From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Petr Mladek <pmladek@suse.com>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
linux-kernel@vger.kernel.org,
Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Steven Rostedt <rostedt@goodmis.org>
Subject: [PATCH v2 1/3] lib/vsprintf: Replace hidden BUILD_BUG_ON() with static_assert()
Date: Fri, 31 Jul 2020 21:08:22 +0300 [thread overview]
Message-ID: <20200731180825.30575-1-andriy.shevchenko@linux.intel.com> (raw)
First of all, there is no compile time check for the SMALL
to be ' ' (0x20, i.e. space). Second, for ZEROPAD the check
is hidden in the code.
For better maintenance replace BUILD_BUG_ON() with static_assert()
for ZEROPAD and move it closer to the definition. While at it,
introduce check for SMALL.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
v2: replaced to have plain defined constant on left side, added tag (Steven)
lib/vsprintf.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 31a674dd2674..f90f09682977 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -381,6 +381,9 @@ int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
+static_assert(ZEROPAD == ('0' - ' '));
+static_assert(SMALL == ' ');
+
enum format_type {
FORMAT_TYPE_NONE, /* Just a string part */
FORMAT_TYPE_WIDTH,
@@ -507,7 +510,7 @@ char *number(char *buf, char *end, unsigned long long num,
/* zero or space padding */
if (!(spec.flags & LEFT)) {
char c = ' ' + (spec.flags & ZEROPAD);
- BUILD_BUG_ON(' ' + ZEROPAD != '0');
+
while (--field_width >= 0) {
if (buf < end)
*buf = c;
--
2.27.0
next reply other threads:[~2020-07-31 18:08 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-31 18:08 Andy Shevchenko [this message]
2020-07-31 18:08 ` [PATCH v2 2/3] lib/vsprintf: Replace custom spec to print decimals with generic one Andy Shevchenko
2020-07-31 18:18 ` Andy Shevchenko
2020-07-31 18:20 ` Joe Perches
2020-07-31 20:48 ` Steven Rostedt
2020-08-01 1:42 ` Sergey Senozhatsky
2020-08-01 1:40 ` Sergey Senozhatsky
2020-07-31 18:08 ` [PATCH v2 3/3] lib/vsprintf: Force type of flags value for gfp_t Andy Shevchenko
2020-07-31 20:49 ` Steven Rostedt
2020-08-01 1:36 ` Sergey Senozhatsky
2020-08-01 1:39 ` [PATCH v2 1/3] lib/vsprintf: Replace hidden BUILD_BUG_ON() with static_assert() Sergey Senozhatsky
2020-08-01 4:46 ` Sergey Senozhatsky
2020-08-04 8:34 ` Petr Mladek
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