extern "C" int32_t SystemNative_CopyFile(intptr_t sourceFd, intptr_t destinationFd)
{
int inFd = ToFileDescriptor(sourceFd);
int outFd = ToFileDescriptor(destinationFd);
#if HAVE_FCOPYFILE
// If fcopyfile is available (OS X), try to use it, as the whole copy
// can be performed in the kernel, without lots of unnecessary copying.
// Copy data and metadata.
return fcopyfile(inFd, outFd, nullptr, COPYFILE_ALL) == 0 ? 0 : -1;
#else
// Get the stats on the source file.
int ret;
struct stat_ sourceStat;
bool copied = false;
#if HAVE_SENDFILE
// If sendfile is available (Linux), try to use it, as the whole copy
// can be performed in the kernel, without lots of unnecessary copying.
while (CheckInterrupted(ret = fstat_(inFd, &sourceStat)));
if (ret != 0)
{
return -1;
}
// We use `auto' here to adapt the type of `size' depending on the running platform.
// On 32-bit, if you use 64-bit offsets, the last argument of `sendfile' will be a
// `size_t' a 32-bit integer while the `st_size' field of the stat structure will be off64_t.
// So `size' will have to be `uint64_t'. In all other cases, it will be `size_t'.
auto size = UnsignedCast(sourceStat.st_size);
// Note that per man page for large files, you have to iterate until the
// whole file is copied (Linux has a limit of 0x7ffff000 bytes copied).
while (size > 0)
{
ssize_t sent = sendfile(outFd, inFd, nullptr, (size >= SSIZE_MAX ? SSIZE_MAX : static_cast<size_t>(size)));
if (sent < 0)
{
if (errno != EINVAL && errno != ENOSYS)
{
return -1;
}
else
{
break;
}
}
else
{
assert(UnsignedCast(sent) <= size);
size -= UnsignedCast(sent);
}
}
if (size == 0)
{
copied = true;
}
// sendfile couldn't be used; fall back to a manual copy below. This could happen
// if we're on an old kernel, for example, where sendfile could only be used
// with sockets and not regular files.
#endif // HAVE_SENDFILE
// Manually read all data from the source and write it to the destination.
if (!copied && CopyFile_ReadWrite(inFd, outFd) != 0)
{
return -1;
}
// Now that the data from the file has been copied, copy over metadata
// from the source file. First copy the file times.
while (CheckInterrupted(ret = fstat_(inFd, &sourceStat)));
if (ret == 0)
{
struct timeval origTimes[2];
origTimes[0].tv_sec = sourceStat.st_atime;
origTimes[0].tv_usec = 0;
origTimes[1].tv_sec = sourceStat.st_mtime;
origTimes[1].tv_usec = 0;
while (CheckInterrupted(ret = futimes(outFd, origTimes)));
}
if (ret != 0)
{
return -1;
}
// Then copy permissions.
while (CheckInterrupted(ret = fchmod(outFd, sourceStat.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO))));
if (ret != 0)
{
return -1;
}
return 0;
#endif // HAVE_FCOPYFILE
}
int32_t SystemNative_CopyFile(intptr_t sourceFd, intptr_t destinationFd)
{
int inFd = ToFileDescriptor(sourceFd);
int outFd = ToFileDescriptor(destinationFd);
#if HAVE_FCOPYFILE
// If fcopyfile is available (OS X), try to use it, as the whole copy
// can be performed in the kernel, without lots of unnecessary copying.
// Copy data and metadata.
return fcopyfile(inFd, outFd, NULL, COPYFILE_ALL) == 0 ? 0 : -1;
#else
// Get the stats on the source file.
int ret;
struct stat_ sourceStat;
bool copied = false;
#if HAVE_SENDFILE_4
// If sendfile is available (Linux), try to use it, as the whole copy
// can be performed in the kernel, without lots of unnecessary copying.
while ((ret = fstat_(inFd, &sourceStat)) < 0 && errno == EINTR);
if (ret != 0)
{
return -1;
}
// On 32-bit, if you use 64-bit offsets, the last argument of `sendfile' will be a
// `size_t' a 32-bit integer while the `st_size' field of the stat structure will be off64_t.
// So `size' will have to be `uint64_t'. In all other cases, it will be `size_t'.
uint64_t size = (uint64_t)sourceStat.st_size;
// Note that per man page for large files, you have to iterate until the
// whole file is copied (Linux has a limit of 0x7ffff000 bytes copied).
while (size > 0)
{
ssize_t sent = sendfile(outFd, inFd, NULL, (size >= SSIZE_MAX ? SSIZE_MAX : (size_t)size));
if (sent < 0)
{
if (errno != EINVAL && errno != ENOSYS)
{
return -1;
}
else
{
break;
}
}
else
{
assert((size_t)sent <= size);
size -= (size_t)sent;
}
}
if (size == 0)
{
copied = true;
}
// sendfile couldn't be used; fall back to a manual copy below. This could happen
// if we're on an old kernel, for example, where sendfile could only be used
// with sockets and not regular files.
#endif // HAVE_SENDFILE_4
// Manually read all data from the source and write it to the destination.
if (!copied && CopyFile_ReadWrite(inFd, outFd) != 0)
{
return -1;
}
// Now that the data from the file has been copied, copy over metadata
// from the source file. First copy the file times.
// If futimes nor futimes are available on this platform, file times will
// not be copied over.
while ((ret = fstat_(inFd, &sourceStat)) < 0 && errno == EINTR);
if (ret == 0)
{
#if HAVE_FUTIMES
struct timeval origTimes[2];
origTimes[0].tv_sec = sourceStat.st_atime;
origTimes[0].tv_usec = ST_ATIME_NSEC(&sourceStat) / 1000;
origTimes[1].tv_sec = sourceStat.st_mtime;
origTimes[1].tv_usec = ST_MTIME_NSEC(&sourceStat) / 1000;
while ((ret = futimes(outFd, origTimes)) < 0 && errno == EINTR);
#elif HAVE_FUTIMENS
// futimes is not a POSIX function, and not available on Android,
// but futimens is
struct timespec origTimes[2];
origTimes[0].tv_sec = (time_t)sourceStat.st_atime;
origTimes[0].tv_nsec = ST_ATIME_NSEC(&sourceStat);
origTimes[1].tv_sec = (time_t)sourceStat.st_mtime;
origTimes[1].tv_nsec = ST_MTIME_NSEC(&sourceStat);
while ((ret = futimens(outFd, origTimes)) < 0 && errno == EINTR);
#endif
}
if (ret != 0)
{
return -1;
}
// Then copy permissions.
while ((ret = fchmod(outFd, sourceStat.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO))) < 0 && errno == EINTR);
if (ret != 0)
{
return -1;
}
return 0;
#endif // HAVE_FCOPYFILE
}