/thirdparty/breakpad/client/minidump_file_writer.cc

  1// Copyright (c) 2006, Google Inc.
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  9// notice, this list of conditions and the following disclaimer.
 10//     * Redistributions in binary form must reproduce the above
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 12// in the documentation and/or other materials provided with the
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 16// this software without specific prior written permission.
 17//
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 24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 29
 30// minidump_file_writer.cc: Minidump file writer implementation.
 31//
 32// See minidump_file_writer.h for documentation.
 33
 34#include <fcntl.h>
 35#include <limits.h>
 36#include <stdio.h>
 37#include <string.h>
 38#include <unistd.h>
 39
 40#include "client/minidump_file_writer-inl.h"
 41#include "common/linux/linux_libc_support.h"
 42#include "common/string_conversion.h"
 43#if __linux__
 44#include "third_party/lss/linux_syscall_support.h"
 45#endif
 46
 47namespace google_breakpad {
 48
 49const MDRVA MinidumpFileWriter::kInvalidMDRVA = static_cast<MDRVA>(-1);
 50
 51MinidumpFileWriter::MinidumpFileWriter() : file_(-1), position_(0), size_(0) {
 52}
 53
 54MinidumpFileWriter::~MinidumpFileWriter() {
 55  Close();
 56}
 57
 58bool MinidumpFileWriter::Open(const char *path) {
 59  assert(file_ == -1);
 60#if __linux__
 61  file_ = sys_open(path, O_WRONLY | O_CREAT | O_EXCL, 0600);
 62#else
 63  file_ = open(path, O_WRONLY | O_CREAT | O_EXCL, 0600);
 64#endif
 65
 66  return file_ != -1;
 67}
 68
 69bool MinidumpFileWriter::Close() {
 70  bool result = true;
 71
 72  if (file_ != -1) {
 73    if (-1 == ftruncate(file_, position_)) {
 74       return false;
 75    }
 76#if __linux__
 77    result = (sys_close(file_) == 0);
 78#else
 79    result = (close(file_) == 0);
 80#endif
 81    file_ = -1;
 82  }
 83
 84  return result;
 85}
 86
 87bool MinidumpFileWriter::CopyStringToMDString(const wchar_t *str,
 88                                              unsigned int length,
 89                                              TypedMDRVA<MDString> *mdstring) {
 90  bool result = true;
 91  if (sizeof(wchar_t) == sizeof(u_int16_t)) {
 92    // Shortcut if wchar_t is the same size as MDString's buffer
 93    result = mdstring->Copy(str, mdstring->get()->length);
 94  } else {
 95    u_int16_t out[2];
 96    int out_idx = 0;
 97
 98    // Copy the string character by character
 99    while (length && result) {
100      UTF32ToUTF16Char(*str, out);
101      if (!out[0])
102        return false;
103
104      // Process one character at a time
105      --length;
106      ++str;
107
108      // Append the one or two UTF-16 characters.  The first one will be non-
109      // zero, but the second one may be zero, depending on the conversion from
110      // UTF-32.
111      int out_count = out[1] ? 2 : 1;
112      size_t out_size = sizeof(u_int16_t) * out_count;
113      result = mdstring->CopyIndexAfterObject(out_idx, out, out_size);
114      out_idx += out_count;
115    }
116  }
117  return result;
118}
119
120bool MinidumpFileWriter::CopyStringToMDString(const char *str,
121                                              unsigned int length,
122                                              TypedMDRVA<MDString> *mdstring) {
123  bool result = true;
124  u_int16_t out[2];
125  int out_idx = 0;
126
127  // Copy the string character by character
128  while (length && result) {
129    int conversion_count = UTF8ToUTF16Char(str, length, out);
130    if (!conversion_count)
131      return false;
132
133    // Move the pointer along based on the nubmer of converted characters
134    length -= conversion_count;
135    str += conversion_count;
136
137    // Append the one or two UTF-16 characters
138    int out_count = out[1] ? 2 : 1;
139    size_t out_size = sizeof(u_int16_t) * out_count;
140    result = mdstring->CopyIndexAfterObject(out_idx, out, out_size);
141    out_idx += out_count;
142  }
143  return result;
144}
145
146template <typename CharType>
147bool MinidumpFileWriter::WriteStringCore(const CharType *str,
148                                         unsigned int length,
149                                         MDLocationDescriptor *location) {
150  assert(str);
151  assert(location);
152  // Calculate the mdstring length by either limiting to |length| as passed in
153  // or by finding the location of the NULL character.
154  unsigned int mdstring_length = 0;
155  if (!length)
156    length = INT_MAX;
157  for (; mdstring_length < length && str[mdstring_length]; ++mdstring_length)
158    ;
159
160  // Allocate the string buffer
161  TypedMDRVA<MDString> mdstring(this);
162  if (!mdstring.AllocateObjectAndArray(mdstring_length + 1, sizeof(u_int16_t)))
163    return false;
164
165  // Set length excluding the NULL and copy the string
166  mdstring.get()->length =
167      static_cast<u_int32_t>(mdstring_length * sizeof(u_int16_t));
168  bool result = CopyStringToMDString(str, mdstring_length, &mdstring);
169
170  // NULL terminate
171  if (result) {
172    u_int16_t ch = 0;
173    result = mdstring.CopyIndexAfterObject(mdstring_length, &ch, sizeof(ch));
174
175    if (result)
176      *location = mdstring.location();
177  }
178
179  return result;
180}
181
182bool MinidumpFileWriter::WriteString(const wchar_t *str, unsigned int length,
183                 MDLocationDescriptor *location) {
184  return WriteStringCore(str, length, location);
185}
186
187bool MinidumpFileWriter::WriteString(const char *str, unsigned int length,
188                 MDLocationDescriptor *location) {
189  return WriteStringCore(str, length, location);
190}
191
192bool MinidumpFileWriter::WriteMemory(const void *src, size_t size,
193                                     MDMemoryDescriptor *output) {
194  assert(src);
195  assert(output);
196  UntypedMDRVA mem(this);
197
198  if (!mem.Allocate(size))
199    return false;
200  if (!mem.Copy(src, mem.size()))
201    return false;
202
203  output->start_of_memory_range = reinterpret_cast<u_int64_t>(src);
204  output->memory = mem.location();
205
206  return true;
207}
208
209MDRVA MinidumpFileWriter::Allocate(size_t size) {
210  assert(size);
211  assert(file_ != -1);
212  size_t aligned_size = (size + 7) & ~7;  // 64-bit alignment
213
214  if (position_ + aligned_size > size_) {
215    size_t growth = aligned_size;
216    size_t minimal_growth = getpagesize();
217
218    // Ensure that the file grows by at least the size of a memory page
219    if (growth < minimal_growth)
220      growth = minimal_growth;
221
222    size_t new_size = size_ + growth;
223    if (ftruncate(file_, new_size) != 0)
224      return kInvalidMDRVA;
225
226    size_ = new_size;
227  }
228
229  MDRVA current_position = position_;
230  position_ += static_cast<MDRVA>(aligned_size);
231
232  return current_position;
233}
234
235bool MinidumpFileWriter::Copy(MDRVA position, const void *src, ssize_t size) {
236  assert(src);
237  assert(size);
238  assert(file_ != -1);
239
240  // Ensure that the data will fit in the allocated space
241  if (static_cast<size_t>(size + position) > size_)
242    return false;
243
244  // Seek and write the data
245#if __linux__
246  if (sys_lseek(file_, position, SEEK_SET) == static_cast<off_t>(position)) {
247    if (sys_write(file_, src, size) == size) {
248#else
249  if (lseek(file_, position, SEEK_SET) == static_cast<off_t>(position)) {
250    if (write(file_, src, size) == size) {
251#endif
252      return true;
253    }
254  }
255
256  return false;
257}
258
259bool UntypedMDRVA::Allocate(size_t size) {
260  assert(size_ == 0);
261  size_ = size;
262  position_ = writer_->Allocate(size_);
263  return position_ != MinidumpFileWriter::kInvalidMDRVA;
264}
265
266bool UntypedMDRVA::Copy(MDRVA pos, const void *src, size_t size) {
267  assert(src);
268  assert(size);
269  assert(pos + size <= position_ + size_);
270  return writer_->Copy(pos, src, size);
271}
272
273}  // namespace google_breakpad