From: Jarkko Hietaniemi <jhi@iki.fi>
Date: Mon, 7 Jul 2003 09:06:58 +0000 (+0000)
Subject: PerlIO_read() can return negative.
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=adac3afb577bf8dbdb46781b295def44cdc58b93;p=p5sagit%2Fp5-mst-13.2.git

PerlIO_read() can return negative.

p4raw-id: //depot/perl@20048
---

diff --git a/ext/Digest/MD5/MD5.xs b/ext/Digest/MD5/MD5.xs
index 0bf05f0..5c90f22 100644
--- a/ext/Digest/MD5/MD5.xs
+++ b/ext/Digest/MD5/MD5.xs
@@ -621,7 +621,7 @@ addfile(self, fh)
 	MD5_CTX* context = get_md5_ctx(self);
 	STRLEN fill = context->bytes_low & 0x3F;
 	unsigned char buffer[4096];
-	int  n;
+	SSize_t n;
     CODE:
 	if (fh) {
             if (fill) {
@@ -630,14 +630,19 @@ addfile(self, fh)
 	         * first.
 	         */
 	        STRLEN missing = 64 - fill;
-	        if ( (n = PerlIO_read(fh, buffer, missing)))
+	        n = PerlIO_read(fh, buffer, missing);
+		if (n >= 0)
 	 	    MD5Update(context, buffer, n);
-	        else
+	        else {
+		    if (PerlIO_error(fh)) {
+		        croak("Reading from filehandle failed");
+		    }
 		    XSRETURN(1);  /* self */
+		}
 	    }
 
 	    /* Process blocks until EOF or error */
-            while ( (n = PerlIO_read(fh, buffer, sizeof(buffer)))) {
+            while ( (n = PerlIO_read(fh, buffer, sizeof(buffer))) > 0 ) {
 	        MD5Update(context, buffer, n);
 	    }