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;
123 struct msg_list *next;
128 static struct msg_list *msg_list_head;
129 static struct msg_list *msg_list_tail;
131 static void flist_ndx_push(struct flist_ndx_list *lp, int ndx)
133 struct flist_ndx_item *item;
135 if (!(item = new(struct flist_ndx_item)))
136 out_of_memory("flist_ndx_push");
140 lp->tail->next = item;
146 static int flist_ndx_pop(struct flist_ndx_list *lp)
148 struct flist_ndx_item *next;
155 next = lp->head->next;
164 static void check_timeout(void)
168 if (!io_timeout || ignore_timeout)
172 last_io_in = time(NULL);
178 if (t - last_io_in >= io_timeout) {
179 if (!am_server && !am_daemon) {
180 rprintf(FERROR, "io timeout after %d seconds -- exiting\n",
181 (int)(t-last_io_in));
183 exit_cleanup(RERR_TIMEOUT);
187 /* Note the fds used for the main socket (which might really be a pipe
188 * for a local transfer, but we can ignore that). */
189 void io_set_sock_fds(int f_in, int f_out)
195 void set_io_timeout(int secs)
199 if (!io_timeout || io_timeout > SELECT_TIMEOUT)
200 select_timeout = SELECT_TIMEOUT;
202 select_timeout = io_timeout;
204 allowed_lull = read_batch ? 0 : (io_timeout + 1) / 2;
207 /* Setup the fd used to receive MSG_* messages. Only needed during the
208 * early stages of being a local sender (up through the sending of the
209 * file list) or when we're the generator (to fetch the messages from
211 void set_msg_fd_in(int fd)
216 /* Setup the fd used to send our MSG_* messages. Only needed when
217 * we're the receiver (to send our messages to the generator). */
218 void set_msg_fd_out(int fd)
221 set_nonblocking(msg_fd_out);
224 /* Add a message to the pending MSG_* list. */
225 static void msg_list_add(int code, char *buf, int len)
229 if (!(ml = new(struct msg_list)))
230 out_of_memory("msg_list_add");
232 if (!(ml->buf = new_array(char, len+4)))
233 out_of_memory("msg_list_add");
234 SIVAL(ml->buf, 0, ((code+MPLEX_BASE)<<24) | len);
235 memcpy(ml->buf+4, buf, len);
238 msg_list_tail->next = ml;
244 void send_msg(enum msgcode code, char *buf, int len)
246 if (msg_fd_out < 0) {
247 io_multiplex_write(code, buf, len);
250 msg_list_add(code, buf, len);
251 msg_list_push(NORMAL_FLUSH);
254 /* Read a message from the MSG_* fd and handle it. This is called either
255 * during the early stages of being a local sender (up through the sending
256 * of the file list) or when we're the generator (to fetch the messages
257 * from the receiver). */
258 static void read_msg_fd(void)
265 /* Temporarily disable msg_fd_in. This is needed to avoid looping back
266 * to this routine from writefd_unbuffered(). */
269 read_loop(fd, buf, 4);
272 len = tag & 0xFFFFFF;
273 tag = (tag >> 24) - MPLEX_BASE;
277 if (len != 0 || !am_generator) {
278 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
279 exit_cleanup(RERR_STREAMIO);
281 flist_ndx_push(&redo_list, -1);
284 if (len != 4 || !am_generator) {
285 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
286 exit_cleanup(RERR_STREAMIO);
288 read_loop(fd, buf, 4);
289 flist_ndx_push(&redo_list, IVAL(buf,0));
292 if (len >= (int)sizeof buf || !am_generator) {
293 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
294 exit_cleanup(RERR_STREAMIO);
296 read_loop(fd, buf, len);
297 io_multiplex_write(MSG_DELETED, buf, len);
300 if (len != 4 || !am_generator) {
301 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
302 exit_cleanup(RERR_STREAMIO);
304 read_loop(fd, buf, len);
305 if (remove_sent_files)
306 io_multiplex_write(MSG_SUCCESS, buf, len);
307 if (preserve_hard_links)
308 flist_ndx_push(&hlink_list, IVAL(buf,0));
317 read_loop(fd, buf, n);
318 rwrite((enum logcode)tag, buf, n);
323 rprintf(FERROR, "unknown message %d:%d\n", tag, len);
324 exit_cleanup(RERR_STREAMIO);
330 /* Try to push messages off the list onto the wire. If we leave with more
331 * to do, return 0. On error, return -1. If everything flushed, return 1.
332 * This is only active in the receiver. */
333 int msg_list_push(int flush_it_all)
335 static int written = 0;
342 while (msg_list_head) {
343 struct msg_list *ml = msg_list_head;
344 int n = write(msg_fd_out, ml->buf + written, ml->len - written);
348 if (errno != EWOULDBLOCK && errno != EAGAIN)
353 FD_SET(msg_fd_out, &fds);
354 tv.tv_sec = select_timeout;
356 if (!select(msg_fd_out+1, NULL, &fds, NULL, &tv))
358 } else if ((written += n) == ml->len) {
360 msg_list_head = ml->next;
362 msg_list_tail = NULL;
370 int get_redo_num(int itemizing, enum logcode code)
374 check_for_finished_hlinks(itemizing, code);
380 return flist_ndx_pop(&redo_list);
383 int get_hlink_num(void)
385 return flist_ndx_pop(&hlink_list);
389 * When we're the receiver and we have a local --files-from list of names
390 * that needs to be sent over the socket to the sender, we have to do two
391 * things at the same time: send the sender a list of what files we're
392 * processing and read the incoming file+info list from the sender. We do
393 * this by augmenting the read_timeout() function to copy this data. It
394 * uses the io_filesfrom_buf to read a block of data from f_in (when it is
395 * ready, since it might be a pipe) and then blast it out f_out (when it
396 * is ready to receive more data).
398 void io_set_filesfrom_fds(int f_in, int f_out)
400 io_filesfrom_f_in = f_in;
401 io_filesfrom_f_out = f_out;
402 io_filesfrom_bp = io_filesfrom_buf;
403 io_filesfrom_lastchar = '\0';
404 io_filesfrom_buflen = 0;
407 /* It's almost always an error to get an EOF when we're trying to read from the
408 * network, because the protocol is (for the most part) self-terminating.
410 * There is one case for the receiver when it is at the end of the transfer
411 * (hanging around reading any keep-alive packets that might come its way): if
412 * the sender dies before the generator's kill-signal comes through, we can end
413 * up here needing to loop until the kill-signal arrives. In this situation,
414 * kluge_around_eof will be < 0.
416 * There is another case for older protocol versions (< 24) where the module
417 * listing was not terminated, so we must ignore an EOF error in that case and
418 * exit. In this situation, kluge_around_eof will be > 0. */
419 static void whine_about_eof(int fd)
421 if (kluge_around_eof && fd == sock_f_in) {
423 if (kluge_around_eof > 0)
425 /* If we're still here after 10 seconds, exit with an error. */
426 for (i = 10*1000/20; i--; )
430 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
431 "(%.0f bytes received so far) [%s]\n",
432 (double)stats.total_read, who_am_i());
434 exit_cleanup(RERR_STREAMIO);
439 * Read from a socket with I/O timeout. return the number of bytes
440 * read. If no bytes can be read then exit, never return a number <= 0.
442 * TODO: If the remote shell connection fails, then current versions
443 * actually report an "unexpected EOF" error here. Since it's a
444 * fairly common mistake to try to use rsh when ssh is required, we
445 * should trap that: if we fail to read any data at all, we should
446 * give a better explanation. We can tell whether the connection has
447 * started by looking e.g. at whether the remote version is known yet.
449 static int read_timeout(int fd, char *buf, size_t len)
453 io_flush(NORMAL_FLUSH);
456 /* until we manage to read *something* */
466 FD_SET(msg_fd_out, &w_fds);
467 if (msg_fd_out > maxfd)
470 if (io_filesfrom_f_out >= 0) {
472 if (io_filesfrom_buflen == 0) {
473 if (io_filesfrom_f_in >= 0) {
474 FD_SET(io_filesfrom_f_in, &r_fds);
475 new_fd = io_filesfrom_f_in;
477 io_filesfrom_f_out = -1;
481 FD_SET(io_filesfrom_f_out, &w_fds);
482 new_fd = io_filesfrom_f_out;
488 tv.tv_sec = select_timeout;
493 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
497 exit_cleanup(RERR_SOCKETIO);
502 if (msg_list_head && FD_ISSET(msg_fd_out, &w_fds))
503 msg_list_push(NORMAL_FLUSH);
505 if (io_filesfrom_f_out >= 0) {
506 if (io_filesfrom_buflen) {
507 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
508 int l = write(io_filesfrom_f_out,
510 io_filesfrom_buflen);
512 if (!(io_filesfrom_buflen -= l))
513 io_filesfrom_bp = io_filesfrom_buf;
515 io_filesfrom_bp += l;
517 /* XXX should we complain? */
518 io_filesfrom_f_out = -1;
521 } else if (io_filesfrom_f_in >= 0) {
522 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
523 int l = read(io_filesfrom_f_in,
525 sizeof io_filesfrom_buf);
527 /* Send end-of-file marker */
528 io_filesfrom_buf[0] = '\0';
529 io_filesfrom_buf[1] = '\0';
530 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
531 io_filesfrom_f_in = -1;
534 char *s = io_filesfrom_buf + l;
535 /* Transform CR and/or LF into '\0' */
536 while (s-- > io_filesfrom_buf) {
537 if (*s == '\n' || *s == '\r')
541 if (!io_filesfrom_lastchar) {
542 /* Last buf ended with a '\0', so don't
543 * let this buf start with one. */
544 while (l && !*io_filesfrom_bp)
545 io_filesfrom_bp++, l--;
548 io_filesfrom_bp = io_filesfrom_buf;
550 char *f = io_filesfrom_bp;
553 /* Eliminate any multi-'\0' runs. */
555 if (!(*t++ = *f++)) {
556 while (f != eob && !*f)
560 io_filesfrom_lastchar = f[-1];
562 io_filesfrom_buflen = l;
568 if (!FD_ISSET(fd, &r_fds))
571 n = read(fd, buf, len);
575 whine_about_eof(fd); /* Doesn't return. */
576 if (errno == EINTR || errno == EWOULDBLOCK
580 /* Don't write errors on a dead socket. */
582 close_multiplexing_out();
583 rsyserr(FERROR, errno, "read error");
584 exit_cleanup(RERR_STREAMIO);
591 if (fd == sock_f_in && io_timeout)
592 last_io_in = time(NULL);
599 * Read a line into the "fname" buffer (which must be at least MAXPATHLEN
602 int read_filesfrom_line(int fd, char *fname)
604 char ch, *s, *eob = fname + MAXPATHLEN - 1;
606 int reading_remotely = filesfrom_host != NULL;
607 int nulls = eol_nulls || reading_remotely;
612 cnt = read(fd, &ch, 1);
613 if (cnt < 0 && (errno == EWOULDBLOCK
614 || errno == EINTR || errno == EAGAIN)) {
619 tv.tv_sec = select_timeout;
621 if (!select(fd+1, &fds, NULL, NULL, &tv))
627 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
628 /* Skip empty lines if reading locally. */
629 if (!reading_remotely && s == fname)
639 if (*fname == '#' || *fname == ';')
646 static char *iobuf_out;
647 static int iobuf_out_cnt;
649 void io_start_buffering_out(void)
653 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
654 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");
672 void io_end_buffering(void)
674 io_flush(NORMAL_FLUSH);
675 if (!io_multiplexing_out) {
682 void maybe_flush_socket(void)
684 if (iobuf_out && iobuf_out_cnt && time(NULL) - last_io_out >= 5)
685 io_flush(NORMAL_FLUSH);
689 void maybe_send_keepalive(void)
691 if (time(NULL) - last_io_out >= allowed_lull) {
692 if (!iobuf_out || !iobuf_out_cnt) {
693 if (protocol_version < 29)
694 return; /* there's nothing we can do */
695 write_int(sock_f_out, the_file_list->count);
696 write_shortint(sock_f_out, ITEM_IS_NEW);
699 io_flush(NORMAL_FLUSH);
705 * Continue trying to read len bytes - don't return until len has been
708 static void read_loop(int fd, char *buf, size_t len)
711 int n = read_timeout(fd, buf, len);
720 * Read from the file descriptor handling multiplexing - return number
723 * Never returns <= 0.
725 static int readfd_unbuffered(int fd, char *buf, size_t len)
727 static size_t remaining;
728 static size_t iobuf_in_ndx;
731 char line[BIGPATHBUFLEN];
733 if (!iobuf_in || fd != sock_f_in)
734 return read_timeout(fd, buf, len);
736 if (!io_multiplexing_in && remaining == 0) {
737 remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
743 len = MIN(len, remaining);
744 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
751 read_loop(fd, line, 4);
754 msg_bytes = tag & 0xFFFFFF;
755 tag = (tag >> 24) - MPLEX_BASE;
759 if (msg_bytes > iobuf_in_siz) {
760 if (!(iobuf_in = realloc_array(iobuf_in, char,
762 out_of_memory("readfd_unbuffered");
763 iobuf_in_siz = msg_bytes;
765 read_loop(fd, iobuf_in, msg_bytes);
766 remaining = msg_bytes;
770 if (msg_bytes >= sizeof line)
772 read_loop(fd, line, msg_bytes);
773 line[msg_bytes] = '\0';
774 /* A directory name was sent with the trailing null */
775 if (msg_bytes > 0 && !line[msg_bytes-1])
776 log_delete(line, S_IFDIR);
778 log_delete(line, S_IFREG);
781 if (msg_bytes != 4) {
782 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
783 tag, (long)msg_bytes, who_am_i());
784 exit_cleanup(RERR_STREAMIO);
786 read_loop(fd, line, msg_bytes);
787 successful_send(IVAL(line, 0));
791 if (msg_bytes >= sizeof line) {
794 "multiplexing overflow %d:%ld [%s]\n",
795 tag, (long)msg_bytes, who_am_i());
796 exit_cleanup(RERR_STREAMIO);
798 read_loop(fd, line, msg_bytes);
799 rwrite((enum logcode)tag, line, msg_bytes);
802 rprintf(FERROR, "unexpected tag %d [%s]\n",
804 exit_cleanup(RERR_STREAMIO);
809 io_flush(NORMAL_FLUSH);
817 * Do a buffered read from @p fd. Don't return until all @p n bytes
818 * have been read. If all @p n can't be read then exit with an
821 static void readfd(int fd, char *buffer, size_t N)
827 ret = readfd_unbuffered(fd, buffer + total, N-total);
831 if (fd == write_batch_monitor_in) {
832 if ((size_t)write(batch_fd, buffer, total) != total)
833 exit_cleanup(RERR_FILEIO);
837 stats.total_read += total;
841 int read_shortint(int f)
844 readfd(f, (char *)b, 2);
845 return (b[1] << 8) + b[0];
849 int32 read_int(int f)
856 if (ret == (int32)0xffffffff)
861 int64 read_longint(int f)
867 if ((int32)ret != (int32)0xffffffff)
871 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
872 exit_cleanup(RERR_UNSUPPORTED);
875 ret = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
881 void read_buf(int f,char *buf,size_t len)
886 void read_sbuf(int f,char *buf,size_t len)
892 uchar read_byte(int f)
895 readfd(f, (char *)&c, 1);
899 int read_vstring(int f, char *buf, int bufsize)
901 int len = read_byte(f);
904 len = (len & ~0x80) * 0x100 + read_byte(f);
906 if (len >= bufsize) {
907 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
918 /* Populate a sum_struct with values from the socket. This is
919 * called by both the sender and the receiver. */
920 void read_sum_head(int f, struct sum_struct *sum)
922 sum->count = read_int(f);
923 sum->blength = read_int(f);
924 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
925 rprintf(FERROR, "Invalid block length %ld [%s]\n",
926 (long)sum->blength, who_am_i());
927 exit_cleanup(RERR_PROTOCOL);
929 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
930 if (sum->s2length < 0 || sum->s2length > MD4_SUM_LENGTH) {
931 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
932 sum->s2length, who_am_i());
933 exit_cleanup(RERR_PROTOCOL);
935 sum->remainder = read_int(f);
936 if (sum->remainder < 0 || sum->remainder > sum->blength) {
937 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
938 (long)sum->remainder, who_am_i());
939 exit_cleanup(RERR_PROTOCOL);
943 /* Send the values from a sum_struct over the socket. Set sum to
944 * NULL if there are no checksums to send. This is called by both
945 * the generator and the sender. */
946 void write_sum_head(int f, struct sum_struct *sum)
948 static struct sum_struct null_sum;
953 write_int(f, sum->count);
954 write_int(f, sum->blength);
955 if (protocol_version >= 27)
956 write_int(f, sum->s2length);
957 write_int(f, sum->remainder);
962 * Sleep after writing to limit I/O bandwidth usage.
964 * @todo Rather than sleeping after each write, it might be better to
965 * use some kind of averaging. The current algorithm seems to always
966 * use a bit less bandwidth than specified, because it doesn't make up
967 * for slow periods. But arguably this is a feature. In addition, we
968 * ought to take the time used to write the data into account.
970 * During some phases of big transfers (file FOO is uptodate) this is
971 * called with a small bytes_written every time. As the kernel has to
972 * round small waits up to guarantee that we actually wait at least the
973 * requested number of microseconds, this can become grossly inaccurate.
974 * We therefore keep track of the bytes we've written over time and only
975 * sleep when the accumulated delay is at least 1 tenth of a second.
977 static void sleep_for_bwlimit(int bytes_written)
979 static struct timeval prior_tv;
980 static long total_written = 0;
981 struct timeval tv, start_tv;
982 long elapsed_usec, sleep_usec;
984 #define ONE_SEC 1000000L /* # of microseconds in a second */
989 total_written += bytes_written;
991 gettimeofday(&start_tv, NULL);
992 if (prior_tv.tv_sec) {
993 elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
994 + (start_tv.tv_usec - prior_tv.tv_usec);
995 total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
996 if (total_written < 0)
1000 sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
1001 if (sleep_usec < ONE_SEC / 10) {
1002 prior_tv = start_tv;
1006 tv.tv_sec = sleep_usec / ONE_SEC;
1007 tv.tv_usec = sleep_usec % ONE_SEC;
1008 select(0, NULL, NULL, NULL, &tv);
1010 gettimeofday(&prior_tv, NULL);
1011 elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
1012 + (prior_tv.tv_usec - start_tv.tv_usec);
1013 total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
1017 /* Write len bytes to the file descriptor fd, looping as necessary to get
1018 * the job done and also (in certain circumstnces) reading any data on
1019 * msg_fd_in to avoid deadlock.
1021 * This function underlies the multiplexing system. The body of the
1022 * application never calls this function directly. */
1023 static void writefd_unbuffered(int fd,char *buf,size_t len)
1025 size_t n, total = 0;
1026 fd_set w_fds, r_fds;
1027 int maxfd, count, ret, using_r_fds;
1032 while (total < len) {
1037 if (msg_fd_in >= 0 && len-total >= contiguous_write_len) {
1039 FD_SET(msg_fd_in,&r_fds);
1040 if (msg_fd_in > maxfd)
1046 tv.tv_sec = select_timeout;
1050 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1054 if (count < 0 && errno == EBADF)
1055 exit_cleanup(RERR_SOCKETIO);
1060 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1063 if (!FD_ISSET(fd, &w_fds))
1067 if (bwlimit && n > bwlimit_writemax)
1068 n = bwlimit_writemax;
1069 ret = write(fd, buf + total, n);
1075 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1081 /* Don't try to write errors back across the stream. */
1082 if (fd == sock_f_out)
1083 close_multiplexing_out();
1084 rsyserr(FERROR, errno,
1085 "writefd_unbuffered failed to write %ld bytes: phase \"%s\" [%s]",
1086 (long)len, io_write_phase, who_am_i());
1087 /* If the other side is sending us error messages, try
1088 * to grab any messages they sent before they died. */
1089 while (fd == sock_f_out && io_multiplexing_in) {
1092 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1093 sizeof io_filesfrom_buf);
1095 exit_cleanup(RERR_STREAMIO);
1100 if (fd == sock_f_out) {
1101 if (io_timeout || am_generator)
1102 last_io_out = time(NULL);
1103 sleep_for_bwlimit(ret);
1112 * Write an message to a multiplexed stream. If this fails then rsync
1115 static void mplex_write(enum msgcode code, char *buf, size_t len)
1117 char buffer[BIGPATHBUFLEN];
1120 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
1122 /* When the generator reads messages from the msg_fd_in pipe, it can
1123 * cause output to occur down the socket. Setting contiguous_write_len
1124 * prevents the reading of msg_fd_in once we actually start to write
1125 * this sequence of data (though we might read it before the start). */
1126 if (am_generator && msg_fd_in >= 0)
1127 contiguous_write_len = len + 4;
1129 if (n > sizeof buffer - 4)
1130 n = sizeof buffer - 4;
1132 memcpy(&buffer[4], buf, n);
1133 writefd_unbuffered(sock_f_out, buffer, n+4);
1139 writefd_unbuffered(sock_f_out, buf, len);
1141 if (am_generator && msg_fd_in >= 0)
1142 contiguous_write_len = 0;
1146 void io_flush(int flush_it_all)
1148 msg_list_push(flush_it_all);
1150 if (!iobuf_out_cnt || no_flush)
1153 if (io_multiplexing_out)
1154 mplex_write(MSG_DATA, iobuf_out, iobuf_out_cnt);
1156 writefd_unbuffered(sock_f_out, iobuf_out, iobuf_out_cnt);
1161 static void writefd(int fd,char *buf,size_t len)
1163 if (fd == msg_fd_out) {
1164 rprintf(FERROR, "Internal error: wrong write used in receiver.\n");
1165 exit_cleanup(RERR_PROTOCOL);
1168 if (fd == sock_f_out)
1169 stats.total_written += len;
1171 if (fd == write_batch_monitor_out) {
1172 if ((size_t)write(batch_fd, buf, len) != len)
1173 exit_cleanup(RERR_FILEIO);
1176 if (!iobuf_out || fd != sock_f_out) {
1177 writefd_unbuffered(fd, buf, len);
1182 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1184 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1190 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1191 io_flush(NORMAL_FLUSH);
1196 void write_shortint(int f, int x)
1201 writefd(f, (char *)b, 2);
1205 void write_int(int f,int32 x)
1213 void write_int_named(int f, int32 x, const char *phase)
1215 io_write_phase = phase;
1217 io_write_phase = phase_unknown;
1222 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1223 * 64-bit types on this platform.
1225 void write_longint(int f, int64 x)
1229 if (x <= 0x7FFFFFFF) {
1230 write_int(f, (int)x);
1234 #if SIZEOF_INT64 < 8
1235 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1236 exit_cleanup(RERR_UNSUPPORTED);
1238 write_int(f, (int32)0xFFFFFFFF);
1239 SIVAL(b,0,(x&0xFFFFFFFF));
1240 SIVAL(b,4,((x>>32)&0xFFFFFFFF));
1246 void write_buf(int f,char *buf,size_t len)
1251 /** Write a string to the connection */
1252 void write_sbuf(int f, char *buf)
1254 writefd(f, buf, strlen(buf));
1257 void write_byte(int f, uchar c)
1259 writefd(f, (char *)&c, 1);
1262 void write_vstring(int f, char *str, int len)
1264 uchar lenbuf[3], *lb = lenbuf;
1269 "attempting to send over-long vstring (%d > %d)\n",
1271 exit_cleanup(RERR_PROTOCOL);
1273 *lb++ = len / 0x100 + 0x80;
1277 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1279 writefd(f, str, len);
1284 * Read a line of up to @p maxlen characters into @p buf (not counting
1285 * the trailing null). Strips the (required) trailing newline and all
1288 * @return 1 for success; 0 for I/O error or truncation.
1290 int read_line(int f, char *buf, size_t maxlen)
1294 read_buf(f, buf, 1);
1299 if (buf[0] != '\r') {
1309 void io_printf(int fd, const char *format, ...)
1312 char buf[BIGPATHBUFLEN];
1315 va_start(ap, format);
1316 len = vsnprintf(buf, sizeof buf, format, ap);
1320 exit_cleanup(RERR_STREAMIO);
1322 if (len > (int)sizeof buf) {
1323 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1324 exit_cleanup(RERR_STREAMIO);
1327 write_sbuf(fd, buf);
1331 /** Setup for multiplexing a MSG_* stream with the data stream. */
1332 void io_start_multiplex_out(void)
1334 io_flush(NORMAL_FLUSH);
1335 io_start_buffering_out();
1336 io_multiplexing_out = 1;
1339 /** Setup for multiplexing a MSG_* stream with the data stream. */
1340 void io_start_multiplex_in(void)
1342 io_flush(NORMAL_FLUSH);
1343 io_start_buffering_in();
1344 io_multiplexing_in = 1;
1347 /** Write an message to the multiplexed data stream. */
1348 int io_multiplex_write(enum msgcode code, char *buf, size_t len)
1350 if (!io_multiplexing_out)
1353 io_flush(NORMAL_FLUSH);
1354 stats.total_written += (len+4);
1355 mplex_write(code, buf, len);
1359 void close_multiplexing_in(void)
1361 io_multiplexing_in = 0;
1364 /** Stop output multiplexing. */
1365 void close_multiplexing_out(void)
1367 io_multiplexing_out = 0;
1370 void start_write_batch(int fd)
1372 write_stream_flags(batch_fd);
1374 /* Some communication has already taken place, but we don't
1375 * enable batch writing until here so that we can write a
1376 * canonical record of the communication even though the
1377 * actual communication so far depends on whether a daemon
1379 write_int(batch_fd, protocol_version);
1380 write_int(batch_fd, checksum_seed);
1383 write_batch_monitor_out = fd;
1385 write_batch_monitor_in = fd;
1388 void stop_write_batch(void)
1390 write_batch_monitor_out = -1;
1391 write_batch_monitor_in = -1;