summaryrefslogtreecommitdiff
path: root/xdelta3/testing/file.h
blob: a204d74c3e8b634643f31e832bfdf844b65db767 (plain)
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
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
/* -*- Mode: C++ -*-  */
class Block;
class BlockIterator;
class TmpFile;

class Block {
public:
  Block()
    : data_(NULL),
      data_size_(0),
      size_(0) { }

  ~Block() {
    if (data_) {
      delete [] data_;
    }
  }

  size_t Size() const {
    return size_;
  }

  uint8_t operator[](size_t i) const {
    CHECK_LT(i, size_);
    return data_[i];
  }

  uint8_t* Data() const {
    if (data_ == NULL) {
      CHECK_EQ(0, size_);
      data_size_ = 1;
      data_ = new uint8_t[1];
    }
    return data_;
  }

  // For writing to blocks
  void Append(const uint8_t *data, size_t size) {
    if (data_ == NULL) {
      CHECK_EQ(0, size_);
      CHECK_EQ(0, data_size_);
      data_ = new uint8_t[Constants::BLOCK_SIZE];
      data_size_ = Constants::BLOCK_SIZE;
    }

    if (size_ + size > data_size_) {
      uint8_t *tmp = data_;
      while (size_ + size > data_size_) {
	data_size_ *= 2;
      }
      data_ = new uint8_t[data_size_];
      memcpy(data_, tmp, size_);
      delete tmp;
    }

    memcpy(data_ + size_, data, size);
    size_ += size;
  }

  // For cleaing a block
  void Reset() {
    size_ = 0;
  }

  void Print() const {
    xoff_t pos = 0;
    for (size_t i = 0; i < Size(); i++) {
      if (pos % 16 == 0) {
	DP(RINT "%5"Q"x: ", pos);
      }
      DP(RINT "%02x ", (*this)[i]);
      if (pos % 16 == 15) {
	DP(RINT "\n");
      }
      pos++;
    }
    DP(RINT "\n");
  }

  void WriteTmpFile(TmpFile *f) const {
    f->Append(this);
  }

  void SetSize(size_t size) {
    size_ = size;

    if (data_size_ < size) {
      if (data_) {
	delete [] data_;
      }
      data_ = new uint8_t[size];
      data_size_ = size;
    }
  }
private:
  friend class BlockIterator;

  mutable uint8_t *data_;
  mutable size_t data_size_;
  size_t size_;
};

class FileSpec {
 public:
  FileSpec(MTRandom *rand)
    : rand_(rand) {
  }

  // Generates a file with a known size
  void GenerateFixedSize(xoff_t size) {
    Reset();

    for (xoff_t p = 0; p < size; ) {
      xoff_t t = min(Constants::BLOCK_SIZE, size - p);
      table_.insert(make_pair(p, Segment(t, rand_)));
      p += t;
    }
  }

  // Generates a file with exponential-random distributed size
  void GenerateRandomSize(xoff_t mean) {
    GenerateFixedSize(rand_->ExpRand(mean));
  }

  // Returns the size of the file
  xoff_t Size() const {
    if (table_.empty()) {
      return 0;
    }
    ConstSegmentMapIterator i = --table_.end();
    return i->first + i->second.Size();
  }

  // Returns the number of blocks
  xoff_t Blocks(size_t blksize = Constants::BLOCK_SIZE) const {
    if (table_.empty()) {
      return 0;
    }
    return ((Size() - 1) / blksize) + 1;
  }

  // Returns the number of segments
  xoff_t Segments() const {
    return table_.size();
  }

  // Create a mutation according to "what".
  void ModifyTo(const Mutator &mutator,
		FileSpec *modify) const {
    modify->Reset();
    mutator.Mutate(&modify->table_, &table_, rand_);
    modify->CheckSegments();
  }

  void CheckSegments() const {
    for (ConstSegmentMapIterator iter(table_.begin());
	 iter != table_.end(); ) {
      ConstSegmentMapIterator iter0(iter++);
      if (iter == table_.end()) {
	break;
      }
      CHECK_EQ(iter0->first + iter0->second.Size(), iter->first);
    }
  }

  void Reset() {
    table_.clear();
  }

  void Print() const {
    for (ConstSegmentMapIterator iter(table_.begin());
	 iter != table_.end();
	 ++iter) {
      const Segment &seg = iter->second;
      cerr << "Segment at " << iter->first
	   << " (" << seg.ToString() << ")" << endl;
    }
  }

  void PrintData() const {
    Block block;
    for (BlockIterator iter(*this); !iter.Done(); iter.Next()) {
      iter.Get(&block);
      block.Print();
    }
  }

  void WriteTmpFile(TmpFile *f) const {
    Block block;
    for (BlockIterator iter(*this); !iter.Done(); iter.Next()) {
      iter.Get(&block);
      f->Append(&block);
    }
  }

  void Get(Block *block, xoff_t offset, size_t size) const {
    size_t got = 0;
    block->SetSize(size);

    ConstSegmentMapIterator pos = table_.upper_bound(offset);
    if (pos == table_.begin()) {
      CHECK_EQ(0, Size());
      return;
    }
    --pos;

    while (got < size) {
      CHECK(pos != table_.end());
      CHECK_GE(offset, pos->first);

      const Segment &seg = pos->second;

      // The position of this segment may start before this block starts,
      // and then the position of the data may be offset from the seeding
      // position.
      size_t seg_offset = offset - pos->first;
      size_t advance = min(seg.Size() - seg_offset,
			   size - got);

      seg.Fill(seg_offset, advance, block->Data() + got);

      got += advance;
      offset += advance;
      ++pos;
    }
  }

  typedef BlockIterator iterator;

 private:
  friend class BlockIterator;

  MTRandom *rand_;
  SegmentMap table_;
};

class BlockIterator {
public:
  explicit BlockIterator(const FileSpec& spec)
    : spec_(spec),
      blkno_(0),
      blksize_(Constants::BLOCK_SIZE) { }

  BlockIterator(const FileSpec& spec,
		size_t blksize)
    : spec_(spec),
      blkno_(0),
      blksize_(blksize) { }

  bool Done() const {
    return blkno_ >= spec_.Blocks(blksize_);
  }

  void Next() {
    blkno_++;
  }

  xoff_t Blkno() const {
    return blkno_;
  }

  xoff_t Blocks() const {
    return spec_.Blocks(blksize_);
  }

  xoff_t Offset() const {
    return blkno_ * blksize_;
  }

  void SetBlock(xoff_t blkno) {
    blkno_ = blkno;
  }

  void Get(Block *block) const {
    spec_.Get(block, blkno_ * blksize_, BytesOnBlock());
  }

  size_t BytesOnBlock() const {
    xoff_t blocks = spec_.Blocks(blksize_);
    xoff_t size = spec_.Size();

    DCHECK((blkno_ < blocks) ||
	   (blkno_ == blocks && size % blksize_ == 0));

    if (blkno_ == blocks) {
      return 0;
    }
    if (blkno_ + 1 == blocks) {
      return ((size - 1) % blksize_) + 1;
    }
    return blksize_;
  }

  size_t BlockSize() const {
    return blksize_;
  }

private:
  const FileSpec& spec_;
  xoff_t blkno_;
  size_t blksize_;
};

class ExtFile {
public:
  ExtFile() {
    static int static_counter = 0;
    char buf[32];
    snprintf(buf, 32, "/tmp/regtest.%d", static_counter++);
    filename_.append(buf);
    unlink(filename_.c_str());
  }

  ~ExtFile() {
    unlink(filename_.c_str());
  }

  const char* Name() const {
    return filename_.c_str();
  }

  // Check whether a real file matches a file spec.
  bool EqualsSpec(const FileSpec &spec) const {
    main_file t;
    main_file_init(&t);
    CHECK_EQ(0, main_file_open(&t, Name(), XO_READ));

    Block tblock;
    Block sblock;
    for (BlockIterator iter(spec); !iter.Done(); iter.Next()) {
      iter.Get(&sblock);
      tblock.SetSize(sblock.Size());
      size_t tread;
      CHECK_EQ(0, main_file_read(&t,
				 tblock.Data(),
				 tblock.Size(), &tread, "read failed"));
      CHECK_EQ(0, CmpDifferentBlockBytes(tblock, sblock));
    }

    CHECK_EQ(0, main_file_close(&t));
    main_file_cleanup(&t);
    return true;
  }

protected:
  string filename_;
};

class TmpFile : public ExtFile {
public:
  TmpFile() {
    main_file_init(&file_);
    CHECK_EQ(0, main_file_open(&file_, Name(), XO_WRITE));
  }

  ~TmpFile() {
    main_file_cleanup(&file_);
  }

  void Append(const Block *block) {
    CHECK_EQ(0, main_file_write(&file_,
				block->Data(), block->Size(),
				"tmpfile write failed"));
  }

  const char* Name() const {
    if (main_file_isopen(&file_)) {
      CHECK_EQ(0, main_file_close(&file_));
    }
    return ExtFile::Name();
  }

private:
  mutable main_file file_;
};