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[PATCH] printk return value: fix it

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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>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Guillaume Chazarain 2006-01-08 01:02:41 -08:00 committed by Linus Torvalds
parent 2520f14ca8
commit 025510cd20
1 changed files with 3 additions and 3 deletions
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6
kernel/printk.c
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@ -569,7 +569,7 @@ asmlinkage int vprintk(const char *fmt, va_list args)
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 @@ asmlinkage int vprintk(const char *fmt, va_list args)
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 @@ asmlinkage int vprintk(const char *fmt, va_list args)
emit_log_char(default_message_loglevel
+ '0');
emit_log_char('>');
printed_len += 3;
}
printed_len += 3;
}
log_level_unknown = 0;
if (!*p)