summaryrefslogtreecommitdiff
path: root/linux/src/kernel/printk.c
diff options
context:
space:
mode:
authorThomas Bushnell <thomas@gnu.org>1999-04-26 05:58:44 +0000
committerThomas Bushnell <thomas@gnu.org>1999-04-26 05:58:44 +0000
commit86297c41a26f18d924e64fc93321c59cbc4c48dd (patch)
tree376954c6b95b735d361875319a1a2a9db6a27527 /linux/src/kernel/printk.c
parent851137902d3e7ad87af177487df3eea53e940a1c (diff)
1998-11-30 OKUJI Yoshinori <okuji@kuicr.kyoto-u.ac.jp>
Clean up linux emulation code to make it architecture-independent as much as possible. * linux: Renamed from linuxdev. * Makefile.in (objfiles): Add linux.o instead of linuxdev.o. (MAKE): New variable. Used for the linux.o target. * configure.in: Add AC_CHECK_TOOL(MAKE, make). * i386/i386/spl.h: Include <i386/ipl.h>, for compatibility with OSF Mach 3.0. Suggested by Elgin Lee <ehl@funghi.com>. * linux/src: Renamed from linux/linux. * linux/dev: Renamed from linux/mach. * linux/Drivers.in (AC_INIT): Use dev/include/linux/autoconf.h, instead of mach/include/linux/autoconf.h. * Makefile.in (all): Target ../linux.o instead of ../linuxdev.o. * linux/dev/drivers/block/genhd.c: Include <machine/spl.h> instead of <i386/ipl.h>. * linux/dev/drivers/net/auto_irq.c: Remove unneeded header files, <i386/ipl.h> and <i386/pic.h>. * linux/dev/init/main.c: Many i386-dependent codes moved to ... * linux/dev/arch/i386/irq.c: ... here. * linux/dev/arch/i386/setup.c: New file. * linux/dev/arch/i386/linux_emul.h: Likewise. * linux/dev/arch/i386/glue/timer.c: Merged into sched.c. * linux/dev/arch/i386/glue/sched.c: Include <machine/spl.h> instead of <i386/ipl.h>, and moved to ... * linux/dev/kernel/sched.c: ... here. * linux/dev/arch/i386/glue/block.c: Include <machine/spl.h> and <linux_emul.h>, instead of i386-dependent header files, and moved to ... * linux/dev/glue/blocl.c: ... here. * linux/dev/arch/i386/glue/net.c: Include <machine/spl.h> and <linux_emul.h>, instead of i386-dependent header files, and moved to ... * linux/dev/glue/net.c: ... here. * linux/dev/arch/i386/glue/misc.c: Remove `x86' and moved to ... * linux/dev/glue/misc.c: ... here. * linux/dev/arch/i386/glue/kmem.c: Moved to ... * linux/dev/glue/kmem.c: ... here.
Diffstat (limited to 'linux/src/kernel/printk.c')
-rw-r--r--linux/src/kernel/printk.c253
1 files changed, 253 insertions, 0 deletions
diff --git a/linux/src/kernel/printk.c b/linux/src/kernel/printk.c
new file mode 100644
index 0000000..da8ffca
--- /dev/null
+++ b/linux/src/kernel/printk.c
@@ -0,0 +1,253 @@
+/*
+ * linux/kernel/printk.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * Modified to make sys_syslog() more flexible: added commands to
+ * return the last 4k of kernel messages, regardless of whether
+ * they've been read or not. Added option to suppress kernel printk's
+ * to the console. Added hook for sending the console messages
+ * elsewhere, in preparation for a serial line console (someday).
+ * Ted Ts'o, 2/11/93.
+ */
+
+#include <stdarg.h>
+
+#include <asm/segment.h>
+#include <asm/system.h>
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+
+#define LOG_BUF_LEN 8192
+
+static char buf[1024];
+
+extern void console_print(const char *);
+
+/* printk's without a loglevel use this.. */
+#define DEFAULT_MESSAGE_LOGLEVEL 4 /* KERN_WARNING */
+
+/* We show everything that is MORE important than this.. */
+#define MINIMUM_CONSOLE_LOGLEVEL 1 /* Minimum loglevel we let people use */
+#define DEFAULT_CONSOLE_LOGLEVEL 7 /* anything MORE serious than KERN_DEBUG */
+
+unsigned long log_size = 0;
+struct wait_queue * log_wait = NULL;
+int console_loglevel = DEFAULT_CONSOLE_LOGLEVEL;
+
+static void (*console_print_proc)(const char *) = 0;
+static char log_buf[LOG_BUF_LEN];
+static unsigned long log_start = 0;
+static unsigned long logged_chars = 0;
+
+/*
+ * Commands to sys_syslog:
+ *
+ * 0 -- Close the log. Currently a NOP.
+ * 1 -- Open the log. Currently a NOP.
+ * 2 -- Read from the log.
+ * 3 -- Read up to the last 4k of messages in the ring buffer.
+ * 4 -- Read and clear last 4k of messages in the ring buffer
+ * 5 -- Clear ring buffer.
+ * 6 -- Disable printk's to console
+ * 7 -- Enable printk's to console
+ * 8 -- Set level of messages printed to console
+ */
+asmlinkage int sys_syslog(int type, char * buf, int len)
+{
+ unsigned long i, j, count;
+ int do_clear = 0;
+ char c;
+ int error;
+
+ if ((type != 3) && !suser())
+ return -EPERM;
+ switch (type) {
+ case 0: /* Close log */
+ return 0;
+ case 1: /* Open log */
+ return 0;
+ case 2: /* Read from log */
+ if (!buf || len < 0)
+ return -EINVAL;
+ if (!len)
+ return 0;
+ error = verify_area(VERIFY_WRITE,buf,len);
+ if (error)
+ return error;
+ cli();
+ while (!log_size) {
+ if (current->signal & ~current->blocked) {
+ sti();
+ return -ERESTARTSYS;
+ }
+ interruptible_sleep_on(&log_wait);
+ }
+ i = 0;
+ while (log_size && i < len) {
+ c = *((char *) log_buf+log_start);
+ log_start++;
+ log_size--;
+ log_start &= LOG_BUF_LEN-1;
+ sti();
+ put_user(c,buf);
+ buf++;
+ i++;
+ cli();
+ }
+ sti();
+ return i;
+ case 4: /* Read/clear last kernel messages */
+ do_clear = 1;
+ /* FALL THRU */
+ case 3: /* Read last kernel messages */
+ if (!buf || len < 0)
+ return -EINVAL;
+ if (!len)
+ return 0;
+ error = verify_area(VERIFY_WRITE,buf,len);
+ if (error)
+ return error;
+ count = len;
+ if (count > LOG_BUF_LEN)
+ count = LOG_BUF_LEN;
+ if (count > logged_chars)
+ count = logged_chars;
+ j = log_start + log_size - count;
+ for (i = 0; i < count; i++) {
+ c = *((char *) log_buf+(j++ & (LOG_BUF_LEN-1)));
+ put_user(c, buf++);
+ }
+ if (do_clear)
+ logged_chars = 0;
+ return i;
+ case 5: /* Clear ring buffer */
+ logged_chars = 0;
+ return 0;
+ case 6: /* Disable logging to console */
+ console_loglevel = MINIMUM_CONSOLE_LOGLEVEL;
+ return 0;
+ case 7: /* Enable logging to console */
+ console_loglevel = DEFAULT_CONSOLE_LOGLEVEL;
+ return 0;
+ case 8:
+ if (len < 1 || len > 8)
+ return -EINVAL;
+ if (len < MINIMUM_CONSOLE_LOGLEVEL)
+ len = MINIMUM_CONSOLE_LOGLEVEL;
+ console_loglevel = len;
+ return 0;
+ }
+ return -EINVAL;
+}
+
+
+asmlinkage int printk(const char *fmt, ...)
+{
+ va_list args;
+ int i;
+ char *msg, *p, *buf_end;
+ static char msg_level = -1;
+ long flags;
+
+ save_flags(flags);
+ cli();
+ va_start(args, fmt);
+ i = vsprintf(buf + 3, fmt, args); /* hopefully i < sizeof(buf)-4 */
+ buf_end = buf + 3 + i;
+ va_end(args);
+ for (p = buf + 3; p < buf_end; p++) {
+ msg = p;
+ if (msg_level < 0) {
+ if (
+ p[0] != '<' ||
+ p[1] < '0' ||
+ p[1] > '7' ||
+ p[2] != '>'
+ ) {
+ p -= 3;
+ p[0] = '<';
+ p[1] = DEFAULT_MESSAGE_LOGLEVEL + '0';
+ p[2] = '>';
+ } else
+ msg += 3;
+ msg_level = p[1] - '0';
+ }
+ for (; p < buf_end; p++) {
+ log_buf[(log_start+log_size) & (LOG_BUF_LEN-1)] = *p;
+ if (log_size < LOG_BUF_LEN)
+ log_size++;
+ else {
+ log_start++;
+ log_start &= LOG_BUF_LEN-1;
+ }
+ logged_chars++;
+ if (*p == '\n')
+ break;
+ }
+ if (msg_level < console_loglevel && console_print_proc) {
+ char tmp = p[1];
+ p[1] = '\0';
+ (*console_print_proc)(msg);
+ p[1] = tmp;
+ }
+ if (*p == '\n')
+ msg_level = -1;
+ }
+ restore_flags(flags);
+ wake_up_interruptible(&log_wait);
+ return i;
+}
+
+/*
+ * The console driver calls this routine during kernel initialization
+ * to register the console printing procedure with printk() and to
+ * print any messages that were printed by the kernel before the
+ * console driver was initialized.
+ */
+void register_console(void (*proc)(const char *))
+{
+ int i,j;
+ int p = log_start;
+ char buf[16];
+ char msg_level = -1;
+ char *q;
+
+ console_print_proc = proc;
+
+ for (i=0,j=0; i < log_size; i++) {
+ buf[j++] = log_buf[p];
+ p++; p &= LOG_BUF_LEN-1;
+ if (buf[j-1] != '\n' && i < log_size - 1 && j < sizeof(buf)-1)
+ continue;
+ buf[j] = 0;
+ q = buf;
+ if (msg_level < 0) {
+ msg_level = buf[1] - '0';
+ q = buf + 3;
+ }
+ if (msg_level < console_loglevel)
+ (*proc)(q);
+ if (buf[j-1] == '\n')
+ msg_level = -1;
+ j = 0;
+ }
+}
+
+/*
+ * Write a message to a certain tty, not just the console. This is used for
+ * messages that need to be redirected to a specific tty.
+ * We don't put it into the syslog queue right now maybe in the future if
+ * really needed.
+ */
+void tty_write_message(struct tty_struct *tty, char *msg)
+{
+ if (tty && tty->driver.write)
+ tty->driver.write(tty, 0, msg, strlen(msg));
+ return;
+}