commit 5aabb7a89172b74097faa8f34a6a6520d839bde6
parent cb1e451999cfed49a66859d8189a684839845e7f
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Wed, 24 Jun 2015 15:24:45 -0300
buffer size changed from size_t to int (it is always small) +
comments + assert that printf result fits in given buffer
Diffstat:
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/lstrlib.c b/lstrlib.c
@@ -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') {
@@ -880,10 +880,12 @@ 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))
+#define MAX_ITEM (120 + l_mathlim(MAX_10_EXP))
/* valid flags in a format specification */
@@ -1020,6 +1022,7 @@ static int str_format (lua_State *L) {
*(strfrmt - 1));
}
}
+ lua_assert(nb < MAX_ITEM);
luaL_addsize(&b, nb);
}
}