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Diffstat (limited to 'toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/line_reader.h')
-rw-r--r-- | toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/line_reader.h | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/line_reader.h b/toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/line_reader.h new file mode 100644 index 000000000..779cfeb60 --- /dev/null +++ b/toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/line_reader.h @@ -0,0 +1,131 @@ +// Copyright (c) 2009, 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. + +#ifndef CLIENT_LINUX_MINIDUMP_WRITER_LINE_READER_H_ +#define CLIENT_LINUX_MINIDUMP_WRITER_LINE_READER_H_ + +#include <stdint.h> +#include <assert.h> +#include <string.h> + +#include "common/linux/linux_libc_support.h" +#include "third_party/lss/linux_syscall_support.h" + +namespace google_breakpad { + +// A class for reading a file, line by line, without using fopen/fgets or other +// functions which may allocate memory. +class LineReader { + public: + LineReader(int fd) + : fd_(fd), + hit_eof_(false), + buf_used_(0) { + } + + // The maximum length of a line. + static const size_t kMaxLineLen = 512; + + // Return the next line from the file. + // line: (output) a pointer to the start of the line. The line is NUL + // terminated. + // len: (output) the length of the line (not inc the NUL byte) + // + // Returns true iff successful (false on EOF). + // + // One must call |PopLine| after this function, otherwise you'll continue to + // get the same line over and over. + bool GetNextLine(const char **line, unsigned *len) { + for (;;) { + if (buf_used_ == 0 && hit_eof_) + return false; + + for (unsigned i = 0; i < buf_used_; ++i) { + if (buf_[i] == '\n' || buf_[i] == 0) { + buf_[i] = 0; + *len = i; + *line = buf_; + return true; + } + } + + if (buf_used_ == sizeof(buf_)) { + // we scanned the whole buffer and didn't find an end-of-line marker. + // This line is too long to process. + return false; + } + + // We didn't find any end-of-line terminators in the buffer. However, if + // this is the last line in the file it might not have one: + if (hit_eof_) { + assert(buf_used_); + // There's room for the NUL because of the buf_used_ == sizeof(buf_) + // check above. + buf_[buf_used_] = 0; + *len = buf_used_; + buf_used_ += 1; // since we appended the NUL. + *line = buf_; + return true; + } + + // Otherwise, we should pull in more data from the file + const ssize_t n = sys_read(fd_, buf_ + buf_used_, + sizeof(buf_) - buf_used_); + if (n < 0) { + return false; + } else if (n == 0) { + hit_eof_ = true; + } else { + buf_used_ += n; + } + + // At this point, we have either set the hit_eof_ flag, or we have more + // data to process... + } + } + + void PopLine(unsigned len) { + // len doesn't include the NUL byte at the end. + + assert(buf_used_ >= len + 1); + buf_used_ -= len + 1; + my_memmove(buf_, buf_ + len + 1, buf_used_); + } + + private: + const int fd_; + + bool hit_eof_; + unsigned buf_used_; + char buf_[kMaxLineLen]; +}; + +} // namespace google_breakpad + +#endif // CLIENT_LINUX_MINIDUMP_WRITER_LINE_READER_H_ |