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-rw-r--r--app/nginx/src/core/ngx_crc.h39
1 files changed, 39 insertions, 0 deletions
diff --git a/app/nginx/src/core/ngx_crc.h b/app/nginx/src/core/ngx_crc.h
new file mode 100644
index 0000000..35981bc
--- /dev/null
+++ b/app/nginx/src/core/ngx_crc.h
@@ -0,0 +1,39 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ * Copyright (C) Nginx, Inc.
+ */
+
+
+#ifndef _NGX_CRC_H_INCLUDED_
+#define _NGX_CRC_H_INCLUDED_
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+
+
+/* 32-bit crc16 */
+
+static ngx_inline uint32_t
+ngx_crc(u_char *data, size_t len)
+{
+ uint32_t sum;
+
+ for (sum = 0; len; len--) {
+
+ /*
+ * gcc 2.95.2 x86 and icc 7.1.006 compile
+ * that operator into the single "rol" opcode,
+ * msvc 6.0sp2 compiles it into four opcodes.
+ */
+ sum = sum >> 1 | sum << 31;
+
+ sum += *data++;
+ }
+
+ return sum;
+}
+
+
+#endif /* _NGX_CRC_H_INCLUDED_ */