1 /* -*- c-file-style: "linux" -*-
3 * Copyright (C) 1996-2001 by Andrew Tridgell
4 * Copyright (C) Paul Mackerras 1996
5 * Copyright (C) 2001, 2002 by Martin Pool <mbp@samba.org>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 * Socket and pipe I/O utilities used in rsync.
27 * rsync provides its own multiplexing system, which is used to send
28 * stderr and stdout over a single socket. We need this because
29 * stdout normally carries the binary data stream, and stderr all our
32 * For historical reasons this is off during the start of the
33 * connection, but it's switched on quite early using
34 * io_start_multiplex_out() and io_start_multiplex_in().
39 /** If no timeout is specified then use a 60 second select timeout */
40 #define SELECT_TIMEOUT 60
43 extern size_t bwlimit_writemax;
45 extern int io_timeout;
46 extern int allowed_lull;
50 extern int am_generator;
52 extern int read_batch;
53 extern int csum_length;
54 extern int checksum_seed;
55 extern int protocol_version;
56 extern int remove_sent_files;
57 extern int preserve_hard_links;
58 extern char *filesfrom_host;
59 extern struct stats stats;
60 extern struct file_list *the_file_list;
62 const char phase_unknown[] = "unknown";
63 int ignore_timeout = 0;
65 int batch_gen_fd = -1;
68 * The connection might be dropped at some point; perhaps because the
69 * remote instance crashed. Just giving the offset on the stream is
70 * not very helpful. So instead we try to make io_phase_name point to
73 * For buffered/multiplexed I/O these names will be somewhat
74 * approximate; perhaps for ease of support we would rather make the
75 * buffer always flush when a single application-level I/O finishes.
77 * @todo Perhaps we want some simple stack functionality, but there's
78 * no need to overdo it.
80 const char *io_write_phase = phase_unknown;
81 const char *io_read_phase = phase_unknown;
83 /* Ignore an EOF error if non-zero. See whine_about_eof(). */
84 int kluge_around_eof = 0;
91 static int io_multiplexing_out;
92 static int io_multiplexing_in;
93 static time_t last_io_in;
94 static time_t last_io_out;
97 static int write_batch_monitor_in = -1;
98 static int write_batch_monitor_out = -1;
100 static int io_filesfrom_f_in = -1;
101 static int io_filesfrom_f_out = -1;
102 static char io_filesfrom_buf[2048];
103 static char *io_filesfrom_bp;
104 static char io_filesfrom_lastchar;
105 static int io_filesfrom_buflen;
106 static size_t contiguous_write_len = 0;
107 static int select_timeout = SELECT_TIMEOUT;
109 static void read_loop(int fd, char *buf, size_t len);
111 struct flist_ndx_item {
112 struct flist_ndx_item *next;
116 struct flist_ndx_list {
117 struct flist_ndx_item *head, *tail;
120 static struct flist_ndx_list redo_list, hlink_list;
122 struct msg_list_item {
123 struct msg_list_item *next;
129 struct msg_list_item *head, *tail;
132 static struct msg_list msg_list;
134 static void flist_ndx_push(struct flist_ndx_list *lp, int ndx)
136 struct flist_ndx_item *item;
138 if (!(item = new(struct flist_ndx_item)))
139 out_of_memory("flist_ndx_push");
143 lp->tail->next = item;
149 static int flist_ndx_pop(struct flist_ndx_list *lp)
151 struct flist_ndx_item *next;
158 next = lp->head->next;
167 static void check_timeout(void)
171 if (!io_timeout || ignore_timeout)
175 last_io_in = time(NULL);
181 if (t - last_io_in >= io_timeout) {
182 if (!am_server && !am_daemon) {
183 rprintf(FERROR, "io timeout after %d seconds -- exiting\n",
184 (int)(t-last_io_in));
186 exit_cleanup(RERR_TIMEOUT);
190 /* Note the fds used for the main socket (which might really be a pipe
191 * for a local transfer, but we can ignore that). */
192 void io_set_sock_fds(int f_in, int f_out)
198 void set_io_timeout(int secs)
202 if (!io_timeout || io_timeout > SELECT_TIMEOUT)
203 select_timeout = SELECT_TIMEOUT;
205 select_timeout = io_timeout;
207 allowed_lull = read_batch ? 0 : (io_timeout + 1) / 2;
210 /* Setup the fd used to receive MSG_* messages. Only needed during the
211 * early stages of being a local sender (up through the sending of the
212 * file list) or when we're the generator (to fetch the messages from
214 void set_msg_fd_in(int fd)
219 /* Setup the fd used to send our MSG_* messages. Only needed when
220 * we're the receiver (to send our messages to the generator). */
221 void set_msg_fd_out(int fd)
224 set_nonblocking(msg_fd_out);
227 /* Add a message to the pending MSG_* list. */
228 static void msg_list_add(int code, char *buf, int len)
230 struct msg_list_item *ml;
232 if (!(ml = new(struct msg_list_item)))
233 out_of_memory("msg_list_add");
235 if (!(ml->buf = new_array(char, len+4)))
236 out_of_memory("msg_list_add");
237 SIVAL(ml->buf, 0, ((code+MPLEX_BASE)<<24) | len);
238 memcpy(ml->buf+4, buf, len);
241 msg_list.tail->next = ml;
247 /* Read a message from the MSG_* fd and handle it. This is called either
248 * during the early stages of being a local sender (up through the sending
249 * of the file list) or when we're the generator (to fetch the messages
250 * from the receiver). */
251 static void read_msg_fd(void)
258 /* Temporarily disable msg_fd_in. This is needed to avoid looping back
259 * to this routine from writefd_unbuffered(). */
262 read_loop(fd, buf, 4);
265 len = tag & 0xFFFFFF;
266 tag = (tag >> 24) - MPLEX_BASE;
270 if (len != 0 || !am_generator) {
271 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
272 exit_cleanup(RERR_STREAMIO);
274 flist_ndx_push(&redo_list, -1);
277 if (len != 4 || !am_generator) {
278 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
279 exit_cleanup(RERR_STREAMIO);
281 read_loop(fd, buf, 4);
282 flist_ndx_push(&redo_list, IVAL(buf,0));
285 if (len >= (int)sizeof buf || !am_generator) {
286 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
287 exit_cleanup(RERR_STREAMIO);
289 read_loop(fd, buf, len);
290 io_multiplex_write(MSG_DELETED, buf, len);
293 if (len != 4 || !am_generator) {
294 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
295 exit_cleanup(RERR_STREAMIO);
297 read_loop(fd, buf, len);
298 if (remove_sent_files)
299 io_multiplex_write(MSG_SUCCESS, buf, len);
300 if (preserve_hard_links)
301 flist_ndx_push(&hlink_list, IVAL(buf,0));
310 read_loop(fd, buf, n);
311 rwrite((enum logcode)tag, buf, n);
316 rprintf(FERROR, "unknown message %d:%d\n", tag, len);
317 exit_cleanup(RERR_STREAMIO);
323 /* Try to push messages off the list onto the wire. If we leave with more
324 * to do, return 0. On error, return -1. If everything flushed, return 1.
325 * This is only active in the receiver. */
326 static int msg_list_flush(int flush_it_all)
328 static int written = 0;
335 while (msg_list.head) {
336 struct msg_list_item *ml = msg_list.head;
337 int n = write(msg_fd_out, ml->buf + written, ml->len - written);
341 if (errno != EWOULDBLOCK && errno != EAGAIN)
346 FD_SET(msg_fd_out, &fds);
347 tv.tv_sec = select_timeout;
349 if (!select(msg_fd_out+1, NULL, &fds, NULL, &tv))
351 } else if ((written += n) == ml->len) {
353 msg_list.head = ml->next;
355 msg_list.tail = NULL;
363 void send_msg(enum msgcode code, char *buf, int len)
365 if (msg_fd_out < 0) {
366 io_multiplex_write(code, buf, len);
369 msg_list_add(code, buf, len);
370 msg_list_flush(NORMAL_FLUSH);
373 int get_redo_num(int itemizing, enum logcode code)
377 check_for_finished_hlinks(itemizing, code);
383 return flist_ndx_pop(&redo_list);
386 int get_hlink_num(void)
388 return flist_ndx_pop(&hlink_list);
392 * When we're the receiver and we have a local --files-from list of names
393 * that needs to be sent over the socket to the sender, we have to do two
394 * things at the same time: send the sender a list of what files we're
395 * processing and read the incoming file+info list from the sender. We do
396 * this by augmenting the read_timeout() function to copy this data. It
397 * uses the io_filesfrom_buf to read a block of data from f_in (when it is
398 * ready, since it might be a pipe) and then blast it out f_out (when it
399 * is ready to receive more data).
401 void io_set_filesfrom_fds(int f_in, int f_out)
403 io_filesfrom_f_in = f_in;
404 io_filesfrom_f_out = f_out;
405 io_filesfrom_bp = io_filesfrom_buf;
406 io_filesfrom_lastchar = '\0';
407 io_filesfrom_buflen = 0;
410 /* It's almost always an error to get an EOF when we're trying to read from the
411 * network, because the protocol is (for the most part) self-terminating.
413 * There is one case for the receiver when it is at the end of the transfer
414 * (hanging around reading any keep-alive packets that might come its way): if
415 * the sender dies before the generator's kill-signal comes through, we can end
416 * up here needing to loop until the kill-signal arrives. In this situation,
417 * kluge_around_eof will be < 0.
419 * There is another case for older protocol versions (< 24) where the module
420 * listing was not terminated, so we must ignore an EOF error in that case and
421 * exit. In this situation, kluge_around_eof will be > 0. */
422 static void whine_about_eof(int fd)
424 if (kluge_around_eof && fd == sock_f_in) {
426 if (kluge_around_eof > 0)
428 /* If we're still here after 10 seconds, exit with an error. */
429 for (i = 10*1000/20; i--; )
433 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
434 "(%.0f bytes received so far) [%s]\n",
435 (double)stats.total_read, who_am_i());
437 exit_cleanup(RERR_STREAMIO);
441 * Read from a socket with I/O timeout. return the number of bytes
442 * read. If no bytes can be read then exit, never return a number <= 0.
444 * TODO: If the remote shell connection fails, then current versions
445 * actually report an "unexpected EOF" error here. Since it's a
446 * fairly common mistake to try to use rsh when ssh is required, we
447 * should trap that: if we fail to read any data at all, we should
448 * give a better explanation. We can tell whether the connection has
449 * started by looking e.g. at whether the remote version is known yet.
451 static int read_timeout(int fd, char *buf, size_t len)
455 io_flush(NORMAL_FLUSH);
458 /* until we manage to read *something* */
468 FD_SET(msg_fd_out, &w_fds);
469 if (msg_fd_out > maxfd)
472 if (io_filesfrom_f_out >= 0) {
474 if (io_filesfrom_buflen == 0) {
475 if (io_filesfrom_f_in >= 0) {
476 FD_SET(io_filesfrom_f_in, &r_fds);
477 new_fd = io_filesfrom_f_in;
479 io_filesfrom_f_out = -1;
483 FD_SET(io_filesfrom_f_out, &w_fds);
484 new_fd = io_filesfrom_f_out;
490 tv.tv_sec = select_timeout;
495 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
499 exit_cleanup(RERR_SOCKETIO);
504 if (msg_list.head && FD_ISSET(msg_fd_out, &w_fds))
505 msg_list_flush(NORMAL_FLUSH);
507 if (io_filesfrom_f_out >= 0) {
508 if (io_filesfrom_buflen) {
509 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
510 int l = write(io_filesfrom_f_out,
512 io_filesfrom_buflen);
514 if (!(io_filesfrom_buflen -= l))
515 io_filesfrom_bp = io_filesfrom_buf;
517 io_filesfrom_bp += l;
519 /* XXX should we complain? */
520 io_filesfrom_f_out = -1;
523 } else if (io_filesfrom_f_in >= 0) {
524 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
525 int l = read(io_filesfrom_f_in,
527 sizeof io_filesfrom_buf);
529 /* Send end-of-file marker */
530 io_filesfrom_buf[0] = '\0';
531 io_filesfrom_buf[1] = '\0';
532 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
533 io_filesfrom_f_in = -1;
536 char *s = io_filesfrom_buf + l;
537 /* Transform CR and/or LF into '\0' */
538 while (s-- > io_filesfrom_buf) {
539 if (*s == '\n' || *s == '\r')
543 if (!io_filesfrom_lastchar) {
544 /* Last buf ended with a '\0', so don't
545 * let this buf start with one. */
546 while (l && !*io_filesfrom_bp)
547 io_filesfrom_bp++, l--;
550 io_filesfrom_bp = io_filesfrom_buf;
552 char *f = io_filesfrom_bp;
555 /* Eliminate any multi-'\0' runs. */
557 if (!(*t++ = *f++)) {
558 while (f != eob && !*f)
562 io_filesfrom_lastchar = f[-1];
564 io_filesfrom_buflen = l;
570 if (!FD_ISSET(fd, &r_fds))
573 n = read(fd, buf, len);
577 whine_about_eof(fd); /* Doesn't return. */
578 if (errno == EINTR || errno == EWOULDBLOCK
582 /* Don't write errors on a dead socket. */
584 close_multiplexing_out();
585 rsyserr(FERROR, errno, "read error");
586 exit_cleanup(RERR_STREAMIO);
593 if (fd == sock_f_in && io_timeout)
594 last_io_in = time(NULL);
601 * Read a line into the "fname" buffer (which must be at least MAXPATHLEN
604 int read_filesfrom_line(int fd, char *fname)
606 char ch, *s, *eob = fname + MAXPATHLEN - 1;
608 int reading_remotely = filesfrom_host != NULL;
609 int nulls = eol_nulls || reading_remotely;
614 cnt = read(fd, &ch, 1);
615 if (cnt < 0 && (errno == EWOULDBLOCK
616 || errno == EINTR || errno == EAGAIN)) {
621 tv.tv_sec = select_timeout;
623 if (!select(fd+1, &fds, NULL, NULL, &tv))
629 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
630 /* Skip empty lines if reading locally. */
631 if (!reading_remotely && s == fname)
641 if (*fname == '#' || *fname == ';')
647 static char *iobuf_out;
648 static int iobuf_out_cnt;
650 void io_start_buffering_out(void)
654 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
655 out_of_memory("io_start_buffering_out");
659 static char *iobuf_in;
660 static size_t iobuf_in_siz;
662 void io_start_buffering_in(void)
666 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
667 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
668 out_of_memory("io_start_buffering_in");
671 void io_end_buffering(void)
673 io_flush(NORMAL_FLUSH);
674 if (!io_multiplexing_out) {
680 void maybe_flush_socket(void)
682 if (iobuf_out && iobuf_out_cnt && time(NULL) - last_io_out >= 5)
683 io_flush(NORMAL_FLUSH);
686 void maybe_send_keepalive(void)
688 if (time(NULL) - last_io_out >= allowed_lull) {
689 if (!iobuf_out || !iobuf_out_cnt) {
690 if (protocol_version < 29)
691 return; /* there's nothing we can do */
692 write_int(sock_f_out, the_file_list->count);
693 write_shortint(sock_f_out, ITEM_IS_NEW);
696 io_flush(NORMAL_FLUSH);
701 * Continue trying to read len bytes - don't return until len has been
704 static void read_loop(int fd, char *buf, size_t len)
707 int n = read_timeout(fd, buf, len);
715 * Read from the file descriptor handling multiplexing - return number
718 * Never returns <= 0.
720 static int readfd_unbuffered(int fd, char *buf, size_t len)
722 static size_t remaining;
723 static size_t iobuf_in_ndx;
726 char line[BIGPATHBUFLEN];
728 if (!iobuf_in || fd != sock_f_in)
729 return read_timeout(fd, buf, len);
731 if (!io_multiplexing_in && remaining == 0) {
732 remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
738 len = MIN(len, remaining);
739 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
746 read_loop(fd, line, 4);
749 msg_bytes = tag & 0xFFFFFF;
750 tag = (tag >> 24) - MPLEX_BASE;
754 if (msg_bytes > iobuf_in_siz) {
755 if (!(iobuf_in = realloc_array(iobuf_in, char,
757 out_of_memory("readfd_unbuffered");
758 iobuf_in_siz = msg_bytes;
760 read_loop(fd, iobuf_in, msg_bytes);
761 remaining = msg_bytes;
765 if (msg_bytes >= sizeof line)
767 read_loop(fd, line, msg_bytes);
768 line[msg_bytes] = '\0';
769 /* A directory name was sent with the trailing null */
770 if (msg_bytes > 0 && !line[msg_bytes-1])
771 log_delete(line, S_IFDIR);
773 log_delete(line, S_IFREG);
776 if (msg_bytes != 4) {
777 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
778 tag, (long)msg_bytes, who_am_i());
779 exit_cleanup(RERR_STREAMIO);
781 read_loop(fd, line, msg_bytes);
782 successful_send(IVAL(line, 0));
786 if (msg_bytes >= sizeof line) {
789 "multiplexing overflow %d:%ld [%s]\n",
790 tag, (long)msg_bytes, who_am_i());
791 exit_cleanup(RERR_STREAMIO);
793 read_loop(fd, line, msg_bytes);
794 rwrite((enum logcode)tag, line, msg_bytes);
797 rprintf(FERROR, "unexpected tag %d [%s]\n",
799 exit_cleanup(RERR_STREAMIO);
804 io_flush(NORMAL_FLUSH);
810 * Do a buffered read from @p fd. Don't return until all @p n bytes
811 * have been read. If all @p n can't be read then exit with an
814 static void readfd(int fd, char *buffer, size_t N)
820 cnt = readfd_unbuffered(fd, buffer + total, N-total);
824 if (fd == write_batch_monitor_in) {
825 if ((size_t)write(batch_fd, buffer, total) != total)
826 exit_cleanup(RERR_FILEIO);
830 stats.total_read += total;
833 int read_shortint(int f)
836 readfd(f, (char *)b, 2);
837 return (b[1] << 8) + b[0];
840 int32 read_int(int f)
847 if (num == (int32)0xffffffff)
852 int64 read_longint(int f)
858 if ((int32)num != (int32)0xffffffff)
862 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
863 exit_cleanup(RERR_UNSUPPORTED);
866 num = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
872 void read_buf(int f,char *buf,size_t len)
877 void read_sbuf(int f,char *buf,size_t len)
883 uchar read_byte(int f)
886 readfd(f, (char *)&c, 1);
890 int read_vstring(int f, char *buf, int bufsize)
892 int len = read_byte(f);
895 len = (len & ~0x80) * 0x100 + read_byte(f);
897 if (len >= bufsize) {
898 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
909 /* Populate a sum_struct with values from the socket. This is
910 * called by both the sender and the receiver. */
911 void read_sum_head(int f, struct sum_struct *sum)
913 sum->count = read_int(f);
914 sum->blength = read_int(f);
915 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
916 rprintf(FERROR, "Invalid block length %ld [%s]\n",
917 (long)sum->blength, who_am_i());
918 exit_cleanup(RERR_PROTOCOL);
920 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
921 if (sum->s2length < 0 || sum->s2length > MD4_SUM_LENGTH) {
922 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
923 sum->s2length, who_am_i());
924 exit_cleanup(RERR_PROTOCOL);
926 sum->remainder = read_int(f);
927 if (sum->remainder < 0 || sum->remainder > sum->blength) {
928 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
929 (long)sum->remainder, who_am_i());
930 exit_cleanup(RERR_PROTOCOL);
934 /* Send the values from a sum_struct over the socket. Set sum to
935 * NULL if there are no checksums to send. This is called by both
936 * the generator and the sender. */
937 void write_sum_head(int f, struct sum_struct *sum)
939 static struct sum_struct null_sum;
944 write_int(f, sum->count);
945 write_int(f, sum->blength);
946 if (protocol_version >= 27)
947 write_int(f, sum->s2length);
948 write_int(f, sum->remainder);
952 * Sleep after writing to limit I/O bandwidth usage.
954 * @todo Rather than sleeping after each write, it might be better to
955 * use some kind of averaging. The current algorithm seems to always
956 * use a bit less bandwidth than specified, because it doesn't make up
957 * for slow periods. But arguably this is a feature. In addition, we
958 * ought to take the time used to write the data into account.
960 * During some phases of big transfers (file FOO is uptodate) this is
961 * called with a small bytes_written every time. As the kernel has to
962 * round small waits up to guarantee that we actually wait at least the
963 * requested number of microseconds, this can become grossly inaccurate.
964 * We therefore keep track of the bytes we've written over time and only
965 * sleep when the accumulated delay is at least 1 tenth of a second.
967 static void sleep_for_bwlimit(int bytes_written)
969 static struct timeval prior_tv;
970 static long total_written = 0;
971 struct timeval tv, start_tv;
972 long elapsed_usec, sleep_usec;
974 #define ONE_SEC 1000000L /* # of microseconds in a second */
979 total_written += bytes_written;
981 gettimeofday(&start_tv, NULL);
982 if (prior_tv.tv_sec) {
983 elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
984 + (start_tv.tv_usec - prior_tv.tv_usec);
985 total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
986 if (total_written < 0)
990 sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
991 if (sleep_usec < ONE_SEC / 10) {
996 tv.tv_sec = sleep_usec / ONE_SEC;
997 tv.tv_usec = sleep_usec % ONE_SEC;
998 select(0, NULL, NULL, NULL, &tv);
1000 gettimeofday(&prior_tv, NULL);
1001 elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
1002 + (prior_tv.tv_usec - start_tv.tv_usec);
1003 total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
1006 /* Write len bytes to the file descriptor fd, looping as necessary to get
1007 * the job done and also (in certain circumstances) reading any data on
1008 * msg_fd_in to avoid deadlock.
1010 * This function underlies the multiplexing system. The body of the
1011 * application never calls this function directly. */
1012 static void writefd_unbuffered(int fd,char *buf,size_t len)
1014 size_t n, total = 0;
1015 fd_set w_fds, r_fds;
1016 int maxfd, count, cnt, using_r_fds;
1021 while (total < len) {
1026 if (msg_fd_in >= 0 && len-total >= contiguous_write_len) {
1028 FD_SET(msg_fd_in,&r_fds);
1029 if (msg_fd_in > maxfd)
1035 tv.tv_sec = select_timeout;
1039 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1043 if (count < 0 && errno == EBADF)
1044 exit_cleanup(RERR_SOCKETIO);
1049 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1052 if (!FD_ISSET(fd, &w_fds))
1056 if (bwlimit && n > bwlimit_writemax)
1057 n = bwlimit_writemax;
1058 cnt = write(fd, buf + total, n);
1064 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1070 /* Don't try to write errors back across the stream. */
1071 if (fd == sock_f_out)
1072 close_multiplexing_out();
1073 rsyserr(FERROR, errno,
1074 "writefd_unbuffered failed to write %ld bytes: phase \"%s\" [%s]",
1075 (long)len, io_write_phase, who_am_i());
1076 /* If the other side is sending us error messages, try
1077 * to grab any messages they sent before they died. */
1078 while (fd == sock_f_out && io_multiplexing_in) {
1081 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1082 sizeof io_filesfrom_buf);
1084 exit_cleanup(RERR_STREAMIO);
1089 if (fd == sock_f_out) {
1090 if (io_timeout || am_generator)
1091 last_io_out = time(NULL);
1092 sleep_for_bwlimit(cnt);
1100 * Write an message to a multiplexed stream. If this fails then rsync
1103 static void mplex_write(enum msgcode code, char *buf, size_t len)
1105 char buffer[BIGPATHBUFLEN];
1108 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
1110 /* When the generator reads messages from the msg_fd_in pipe, it can
1111 * cause output to occur down the socket. Setting contiguous_write_len
1112 * prevents the reading of msg_fd_in once we actually start to write
1113 * this sequence of data (though we might read it before the start). */
1114 if (am_generator && msg_fd_in >= 0)
1115 contiguous_write_len = len + 4;
1117 if (n > sizeof buffer - 4)
1118 n = sizeof buffer - 4;
1120 memcpy(&buffer[4], buf, n);
1121 writefd_unbuffered(sock_f_out, buffer, n+4);
1127 writefd_unbuffered(sock_f_out, buf, len);
1129 if (am_generator && msg_fd_in >= 0)
1130 contiguous_write_len = 0;
1133 void io_flush(int flush_it_all)
1135 msg_list_flush(flush_it_all);
1137 if (!iobuf_out_cnt || no_flush)
1140 if (io_multiplexing_out)
1141 mplex_write(MSG_DATA, iobuf_out, iobuf_out_cnt);
1143 writefd_unbuffered(sock_f_out, iobuf_out, iobuf_out_cnt);
1147 static void writefd(int fd,char *buf,size_t len)
1149 if (fd == msg_fd_out) {
1150 rprintf(FERROR, "Internal error: wrong write used in receiver.\n");
1151 exit_cleanup(RERR_PROTOCOL);
1154 if (fd == sock_f_out)
1155 stats.total_written += len;
1157 if (fd == write_batch_monitor_out) {
1158 if ((size_t)write(batch_fd, buf, len) != len)
1159 exit_cleanup(RERR_FILEIO);
1162 if (!iobuf_out || fd != sock_f_out) {
1163 writefd_unbuffered(fd, buf, len);
1168 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1170 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1176 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1177 io_flush(NORMAL_FLUSH);
1181 void write_shortint(int f, int x)
1186 writefd(f, (char *)b, 2);
1189 void write_int(int f,int32 x)
1196 void write_int_named(int f, int32 x, const char *phase)
1198 io_write_phase = phase;
1200 io_write_phase = phase_unknown;
1204 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1205 * 64-bit types on this platform.
1207 void write_longint(int f, int64 x)
1211 if (x <= 0x7FFFFFFF) {
1212 write_int(f, (int)x);
1216 #if SIZEOF_INT64 < 8
1217 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1218 exit_cleanup(RERR_UNSUPPORTED);
1220 write_int(f, (int32)0xFFFFFFFF);
1221 SIVAL(b,0,(x&0xFFFFFFFF));
1222 SIVAL(b,4,((x>>32)&0xFFFFFFFF));
1228 void write_buf(int f,char *buf,size_t len)
1233 /** Write a string to the connection */
1234 void write_sbuf(int f, char *buf)
1236 writefd(f, buf, strlen(buf));
1239 void write_byte(int f, uchar c)
1241 writefd(f, (char *)&c, 1);
1244 void write_vstring(int f, char *str, int len)
1246 uchar lenbuf[3], *lb = lenbuf;
1251 "attempting to send over-long vstring (%d > %d)\n",
1253 exit_cleanup(RERR_PROTOCOL);
1255 *lb++ = len / 0x100 + 0x80;
1259 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1261 writefd(f, str, len);
1265 * Read a line of up to @p maxlen characters into @p buf (not counting
1266 * the trailing null). Strips the (required) trailing newline and all
1269 * @return 1 for success; 0 for I/O error or truncation.
1271 int read_line(int f, char *buf, size_t maxlen)
1275 read_buf(f, buf, 1);
1280 if (buf[0] != '\r') {
1289 void io_printf(int fd, const char *format, ...)
1292 char buf[BIGPATHBUFLEN];
1295 va_start(ap, format);
1296 len = vsnprintf(buf, sizeof buf, format, ap);
1300 exit_cleanup(RERR_STREAMIO);
1302 if (len > (int)sizeof buf) {
1303 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1304 exit_cleanup(RERR_STREAMIO);
1307 write_sbuf(fd, buf);
1310 /** Setup for multiplexing a MSG_* stream with the data stream. */
1311 void io_start_multiplex_out(void)
1313 io_flush(NORMAL_FLUSH);
1314 io_start_buffering_out();
1315 io_multiplexing_out = 1;
1318 /** Setup for multiplexing a MSG_* stream with the data stream. */
1319 void io_start_multiplex_in(void)
1321 io_flush(NORMAL_FLUSH);
1322 io_start_buffering_in();
1323 io_multiplexing_in = 1;
1326 /** Write an message to the multiplexed data stream. */
1327 int io_multiplex_write(enum msgcode code, char *buf, size_t len)
1329 if (!io_multiplexing_out)
1332 io_flush(NORMAL_FLUSH);
1333 stats.total_written += (len+4);
1334 mplex_write(code, buf, len);
1338 void close_multiplexing_in(void)
1340 io_multiplexing_in = 0;
1343 /** Stop output multiplexing. */
1344 void close_multiplexing_out(void)
1346 io_multiplexing_out = 0;
1349 void start_write_batch(int fd)
1351 write_stream_flags(batch_fd);
1353 /* Some communication has already taken place, but we don't
1354 * enable batch writing until here so that we can write a
1355 * canonical record of the communication even though the
1356 * actual communication so far depends on whether a daemon
1358 write_int(batch_fd, protocol_version);
1359 write_int(batch_fd, checksum_seed);
1362 write_batch_monitor_out = fd;
1364 write_batch_monitor_in = fd;
1367 void stop_write_batch(void)
1369 write_batch_monitor_out = -1;
1370 write_batch_monitor_in = -1;