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authorDenys Vlasenko2017-07-26 14:38:19 +0200
committerDenys Vlasenko2017-07-26 14:38:19 +0200
commitcf3a796dd1dfe53f7d67507f7f4d5c05cc7ebc8d (patch)
treeefdfacffd404ba36ebd19ecff069768896235570
parentb31b61bb9bff8a920b7e25b83e3aa08f7c907331 (diff)
downloadbusybox-cf3a796dd1dfe53f7d67507f7f4d5c05cc7ebc8d.zip
busybox-cf3a796dd1dfe53f7d67507f7f4d5c05cc7ebc8d.tar.gz
ash: alloc slightly smaller buffer in cvtnum(); faster unsetvar()
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r--shell/ash.c22
1 files changed, 13 insertions, 9 deletions
diff --git a/shell/ash.c b/shell/ash.c
index 524580e..915e861 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -214,6 +214,9 @@
#include "shell_common.h"
#if ENABLE_FEATURE_SH_MATH
# include "math.h"
+#else
+typedef long arith_t;
+# define ARITH_FMT "%ld"
#endif
#if ENABLE_ASH_RANDOM_SUPPORT
# include "random.h"
@@ -621,8 +624,8 @@ fmtstr(char *outbuf, size_t length, const char *fmt, ...)
va_list ap;
int ret;
- va_start(ap, fmt);
INT_OFF;
+ va_start(ap, fmt);
ret = vsnprintf(outbuf, length, fmt, ap);
va_end(ap);
INT_ON;
@@ -2345,7 +2348,7 @@ setvar0(const char *name, const char *val)
static void
unsetvar(const char *s)
{
- setvar0(s, NULL);
+ setvar(s, NULL, 0);
}
/*
@@ -5697,19 +5700,20 @@ static struct arglist exparg;
/*
* Our own itoa().
+ * cvtnum() is used even if math support is off (to prepare $? values and such).
*/
-#if !ENABLE_FEATURE_SH_MATH
-/* cvtnum() is used even if math support is off (to prepare $? values and such) */
-typedef long arith_t;
-# define ARITH_FMT "%ld"
-#endif
static int
cvtnum(arith_t num)
{
int len;
- expdest = makestrspace(sizeof(arith_t)*3 + 2, expdest);
- len = fmtstr(expdest, sizeof(arith_t)*3 + 2, ARITH_FMT, num);
+ /* 32-bit and wider ints require buffer size of bytes*3 (or less) */
+ len = sizeof(arith_t) * 3;
+ /* If narrower: worst case, 1-byte ints: need 5 bytes: "-127<NUL>" */
+ if (sizeof(arith_t) < 4) len += 2;
+
+ expdest = makestrspace(len, expdest);
+ len = fmtstr(expdest, len, ARITH_FMT, num);
STADJUST(len, expdest);
return len;
}