[-mm PATCH 1/2] printk return value: fix it

[Guillaume Chazarain <guichaz@yahoo.fr>]

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What's the true meaning of the printk return value?
Should it include the priority prefix length of 3? and what about the timing
information? In both cases it was broken:

strace -e write echo 1 > /dev/kmsg
=> write(1, "1\n", 2)                      = 5
strace -e write echo "<1>1" > /dev/kmsg
=> write(1, "<1>1\n", 5)                   = 8

The returned length was "length of input string + 3", I made it "length
of string output to the log buffer".

Note that I couldn't find any printk caller in the kernel interested by its 
return value besides kmsg_write.

Signed-off-by: Guillaume Chazarain <guichaz@yahoo.fr>
Acked-By: Tim Bird <tim.bird@am.sony.com>

---
  printk.c |    6 +++---
  1 files changed, 3 insertions(+), 3 deletions(-)



-- 
Guillaume



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diff -r d18e06f9c571 kernel/printk.c
--- a/kernel/printk.c	Mon Nov 14 10:22:49 2005 +0800
+++ b/kernel/printk.c	Mon Nov 14 15:02:56 2005 +0100
@@ -569,7 +569,7 @@
 				   p[1] <= '7' && p[2] == '>') {
 					loglev_char = p[1];
 					p += 3;
-					printed_len += 3;
+					printed_len -= 3;
 				} else {
 					loglev_char = default_message_loglevel
 						+ '0';
@@ -584,7 +584,7 @@
 
 				for (tp = tbuf; tp < tbuf + tlen; tp++)
 					emit_log_char(*tp);
-				printed_len += tlen - 3;
+				printed_len += tlen;
 			} else {
 				if (p[0] != '<' || p[1] < '0' ||
 				   p[1] > '7' || p[2] != '>') {
@@ -592,8 +592,8 @@
 					emit_log_char(default_message_loglevel
 						+ '0');
 					emit_log_char('>');
+					printed_len += 3;
 				}
-				printed_len += 3;
 			}
 			log_level_unknown = 0;
 			if (!*p)