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Diffstat (limited to 'contrib/bearssl/src/int/i32_decode.c')
-rw-r--r--contrib/bearssl/src/int/i32_decode.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/contrib/bearssl/src/int/i32_decode.c b/contrib/bearssl/src/int/i32_decode.c
new file mode 100644
index 000000000000..f28903846656
--- /dev/null
+++ b/contrib/bearssl/src/int/i32_decode.c
@@ -0,0 +1,63 @@
+/*
+ * 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_i32_decode(uint32_t *x, const void *src, size_t len)
+{
+ const unsigned char *buf;
+ size_t u, v;
+
+ buf = src;
+ u = len;
+ v = 1;
+ for (;;) {
+ if (u < 4) {
+ uint32_t w;
+
+ if (u < 2) {
+ if (u == 0) {
+ break;
+ } else {
+ w = buf[0];
+ }
+ } else {
+ if (u == 2) {
+ w = br_dec16be(buf);
+ } else {
+ w = ((uint32_t)buf[0] << 16)
+ | br_dec16be(buf + 1);
+ }
+ }
+ x[v ++] = w;
+ break;
+ } else {
+ u -= 4;
+ x[v ++] = br_dec32be(buf + u);
+ }
+ }
+ x[0] = br_i32_bit_length(x + 1, v - 1);
+}