From: Lennart Poettering <lennart@poettering.net>
Date: Thu, 22 Jan 2015 02:47:46 +0000 (+0100)
Subject: log: add new log output mode, that prints to console, but prefixes with syslog priority
X-Git-Tag: v219~386
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=aca83a53ee1dd01beafcd07c55c4cd6c3efb4224;ds=sidebyside

log: add new log output mode, that prints to console, but prefixes with syslog priority

This is useful when we execute our own programs, reading output from its
STDERR, and want to retain priority information.
---

diff --git a/src/shared/log.c b/src/shared/log.c
index af1a932c8..f8c16de77 100644
--- a/src/shared/log.c
+++ b/src/shared/log.c
@@ -314,14 +314,19 @@ static int write_to_console(
                 const char *object,
                 const char *buffer) {
 
-        char location[64];
-        struct iovec iovec[5] = {};
+        char location[64], prefix[1 + DECIMAL_STR_MAX(int) + 2];
+        struct iovec iovec[6] = {};
         unsigned n = 0;
         bool highlight;
 
         if (console_fd < 0)
                 return 0;
 
+        if (log_target == LOG_TARGET_CONSOLE_PREFIXED) {
+                sprintf(prefix, "<%i>", level);
+                IOVEC_SET_STRING(iovec[n++], prefix);
+        }
+
         highlight = LOG_PRI(level) <= LOG_ERR && show_color;
 
         if (show_location) {
@@ -1016,7 +1021,8 @@ int log_show_location_from_string(const char *e) {
 }
 
 bool log_on_console(void) {
-        if (log_target == LOG_TARGET_CONSOLE)
+        if (log_target == LOG_TARGET_CONSOLE ||
+            log_target == LOG_TARGET_CONSOLE_PREFIXED)
                 return true;
 
         return syslog_fd < 0 && kmsg_fd < 0 && journal_fd < 0;
@@ -1024,6 +1030,7 @@ bool log_on_console(void) {
 
 static const char *const log_target_table[_LOG_TARGET_MAX] = {
         [LOG_TARGET_CONSOLE] = "console",
+        [LOG_TARGET_CONSOLE_PREFIXED] = "console-prefixed",
         [LOG_TARGET_KMSG] = "kmsg",
         [LOG_TARGET_JOURNAL] = "journal",
         [LOG_TARGET_JOURNAL_OR_KMSG] = "journal-or-kmsg",
diff --git a/src/shared/log.h b/src/shared/log.h
index d15d7c8f9..2889e1e77 100644
--- a/src/shared/log.h
+++ b/src/shared/log.h
@@ -34,6 +34,7 @@
 
 typedef enum LogTarget{
         LOG_TARGET_CONSOLE,
+        LOG_TARGET_CONSOLE_PREFIXED,
         LOG_TARGET_KMSG,
         LOG_TARGET_JOURNAL,
         LOG_TARGET_JOURNAL_OR_KMSG,