1 /* libguestfs - the guestfsd daemon
2 * Copyright (C) 2009 Red Hat Inc.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28 #include <sys/param.h> /* defines MIN */
29 #include <rpc/types.h>
33 #include "../src/guestfs_protocol.h"
35 /* The message currently being processed. */
39 /* The daemon communications socket. */
49 struct guestfs_message_header hdr;
50 struct timeval start_t, end_t;
51 int64_t start_us, end_us, elapsed_us;
57 /* Most common errors are leaked memory and leaked file descriptors,
58 * so run this between each command:
61 system ("ls -l /proc/self/fd");
64 /* Read the length word. */
65 xread (sock, lenbuf, 4);
66 xdrmem_create (&xdr, lenbuf, 4, XDR_DECODE);
67 xdr_uint32_t (&xdr, &len);
70 if (len > GUESTFS_MESSAGE_MAX) {
71 fprintf (stderr, "guestfsd: incoming message is too long (%u bytes)\n",
78 reply_with_perror ("malloc");
82 xread (sock, buf, len);
88 for (i = 0; i < len; i += 16) {
90 for (j = i; j < MIN (i+16, len); ++j)
91 printf ("%02x ", (unsigned char) buf[j]);
95 for (j = i; j < MIN (i+16, len); ++j)
97 printf ("%c", buf[j]);
100 for (; j < i+16; ++j)
107 /* In verbose mode, display the time taken to run each command. */
109 gettimeofday (&start_t, NULL);
111 /* Decode the message header. */
112 xdrmem_create (&xdr, buf, len, XDR_DECODE);
113 if (!xdr_guestfs_message_header (&xdr, &hdr)) {
114 fprintf (stderr, "guestfsd: could not decode message header\n");
118 /* Check the version etc. */
119 if (hdr.prog != GUESTFS_PROGRAM) {
120 reply_with_error ("wrong program (%d)", hdr.prog);
123 if (hdr.vers != GUESTFS_PROTOCOL_VERSION) {
124 reply_with_error ("wrong protocol version (%d)", hdr.vers);
127 if (hdr.direction != GUESTFS_DIRECTION_CALL) {
128 reply_with_error ("unexpected message direction (%d)", hdr.direction);
131 if (hdr.status != GUESTFS_STATUS_OK) {
132 reply_with_error ("unexpected message status (%d)", hdr.status);
136 /* Now start to process this message. */
139 dispatch_incoming_message (&xdr);
140 /* Note that dispatch_incoming_message will also send a reply. */
142 /* In verbose mode, display the time taken to run each command. */
144 gettimeofday (&end_t, NULL);
146 start_us = (int64_t) start_t.tv_sec * 1000000 + start_t.tv_usec;
147 end_us = (int64_t) end_t.tv_sec * 1000000 + end_t.tv_usec;
148 elapsed_us = end_us - start_us;
149 fprintf (stderr, "proc %d serial %d took %d.%02d seconds\n",
151 (int) (elapsed_us / 1000000),
152 (int) ((elapsed_us / 10000) % 100));
161 static void send_error (const char *msg);
164 reply_with_error (const char *fs, ...)
166 char err[GUESTFS_ERROR_LEN];
170 vsnprintf (err, sizeof err, fs, args);
177 reply_with_perror (const char *fs, ...)
179 char buf1[GUESTFS_ERROR_LEN];
180 char buf2[GUESTFS_ERROR_LEN];
185 vsnprintf (buf1, sizeof buf1, fs, args);
188 snprintf (buf2, sizeof buf2, "%s: %s", buf1, strerror (err));
194 send_error (const char *msg)
197 char buf[GUESTFS_ERROR_LEN + 200];
199 struct guestfs_message_header hdr;
200 struct guestfs_message_error err;
203 fprintf (stderr, "guestfsd: error: %s\n", msg);
205 xdrmem_create (&xdr, buf, sizeof buf, XDR_ENCODE);
207 hdr.prog = GUESTFS_PROGRAM;
208 hdr.vers = GUESTFS_PROTOCOL_VERSION;
209 hdr.direction = GUESTFS_DIRECTION_REPLY;
210 hdr.status = GUESTFS_STATUS_ERROR;
214 if (!xdr_guestfs_message_header (&xdr, &hdr)) {
215 fprintf (stderr, "guestfsd: failed to encode error message header\n");
219 err.error_message = (char *) msg;
221 if (!xdr_guestfs_message_error (&xdr, &err)) {
222 fprintf (stderr, "guestfsd: failed to encode error message body\n");
226 len = xdr_getpos (&xdr);
229 xdrmem_create (&xdr, lenbuf, 4, XDR_ENCODE);
230 xdr_uint32_t (&xdr, &len);
233 if (xwrite (sock, lenbuf, 4) == -1) {
234 fprintf (stderr, "xwrite failed\n");
237 if (xwrite (sock, buf, len) == -1) {
238 fprintf (stderr, "xwrite failed\n");
244 reply (xdrproc_t xdrp, char *ret)
247 char buf[GUESTFS_MESSAGE_MAX];
249 struct guestfs_message_header hdr;
252 xdrmem_create (&xdr, buf, sizeof buf, XDR_ENCODE);
254 hdr.prog = GUESTFS_PROGRAM;
255 hdr.vers = GUESTFS_PROTOCOL_VERSION;
256 hdr.direction = GUESTFS_DIRECTION_REPLY;
257 hdr.status = GUESTFS_STATUS_OK;
261 if (!xdr_guestfs_message_header (&xdr, &hdr)) {
262 fprintf (stderr, "guestfsd: failed to encode reply header\n");
267 if (!(*xdrp) (&xdr, ret)) {
268 fprintf (stderr, "guestfsd: failed to encode reply body\n");
273 len = xdr_getpos (&xdr);
276 xdrmem_create (&xdr, lenbuf, 4, XDR_ENCODE);
277 xdr_uint32_t (&xdr, &len);
280 if (xwrite (sock, lenbuf, 4) == -1) {
281 fprintf (stderr, "xwrite failed\n");
284 if (xwrite (sock, buf, len) == len) {
285 fprintf (stderr, "xwrite failed\n");
290 /* Receive file chunks, repeatedly calling 'cb'. */
292 receive_file (receive_cb cb, void *opaque)
302 /* Read the length word. */
303 xread (sock, lenbuf, 4);
304 xdrmem_create (&xdr, lenbuf, 4, XDR_DECODE);
305 xdr_uint32_t (&xdr, &len);
308 if (len == GUESTFS_CANCEL_FLAG)
309 continue; /* Just ignore it. */
311 if (len > GUESTFS_MESSAGE_MAX) {
312 fprintf (stderr, "guestfsd: incoming message is too long (%u bytes)\n",
323 xread (sock, buf, len);
325 xdrmem_create (&xdr, buf, len, XDR_DECODE);
326 memset (&chunk, 0, sizeof chunk);
327 if (!xdr_guestfs_chunk (&xdr, &chunk)) {
336 printf ("receive_file: got chunk: cancel = %d, len = %d, buf = %p\n",
337 chunk.cancel, chunk.data.data_len, chunk.data.data_val);
340 fprintf (stderr, "receive_file: received cancellation from library\n");
341 xdr_free ((xdrproc_t) xdr_guestfs_chunk, (char *) &chunk);
344 if (chunk.data.data_len == 0) {
345 xdr_free ((xdrproc_t) xdr_guestfs_chunk, (char *) &chunk);
346 return 0; /* end of file */
350 r = cb (opaque, chunk.data.data_val, chunk.data.data_len);
354 xdr_free ((xdrproc_t) xdr_guestfs_chunk, (char *) &chunk);
355 if (r == -1) /* write error */
360 /* Send a cancellation flag back to the library. */
362 cancel_receive (void)
366 uint32_t flag = GUESTFS_CANCEL_FLAG;
368 xdrmem_create (&xdr, fbuf, sizeof fbuf, XDR_ENCODE);
369 xdr_uint32_t (&xdr, &flag);
372 if (xwrite (sock, fbuf, sizeof fbuf) == -1) {
373 perror ("write to socket");
377 /* Keep receiving chunks and discarding, until library sees cancel. */
378 (void) receive_file (NULL, NULL);
381 static int check_for_library_cancellation (void);
382 static int send_chunk (const guestfs_chunk *);
384 /* Also check if the library sends us a cancellation message. */
386 send_file_write (const void *buf, int len)
391 if (len > GUESTFS_MAX_CHUNK_SIZE) {
392 fprintf (stderr, "send_file_write: len (%d) > GUESTFS_MAX_CHUNK_SIZE (%d)\n",
393 len, GUESTFS_MAX_CHUNK_SIZE);
397 cancel = check_for_library_cancellation ();
401 chunk.data.data_len = 0;
402 chunk.data.data_val = NULL;
405 chunk.data.data_len = len;
406 chunk.data.data_val = (char *) buf;
409 if (send_chunk (&chunk) == -1)
412 if (cancel) return -2;
417 check_for_library_cancellation (void)
427 FD_SET (sock, &rset);
430 r = select (sock+1, &rset, NULL, NULL, &tv);
438 /* Read the message from the daemon. */
439 r = xread (sock, buf, sizeof buf);
445 xdrmem_create (&xdr, buf, sizeof buf, XDR_DECODE);
446 xdr_uint32_t (&xdr, &flag);
449 if (flag != GUESTFS_CANCEL_FLAG) {
450 fprintf (stderr, "check_for_library_cancellation: read 0x%x from library, expected 0x%x\n",
451 flag, GUESTFS_CANCEL_FLAG);
459 send_file_end (int cancel)
463 chunk.cancel = cancel;
464 chunk.data.data_len = 0;
465 chunk.data.data_val = NULL;
470 send_chunk (const guestfs_chunk *chunk)
472 char buf[GUESTFS_MAX_CHUNK_SIZE + 48];
477 xdrmem_create (&xdr, buf, sizeof buf, XDR_ENCODE);
478 if (!xdr_guestfs_chunk (&xdr, (guestfs_chunk *) chunk)) {
479 fprintf (stderr, "send_chunk: failed to encode chunk\n");
484 len = xdr_getpos (&xdr);
487 xdrmem_create (&xdr, lenbuf, 4, XDR_ENCODE);
488 xdr_uint32_t (&xdr, &len);
491 (void) xwrite (sock, lenbuf, 4);
492 (void) xwrite (sock, buf, len);