, ...)
 	va_end(params);
 }
 
+#undef die_message
+int die_message(const char *err, ...)
+{
+	va_list params;
+
+	va_start(params, err);
+	die_message_routine(err, params);
+	va_end(params);
+	return 128;
+}
+
+#undef die_message_errno
+int die_message_errno(const char *fmt, ...)
+{
+	char buf[1024];
+	va_list params;
+
+	va_start(params, fmt);
+	die_message_routine(fmt_with_err(buf, sizeof(buf), fmt), params);
+	va_end(params);
+	return 128;
+}
+
 #undef error_errno
 int error_errno(const char *fmt, ...)
 {