2 * Socket and pipe I/O utilities used in rsync.
4 * Copyright (C) 1996-2001 Andrew Tridgell
5 * Copyright (C) 1996 Paul Mackerras
6 * Copyright (C) 2001, 2002 Martin Pool <mbp@samba.org>
7 * Copyright (C) 2003-2008 Wayne Davison
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 3 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, visit the http://fsf.org website.
23 /* Rsync provides its own multiplexing system, which is used to send
24 * stderr and stdout over a single socket.
26 * For historical reasons this is off during the start of the
27 * connection, but it's switched on quite early using
28 * io_start_multiplex_out() and io_start_multiplex_in(). */
33 /** If no timeout is specified then use a 60 second select timeout */
34 #define SELECT_TIMEOUT 60
37 extern size_t bwlimit_writemax;
38 extern int io_timeout;
42 extern int am_generator;
43 extern int inc_recurse;
48 extern int read_batch;
49 extern int protect_args;
50 extern int checksum_seed;
51 extern int protocol_version;
52 extern int remove_source_files;
53 extern int preserve_hard_links;
54 extern struct stats stats;
55 extern struct file_list *cur_flist;
57 extern int filesfrom_convert;
58 extern iconv_t ic_send, ic_recv;
61 int csum_length = SHORT_SUM_LENGTH; /* initial value */
63 int ignore_timeout = 0;
67 /* Ignore an EOF error if non-zero. See whine_about_eof(). */
68 int kluge_around_eof = 0;
75 static int iobuf_f_in = -1;
76 static char *iobuf_in;
77 static size_t iobuf_in_siz;
78 static size_t iobuf_in_ndx;
79 static size_t iobuf_in_remaining;
81 static int iobuf_f_out = -1;
82 static char *iobuf_out;
83 static int iobuf_out_cnt;
85 int flist_forward_from = -1;
87 static int io_multiplexing_out;
88 static int io_multiplexing_in;
89 static time_t last_io_in;
90 static time_t last_io_out;
93 static int write_batch_monitor_in = -1;
94 static int write_batch_monitor_out = -1;
96 static int io_filesfrom_f_in = -1;
97 static int io_filesfrom_f_out = -1;
98 static xbuf ff_buf = EMPTY_XBUF;
99 static char ff_lastchar;
101 static xbuf iconv_buf = EMPTY_XBUF;
103 static int defer_forwarding_messages = 0, defer_forwarding_keep = 0;
104 static int select_timeout = SELECT_TIMEOUT;
105 static int active_filecnt = 0;
106 static OFF_T active_bytecnt = 0;
107 static int first_message = 1;
109 static char int_byte_extra[64] = {
110 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* (00 - 3F)/4 */
111 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* (40 - 7F)/4 */
112 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* (80 - BF)/4 */
113 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 5, 6, /* (C0 - FF)/4 */
116 #define REMOTE_OPTION_ERROR "rsync: on remote machine: -"
117 #define REMOTE_OPTION_ERROR2 ": unknown option"
119 enum festatus { FES_SUCCESS, FES_REDO, FES_NO_SEND };
121 static void readfd(int fd, char *buffer, size_t N);
122 static void writefd(int fd, const char *buf, size_t len);
123 static void writefd_unbuffered(int fd, const char *buf, size_t len);
124 static void mplex_write(int fd, enum msgcode code, const char *buf, size_t len, int convert);
126 struct flist_ndx_item {
127 struct flist_ndx_item *next;
131 struct flist_ndx_list {
132 struct flist_ndx_item *head, *tail;
135 static struct flist_ndx_list redo_list, hlink_list;
137 struct msg_list_item {
138 struct msg_list_item *next;
144 struct msg_list_item *head, *tail;
147 static struct msg_list msg_queue;
149 static void flist_ndx_push(struct flist_ndx_list *lp, int ndx)
151 struct flist_ndx_item *item;
153 if (!(item = new(struct flist_ndx_item)))
154 out_of_memory("flist_ndx_push");
158 lp->tail->next = item;
164 static int flist_ndx_pop(struct flist_ndx_list *lp)
166 struct flist_ndx_item *next;
173 next = lp->head->next;
182 static void got_flist_entry_status(enum festatus status, const char *buf)
184 int ndx = IVAL(buf, 0);
185 struct file_list *flist = flist_for_ndx(ndx);
187 assert(flist != NULL);
189 if (remove_source_files) {
191 active_bytecnt -= F_LENGTH(flist->files[ndx - flist->ndx_start]);
195 flist->in_progress--;
199 if (remove_source_files)
200 send_msg(MSG_SUCCESS, buf, 4, 0);
201 if (preserve_hard_links) {
202 struct file_struct *file = flist->files[ndx - flist->ndx_start];
203 if (F_IS_HLINKED(file)) {
204 flist_ndx_push(&hlink_list, ndx);
205 flist->in_progress++;
212 flist_ndx_push(&redo_list, ndx);
219 static void check_timeout(void)
223 if (!io_timeout || ignore_timeout)
227 last_io_in = time(NULL);
233 if (t - last_io_in >= io_timeout) {
234 if (!am_server && !am_daemon) {
235 rprintf(FERROR, "io timeout after %d seconds -- exiting\n",
236 (int)(t-last_io_in));
238 exit_cleanup(RERR_TIMEOUT);
242 /* Note the fds used for the main socket (which might really be a pipe
243 * for a local transfer, but we can ignore that). */
244 void io_set_sock_fds(int f_in, int f_out)
250 void set_io_timeout(int secs)
254 if (!io_timeout || io_timeout > SELECT_TIMEOUT)
255 select_timeout = SELECT_TIMEOUT;
257 select_timeout = io_timeout;
259 allowed_lull = read_batch ? 0 : (io_timeout + 1) / 2;
262 /* Setup the fd used to receive MSG_* messages. Only needed during the
263 * early stages of being a local sender (up through the sending of the
264 * file list) or when we're the generator (to fetch the messages from
266 void set_msg_fd_in(int fd)
271 /* Setup the fd used to send our MSG_* messages. Only needed when
272 * we're the receiver (to send our messages to the generator). */
273 void set_msg_fd_out(int fd)
276 set_nonblocking(msg_fd_out);
279 /* Add a message to the pending MSG_* list. */
280 static void msg_list_add(struct msg_list *lst, int code, const char *buf, int len, int convert)
282 struct msg_list_item *m;
283 int sz = len + 4 + sizeof m[0] - 1;
285 if (!(m = (struct msg_list_item *)new_array(char, sz)))
286 out_of_memory("msg_list_add");
288 m->convert = convert;
289 SIVAL(m->buf, 0, ((code+MPLEX_BASE)<<24) | len);
290 memcpy(m->buf + 4, buf, len);
298 static void msg_flush(void)
301 while (msg_queue.head && io_multiplexing_out) {
302 struct msg_list_item *m = msg_queue.head;
303 int len = IVAL(m->buf, 0) & 0xFFFFFF;
304 int tag = *((uchar*)m->buf+3) - MPLEX_BASE;
305 if (!(msg_queue.head = m->next))
306 msg_queue.tail = NULL;
307 stats.total_written += len + 4;
308 defer_forwarding_messages++;
309 mplex_write(sock_f_out, tag, m->buf + 4, len, m->convert);
310 defer_forwarding_messages--;
314 while (msg_queue.head) {
315 struct msg_list_item *m = msg_queue.head;
316 int len = IVAL(m->buf, 0) & 0xFFFFFF;
317 int tag = *((uchar*)m->buf+3) - MPLEX_BASE;
318 if (!(msg_queue.head = m->next))
319 msg_queue.tail = NULL;
320 defer_forwarding_messages++;
321 mplex_write(msg_fd_out, tag, m->buf + 4, len, m->convert);
322 defer_forwarding_messages--;
328 static void check_for_d_option_error(const char *msg)
330 static char rsync263_opts[] = "BCDHIKLPRSTWabceghlnopqrtuvxz";
335 || strncmp(msg, REMOTE_OPTION_ERROR, sizeof REMOTE_OPTION_ERROR - 1) != 0)
338 msg += sizeof REMOTE_OPTION_ERROR - 1;
339 if (*msg == '-' || (colon = strchr(msg, ':')) == NULL
340 || strncmp(colon, REMOTE_OPTION_ERROR2, sizeof REMOTE_OPTION_ERROR2 - 1) != 0)
343 for ( ; *msg != ':'; msg++) {
346 else if (*msg == 'e')
348 else if (strchr(rsync263_opts, *msg) == NULL)
354 "*** Try using \"--old-d\" if remote rsync is <= 2.6.3 ***\n");
358 /* Read a message from the MSG_* fd and handle it. This is called either
359 * during the early stages of being a local sender (up through the sending
360 * of the file list) or when we're the generator (to fetch the messages
361 * from the receiver). */
362 static void read_msg_fd(void)
366 struct file_list *flist;
370 /* Temporarily disable msg_fd_in. This is needed to avoid looping back
371 * to this routine from writefd_unbuffered(). */
374 defer_forwarding_messages++;
379 len = tag & 0xFFFFFF;
380 tag = (tag >> 24) - MPLEX_BASE;
384 if (len < 0 || len > 1 || !am_generator) {
386 rprintf(FERROR, "invalid message %d:%d [%s%s]\n",
387 tag, len, who_am_i(),
388 inc_recurse ? "/inc" : "");
389 exit_cleanup(RERR_STREAMIO);
392 readfd(fd, buf, len);
393 stats.total_read = read_varlong(fd, 3);
398 if (len != 4 || !am_generator)
401 got_flist_entry_status(FES_REDO, buf);
404 if (len != 4 || !am_generator || !inc_recurse)
407 /* Read extra file list from receiver. */
408 assert(iobuf_in != NULL);
409 assert(iobuf_f_in == fd);
410 if (DEBUG_GTE(FLIST, 2)) {
411 rprintf(FINFO, "[%s] receiving flist for dir %d\n",
412 who_am_i(), IVAL(buf,0));
414 flist = recv_file_list(fd);
415 flist->parent_ndx = IVAL(buf,0);
416 #ifdef SUPPORT_HARD_LINKS
417 if (preserve_hard_links)
418 match_hard_links(flist);
422 if (len != 0 || !am_generator || !inc_recurse)
429 readfd(fd, buf, len);
430 io_error |= IVAL(buf, 0);
433 if (len >= (int)sizeof buf || !am_generator)
435 readfd(fd, buf, len);
436 send_msg(MSG_DELETED, buf, len, 1);
439 if (len != 4 || !am_generator)
442 got_flist_entry_status(FES_SUCCESS, buf);
445 if (len != 4 || !am_generator)
448 got_flist_entry_status(FES_NO_SEND, buf);
450 case MSG_ERROR_SOCKET:
454 if (tag == MSG_ERROR_SOCKET)
455 io_end_multiplex_out();
467 rwrite((enum logcode)tag, buf, n, !am_generator);
472 rprintf(FERROR, "unknown message %d:%d [%s]\n",
473 tag, len, who_am_i());
474 exit_cleanup(RERR_STREAMIO);
479 if (!--defer_forwarding_messages && !no_flush)
483 /* This is used by the generator to limit how many file transfers can
484 * be active at once when --remove-source-files is specified. Without
485 * this, sender-side deletions were mostly happening at the end. */
486 void increment_active_files(int ndx, int itemizing, enum logcode code)
488 /* TODO: tune these limits? */
489 while (active_filecnt >= (active_bytecnt >= 128*1024 ? 10 : 50)) {
490 check_for_finished_files(itemizing, code, 0);
492 io_flush(NORMAL_FLUSH);
498 active_bytecnt += F_LENGTH(cur_flist->files[ndx - cur_flist->ndx_start]);
501 /* Write an message to a multiplexed stream. If this fails, rsync exits. */
502 static void mplex_write(int fd, enum msgcode code, const char *buf, size_t len, int convert)
504 char buffer[BIGPATHBUFLEN]; /* Oversized for use by iconv code. */
508 /* We need to convert buf before doing anything else so that we
509 * can include the (converted) byte length in the message header. */
510 if (convert && ic_send != (iconv_t)-1) {
513 INIT_XBUF(outbuf, buffer + 4, 0, sizeof buffer - 4);
514 INIT_XBUF(inbuf, (char*)buf, len, (size_t)-1);
516 iconvbufs(ic_send, &inbuf, &outbuf,
517 ICB_INCLUDE_BAD | ICB_INCLUDE_INCOMPLETE);
519 rprintf(FERROR, "overflowed conversion buffer in mplex_write");
520 exit_cleanup(RERR_UNSUPPORTED);
523 n = len = outbuf.len;
526 if (n > 1024 - 4) /* BIGPATHBUFLEN can handle 1024 bytes */
527 n = 0; /* We'd rather do 2 writes than too much memcpy(). */
529 memcpy(buffer + 4, buf, n);
531 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
533 defer_forwarding_keep = 1; /* defer_forwarding_messages++ on return */
534 writefd_unbuffered(fd, buffer, n+4);
535 defer_forwarding_keep = 0;
538 writefd_unbuffered(fd, buf+n, len-n);
540 if (!--defer_forwarding_messages && !no_flush)
544 int send_msg(enum msgcode code, const char *buf, int len, int convert)
546 if (msg_fd_out < 0) {
547 if (!defer_forwarding_messages)
548 return io_multiplex_write(code, buf, len, convert);
549 if (!io_multiplexing_out)
551 msg_list_add(&msg_queue, code, buf, len, convert);
554 if (flist_forward_from >= 0)
555 msg_list_add(&msg_queue, code, buf, len, convert);
557 mplex_write(msg_fd_out, code, buf, len, convert);
561 void send_msg_int(enum msgcode code, int num)
564 SIVAL(numbuf, 0, num);
565 send_msg(code, numbuf, 4, 0);
568 void wait_for_receiver(void)
571 io_flush(NORMAL_FLUSH);
576 int get_redo_num(void)
578 return flist_ndx_pop(&redo_list);
581 int get_hlink_num(void)
583 return flist_ndx_pop(&hlink_list);
587 * When we're the receiver and we have a local --files-from list of names
588 * that needs to be sent over the socket to the sender, we have to do two
589 * things at the same time: send the sender a list of what files we're
590 * processing and read the incoming file+info list from the sender. We do
591 * this by augmenting the read_timeout() function to copy this data. It
592 * uses ff_buf to read a block of data from f_in (when it is ready, since
593 * it might be a pipe) and then blast it out f_out (when it is ready to
594 * receive more data).
596 void io_set_filesfrom_fds(int f_in, int f_out)
598 io_filesfrom_f_in = f_in;
599 io_filesfrom_f_out = f_out;
600 alloc_xbuf(&ff_buf, 2048);
603 alloc_xbuf(&iconv_buf, 1024);
607 /* It's almost always an error to get an EOF when we're trying to read from the
608 * network, because the protocol is (for the most part) self-terminating.
610 * There is one case for the receiver when it is at the end of the transfer
611 * (hanging around reading any keep-alive packets that might come its way): if
612 * the sender dies before the generator's kill-signal comes through, we can end
613 * up here needing to loop until the kill-signal arrives. In this situation,
614 * kluge_around_eof will be < 0.
616 * There is another case for older protocol versions (< 24) where the module
617 * listing was not terminated, so we must ignore an EOF error in that case and
618 * exit. In this situation, kluge_around_eof will be > 0. */
619 static void whine_about_eof(int fd)
621 if (kluge_around_eof && fd == sock_f_in) {
623 if (kluge_around_eof > 0)
625 /* If we're still here after 10 seconds, exit with an error. */
626 for (i = 10*1000/20; i--; )
630 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
631 "(%s bytes received so far) [%s]\n",
632 big_num(stats.total_read, 0), who_am_i());
634 exit_cleanup(RERR_STREAMIO);
638 * Read from a socket with I/O timeout. return the number of bytes
639 * read. If no bytes can be read then exit, never return a number <= 0.
641 * TODO: If the remote shell connection fails, then current versions
642 * actually report an "unexpected EOF" error here. Since it's a
643 * fairly common mistake to try to use rsh when ssh is required, we
644 * should trap that: if we fail to read any data at all, we should
645 * give a better explanation. We can tell whether the connection has
646 * started by looking e.g. at whether the remote version is known yet.
648 static int read_timeout(int fd, char *buf, size_t len)
652 io_flush(FULL_FLUSH);
655 /* until we manage to read *something* */
664 if (io_filesfrom_f_out >= 0) {
666 if (ff_buf.len == 0) {
667 if (io_filesfrom_f_in >= 0) {
668 FD_SET(io_filesfrom_f_in, &r_fds);
669 new_fd = io_filesfrom_f_in;
671 io_filesfrom_f_out = -1;
675 FD_SET(io_filesfrom_f_out, &w_fds);
676 new_fd = io_filesfrom_f_out;
682 tv.tv_sec = select_timeout;
687 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
690 if (errno == EBADF) {
691 defer_forwarding_messages = 0;
692 exit_cleanup(RERR_SOCKETIO);
698 if (io_filesfrom_f_out >= 0) {
700 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
701 int l = write(io_filesfrom_f_out,
702 ff_buf.buf + ff_buf.pos,
705 if (!(ff_buf.len -= l))
709 } else if (errno != EINTR) {
710 /* XXX should we complain? */
711 io_filesfrom_f_out = -1;
714 } else if (io_filesfrom_f_in >= 0) {
715 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
717 xbuf *ibuf = filesfrom_convert ? &iconv_buf : &ff_buf;
719 xbuf *ibuf = &ff_buf;
721 int l = read(io_filesfrom_f_in, ibuf->buf, ibuf->size);
723 if (l == 0 || errno != EINTR) {
724 /* Send end-of-file marker */
725 memcpy(ff_buf.buf, "\0\0", 2);
726 ff_buf.len = ff_lastchar? 2 : 1;
728 io_filesfrom_f_in = -1;
732 if (filesfrom_convert) {
735 iconvbufs(ic_send, &iconv_buf, &ff_buf,
736 ICB_EXPAND_OUT|ICB_INCLUDE_BAD|ICB_INCLUDE_INCOMPLETE);
741 char *s = ff_buf.buf + l;
742 /* Transform CR and/or LF into '\0' */
743 while (s-- > ff_buf.buf) {
744 if (*s == '\n' || *s == '\r')
749 /* Last buf ended with a '\0', so don't
750 * let this buf start with one. */
751 while (l && ff_buf.buf[ff_buf.pos] == '\0')
757 char *f = ff_buf.buf + ff_buf.pos;
760 /* Eliminate any multi-'\0' runs. */
762 if (!(*t++ = *f++)) {
763 while (f != eob && !*f)
775 if (!FD_ISSET(fd, &r_fds))
778 n = read(fd, buf, len);
782 whine_about_eof(fd); /* Doesn't return. */
783 if (errno == EINTR || errno == EWOULDBLOCK
787 /* Don't write errors on a dead socket. */
788 if (fd == sock_f_in) {
789 io_end_multiplex_out();
790 rsyserr(FERROR_SOCKET, errno, "read error");
792 rsyserr(FERROR, errno, "read error");
793 exit_cleanup(RERR_STREAMIO);
800 if (fd == sock_f_in && io_timeout)
801 last_io_in = time(NULL);
807 /* Read a line into the "buf" buffer. */
808 int read_line(int fd, char *buf, size_t bufsiz, int flags)
814 if (flags & RL_CONVERT && iconv_buf.size < bufsiz)
815 realloc_xbuf(&iconv_buf, bufsiz + 1024);
820 s = flags & RL_CONVERT ? iconv_buf.buf : buf;
824 eob = s + bufsiz - 1;
826 cnt = read(fd, &ch, 1);
827 if (cnt < 0 && (errno == EWOULDBLOCK
828 || errno == EINTR || errno == EAGAIN)) {
835 tv.tv_sec = select_timeout;
837 if (!select(fd+1, &r_fds, NULL, &e_fds, &tv))
839 /*if (FD_ISSET(fd, &e_fds))
840 rprintf(FINFO, "select exception on fd %d\n", fd); */
845 if (flags & RL_EOL_NULLS ? ch == '\0' : (ch == '\r' || ch == '\n')) {
846 /* Skip empty lines if dumping comments. */
847 if (flags & RL_DUMP_COMMENTS && s == buf)
856 if (flags & RL_DUMP_COMMENTS && (*buf == '#' || *buf == ';'))
860 if (flags & RL_CONVERT) {
862 INIT_XBUF(outbuf, buf, 0, bufsiz);
864 iconv_buf.len = s - iconv_buf.buf;
865 iconvbufs(ic_recv, &iconv_buf, &outbuf,
866 ICB_INCLUDE_BAD | ICB_INCLUDE_INCOMPLETE);
867 outbuf.buf[outbuf.len] = '\0';
875 void read_args(int f_in, char *mod_name, char *buf, size_t bufsiz, int rl_nulls,
876 char ***argv_p, int *argc_p, char **request_p)
878 int maxargs = MAX_ARGS;
882 int rl_flags = (rl_nulls ? RL_EOL_NULLS : 0);
885 rl_flags |= (protect_args && ic_recv != (iconv_t)-1 ? RL_CONVERT : 0);
888 if (!(argv = new_array(char *, maxargs)))
889 out_of_memory("read_args");
890 if (mod_name && !protect_args)
891 argv[argc++] = "rsyncd";
894 if (read_line(f_in, buf, bufsiz, rl_flags) == 0)
897 if (argc == maxargs-1) {
899 if (!(argv = realloc_array(argv, char *, maxargs)))
900 out_of_memory("read_args");
905 *request_p = strdup(buf);
909 glob_expand_module(mod_name, buf, &argv, &argc, &maxargs);
911 glob_expand(buf, &argv, &argc, &maxargs);
913 if (!(p = strdup(buf)))
914 out_of_memory("read_args");
916 if (*p == '.' && p[1] == '\0')
922 glob_expand(NULL, NULL, NULL, NULL);
928 int io_start_buffering_out(int f_out)
931 assert(f_out == iobuf_f_out);
934 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
935 out_of_memory("io_start_buffering_out");
941 int io_start_buffering_in(int f_in)
944 assert(f_in == iobuf_f_in);
947 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
948 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
949 out_of_memory("io_start_buffering_in");
954 void io_end_buffering_in(void)
961 iobuf_in_remaining = 0;
965 void io_end_buffering_out(void)
969 io_flush(FULL_FLUSH);
975 void maybe_flush_socket(int important)
977 if (iobuf_out && iobuf_out_cnt
978 && (important || time(NULL) - last_io_out >= 5))
979 io_flush(NORMAL_FLUSH);
982 void maybe_send_keepalive(void)
984 if (time(NULL) - last_io_out >= allowed_lull) {
985 if (!iobuf_out || !iobuf_out_cnt) {
986 if (protocol_version < 29)
987 return; /* there's nothing we can do */
988 if (protocol_version >= 30)
989 send_msg(MSG_NOOP, "", 0, 0);
991 write_int(sock_f_out, cur_flist->used);
992 write_shortint(sock_f_out, ITEM_IS_NEW);
996 io_flush(NORMAL_FLUSH);
1000 void start_flist_forward(int f_in)
1002 assert(iobuf_out != NULL);
1003 assert(iobuf_f_out == msg_fd_out);
1004 flist_forward_from = f_in;
1007 void stop_flist_forward()
1009 flist_forward_from = -1;
1010 io_flush(FULL_FLUSH);
1014 * Continue trying to read len bytes - don't return until len has been
1017 static void read_loop(int fd, char *buf, size_t len)
1020 int n = read_timeout(fd, buf, len);
1028 * Read from the file descriptor handling multiplexing - return number
1031 * Never returns <= 0.
1033 static int readfd_unbuffered(int fd, char *buf, size_t len)
1037 char line[BIGPATHBUFLEN];
1039 if (!iobuf_in || fd != iobuf_f_in)
1040 return read_timeout(fd, buf, len);
1042 if (!io_multiplexing_in && iobuf_in_remaining == 0) {
1043 iobuf_in_remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
1048 if (iobuf_in_remaining) {
1049 len = MIN(len, iobuf_in_remaining);
1050 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
1051 iobuf_in_ndx += len;
1052 iobuf_in_remaining -= len;
1057 read_loop(fd, line, 4);
1058 tag = IVAL(line, 0);
1060 msg_bytes = tag & 0xFFFFFF;
1061 tag = (tag >> 24) - MPLEX_BASE;
1065 if (msg_bytes > iobuf_in_siz) {
1066 if (!(iobuf_in = realloc_array(iobuf_in, char,
1068 out_of_memory("readfd_unbuffered");
1069 iobuf_in_siz = msg_bytes;
1071 read_loop(fd, iobuf_in, msg_bytes);
1072 iobuf_in_remaining = msg_bytes;
1077 maybe_send_keepalive();
1082 read_loop(fd, line, msg_bytes);
1083 send_msg_int(MSG_IO_ERROR, IVAL(line, 0));
1084 io_error |= IVAL(line, 0);
1087 if (msg_bytes >= sizeof line)
1090 if (ic_recv != (iconv_t)-1) {
1095 INIT_CONST_XBUF(outbuf, line);
1096 INIT_XBUF(inbuf, ibuf, 0, (size_t)-1);
1099 inbuf.len = msg_bytes > sizeof ibuf
1100 ? sizeof ibuf : msg_bytes;
1101 read_loop(fd, inbuf.buf, inbuf.len);
1102 if (!(msg_bytes -= inbuf.len)
1103 && !ibuf[inbuf.len-1])
1104 inbuf.len--, add_null = 1;
1105 if (iconvbufs(ic_send, &inbuf, &outbuf,
1106 ICB_INCLUDE_BAD | ICB_INCLUDE_INCOMPLETE) < 0)
1110 if (outbuf.len == outbuf.size)
1112 outbuf.buf[outbuf.len++] = '\0';
1114 msg_bytes = outbuf.len;
1117 read_loop(fd, line, msg_bytes);
1118 /* A directory name was sent with the trailing null */
1119 if (msg_bytes > 0 && !line[msg_bytes-1])
1120 log_delete(line, S_IFDIR);
1122 line[msg_bytes] = '\0';
1123 log_delete(line, S_IFREG);
1127 if (msg_bytes != 4) {
1129 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
1130 tag, (long)msg_bytes, who_am_i());
1131 exit_cleanup(RERR_STREAMIO);
1133 read_loop(fd, line, msg_bytes);
1134 successful_send(IVAL(line, 0));
1139 read_loop(fd, line, msg_bytes);
1140 send_msg_int(MSG_NO_SEND, IVAL(line, 0));
1144 case MSG_ERROR_XFER:
1146 if (msg_bytes >= sizeof line) {
1149 "multiplexing overflow %d:%ld [%s]\n",
1150 tag, (long)msg_bytes, who_am_i());
1151 exit_cleanup(RERR_STREAMIO);
1153 read_loop(fd, line, msg_bytes);
1154 rwrite((enum logcode)tag, line, msg_bytes, 1);
1155 if (first_message) {
1156 if (list_only && !am_sender && tag == 1) {
1157 line[msg_bytes] = '\0';
1158 check_for_d_option_error(line);
1164 rprintf(FERROR, "unexpected tag %d [%s]\n",
1166 exit_cleanup(RERR_STREAMIO);
1170 if (iobuf_in_remaining == 0)
1171 io_flush(NORMAL_FLUSH);
1176 /* Do a buffered read from fd. Don't return until all N bytes have
1177 * been read. If all N can't be read then exit with an error. */
1178 static void readfd(int fd, char *buffer, size_t N)
1184 cnt = readfd_unbuffered(fd, buffer + total, N-total);
1188 if (fd == write_batch_monitor_in) {
1189 if ((size_t)write(batch_fd, buffer, total) != total)
1190 exit_cleanup(RERR_FILEIO);
1193 if (fd == flist_forward_from)
1194 writefd(iobuf_f_out, buffer, total);
1196 if (fd == sock_f_in)
1197 stats.total_read += total;
1200 unsigned short read_shortint(int f)
1204 return (UVAL(b, 1) << 8) + UVAL(b, 0);
1207 int32 read_int(int f)
1214 #if SIZEOF_INT32 > 4
1215 if (num & (int32)0x80000000)
1216 num |= ~(int32)0xffffffff;
1221 int32 read_varint(int f)
1231 readfd(f, (char*)&ch, 1);
1232 extra = int_byte_extra[ch / 4];
1234 uchar bit = ((uchar)1<<(8-extra));
1235 if (extra >= (int)sizeof u.b) {
1236 rprintf(FERROR, "Overflow in read_varint()\n");
1237 exit_cleanup(RERR_STREAMIO);
1239 readfd(f, u.b, extra);
1240 u.b[extra] = ch & (bit-1);
1243 #if CAREFUL_ALIGNMENT
1246 #if SIZEOF_INT32 > 4
1247 if (u.x & (int32)0x80000000)
1248 u.x |= ~(int32)0xffffffff;
1253 int64 read_varlong(int f, uchar min_bytes)
1262 #if SIZEOF_INT64 < 8
1267 readfd(f, b2, min_bytes);
1268 memcpy(u.b, b2+1, min_bytes-1);
1269 extra = int_byte_extra[CVAL(b2, 0) / 4];
1271 uchar bit = ((uchar)1<<(8-extra));
1272 if (min_bytes + extra > (int)sizeof u.b) {
1273 rprintf(FERROR, "Overflow in read_varlong()\n");
1274 exit_cleanup(RERR_STREAMIO);
1276 readfd(f, u.b + min_bytes - 1, extra);
1277 u.b[min_bytes + extra - 1] = CVAL(b2, 0) & (bit-1);
1278 #if SIZEOF_INT64 < 8
1279 if (min_bytes + extra > 5 || u.b[4] || CVAL(u.b,3) & 0x80) {
1280 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1281 exit_cleanup(RERR_UNSUPPORTED);
1285 u.b[min_bytes + extra - 1] = CVAL(b2, 0);
1286 #if SIZEOF_INT64 < 8
1288 #elif CAREFUL_ALIGNMENT
1289 u.x = IVAL(u.b,0) | (((int64)IVAL(u.b,4))<<32);
1294 int64 read_longint(int f)
1296 #if SIZEOF_INT64 >= 8
1299 int32 num = read_int(f);
1301 if (num != (int32)0xffffffff)
1304 #if SIZEOF_INT64 < 8
1305 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1306 exit_cleanup(RERR_UNSUPPORTED);
1309 return IVAL(b,0) | (((int64)IVAL(b,4))<<32);
1313 void read_buf(int f, char *buf, size_t len)
1318 void read_sbuf(int f, char *buf, size_t len)
1320 readfd(f, buf, len);
1324 uchar read_byte(int f)
1327 readfd(f, (char *)&c, 1);
1331 int read_vstring(int f, char *buf, int bufsize)
1333 int len = read_byte(f);
1336 len = (len & ~0x80) * 0x100 + read_byte(f);
1338 if (len >= bufsize) {
1339 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
1345 readfd(f, buf, len);
1350 /* Populate a sum_struct with values from the socket. This is
1351 * called by both the sender and the receiver. */
1352 void read_sum_head(int f, struct sum_struct *sum)
1354 int32 max_blength = protocol_version < 30 ? OLD_MAX_BLOCK_SIZE : MAX_BLOCK_SIZE;
1355 sum->count = read_int(f);
1356 if (sum->count < 0) {
1357 rprintf(FERROR, "Invalid checksum count %ld [%s]\n",
1358 (long)sum->count, who_am_i());
1359 exit_cleanup(RERR_PROTOCOL);
1361 sum->blength = read_int(f);
1362 if (sum->blength < 0 || sum->blength > max_blength) {
1363 rprintf(FERROR, "Invalid block length %ld [%s]\n",
1364 (long)sum->blength, who_am_i());
1365 exit_cleanup(RERR_PROTOCOL);
1367 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
1368 if (sum->s2length < 0 || sum->s2length > MAX_DIGEST_LEN) {
1369 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
1370 sum->s2length, who_am_i());
1371 exit_cleanup(RERR_PROTOCOL);
1373 sum->remainder = read_int(f);
1374 if (sum->remainder < 0 || sum->remainder > sum->blength) {
1375 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
1376 (long)sum->remainder, who_am_i());
1377 exit_cleanup(RERR_PROTOCOL);
1381 /* Send the values from a sum_struct over the socket. Set sum to
1382 * NULL if there are no checksums to send. This is called by both
1383 * the generator and the sender. */
1384 void write_sum_head(int f, struct sum_struct *sum)
1386 static struct sum_struct null_sum;
1391 write_int(f, sum->count);
1392 write_int(f, sum->blength);
1393 if (protocol_version >= 27)
1394 write_int(f, sum->s2length);
1395 write_int(f, sum->remainder);
1399 * Sleep after writing to limit I/O bandwidth usage.
1401 * @todo Rather than sleeping after each write, it might be better to
1402 * use some kind of averaging. The current algorithm seems to always
1403 * use a bit less bandwidth than specified, because it doesn't make up
1404 * for slow periods. But arguably this is a feature. In addition, we
1405 * ought to take the time used to write the data into account.
1407 * During some phases of big transfers (file FOO is uptodate) this is
1408 * called with a small bytes_written every time. As the kernel has to
1409 * round small waits up to guarantee that we actually wait at least the
1410 * requested number of microseconds, this can become grossly inaccurate.
1411 * We therefore keep track of the bytes we've written over time and only
1412 * sleep when the accumulated delay is at least 1 tenth of a second.
1414 static void sleep_for_bwlimit(int bytes_written)
1416 static struct timeval prior_tv;
1417 static long total_written = 0;
1418 struct timeval tv, start_tv;
1419 long elapsed_usec, sleep_usec;
1421 #define ONE_SEC 1000000L /* # of microseconds in a second */
1423 if (!bwlimit_writemax)
1426 total_written += bytes_written;
1428 gettimeofday(&start_tv, NULL);
1429 if (prior_tv.tv_sec) {
1430 elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
1431 + (start_tv.tv_usec - prior_tv.tv_usec);
1432 total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
1433 if (total_written < 0)
1437 sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
1438 if (sleep_usec < ONE_SEC / 10) {
1439 prior_tv = start_tv;
1443 tv.tv_sec = sleep_usec / ONE_SEC;
1444 tv.tv_usec = sleep_usec % ONE_SEC;
1445 select(0, NULL, NULL, NULL, &tv);
1447 gettimeofday(&prior_tv, NULL);
1448 elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
1449 + (prior_tv.tv_usec - start_tv.tv_usec);
1450 total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
1453 /* Write len bytes to the file descriptor fd, looping as necessary to get
1454 * the job done and also (in certain circumstances) reading any data on
1455 * msg_fd_in to avoid deadlock.
1457 * This function underlies the multiplexing system. The body of the
1458 * application never calls this function directly. */
1459 static void writefd_unbuffered(int fd, const char *buf, size_t len)
1461 size_t n, total = 0;
1462 fd_set w_fds, r_fds, e_fds;
1463 int maxfd, count, cnt, using_r_fds;
1468 defer_forwarding_messages++, defer_inc++;
1470 while (total < len) {
1477 if (msg_fd_in >= 0) {
1479 FD_SET(msg_fd_in, &r_fds);
1480 if (msg_fd_in > maxfd)
1486 tv.tv_sec = select_timeout;
1490 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1491 &w_fds, &e_fds, &tv);
1494 if (count < 0 && errno == EBADF)
1495 exit_cleanup(RERR_SOCKETIO);
1500 /*if (FD_ISSET(fd, &e_fds))
1501 rprintf(FINFO, "select exception on fd %d\n", fd); */
1503 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1506 if (!FD_ISSET(fd, &w_fds))
1510 if (bwlimit_writemax && n > bwlimit_writemax)
1511 n = bwlimit_writemax;
1512 cnt = write(fd, buf + total, n);
1518 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1524 /* Don't try to write errors back across the stream. */
1525 if (fd == sock_f_out)
1526 io_end_multiplex_out();
1527 /* Don't try to write errors down a failing msg pipe. */
1528 if (am_server && fd == msg_fd_out)
1529 exit_cleanup(RERR_STREAMIO);
1530 rsyserr(FERROR, errno,
1531 "writefd_unbuffered failed to write %ld bytes [%s]",
1532 (long)len, who_am_i());
1533 /* If the other side is sending us error messages, try
1534 * to grab any messages they sent before they died. */
1535 while (!am_server && fd == sock_f_out && io_multiplexing_in) {
1539 readfd_unbuffered(sock_f_in, buf, sizeof buf);
1541 exit_cleanup(RERR_STREAMIO);
1545 defer_forwarding_messages++, defer_inc++;
1547 if (fd == sock_f_out) {
1548 if (io_timeout || am_generator)
1549 last_io_out = time(NULL);
1550 sleep_for_bwlimit(cnt);
1555 defer_inc -= defer_forwarding_keep;
1556 if (!(defer_forwarding_messages -= defer_inc) && !no_flush)
1560 void io_flush(int flush_it_all)
1562 if (!iobuf_out_cnt || no_flush)
1565 if (io_multiplexing_out)
1566 mplex_write(sock_f_out, MSG_DATA, iobuf_out, iobuf_out_cnt, 0);
1568 writefd_unbuffered(iobuf_f_out, iobuf_out, iobuf_out_cnt);
1571 if (flush_it_all && !defer_forwarding_messages)
1575 static void writefd(int fd, const char *buf, size_t len)
1577 if (fd == sock_f_out)
1578 stats.total_written += len;
1580 if (fd == write_batch_monitor_out) {
1581 if ((size_t)write(batch_fd, buf, len) != len)
1582 exit_cleanup(RERR_FILEIO);
1585 if (!iobuf_out || fd != iobuf_f_out) {
1586 writefd_unbuffered(fd, buf, len);
1591 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1593 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1599 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1600 io_flush(NORMAL_FLUSH);
1604 void write_shortint(int f, unsigned short x)
1608 b[1] = (char)(x >> 8);
1612 void write_int(int f, int32 x)
1619 void write_varint(int f, int32 x)
1627 while (cnt > 1 && b[cnt] == 0)
1629 bit = ((uchar)1<<(7-cnt+1));
1630 if (CVAL(b, cnt) >= bit) {
1634 *b = b[cnt] | ~(bit*2-1);
1641 void write_varlong(int f, int64 x, uchar min_bytes)
1648 #if SIZEOF_INT64 >= 8
1649 SIVAL(b, 5, x >> 32);
1651 if (x <= 0x7FFFFFFF && x >= 0)
1652 memset(b + 5, 0, 4);
1654 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1655 exit_cleanup(RERR_UNSUPPORTED);
1659 while (cnt > min_bytes && b[cnt] == 0)
1661 bit = ((uchar)1<<(7-cnt+min_bytes));
1662 if (CVAL(b, cnt) >= bit) {
1665 } else if (cnt > min_bytes)
1666 *b = b[cnt] | ~(bit*2-1);
1674 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1675 * 64-bit types on this platform.
1677 void write_longint(int f, int64 x)
1679 char b[12], * const s = b+4;
1682 if (x <= 0x7FFFFFFF && x >= 0) {
1687 #if SIZEOF_INT64 < 8
1688 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1689 exit_cleanup(RERR_UNSUPPORTED);
1692 SIVAL(s, 4, x >> 32);
1697 void write_buf(int f, const char *buf, size_t len)
1702 /** Write a string to the connection */
1703 void write_sbuf(int f, const char *buf)
1705 writefd(f, buf, strlen(buf));
1708 void write_byte(int f, uchar c)
1710 writefd(f, (char *)&c, 1);
1713 void write_vstring(int f, const char *str, int len)
1715 uchar lenbuf[3], *lb = lenbuf;
1720 "attempting to send over-long vstring (%d > %d)\n",
1722 exit_cleanup(RERR_PROTOCOL);
1724 *lb++ = len / 0x100 + 0x80;
1728 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1730 writefd(f, str, len);
1733 /* Send a file-list index using a byte-reduction method. */
1734 void write_ndx(int f, int32 ndx)
1736 static int32 prev_positive = -1, prev_negative = 1;
1737 int32 diff, cnt = 0;
1740 if (protocol_version < 30 || read_batch) {
1745 /* Send NDX_DONE as a single-byte 0 with no side effects. Send
1746 * negative nums as a positive after sending a leading 0xFF. */
1748 diff = ndx - prev_positive;
1749 prev_positive = ndx;
1750 } else if (ndx == NDX_DONE) {
1755 b[cnt++] = (char)0xFF;
1757 diff = ndx - prev_negative;
1758 prev_negative = ndx;
1761 /* A diff of 1 - 253 is sent as a one-byte diff; a diff of 254 - 32767
1762 * or 0 is sent as a 0xFE + a two-byte diff; otherwise we send 0xFE
1763 * & all 4 bytes of the (non-negative) num with the high-bit set. */
1764 if (diff < 0xFE && diff > 0)
1765 b[cnt++] = (char)diff;
1766 else if (diff < 0 || diff > 0x7FFF) {
1767 b[cnt++] = (char)0xFE;
1768 b[cnt++] = (char)((ndx >> 24) | 0x80);
1769 b[cnt++] = (char)ndx;
1770 b[cnt++] = (char)(ndx >> 8);
1771 b[cnt++] = (char)(ndx >> 16);
1773 b[cnt++] = (char)0xFE;
1774 b[cnt++] = (char)(diff >> 8);
1775 b[cnt++] = (char)diff;
1780 /* Receive a file-list index using a byte-reduction method. */
1781 int32 read_ndx(int f)
1783 static int32 prev_positive = -1, prev_negative = 1;
1784 int32 *prev_ptr, num;
1787 if (protocol_version < 30)
1791 if (CVAL(b, 0) == 0xFF) {
1793 prev_ptr = &prev_negative;
1794 } else if (CVAL(b, 0) == 0)
1797 prev_ptr = &prev_positive;
1798 if (CVAL(b, 0) == 0xFE) {
1800 if (CVAL(b, 0) & 0x80) {
1801 b[3] = CVAL(b, 0) & ~0x80;
1806 num = (UVAL(b,0)<<8) + UVAL(b,1) + *prev_ptr;
1808 num = UVAL(b, 0) + *prev_ptr;
1810 if (prev_ptr == &prev_negative)
1815 /* Read a line of up to bufsiz-1 characters into buf. Strips
1816 * the (required) trailing newline and all carriage returns.
1817 * Returns 1 for success; 0 for I/O error or truncation. */
1818 int read_line_old(int f, char *buf, size_t bufsiz)
1820 bufsiz--; /* leave room for the null */
1821 while (bufsiz > 0) {
1823 read_buf(f, buf, 1);
1828 if (buf[0] != '\r') {
1837 void io_printf(int fd, const char *format, ...)
1840 char buf[BIGPATHBUFLEN];
1843 va_start(ap, format);
1844 len = vsnprintf(buf, sizeof buf, format, ap);
1848 exit_cleanup(RERR_STREAMIO);
1850 if (len > (int)sizeof buf) {
1851 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1852 exit_cleanup(RERR_STREAMIO);
1855 write_sbuf(fd, buf);
1858 /** Setup for multiplexing a MSG_* stream with the data stream. */
1859 void io_start_multiplex_out(void)
1861 io_flush(NORMAL_FLUSH);
1862 io_start_buffering_out(sock_f_out);
1863 io_multiplexing_out = 1;
1866 /** Setup for multiplexing a MSG_* stream with the data stream. */
1867 void io_start_multiplex_in(void)
1869 io_flush(NORMAL_FLUSH);
1870 io_start_buffering_in(sock_f_in);
1871 io_multiplexing_in = 1;
1874 /** Write an message to the multiplexed data stream. */
1875 int io_multiplex_write(enum msgcode code, const char *buf, size_t len, int convert)
1877 if (!io_multiplexing_out)
1879 io_flush(NORMAL_FLUSH);
1880 stats.total_written += (len+4);
1881 mplex_write(sock_f_out, code, buf, len, convert);
1885 void io_end_multiplex_in(void)
1887 io_multiplexing_in = 0;
1888 io_end_buffering_in();
1891 /** Stop output multiplexing. */
1892 void io_end_multiplex_out(void)
1894 io_multiplexing_out = 0;
1895 io_end_buffering_out();
1898 void start_write_batch(int fd)
1900 /* Some communication has already taken place, but we don't
1901 * enable batch writing until here so that we can write a
1902 * canonical record of the communication even though the
1903 * actual communication so far depends on whether a daemon
1905 write_int(batch_fd, protocol_version);
1906 if (protocol_version >= 30)
1907 write_byte(batch_fd, inc_recurse);
1908 write_int(batch_fd, checksum_seed);
1911 write_batch_monitor_out = fd;
1913 write_batch_monitor_in = fd;
1916 void stop_write_batch(void)
1918 write_batch_monitor_out = -1;
1919 write_batch_monitor_in = -1;