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28 
29 #ifndef UTIL_DEBUGINFO_BYTEREADER_INL_H__
30 #define UTIL_DEBUGINFO_BYTEREADER_INL_H__
31 
32 #include "common/dwarf/bytereader.h"
33 
34 #include <assert.h>
35 
36 namespace dwarf2reader {
37 
ReadOneByte(const char * buffer)38 inline uint8 ByteReader::ReadOneByte(const char* buffer) const {
39   return buffer[0];
40 }
41 
ReadTwoBytes(const char * signed_buffer)42 inline uint16 ByteReader::ReadTwoBytes(const char* signed_buffer) const {
43   const unsigned char *buffer
44     = reinterpret_cast<const unsigned char *>(signed_buffer);
45   const uint16 buffer0 = buffer[0];
46   const uint16 buffer1 = buffer[1];
47   if (endian_ == ENDIANNESS_LITTLE) {
48     return buffer0 | buffer1 << 8;
49   } else {
50     return buffer1 | buffer0 << 8;
51   }
52 }
53 
ReadFourBytes(const char * signed_buffer)54 inline uint64 ByteReader::ReadFourBytes(const char* signed_buffer) const {
55   const unsigned char *buffer
56     = reinterpret_cast<const unsigned char *>(signed_buffer);
57   const uint32 buffer0 = buffer[0];
58   const uint32 buffer1 = buffer[1];
59   const uint32 buffer2 = buffer[2];
60   const uint32 buffer3 = buffer[3];
61   if (endian_ == ENDIANNESS_LITTLE) {
62     return buffer0 | buffer1 << 8 | buffer2 << 16 | buffer3 << 24;
63   } else {
64     return buffer3 | buffer2 << 8 | buffer1 << 16 | buffer0 << 24;
65   }
66 }
67 
ReadEightBytes(const char * signed_buffer)68 inline uint64 ByteReader::ReadEightBytes(const char* signed_buffer) const {
69   const unsigned char *buffer
70     = reinterpret_cast<const unsigned char *>(signed_buffer);
71   const uint64 buffer0 = buffer[0];
72   const uint64 buffer1 = buffer[1];
73   const uint64 buffer2 = buffer[2];
74   const uint64 buffer3 = buffer[3];
75   const uint64 buffer4 = buffer[4];
76   const uint64 buffer5 = buffer[5];
77   const uint64 buffer6 = buffer[6];
78   const uint64 buffer7 = buffer[7];
79   if (endian_ == ENDIANNESS_LITTLE) {
80     return buffer0 | buffer1 << 8 | buffer2 << 16 | buffer3 << 24 |
81       buffer4 << 32 | buffer5 << 40 | buffer6 << 48 | buffer7 << 56;
82   } else {
83     return buffer7 | buffer6 << 8 | buffer5 << 16 | buffer4 << 24 |
84       buffer3 << 32 | buffer2 << 40 | buffer1 << 48 | buffer0 << 56;
85   }
86 }
87 
88 // Read an unsigned LEB128 number.  Each byte contains 7 bits of
89 // information, plus one bit saying whether the number continues or
90 // not.
91 
ReadUnsignedLEB128(const char * buffer,size_t * len)92 inline uint64 ByteReader::ReadUnsignedLEB128(const char* buffer,
93                                              size_t* len) const {
94   uint64 result = 0;
95   size_t num_read = 0;
96   unsigned int shift = 0;
97   unsigned char byte;
98 
99   do {
100     byte = *buffer++;
101     num_read++;
102 
103     result |= (static_cast<uint64>(byte & 0x7f)) << shift;
104 
105     shift += 7;
106 
107   } while (byte & 0x80);
108 
109   *len = num_read;
110 
111   return result;
112 }
113 
114 // Read a signed LEB128 number.  These are like regular LEB128
115 // numbers, except the last byte may have a sign bit set.
116 
ReadSignedLEB128(const char * buffer,size_t * len)117 inline int64 ByteReader::ReadSignedLEB128(const char* buffer,
118                                           size_t* len) const {
119   int64 result = 0;
120   unsigned int shift = 0;
121   size_t num_read = 0;
122   unsigned char byte;
123 
124   do {
125       byte = *buffer++;
126       num_read++;
127       result |= (static_cast<uint64>(byte & 0x7f) << shift);
128       shift += 7;
129   } while (byte & 0x80);
130 
131   if ((shift < 8 * sizeof (result)) && (byte & 0x40))
132     result |= -((static_cast<int64>(1)) << shift);
133   *len = num_read;
134   return result;
135 }
136 
ReadOffset(const char * buffer)137 inline uint64 ByteReader::ReadOffset(const char* buffer) const {
138   assert(this->offset_reader_);
139   return (this->*offset_reader_)(buffer);
140 }
141 
ReadAddress(const char * buffer)142 inline uint64 ByteReader::ReadAddress(const char* buffer) const {
143   assert(this->address_reader_);
144   return (this->*address_reader_)(buffer);
145 }
146 
SetCFIDataBase(uint64 section_base,const char * buffer_base)147 inline void ByteReader::SetCFIDataBase(uint64 section_base,
148                                        const char *buffer_base) {
149   section_base_ = section_base;
150   buffer_base_ = buffer_base;
151   have_section_base_ = true;
152 }
153 
SetTextBase(uint64 text_base)154 inline void ByteReader::SetTextBase(uint64 text_base) {
155   text_base_ = text_base;
156   have_text_base_ = true;
157 }
158 
SetDataBase(uint64 data_base)159 inline void ByteReader::SetDataBase(uint64 data_base) {
160   data_base_ = data_base;
161   have_data_base_ = true;
162 }
163 
SetFunctionBase(uint64 function_base)164 inline void ByteReader::SetFunctionBase(uint64 function_base) {
165   function_base_ = function_base;
166   have_function_base_ = true;
167 }
168 
ClearFunctionBase()169 inline void ByteReader::ClearFunctionBase() {
170   have_function_base_ = false;
171 }
172 
173 }  // namespace dwarf2reader
174 
175 #endif  // UTIL_DEBUGINFO_BYTEREADER_INL_H__
176