buffer size changed from size_t to int (it is always small) +

comments + assert that printf result fits in given buffer
This commit is contained in:
Roberto Ierusalimschy 2015-06-24 15:25:10 -03:00
parent cb1e451999
commit 5aabb7a891

View File

@ -1,5 +1,5 @@
/*
** $Id: lstrlib.c,v 1.229 2015/05/20 17:39:23 roberto Exp roberto $
** $Id: lstrlib.c,v 1.230 2015/06/18 14:26:05 roberto Exp roberto $
** Standard library for string operations and pattern-matching
** See Copyright Notice in lua.h
*/
@ -830,7 +830,7 @@ static lua_Number adddigit (char *buff, int n, lua_Number x) {
}
static int num2straux (char *buff, size_t sz, lua_Number x) {
static int num2straux (char *buff, int sz, lua_Number x) {
if (x != x || x == HUGE_VAL || x == -HUGE_VAL) /* inf or NaN? */
return l_sprintf(buff, sz, LUA_NUMBER_FMT, x); /* equal to '%g' */
else if (x == 0) { /* can be -0... */
@ -856,13 +856,13 @@ static int num2straux (char *buff, size_t sz, lua_Number x) {
} while (m > 0);
}
n += l_sprintf(buff + n, sz - n, "p%+d", e); /* add exponent */
lua_assert((size_t)n < sz);
lua_assert(n < sz);
return n;
}
}
static int lua_number2strx (lua_State *L, char *buff, size_t sz,
static int lua_number2strx (lua_State *L, char *buff, int sz,
const char *fmt, lua_Number x) {
int n = num2straux(buff, sz, x);
if (fmt[SIZELENMOD] == 'A') {
@ -880,8 +880,10 @@ static int lua_number2strx (lua_State *L, char *buff, size_t sz,
/*
** Maximum size of each formatted item. This maximum size is produced
** by format('%.99f', minfloat), and is equal to 99 + 2 ('-' and '.') +
** number of decimal digits to represent minfloat.
** by format('%.99f', -maxfloat), and is equal to 99 + 3 ('-', '.',
** and '\0') + number of decimal digits to represent maxfloat (which
** is maximum exponent + 1). (99+3+1 then rounded to 120 for "extra
** expenses", such as locale-dependent stuff)
*/
#define MAX_ITEM (120 + l_mathlim(MAX_10_EXP))
@ -1020,6 +1022,7 @@ static int str_format (lua_State *L) {
*(strfrmt - 1));
}
}
lua_assert(nb < MAX_ITEM);
luaL_addsize(&b, nb);
}
}