commit 7425fd1b231fcdb3c260877a13f794a0c7361e80
author Ken Sumrall <ksumrall@android.com> Wed Apr 03 13:43:11 2013 -0700
committer Ken Sumrall <ksumrall@android.com> Thu Apr 11 20:03:47 2013 -0700
tree 0c54939f1e54f23821ba305c093435fc620f73a8
parent c796ed97466510dd5239008554decbe72825e19c

klog: Have klog_write() call klog_init() if needed

Also change klog_init() to do nothing if already initialized.

Change-Id: Ia2dfe914c9d9fd119fb8939508d57b15c9884663

include/cutils/klog.h

diff --git a/include/cutils/klog.h b/include/cutils/klog.h
index 1335543..ba728ac 100644
--- a/include/cutils/klog.h
+++ b/include/cutils/klog.h
@@ -17,12 +17,18 @@
 #ifndef _CUTILS_KLOG_H_
 #define _CUTILS_KLOG_H_
 
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
 void klog_init(void);
 void klog_set_level(int level);
 void klog_close(void);
 void klog_write(int level, const char *fmt, ...)
     __attribute__ ((format(printf, 2, 3)));
 
+__END_DECLS
+
 #define KLOG_ERROR(tag,x...)   klog_write(3, "<3>" tag ": " x)
 #define KLOG_WARNING(tag,x...) klog_write(4, "<4>" tag ": " x)
 #define KLOG_NOTICE(tag,x...)  klog_write(5, "<5>" tag ": " x)

libcutils/klog.c

diff --git a/libcutils/klog.c b/libcutils/klog.c
index b586a57..812af3b 100644
--- a/libcutils/klog.c
+++ b/libcutils/klog.c
@@ -35,6 +35,9 @@
 void klog_init(void)
 {
     static const char *name = "/dev/__kmsg__";
+
+    if (klog_fd >= 0) return; /* Already initialized */
+
     if (mknod(name, S_IFCHR | 0600, (1 << 8) | 11) == 0) {
         klog_fd = open(name, O_WRONLY);
         fcntl(klog_fd, F_SETFD, FD_CLOEXEC);
@@ -50,7 +53,7 @@
     va_list ap;
 
     if (level > klog_level) return;
-    if (klog_fd < 0) return;
+    if (klog_fd < 0) klog_init();
 
     va_start(ap, fmt);
     vsnprintf(buf, LOG_BUF_MAX, fmt, ap);