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 // Copyright (c) 2006, Google Inc.

 // All rights reserved.

 //

 // Redistribution and use in source and binary forms, with or without

 // modification, are permitted provided that the following conditions are

 // met:

 //

 //     * Redistributions of source code must retain the above copyright

 // notice, this list of conditions and the following disclaimer.

 //     * Redistributions in binary form must reproduce the above

 // copyright notice, this list of conditions and the following disclaimer

 // in the documentation and/or other materials provided with the

 // distribution.

 //     * Neither the name of Google Inc. nor the names of its

 // contributors may be used to endorse or promote products derived from

 // this software without specific prior written permission.

 //

 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 // minidump_file_writer.cc: Minidump file writer implementation.

 //

 // See minidump_file_writer.h for documentation.

 #include <fcntl.h>

 #include <limits.h>

 #include <stdio.h>

 #include <string.h>

 #include <unistd.h>

 #include "client/minidump_file_writer-inl.h"

 #include "common/linux/linux_libc_support.h"

 #include "common/string_conversion.h"

 #if __linux__

 #include "third_party/lss/linux_syscall_support.h"

 #endif

 namespace google_breakpad {

 const MDRVA MinidumpFileWriter::kInvalidMDRVA = static_cast<MDRVA>(-1);

 MinidumpFileWriter::MinidumpFileWriter()

     : file_(-1),

       close_file_when_destroyed_(true),

       position_(0),

       size_(0) {

 }

 MinidumpFileWriter::~MinidumpFileWriter() {

   if (close_file_when_destroyed_)

     Close();

 }

 bool MinidumpFileWriter::Open(const char *path) {

   assert(file_ == -1);

 #if __linux__

   file_ = sys_open(path, O_WRONLY | O_CREAT | O_EXCL, 0600);

 #else

   file_ = open(path, O_WRONLY | O_CREAT | O_EXCL, 0600);

 #endif

   return file_ != -1;

 }

 void MinidumpFileWriter::SetFile(const int file) {

   assert(file_ == -1);

   file_ = file;

   close_file_when_destroyed_ = false;

 }

 bool MinidumpFileWriter::Close() {

   bool result = true;

   if (file_ != -1) {

     if (-1 == ftruncate(file_, position_)) {

        return false;

     }

 #if __linux__

     result = (sys_close(file_) == 0);

 #else

     result = (close(file_) == 0);

 #endif

     file_ = -1;

   }

   return result;

 }

 bool MinidumpFileWriter::CopyStringToMDString(const wchar_t *str,

                                               unsigned int length,

                                               TypedMDRVA<MDString> *mdstring) {

   bool result = true;

   if (sizeof(wchar_t) == sizeof(uint16_t)) {

     // Shortcut if wchar_t is the same size as MDString's buffer

     result = mdstring->Copy(str, mdstring->get()->length);

   } else {

     uint16_t out[2];

     int out_idx = 0;

     // Copy the string character by character

     while (length && result) {

       UTF32ToUTF16Char(*str, out);

       if (!out[0])

         return false;

       // Process one character at a time

       --length;

       ++str;

       // Append the one or two UTF-16 characters.  The first one will be non-

       // zero, but the second one may be zero, depending on the conversion from

       // UTF-32.

       int out_count = out[1] ? 2 : 1;

       size_t out_size = sizeof(uint16_t) * out_count;

       result = mdstring->CopyIndexAfterObject(out_idx, out, out_size);

       out_idx += out_count;

     }

   }

   return result;

 }

 bool MinidumpFileWriter::CopyStringToMDString(const char *str,

                                               unsigned int length,

                                               TypedMDRVA<MDString> *mdstring) {

   bool result = true;

   uint16_t out[2];

   int out_idx = 0;

   // Copy the string character by character

   while (length && result) {

     int conversion_count = UTF8ToUTF16Char(str, length, out);

     if (!conversion_count)

       return false;

     // Move the pointer along based on the nubmer of converted characters

     length -= conversion_count;

     str += conversion_count;

     // Append the one or two UTF-16 characters

     int out_count = out[1] ? 2 : 1;

     size_t out_size = sizeof(uint16_t) * out_count;

     result = mdstring->CopyIndexAfterObject(out_idx, out, out_size);

     out_idx += out_count;

   }

   return result;

 }

 template <typename CharType>

 bool MinidumpFileWriter::WriteStringCore(const CharType *str,

                                          unsigned int length,

                                          MDLocationDescriptor *location) {

   assert(str);

   assert(location);

   // Calculate the mdstring length by either limiting to |length| as passed in

   // or by finding the location of the NULL character.

   unsigned int mdstring_length = 0;

   if (!length)

     length = INT_MAX;

   for (; mdstring_length < length && str[mdstring_length]; ++mdstring_length)

     ;

   // Allocate the string buffer

   TypedMDRVA<MDString> mdstring(this);

   if (!mdstring.AllocateObjectAndArray(mdstring_length + 1, sizeof(uint16_t)))

     return false;

   // Set length excluding the NULL and copy the string

   mdstring.get()->length =

       static_cast<uint32_t>(mdstring_length * sizeof(uint16_t));

   bool result = CopyStringToMDString(str, mdstring_length, &mdstring);

   // NULL terminate

   if (result) {

     uint16_t ch = 0;

     result = mdstring.CopyIndexAfterObject(mdstring_length, &ch, sizeof(ch));

     if (result)

       *location = mdstring.location();

   }

   return result;

 }

 bool MinidumpFileWriter::WriteString(const wchar_t *str, unsigned int length,

                  MDLocationDescriptor *location) {

   return WriteStringCore(str, length, location);

 }

 bool MinidumpFileWriter::WriteString(const char *str, unsigned int length,

                  MDLocationDescriptor *location) {

   return WriteStringCore(str, length, location);

 }

 bool MinidumpFileWriter::WriteMemory(const void *src, size_t size,

                                      MDMemoryDescriptor *output) {

   assert(src);

   assert(output);

   UntypedMDRVA mem(this);

   if (!mem.Allocate(size))

     return false;

   if (!mem.Copy(src, mem.size()))

     return false;

   output->start_of_memory_range = reinterpret_cast<uint64_t>(src);

   output->memory = mem.location();

   return true;

 }

 MDRVA MinidumpFileWriter::Allocate(size_t size) {

   assert(size);

   assert(file_ != -1);

   size_t aligned_size = (size + 7) & ~7;  // 64-bit alignment

   if (position_ + aligned_size > size_) {

     size_t growth = aligned_size;

     size_t minimal_growth = getpagesize();

     // Ensure that the file grows by at least the size of a memory page

     if (growth < minimal_growth)

       growth = minimal_growth;

     size_t new_size = size_ + growth;

     if (ftruncate(file_, new_size) != 0)

       return kInvalidMDRVA;

     size_ = new_size;

   }

   MDRVA current_position = position_;

   position_ += static_cast<MDRVA>(aligned_size);

   return current_position;

 }

 bool MinidumpFileWriter::Copy(MDRVA position, const void *src, ssize_t size) {

   assert(src);

   assert(size);

   assert(file_ != -1);

   // Ensure that the data will fit in the allocated space

   if (static_cast<size_t>(size + position) > size_)

     return false;

   // Seek and write the data

 #if __linux__

   if (sys_lseek(file_, position, SEEK_SET) == static_cast<off_t>(position)) {

     if (sys_write(file_, src, size) == size) {

 #else

   if (lseek(file_, position, SEEK_SET) == static_cast<off_t>(position)) {

     if (write(file_, src, size) == size) {

 #endif

       return true;

     }

   }

   return false;

 }

 bool UntypedMDRVA::Allocate(size_t size) {

   assert(size_ == 0);

   size_ = size;

   position_ = writer_->Allocate(size_);

   return position_ != MinidumpFileWriter::kInvalidMDRVA;

 }

 bool UntypedMDRVA::Copy(MDRVA pos, const void *src, size_t size) {

   assert(src);

   assert(size);

   assert(pos + size <= position_ + size_);

   return writer_->Copy(pos, src, size);

 }

 }  // namespace google_breakpad