ssize_t
sendfile64 (int out_fd, int in_fd, off64_t *offset, size_t count)
{
sendfilevec64_t sfv;
sfv.sfv_fd = in_fd;
sfv.sfv_flag = 0;
sfv.sfv_off = *offset;
sfv.sfv_len = count;
size_t xferred = 0;
ssize_t res = sendfilev64 (out_fd, &sfv, 1, &xferred);
*offset += xferred;
return res;
}
ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T offset, size_t count)
{
int sfvcnt;
size_t total, xferred;
struct sendfilevec vec[2];
ssize_t hdr_len = 0;
if (header) {
sfvcnt = 2;
vec[0].sfv_fd = SFV_FD_SELF;
vec[0].sfv_flag = 0;
vec[0].sfv_off = (off_t)header->data;
vec[0].sfv_len = hdr_len = header->length;
vec[1].sfv_fd = fromfd;
vec[1].sfv_flag = 0;
vec[1].sfv_off = offset;
vec[1].sfv_len = count;
} else {
sfvcnt = 1;
vec[0].sfv_fd = fromfd;
vec[0].sfv_flag = 0;
vec[0].sfv_off = offset;
vec[0].sfv_len = count;
}
total = count + hdr_len;
while (total) {
ssize_t nwritten;
/*
* Although not listed in the API error returns, this is almost certainly
* a slow system call and will be interrupted by a signal with EINTR. JRA.
*/
xferred = 0;
#if defined(HAVE_EXPLICIT_LARGEFILE_SUPPORT) && defined(HAVE_OFF64_T) && defined(HAVE_SENDFILEV64)
nwritten = sendfilev64(tofd, vec, sfvcnt, &xferred);
#else
nwritten = sendfilev(tofd, vec, sfvcnt, &xferred);
#endif
if (nwritten == -1 && errno == EINTR) {
if (xferred == 0)
continue; /* Nothing written yet. */
else
nwritten = xferred;
}
if (nwritten == -1)
return -1;
if (nwritten == 0)
return -1; /* I think we're at EOF here... */
/*
* If this was a short (signal interrupted) write we may need
* to subtract it from the header data, or null out the header
* data altogether if we wrote more than vec[0].sfv_len bytes.
* We move vec[1].* to vec[0].* and set sfvcnt to 1
*/
if (sfvcnt == 2 && nwritten >= vec[0].sfv_len) {
vec[1].sfv_off += nwritten - vec[0].sfv_len;
vec[1].sfv_len -= nwritten - vec[0].sfv_len;
/* Move vec[1].* to vec[0].* and set sfvcnt to 1 */
vec[0] = vec[1];
sfvcnt = 1;
} else {
vec[0].sfv_off += nwritten;
vec[0].sfv_len -= nwritten;
}
total -= nwritten;
}
return count + hdr_len;
}
