static ssize_t uv__fs_write(uv_fs_t* req) {
#if defined(__linux__)
static int no_pwritev;
#endif
ssize_t r;
/* Serialize writes on OS X, concurrent write() and pwrite() calls result in
* data loss. We can't use a per-file descriptor lock, the descriptor may be
* a dup().
*/
#if defined(__APPLE__)
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
if (pthread_mutex_lock(&lock))
abort();
#endif
if (req->off < 0) {
if (req->nbufs == 1)
r = write(req->file, req->bufs[0].base, req->bufs[0].len);
else
r = writev(req->file, (struct iovec*) req->bufs, req->nbufs);
} else {
if (req->nbufs == 1) {
r = pwrite(req->file, req->bufs[0].base, req->bufs[0].len, req->off);
goto done;
}
#if HAVE_PREADV
r = pwritev(req->file, (struct iovec*) req->bufs, req->nbufs, req->off);
#else
# if defined(__linux__)
if (no_pwritev) retry:
# endif
{
r = pwrite(req->file, req->bufs[0].base, req->bufs[0].len, req->off);
}
# if defined(__linux__)
else {
r = uv__pwritev(req->file,
(struct iovec*) req->bufs,
req->nbufs,
req->off);
if (r == -1 && errno == ENOSYS) {
no_pwritev = 1;
goto retry;
}
}
# endif
#endif
}
done:
#if defined(__APPLE__)
if (pthread_mutex_unlock(&lock))
abort();
#endif
return r;
}
static ssize_t uv__fs_write(uv_fs_t* req) {
ssize_t r;
/* Serialize writes on OS X, concurrent write() and pwrite() calls result in
* data loss. We can't use a per-file descriptor lock, the descriptor may be
* a dup().
*/
#if defined(__APPLE__)
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_lock(&lock);
#endif
if (req->off < 0) {
if (req->nbufs == 1)
r = write(req->file, req->bufs[0].base, req->bufs[0].len);
else
r = writev(req->file, (struct iovec*) req->bufs, req->nbufs);
} else {
if (req->nbufs == 1) {
r = pwrite(req->file, req->bufs[0].base, req->bufs[0].len, req->off);
goto done;
}
#if HAVE_PREADV
r = pwritev(req->file, (struct iovec*) req->bufs, req->nbufs, req->off);
#else
# if defined(__linux__)
static int no_pwritev;
if (no_pwritev)
# endif
{
off_t written;
size_t index;
# if defined(__linux__)
retry:
# endif
written = 0;
index = 0;
r = 0;
do {
if (req->bufs[index].len > 0) {
r = pwrite(req->file,
req->bufs[index].base,
req->bufs[index].len,
req->off + written);
if (r > 0)
written += r;
}
index++;
} while (index < req->nbufs && r >= 0);
if (written > 0)
r = written;
}
# if defined(__linux__)
else {
r = uv__pwritev(req->file,
(struct iovec*) req->bufs,
req->nbufs,
req->off);
if (r == -1 && errno == ENOSYS) {
no_pwritev = 1;
goto retry;
}
}
# endif
#endif
}
done:
#if defined(__APPLE__)
pthread_mutex_unlock(&lock);
#endif
if (req->bufs != req->bufsml)
free(req->bufs);
return r;
}
