From cf3a796dd1dfe53f7d67507f7f4d5c05cc7ebc8d Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Wed, 26 Jul 2017 14:38:19 +0200 Subject: ash: alloc slightly smaller buffer in cvtnum(); faster unsetvar() Signed-off-by: Denys Vlasenko --- shell/ash.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) (limited to 'shell') diff --git a/shell/ash.c b/shell/ash.c index 524580e8a..915e86167 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" */ + if (sizeof(arith_t) < 4) len += 2; + + expdest = makestrspace(len, expdest); + len = fmtstr(expdest, len, ARITH_FMT, num); STADJUST(len, expdest); return len; } -- cgit v1.2.3