intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 79 insertions, 0 deletions

diff --git a/library/cpp/digest/md5/md5.h b/library/cpp/digest/md5/md5.h
new file mode 100644
index 0000000000..1568567e3c
--- /dev/null
+++ b/library/cpp/digest/md5/md5.h
@@ -0,0 +1,79 @@
+#pragma once
+
+#include <util/system/defaults.h>
+#include <util/generic/string.h>
+#include <util/generic/array_ref.h>
+#include <util/generic/strbuf.h>
+
+class IInputStream;
+
+class MD5 {
+public:
+    MD5() {
+        Init();
+    }
+
+    void Init();
+
+    inline MD5& Update(const void* data, size_t len) {
+        const char* buf = (const char*)data;
+
+        while (len) {
+            // NOTE: we don't want buffSz to be near Max<unsigned int>()
+            // because otherwise integer overflow might happen in UpdatePart
+            const unsigned int buffSz = Min(size_t(Max<unsigned int>() / 2), len);
+
+            UpdatePart(buf, buffSz);
+            buf += buffSz;
+            len -= buffSz;
+        }
+        return *this;
+    }
+
+    inline MD5& Update(const TStringBuf& data) {
+        return Update(data.data(), data.size());
+    }
+
+    void Pad();
+    unsigned char* Final(unsigned char[16]);
+
+    // buf must be char[33];
+    char* End(char* buf);
+
+    // buf must be char[25];
+    char* End_b64(char* buf);
+
+    // 8-byte xor-based mix
+    ui64 EndHalfMix();
+
+    MD5& Update(IInputStream* in);
+
+    /*
+     * Return hex-encoded md5 checksum for given file.
+     *
+     * Return nullptr / empty string if the file does not exist.
+     */
+    static char* File(const char* filename, char* buf);
+    static TString File(const TString& filename);
+
+    static char* Data(const void* data, size_t len, char* buf);
+    static TString Data(TArrayRef<ui8> data);
+    static TString Data(TStringBuf data);
+    static char* Stream(IInputStream* in, char* buf);
+
+    static TString Calc(const TStringBuf& data);    // 32-byte hex-encoded
+    static TString CalcRaw(const TStringBuf& data); // 16-byte raw
+
+    static ui64 CalcHalfMix(const TStringBuf& data);
+    static ui64 CalcHalfMix(const char* data, size_t len);
+
+    static bool IsMD5(const TStringBuf& data);
+
+private:
+    void UpdatePart(const void* data, unsigned int len);
+
+private:
+    ui32 State[4];            /* state (ABCD) */
+    ui32 Count[2];            /* number of bits, modulo 2^64 (lsb first) */
+    unsigned char Buffer[64]; /* input buffer */
+};