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// 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_HANDLE_DIRECTORY_READER_H_
#define CLIENT_LINUX_HANDLE_DIRECTORY_READER_H_
#include <stdint.h>
#include <unistd.h>
#include <limits.h>
#include <assert.h>
#include <errno.h>
#include <string.h>
#include "breakpad/linux/linux_syscall_support.h"
namespace google_breakpad {
// A class for enumerating a directory without using diropen/readdir or other
// functions which may allocate memory.
class DirectoryReader {
public:
DirectoryReader(int fd)
: fd_(fd),
buf_used_(0) {
}
// Return the next entry from the directory
// name: (output) the NUL terminated entry name
//
// Returns true iff successful (false on EOF).
//
// After calling this, one must call |PopEntry| otherwise you'll get the same
// entry over and over.
bool GetNextEntry(const char** name) {
struct kernel_dirent* const dent =
reinterpret_cast<kernel_dirent*>(buf_);
if (buf_used_ == 0) {
// need to read more entries.
const int n = sys_getdents(fd_, dent, sizeof(buf_));
if (n < 0) {
return false;
} else if (n == 0) {
hit_eof_ = true;
} else {
buf_used_ += n;
}
}
if (buf_used_ == 0 && hit_eof_)
return false;
assert(buf_used_ > 0);
*name = dent->d_name;
return true;
}
void PopEntry() {
if (!buf_used_)
return;
const struct kernel_dirent* const dent =
reinterpret_cast<kernel_dirent*>(buf_);
buf_used_ -= dent->d_reclen;
memmove(buf_, buf_ + dent->d_reclen, buf_used_);
}
private:
const int fd_;
bool hit_eof_;
unsigned buf_used_;
uint8_t buf_[sizeof(struct kernel_dirent) + NAME_MAX + 1];
};
} // namespace google_breakpad
#endif // CLIENT_LINUX_HANDLE_DIRECTORY_READER_H_
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