auto import from //depot/cupcake/@135843
diff --git a/emulator/qtools/decoder.cpp b/emulator/qtools/decoder.cpp
new file mode 100644
index 0000000..ec53181
--- /dev/null
+++ b/emulator/qtools/decoder.cpp
@@ -0,0 +1,278 @@
+// Copyright 2006 The Android Open Source Project
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include "decoder.h"
+#include "trace_common.h"
+
+// This array provides a fast conversion from the initial byte in
+// a varint-encoded object to the length (in bytes) of that object.
+int prefix_to_len[] = {
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 9, 9, 17, 17
+};
+
+// This array provides a fast conversion from the initial byte in
+// a varint-encoded object to the initial data bits for that object.
+int prefix_to_data[] = {
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+ 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
+ 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
+ 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
+ 112, 113, 114, 115, 116, 117, 118, 119,
+ 120, 121, 122, 123, 124, 125, 126, 127,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 0, 0, 0, 0
+};
+
+signed char prefix_to_signed_data[] = {
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+ 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+ 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
+ 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
+ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
+ 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
+ 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
+ 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
+ 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
+ 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
+ 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
+ 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
+ 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
+ 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff,
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+ 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+ 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
+ 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
+ 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
+ 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff,
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+ 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
+ 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff,
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff,
+ 0x00, 0x01, 0x02, 0x03, 0xfc, 0xfd, 0xfe, 0xff,
+ 0x00, 0x01, 0xfe, 0xff, 0x00, 0xff, 0x00, 0xff,
+};
+
+Decoder::Decoder()
+{
+ filename_ = NULL;
+ fstream_ = NULL;
+ next_ = NULL;
+ end_ = NULL;
+}
+
+Decoder::~Decoder()
+{
+ Close();
+ delete[] filename_;
+}
+
+void Decoder::Close()
+{
+ if (fstream_) {
+ fclose(fstream_);
+ fstream_ = NULL;
+ }
+}
+
+void Decoder::Open(char *filename)
+{
+ if (filename_ != NULL) {
+ delete[] filename_;
+ }
+ filename_ = new char[strlen(filename) + 1];
+ strcpy(filename_, filename);
+ fstream_ = fopen(filename_, "r");
+ if (fstream_ == NULL) {
+ perror(filename_);
+ exit(1);
+ }
+
+ int rval = fread(buf_, 1, kBufSize, fstream_);
+ if (rval != kBufSize) {
+ if (ferror(fstream_)) {
+ perror(filename_);
+ exit(1);
+ }
+ if (!feof(fstream_)) {
+ fprintf(stderr, "Unexpected short fread() before eof\n");
+ exit(1);
+ }
+ }
+ next_ = buf_;
+ end_ = buf_ + rval;
+}
+
+void Decoder::FillBuffer()
+{
+ assert(next_ <= end_);
+
+ if (end_ - next_ < kDecodingSpace && end_ == &buf_[kBufSize]) {
+ // Copy the unused bytes left at the end to the beginning of the
+ // buffer.
+ int len = end_ - next_;
+ if (len > 0)
+ memcpy(buf_, next_, len);
+
+ // Read enough bytes to fill up the buffer, if possible.
+ int nbytes = kBufSize - len;
+ int rval = fread(buf_ + len, 1, nbytes, fstream_);
+ if (rval < nbytes) {
+ if (ferror(fstream_)) {
+ perror(filename_);
+ exit(1);
+ }
+ if (!feof(fstream_)) {
+ fprintf(stderr, "Unexpected short fread() before eof\n");
+ exit(1);
+ }
+ }
+ end_ = &buf_[len + rval];
+ next_ = buf_;
+ }
+}
+
+void Decoder::Read(char *dest, int len)
+{
+ while (len > 0) {
+ int nbytes = end_ - next_;
+ if (nbytes == 0) {
+ FillBuffer();
+ nbytes = end_ - next_;
+ if (nbytes == 0)
+ break;
+ }
+ if (nbytes > len)
+ nbytes = len;
+ memcpy(dest, next_, nbytes);
+ dest += nbytes;
+ len -= nbytes;
+ next_ += nbytes;
+ }
+}
+
+// Decode a varint-encoded object starting at the current position in
+// the array "buf_" and return the decoded value as a 64-bit integer.
+// A varint-encoded object has an initial prefix that specifies how many
+// data bits follow. If the first bit is zero, for example, then there
+// are 7 data bits that follow. The table below shows the prefix values
+// and corresponding data bits.
+//
+// Prefix Bytes Data bits
+// 0 1 7
+// 10 2 14
+// 110 3 21
+// 1110 4 28
+// 11110 5 35
+// 111110 6 42
+// 11111100 9 64
+// 11111101 reserved
+// 11111110 reserved
+// 11111111 reserved
+int64_t Decoder::Decode(bool is_signed)
+{
+ int64_t val64;
+
+ if (end_ - next_ < kDecodingSpace)
+ FillBuffer();
+
+#if BYTE_ORDER == BIG_ENDIAN
+ uint8_t byte0 = *next_;
+
+ // Get the number of bytes to decode based on the first byte.
+ int len = prefix_to_len[byte0];
+
+ if (next_ + len > end_) {
+ fprintf(stderr, "%s: decoding past end of file.\n", filename_);
+ exit(1);
+ }
+
+ // Get the first data byte.
+ if (is_signed)
+ val64 = prefix_to_signed_data[byte0];
+ else
+ val64 = prefix_to_data[byte0];
+
+ next_ += 1;
+ for (int ii = 1; ii < len; ++ii) {
+ val64 = (val64 << 8) | *next_++;
+ }
+#else
+ // If we are on a little-endian machine, then use large, unaligned loads.
+ uint64_t data = *(reinterpret_cast<uint64_t*>(next_));
+ uint8_t byte0 = data;
+ data = bswap64(data);
+
+ // Get the number of bytes to decode based on the first byte.
+ int len = prefix_to_len[byte0];
+
+ if (next_ + len > end_) {
+ fprintf(stderr, "%s: decoding past end of file.\n", filename_);
+ exit(1);
+ }
+
+ // Get the first data byte.
+ if (is_signed)
+ val64 = prefix_to_signed_data[byte0];
+ else
+ val64 = prefix_to_data[byte0];
+
+ switch (len) {
+ case 1:
+ break;
+ case 2:
+ val64 = (val64 << 8) | ((data >> 48) & 0xffull);
+ break;
+ case 3:
+ val64 = (val64 << 16) | ((data >> 40) & 0xffffull);
+ break;
+ case 4:
+ val64 = (val64 << 24) | ((data >> 32) & 0xffffffull);
+ break;
+ case 5:
+ val64 = (val64 << 32) | ((data >> 24) & 0xffffffffull);
+ break;
+ case 6:
+ val64 = (val64 << 40) | ((data >> 16) & 0xffffffffffull);
+ break;
+ case 9:
+ data = *(reinterpret_cast<uint64_t*>(&next_[1]));
+ val64 = bswap64(data);
+ break;
+ }
+ next_ += len;
+#endif
+ return val64;
+}