Reduce code size a bit

Do some changes that reduce the code size a bit.

devices.c

@@ -94,29 +94,22 @@ void wait_for_device(char *real_device_name, int *timeout, const char *device, i
    * do a very simple and stupid polling loop to wait until the
    * requested device is present. This could be improved a bit,
    * but for now it's good enough. */
-  time_t start;
-  struct timeval tv;
-  int r, have_device;
+  time_t start, current;
+  int have_device;
   static int have_shown_message_timeout;
   int type;
   unsigned int major, minor;
   char uuid[16];
 
   /* Parse device information */
   if (!is_valid_device_name(device, &type, &major, &minor, uuid))
-    panic(0, LOG_PREFIX, "Unsupported device specified: ", device, NULL);
+    panic(0, "Unsupported device specified: ", device, NULL);
 
-  if (delay) {
-    struct timespec req = { delay, 0 };
-    struct timespec rem;
-    (void)nanosleep(&req, &rem);
-  }
+  if (delay)
+    (void)sleep(delay);
 
   /* Our timeout starts *after* the rootdelay. */
-  r = gettimeofday(&tv, NULL);
-  if (r < 0)
-    panic(errno, LOG_PREFIX, "Couldn't determine current time for timeout", NULL);
-  start = tv.tv_sec;
+  start = time(NULL);
 
   if (type == WANT_NAME) {
     set_buf(real_device_name, MAX_PATH_LEN, device, NULL);
@@ -126,17 +119,15 @@ void wait_for_device(char *real_device_name, int *timeout, const char *device, i
   }
 
   while (have_device) {
-    r = gettimeofday(&tv, NULL);
-    if (r < 0)
-      panic(errno, LOG_PREFIX, "Couldn't determine current time for timeout", NULL);
-    if (*timeout > 0 && tv.tv_sec - start > *timeout)
-      panic(0, LOG_PREFIX, "Timeout while waiting for devices for / (and possibly /usr) filesystems to appear "
-                           "(did you specify the correct ones?)", NULL);
+    current = time(NULL);
+    if (*timeout > 0 && current - start > *timeout)
+      panic(0, "Timeout while waiting for devices for / (and possibly /usr) filesystems to appear "
+               "(did you specify the correct ones?)", NULL);
     /* In case this takes longer, show a nice message so the user has SOME
      * idea of what's going on here. */
-    if (tv.tv_sec - start > DEVICE_MESSAGE_TIMEOUT && !have_shown_message_timeout) {
+    if (current - start > DEVICE_MESSAGE_TIMEOUT && !have_shown_message_timeout) {
       have_shown_message_timeout = 1;
-      warn(LOG_PREFIX, "Waiting for ", device, " to appear...", NULL);
+      warn("Waiting for ", device, " to appear...", NULL);
     }
     /* Sleep for DEVICE_POLL_MSEC milliseconds, then poll again. */
     struct timespec req = { 0, DEVICE_POLL_MSEC * 1000 * 1000 };
@@ -152,10 +143,8 @@ void wait_for_device(char *real_device_name, int *timeout, const char *device, i
   /* Make sure we record how many seconds on the timeout are left,
    * because this function may be called again for the /usr filesystem. */
   if (*timeout > 0) {
-    r = gettimeofday(&tv, NULL);
-    if (r < 0)
-      panic(errno, LOG_PREFIX, "Couldn't determine current time for timeout", NULL);
-    *timeout = tv.tv_sec - start;
+    current = time(NULL);
+    *timeout = current - start;
     if (*timeout <= 0)
       *timeout = 1;
   }
@@ -265,12 +254,11 @@ int is_valid_device_name(const char *device_name, int *type, unsigned int* major
   if (device_name[0] == '0' && device_name[1] == 'x') {
     x = strtoul(device_name + 2, &endptr, 16);
     if (endptr && !*endptr) {
-      if (type)
+      if (type) {
         *type = WANT_MAJMIN;
-      if (major)
         *major = (int)(x >> 8);
-      if (minor)
         *minor = (int)(x & 0xff);
+      }
       return 1;
     }
     return 0;

log.c

@@ -43,7 +43,7 @@ void panic(int err, ...)
    * because a kernel panic obscures the message. But we need to cause
    * a kernel panic (by PID 1 exiting), because if the user tells the
    * kernel to reboot on panic, we want to make sure this happens. */
-  warn(LOG_PREFIX, "Will cause kernel panic in 10s...", NULL);
+  warn("Will cause kernel panic in 10s...", NULL);
   sleep(10);
   _exit(1);
 }
@@ -61,40 +61,25 @@ void showmsgv(va_list ap, const char *before1, const char *after1, const char *a
   /* Don't use stdio functions, because we link statically
    * and they bloat the binary. */
 
-  va_list ap_count;
-  int argc = 0;
-  int i;
+  int argc = 1;
   int fd;
   struct iovec iov[32];
-  unsigned extra_arg_count = !!before1 + !!after1 + !!after2;
-  unsigned first_arg = 0;
-
-  va_copy(ap_count, ap);
-  while (va_arg(ap_count, const char *)) {
-    argc++;
-  }
-  va_end(ap_count);
-
-  /* Try to open /dev/kmsg, log to stderr if not possible */
-  fd = open(KMSG_FILENAME, O_WRONLY | O_NOCTTY | O_CLOEXEC);
-  if (fd < 0)
-    fd = 2;
-
-  /* We only support a fixed number of arguments arguments. */
-  if (argc + 1 + extra_arg_count > 32)
-    argc = 31 - extra_arg_count;
+  unsigned extra_arg_count = !!after1 + !!after2;
+  const char *arg;
 
   if (before1) {
-    iov[0].iov_base = (char *)before1;
-    iov[0].iov_len = strlen(before1);
+    iov[1].iov_base = (char *)before1;
+    iov[1].iov_len = strlen(before1);
     argc++;
-    first_arg = 1;
   }
 
-  for (i = first_arg; i < argc; i++) {
-    const char *arg = va_arg(ap, const char *);
-    iov[i].iov_base = (char *)arg;
-    iov[i].iov_len = strlen(arg);
+  while ((arg = va_arg(ap, const char *))) {
+    iov[argc].iov_base = (char *)arg;
+    iov[argc].iov_len = strlen(arg);
+    argc++;
+    /* We only support a fixed number of arguments arguments. */
+    if (argc + 1 + extra_arg_count > 32)
+      break;
   }
 
   if (after1) {
@@ -109,9 +94,20 @@ void showmsgv(va_list ap, const char *before1, const char *after1, const char *a
     argc++;
   }
 
+  if (argc == 1)
+    return;
+
   iov[argc].iov_base = (char *)"\n";
   iov[argc].iov_len = 1;
 
+  iov[0].iov_base = (char *)LOG_PREFIX;
+  iov[0].iov_len = sizeof(LOG_PREFIX) - 1;
+
+  /* Try to open /dev/kmsg, log to stderr if not possible */
+  fd = open(KMSG_FILENAME, O_WRONLY | O_NOCTTY | O_CLOEXEC);
+  if (fd < 0)
+    fd = 2;
+
   writev(fd, iov, argc + 1);
 
   if (fd >= 3)