1 files changed, 84 insertions, 0 deletions
diff --git a/util/membuf.c b/util/membuf.c
new file mode 100644
index 0000000..44347fa
--- /dev/null
+++ b/util/membuf.c
@@ -0,0 +1,84 @@
+/* membuf.c - A simple implementation of a dynamic buffer
+ *	Copyright (C) 2001, 2003 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+ * USA.
+ */
+
+#include <config.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+
+#include "util.h"
+
+
+/* A simple implementation of a dynamic buffer.  Use init_membuf() to
+   create a buffer, put_membuf to append bytes and get_membuf to
+   release and return the buffer.  Allocation errors are detected but
+   only returned at the final get_membuf(), this helps not to clutter
+   the code with out of core checks.  */
+
+void
+init_membuf (membuf_t *mb, int initiallen)
+{
+  mb->len = 0;
+  mb->size = initiallen;
+  mb->out_of_core = 0;
+  mb->buf = xmalloc (initiallen);
+  if (!mb->buf)
+      mb->out_of_core = errno;
+}
+
+
+void
+put_membuf (membuf_t *mb, const void *buf, size_t len)
+{
+  if (mb->out_of_core)
+    return;
+
+  if (mb->len + len >= mb->size)
+    {
+      char *p;
+      
+      mb->size += len + 1024;
+      p = xrealloc (mb->buf, mb->size);
+      mb->buf = p;
+    }
+  memcpy (mb->buf + mb->len, buf, len);
+  mb->len += len;
+}
+
+
+void *
+get_membuf (membuf_t *mb, size_t *len)
+{
+  char *p;
+
+  if (mb->out_of_core)
+    {
+      xfree (mb->buf);
+      mb->buf = NULL;
+      return NULL;
+    }
+
+  p = mb->buf;
+  *len = mb->len;
+  mb->buf = NULL;
+  mb->out_of_core = ENOMEM; /* hack to make sure it won't get reused. */
+  return p;
+}