From dce63c8bfc0eb0d389aa3a7836ac03df9438a527 Mon Sep 17 00:00:00 2001
From: vtarasov <vtarasov@c6295689-39f2-0310-b995-f0e70906c6a9>
Date: Sun, 29 May 2011 17:47:54 +0000
Subject: [PATCH] libopensc: new exported function to reverse memory buffer

git-svn-id: https://www.opensc-project.org/svnp/opensc/trunk@5516 c6295689-39f2-0310-b995-f0e70906c6a9
---
 src/libopensc/libopensc.exports |  1 +
 src/libopensc/opensc.h          |  1 +
 src/libopensc/sc.c              | 17 +++++++++++++++++
 3 files changed, 19 insertions(+)

diff --git a/src/libopensc/libopensc.exports b/src/libopensc/libopensc.exports
index 8449c67f..28143df9 100644
--- a/src/libopensc/libopensc.exports
+++ b/src/libopensc/libopensc.exports
@@ -117,6 +117,7 @@ sc_lock
 sc_logout
 sc_make_cache_dir
 sc_mem_clear
+sc_mem_reverse
 sc_path_print
 sc_path_set
 sc_pin_cmd
diff --git a/src/libopensc/opensc.h b/src/libopensc/opensc.h
index f208c06d..7a81b756 100644
--- a/src/libopensc/opensc.h
+++ b/src/libopensc/opensc.h
@@ -1149,6 +1149,7 @@ int sc_base64_decode(const char *in, u8 *out, size_t outlen);
  */
 void sc_mem_clear(void *ptr, size_t len);
 void *sc_mem_alloc_secure(size_t len);
+int sc_mem_reverse(unsigned char *buf, size_t len);
 
 int sc_get_cache_dir(sc_context_t *ctx, char *buf, size_t bufsize);
 int sc_make_cache_dir(sc_context_t *ctx);
diff --git a/src/libopensc/sc.c b/src/libopensc/sc.c
index bd10007f..12565339 100644
--- a/src/libopensc/sc.c
+++ b/src/libopensc/sc.c
@@ -727,6 +727,23 @@ void sc_mem_clear(void *ptr, size_t len)
 #endif
 }
 
+int sc_mem_reverse(unsigned char *buf, size_t len)
+{
+	unsigned char ch;
+	size_t ii;
+
+	if (!buf || !len)
+		return SC_ERROR_INVALID_ARGUMENTS;
+
+	for (ii = 0; ii < len / 2; ii++)   {
+		ch = *(buf + ii);
+		*(buf + ii) = *(buf + len - 1 - ii);
+		*(buf + len - 1 - ii) = ch;
+	}
+
+	return 0;
+}
+
 static int 
 sc_remote_apdu_allocate(struct sc_remote_data *rdata, 
 		struct sc_remote_apdu **new_rapdu)