iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[PATCH] printk return value: fix it

Browse Source 
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
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
kernel/printk.c
View File

@ -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] != '>') {
@ -592,9 +592,9 @@ asmlinkage int vprintk(const char *fmt, va_list args)
emit_log_char(default_message_loglevel
+ '0');
emit_log_char('>');
}
printed_len += 3;
}
}
log_level_unknown = 0;
if (!*p)
break;