40076 - fix signed vs unsigned comparison in nsXMLMIMEDataSource.cpp

Status: VERIFIED FIXED

(Core :: Networking, defect, P3)

Description

[David Avery]

cvs blamed listing

352 davidm 1.6                  PRUint32 count;
353 davidm 1.1                  rv = info->GetFileExtensions(& count,
&extensions );
354                             if ( NS_FAILED ( rv ) )
355                                     return rv;
356                             buffer+=kExtensions;
357                             buffer+="=\"";
358   for ( PRInt32 i = 0; i<(count-1); i++ )

patch:
diff -u -r1.11 nsXMLMIMEDataSource.cpp
--- nsXMLMIMEDataSource.cpp	2000/05/17 00:05:52	1.11
+++ nsXMLMIMEDataSource.cpp	2000/05/22 01:24:40
@@ -355,7 +355,7 @@
 			return rv;
 		buffer+=kExtensions;
 		buffer+="=\"";
-		for ( PRInt32 i = 0; i<(count-1); i++ )
+		for ( PRUInt32 i = 0; i<(count-1); i++ )
 		{
 			buffer+=extensions[i];
 			buffer+=",";

Comment 1

[davidm]

Can count be 0? Probably be better to convert count to a signed integer. M20

Comment 2

[David Avery]

since extensions[] can't have a negitive subscript PRUint32 makes more sense to
me

Comment 3

[davidm]

Sure but then you can't do the -1 math since (0-1) is a really big number. 
Unsigned really doesn't prevent negative numbers. It just converts negative 
numbers into really big postive ones which almost never what you want.  See Lare 
Scale c++ for why they are so evil in interfaces. 

Comment 4

[Dawn Endico]

David has left netscape and [e-mail] is an invalid email address.
Assigning his five remaining bugs to gagan to find a new owner for them. Thanks

Comment 5

[Dawn Endico]

oops i didn't actually reassign to gagan last time. sorry for the spam

Comment 6

[Gagan]

->gordon

Comment 7

[johng]

triage team:
nsbeta3- because we don't think we run into this very often.  Marking [next
version] to indicate that we will check this in for next version, just didn't
make this train (bigger fish to fry).

Comment 8

[benc]

mass move, v2.
qa to me.

Comment 9

[gordon]

It looks like this was fixed back in February, 2002, by [e-mail] as
part of bug 68801.

Comment 10

[benc]

VERIFIED:
http://lxr.mozilla.org/mozilla/source/netwerk/mime/src/nsXMLMIMEDataSource.cpp#375