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-rw-r--r--lib/erl_interface/src/decode/decode_string.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/lib/erl_interface/src/decode/decode_string.c b/lib/erl_interface/src/decode/decode_string.c
new file mode 100644
index 0000000000..bcbdca0438
--- /dev/null
+++ b/lib/erl_interface/src/decode/decode_string.c
@@ -0,0 +1,85 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 1998-2009. All Rights Reserved.
+ *
+ * The contents of this file are subject to the Erlang Public License,
+ * Version 1.1, (the "License"); you may not use this file except in
+ * compliance with the License. You should have received a copy of the
+ * Erlang Public License along with this software. If not, it can be
+ * retrieved online at http://www.erlang.org/.
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * %CopyrightEnd%
+ */
+#include <string.h>
+#include "eidef.h"
+#include "eiext.h"
+#include "putget.h"
+
+/* FIXME fix or document that special requirements on
+ the in data.... */
+
+int ei_decode_string(const char *buf, int *index, char *p)
+{
+ const char *s = buf + *index;
+ const char *s0 = s;
+ int len;
+ int i;
+ int etype;
+
+ switch (get8(s)) {
+ case ERL_STRING_EXT:
+ len = get16be(s);
+
+ if (p) {
+ memmove(p,s,len);
+ p[len] = (char)0;
+ }
+ s += len;
+ break;
+
+ case ERL_LIST_EXT:
+ /* Really long strings are represented as lists of small integers.
+ * We don't know in advance if the whole list is small integers,
+ * but we decode as much as we can, exiting early if we run into a
+ * non-character in the list.
+ */
+ len = get32be(s);
+ if (p) {
+ for (i=0; i<len; i++) {
+ if ((etype = get8(s)) != ERL_SMALL_INTEGER_EXT) {
+ p[i] = (char)0;
+ return -1;
+ }
+ p[i] = get8(s);
+ }
+ p[i] = (char)0;
+ }
+ else {
+ for (i=0; i<len; i++) {
+ if ((etype = get8(s)) != ERL_SMALL_INTEGER_EXT) return -1;
+ s++;
+ }
+ }
+ /* Check NIL tail */
+ if ((etype = get8(s)) != ERL_NIL_EXT) return -1;
+ break;
+
+ case ERL_NIL_EXT:
+ if (p) p[0] = (char)0;
+ break;
+
+ default:
+ return -1;
+ }
+
+
+ *index += s-s0;
+
+ return 0;
+}