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//
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// 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.
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// 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
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "base/mmap.h"
#ifdef OS_WIN
#include <Windows.h>
#include <string>
#else
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#endif // OS_WIN
#include <cstring>
#include "base/logging.h"
#include "base/port.h"
#include "base/util.h"
#if defined(OS_WIN)
#include "base/scoped_handle.h"
#endif // OS_WIN
namespace mozc {
#if defined(OS_WIN)
Mmap::Mmap() : text_(nullptr), size_(0) {}
bool Mmap::Open(const char *filename, const char *mode) {
Close();
uint32 mode1, mode2, mode3, mode4;
if (strcmp(mode, "r") == 0) {
mode1 = GENERIC_READ;
mode2 = PAGE_READONLY;
mode3 = FILE_MAP_READ;
mode4 = FILE_SHARE_READ;
} else if (strcmp(mode, "r+") == 0) {
mode1 = GENERIC_READ | GENERIC_WRITE;
mode2 = PAGE_READWRITE;
mode3 = FILE_MAP_ALL_ACCESS;
mode4 = FILE_SHARE_READ | FILE_SHARE_WRITE;
} else {
LOG(ERROR) << "unknown open mode:" << filename;
return false;
}
std::wstring filename_wide;
if (Util::UTF8ToWide(filename, &filename_wide) <= 0) {
return false;
}
ScopedHandle handle(::CreateFileW(filename_wide.c_str(), mode1, mode4, 0,
OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0));
if (handle.get() == nullptr) {
LOG(ERROR) << "CreateFile() failed: " << filename;
return false;
}
ScopedHandle map_handle(::CreateFileMapping(handle.get(), 0, mode2, 0, 0, 0));
if (map_handle.get() == nullptr) {
LOG(ERROR) << "CreateFileMapping() failed: " << filename;
return false;
}
void *ptr = ::MapViewOfFile(map_handle.get(), mode3, 0, 0, 0);
if (ptr == nullptr) {
LOG(ERROR) << "MapViewOfFile() failed: " << filename;
return false;
}
text_ = reinterpret_cast<char *>(ptr);
size_ = ::GetFileSize(handle.get(), 0);
return true;
}
void Mmap::Close() {
if (text_ != nullptr) {
::UnmapViewOfFile(text_);
}
text_ = nullptr;
size_ = 0;
}
#else // !OS_WIN
Mmap::Mmap() : text_(nullptr), size_(0) {}
#ifndef O_BINARY
#define O_BINARY 0
#endif
namespace {
class ScopedCloser {
public:
explicit ScopedCloser(int fd) : fd_(fd) {}
~ScopedCloser() { ::close(fd_); }
private:
int fd_;
DISALLOW_COPY_AND_ASSIGN(ScopedCloser);
};
} // namespace
bool Mmap::Open(const char *filename, const char *mode) {
Close();
int flag;
if (strcmp(mode, "r") == 0) {
flag = O_RDONLY;
} else if (strcmp(mode, "r+") == 0) {
flag = O_RDWR;
} else {
LOG(WARNING) << "unknown open mode: " << filename;
return false;
}
int fd = ::open(filename, flag | O_BINARY);
if (fd < 0) {
LOG(WARNING) << "open failed: " << filename;
return false;
}
ScopedCloser closer(fd);
struct stat st;
if (fstat(fd, &st) < 0) {
LOG(WARNING) << "failed to get file size: " << filename;
return false;
}
int prot = PROT_READ;
if (flag == O_RDWR) {
prot |= PROT_WRITE;
}
void *ptr = mmap(nullptr, st.st_size, prot, MAP_SHARED, fd, 0);
if (ptr == MAP_FAILED) {
LOG(WARNING) << "mmap() failed: " << filename;
return false;
}
MaybeMLock(ptr, size_);
text_ = reinterpret_cast<char *>(ptr);
size_ = st.st_size;
return true;
}
void Mmap::Close() {
if (text_ != nullptr) {
MaybeMUnlock(text_, size_);
munmap(reinterpret_cast<char *>(text_), size_);
}
text_ = nullptr;
size_ = 0;
}
#endif // !OS_WIN
// Define a macro (MOZC_HAVE_MLOCK) to indicate mlock support.
// Caveat: Currently |OS_IOS| and |__APPLE__| are not exclusive.
#if defined(OS_ANDROID) || defined(OS_IOS) || defined(OS_NACL) || \
defined(OS_WIN)
#define MOZC_HAVE_MLOCK 0
#else // OS_ANDROID || OS_IOS || OS_NACL || OS_WIN
#define MOZC_HAVE_MLOCK 1
#endif // OS_ANDROID || OS_IOS || OS_NACL || OS_WIN
#ifndef MOZC_HAVE_MLOCK
#error "MOZC_HAVE_MLOCK is not defined"
#endif
#if MOZC_HAVE_MLOCK
bool Mmap::IsMLockSupported() { return true; }
int Mmap::MaybeMLock(const void *addr, size_t len) { return mlock(addr, len); }
int Mmap::MaybeMUnlock(const void *addr, size_t len) {
return munlock(addr, len);
}
#else // MOZC_HAVE_MLOCK
bool Mmap::IsMLockSupported() { return false; }
int Mmap::MaybeMLock(const void *addr, size_t len) { return -1; }
int Mmap::MaybeMUnlock(const void *addr, size_t len) { return -1; }
#endif // MOZC_HAVE_MLOCK
#undef MOZC_HAVE_MLOCK
} // namespace mozc