From: Vegard Nossum <vegard.nossum@gmail•com>
To: Jan Engelhardt <jengelh@medozas•de>
Cc: linux-ia64@vger•kernel.org, Matthew Wilcox <matthew@wil•cx>,
linux-kernel@vger•kernel.org, linuxppc-dev@ozlabs•org,
Peter Anvin <hpa@zytor•com>,
Andrew Morton <akpm@linux-foundation•org>,
Linus Torvalds <torvalds@linux-foundation•org>,
"David S. Miller" <davem@davemloft•net>
Subject: Re: the printk problem
Date: Sat, 5 Jul 2008 14:52:31 +0200 [thread overview]
Message-ID: <20080705125230.GA20166@damson.getinternet.no> (raw)
In-Reply-To: <alpine.LNX.1.10.0807051332200.28765@fbirervta.pbzchgretzou.qr>
On Sat, Jul 5, 2008 at 1:33 PM, Jan Engelhardt <jengelh@medozas•de> wrote:
>
> On Saturday 2008-07-05 00:01, Andrew Morton wrote:
>>
>>We don't know how much interest there would be in churning NIPQUAD from
>>the net guys. Interestingly, there's also %C (wint_t) which is a
>>32-bit quantity. So we could just go and say "%C prints an ipv4
>>address" and be done with it. But there's no way of doing that for
>>ipv6 addresses so things would become asymmetrical there.
>
> struct in6_addr src;
> printk("Source address: %p{ipv6}\n", &src);
>
> How about %p{feature}?
Something like this?
(It's hard on the stack, yes, I know. We should fix kallsyms.)
Vegard
From: Vegard Nossum <vegard.nossum@gmail•com>
Date: Sat, 5 Jul 2008 14:01:00 +0200
Subject: [PATCH] printf: add %p{} extension
Signed-off-by: Vegard Nossum <vegard.nossum@gmail•com>
---
lib/vsprintf.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 44 insertions(+), 0 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 6021757..011cf3f 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -17,6 +17,7 @@
*/
#include <stdarg.h>
+#include <linux/kallsyms.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
@@ -366,6 +367,30 @@ static noinline char* put_dec(char *buf, unsigned long long num)
#define SMALL 32 /* Must be 32 == 0x20 */
#define SPECIAL 64 /* 0x */
+static char *custom_format(char *buf, char *end,
+ const char *fmt, unsigned int fmtlen, void *arg)
+{
+ if (!strncmp(fmt, "sym", fmtlen)) {
+ char name[KSYM_SYMBOL_LEN];
+ int len;
+ int i;
+
+ len = sprint_symbol(name, (unsigned long) arg);
+ if (len < 0)
+ return buf;
+
+ i = 0;
+ while (i < len) {
+ if (buf < end)
+ *buf = name[i];
+ ++buf;
+ ++i;
+ }
+ }
+
+ return buf;
+}
+
static char *number(char *buf, char *end, unsigned long long num, int base, int size, int precision, int type)
{
/* we are called with base 8, 10 or 16, only, thus don't need "G..." */
@@ -648,6 +673,25 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
continue;
case 'p':
+ if (fmt[1] == '{') {
+ const char *cfmt;
+
+ /* Skip the '%{' */
+ ++fmt;
+ ++fmt;
+
+ cfmt = fmt;
+
+ /* Skip everything up to the '}' */
+ while (*fmt && *fmt != '}')
+ ++fmt;
+
+ str = custom_format(str, end,
+ cfmt, fmt - cfmt,
+ va_arg(args, void *));
+ continue;
+ }
+
flags |= SMALL;
if (field_width == -1) {
field_width = 2*sizeof(void *);
--
1.5.4.1
next prev parent reply other threads:[~2008-07-05 12:52 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20080625131101.GA6205@digi.com>
[not found] ` <20080704104634.GA31634@digi.com>
[not found] ` <20080704111540.ddffd241.akpm@linux-foundation.org>
[not found] ` <alpine.LFD.1.10.0807041147450.2815@woody.linux-foundation.org>
2008-07-04 20:02 ` the printk problem Linus Torvalds
2008-07-04 20:27 ` Andrew Morton
2008-07-04 20:41 ` Linus Torvalds
2008-07-04 20:42 ` Matthew Wilcox
2008-07-04 22:01 ` Andrew Morton
2008-07-05 2:03 ` Matthew Wilcox
2008-07-22 10:05 ` [PATCH] Make u64 long long on all architectures (was: the printk problem) Andrew Morton
2008-07-22 10:36 ` Michael Ellerman
2008-07-22 10:53 ` Andrew Morton
2008-07-22 11:36 ` Benjamin Herrenschmidt
2008-07-22 11:35 ` Benjamin Herrenschmidt
2008-07-05 10:20 ` the printk problem Denys Vlasenko
2008-07-05 11:33 ` Jan Engelhardt
2008-07-05 12:52 ` Vegard Nossum [this message]
2008-07-05 13:24 ` Jan Engelhardt
2008-07-05 13:50 ` Vegard Nossum
2008-07-05 14:07 ` Jan Engelhardt
2008-07-05 17:56 ` Linus Torvalds
2008-07-05 18:40 ` Jan Engelhardt
2008-07-05 18:44 ` Linus Torvalds
2008-07-05 18:41 ` Vegard Nossum
2008-07-05 18:52 ` Matthew Wilcox
2008-07-06 0:02 ` Pekka Enberg
2008-07-06 5:17 ` Randy Dunlap
2008-07-04 22:58 ` Benjamin Herrenschmidt
2008-07-04 20:36 ` Matthew Wilcox
2008-07-08 1:44 ` Kyle McMartin
2008-07-04 23:00 ` Benjamin Herrenschmidt
2008-07-04 23:25 ` Linus Torvalds
2008-07-05 22:32 ` Linus Torvalds
2008-07-05 22:57 ` Arjan van de Ven
2008-07-06 5:27 ` Ingo Molnar
2008-07-06 5:37 ` Linus Torvalds
2008-07-06 5:53 ` Ingo Molnar
2008-07-06 6:13 ` Ingo Molnar
2008-07-07 1:14 ` Benjamin Herrenschmidt
2008-07-07 3:26 ` Stephen Rothwell
2008-07-07 3:28 ` Michael Ellerman
2008-07-07 4:59 ` Stephen Rothwell
2008-07-07 3:43 ` Benjamin Herrenschmidt
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