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-rw-r--r--tensorflow/core/lib/core/coding.cc164
1 files changed, 164 insertions, 0 deletions
diff --git a/tensorflow/core/lib/core/coding.cc b/tensorflow/core/lib/core/coding.cc
new file mode 100644
index 0000000000..efff554742
--- /dev/null
+++ b/tensorflow/core/lib/core/coding.cc
@@ -0,0 +1,164 @@
+#include "tensorflow/core/lib/core/coding.h"
+
+namespace tensorflow {
+namespace core {
+
+void EncodeFixed32(char* buf, uint32 value) {
+ if (port::kLittleEndian) {
+ memcpy(buf, &value, sizeof(value));
+ } else {
+ buf[0] = value & 0xff;
+ buf[1] = (value >> 8) & 0xff;
+ buf[2] = (value >> 16) & 0xff;
+ buf[3] = (value >> 24) & 0xff;
+ }
+}
+
+void EncodeFixed64(char* buf, uint64 value) {
+ if (port::kLittleEndian) {
+ memcpy(buf, &value, sizeof(value));
+ } else {
+ buf[0] = value & 0xff;
+ buf[1] = (value >> 8) & 0xff;
+ buf[2] = (value >> 16) & 0xff;
+ buf[3] = (value >> 24) & 0xff;
+ buf[4] = (value >> 32) & 0xff;
+ buf[5] = (value >> 40) & 0xff;
+ buf[6] = (value >> 48) & 0xff;
+ buf[7] = (value >> 56) & 0xff;
+ }
+}
+
+void PutFixed32(string* dst, uint32 value) {
+ char buf[sizeof(value)];
+ EncodeFixed32(buf, value);
+ dst->append(buf, sizeof(buf));
+}
+
+void PutFixed64(string* dst, uint64 value) {
+ char buf[sizeof(value)];
+ EncodeFixed64(buf, value);
+ dst->append(buf, sizeof(buf));
+}
+
+char* EncodeVarint32(char* dst, uint32 v) {
+ // Operate on characters as unsigneds
+ unsigned char* ptr = reinterpret_cast<unsigned char*>(dst);
+ static const int B = 128;
+ if (v < (1 << 7)) {
+ *(ptr++) = v;
+ } else if (v < (1 << 14)) {
+ *(ptr++) = v | B;
+ *(ptr++) = v >> 7;
+ } else if (v < (1 << 21)) {
+ *(ptr++) = v | B;
+ *(ptr++) = (v >> 7) | B;
+ *(ptr++) = v >> 14;
+ } else if (v < (1 << 28)) {
+ *(ptr++) = v | B;
+ *(ptr++) = (v >> 7) | B;
+ *(ptr++) = (v >> 14) | B;
+ *(ptr++) = v >> 21;
+ } else {
+ *(ptr++) = v | B;
+ *(ptr++) = (v >> 7) | B;
+ *(ptr++) = (v >> 14) | B;
+ *(ptr++) = (v >> 21) | B;
+ *(ptr++) = v >> 28;
+ }
+ return reinterpret_cast<char*>(ptr);
+}
+
+void PutVarint32(string* dst, uint32 v) {
+ char buf[5];
+ char* ptr = EncodeVarint32(buf, v);
+ dst->append(buf, ptr - buf);
+}
+
+char* EncodeVarint64(char* dst, uint64 v) {
+ static const int B = 128;
+ unsigned char* ptr = reinterpret_cast<unsigned char*>(dst);
+ while (v >= B) {
+ *(ptr++) = (v & (B - 1)) | B;
+ v >>= 7;
+ }
+ *(ptr++) = static_cast<unsigned char>(v);
+ return reinterpret_cast<char*>(ptr);
+}
+
+void PutVarint64(string* dst, uint64 v) {
+ char buf[10];
+ char* ptr = EncodeVarint64(buf, v);
+ dst->append(buf, ptr - buf);
+}
+
+int VarintLength(uint64_t v) {
+ int len = 1;
+ while (v >= 128) {
+ v >>= 7;
+ len++;
+ }
+ return len;
+}
+
+const char* GetVarint32PtrFallback(const char* p, const char* limit,
+ uint32* value) {
+ uint32 result = 0;
+ for (uint32 shift = 0; shift <= 28 && p < limit; shift += 7) {
+ uint32 byte = *(reinterpret_cast<const unsigned char*>(p));
+ p++;
+ if (byte & 128) {
+ // More bytes are present
+ result |= ((byte & 127) << shift);
+ } else {
+ result |= (byte << shift);
+ *value = result;
+ return reinterpret_cast<const char*>(p);
+ }
+ }
+ return NULL;
+}
+
+bool GetVarint32(StringPiece* input, uint32* value) {
+ const char* p = input->data();
+ const char* limit = p + input->size();
+ const char* q = GetVarint32Ptr(p, limit, value);
+ if (q == NULL) {
+ return false;
+ } else {
+ *input = StringPiece(q, limit - q);
+ return true;
+ }
+}
+
+const char* GetVarint64Ptr(const char* p, const char* limit, uint64* value) {
+ uint64 result = 0;
+ for (uint32 shift = 0; shift <= 63 && p < limit; shift += 7) {
+ uint64 byte = *(reinterpret_cast<const unsigned char*>(p));
+ p++;
+ if (byte & 128) {
+ // More bytes are present
+ result |= ((byte & 127) << shift);
+ } else {
+ result |= (byte << shift);
+ *value = result;
+ return reinterpret_cast<const char*>(p);
+ }
+ }
+ return NULL;
+}
+
+bool GetVarint64(StringPiece* input, uint64* value) {
+ const char* p = input->data();
+ const char* limit = p + input->size();
+ const char* q = GetVarint64Ptr(p, limit, value);
+ if (q == NULL) {
+ return false;
+ } else {
+ *input = StringPiece(q, limit - q);
+ return true;
+ }
+}
+
+} // namespace core
+} // namespace tensorflow