Always fill in a NULL for a zero-length char string or octet string in

asn1_remove_charstring or asn1_remove_octetstring.  This means we do
the same thing no matter whether the system returns NULL for malloc(0) or not.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@4376 dc483132-0cff-0310-8789-dd5450dbe970

2 files changed, 20 insertions, 3 deletions

diff --git a/src/lib/krb5/asn.1/ChangeLog b/src/lib/krb5/asn.1/ChangeLog
index 139d5bfbd..d4883a35e 100644
--- a/src/lib/krb5/asn.1/ChangeLog
+++ b/src/lib/krb5/asn.1/ChangeLog
@@ -1,3 +1,11 @@
+Thu Sep 29 14:26:34 1994  Theodore Y. Ts'o  (tytso@dcl)
+
+	* asn1buf.c (asn1buf_remove_octetstring, asn1buf_remove_charstring): 
+		If the length is zero, don't call calloc(0,1); instead
+		return a NULL pointer.  This way, we get consistent
+		behavior even on systems where malloc(0) returns a
+		non-null pointer.
+
 Tue Sep 27 23:31:50 1994  Theodore Y. Ts'o  (tytso@dcl)
 
 	* krb5_encode.c (encode_krb5_enc_kdc_rep_part): = should have been
diff --git a/src/lib/krb5/asn.1/asn1buf.c b/src/lib/krb5/asn.1/asn1buf.c
index 393014ddd..81c7df309 100644
--- a/src/lib/krb5/asn.1/asn1buf.c
+++ b/src/lib/krb5/asn.1/asn1buf.c
@@ -173,8 +173,13 @@ asn1_error_code asn1buf_remove_octetstring(DECLARG(asn1buf *, buf),
   int i;
 
   if(buf->next + len - 1 > buf->bound) return ASN1_OVERRUN;
+  if (len == 0) {
+      *s = 0;
+      return 0;
+  }
   *s = (asn1_octet*)calloc(len,sizeof(asn1_octet));
-  if((*s == NULL) && len) return ENOMEM;
+  if (*s == NULL)
+      return ENOMEM;
   for(i=0; i<len; i++)
     (*s)[i] = (asn1_octet)(buf->next)[i];
   buf->next += len;
@@ -190,9 +195,13 @@ asn1_error_code asn1buf_remove_charstring(DECLARG(asn1buf *, buf),
 {
   int i;
 
-  if(buf->next + len - 1 > buf->bound) return ASN1_OVERRUN;
+  if (buf->next + len - 1 > buf->bound) return ASN1_OVERRUN;
+  if (len == 0) {
+      *s = 0;
+      return 0;
+  }
   *s = (char*)calloc(len,sizeof(char));
-  if((*s == NULL) && len) return ENOMEM;
+  if (*s == NULL) return ENOMEM;
   for(i=0; i<len; i++)
     (*s)[i] = (char)(buf->next)[i];
   buf->next += len;