Re: [PATCH] Fix %x parsing in vsscanf()

[Deepak Saxena]

On Sep 23 2003, at 23:26, viro@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx was caught saying:
> The following, AFAICS, would be correct:
> 
>         if (*cp == '0') {
>                 cp++;
>                 if (unlikely((*cp == 'x' || *cp == 'X') && isxdigit(cp[1]))) {
>                         if (!base || base == 16) {
>                                 cp++;
>                                 base = 16;
>                         }
>                 } else if (!base)
>                         base = 8;
>         } else if (!base)
>                 base = 10;

We can remove everything but "base = 10;" from the second "else if"
clause b/c by this point we're guaranteed that it's not a hex or
octal value.

===== lib/vsprintf.c 1.16 vs edited =====
--- 1.16/lib/vsprintf.c	Sat Jul 12 12:49:57 2003
+++ edited/lib/vsprintf.c	Tue Sep 23 17:56:50 2003
@@ -32,16 +32,17 @@
 {
 	unsigned long result = 0,value;
 
-	if (!base) {
+	if (*cp == '0') {
+	       	cp++;
+	       	if (unlikely((*cp == 'x' || *cp == 'X') && isxdigit(cp[1]))) {
+		       	if (!base || base == 16) {
+			       	cp++;
+			       	base = 16;
+		       	}
+	       	} else if (!base)
+		       	base = 8;
+	} else if (!base) {
 		base = 10;
-		if (*cp == '0') {
-			base = 8;
-			cp++;
-			if ((*cp == 'x') && isxdigit(cp[1])) {
-				cp++;
-				base = 16;
-			}
-		}
 	}
 	while (isxdigit(*cp) &&
 	       (value = isdigit(*cp) ? *cp-'0' : toupper(*cp)-'A'+10) < base) {
@@ -76,16 +77,17 @@
 {
 	unsigned long long result = 0,value;
 
-	if (!base) {
+	if (*cp == '0') {
+	       	cp++;
+	       	if (unlikely((*cp == 'x' || *cp == 'X') && isxdigit(cp[1]))) {
+		       	if (!base || base == 16) {
+			       	cp++;
+			       	base = 16;
+		       	}
+	       	} else if (!base)
+		       	base = 8;
+	} else if (!base) {
 		base = 10;
-		if (*cp == '0') {
-			base = 8;
-			cp++;
-			if ((*cp == 'x') && isxdigit(cp[1])) {
-				cp++;
-				base = 16;
-			}
-		}
 	}
 	while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
 	    ? toupper(*cp) : *cp)-'A'+10) < base) {



-- 
Deepak Saxena
MontaVista Software - Powering the Embedded Revolution - www.mvista.com
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