X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/1d9ac42faa4a9e1ffd0cd0a8124600acb3696209..e7dc130f304bb10854e4b38488fabd258c99dcab:/crc32.c?ds=sidebyside

diff --git a/crc32.c b/crc32.c
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+/* -*-c-*-
+ *
+ * $Id: crc32.c,v 1.1 2001/04/19 18:26:32 mdw Exp $
+ *
+ * Generic hash wrapper for CRC32
+ *
+ * (c) 2001 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------* 
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ * 
+ * Catacomb is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Library General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Revision history --------------------------------------------------* 
+ *
+ * $Log: crc32.c,v $
+ * Revision 1.1  2001/04/19 18:26:32  mdw
+ * Add CRC as another hash function.
+ *
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <mLib/crc32.h>
+#include <mLib/sub.h>
+
+#include "arena.h"
+#include "crc32.h"
+#include "ghash.h"
+#include "paranoia.h"
+
+/*----- Main code ---------------------------------------------------------*/
+
+typedef struct gctx {
+  ghash h;
+  uint32 c;
+  octet buf[4];
+} gctx;
+
+static const ghash_ops gops;
+
+static ghash *ghinit(void)
+{
+  gctx *g = S_CREATE(gctx);
+  g->h.ops = &gops;
+  g->c = 0;
+  return (&g->h);
+}
+
+static void ghhash(ghash *h, const void *p, size_t sz)
+{
+  gctx *g = (gctx *)h;
+  CRC32(g->c, g->c, p, sz);
+}
+
+static octet *ghdone(ghash *h, void *buf)
+{
+  gctx *g = (gctx *)h;
+  if (!buf)
+    buf = g->buf;
+  STORE32(buf, g->c);
+  return (buf);
+}
+
+static void ghdestroy(ghash *h)
+{
+  gctx *g = (gctx *)h;
+  BURN(*g);
+  S_DESTROY(g);
+}
+
+static void 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 = { &gcrc32, ghhash, ghdone, ghdestroy, ghcopy };
+const gchash gcrc32 = { "crc32", 4, ghinit };
+
+/*----- That's all, folks -------------------------------------------------*/