diff options
Diffstat (limited to 'sysdeps/mach/hurd/sendfile64.c')
| -rw-r--r-- | sysdeps/mach/hurd/sendfile64.c | 41 |
1 files changed, 29 insertions, 12 deletions
diff --git a/sysdeps/mach/hurd/sendfile64.c b/sysdeps/mach/hurd/sendfile64.c index 40ce271efb..1f63d2a2f5 100644 --- a/sysdeps/mach/hurd/sendfile64.c +++ b/sysdeps/mach/hurd/sendfile64.c @@ -18,26 +18,43 @@ 02111-1307 USA. */ #include <sys/sendfile.h> -#include <errno.h> -#include <stddef.h> +#include <hurd.h> +#include <hurd/fd.h> +#include <sys/mman.h> /* Send COUNT bytes from file associated with IN_FD starting at OFFSET to descriptor OUT_FD. */ ssize_t sendfile64 (int out_fd, int in_fd, off64_t *offset, size_t count) { - if (offset == NULL) - return sendfile (out_fd, in_fd, NULL, count); - else + /* We just do a vanilla io_read followed by a vanilla io_write here. + In theory the IN_FD filesystem can return us out-of-line data that + we then send out-of-line to the OUT_FD filesystem and no copying + takes place until those pages need to be flushed or packaged by + that filesystem (e.g. packetized by a network socket). However, + we momentarily consume COUNT bytes of our local address space, + which might blow if it's huge or address space is real tight. */ + + char *data = 0; + size_t datalen = 0; + error_t err = HURD_DPORT_USE (in_fd, + __io_read (port, &data, &datalen, + offset ? *offset : (off_t) -1, + count)); + if (err == 0) { - off_t ofs = *offset; - if (ofs != *offset) + size_t nwrote; + if (datalen == 0) + return 0; + err = HURD_DPORT_USE (out_fd, __io_write (port, data, datalen, + (off_t) -1, &nwrote)); + munmap (data, datalen); + if (err == 0) { - __set_errno (EOVERFLOW); - return -1; + if (offset) + *offset += datalen; + return nwrote; } - ssize_t ret = sendfile (out_fd, in_fd, &ofs, count); - *offset = ofs; - return ret; } + return __hurd_fail (err); } |