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 csum_length;
53 extern int checksum_seed;
54 extern int protocol_version;
55 extern int remove_sent_files;
56 extern int preserve_hard_links;
57 extern char *filesfrom_host;
58 extern struct stats stats;
59 extern struct file_list *the_file_list;
61 const char phase_unknown[] = "unknown";
62 int select_timeout = SELECT_TIMEOUT;
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;
96 static int write_batch_monitor_in = -1;
97 static int write_batch_monitor_out = -1;
99 static int io_filesfrom_f_in = -1;
100 static int io_filesfrom_f_out = -1;
101 static char io_filesfrom_buf[2048];
102 static char *io_filesfrom_bp;
103 static char io_filesfrom_lastchar;
104 static int io_filesfrom_buflen;
105 static size_t contiguous_write_len = 0;
107 static void read_loop(int fd, char *buf, size_t len);
109 struct flist_ndx_item {
110 struct flist_ndx_item *next;
114 struct flist_ndx_list {
115 struct flist_ndx_item *head, *tail;
118 static struct flist_ndx_list redo_list, hlink_list;
121 struct msg_list *next;
126 static struct msg_list *msg_list_head;
127 static struct msg_list *msg_list_tail;
129 static void flist_ndx_push(struct flist_ndx_list *lp, int ndx)
131 struct flist_ndx_item *item;
133 if (!(item = new(struct flist_ndx_item)))
134 out_of_memory("flist_ndx_push");
138 lp->tail->next = item;
144 static int flist_ndx_pop(struct flist_ndx_list *lp)
146 struct flist_ndx_item *next;
153 next = lp->head->next;
162 static void check_timeout(void)
166 if (!io_timeout || ignore_timeout)
170 last_io = time(NULL);
176 if (t - last_io >= io_timeout) {
177 if (!am_server && !am_daemon) {
178 rprintf(FERROR, "io timeout after %d seconds -- exiting\n",
181 exit_cleanup(RERR_TIMEOUT);
185 /* Note the fds used for the main socket (which might really be a pipe
186 * for a local transfer, but we can ignore that). */
187 void io_set_sock_fds(int f_in, int f_out)
193 /* Setup the fd used to receive MSG_* messages. Only needed during the
194 * early stages of being a local sender (up through the sending of the
195 * file list) or when we're the generator (to fetch the messages from
197 void set_msg_fd_in(int fd)
202 /* Setup the fd used to send our MSG_* messages. Only needed when
203 * we're the receiver (to send our messages to the generator). */
204 void set_msg_fd_out(int fd)
207 set_nonblocking(msg_fd_out);
210 /* Add a message to the pending MSG_* list. */
211 static void msg_list_add(int code, char *buf, int len)
215 if (!(ml = new(struct msg_list)))
216 out_of_memory("msg_list_add");
218 if (!(ml->buf = new_array(char, len+4)))
219 out_of_memory("msg_list_add");
220 SIVAL(ml->buf, 0, ((code+MPLEX_BASE)<<24) | len);
221 memcpy(ml->buf+4, buf, len);
224 msg_list_tail->next = ml;
230 void send_msg(enum msgcode code, char *buf, int len)
232 if (msg_fd_out < 0) {
233 io_multiplex_write(code, buf, len);
236 msg_list_add(code, buf, len);
237 msg_list_push(NORMAL_FLUSH);
240 /* Read a message from the MSG_* fd and handle it. This is called either
241 * during the early stages of being a local sender (up through the sending
242 * of the file list) or when we're the generator (to fetch the messages
243 * from the receiver). */
244 static void read_msg_fd(void)
251 /* Temporarily disable msg_fd_in. This is needed to avoid looping back
252 * to this routine from writefd_unbuffered(). */
255 read_loop(fd, buf, 4);
258 len = tag & 0xFFFFFF;
259 tag = (tag >> 24) - MPLEX_BASE;
263 if (len != 0 || !am_generator) {
264 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
265 exit_cleanup(RERR_STREAMIO);
267 flist_ndx_push(&redo_list, -1);
270 if (len != 4 || !am_generator) {
271 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
272 exit_cleanup(RERR_STREAMIO);
274 read_loop(fd, buf, 4);
275 flist_ndx_push(&redo_list, IVAL(buf,0));
278 if (len >= (int)sizeof buf || !am_generator) {
279 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
280 exit_cleanup(RERR_STREAMIO);
282 read_loop(fd, buf, len);
283 io_multiplex_write(MSG_DELETED, buf, len);
286 if (len != 4 || !am_generator) {
287 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
288 exit_cleanup(RERR_STREAMIO);
290 read_loop(fd, buf, len);
291 if (remove_sent_files)
292 io_multiplex_write(MSG_SUCCESS, buf, len);
293 if (preserve_hard_links)
294 flist_ndx_push(&hlink_list, IVAL(buf,0));
303 read_loop(fd, buf, n);
304 rwrite((enum logcode)tag, buf, n);
309 rprintf(FERROR, "unknown message %d:%d\n", tag, len);
310 exit_cleanup(RERR_STREAMIO);
316 /* Try to push messages off the list onto the wire. If we leave with more
317 * to do, return 0. On error, return -1. If everything flushed, return 1.
318 * This is only active in the receiver. */
319 int msg_list_push(int flush_it_all)
321 static int written = 0;
328 while (msg_list_head) {
329 struct msg_list *ml = msg_list_head;
330 int n = write(msg_fd_out, ml->buf + written, ml->len - written);
334 if (errno != EWOULDBLOCK && errno != EAGAIN)
339 FD_SET(msg_fd_out, &fds);
340 tv.tv_sec = select_timeout;
342 if (!select(msg_fd_out+1, NULL, &fds, NULL, &tv))
344 } else if ((written += n) == ml->len) {
346 msg_list_head = ml->next;
348 msg_list_tail = NULL;
356 int get_redo_num(int itemizing, enum logcode code)
360 check_for_finished_hlinks(itemizing, code);
366 return flist_ndx_pop(&redo_list);
369 int get_hlink_num(void)
371 return flist_ndx_pop(&hlink_list);
375 * When we're the receiver and we have a local --files-from list of names
376 * that needs to be sent over the socket to the sender, we have to do two
377 * things at the same time: send the sender a list of what files we're
378 * processing and read the incoming file+info list from the sender. We do
379 * this by augmenting the read_timeout() function to copy this data. It
380 * uses the io_filesfrom_buf to read a block of data from f_in (when it is
381 * ready, since it might be a pipe) and then blast it out f_out (when it
382 * is ready to receive more data).
384 void io_set_filesfrom_fds(int f_in, int f_out)
386 io_filesfrom_f_in = f_in;
387 io_filesfrom_f_out = f_out;
388 io_filesfrom_bp = io_filesfrom_buf;
389 io_filesfrom_lastchar = '\0';
390 io_filesfrom_buflen = 0;
393 /* It's almost always an error to get an EOF when we're trying to read from the
394 * network, because the protocol is (for the most part) self-terminating.
396 * There is one case for the receiver when it is at the end of the transfer
397 * (hanging around reading any keep-alive packets that might come its way): if
398 * the sender dies before the generator's kill-signal comes through, we can end
399 * up here needing to loop until the kill-signal arrives. In this situation,
400 * kluge_around_eof will be < 0.
402 * There is another case for older protocol versions (< 24) where the module
403 * listing was not terminated, so we must ignore an EOF error in that case and
404 * exit. In this situation, kluge_around_eof will be > 0. */
405 static void whine_about_eof(int fd)
407 if (kluge_around_eof && fd == sock_f_in) {
409 if (kluge_around_eof > 0)
411 /* If we're still here after 10 seconds, exit with an error. */
412 for (i = 10*1000/20; i--; )
416 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
417 "(%.0f bytes received so far) [%s]\n",
418 (double)stats.total_read, who_am_i());
420 exit_cleanup(RERR_STREAMIO);
425 * Read from a socket with I/O timeout. return the number of bytes
426 * read. If no bytes can be read then exit, never return a number <= 0.
428 * TODO: If the remote shell connection fails, then current versions
429 * actually report an "unexpected EOF" error here. Since it's a
430 * fairly common mistake to try to use rsh when ssh is required, we
431 * should trap that: if we fail to read any data at all, we should
432 * give a better explanation. We can tell whether the connection has
433 * started by looking e.g. at whether the remote version is known yet.
435 static int read_timeout(int fd, char *buf, size_t len)
439 io_flush(NORMAL_FLUSH);
442 /* until we manage to read *something* */
452 FD_SET(msg_fd_out, &w_fds);
453 if (msg_fd_out > maxfd)
456 if (io_filesfrom_f_out >= 0) {
458 if (io_filesfrom_buflen == 0) {
459 if (io_filesfrom_f_in >= 0) {
460 FD_SET(io_filesfrom_f_in, &r_fds);
461 new_fd = io_filesfrom_f_in;
463 io_filesfrom_f_out = -1;
467 FD_SET(io_filesfrom_f_out, &w_fds);
468 new_fd = io_filesfrom_f_out;
474 tv.tv_sec = select_timeout;
479 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
483 exit_cleanup(RERR_SOCKETIO);
488 if (msg_list_head && FD_ISSET(msg_fd_out, &w_fds))
489 msg_list_push(NORMAL_FLUSH);
491 if (io_filesfrom_f_out >= 0) {
492 if (io_filesfrom_buflen) {
493 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
494 int l = write(io_filesfrom_f_out,
496 io_filesfrom_buflen);
498 if (!(io_filesfrom_buflen -= l))
499 io_filesfrom_bp = io_filesfrom_buf;
501 io_filesfrom_bp += l;
503 /* XXX should we complain? */
504 io_filesfrom_f_out = -1;
507 } else if (io_filesfrom_f_in >= 0) {
508 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
509 int l = read(io_filesfrom_f_in,
511 sizeof io_filesfrom_buf);
513 /* Send end-of-file marker */
514 io_filesfrom_buf[0] = '\0';
515 io_filesfrom_buf[1] = '\0';
516 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
517 io_filesfrom_f_in = -1;
520 char *s = io_filesfrom_buf + l;
521 /* Transform CR and/or LF into '\0' */
522 while (s-- > io_filesfrom_buf) {
523 if (*s == '\n' || *s == '\r')
527 if (!io_filesfrom_lastchar) {
528 /* Last buf ended with a '\0', so don't
529 * let this buf start with one. */
530 while (l && !*io_filesfrom_bp)
531 io_filesfrom_bp++, l--;
534 io_filesfrom_bp = io_filesfrom_buf;
536 char *f = io_filesfrom_bp;
539 /* Eliminate any multi-'\0' runs. */
541 if (!(*t++ = *f++)) {
542 while (f != eob && !*f)
546 io_filesfrom_lastchar = f[-1];
548 io_filesfrom_buflen = l;
554 if (!FD_ISSET(fd, &r_fds))
557 n = read(fd, buf, len);
561 whine_about_eof(fd); /* Doesn't return. */
562 if (errno == EINTR || errno == EWOULDBLOCK
566 /* Don't write errors on a dead socket. */
568 close_multiplexing_out();
569 rsyserr(FERROR, errno, "read error");
570 exit_cleanup(RERR_STREAMIO);
577 if (fd == sock_f_in && (io_timeout || am_generator))
578 last_io = time(NULL);
585 * Read a line into the "fname" buffer (which must be at least MAXPATHLEN
588 int read_filesfrom_line(int fd, char *fname)
590 char ch, *s, *eob = fname + MAXPATHLEN - 1;
592 int reading_remotely = filesfrom_host != NULL;
593 int nulls = eol_nulls || reading_remotely;
598 cnt = read(fd, &ch, 1);
599 if (cnt < 0 && (errno == EWOULDBLOCK
600 || errno == EINTR || errno == EAGAIN)) {
605 tv.tv_sec = select_timeout;
607 if (!select(fd+1, &fds, NULL, NULL, &tv))
613 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
614 /* Skip empty lines if reading locally. */
615 if (!reading_remotely && s == fname)
625 if (*fname == '#' || *fname == ';')
632 static char *iobuf_out;
633 static int iobuf_out_cnt;
635 void io_start_buffering_out(void)
639 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
640 out_of_memory("io_start_buffering_out");
645 static char *iobuf_in;
646 static size_t iobuf_in_siz;
648 void io_start_buffering_in(void)
652 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
653 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
654 out_of_memory("io_start_buffering_in");
658 void io_end_buffering(void)
660 io_flush(NORMAL_FLUSH);
661 if (!io_multiplexing_out) {
668 void maybe_flush_socket(void)
670 if (iobuf_out && iobuf_out_cnt && time(NULL) - last_io >= 5)
671 io_flush(NORMAL_FLUSH);
675 void maybe_send_keepalive(void)
677 if (time(NULL) - last_io >= allowed_lull) {
678 if (!iobuf_out || !iobuf_out_cnt) {
679 if (protocol_version < 29)
680 return; /* there's nothing we can do */
681 write_int(sock_f_out, the_file_list->count);
682 write_shortint(sock_f_out, ITEM_IS_NEW);
685 io_flush(NORMAL_FLUSH);
691 * Continue trying to read len bytes - don't return until len has been
694 static void read_loop(int fd, char *buf, size_t len)
697 int n = read_timeout(fd, buf, len);
706 * Read from the file descriptor handling multiplexing - return number
709 * Never returns <= 0.
711 static int readfd_unbuffered(int fd, char *buf, size_t len)
713 static size_t remaining;
714 static size_t iobuf_in_ndx;
717 #if MAXPATHLEN < 4096
718 char line[4096+1024];
720 char line[MAXPATHLEN+1024];
723 if (!iobuf_in || fd != sock_f_in)
724 return read_timeout(fd, buf, len);
726 if (!io_multiplexing_in && remaining == 0) {
727 remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
733 len = MIN(len, remaining);
734 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
741 read_loop(fd, line, 4);
744 msg_bytes = tag & 0xFFFFFF;
745 tag = (tag >> 24) - MPLEX_BASE;
749 if (msg_bytes > iobuf_in_siz) {
750 if (!(iobuf_in = realloc_array(iobuf_in, char,
752 out_of_memory("readfd_unbuffered");
753 iobuf_in_siz = msg_bytes;
755 read_loop(fd, iobuf_in, msg_bytes);
756 remaining = msg_bytes;
760 if (msg_bytes >= sizeof line)
762 read_loop(fd, line, msg_bytes);
763 line[msg_bytes] = '\0';
764 /* A directory name was sent with the trailing null */
765 if (msg_bytes > 0 && !line[msg_bytes-1])
766 log_delete(line, S_IFDIR);
768 log_delete(line, S_IFREG);
771 if (msg_bytes != 4) {
772 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
773 tag, (long)msg_bytes, who_am_i());
774 exit_cleanup(RERR_STREAMIO);
776 read_loop(fd, line, msg_bytes);
777 successful_send(IVAL(line, 0));
781 if (msg_bytes >= sizeof line) {
784 "multiplexing overflow %d:%ld [%s]\n",
785 tag, (long)msg_bytes, who_am_i());
786 exit_cleanup(RERR_STREAMIO);
788 read_loop(fd, line, msg_bytes);
789 rwrite((enum logcode)tag, line, msg_bytes);
792 rprintf(FERROR, "unexpected tag %d [%s]\n",
794 exit_cleanup(RERR_STREAMIO);
799 io_flush(NORMAL_FLUSH);
807 * Do a buffered read from @p fd. Don't return until all @p n bytes
808 * have been read. If all @p n can't be read then exit with an
811 static void readfd(int fd, char *buffer, size_t N)
817 ret = readfd_unbuffered(fd, buffer + total, N-total);
821 if (fd == write_batch_monitor_in) {
822 if ((size_t)write(batch_fd, buffer, total) != total)
823 exit_cleanup(RERR_FILEIO);
827 stats.total_read += total;
831 int read_shortint(int f)
834 readfd(f, (char *)b, 2);
835 return (b[1] << 8) + b[0];
839 int32 read_int(int f)
846 if (ret == (int32)0xffffffff)
851 int64 read_longint(int f)
857 if ((int32)ret != (int32)0xffffffff)
861 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
862 exit_cleanup(RERR_UNSUPPORTED);
865 ret = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
871 void read_buf(int f,char *buf,size_t len)
876 void read_sbuf(int f,char *buf,size_t len)
882 uchar read_byte(int f)
885 readfd(f, (char *)&c, 1);
889 int read_vstring(int f, char *buf, int bufsize)
891 int len = read_byte(f);
894 len = (len & ~0x80) * 0x100 + read_byte(f);
896 if (len >= bufsize) {
897 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
908 /* Populate a sum_struct with values from the socket. This is
909 * called by both the sender and the receiver. */
910 void read_sum_head(int f, struct sum_struct *sum)
912 sum->count = read_int(f);
913 sum->blength = read_int(f);
914 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
915 rprintf(FERROR, "Invalid block length %ld [%s]\n",
916 (long)sum->blength, who_am_i());
917 exit_cleanup(RERR_PROTOCOL);
919 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
920 if (sum->s2length < 0 || sum->s2length > MD4_SUM_LENGTH) {
921 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
922 sum->s2length, who_am_i());
923 exit_cleanup(RERR_PROTOCOL);
925 sum->remainder = read_int(f);
926 if (sum->remainder < 0 || sum->remainder > sum->blength) {
927 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
928 (long)sum->remainder, who_am_i());
929 exit_cleanup(RERR_PROTOCOL);
933 /* Send the values from a sum_struct over the socket. Set sum to
934 * NULL if there are no checksums to send. This is called by both
935 * the generator and the sender. */
936 void write_sum_head(int f, struct sum_struct *sum)
938 static struct sum_struct null_sum;
943 write_int(f, sum->count);
944 write_int(f, sum->blength);
945 if (protocol_version >= 27)
946 write_int(f, sum->s2length);
947 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);
1007 /* Write len bytes to the file descriptor fd, looping as necessary to get
1008 * the job done and also (in certain circumstnces) reading any data on
1009 * msg_fd_in to avoid deadlock.
1011 * This function underlies the multiplexing system. The body of the
1012 * application never calls this function directly. */
1013 static void writefd_unbuffered(int fd,char *buf,size_t len)
1015 size_t n, total = 0;
1016 fd_set w_fds, r_fds;
1017 int maxfd, count, ret, using_r_fds;
1022 while (total < len) {
1027 if (msg_fd_in >= 0 && len-total >= contiguous_write_len) {
1029 FD_SET(msg_fd_in,&r_fds);
1030 if (msg_fd_in > maxfd)
1036 tv.tv_sec = select_timeout;
1040 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1044 if (count < 0 && errno == EBADF)
1045 exit_cleanup(RERR_SOCKETIO);
1050 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1053 if (!FD_ISSET(fd, &w_fds))
1057 if (bwlimit && n > bwlimit_writemax)
1058 n = bwlimit_writemax;
1059 ret = write(fd, buf + total, n);
1065 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1071 /* Don't try to write errors back across the stream. */
1072 if (fd == sock_f_out)
1073 close_multiplexing_out();
1074 rsyserr(FERROR, errno,
1075 "writefd_unbuffered failed to write %ld bytes: phase \"%s\" [%s]",
1076 (long)len, io_write_phase, who_am_i());
1077 /* If the other side is sending us error messages, try
1078 * to grab any messages they sent before they died. */
1079 while (fd == sock_f_out && io_multiplexing_in) {
1080 io_timeout = select_timeout = 30;
1082 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1083 sizeof io_filesfrom_buf);
1085 exit_cleanup(RERR_STREAMIO);
1090 if (fd == sock_f_out) {
1091 if (io_timeout || am_generator)
1092 last_io = time(NULL);
1093 sleep_for_bwlimit(ret);
1102 * Write an message to a multiplexed stream. If this fails then rsync
1105 static void mplex_write(enum msgcode code, char *buf, size_t len)
1110 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
1112 /* When the generator reads messages from the msg_fd_in pipe, it can
1113 * cause output to occur down the socket. Setting contiguous_write_len
1114 * prevents the reading of msg_fd_in once we actually start to write
1115 * this sequence of data (though we might read it before the start). */
1116 if (am_generator && msg_fd_in >= 0)
1117 contiguous_write_len = len + 4;
1119 if (n > sizeof buffer - 4)
1120 n = sizeof buffer - 4;
1122 memcpy(&buffer[4], buf, n);
1123 writefd_unbuffered(sock_f_out, buffer, n+4);
1129 writefd_unbuffered(sock_f_out, buf, len);
1131 if (am_generator && msg_fd_in >= 0)
1132 contiguous_write_len = 0;
1136 void io_flush(int flush_it_all)
1138 msg_list_push(flush_it_all);
1140 if (!iobuf_out_cnt || no_flush)
1143 if (io_multiplexing_out)
1144 mplex_write(MSG_DATA, iobuf_out, iobuf_out_cnt);
1146 writefd_unbuffered(sock_f_out, iobuf_out, iobuf_out_cnt);
1151 static void writefd(int fd,char *buf,size_t len)
1153 if (fd == msg_fd_out) {
1154 rprintf(FERROR, "Internal error: wrong write used in receiver.\n");
1155 exit_cleanup(RERR_PROTOCOL);
1158 if (fd == sock_f_out)
1159 stats.total_written += len;
1161 if (fd == write_batch_monitor_out) {
1162 if ((size_t)write(batch_fd, buf, len) != len)
1163 exit_cleanup(RERR_FILEIO);
1166 if (!iobuf_out || fd != sock_f_out) {
1167 writefd_unbuffered(fd, buf, len);
1172 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1174 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1180 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1181 io_flush(NORMAL_FLUSH);
1186 void write_shortint(int f, int x)
1191 writefd(f, (char *)b, 2);
1195 void write_int(int f,int32 x)
1203 void write_int_named(int f, int32 x, const char *phase)
1205 io_write_phase = phase;
1207 io_write_phase = phase_unknown;
1212 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1213 * 64-bit types on this platform.
1215 void write_longint(int f, int64 x)
1219 if (x <= 0x7FFFFFFF) {
1220 write_int(f, (int)x);
1224 #if SIZEOF_INT64 < 8
1225 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1226 exit_cleanup(RERR_UNSUPPORTED);
1228 write_int(f, (int32)0xFFFFFFFF);
1229 SIVAL(b,0,(x&0xFFFFFFFF));
1230 SIVAL(b,4,((x>>32)&0xFFFFFFFF));
1236 void write_buf(int f,char *buf,size_t len)
1241 /** Write a string to the connection */
1242 void write_sbuf(int f, char *buf)
1244 writefd(f, buf, strlen(buf));
1247 void write_byte(int f, uchar c)
1249 writefd(f, (char *)&c, 1);
1252 void write_vstring(int f, char *str, int len)
1254 uchar lenbuf[3], *lb = lenbuf;
1259 "attempting to send over-long vstring (%d > %d)\n",
1261 exit_cleanup(RERR_PROTOCOL);
1263 *lb++ = len / 0x100 + 0x80;
1267 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1269 writefd(f, str, len);
1274 * Read a line of up to @p maxlen characters into @p buf (not counting
1275 * the trailing null). Strips the (required) trailing newline and all
1278 * @return 1 for success; 0 for I/O error or truncation.
1280 int read_line(int f, char *buf, size_t maxlen)
1284 read_buf(f, buf, 1);
1289 if (buf[0] != '\r') {
1299 void io_printf(int fd, const char *format, ...)
1305 va_start(ap, format);
1306 len = vsnprintf(buf, sizeof buf, format, ap);
1310 exit_cleanup(RERR_STREAMIO);
1312 write_sbuf(fd, buf);
1316 /** Setup for multiplexing a MSG_* stream with the data stream. */
1317 void io_start_multiplex_out(void)
1319 io_flush(NORMAL_FLUSH);
1320 io_start_buffering_out();
1321 io_multiplexing_out = 1;
1324 /** Setup for multiplexing a MSG_* stream with the data stream. */
1325 void io_start_multiplex_in(void)
1327 io_flush(NORMAL_FLUSH);
1328 io_start_buffering_in();
1329 io_multiplexing_in = 1;
1332 /** Write an message to the multiplexed data stream. */
1333 int io_multiplex_write(enum msgcode code, char *buf, size_t len)
1335 if (!io_multiplexing_out)
1338 io_flush(NORMAL_FLUSH);
1339 stats.total_written += (len+4);
1340 mplex_write(code, buf, len);
1344 void close_multiplexing_in(void)
1346 io_multiplexing_in = 0;
1349 /** Stop output multiplexing. */
1350 void close_multiplexing_out(void)
1352 io_multiplexing_out = 0;
1355 void start_write_batch(int fd)
1357 write_stream_flags(batch_fd);
1359 /* Some communication has already taken place, but we don't
1360 * enable batch writing until here so that we can write a
1361 * canonical record of the communication even though the
1362 * actual communication so far depends on whether a daemon
1364 write_int(batch_fd, protocol_version);
1365 write_int(batch_fd, checksum_seed);
1368 write_batch_monitor_out = fd;
1370 write_batch_monitor_in = fd;
1373 void stop_write_batch(void)
1375 write_batch_monitor_out = -1;
1376 write_batch_monitor_in = -1;