#include "guestfs-internal-actions.h"
#include "guestfs_protocol.h"
+/* Size of guestfs_progress message on the wire. */
+#define PROGRESS_MESSAGE_SIZE 24
+
/* This is the code used to send and receive RPC messages and (for
* certain types of message) to perform file transfers. This code is
* driven from the generated actions (src/actions.c). There
return 0;
}
+/* Read 'n' bytes, setting the socket to blocking temporarily so
+ * that we really read the number of bytes requested.
+ * Returns: 0 == EOF while reading
+ * -1 == error, error() function has been called
+ * n == read 'n' bytes in full
+ */
+static ssize_t
+really_read_from_socket (guestfs_h *g, int sock, char *buf, size_t n)
+{
+ long flags;
+ ssize_t r;
+ size_t got;
+
+ /* Set socket to blocking. */
+ flags = fcntl (sock, F_GETFL);
+ if (flags == -1) {
+ perrorf (g, "fcntl");
+ return -1;
+ }
+ if (fcntl (sock, F_SETFL, flags & ~O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ return -1;
+ }
+
+ got = 0;
+ while (got < n) {
+ r = read (sock, &buf[got], n-got);
+ if (r == -1) {
+ perrorf (g, "read");
+ return -1;
+ }
+ if (r == 0)
+ return 0; /* EOF */
+ got += r;
+ }
+
+ /* Restore original socket flags. */
+ if (fcntl (sock, F_SETFL, flags) == -1) {
+ perrorf (g, "fcntl");
+ return -1;
+ }
+
+ return (ssize_t) got;
+}
+
static int
check_for_daemon_cancellation_or_eof (guestfs_h *g, int fd)
{
char buf[4];
- int n;
+ ssize_t n;
uint32_t flag;
XDR xdr;
"check_for_daemon_cancellation_or_eof: %p g->state = %d, fd = %d\n",
g, g->state, fd);
- n = read (fd, buf, 4);
+ n = really_read_from_socket (g, fd, buf, 4);
+ if (n == -1)
+ return -1;
if (n == 0) {
/* Hopefully this indicates the qemu child process has died. */
child_cleanup (g);
return -1;
}
- if (n == -1) {
- if (errno == EINTR || errno == EAGAIN)
- return 0;
-
- perrorf (g, "read");
- return -1;
- }
-
xdrmem_create (&xdr, buf, 4, XDR_DECODE);
xdr_uint32_t (&xdr, &flag);
xdr_destroy (&xdr);
+ /* Read and process progress messages that happen during FileIn. */
+ if (flag == GUESTFS_PROGRESS_FLAG) {
+ char buf[PROGRESS_MESSAGE_SIZE];
+
+ n = really_read_from_socket (g, fd, buf, PROGRESS_MESSAGE_SIZE);
+ if (n == -1)
+ return -1;
+ if (n == 0) {
+ child_cleanup (g);
+ return -1;
+ }
+
+ if (g->state == BUSY && g->progress_cb) {
+ guestfs_progress message;
+
+ xdrmem_create (&xdr, buf, PROGRESS_MESSAGE_SIZE, XDR_DECODE);
+ xdr_guestfs_progress (&xdr, &message);
+ xdr_destroy (&xdr);
+
+ g->progress_cb (g, g->progress_cb_data,
+ message.proc, message.serial,
+ message.position, message.total);
+ }
+
+ return 0;
+ }
+
if (flag != GUESTFS_CANCEL_FLAG) {
error (g, _("check_for_daemon_cancellation_or_eof: read 0x%x from daemon, expected 0x%x\n"),
flag, GUESTFS_CANCEL_FLAG);
}
if (FD_ISSET (g->sock, &rset2)) {
r = check_for_daemon_cancellation_or_eof (g, g->sock);
- if (r < 0)
- return r;
+ if (r == -1)
+ return r;
+ if (r == -2) {
+ /* Daemon sent cancel message. But to maintain
+ * synchronization we must write out the remainder of the
+ * write buffer before we return (RHBZ#576879).
+ */
+ if (xwrite (g->sock, buf, n) == -1) {
+ perrorf (g, "write");
+ return -1;
+ }
+ return -2; /* cancelled */
+ }
}
if (FD_ISSET (g->sock, &wset2)) {
r = write (g->sock, buf, n);
* will not see GUESTFS_PROGRESS_FLAG.
*/
-/* Size of guestfs_progress message on the wire. */
-#define PROGRESS_MESSAGE_SIZE 24
+static inline void
+unexpected_end_of_file_from_daemon_error (guestfs_h *g)
+{
+#define UNEXPEOF_ERROR "unexpected end of file when reading from daemon.\n"
+#define UNEXPEOF_TEST_TOOL \
+ "Or you can run 'libguestfs-test-tool' and post the complete output into\n" \
+ "a bug report or message to the libguestfs mailing list."
+ if (!g->verbose)
+ error (g, _(UNEXPEOF_ERROR
+"This usually means the libguestfs appliance failed to start up. Please\n"
+"enable debugging (LIBGUESTFS_DEBUG=1) and rerun the command, then look at\n"
+"the debug messages output prior to this error.\n"
+UNEXPEOF_TEST_TOOL));
+ else
+ error (g, _(UNEXPEOF_ERROR
+"See earlier debug messages.\n"
+UNEXPEOF_TEST_TOOL));
+}
int
guestfs___recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn)
return -1;
}
if (r == 0) {
- error (g, _("unexpected end of file when reading from daemon"));
+ unexpected_end_of_file_from_daemon_error (g);
child_cleanup (g);
return -1;
}
return -1;
}
if (r == 0) {
- error (g, _("unexpected end of file when reading from daemon"));
+ unexpected_end_of_file_from_daemon_error (g);
child_cleanup (g);
free (*buf_rtn);
*buf_rtn = NULL;
}
int
-guestfs___send (guestfs_h *g, int proc_nr, xdrproc_t xdrp, char *args)
+guestfs___send (guestfs_h *g, int proc_nr,
+ uint64_t progress_hint, uint64_t optargs_bitmask,
+ xdrproc_t xdrp, char *args)
{
struct guestfs_message_header hdr;
XDR xdr;
hdr.direction = GUESTFS_DIRECTION_CALL;
hdr.serial = serial;
hdr.status = GUESTFS_STATUS_OK;
- hdr.progress_hint = 0;
- hdr.optargs_bitmask = 0;
+ hdr.progress_hint = progress_hint;
+ hdr.optargs_bitmask = optargs_bitmask;
if (!xdr_guestfs_message_header (&xdr, &hdr)) {
error (g, _("xdr_guestfs_message_header failed"));
if (fd == -1) {
perrorf (g, "open: %s", filename);
send_file_cancellation (g);
- /* Daemon sees cancellation and won't reply, so caller can
- * just return here.
- */
return -1;
}
return 0;
}
+/* Same as guestfs___recv, but it discards the reply message. */
+int
+guestfs___recv_discard (guestfs_h *g, const char *fn)
+{
+ void *buf;
+ uint32_t size;
+ int r;
+
+ again:
+ r = guestfs___recv_from_daemon (g, &size, &buf);
+ if (r == -1)
+ return -1;
+
+ /* This can happen if a cancellation happens right at the end
+ * of us sending a FileIn parameter to the daemon. Discard. The
+ * daemon should send us an error message next.
+ */
+ if (size == GUESTFS_CANCEL_FLAG)
+ goto again;
+
+ if (size == GUESTFS_LAUNCH_FLAG) {
+ error (g, "%s: received unexpected launch flag from daemon when expecting reply", fn);
+ return -1;
+ }
+
+ return 0;
+}
+
/* Receive a file. */
/* Returns -1 = error, 0 = EOF, > 0 = more data */