2009-11-04 14:48:27

by André Goddard Rosa

[permalink] [raw]
Subject: [PATCH v3 1/7] vsprintf: factorize "(null)" string

From: Andr? Goddard Rosa <[email protected]>
Date: Tue, 3 Nov 2009 11:07:21 -0200
Subject: [PATCH v3 1/7] vsprintf: factorize "(null)" string
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Change "<NULL>" to "(null)" and make it a static const char[] hoping that
the compiler will make null_str a label to a read-only area containing it.

See:
http://people.redhat.com/drepper/dsohowto.pdf part 2.4.2
http://udrepper.livejournal.com/13851.html
http://udrepper.livejournal.com/15119.html

Signed-off-by: Andr? Goddard Rosa <[email protected]>
Acked-by: Frederic Weisbecker <[email protected]>
---
lib/vsprintf.c | 10 ++++++----
1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 33bed5e..002f462 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -34,6 +34,8 @@
/* Works only for digits and letters, but small and fast */
#define TOLOWER(x) ((x) | 0x20)

+static const char null_str[] = "(null)";
+
static unsigned int simple_guess_base(const char *cp)
{
if (cp[0] == '0') {
@@ -546,12 +548,12 @@ static char *number(char *buf, char *end,
unsigned long long num,
return buf;
}

-static char *string(char *buf, char *end, char *s, struct printf_spec spec)
+static char *string(char *buf, char *end, const char *s, struct
printf_spec spec)
{
int len, i;

if ((unsigned long)s < PAGE_SIZE)
- s = "<NULL>";
+ s = null_str;

len = strnlen(s, spec.precision);

@@ -822,7 +824,7 @@ static char *pointer(const char *fmt, char *buf,
char *end, void *ptr,
struct printf_spec spec)
{
if (!ptr)
- return string(buf, end, "(null)", spec);
+ return string(buf, end, null_str, spec);

switch (*fmt) {
case 'F':
@@ -1445,7 +1447,7 @@ do { \
size_t len;
if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
|| (unsigned long)save_str < PAGE_SIZE)
- save_str = "<NULL>";
+ save_str = null_str;
len = strlen(save_str);
if (str + len + 1 < end)
memcpy(str, save_str, len + 1);
--
1.6.5.2.143.g8cc62.dirty


2009-11-08 11:02:46

by Ingo Molnar

[permalink] [raw]
Subject: Re: [PATCH v3 1/7] vsprintf: factorize "(null)" string


* Andr? Goddard Rosa <[email protected]> wrote:

> @@ -546,12 +548,12 @@ static char *number(char *buf, char *end,
> unsigned long long num,
> return buf;
> }
>
> -static char *string(char *buf, char *end, char *s, struct printf_spec spec)
> +static char *string(char *buf, char *end, const char *s, struct
> printf_spec spec)

FYI, your patches have such linewraps, so the patches wont apply:

patch: **** malformed patch at line 47: unsigned long long num,

See Documentation/email-clients.txt about how to send patches without
such problems.

Mind resending with this fixed?

Also, this RFC patch of yours:

vsprintf: reuse almost identical simple_strtoulX() functions

looks nice too IMO - mind including it in your series?

Thanks,

Ingo

2009-11-08 15:36:47

by André Goddard Rosa

[permalink] [raw]
Subject: Re: [PATCH v3 1/7] vsprintf: factorize "(null)" string

Hi, Ingo!

On Sun, Nov 8, 2009 at 9:02 AM, Ingo Molnar <[email protected]> wrote:
>
> * Andr? Goddard Rosa <[email protected]> wrote:
>
>> @@ -546,12 +548,12 @@ static char *number(char *buf, char *end,
>> unsigned long long num,
>> ? ? ? return buf;
>> ?}
>>
>> -static char *string(char *buf, char *end, char *s, struct printf_spec spec)
>> +static char *string(char *buf, char *end, const char *s, struct
>> printf_spec spec)
>
> FYI, your patches have such linewraps, so the patches wont apply:
>
> ?patch: **** malformed patch at line 47: unsigned long long num,
>
> See Documentation/email-clients.txt about how to send patches without
> such problems.
>
> Mind resending with this fixed?

I tried to fix these by using send-email this time. Please let me know
if you still see any issue.

> Also, this RFC patch of yours:
>
> ?vsprintf: reuse almost identical simple_strtoulX() functions
>
> looks nice too IMO - mind including it in your series?

Can I consider it as an Acked-by? ;-)

Just sent v4 now.

Thank you,
Andr?