#endif
#include "guestfs.h"
+#include "guestfs_protocol.h"
static void error (guestfs_h *g, const char *fs, ...);
static void perrorf (guestfs_h *g, const char *fs, ...);
static void default_error_cb (guestfs_h *g, void *data, const char *msg);
static void stdout_event (void *data, int watch, int fd, int events);
static void sock_read_event (void *data, int watch, int fd, int events);
-//static void sock_write_event (void *data, int watch, int fd, int events);
+static void sock_write_event (void *data, int watch, int fd, int events);
+
+static void close_handles (void);
static int select_add_handle (guestfs_h *g, int fd, int events, guestfs_handle_event_cb cb, void *data);
static int select_remove_handle (guestfs_h *g, int watch);
struct guestfs_h
{
+ struct guestfs_h *next; /* Linked list of open handles. */
+
/* State: see the state machine diagram in the man page guestfs(3). */
enum state state;
char *msg_in;
int msg_in_size, msg_in_allocated;
char *msg_out;
- int msg_out_size;
+ int msg_out_size, msg_out_pos;
+
+ int msg_next_serial;
};
+static guestfs_h *handles = NULL;
+static int atexit_handler_set = 0;
+
guestfs_h *
guestfs_create (void)
{
str = getenv ("LIBGUESTFS_DEBUG");
g->verbose = str != NULL && strcmp (str, "1") == 0;
+ /* Start with large serial numbers so they are easy to spot
+ * inside the protocol.
+ */
+ g->msg_next_serial = 0x00123400;
+
+ /* Link the handles onto a global list. This is the one area
+ * where the library needs to be made thread-safe. (XXX)
+ */
+ /* acquire mutex (XXX) */
+ g->next = handles;
+ handles = g;
+ if (!atexit_handler_set) {
+ atexit (close_handles);
+ atexit_handler_set = 1;
+ }
+ /* release mutex (XXX) */
+
+ if (g->verbose)
+ fprintf (stderr, "new guestfs handle %p\n", g);
+
return g;
}
{
int i;
char filename[256];
+ guestfs_h *gg;
if (g->state == NO_HANDLE) {
/* Not safe to call 'error' here, so ... */
return;
}
+ if (g->verbose)
+ fprintf (stderr, "closing guestfs handle %p (state %d)\n", g, g->state);
+
/* Remove any handlers that might be called back before we kill the
* subprocess.
*/
/* Mark the handle as dead before freeing it. */
g->state = NO_HANDLE;
+ /* acquire mutex (XXX) */
+ if (handles == g)
+ handles = g->next;
+ else {
+ for (gg = handles; gg->next != g; gg = gg->next)
+ ;
+ gg->next = g->next;
+ }
+ /* release mutex (XXX) */
+
free (g);
}
+/* Close all open handles (called from atexit(3)). */
+static void
+close_handles (void)
+{
+ while (handles) guestfs_close (handles);
+}
+
static void
default_error_cb (guestfs_h *g, void *data, const char *msg)
{
"console=ttyS0 guestfs=%s:%d", VMCHANNEL_ADDR, VMCHANNEL_PORT);
add_cmdline (g, "-m");
- add_cmdline (g, "384"); /* XXX Choose best size. */
+ add_cmdline (g, "384"); /* XXX Choose best size. */
+ add_cmdline (g, "-no-kqemu"); /* Avoids a warning. */
add_cmdline (g, "-kernel");
add_cmdline (g, (char *) kernel);
add_cmdline (g, "-initrd");
close (rfd[0]);
dup (wfd[0]);
dup (rfd[1]);
+ close (wfd[0]);
+ close (rfd[1]);
#if 0
/* Set up a new process group, so we can signal this process
if ((r == -1 && errno == EINPROGRESS) || r == 0)
goto connected;
- perrorf (g, "connect");
+ if (errno != ENOENT)
+ perrorf (g, "connect");
tries--;
}
free (g->msg_out);
g->msg_out = NULL;
g->msg_out_size = 0;
+ g->msg_out_pos = 0;
g->stdout_watch =
main_loop.add_handle (g, g->fd[1],
g->sock_watch =
main_loop.add_handle (g, g->sock,
- GUESTFS_HANDLE_READABLE |
- GUESTFS_HANDLE_HANGUP |
- GUESTFS_HANDLE_ERROR,
+ GUESTFS_HANDLE_READABLE,
sock_read_event, g);
if (g->sock_watch == -1) {
error (g, "could not watch daemon communications socket");
if (g->verbose)
fprintf (stderr,
- "sock_event: %p g->state = %d, fd = %d, events = 0x%x\n",
+ "sock_read_event: %p g->state = %d, fd = %d, events = 0x%x\n",
g, g->state, fd, events);
if (g->sock != fd) {
goto cleanup;
}
- if (g->msg_in_size < len) return; /* Need more of this message. */
+ /* If this happens, it's pretty bad and we've probably lost synchronization.*/
+ if (len > GUESTFS_MESSAGE_MAX) {
+ error (g, "message length (%u) > maximum possible size (%d)",
+ len, GUESTFS_MESSAGE_MAX);
+ goto cleanup;
+ }
+
+ if (g->msg_in_size-4 < len) return; /* Need more of this message. */
/* This should not happen, and if it does it probably means we've
* lost all hope of synchronization.
*/
- if (g->msg_in_size > len) {
- error (g, "len = %d, but msg_in_size = %d", len, g->msg_in_size);
+ if (g->msg_in_size-4 > len) {
+ error (g, "len = %d, but msg_in_size-4 = %d", len, g->msg_in_size-4);
goto cleanup;
}
xdr_destroy (&xdr);
}
+/* The function is called whenever we can write something on the
+ * guestfsd (daemon inside the guest) communication socket.
+ */
+static void
+sock_write_event (void *data, int watch, int fd, int events)
+{
+ guestfs_h *g = (guestfs_h *) data;
+ int n;
+
+ if (g->verbose)
+ fprintf (stderr,
+ "sock_write_event: %p g->state = %d, fd = %d, events = 0x%x\n",
+ g, g->state, fd, events);
+
+ if (g->sock != fd) {
+ error (g, "sock_write_event: internal error: %d != %d", g->sock, fd);
+ return;
+ }
+
+ if (g->state != BUSY) {
+ error (g, "sock_write_event: state %d != BUSY", g->state);
+ return;
+ }
+
+ if (g->verbose)
+ fprintf (stderr, "sock_write_event: writing %d bytes ...\n",
+ g->msg_out_size - g->msg_out_pos);
+
+ n = write (g->sock, g->msg_out + g->msg_out_pos,
+ g->msg_out_size - g->msg_out_pos);
+ if (n == -1) {
+ if (errno != EAGAIN)
+ perrorf (g, "write");
+ return;
+ }
+
+ if (g->verbose)
+ fprintf (stderr, "sock_write_event: wrote %d bytes\n", n);
+
+ g->msg_out_pos += n;
+
+ /* More to write? */
+ if (g->msg_out_pos < g->msg_out_size)
+ return;
+
+ if (g->verbose)
+ fprintf (stderr, "sock_write_event: done writing, switching back to reading events\n");
+
+ free (g->msg_out);
+ g->msg_out_pos = g->msg_out_size = 0;
+
+ if (main_loop.remove_handle (g, g->sock_watch) == -1) {
+ error (g, "remove_handle failed in sock_write_event");
+ return;
+ }
+ g->sock_watch =
+ main_loop.add_handle (g, g->sock,
+ GUESTFS_HANDLE_READABLE,
+ sock_read_event, g);
+ if (g->sock_watch == -1) {
+ error (g, "add_handle failed in sock_write_event");
+ return;
+ }
+}
+
+/* Dispatch a call to the remote daemon. This function just queues
+ * the call in msg_out, to be sent when we next enter the main loop.
+ * Returns -1 for error, or the message serial number.
+ */
+static int
+dispatch (guestfs_h *g, int proc_nr, xdrproc_t xdrp, char *args)
+{
+ char buffer[GUESTFS_MESSAGE_MAX];
+ struct guestfs_message_header hdr;
+ XDR xdr;
+ unsigned len;
+ int serial = g->msg_next_serial++;
+
+ if (g->state != READY) {
+ error (g, "dispatch: state %d != READY", g->state);
+ return -1;
+ }
+
+ /* Serialize the header. */
+ hdr.prog = GUESTFS_PROGRAM;
+ hdr.vers = GUESTFS_PROTOCOL_VERSION;
+ hdr.proc = proc_nr;
+ hdr.direction = GUESTFS_DIRECTION_CALL;
+ hdr.serial = serial;
+ hdr.status = GUESTFS_STATUS_OK;
+
+ xdrmem_create (&xdr, buffer, sizeof buffer, XDR_ENCODE);
+ if (!xdr_guestfs_message_header (&xdr, &hdr)) {
+ error (g, "xdr_guestfs_message_header failed");
+ return -1;
+ }
+
+ /* Serialize the args. If any, because some message types
+ * have no parameters.
+ */
+ if (xdrp) {
+ if (!(*xdrp) (&xdr, args)) {
+ error (g, "dispatch failed to marshal args");
+ return -1;
+ }
+ }
+
+ len = xdr_getpos (&xdr);
+ xdr_destroy (&xdr);
+
+ /* Allocate the outgoing message buffer. */
+ g->msg_out = safe_malloc (g, len + 4);
+
+ g->msg_out_size = len + 4;
+ g->msg_out_pos = 0;
+ g->state = BUSY;
+
+ xdrmem_create (&xdr, g->msg_out, 4, XDR_ENCODE);
+ if (!xdr_uint32_t (&xdr, &len)) {
+ error (g, "xdr_uint32_t failed in dispatch");
+ goto cleanup1;
+ }
+
+ memcpy (g->msg_out + 4, buffer, len);
+
+ /* Change the handle to sock_write_event. */
+ if (main_loop.remove_handle (g, g->sock_watch) == -1) {
+ error (g, "remove_handle failed in dispatch");
+ goto cleanup1;
+ }
+ g->sock_watch =
+ main_loop.add_handle (g, g->sock,
+ GUESTFS_HANDLE_WRITABLE,
+ sock_write_event, g);
+ if (g->sock_watch == -1) {
+ error (g, "add_handle failed in dispatch");
+ goto cleanup1;
+ }
+
+ return serial;
+
+ cleanup1:
+ free (g->msg_out);
+ g->msg_out = NULL;
+ g->msg_out_size = 0;
+ g->state = READY;
+ return -1;
+}
+
+/* Check the return message from a call for validity. */
+static int
+check_reply_header (guestfs_h *g,
+ const struct guestfs_message_header *hdr,
+ int proc_nr, int serial)
+{
+ if (hdr->prog != GUESTFS_PROGRAM) {
+ error (g, "wrong program (%d/%d)", hdr->prog, GUESTFS_PROGRAM);
+ return -1;
+ }
+ if (hdr->vers != GUESTFS_PROTOCOL_VERSION) {
+ error (g, "wrong protocol version (%d/%d)",
+ hdr->vers, GUESTFS_PROTOCOL_VERSION);
+ return -1;
+ }
+ if (hdr->direction != GUESTFS_DIRECTION_REPLY) {
+ error (g, "unexpected message direction (%d/%d)",
+ hdr->direction, GUESTFS_DIRECTION_REPLY);
+ return -1;
+ }
+ if (hdr->proc != proc_nr) {
+ error (g, "unexpected procedure number (%d/%d)", hdr->proc, proc_nr);
+ return -1;
+ }
+ if (hdr->serial != serial) {
+ error (g, "unexpected serial (%d/%d)", hdr->serial, serial);
+ return -1;
+ }
+
+ return 0;
+}
+
+/* The high-level actions are autogenerated by generator.ml. Include
+ * them here.
+ */
+#include "guestfs-actions.c"
+
/* This is the default main loop implementation, using select(2). */
struct handle_cb_data {
git.annexia.org / libguestfs.git / blobdiff