From 9100e797f839e5a231fa29d2d05a29cf4f4eb4f8 Mon Sep 17 00:00:00 2001
From: Vitor Santos Costa <vsc@dcc.fc.up.pt>
Date: Wed, 8 Nov 2017 10:26:51 +0100
Subject: [PATCH] opaque terms

---
 C/bignum.c      | 10 +++++-----
 C/c_interface.c | 16 +++++++++-------
 H/TermExt.h     |  8 ++++----
 3 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/C/bignum.c b/C/bignum.c
index 9da08c0a6..b9a3a46ef 100644
--- a/C/bignum.c
+++ b/C/bignum.c
@@ -167,7 +167,7 @@ int Yap_CleanOpaqueVariable(CELL d) {
               "clean opaque: bad blob with tag " UInt_FORMAT, blob_tag);
     return FALSE;
   }
-  blob_info = blob_tag - USER_BLOB_START;
+  blob_info = blob_tag;
   if (!GLOBAL_OpaqueHandlers)
     return false;
   if (!GLOBAL_OpaqueHandlers[blob_info].fail_handler)
@@ -192,7 +192,7 @@ YAP_Opaque_CallOnWrite Yap_blob_write_handler(Term t) {
               "clean opaque: bad blob with tag " UInt_FORMAT, blob_tag);
     return FALSE;
   }
-  blob_info = blob_tag - USER_BLOB_START;
+  blob_info = blob_tag;
   if (!GLOBAL_OpaqueHandlers) {
     return NULL;
   }
@@ -214,7 +214,7 @@ YAP_Opaque_CallOnGCMark Yap_blob_gc_mark_handler(Term t) {
   if (blob_tag < USER_BLOB_START || blob_tag >= USER_BLOB_END) {
     return NULL;
   }
-  blob_info = blob_tag - USER_BLOB_START;
+  blob_info = blob_tag;
   if (!GLOBAL_OpaqueHandlers)
     return NULL;
   return GLOBAL_OpaqueHandlers[blob_info].mark_handler;
@@ -237,7 +237,7 @@ YAP_Opaque_CallOnGCRelocate Yap_blob_gc_relocate_handler(Term t) {
               "clean opaque: bad blob with tag " UInt_FORMAT, blob_tag);
     return FALSE;
   }
-  blob_info = blob_tag - USER_BLOB_START;
+  blob_info = blob_tag;
   if (!GLOBAL_OpaqueHandlers)
     return NULL;
   return GLOBAL_OpaqueHandlers[blob_info].relocate_handler;
@@ -509,4 +509,4 @@ void Yap_InitBigNums(void) {
   Yap_InitCPred("string", 1, p_is_string, SafePredFlag);
   Yap_InitCPred("opaque", 1, p_is_opaque, SafePredFlag);
   Yap_InitCPred("nb_set_bit", 2, p_nb_set_bit, SafePredFlag);
-}
\ No newline at end of file
+}
diff --git a/C/c_interface.c b/C/c_interface.c
index 22c0e2043..c0f03a315 100755
--- a/C/c_interface.c
+++ b/C/c_interface.c
@@ -1893,34 +1893,36 @@ X_API void *YAP_ExternalDataInStackFromTerm(Term t) {
 
 X_API YAP_opaque_tag_t YAP_NewOpaqueType(struct YAP_opaque_handler_struct *f) {
     int i;
-    if (!GLOBAL_OpaqueHandlers) {
+    if (!GLOBAL_OpaqueHandlersCount) {
         GLOBAL_OpaqueHandlers =
-                malloc(sizeof(YAP_opaque_handler_t) * (USER_BLOB_END - USER_BLOB_START));
+                malloc(sizeof(YAP_opaque_handler_t) *USER_BLOB_END );
         if (!GLOBAL_OpaqueHandlers) {
             /* no room */
             return -1;
         }
-    } else if (GLOBAL_OpaqueHandlersCount == USER_BLOB_END - USER_BLOB_START) {
+	GLOBAL_OpaqueHandlersCount = USER_BLOB_START;
+    } else if (GLOBAL_OpaqueHandlersCount == USER_BLOB_END) {
         /* all types used */
         return -1;
     }
     i = GLOBAL_OpaqueHandlersCount++;
     memcpy(GLOBAL_OpaqueHandlers + i, f, sizeof(YAP_opaque_handler_t));
-    return i + USER_BLOB_START;
+    return i;
 }
 
 X_API Term YAP_NewOpaqueObject(YAP_opaque_tag_t blob_tag, size_t bytes) {
   CELL *pt;
   Term t = Yap_AllocExternalDataInStack((CELL) blob_tag, bytes, &pt);
-    if (t == TermNil)
-        return 0L;
+  if (t == TermNil)
+    return 0L;
+  pt = RepAppl(t);
   blob_tag = pt[1];
   if (blob_tag < USER_BLOB_START ||
       blob_tag >= USER_BLOB_END) {
     Yap_Error(SYSTEM_ERROR_INTERNAL, AbsAppl(pt), "clean opaque: bad blob with tag " UInt_FORMAT ,blob_tag);
     return FALSE;
   }
-  YAP_opaque_tag_t blob_info = blob_tag - USER_BLOB_START;
+  YAP_opaque_tag_t blob_info = blob_tag;
     if (GLOBAL_OpaqueHandlers[blob_info].cut_handler ||
 	GLOBAL_OpaqueHandlers[blob_info].fail_handler ) {
       *HR++ = t;
diff --git a/H/TermExt.h b/H/TermExt.h
index 8fe99d5e6..0f2669596 100755
--- a/H/TermExt.h
+++ b/H/TermExt.h
@@ -95,10 +95,10 @@ typedef enum {
   ARRAY_INT = 0x21,
   ARRAY_FLOAT = 0x22,
   CLAUSE_LIST = 0x40,
-  EXTERNAL_BLOB = 0x100,    /* generic data */
-  GOAL_CUT_POINT = 0x200,
-  USER_BLOB_START = 0x1000, /* user defined blob */
-  USER_BLOB_END = 0x1100    /* end of user defined blob */
+  EXTERNAL_BLOB = 0x0A0,    /* generic data */
+  GOAL_CUT_POINT = 0x0A1,
+  USER_BLOB_START = 0x0100, /* user defined blob */
+  USER_BLOB_END = 0x0200    /* end of user defined blob */
 } big_blob_type;
 
 INLINE_ONLY inline EXTERN blob_type BlobOfFunctor(Functor f);