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);
442 * Read from a socket with I/O timeout. return the number of bytes
443 * read. If no bytes can be read then exit, never return a number <= 0.
445 * TODO: If the remote shell connection fails, then current versions
446 * actually report an "unexpected EOF" error here. Since it's a
447 * fairly common mistake to try to use rsh when ssh is required, we
448 * should trap that: if we fail to read any data at all, we should
449 * give a better explanation. We can tell whether the connection has
450 * started by looking e.g. at whether the remote version is known yet.
452 static int read_timeout(int fd, char *buf, size_t len)
456 io_flush(NORMAL_FLUSH);
459 /* until we manage to read *something* */
469 FD_SET(msg_fd_out, &w_fds);
470 if (msg_fd_out > maxfd)
473 if (io_filesfrom_f_out >= 0) {
475 if (io_filesfrom_buflen == 0) {
476 if (io_filesfrom_f_in >= 0) {
477 FD_SET(io_filesfrom_f_in, &r_fds);
478 new_fd = io_filesfrom_f_in;
480 io_filesfrom_f_out = -1;
484 FD_SET(io_filesfrom_f_out, &w_fds);
485 new_fd = io_filesfrom_f_out;
491 tv.tv_sec = select_timeout;
496 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
500 exit_cleanup(RERR_SOCKETIO);
505 if (msg_list.head && FD_ISSET(msg_fd_out, &w_fds))
506 msg_list_flush(NORMAL_FLUSH);
508 if (io_filesfrom_f_out >= 0) {
509 if (io_filesfrom_buflen) {
510 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
511 int l = write(io_filesfrom_f_out,
513 io_filesfrom_buflen);
515 if (!(io_filesfrom_buflen -= l))
516 io_filesfrom_bp = io_filesfrom_buf;
518 io_filesfrom_bp += l;
520 /* XXX should we complain? */
521 io_filesfrom_f_out = -1;
524 } else if (io_filesfrom_f_in >= 0) {
525 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
526 int l = read(io_filesfrom_f_in,
528 sizeof io_filesfrom_buf);
530 /* Send end-of-file marker */
531 io_filesfrom_buf[0] = '\0';
532 io_filesfrom_buf[1] = '\0';
533 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
534 io_filesfrom_f_in = -1;
537 char *s = io_filesfrom_buf + l;
538 /* Transform CR and/or LF into '\0' */
539 while (s-- > io_filesfrom_buf) {
540 if (*s == '\n' || *s == '\r')
544 if (!io_filesfrom_lastchar) {
545 /* Last buf ended with a '\0', so don't
546 * let this buf start with one. */
547 while (l && !*io_filesfrom_bp)
548 io_filesfrom_bp++, l--;
551 io_filesfrom_bp = io_filesfrom_buf;
553 char *f = io_filesfrom_bp;
556 /* Eliminate any multi-'\0' runs. */
558 if (!(*t++ = *f++)) {
559 while (f != eob && !*f)
563 io_filesfrom_lastchar = f[-1];
565 io_filesfrom_buflen = l;
571 if (!FD_ISSET(fd, &r_fds))
574 n = read(fd, buf, len);
578 whine_about_eof(fd); /* Doesn't return. */
579 if (errno == EINTR || errno == EWOULDBLOCK
583 /* Don't write errors on a dead socket. */
585 close_multiplexing_out();
586 rsyserr(FERROR, errno, "read error");
587 exit_cleanup(RERR_STREAMIO);
594 if (fd == sock_f_in && io_timeout)
595 last_io_in = time(NULL);
602 * Read a line into the "fname" buffer (which must be at least MAXPATHLEN
605 int read_filesfrom_line(int fd, char *fname)
607 char ch, *s, *eob = fname + MAXPATHLEN - 1;
609 int reading_remotely = filesfrom_host != NULL;
610 int nulls = eol_nulls || reading_remotely;
615 cnt = read(fd, &ch, 1);
616 if (cnt < 0 && (errno == EWOULDBLOCK
617 || errno == EINTR || errno == EAGAIN)) {
622 tv.tv_sec = select_timeout;
624 if (!select(fd+1, &fds, NULL, NULL, &tv))
630 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
631 /* Skip empty lines if reading locally. */
632 if (!reading_remotely && s == fname)
642 if (*fname == '#' || *fname == ';')
649 static char *iobuf_out;
650 static int iobuf_out_cnt;
652 void io_start_buffering_out(void)
656 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
657 out_of_memory("io_start_buffering_out");
662 static char *iobuf_in;
663 static size_t iobuf_in_siz;
665 void io_start_buffering_in(void)
669 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
670 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
671 out_of_memory("io_start_buffering_in");
675 void io_end_buffering(void)
677 io_flush(NORMAL_FLUSH);
678 if (!io_multiplexing_out) {
685 void maybe_flush_socket(void)
687 if (iobuf_out && iobuf_out_cnt && time(NULL) - last_io_out >= 5)
688 io_flush(NORMAL_FLUSH);
692 void maybe_send_keepalive(void)
694 if (time(NULL) - last_io_out >= allowed_lull) {
695 if (!iobuf_out || !iobuf_out_cnt) {
696 if (protocol_version < 29)
697 return; /* there's nothing we can do */
698 write_int(sock_f_out, the_file_list->count);
699 write_shortint(sock_f_out, ITEM_IS_NEW);
702 io_flush(NORMAL_FLUSH);
708 * Continue trying to read len bytes - don't return until len has been
711 static void read_loop(int fd, char *buf, size_t len)
714 int n = read_timeout(fd, buf, len);
723 * Read from the file descriptor handling multiplexing - return number
726 * Never returns <= 0.
728 static int readfd_unbuffered(int fd, char *buf, size_t len)
730 static size_t remaining;
731 static size_t iobuf_in_ndx;
734 char line[BIGPATHBUFLEN];
736 if (!iobuf_in || fd != sock_f_in)
737 return read_timeout(fd, buf, len);
739 if (!io_multiplexing_in && remaining == 0) {
740 remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
746 len = MIN(len, remaining);
747 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
754 read_loop(fd, line, 4);
757 msg_bytes = tag & 0xFFFFFF;
758 tag = (tag >> 24) - MPLEX_BASE;
762 if (msg_bytes > iobuf_in_siz) {
763 if (!(iobuf_in = realloc_array(iobuf_in, char,
765 out_of_memory("readfd_unbuffered");
766 iobuf_in_siz = msg_bytes;
768 read_loop(fd, iobuf_in, msg_bytes);
769 remaining = msg_bytes;
773 if (msg_bytes >= sizeof line)
775 read_loop(fd, line, msg_bytes);
776 line[msg_bytes] = '\0';
777 /* A directory name was sent with the trailing null */
778 if (msg_bytes > 0 && !line[msg_bytes-1])
779 log_delete(line, S_IFDIR);
781 log_delete(line, S_IFREG);
784 if (msg_bytes != 4) {
785 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
786 tag, (long)msg_bytes, who_am_i());
787 exit_cleanup(RERR_STREAMIO);
789 read_loop(fd, line, msg_bytes);
790 successful_send(IVAL(line, 0));
794 if (msg_bytes >= sizeof line) {
797 "multiplexing overflow %d:%ld [%s]\n",
798 tag, (long)msg_bytes, who_am_i());
799 exit_cleanup(RERR_STREAMIO);
801 read_loop(fd, line, msg_bytes);
802 rwrite((enum logcode)tag, line, msg_bytes);
805 rprintf(FERROR, "unexpected tag %d [%s]\n",
807 exit_cleanup(RERR_STREAMIO);
812 io_flush(NORMAL_FLUSH);
820 * Do a buffered read from @p fd. Don't return until all @p n bytes
821 * have been read. If all @p n can't be read then exit with an
824 static void readfd(int fd, char *buffer, size_t N)
830 ret = readfd_unbuffered(fd, buffer + total, N-total);
834 if (fd == write_batch_monitor_in) {
835 if ((size_t)write(batch_fd, buffer, total) != total)
836 exit_cleanup(RERR_FILEIO);
840 stats.total_read += total;
844 int read_shortint(int f)
847 readfd(f, (char *)b, 2);
848 return (b[1] << 8) + b[0];
852 int32 read_int(int f)
859 if (ret == (int32)0xffffffff)
864 int64 read_longint(int f)
870 if ((int32)ret != (int32)0xffffffff)
874 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
875 exit_cleanup(RERR_UNSUPPORTED);
878 ret = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
884 void read_buf(int f,char *buf,size_t len)
889 void read_sbuf(int f,char *buf,size_t len)
895 uchar read_byte(int f)
898 readfd(f, (char *)&c, 1);
902 int read_vstring(int f, char *buf, int bufsize)
904 int len = read_byte(f);
907 len = (len & ~0x80) * 0x100 + read_byte(f);
909 if (len >= bufsize) {
910 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
921 /* Populate a sum_struct with values from the socket. This is
922 * called by both the sender and the receiver. */
923 void read_sum_head(int f, struct sum_struct *sum)
925 sum->count = read_int(f);
926 sum->blength = read_int(f);
927 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
928 rprintf(FERROR, "Invalid block length %ld [%s]\n",
929 (long)sum->blength, who_am_i());
930 exit_cleanup(RERR_PROTOCOL);
932 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
933 if (sum->s2length < 0 || sum->s2length > MD4_SUM_LENGTH) {
934 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
935 sum->s2length, who_am_i());
936 exit_cleanup(RERR_PROTOCOL);
938 sum->remainder = read_int(f);
939 if (sum->remainder < 0 || sum->remainder > sum->blength) {
940 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
941 (long)sum->remainder, who_am_i());
942 exit_cleanup(RERR_PROTOCOL);
946 /* Send the values from a sum_struct over the socket. Set sum to
947 * NULL if there are no checksums to send. This is called by both
948 * the generator and the sender. */
949 void write_sum_head(int f, struct sum_struct *sum)
951 static struct sum_struct null_sum;
956 write_int(f, sum->count);
957 write_int(f, sum->blength);
958 if (protocol_version >= 27)
959 write_int(f, sum->s2length);
960 write_int(f, sum->remainder);
965 * Sleep after writing to limit I/O bandwidth usage.
967 * @todo Rather than sleeping after each write, it might be better to
968 * use some kind of averaging. The current algorithm seems to always
969 * use a bit less bandwidth than specified, because it doesn't make up
970 * for slow periods. But arguably this is a feature. In addition, we
971 * ought to take the time used to write the data into account.
973 * During some phases of big transfers (file FOO is uptodate) this is
974 * called with a small bytes_written every time. As the kernel has to
975 * round small waits up to guarantee that we actually wait at least the
976 * requested number of microseconds, this can become grossly inaccurate.
977 * We therefore keep track of the bytes we've written over time and only
978 * sleep when the accumulated delay is at least 1 tenth of a second.
980 static void sleep_for_bwlimit(int bytes_written)
982 static struct timeval prior_tv;
983 static long total_written = 0;
984 struct timeval tv, start_tv;
985 long elapsed_usec, sleep_usec;
987 #define ONE_SEC 1000000L /* # of microseconds in a second */
992 total_written += bytes_written;
994 gettimeofday(&start_tv, NULL);
995 if (prior_tv.tv_sec) {
996 elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
997 + (start_tv.tv_usec - prior_tv.tv_usec);
998 total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
999 if (total_written < 0)
1003 sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
1004 if (sleep_usec < ONE_SEC / 10) {
1005 prior_tv = start_tv;
1009 tv.tv_sec = sleep_usec / ONE_SEC;
1010 tv.tv_usec = sleep_usec % ONE_SEC;
1011 select(0, NULL, NULL, NULL, &tv);
1013 gettimeofday(&prior_tv, NULL);
1014 elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
1015 + (prior_tv.tv_usec - start_tv.tv_usec);
1016 total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
1020 /* Write len bytes to the file descriptor fd, looping as necessary to get
1021 * the job done and also (in certain circumstances) reading any data on
1022 * msg_fd_in to avoid deadlock.
1024 * This function underlies the multiplexing system. The body of the
1025 * application never calls this function directly. */
1026 static void writefd_unbuffered(int fd,char *buf,size_t len)
1028 size_t n, total = 0;
1029 fd_set w_fds, r_fds;
1030 int maxfd, count, ret, using_r_fds;
1035 while (total < len) {
1040 if (msg_fd_in >= 0 && len-total >= contiguous_write_len) {
1042 FD_SET(msg_fd_in,&r_fds);
1043 if (msg_fd_in > maxfd)
1049 tv.tv_sec = select_timeout;
1053 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1057 if (count < 0 && errno == EBADF)
1058 exit_cleanup(RERR_SOCKETIO);
1063 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1066 if (!FD_ISSET(fd, &w_fds))
1070 if (bwlimit && n > bwlimit_writemax)
1071 n = bwlimit_writemax;
1072 ret = write(fd, buf + total, n);
1078 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1084 /* Don't try to write errors back across the stream. */
1085 if (fd == sock_f_out)
1086 close_multiplexing_out();
1087 rsyserr(FERROR, errno,
1088 "writefd_unbuffered failed to write %ld bytes: phase \"%s\" [%s]",
1089 (long)len, io_write_phase, who_am_i());
1090 /* If the other side is sending us error messages, try
1091 * to grab any messages they sent before they died. */
1092 while (fd == sock_f_out && io_multiplexing_in) {
1095 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1096 sizeof io_filesfrom_buf);
1098 exit_cleanup(RERR_STREAMIO);
1103 if (fd == sock_f_out) {
1104 if (io_timeout || am_generator)
1105 last_io_out = time(NULL);
1106 sleep_for_bwlimit(ret);
1115 * Write an message to a multiplexed stream. If this fails then rsync
1118 static void mplex_write(enum msgcode code, char *buf, size_t len)
1120 char buffer[BIGPATHBUFLEN];
1123 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
1125 /* When the generator reads messages from the msg_fd_in pipe, it can
1126 * cause output to occur down the socket. Setting contiguous_write_len
1127 * prevents the reading of msg_fd_in once we actually start to write
1128 * this sequence of data (though we might read it before the start). */
1129 if (am_generator && msg_fd_in >= 0)
1130 contiguous_write_len = len + 4;
1132 if (n > sizeof buffer - 4)
1133 n = sizeof buffer - 4;
1135 memcpy(&buffer[4], buf, n);
1136 writefd_unbuffered(sock_f_out, buffer, n+4);
1142 writefd_unbuffered(sock_f_out, buf, len);
1144 if (am_generator && msg_fd_in >= 0)
1145 contiguous_write_len = 0;
1149 void io_flush(int flush_it_all)
1151 msg_list_flush(flush_it_all);
1153 if (!iobuf_out_cnt || no_flush)
1156 if (io_multiplexing_out)
1157 mplex_write(MSG_DATA, iobuf_out, iobuf_out_cnt);
1159 writefd_unbuffered(sock_f_out, iobuf_out, iobuf_out_cnt);
1164 static void writefd(int fd,char *buf,size_t len)
1166 if (fd == msg_fd_out) {
1167 rprintf(FERROR, "Internal error: wrong write used in receiver.\n");
1168 exit_cleanup(RERR_PROTOCOL);
1171 if (fd == sock_f_out)
1172 stats.total_written += len;
1174 if (fd == write_batch_monitor_out) {
1175 if ((size_t)write(batch_fd, buf, len) != len)
1176 exit_cleanup(RERR_FILEIO);
1179 if (!iobuf_out || fd != sock_f_out) {
1180 writefd_unbuffered(fd, buf, len);
1185 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1187 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1193 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1194 io_flush(NORMAL_FLUSH);
1199 void write_shortint(int f, int x)
1204 writefd(f, (char *)b, 2);
1208 void write_int(int f,int32 x)
1216 void write_int_named(int f, int32 x, const char *phase)
1218 io_write_phase = phase;
1220 io_write_phase = phase_unknown;
1225 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1226 * 64-bit types on this platform.
1228 void write_longint(int f, int64 x)
1232 if (x <= 0x7FFFFFFF) {
1233 write_int(f, (int)x);
1237 #if SIZEOF_INT64 < 8
1238 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1239 exit_cleanup(RERR_UNSUPPORTED);
1241 write_int(f, (int32)0xFFFFFFFF);
1242 SIVAL(b,0,(x&0xFFFFFFFF));
1243 SIVAL(b,4,((x>>32)&0xFFFFFFFF));
1249 void write_buf(int f,char *buf,size_t len)
1254 /** Write a string to the connection */
1255 void write_sbuf(int f, char *buf)
1257 writefd(f, buf, strlen(buf));
1260 void write_byte(int f, uchar c)
1262 writefd(f, (char *)&c, 1);
1265 void write_vstring(int f, char *str, int len)
1267 uchar lenbuf[3], *lb = lenbuf;
1272 "attempting to send over-long vstring (%d > %d)\n",
1274 exit_cleanup(RERR_PROTOCOL);
1276 *lb++ = len / 0x100 + 0x80;
1280 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1282 writefd(f, str, len);
1287 * Read a line of up to @p maxlen characters into @p buf (not counting
1288 * the trailing null). Strips the (required) trailing newline and all
1291 * @return 1 for success; 0 for I/O error or truncation.
1293 int read_line(int f, char *buf, size_t maxlen)
1297 read_buf(f, buf, 1);
1302 if (buf[0] != '\r') {
1312 void io_printf(int fd, const char *format, ...)
1315 char buf[BIGPATHBUFLEN];
1318 va_start(ap, format);
1319 len = vsnprintf(buf, sizeof buf, format, ap);
1323 exit_cleanup(RERR_STREAMIO);
1325 if (len > (int)sizeof buf) {
1326 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1327 exit_cleanup(RERR_STREAMIO);
1330 write_sbuf(fd, buf);
1334 /** Setup for multiplexing a MSG_* stream with the data stream. */
1335 void io_start_multiplex_out(void)
1337 io_flush(NORMAL_FLUSH);
1338 io_start_buffering_out();
1339 io_multiplexing_out = 1;
1342 /** Setup for multiplexing a MSG_* stream with the data stream. */
1343 void io_start_multiplex_in(void)
1345 io_flush(NORMAL_FLUSH);
1346 io_start_buffering_in();
1347 io_multiplexing_in = 1;
1350 /** Write an message to the multiplexed data stream. */
1351 int io_multiplex_write(enum msgcode code, char *buf, size_t len)
1353 if (!io_multiplexing_out)
1356 io_flush(NORMAL_FLUSH);
1357 stats.total_written += (len+4);
1358 mplex_write(code, buf, len);
1362 void close_multiplexing_in(void)
1364 io_multiplexing_in = 0;
1367 /** Stop output multiplexing. */
1368 void close_multiplexing_out(void)
1370 io_multiplexing_out = 0;
1373 void start_write_batch(int fd)
1375 write_stream_flags(batch_fd);
1377 /* Some communication has already taken place, but we don't
1378 * enable batch writing until here so that we can write a
1379 * canonical record of the communication even though the
1380 * actual communication so far depends on whether a daemon
1382 write_int(batch_fd, protocol_version);
1383 write_int(batch_fd, checksum_seed);
1386 write_batch_monitor_out = fd;
1388 write_batch_monitor_in = fd;
1391 void stop_write_batch(void)
1393 write_batch_monitor_out = -1;
1394 write_batch_monitor_in = -1;