From 74eb8c68cf45d5679cf8ce569677dc5ca6a4b596 Mon Sep 17 00:00:00 2001
From: David Sterba <dsterba@suse.com>
Date: Fri, 30 Sep 2022 08:52:14 +0200
Subject: [PATCH] btrfs-progs: add template for common error messages

There are several generic errors that repeat the same message. Define a
template for such messages, with optional text.

Signed-off-by: David Sterba <dsterba@suse.com>
---
 common/messages.c | 23 +++++++++++++++++++++++
 common/messages.h | 10 ++++++++++
 2 files changed, 33 insertions(+)

diff --git a/common/messages.c b/common/messages.c
index 09716a40..0fc8c758 100644
--- a/common/messages.c
+++ b/common/messages.c
@@ -19,6 +19,10 @@
 #include "common/messages.h"
 #include "common/utils.h"
 
+static const char *common_error_string[] = {
+	[ERROR_MSG_MEMORY]	= "not enough memory",
+};
+
 __attribute__ ((format (printf, 1, 2)))
 void __btrfs_warning(const char *fmt, ...)
 {
@@ -113,3 +117,22 @@ void pr_verbose(int level, const char *fmt, ...)
 	vfprintf(stdout, fmt, args);
 	va_end(args);
 }
+
+/* Print common error message with optional data, appended after the generic text */
+__attribute__ ((format (printf, 2, 3)))
+void error_msg(enum common_error error, const char *msg, ...)
+{
+	const char *str = common_error_string[error];
+
+	if (msg) {
+		va_list args;
+
+		va_start(args, msg);
+		fprintf(stderr, "ERROR: %s: ", str);
+		vfprintf(stderr, msg, args);
+		va_end(args);
+		fputc('\n', stderr);
+	} else {
+		fprintf(stderr, "ERROR: %s\n", str);
+	}
+}
diff --git a/common/messages.h b/common/messages.h
index 915f760e..e695462b 100644
--- a/common/messages.h
+++ b/common/messages.h
@@ -130,4 +130,14 @@ void internal_error(const char *fmt, ...);
 __attribute__ ((format (printf, 2, 3)))
 void pr_verbose(int level, const char *fmt, ...);
 
+/*
+ * Commonly used errors
+ */
+enum common_error {
+	ERROR_MSG_MEMORY,
+};
+
+__attribute__ ((format (printf, 2, 3)))
+void error_msg(enum common_error error, const char *msg, ...);
+
 #endif