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-rw-r--r--test/monniaux/BearSSL/src/int/i31_encode.c79
1 files changed, 79 insertions, 0 deletions
diff --git a/test/monniaux/BearSSL/src/int/i31_encode.c b/test/monniaux/BearSSL/src/int/i31_encode.c
new file mode 100644
index 00000000..b6b40c45
--- /dev/null
+++ b/test/monniaux/BearSSL/src/int/i31_encode.c
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "inner.h"
+
+/* see inner.h */
+void
+br_i31_encode(void *dst, size_t len, const uint32_t *x)
+{
+ unsigned char *buf;
+ size_t k, xlen;
+ uint32_t acc;
+ int acc_len;
+
+ xlen = (x[0] + 31) >> 5;
+ if (xlen == 0) {
+ memset(dst, 0, len);
+ return;
+ }
+ buf = (unsigned char *)dst + len;
+ k = 1;
+ acc = 0;
+ acc_len = 0;
+ while (len != 0) {
+ uint32_t w;
+
+ w = (k <= xlen) ? x[k] : 0;
+ k ++;
+ if (acc_len == 0) {
+ acc = w;
+ acc_len = 31;
+ } else {
+ uint32_t z;
+
+ z = acc | (w << acc_len);
+ acc_len --;
+ acc = w >> (31 - acc_len);
+ if (len >= 4) {
+ buf -= 4;
+ len -= 4;
+ br_enc32be(buf, z);
+ } else {
+ switch (len) {
+ case 3:
+ buf[-3] = (unsigned char)(z >> 16);
+ /* fall through */
+ case 2:
+ buf[-2] = (unsigned char)(z >> 8);
+ /* fall through */
+ case 1:
+ buf[-1] = (unsigned char)z;
+ break;
+ }
+ return;
+ }
+ }
+ }
+}