X-Git-Url: http://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Fopt%2Fhelpers.c;h=118e543602e06b981e6faee7dd5f416cf819d5cd;hb=33ba12adf082b9432ae0471b6bb742cde14254ed;hp=43b86d7ca2ad953665522cf37f449b8046ffd3b7;hpb=7220240c0e2fa8c9610736565e73d3c74a73466c;p=ccan

diff --git a/ccan/opt/helpers.c b/ccan/opt/helpers.c
index 43b86d7c..118e5436 100644
--- a/ccan/opt/helpers.c
+++ b/ccan/opt/helpers.c
@@ -9,14 +9,14 @@
 #include <stdio.h>
 #include <limits.h>
 #include "private.h"
+#include <float.h>
 
 /* Upper bound to sprintf this simple type?  Each 3 bits < 1 digit. */
 #define CHAR_SIZE(type) (((sizeof(type)*CHAR_BIT + 2) / 3) + 1)
 
-/* FIXME: asprintf module? */
 static char *arg_bad(const char *fmt, const char *arg)
 {
-	char *str = malloc(strlen(fmt) + strlen(arg));
+	char *str = opt_alloc.alloc(strlen(fmt) + strlen(arg));
 	sprintf(str, fmt, arg);
 	return str;
 }
@@ -126,8 +126,14 @@ char *opt_set_floatval(const char *arg, float *f)
 		return err;
 
 	*f = d;
-	if (*f != d)
-		return arg_bad("'%s' is out of range", arg);
+
+	/*allow true infinity via --foo=INF, while avoiding isinf() from math.h
+	  because it wasn't standard 25 years ago.*/
+	double inf = 1e300 * 1e300; /*direct 1e600 annoys -Woverflow*/
+	if ((d > FLT_MAX || d < -FLT_MAX) && d != inf && d != -inf)
+		return arg_bad("'%s' is out of range for a 32 bit float", arg);
+	if (d != 0 && *f == 0)
+		return arg_bad("'%s' is out of range (truncated to zero)", arg);
 
 	return NULL;
 }