usr.bin: osh: Add kmsg command for kernel messages

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 25 insertions, 0 deletions

diff --git a/usr.bin/osh/osh.c b/usr.bin/osh/osh.c
index c45d9c8..9b4e9ab 100644
--- a/usr.bin/osh/osh.c
+++ b/usr.bin/osh/osh.c
@@ -49,6 +49,7 @@
     "echo     - Print the arguments to the console\n" \
     "reboot   - Reboot the machine\n" \
     "shutdown - Power off the machine\n" \
+    "kmsg     - Print kernel message buffer\n" \
     "exit     - Exit the shell\n"
 
 #define PROMPT "[root::osmora]~ "
@@ -87,6 +88,29 @@ cmd_shutdown(int fd, int argc, char *argv[])
 }
 
 void
+cmd_kmsg(int fd, int argc, char *argv[])
+{
+    int mfd;
+    ssize_t retval;
+    char linebuf[256];
+
+    if ((mfd = open("/dev/kmsg", O_RDONLY)) < 0) {
+        return;
+    }
+
+    for (;;) {
+        retval = read(mfd, linebuf, sizeof(linebuf) - 1);
+        if (retval <= 0) {
+            break;
+        }
+        linebuf[retval] = '\0';
+        prcons(fd, linebuf);
+    }
+
+    close(mfd);
+}
+
+void
 cmd_echo(int fd, int argc, char *argv[])
 {
     for (i = 1; i < argc; i++) {
@@ -171,6 +195,7 @@ struct command cmds[] = {
     {"exit", cmd_exit},
     {"reboot", cmd_reboot},
     {"shutdown", cmd_shutdown},
+    {"kmsg", cmd_kmsg},
     {NULL, NULL}
 };