Java: Fix gcjh JNI bug

[Bryce McKinlay <bryce at waitaki dot otago dot ac dot nz>]

"gcjh -jni" now looks at superclasses in order to determine if a given 
class is a throwable. Unfortunatly if it tried to do this for any class 
which did not directly extend throwable it would give an error like:

"couldn't find class `ava.lang.Object'."

Because it was calling itself with a classname extracted from the super 
field of a classfile while it expected the class name as a signature 
fragment (ie with a leading 'L'), and so was stripping the first 
character. In addition the super class name obtained directly from the 
classfile data is not null terminated, so we must copy it into a 
null-terminated string before recursing.

This patch fixes, ok to commit?

regards

Bryce.

2002-05-30  Bryce McKinlay  <bryce@waitaki.otago.ac.nz>

	* gjavah.c (throwable_p): Accept argument as either a classname or 
	signature fragment. Create null-terminated classname string for super
	when calling itself recursively.
	(decode_signature_piece): Skip first character from class name 
	signature when calling throwable_p.

Index: gjavah.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/java/gjavah.c,v
retrieving revision 1.89
diff -u -r1.89 gjavah.c
--- gjavah.c	19 May 2002 16:25:51 -0000	1.89
+++ gjavah.c	30 May 2002 06:41:35 -0000
@@ -1104,11 +1104,12 @@
   return ! strcmp ((char *) p1, (char *) p2);
 }
 
-/* Return 1 if the initial (L<classname>;) part of SIGNATURE names a
-   subclass of throwable, or 0 if not.  */
+/* Return 1 if the initial part of CLNAME names a subclass of throwable, 
+   or 0 if not.  CLNAME may be extracted from a signature, and can be 
+   terminated with either `;' or NULL.  */
 static int
-throwable_p (signature)
-     const unsigned char *signature;
+throwable_p (clname)
+     const unsigned char *clname;
 {
   int length;
   unsigned char *current;
@@ -1148,12 +1149,12 @@
       init_done = 1;
     }
 
-  for (length = 0; signature[length] != ';'; ++length)
+  for (length = 0; clname[length] != ';' && clname[length] != '\0'; ++length)
     ;
   current = (unsigned char *) ALLOC (length);
-  for (i = 1; signature[i] != ';'; ++i)
-    current[i - 1] = signature[i] == '/' ? '.' : signature[i];
-  current[i - 1] = '\0';
+  for (i = 0; i < length; ++i)
+    current[i] = clname[i] == '/' ? '.' : clname[i];
+  current[length] = '\0';
 
   /* We don't compute the hash slot here because the table might be
      modified by the recursion.  In that case the slot could be
@@ -1166,6 +1167,8 @@
     {
       JCF jcf;
       PTR *slot;
+      unsigned char *super, *tmp;
+      int super_length = -1;
       const char *classfile_name = find_class (current, strlen (current),
 					       &jcf, 0);
 
@@ -1185,7 +1188,12 @@
 	}
       jcf_parse_class (&jcf);
 
-      result = throwable_p (super_class_name (&jcf, NULL));
+      tmp = (unsigned char *) super_class_name (&jcf, &super_length);
+      super = (unsigned char *) ALLOC (super_length + 1);
+      memcpy (super, tmp, super_length);      
+      super[super_length] = '\0';
+
+      result = throwable_p (super);
       slot = htab_find_slot (result ? throw_hash : non_throw_hash,
 			     current, INSERT);
       *slot = current;
@@ -1317,7 +1325,8 @@
 	  else if (! strncmp (signature, "Ljava/lang/Class;",
 			      sizeof ("Ljava/lang/Class;") - 1))
 	    ctype = "jclass";
-	  else if (throwable_p (signature))
+	  /* Skip leading 'L' for throwable_p call.  */
+	  else if (throwable_p (signature + 1))
 	    ctype = "jthrowable";
 	  else
 	    ctype = "jobject";