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));
305 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
306 exit_cleanup(RERR_STREAMIO);
308 close_multiplexing_out();
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 static int msg_list_flush(int flush_it_all)
335 static int written = 0;
342 while (msg_list.head) {
343 struct msg_list_item *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 void send_msg(enum msgcode code, char *buf, int len)
372 if (msg_fd_out < 0) {
373 io_multiplex_write(code, buf, len);
376 msg_list_add(code, buf, len);
377 msg_list_flush(NORMAL_FLUSH);
380 int get_redo_num(int itemizing, enum logcode code)
384 check_for_finished_hlinks(itemizing, code);
390 return flist_ndx_pop(&redo_list);
393 int get_hlink_num(void)
395 return flist_ndx_pop(&hlink_list);
399 * When we're the receiver and we have a local --files-from list of names
400 * that needs to be sent over the socket to the sender, we have to do two
401 * things at the same time: send the sender a list of what files we're
402 * processing and read the incoming file+info list from the sender. We do
403 * this by augmenting the read_timeout() function to copy this data. It
404 * uses the io_filesfrom_buf to read a block of data from f_in (when it is
405 * ready, since it might be a pipe) and then blast it out f_out (when it
406 * is ready to receive more data).
408 void io_set_filesfrom_fds(int f_in, int f_out)
410 io_filesfrom_f_in = f_in;
411 io_filesfrom_f_out = f_out;
412 io_filesfrom_bp = io_filesfrom_buf;
413 io_filesfrom_lastchar = '\0';
414 io_filesfrom_buflen = 0;
417 /* It's almost always an error to get an EOF when we're trying to read from the
418 * network, because the protocol is (for the most part) self-terminating.
420 * There is one case for the receiver when it is at the end of the transfer
421 * (hanging around reading any keep-alive packets that might come its way): if
422 * the sender dies before the generator's kill-signal comes through, we can end
423 * up here needing to loop until the kill-signal arrives. In this situation,
424 * kluge_around_eof will be < 0.
426 * There is another case for older protocol versions (< 24) where the module
427 * listing was not terminated, so we must ignore an EOF error in that case and
428 * exit. In this situation, kluge_around_eof will be > 0. */
429 static void whine_about_eof(int fd)
431 if (kluge_around_eof && fd == sock_f_in) {
433 if (kluge_around_eof > 0)
435 /* If we're still here after 10 seconds, exit with an error. */
436 for (i = 10*1000/20; i--; )
440 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
441 "(%.0f bytes received so far) [%s]\n",
442 (double)stats.total_read, who_am_i());
444 exit_cleanup(RERR_STREAMIO);
448 * Read from a socket with I/O timeout. return the number of bytes
449 * read. If no bytes can be read then exit, never return a number <= 0.
451 * TODO: If the remote shell connection fails, then current versions
452 * actually report an "unexpected EOF" error here. Since it's a
453 * fairly common mistake to try to use rsh when ssh is required, we
454 * should trap that: if we fail to read any data at all, we should
455 * give a better explanation. We can tell whether the connection has
456 * started by looking e.g. at whether the remote version is known yet.
458 static int read_timeout(int fd, char *buf, size_t len)
462 io_flush(NORMAL_FLUSH);
465 /* until we manage to read *something* */
475 FD_SET(msg_fd_out, &w_fds);
476 if (msg_fd_out > maxfd)
479 if (io_filesfrom_f_out >= 0) {
481 if (io_filesfrom_buflen == 0) {
482 if (io_filesfrom_f_in >= 0) {
483 FD_SET(io_filesfrom_f_in, &r_fds);
484 new_fd = io_filesfrom_f_in;
486 io_filesfrom_f_out = -1;
490 FD_SET(io_filesfrom_f_out, &w_fds);
491 new_fd = io_filesfrom_f_out;
497 tv.tv_sec = select_timeout;
502 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
506 exit_cleanup(RERR_SOCKETIO);
511 if (msg_list.head && FD_ISSET(msg_fd_out, &w_fds))
512 msg_list_flush(NORMAL_FLUSH);
514 if (io_filesfrom_f_out >= 0) {
515 if (io_filesfrom_buflen) {
516 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
517 int l = write(io_filesfrom_f_out,
519 io_filesfrom_buflen);
521 if (!(io_filesfrom_buflen -= l))
522 io_filesfrom_bp = io_filesfrom_buf;
524 io_filesfrom_bp += l;
526 /* XXX should we complain? */
527 io_filesfrom_f_out = -1;
530 } else if (io_filesfrom_f_in >= 0) {
531 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
532 int l = read(io_filesfrom_f_in,
534 sizeof io_filesfrom_buf);
536 /* Send end-of-file marker */
537 io_filesfrom_buf[0] = '\0';
538 io_filesfrom_buf[1] = '\0';
539 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
540 io_filesfrom_f_in = -1;
543 char *s = io_filesfrom_buf + l;
544 /* Transform CR and/or LF into '\0' */
545 while (s-- > io_filesfrom_buf) {
546 if (*s == '\n' || *s == '\r')
550 if (!io_filesfrom_lastchar) {
551 /* Last buf ended with a '\0', so don't
552 * let this buf start with one. */
553 while (l && !*io_filesfrom_bp)
554 io_filesfrom_bp++, l--;
557 io_filesfrom_bp = io_filesfrom_buf;
559 char *f = io_filesfrom_bp;
562 /* Eliminate any multi-'\0' runs. */
564 if (!(*t++ = *f++)) {
565 while (f != eob && !*f)
569 io_filesfrom_lastchar = f[-1];
571 io_filesfrom_buflen = l;
577 if (!FD_ISSET(fd, &r_fds))
580 n = read(fd, buf, len);
584 whine_about_eof(fd); /* Doesn't return. */
585 if (errno == EINTR || errno == EWOULDBLOCK
589 /* Don't write errors on a dead socket. */
590 if (fd == sock_f_in) {
591 close_multiplexing_out();
592 rsyserr(FSOCKERR, errno, "read error");
594 rsyserr(FERROR, errno, "read error");
595 exit_cleanup(RERR_STREAMIO);
602 if (fd == sock_f_in && io_timeout)
603 last_io_in = time(NULL);
610 * Read a line into the "fname" buffer (which must be at least MAXPATHLEN
613 int read_filesfrom_line(int fd, char *fname)
615 char ch, *s, *eob = fname + MAXPATHLEN - 1;
617 int reading_remotely = filesfrom_host != NULL;
618 int nulls = eol_nulls || reading_remotely;
623 cnt = read(fd, &ch, 1);
624 if (cnt < 0 && (errno == EWOULDBLOCK
625 || errno == EINTR || errno == EAGAIN)) {
630 tv.tv_sec = select_timeout;
632 if (!select(fd+1, &fds, NULL, NULL, &tv))
638 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
639 /* Skip empty lines if reading locally. */
640 if (!reading_remotely && s == fname)
650 if (*fname == '#' || *fname == ';')
656 static char *iobuf_out;
657 static int iobuf_out_cnt;
659 void io_start_buffering_out(void)
663 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
664 out_of_memory("io_start_buffering_out");
668 static char *iobuf_in;
669 static size_t iobuf_in_siz;
671 void io_start_buffering_in(void)
675 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
676 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
677 out_of_memory("io_start_buffering_in");
680 void io_end_buffering(void)
682 io_flush(NORMAL_FLUSH);
683 if (!io_multiplexing_out) {
689 void maybe_flush_socket(void)
691 if (iobuf_out && iobuf_out_cnt && time(NULL) - last_io_out >= 5)
692 io_flush(NORMAL_FLUSH);
695 void maybe_send_keepalive(void)
697 if (time(NULL) - last_io_out >= allowed_lull) {
698 if (!iobuf_out || !iobuf_out_cnt) {
699 if (protocol_version < 29)
700 return; /* there's nothing we can do */
701 write_int(sock_f_out, the_file_list->count);
702 write_shortint(sock_f_out, ITEM_IS_NEW);
705 io_flush(NORMAL_FLUSH);
710 * Continue trying to read len bytes - don't return until len has been
713 static void read_loop(int fd, char *buf, size_t len)
716 int n = read_timeout(fd, buf, len);
724 * Read from the file descriptor handling multiplexing - return number
727 * Never returns <= 0.
729 static int readfd_unbuffered(int fd, char *buf, size_t len)
731 static size_t remaining;
732 static size_t iobuf_in_ndx;
735 char line[BIGPATHBUFLEN];
737 if (!iobuf_in || fd != sock_f_in)
738 return read_timeout(fd, buf, len);
740 if (!io_multiplexing_in && remaining == 0) {
741 remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
747 len = MIN(len, remaining);
748 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
755 read_loop(fd, line, 4);
758 msg_bytes = tag & 0xFFFFFF;
759 tag = (tag >> 24) - MPLEX_BASE;
763 if (msg_bytes > iobuf_in_siz) {
764 if (!(iobuf_in = realloc_array(iobuf_in, char,
766 out_of_memory("readfd_unbuffered");
767 iobuf_in_siz = msg_bytes;
769 read_loop(fd, iobuf_in, msg_bytes);
770 remaining = msg_bytes;
774 if (msg_bytes >= sizeof line)
776 read_loop(fd, line, msg_bytes);
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 line[msg_bytes] = '\0';
782 log_delete(line, S_IFREG);
786 if (msg_bytes != 4) {
787 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
788 tag, (long)msg_bytes, who_am_i());
789 exit_cleanup(RERR_STREAMIO);
791 read_loop(fd, line, msg_bytes);
792 successful_send(IVAL(line, 0));
796 if (msg_bytes >= sizeof line) {
799 "multiplexing overflow %d:%ld [%s]\n",
800 tag, (long)msg_bytes, who_am_i());
801 exit_cleanup(RERR_STREAMIO);
803 read_loop(fd, line, msg_bytes);
804 rwrite((enum logcode)tag, line, msg_bytes);
807 rprintf(FERROR, "unexpected tag %d [%s]\n",
809 exit_cleanup(RERR_STREAMIO);
814 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 cnt = 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;
843 int read_shortint(int f)
846 readfd(f, (char *)b, 2);
847 return (b[1] << 8) + b[0];
850 int32 read_int(int f)
857 if (num == (int32)0xffffffff)
862 int64 read_longint(int f)
868 if ((int32)num != (int32)0xffffffff)
872 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
873 exit_cleanup(RERR_UNSUPPORTED);
876 num = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
882 void read_buf(int f,char *buf,size_t len)
887 void read_sbuf(int f,char *buf,size_t len)
893 uchar read_byte(int f)
896 readfd(f, (char *)&c, 1);
900 int read_vstring(int f, char *buf, int bufsize)
902 int len = read_byte(f);
905 len = (len & ~0x80) * 0x100 + read_byte(f);
907 if (len >= bufsize) {
908 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
919 /* Populate a sum_struct with values from the socket. This is
920 * called by both the sender and the receiver. */
921 void read_sum_head(int f, struct sum_struct *sum)
923 sum->count = read_int(f);
924 sum->blength = read_int(f);
925 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
926 rprintf(FERROR, "Invalid block length %ld [%s]\n",
927 (long)sum->blength, who_am_i());
928 exit_cleanup(RERR_PROTOCOL);
930 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
931 if (sum->s2length < 0 || sum->s2length > MD4_SUM_LENGTH) {
932 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
933 sum->s2length, who_am_i());
934 exit_cleanup(RERR_PROTOCOL);
936 sum->remainder = read_int(f);
937 if (sum->remainder < 0 || sum->remainder > sum->blength) {
938 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
939 (long)sum->remainder, who_am_i());
940 exit_cleanup(RERR_PROTOCOL);
944 /* Send the values from a sum_struct over the socket. Set sum to
945 * NULL if there are no checksums to send. This is called by both
946 * the generator and the sender. */
947 void write_sum_head(int f, struct sum_struct *sum)
949 static struct sum_struct null_sum;
954 write_int(f, sum->count);
955 write_int(f, sum->blength);
956 if (protocol_version >= 27)
957 write_int(f, sum->s2length);
958 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);
1016 /* Write len bytes to the file descriptor fd, looping as necessary to get
1017 * the job done and also (in certain circumstances) reading any data on
1018 * msg_fd_in to avoid deadlock.
1020 * This function underlies the multiplexing system. The body of the
1021 * application never calls this function directly. */
1022 static void writefd_unbuffered(int fd,char *buf,size_t len)
1024 size_t n, total = 0;
1025 fd_set w_fds, r_fds;
1026 int maxfd, count, cnt, using_r_fds;
1031 while (total < len) {
1036 if (msg_fd_in >= 0 && len-total >= contiguous_write_len) {
1038 FD_SET(msg_fd_in,&r_fds);
1039 if (msg_fd_in > maxfd)
1045 tv.tv_sec = select_timeout;
1049 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1053 if (count < 0 && errno == EBADF)
1054 exit_cleanup(RERR_SOCKETIO);
1059 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1062 if (!FD_ISSET(fd, &w_fds))
1066 if (bwlimit && n > bwlimit_writemax)
1067 n = bwlimit_writemax;
1068 cnt = write(fd, buf + total, n);
1074 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1080 /* Don't try to write errors back across the stream. */
1081 if (fd == sock_f_out)
1082 close_multiplexing_out();
1083 rsyserr(FERROR, errno,
1084 "writefd_unbuffered failed to write %ld bytes: phase \"%s\" [%s]",
1085 (long)len, io_write_phase, who_am_i());
1086 /* If the other side is sending us error messages, try
1087 * to grab any messages they sent before they died. */
1088 while (fd == sock_f_out && io_multiplexing_in) {
1091 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1092 sizeof io_filesfrom_buf);
1094 exit_cleanup(RERR_STREAMIO);
1099 if (fd == sock_f_out) {
1100 if (io_timeout || am_generator)
1101 last_io_out = time(NULL);
1102 sleep_for_bwlimit(cnt);
1110 * Write an message to a multiplexed stream. If this fails then rsync
1113 static void mplex_write(enum msgcode code, char *buf, size_t len)
1118 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
1120 /* When the generator reads messages from the msg_fd_in pipe, it can
1121 * cause output to occur down the socket. Setting contiguous_write_len
1122 * prevents the reading of msg_fd_in once we actually start to write
1123 * this sequence of data (though we might read it before the start). */
1124 if (am_generator && msg_fd_in >= 0)
1125 contiguous_write_len = len + 4;
1127 if (n > sizeof buffer - 4)
1130 memcpy(buffer + 4, buf, n);
1132 writefd_unbuffered(sock_f_out, buffer, n+4);
1138 writefd_unbuffered(sock_f_out, buf, len);
1140 if (am_generator && msg_fd_in >= 0)
1141 contiguous_write_len = 0;
1144 void io_flush(int flush_it_all)
1146 msg_list_flush(flush_it_all);
1148 if (!iobuf_out_cnt || no_flush)
1151 if (io_multiplexing_out)
1152 mplex_write(MSG_DATA, iobuf_out, iobuf_out_cnt);
1154 writefd_unbuffered(sock_f_out, iobuf_out, iobuf_out_cnt);
1158 static void writefd(int fd,char *buf,size_t len)
1160 if (fd == msg_fd_out) {
1161 rprintf(FERROR, "Internal error: wrong write used in receiver.\n");
1162 exit_cleanup(RERR_PROTOCOL);
1165 if (fd == sock_f_out)
1166 stats.total_written += len;
1168 if (fd == write_batch_monitor_out) {
1169 if ((size_t)write(batch_fd, buf, len) != len)
1170 exit_cleanup(RERR_FILEIO);
1173 if (!iobuf_out || fd != sock_f_out) {
1174 writefd_unbuffered(fd, buf, len);
1179 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1181 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1187 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1188 io_flush(NORMAL_FLUSH);
1192 void write_shortint(int f, int x)
1197 writefd(f, (char *)b, 2);
1200 void write_int(int f,int32 x)
1207 void write_int_named(int f, int32 x, const char *phase)
1209 io_write_phase = phase;
1211 io_write_phase = phase_unknown;
1215 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1216 * 64-bit types on this platform.
1218 void write_longint(int f, int64 x)
1222 if (x <= 0x7FFFFFFF) {
1223 write_int(f, (int)x);
1227 #if SIZEOF_INT64 < 8
1228 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1229 exit_cleanup(RERR_UNSUPPORTED);
1231 write_int(f, (int32)0xFFFFFFFF);
1232 SIVAL(b,0,(x&0xFFFFFFFF));
1233 SIVAL(b,4,((x>>32)&0xFFFFFFFF));
1239 void write_buf(int f,char *buf,size_t len)
1244 /** Write a string to the connection */
1245 void write_sbuf(int f, char *buf)
1247 writefd(f, buf, strlen(buf));
1250 void write_byte(int f, uchar c)
1252 writefd(f, (char *)&c, 1);
1255 void write_vstring(int f, char *str, int len)
1257 uchar lenbuf[3], *lb = lenbuf;
1262 "attempting to send over-long vstring (%d > %d)\n",
1264 exit_cleanup(RERR_PROTOCOL);
1266 *lb++ = len / 0x100 + 0x80;
1270 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1272 writefd(f, str, len);
1276 * Read a line of up to @p maxlen characters into @p buf (not counting
1277 * the trailing null). Strips the (required) trailing newline and all
1280 * @return 1 for success; 0 for I/O error or truncation.
1282 int read_line(int f, char *buf, size_t maxlen)
1286 read_buf(f, buf, 1);
1291 if (buf[0] != '\r') {
1300 void io_printf(int fd, const char *format, ...)
1303 char buf[BIGPATHBUFLEN];
1306 va_start(ap, format);
1307 len = vsnprintf(buf, sizeof buf, format, ap);
1311 exit_cleanup(RERR_STREAMIO);
1313 if (len > (int)sizeof buf) {
1314 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1315 exit_cleanup(RERR_STREAMIO);
1318 write_sbuf(fd, buf);
1321 /** Setup for multiplexing a MSG_* stream with the data stream. */
1322 void io_start_multiplex_out(void)
1324 io_flush(NORMAL_FLUSH);
1325 io_start_buffering_out();
1326 io_multiplexing_out = 1;
1329 /** Setup for multiplexing a MSG_* stream with the data stream. */
1330 void io_start_multiplex_in(void)
1332 io_flush(NORMAL_FLUSH);
1333 io_start_buffering_in();
1334 io_multiplexing_in = 1;
1337 /** Write an message to the multiplexed data stream. */
1338 int io_multiplex_write(enum msgcode code, char *buf, size_t len)
1340 if (!io_multiplexing_out)
1343 io_flush(NORMAL_FLUSH);
1344 stats.total_written += (len+4);
1345 mplex_write(code, buf, len);
1349 void close_multiplexing_in(void)
1351 io_multiplexing_in = 0;
1354 /** Stop output multiplexing. */
1355 void close_multiplexing_out(void)
1357 io_multiplexing_out = 0;
1360 void start_write_batch(int fd)
1362 write_stream_flags(batch_fd);
1364 /* Some communication has already taken place, but we don't
1365 * enable batch writing until here so that we can write a
1366 * canonical record of the communication even though the
1367 * actual communication so far depends on whether a daemon
1369 write_int(batch_fd, protocol_version);
1370 write_int(batch_fd, checksum_seed);
1373 write_batch_monitor_out = fd;
1375 write_batch_monitor_in = fd;
1378 void stop_write_batch(void)
1380 write_batch_monitor_out = -1;
1381 write_batch_monitor_in = -1;