logd: add internal prdebug function
Usage: android::prdebug(const char *fmt, ...) __printflike(1, 2);
Will add logd prefix tag, log as debug priority in kernel logs,
and will suffix a newline if one is not supplied. To be used to
aid debugging of the logger only.
Change-Id: I217326ef34dc4eb0ea076bacb7a7a8b564c931c3
diff --git a/logd/LogUtils.h b/logd/LogUtils.h
index fd4800e..aa4b6e1 100644
--- a/logd/LogUtils.h
+++ b/logd/LogUtils.h
@@ -17,6 +17,7 @@
#ifndef _LOGD_LOG_UTILS_H__
#define _LOGD_LOG_UTILS_H__
+#include <sys/cdefs.h>
#include <sys/types.h>
#include <log/log.h>
@@ -29,6 +30,7 @@
// Furnished in main.cpp. Caller must own and free returned value
char *uidToName(uid_t uid);
+void prdebug(const char *fmt, ...) __printflike(1, 2);
// Furnished in LogStatistics.cpp. Caller must own and free returned value
char *pidToName(pid_t pid);
diff --git a/logd/main.cpp b/logd/main.cpp
index ba56e57..9cec313 100644
--- a/logd/main.cpp
+++ b/logd/main.cpp
@@ -211,10 +211,32 @@
return (flag & BOOL_DEFAULT_FLAG_TRUE_FALSE) != BOOL_DEFAULT_FALSE;
}
-// Remove the static, and use this variable
-// globally for debugging if necessary. eg:
-// write(fdDmesg, "I am here\n", 10);
static int fdDmesg = -1;
+void inline android::prdebug(const char *fmt, ...) {
+ if (fdDmesg < 0) {
+ return;
+ }
+
+ static const char message[] = {
+ KMSG_PRIORITY(LOG_DEBUG), 'l', 'o', 'g', 'd', ':', ' '
+ };
+ char buffer[256];
+ memcpy(buffer, message, sizeof(message));
+
+ va_list ap;
+ va_start(ap, fmt);
+ int n = vsnprintf(buffer + sizeof(message),
+ sizeof(buffer) - sizeof(message), fmt, ap);
+ va_end(ap);
+ if (n > 0) {
+ buffer[sizeof(buffer) - 1] = '\0';
+ if (!strchr(buffer, '\n')) {
+ buffer[sizeof(buffer) - 2] = '\0';
+ strlcat(buffer, "\n", sizeof(buffer));
+ }
+ write(fdDmesg, buffer, strlen(buffer));
+ }
+}
static sem_t uidName;
static uid_t uid;