syslog: add minimal syslog/kmsg bridge syslogd

[elogind.git] / src / log.c

diff --git a/src/log.c b/src/log.c
index 8c20b9c9deda5cbd4fded3626fa2dc99a54373dc..3c42e8e51795dc4f7928707c9d7f9a46516f06a5 100644 (file)
--- a/src/log.c
+++ b/src/log.c
@@ -32,7 +32,6 @@
 #include "macro.h"
 
 #define SYSLOG_TIMEOUT_USEC (5*USEC_PER_SEC)
-#define LOG_BUFFER_MAX 1024
 
 static LogTarget log_target = LOG_TARGET_CONSOLE;
 static int log_max_level = LOG_INFO;
@@ -73,7 +72,7 @@ static int log_open_console(void) {
                         return console_fd;
                 }
 
-                log_info("Succesfully opened /dev/console for logging.");
+                log_debug("Succesfully opened /dev/console for logging.");
         } else
                 console_fd = STDERR_FILENO;
 
@@ -99,7 +98,7 @@ static int log_open_kmsg(void) {
                 return -errno;
         }
 
-        log_info("Succesfully opened /dev/kmsg for logging.");
+        log_debug("Succesfully opened /dev/kmsg for logging.");
 
         return 0;
 }
@@ -146,7 +145,7 @@ static int log_open_syslog(void) {
                 goto fail;
         }
 
-        log_info("Succesfully opened syslog for logging.");
+        log_debug("Succesfully opened syslog for logging.");
 
         return 0;
 
@@ -249,6 +248,11 @@ static int write_to_syslog(
         char header_priority[16], header_time[64], header_pid[16];
         struct iovec iovec[5];
         struct msghdr msghdr;
+        union {
+                struct cmsghdr cmsghdr;
+                uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
+        } control;
+        struct ucred *ucred;
         time_t t;
         struct tm *tm;
 
@@ -275,9 +279,21 @@ static int write_to_syslog(
         IOVEC_SET_STRING(iovec[3], header_pid);
         IOVEC_SET_STRING(iovec[4], buffer);
 
+        zero(control);
+        control.cmsghdr.cmsg_level = SOL_SOCKET;
+        control.cmsghdr.cmsg_type = SCM_CREDENTIALS;
+        control.cmsghdr.cmsg_len = CMSG_LEN(sizeof(struct ucred));
+
+        ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
+        ucred->pid = getpid();
+        ucred->uid = getuid();
+        ucred->gid = getgid();
+
         zero(msghdr);
         msghdr.msg_iov = iovec;
         msghdr.msg_iovlen = ELEMENTSOF(iovec);
+        msghdr.msg_control = &control;
+        msghdr.msg_controllen = control.cmsghdr.cmsg_len;
 
         if (sendmsg(syslog_fd, &msghdr, MSG_NOSIGNAL) < 0)
                 return -errno;
@@ -331,7 +347,7 @@ static int log_dispatch(
 
         do {
                 char *e;
-                int k;
+                int k = 0;
 
                 buffer += strspn(buffer, NEWLINE);
 
@@ -344,24 +360,26 @@ static int log_dispatch(
                 if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
                     log_target == LOG_TARGET_SYSLOG) {
 
-                        if ((r = write_to_syslog(level, file, line, func, buffer)) < 0) {
+                        if ((k = write_to_syslog(level, file, line, func, buffer)) < 0) {
                                 log_close_syslog();
                                 log_open_kmsg();
-                        } else if (r > 0)
+                        } else if (k > 0)
                                 r++;
                 }
 
-                if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
-                    log_target == LOG_TARGET_KMSG) {
+                if (k <= 0 &&
+                    (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
+                     log_target == LOG_TARGET_KMSG)) {
 
-                        if ((r = write_to_kmsg(level, file, line, func, buffer)) < 0) {
+                        if ((k = write_to_kmsg(level, file, line, func, buffer)) < 0) {
                                 log_close_kmsg();
                                 log_open_console();
-                        } else if (r > 0)
+                        } else if (k > 0)
                                 r++;
                 }
 
-                if ((k = write_to_console(level, file, line, func, buffer)) < 0)
+                if (k <= 0 &&
+                    (k = write_to_console(level, file, line, func, buffer)) < 0)
                         return k;
 
                 buffer = e;
@@ -398,7 +416,7 @@ int log_meta(
         const char *func,
         const char *format, ...) {
 
-        char buffer[LOG_BUFFER_MAX];
+        char buffer[LINE_MAX];
         int saved_errno, r;
         va_list ap;
 
@@ -425,7 +443,7 @@ void log_assert(
         const char *func,
         const char *format, ...) {
 
-        static char buffer[LOG_BUFFER_MAX];
+        static char buffer[LINE_MAX];
         int saved_errno = errno;
         va_list ap;