--- /dev/null
+/* libguestfs
+ * Copyright (C) 2009-2010 Red Hat Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <config.h>
+
+#define _BSD_SOURCE /* for mkdtemp, usleep */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <time.h>
+#include <sys/stat.h>
+#include <sys/select.h>
+#include <dirent.h>
+#include <signal.h>
+
+#include <rpc/types.h>
+#include <rpc/xdr.h>
+
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#ifdef HAVE_SYS_WAIT_H
+#include <sys/wait.h>
+#endif
+
+#ifdef HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+
+#ifdef HAVE_SYS_UN_H
+#include <sys/un.h>
+#endif
+
+#include <arpa/inet.h>
+#include <netinet/in.h>
+
+#include "c-ctype.h"
+#include "glthread/lock.h"
+#include "ignore-value.h"
+
+#include "guestfs.h"
+#include "guestfs-internal.h"
+#include "guestfs-internal-actions.h"
+#include "guestfs_protocol.h"
+
+/* 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
+ * are five different cases to consider:
+ *
+ * (1) A non-daemon function. There is no RPC involved at all, it's
+ * all handled inside the library.
+ *
+ * (2) A simple RPC (eg. "mount"). We write the request, then read
+ * the reply. The sequence of calls is:
+ *
+ * guestfs___set_busy
+ * guestfs___send
+ * guestfs___recv
+ * guestfs___end_busy
+ *
+ * (3) An RPC with FileOut parameters (eg. "upload"). We write the
+ * request, then write the file(s), then read the reply. The sequence
+ * of calls is:
+ *
+ * guestfs___set_busy
+ * guestfs___send
+ * guestfs___send_file (possibly multiple times)
+ * guestfs___recv
+ * guestfs___end_busy
+ *
+ * (4) An RPC with FileIn parameters (eg. "download"). We write the
+ * request, then read the reply, then read the file(s). The sequence
+ * of calls is:
+ *
+ * guestfs___set_busy
+ * guestfs___send
+ * guestfs___recv
+ * guestfs___recv_file (possibly multiple times)
+ * guestfs___end_busy
+ *
+ * (5) Both FileOut and FileIn parameters. There are no calls like
+ * this in the current API, but they would be implemented as a
+ * combination of cases (3) and (4).
+ *
+ * During all writes and reads, we also select(2) on qemu stdout
+ * looking for messages (guestfsd stderr and guest kernel dmesg), and
+ * anything received is passed up through the log_message_cb. This is
+ * also the reason why all the sockets are non-blocking. We also have
+ * to check for EOF (qemu died). All of this is handled by the
+ * functions send_to_daemon and recv_from_daemon.
+ */
+
+static int
+xwrite (int fd, const void *v_buf, size_t len)
+{
+ const char *buf = v_buf;
+ int r;
+
+ while (len > 0) {
+ r = write (fd, buf, len);
+ if (r == -1)
+ return -1;
+
+ buf += r;
+ len -= r;
+ }
+
+ return 0;
+}
+
+int
+guestfs___set_busy (guestfs_h *g)
+{
+ if (g->state != READY) {
+ error (g, _("guestfs_set_busy: called when in state %d != READY"),
+ g->state);
+ return -1;
+ }
+ g->state = BUSY;
+ return 0;
+}
+
+int
+guestfs___end_busy (guestfs_h *g)
+{
+ switch (g->state)
+ {
+ case BUSY:
+ g->state = READY;
+ break;
+ case CONFIG:
+ case READY:
+ break;
+
+ case LAUNCHING:
+ case NO_HANDLE:
+ default:
+ error (g, _("guestfs_end_busy: called when in state %d"), g->state);
+ return -1;
+ }
+ return 0;
+}
+
+/* This is called if we detect EOF, ie. qemu died. */
+static void
+child_cleanup (guestfs_h *g)
+{
+ if (g->verbose)
+ fprintf (stderr, "child_cleanup: %p: child process died\n", g);
+
+ /*if (g->pid > 0) kill (g->pid, SIGTERM);*/
+ if (g->recoverypid > 0) kill (g->recoverypid, 9);
+ waitpid (g->pid, NULL, 0);
+ if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
+ close (g->fd[0]);
+ close (g->fd[1]);
+ close (g->sock);
+ g->fd[0] = -1;
+ g->fd[1] = -1;
+ g->sock = -1;
+ g->pid = 0;
+ g->recoverypid = 0;
+ memset (&g->launch_t, 0, sizeof g->launch_t);
+ g->state = CONFIG;
+ if (g->subprocess_quit_cb)
+ g->subprocess_quit_cb (g, g->subprocess_quit_cb_data);
+}
+
+static int
+read_log_message_or_eof (guestfs_h *g, int fd, int error_if_eof)
+{
+ char buf[BUFSIZ];
+ int n;
+
+#if 0
+ if (g->verbose)
+ fprintf (stderr,
+ "read_log_message_or_eof: %p g->state = %d, fd = %d\n",
+ g, g->state, fd);
+#endif
+
+ /* QEMU's console emulates a 16550A serial port. The real 16550A
+ * device has a small FIFO buffer (16 bytes) which means here we see
+ * lots of small reads of 1-16 bytes in length, usually single
+ * bytes.
+ */
+ n = read (fd, buf, sizeof buf);
+ if (n == 0) {
+ /* Hopefully this indicates the qemu child process has died. */
+ child_cleanup (g);
+
+ if (error_if_eof) {
+ /* We weren't expecting eof here (called from launch) so place
+ * something in the error buffer. RHBZ#588851.
+ */
+ error (g, "child process died unexpectedly");
+ }
+ return -1;
+ }
+
+ if (n == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ return 0;
+
+ perrorf (g, "read");
+ return -1;
+ }
+
+ /* In verbose mode, copy all log messages to stderr. */
+ if (g->verbose)
+ ignore_value (write (STDERR_FILENO, buf, n));
+
+ /* It's an actual log message, send it upwards if anyone is listening. */
+ if (g->log_message_cb)
+ g->log_message_cb (g, g->log_message_cb_data, buf, n);
+
+ return 0;
+}
+
+static int
+check_for_daemon_cancellation_or_eof (guestfs_h *g, int fd)
+{
+ char buf[4];
+ int n;
+ uint32_t flag;
+ XDR xdr;
+
+ if (g->verbose)
+ fprintf (stderr,
+ "check_for_daemon_cancellation_or_eof: %p g->state = %d, fd = %d\n",
+ g, g->state, fd);
+
+ n = read (fd, buf, 4);
+ 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);
+
+ 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);
+ return -1;
+ }
+
+ return -2;
+}
+
+/* This writes the whole N bytes of BUF to the daemon socket.
+ *
+ * If the whole write is successful, it returns 0.
+ * If there was an error, it returns -1.
+ * If the daemon sent a cancellation message, it returns -2.
+ *
+ * It also checks qemu stdout for log messages and passes those up
+ * through log_message_cb.
+ *
+ * It also checks for EOF (qemu died) and passes that up through the
+ * child_cleanup function above.
+ */
+int
+guestfs__send_to_daemon (guestfs_h *g, const void *v_buf, size_t n)
+{
+ const char *buf = v_buf;
+ fd_set rset, rset2;
+ fd_set wset, wset2;
+
+ if (g->verbose)
+ fprintf (stderr,
+ "send_to_daemon: %p g->state = %d, n = %zu\n", g, g->state, n);
+
+ FD_ZERO (&rset);
+ FD_ZERO (&wset);
+
+ FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
+ FD_SET (g->sock, &rset); /* Read socket for cancellation & EOF. */
+ FD_SET (g->sock, &wset); /* Write to socket to send the data. */
+
+ int max_fd = MAX (g->sock, g->fd[1]);
+
+ while (n > 0) {
+ rset2 = rset;
+ wset2 = wset;
+ int r = select (max_fd+1, &rset2, &wset2, NULL, NULL);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "select");
+ return -1;
+ }
+
+ if (FD_ISSET (g->fd[1], &rset2)) {
+ if (read_log_message_or_eof (g, g->fd[1], 0) == -1)
+ return -1;
+ }
+ if (FD_ISSET (g->sock, &rset2)) {
+ r = check_for_daemon_cancellation_or_eof (g, g->sock);
+ if (r < 0)
+ return r;
+ }
+ if (FD_ISSET (g->sock, &wset2)) {
+ r = write (g->sock, buf, n);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "write");
+ if (errno == EPIPE) /* Disconnected from guest (RHBZ#508713). */
+ child_cleanup (g);
+ return -1;
+ }
+ buf += r;
+ n -= r;
+ }
+ }
+
+ return 0;
+}
+
+/* This reads a single message, file chunk, launch flag or
+ * cancellation flag from the daemon. If something was read, it
+ * returns 0, otherwise -1.
+ *
+ * Both size_rtn and buf_rtn must be passed by the caller as non-NULL.
+ *
+ * *size_rtn returns the size of the returned message or it may be
+ * GUESTFS_LAUNCH_FLAG or GUESTFS_CANCEL_FLAG.
+ *
+ * *buf_rtn is returned containing the message (if any) or will be set
+ * to NULL. *buf_rtn must be freed by the caller.
+ *
+ * It also checks qemu stdout for log messages and passes those up
+ * through log_message_cb.
+ *
+ * It also checks for EOF (qemu died) and passes that up through the
+ * child_cleanup function above.
+ */
+int
+guestfs__recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn)
+{
+ fd_set rset, rset2;
+
+ if (g->verbose)
+ fprintf (stderr,
+ "recv_from_daemon: %p g->state = %d, size_rtn = %p, buf_rtn = %p\n",
+ g, g->state, size_rtn, buf_rtn);
+
+ FD_ZERO (&rset);
+
+ FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
+ FD_SET (g->sock, &rset); /* Read socket for data & EOF. */
+
+ int max_fd = MAX (g->sock, g->fd[1]);
+
+ *size_rtn = 0;
+ *buf_rtn = NULL;
+
+ char lenbuf[4];
+ /* nr is the size of the message, but we prime it as -4 because we
+ * have to read the message length word first.
+ */
+ ssize_t nr = -4;
+
+ while (nr < (ssize_t) *size_rtn) {
+ rset2 = rset;
+ int r = select (max_fd+1, &rset2, NULL, NULL, NULL);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "select");
+ free (*buf_rtn);
+ *buf_rtn = NULL;
+ return -1;
+ }
+
+ if (FD_ISSET (g->fd[1], &rset2)) {
+ if (read_log_message_or_eof (g, g->fd[1], 0) == -1) {
+ free (*buf_rtn);
+ *buf_rtn = NULL;
+ return -1;
+ }
+ }
+ if (FD_ISSET (g->sock, &rset2)) {
+ if (nr < 0) { /* Have we read the message length word yet? */
+ r = read (g->sock, lenbuf+nr+4, -nr);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ int err = errno;
+ perrorf (g, "read");
+ /* Under some circumstances we see "Connection reset by peer"
+ * here when the child dies suddenly. Catch this and call
+ * the cleanup function, same as for EOF.
+ */
+ if (err == ECONNRESET)
+ child_cleanup (g);
+ return -1;
+ }
+ if (r == 0) {
+ error (g, _("unexpected end of file when reading from daemon"));
+ child_cleanup (g);
+ return -1;
+ }
+ nr += r;
+
+ if (nr < 0) /* Still not got the whole length word. */
+ continue;
+
+ XDR xdr;
+ xdrmem_create (&xdr, lenbuf, 4, XDR_DECODE);
+ xdr_uint32_t (&xdr, size_rtn);
+ xdr_destroy (&xdr);
+
+ if (*size_rtn == GUESTFS_LAUNCH_FLAG) {
+ if (g->state != LAUNCHING)
+ error (g, _("received magic signature from guestfsd, but in state %d"),
+ g->state);
+ else {
+ g->state = READY;
+ if (g->launch_done_cb)
+ g->launch_done_cb (g, g->launch_done_cb_data);
+ }
+ return 0;
+ }
+ else if (*size_rtn == GUESTFS_CANCEL_FLAG)
+ return 0;
+ /* If this happens, it's pretty bad and we've probably lost
+ * synchronization.
+ */
+ else if (*size_rtn > GUESTFS_MESSAGE_MAX) {
+ error (g, _("message length (%u) > maximum possible size (%d)"),
+ (unsigned) *size_rtn, GUESTFS_MESSAGE_MAX);
+ return -1;
+ }
+
+ /* Allocate the complete buffer, size now known. */
+ *buf_rtn = safe_malloc (g, *size_rtn);
+ /*FALLTHROUGH*/
+ }
+
+ size_t sizetoread = *size_rtn - nr;
+ if (sizetoread > BUFSIZ) sizetoread = BUFSIZ;
+
+ r = read (g->sock, (char *) (*buf_rtn) + nr, sizetoread);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "read");
+ free (*buf_rtn);
+ *buf_rtn = NULL;
+ return -1;
+ }
+ if (r == 0) {
+ error (g, _("unexpected end of file when reading from daemon"));
+ child_cleanup (g);
+ free (*buf_rtn);
+ *buf_rtn = NULL;
+ return -1;
+ }
+ nr += r;
+ }
+ }
+
+ /* Got the full message, caller can start processing it. */
+#ifdef ENABLE_PACKET_DUMP
+ if (g->verbose) {
+ ssize_t i, j;
+
+ for (i = 0; i < nr; i += 16) {
+ printf ("%04zx: ", i);
+ for (j = i; j < MIN (i+16, nr); ++j)
+ printf ("%02x ", (*(unsigned char **)buf_rtn)[j]);
+ for (; j < i+16; ++j)
+ printf (" ");
+ printf ("|");
+ for (j = i; j < MIN (i+16, nr); ++j)
+ if (c_isprint ((*(char **)buf_rtn)[j]))
+ printf ("%c", (*(char **)buf_rtn)[j]);
+ else
+ printf (".");
+ for (; j < i+16; ++j)
+ printf (" ");
+ printf ("|\n");
+ }
+ }
+#endif
+
+ return 0;
+}
+
+/* This is very much like recv_from_daemon above, but g->sock is
+ * a listening socket and we are accepting a new connection on
+ * that socket instead of reading anything. Returns the newly
+ * accepted socket.
+ */
+int
+guestfs__accept_from_daemon (guestfs_h *g)
+{
+ fd_set rset, rset2;
+
+ if (g->verbose)
+ fprintf (stderr,
+ "accept_from_daemon: %p g->state = %d\n", g, g->state);
+
+ FD_ZERO (&rset);
+
+ FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
+ FD_SET (g->sock, &rset); /* Read socket for accept. */
+
+ int max_fd = MAX (g->sock, g->fd[1]);
+ int sock = -1;
+
+ while (sock == -1) {
+ /* If the qemu process has died, clean up the zombie (RHBZ#579155).
+ * By partially polling in the select below we ensure that this
+ * function will be called eventually.
+ */
+ waitpid (g->pid, NULL, WNOHANG);
+
+ rset2 = rset;
+
+ struct timeval tv = { .tv_sec = 1, .tv_usec = 0 };
+ int r = select (max_fd+1, &rset2, NULL, NULL, &tv);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "select");
+ return -1;
+ }
+
+ if (FD_ISSET (g->fd[1], &rset2)) {
+ if (read_log_message_or_eof (g, g->fd[1], 1) == -1)
+ return -1;
+ }
+ if (FD_ISSET (g->sock, &rset2)) {
+ sock = accept (g->sock, NULL, NULL);
+ if (sock == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "accept");
+ return -1;
+ }
+ }
+ }
+
+ return sock;
+}
+
+int
+guestfs___send (guestfs_h *g, int proc_nr, xdrproc_t xdrp, char *args)
+{
+ struct guestfs_message_header hdr;
+ XDR xdr;
+ u_int32_t len;
+ int serial = g->msg_next_serial++;
+ int r;
+ char *msg_out;
+ size_t msg_out_size;
+
+ if (g->state != BUSY) {
+ error (g, _("guestfs___send: state %d != BUSY"), g->state);
+ return -1;
+ }
+
+ /* We have to allocate this message buffer on the heap because
+ * it is quite large (although will be mostly unused). We
+ * can't allocate it on the stack because in some environments
+ * we have quite limited stack space available, notably when
+ * running in the JVM.
+ */
+ msg_out = safe_malloc (g, GUESTFS_MESSAGE_MAX + 4);
+ xdrmem_create (&xdr, msg_out + 4, GUESTFS_MESSAGE_MAX, XDR_ENCODE);
+
+ /* 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;
+
+ if (!xdr_guestfs_message_header (&xdr, &hdr)) {
+ error (g, _("xdr_guestfs_message_header failed"));
+ goto cleanup1;
+ }
+
+ /* 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"));
+ goto cleanup1;
+ }
+ }
+
+ /* Get the actual length of the message, resize the buffer to match
+ * the actual length, and write the length word at the beginning.
+ */
+ len = xdr_getpos (&xdr);
+ xdr_destroy (&xdr);
+
+ msg_out = safe_realloc (g, msg_out, len + 4);
+ msg_out_size = len + 4;
+
+ xdrmem_create (&xdr, msg_out, 4, XDR_ENCODE);
+ xdr_uint32_t (&xdr, &len);
+
+ again:
+ r = guestfs__send_to_daemon (g, msg_out, msg_out_size);
+ if (r == -2) /* Ignore stray daemon cancellations. */
+ goto again;
+ if (r == -1)
+ goto cleanup1;
+ free (msg_out);
+
+ return serial;
+
+ cleanup1:
+ free (msg_out);
+ return -1;
+}
+
+static int cancel = 0; /* XXX Implement file cancellation. */
+static int send_file_chunk (guestfs_h *g, int cancel, const char *buf, size_t len);
+static int send_file_data (guestfs_h *g, const char *buf, size_t len);
+static int send_file_cancellation (guestfs_h *g);
+static int send_file_complete (guestfs_h *g);
+
+/* Send a file.
+ * Returns:
+ * 0 OK
+ * -1 error
+ * -2 daemon cancelled (we must read the error message)
+ */
+int
+guestfs___send_file (guestfs_h *g, const char *filename)
+{
+ char buf[GUESTFS_MAX_CHUNK_SIZE];
+ int fd, r, err;
+
+ fd = open (filename, O_RDONLY);
+ 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;
+ }
+
+ /* Send file in chunked encoding. */
+ while (!cancel) {
+ r = read (fd, buf, sizeof buf);
+ if (r == -1 && (errno == EINTR || errno == EAGAIN))
+ continue;
+ if (r <= 0) break;
+ err = send_file_data (g, buf, r);
+ if (err < 0) {
+ if (err == -2) /* daemon sent cancellation */
+ send_file_cancellation (g);
+ return err;
+ }
+ }
+
+ if (cancel) { /* cancel from either end */
+ send_file_cancellation (g);
+ return -1;
+ }
+
+ if (r == -1) {
+ perrorf (g, "read: %s", filename);
+ send_file_cancellation (g);
+ return -1;
+ }
+
+ /* End of file, but before we send that, we need to close
+ * the file and check for errors.
+ */
+ if (close (fd) == -1) {
+ perrorf (g, "close: %s", filename);
+ send_file_cancellation (g);
+ return -1;
+ }
+
+ return send_file_complete (g);
+}
+
+/* Send a chunk of file data. */
+static int
+send_file_data (guestfs_h *g, const char *buf, size_t len)
+{
+ return send_file_chunk (g, 0, buf, len);
+}
+
+/* Send a cancellation message. */
+static int
+send_file_cancellation (guestfs_h *g)
+{
+ return send_file_chunk (g, 1, NULL, 0);
+}
+
+/* Send a file complete chunk. */
+static int
+send_file_complete (guestfs_h *g)
+{
+ char buf[1];
+ return send_file_chunk (g, 0, buf, 0);
+}
+
+static int
+send_file_chunk (guestfs_h *g, int cancel, const char *buf, size_t buflen)
+{
+ u_int32_t len;
+ int r;
+ guestfs_chunk chunk;
+ XDR xdr;
+ char *msg_out;
+ size_t msg_out_size;
+
+ if (g->state != BUSY) {
+ error (g, _("send_file_chunk: state %d != READY"), g->state);
+ return -1;
+ }
+
+ /* Allocate the chunk buffer. Don't use the stack to avoid
+ * excessive stack usage and unnecessary copies.
+ */
+ msg_out = safe_malloc (g, GUESTFS_MAX_CHUNK_SIZE + 4 + 48);
+ xdrmem_create (&xdr, msg_out + 4, GUESTFS_MAX_CHUNK_SIZE + 48, XDR_ENCODE);
+
+ /* Serialize the chunk. */
+ chunk.cancel = cancel;
+ chunk.data.data_len = buflen;
+ chunk.data.data_val = (char *) buf;
+
+ if (!xdr_guestfs_chunk (&xdr, &chunk)) {
+ error (g, _("xdr_guestfs_chunk failed (buf = %p, buflen = %zu)"),
+ buf, buflen);
+ xdr_destroy (&xdr);
+ goto cleanup1;
+ }
+
+ len = xdr_getpos (&xdr);
+ xdr_destroy (&xdr);
+
+ /* Reduce the size of the outgoing message buffer to the real length. */
+ msg_out = safe_realloc (g, msg_out, len + 4);
+ msg_out_size = len + 4;
+
+ xdrmem_create (&xdr, msg_out, 4, XDR_ENCODE);
+ xdr_uint32_t (&xdr, &len);
+
+ r = guestfs__send_to_daemon (g, msg_out, msg_out_size);
+
+ /* Did the daemon send a cancellation message? */
+ if (r == -2) {
+ if (g->verbose)
+ fprintf (stderr, "got daemon cancellation\n");
+ return -2;
+ }
+
+ if (r == -1)
+ goto cleanup1;
+
+ free (msg_out);
+
+ return 0;
+
+ cleanup1:
+ free (msg_out);
+ return -1;
+}
+
+/* Receive a reply. */
+int
+guestfs___recv (guestfs_h *g, const char *fn,
+ guestfs_message_header *hdr,
+ guestfs_message_error *err,
+ xdrproc_t xdrp, char *ret)
+{
+ XDR xdr;
+ 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;
+ }
+
+ xdrmem_create (&xdr, buf, size, XDR_DECODE);
+
+ if (!xdr_guestfs_message_header (&xdr, hdr)) {
+ error (g, "%s: failed to parse reply header", fn);
+ xdr_destroy (&xdr);
+ free (buf);
+ return -1;
+ }
+ if (hdr->status == GUESTFS_STATUS_ERROR) {
+ if (!xdr_guestfs_message_error (&xdr, err)) {
+ error (g, "%s: failed to parse reply error", fn);
+ xdr_destroy (&xdr);
+ free (buf);
+ return -1;
+ }
+ } else {
+ if (xdrp && ret && !xdrp (&xdr, ret)) {
+ error (g, "%s: failed to parse reply", fn);
+ xdr_destroy (&xdr);
+ free (buf);
+ return -1;
+ }
+ }
+ xdr_destroy (&xdr);
+ free (buf);
+
+ return 0;
+}
+
+/* Receive a file. */
+
+/* Returns -1 = error, 0 = EOF, > 0 = more data */
+static ssize_t receive_file_data (guestfs_h *g, void **buf);
+
+int
+guestfs___recv_file (guestfs_h *g, const char *filename)
+{
+ void *buf;
+ int fd, r;
+
+ fd = open (filename, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY, 0666);
+ if (fd == -1) {
+ perrorf (g, "open: %s", filename);
+ goto cancel;
+ }
+
+ /* Receive the file in chunked encoding. */
+ while ((r = receive_file_data (g, &buf)) > 0) {
+ if (xwrite (fd, buf, r) == -1) {
+ perrorf (g, "%s: write", filename);
+ free (buf);
+ goto cancel;
+ }
+ free (buf);
+ }
+
+ if (r == -1) {
+ error (g, _("%s: error in chunked encoding"), filename);
+ return -1;
+ }
+
+ if (close (fd) == -1) {
+ perrorf (g, "close: %s", filename);
+ return -1;
+ }
+
+ return 0;
+
+ cancel: ;
+ /* Send cancellation message to daemon, then wait until it
+ * cancels (just throwing away data).
+ */
+ XDR xdr;
+ char fbuf[4];
+ uint32_t flag = GUESTFS_CANCEL_FLAG;
+
+ if (g->verbose)
+ fprintf (stderr, "%s: waiting for daemon to acknowledge cancellation\n",
+ __func__);
+
+ xdrmem_create (&xdr, fbuf, sizeof fbuf, XDR_ENCODE);
+ xdr_uint32_t (&xdr, &flag);
+ xdr_destroy (&xdr);
+
+ if (xwrite (g->sock, fbuf, sizeof fbuf) == -1) {
+ perrorf (g, _("write to daemon socket"));
+ return -1;
+ }
+
+ while (receive_file_data (g, NULL) > 0)
+ ; /* just discard it */
+
+ return -1;
+}
+
+/* Receive a chunk of file data. */
+/* Returns -1 = error, 0 = EOF, > 0 = more data */
+static ssize_t
+receive_file_data (guestfs_h *g, void **buf_r)
+{
+ int r;
+ void *buf;
+ uint32_t len;
+ XDR xdr;
+ guestfs_chunk chunk;
+
+ r = guestfs__recv_from_daemon (g, &len, &buf);
+ if (r == -1) {
+ error (g, _("receive_file_data: parse error in reply callback"));
+ return -1;
+ }
+
+ if (len == GUESTFS_LAUNCH_FLAG || len == GUESTFS_CANCEL_FLAG) {
+ error (g, _("receive_file_data: unexpected flag received when reading file chunks"));
+ return -1;
+ }
+
+ memset (&chunk, 0, sizeof chunk);
+
+ xdrmem_create (&xdr, buf, len, XDR_DECODE);
+ if (!xdr_guestfs_chunk (&xdr, &chunk)) {
+ error (g, _("failed to parse file chunk"));
+ free (buf);
+ return -1;
+ }
+ xdr_destroy (&xdr);
+ /* After decoding, the original buffer is no longer used. */
+ free (buf);
+
+ if (chunk.cancel) {
+ error (g, _("file receive cancelled by daemon"));
+ free (chunk.data.data_val);
+ return -1;
+ }
+
+ if (chunk.data.data_len == 0) { /* end of transfer */
+ free (chunk.data.data_val);
+ return 0;
+ }
+
+ if (buf_r) *buf_r = chunk.data.data_val;
+ else free (chunk.data.data_val); /* else caller frees */
+
+ return chunk.data.data_len;
+}
git.annexia.org / libguestfs.git / blobdiff