Add an internal-representation no-op function.

[u/mdw/catacomb] / ghash-def.h

diff --git a/ghash-def.h b/ghash-def.h
index db87d1f..9065f5b 100644 (file)
--- a/ghash-def.h
+++ b/ghash-def.h
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: ghash-def.h,v 1.2 2000/06/17 11:22:03 mdw Exp $
+ * $Id: ghash-def.h,v 1.5 2001/01/25 21:39:58 mdw Exp $
  *
  * Definitions for generic hash interface
  *
@@ -30,6 +30,18 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: ghash-def.h,v $
+ * Revision 1.5  2001/01/25 21:39:58  mdw
+ * Burn the hash context when it's done with, for paranoia's sake.
+ *
+ * Revision 1.4  2000/07/15 10:00:58  mdw
+ * New generic hash operation for copying hash contexts.
+ *
+ * Revision 1.3  2000/07/02 18:27:42  mdw
+ * (ghash->ops->done): Interface change.  Passing in a null buffer pointer
+ * uses a buffer internal to the ghash object.  The operation returns the
+ * address of the buffer it used.  Clients of generic hashes no longer need
+ * to use dynamically allocated memory for hash results.
+ *
  * Revision 1.2  2000/06/17 11:22:03  mdw
  * Use secure arena for memory allocation.  Minor changes in the generic
  * hash interface.
@@ -59,6 +71,10 @@
 #  include "ghash.h"
 #endif
 
+#ifndef CATACOMB_PARANOIA_H
+#  include "paranoia.h"
+#endif
+
 /*----- Generic hash function interface -----------------------------------*/
 
 /* --- @GHASH_DEF@ --- *
@@ -75,6 +91,7 @@ static const ghash_ops gops;                                          \
 typedef struct gctx {                                                  \
   ghash h;                                                             \
   pre##_ctx c;                                                         \
+  octet buf[PRE##_HASHSZ];                                             \
 } gctx;                                                                        \
                                                                        \
 static ghash *ghinit(void)                                             \
@@ -91,19 +108,32 @@ static void ghhash(ghash *h, const void *p, size_t sz)                     \
   pre##_hash(&g->c, p, sz);                                            \
 }                                                                      \
                                                                        \
-static void ghdone(ghash *h, void *buf)                                        \
+static octet *ghdone(ghash *h, void *buf)                              \
 {                                                                      \
   gctx *g = (gctx *)h;                                                 \
+  if (!buf)                                                            \
+    buf = g->buf;                                                      \
   pre##_done(&g->c, buf);                                              \
+  return (buf);                                                                \
 }                                                                      \
                                                                        \
 static void ghdestroy(ghash *h)                                                \
 {                                                                      \
   gctx *g = (gctx *)h;                                                 \
+  BURN(*g);                                                            \
   S_DESTROY(g);                                                                \
 }                                                                      \
                                                                        \
-static const ghash_ops gops = { &pre, ghhash, ghdone, ghdestroy };     \
+static ghash *ghcopy(ghash *h)                                         \
+{                                                                      \
+  gctx *g = (gctx *)h;                                                 \
+  gctx *gg = S_CREATE(gctx);                                           \
+  memcpy(gg, g, sizeof(gctx));                                         \
+  return (&gg->h);                                                     \
+}                                                                      \
+                                                                       \
+static const ghash_ops gops =                                          \
+  { &pre, ghhash, ghdone, ghdestroy, ghcopy };                         \
 const gchash pre = { #pre, PRE##_HASHSZ, ghinit };
 
 /*----- That's all, folks -------------------------------------------------*/