Source code

Revision control

Copy as Markdown

Other Tools

// Copyright (c) 2013, 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_PROC_CPUINFO_READER_H_
#define CLIENT_LINUX_MINIDUMP_WRITER_PROC_CPUINFO_READER_H_
#include <stdint.h>
#include <assert.h>
#include <string.h>
#include "linux/minidump_writer/line_reader.h"
#include "common/linux/linux_libc_support.h"
#include "third_party/lss/linux_syscall_support.h"
namespace google_breakpad {
// A class for reading /proc/cpuinfo without using fopen/fgets or other
// functions which may allocate memory.
class ProcCpuInfoReader {
public:
ProcCpuInfoReader(int fd)
: line_reader_(fd), pop_count_(-1) {
}
// Return the next field name, or NULL in case of EOF.
// field: (output) Pointer to zero-terminated field name.
// Returns true on success, or false on EOF or error (line too long).
bool GetNextField(const char** field) {
for (;;) {
const char* line;
unsigned line_len;
// Try to read next line.
if (pop_count_ >= 0) {
line_reader_.PopLine(pop_count_);
pop_count_ = -1;
}
if (!line_reader_.GetNextLine(&line, &line_len))
return false;
pop_count_ = static_cast<int>(line_len);
const char* line_end = line + line_len;
// Expected format: <field-name> <space>+ ':' <space> <value>
// Note that:
// - empty lines happen.
// - <field-name> can contain spaces.
// - some fields have an empty <value>
char* sep = static_cast<char*>(my_memchr(line, ':', line_len));
if (sep == NULL)
continue;
// Record the value. Skip leading space after the column to get
// its start.
const char* val = sep+1;
while (val < line_end && my_isspace(*val))
val++;
value_ = val;
value_len_ = static_cast<size_t>(line_end - val);
// Remove trailing spaces before the column to properly 0-terminate
// the field name.
while (sep > line && my_isspace(sep[-1]))
sep--;
if (sep == line)
continue;
// zero-terminate field name.
*sep = '\0';
*field = line;
return true;
}
}
// Return the field value. This must be called after a succesful
// call to GetNextField().
const char* GetValue() {
assert(value_);
return value_;
}
// Same as GetValue(), but also returns the length in characters of
// the value.
const char* GetValueAndLen(size_t* length) {
assert(value_);
*length = value_len_;
return value_;
}
private:
LineReader line_reader_;
int pop_count_;
const char* value_;
size_t value_len_;
};
} // namespace google_breakpad
#endif // CLIENT_LINUX_MINIDUMP_WRITER_PROC_CPUINFO_READER_H_