1 #include <cstring>
2
3 #include "Common/Log.h"
4 #include "Common/Data/Format/RIFF.h"
5
flipID(uint32_t id)6 inline uint32_t flipID(uint32_t id) {
7 return ((id >> 24) & 0xFF) | ((id >> 8) & 0xFF00) | ((id << 8) & 0xFF0000) | ((id << 24) & 0xFF000000);
8 }
9
RIFFReader(const uint8_t * data,int dataSize)10 RIFFReader::RIFFReader(const uint8_t *data, int dataSize) {
11 data_ = new uint8_t[dataSize];
12 memcpy(data_, data, dataSize);
13 depth_ = 0;
14 pos_ = 0;
15 eof_ = dataSize;
16 fileSize_ = dataSize;
17 }
18
~RIFFReader()19 RIFFReader::~RIFFReader() {
20 delete[] data_;
21 }
22
ReadInt()23 int RIFFReader::ReadInt() {
24 if (data_ && pos_ < eof_ - 3) {
25 pos_ += 4;
26 return *(int *)(data_ + pos_ - 4);
27 }
28 return 0;
29 }
30
Descend(uint32_t intoId)31 bool RIFFReader::Descend(uint32_t intoId) {
32 if (depth_ > 30)
33 return false;
34
35 intoId = flipID(intoId);
36 bool found = false;
37
38 // save information to restore after the next Ascend
39 stack[depth_].parentStartLocation = pos_;
40 stack[depth_].parentEOF = eof_;
41
42 // let's search through children..
43 while (pos_ < eof_) {
44 int id = ReadInt();
45 int length = ReadInt();
46 int startLocation = pos_;
47
48 if (pos_ + length > fileSize_) {
49 ERROR_LOG(IO, "Block extends outside of RIFF file - failing descend");
50 pos_ = stack[depth_].parentStartLocation;
51 return false;
52 }
53
54 if (id == intoId) {
55 stack[depth_].ID = intoId;
56 stack[depth_].length = length;
57 stack[depth_].startLocation = startLocation;
58 found = true;
59 break;
60 } else {
61 if (length > 0) {
62 pos_ += length; // try next block
63 } else {
64 ERROR_LOG(IO, "Bad data in RIFF file : block length %d. Not descending.", length);
65 pos_ = stack[depth_].parentStartLocation;
66 return false;
67 }
68 }
69 }
70
71 // if we found nothing, return false so the caller can skip this
72 if (!found) {
73 pos_ = stack[depth_].parentStartLocation;
74 return false;
75 }
76
77 // descend into it
78 // pos was set inside the loop above
79 eof_ = stack[depth_].startLocation + stack[depth_].length;
80 depth_++;
81 return true;
82 }
83
Ascend()84 void RIFFReader::Ascend() {
85 // ascend, and restore information
86 depth_--;
87 pos_ = stack[depth_].parentStartLocation;
88 eof_ = stack[depth_].parentEOF;
89 }
90
ReadData(void * what,int count)91 void RIFFReader::ReadData(void *what, int count) {
92 memcpy(what, data_ + pos_, count);
93 pos_ += count;
94 count &= 3;
95 if (count) {
96 count = 4 - count;
97 pos_ += count;
98 }
99 }
100
GetCurrentChunkSize()101 int RIFFReader::GetCurrentChunkSize() {
102 if (depth_)
103 return stack[depth_ - 1].length;
104 else
105 return 0;
106 }
107
108