2 * Socket and pipe I/O utilities used in rsync.
4 * Copyright (C) 1996-2001 Andrew Tridgell
5 * Copyright (C) 1996 Paul Mackerras
6 * Copyright (C) 2001, 2002 Martin Pool <mbp@samba.org>
7 * Copyright (C) 2003-2007 Wayne Davison
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
23 /* Rsync provides its own multiplexing system, which is used to send
24 * stderr and stdout over a single socket.
26 * For historical reasons this is off during the start of the
27 * connection, but it's switched on quite early using
28 * io_start_multiplex_out() and io_start_multiplex_in(). */
32 /** If no timeout is specified then use a 60 second select timeout */
33 #define SELECT_TIMEOUT 60
36 extern size_t bwlimit_writemax;
37 extern int io_timeout;
38 extern int allowed_lull;
42 extern int am_generator;
43 extern int inc_recurse;
47 extern int read_batch;
48 extern int csum_length;
49 extern int checksum_seed;
50 extern int protocol_version;
51 extern int remove_source_files;
52 extern int preserve_hard_links;
53 extern char *filesfrom_host;
54 extern struct stats stats;
55 extern struct file_list *cur_flist, *first_flist;
57 extern iconv_t ic_send, ic_recv;
60 const char phase_unknown[] = "unknown";
61 int ignore_timeout = 0;
65 /* Ignore an EOF error if non-zero. See whine_about_eof(). */
66 int kluge_around_eof = 0;
73 static int iobuf_f_in = -1;
74 static char *iobuf_in;
75 static size_t iobuf_in_siz;
76 static size_t iobuf_in_ndx;
77 static size_t iobuf_in_remaining;
79 static int iobuf_f_out = -1;
80 static char *iobuf_out;
81 static int iobuf_out_cnt;
83 int flist_forward_from = -1;
85 static int io_multiplexing_out;
86 static int io_multiplexing_in;
87 static time_t last_io_in;
88 static time_t last_io_out;
91 static int write_batch_monitor_in = -1;
92 static int write_batch_monitor_out = -1;
94 static int io_filesfrom_f_in = -1;
95 static int io_filesfrom_f_out = -1;
96 static char io_filesfrom_buf[2048];
98 static char iconv_buf[sizeof io_filesfrom_buf / 2];
100 static char *io_filesfrom_bp;
101 static char io_filesfrom_lastchar;
102 static int io_filesfrom_buflen;
103 static int defer_forwarding_messages = 0;
104 static int select_timeout = SELECT_TIMEOUT;
105 static int active_filecnt = 0;
106 static OFF_T active_bytecnt = 0;
108 static char int_byte_extra[64] = {
109 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* (00 - 3F)/4 */
110 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* (40 - 7F)/4 */
111 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* (80 - BF)/4 */
112 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 5, 6, /* (C0 - FF)/4 */
115 static void readfd(int fd, char *buffer, size_t N);
116 static void writefd(int fd, const char *buf, size_t len);
117 static void writefd_unbuffered(int fd, const char *buf, size_t len);
118 static void decrement_active_files(int ndx);
119 static void decrement_flist_in_progress(int ndx, int redo);
120 static void mplex_write(int fd, enum msgcode code, const char *buf, size_t len, int convert);
122 struct flist_ndx_item {
123 struct flist_ndx_item *next;
127 struct flist_ndx_list {
128 struct flist_ndx_item *head, *tail;
131 static struct flist_ndx_list redo_list, hlink_list;
133 struct msg_list_item {
134 struct msg_list_item *next;
140 struct msg_list_item *head, *tail;
143 static struct msg_list msg_queue;
145 static void flist_ndx_push(struct flist_ndx_list *lp, int ndx)
147 struct flist_ndx_item *item;
149 if (!(item = new(struct flist_ndx_item)))
150 out_of_memory("flist_ndx_push");
154 lp->tail->next = item;
160 static int flist_ndx_pop(struct flist_ndx_list *lp)
162 struct flist_ndx_item *next;
169 next = lp->head->next;
178 static void check_timeout(void)
182 if (!io_timeout || ignore_timeout)
186 last_io_in = time(NULL);
192 if (t - last_io_in >= io_timeout) {
193 if (!am_server && !am_daemon) {
194 rprintf(FERROR, "io timeout after %d seconds -- exiting\n",
195 (int)(t-last_io_in));
197 exit_cleanup(RERR_TIMEOUT);
201 /* Note the fds used for the main socket (which might really be a pipe
202 * for a local transfer, but we can ignore that). */
203 void io_set_sock_fds(int f_in, int f_out)
209 void set_io_timeout(int secs)
213 if (!io_timeout || io_timeout > SELECT_TIMEOUT)
214 select_timeout = SELECT_TIMEOUT;
216 select_timeout = io_timeout;
218 allowed_lull = read_batch ? 0 : (io_timeout + 1) / 2;
221 /* Setup the fd used to receive MSG_* messages. Only needed during the
222 * early stages of being a local sender (up through the sending of the
223 * file list) or when we're the generator (to fetch the messages from
225 void set_msg_fd_in(int fd)
230 /* Setup the fd used to send our MSG_* messages. Only needed when
231 * we're the receiver (to send our messages to the generator). */
232 void set_msg_fd_out(int fd)
235 set_nonblocking(msg_fd_out);
238 /* Add a message to the pending MSG_* list. */
239 static void msg_list_add(struct msg_list *lst, int code, const char *buf, int len, int convert)
241 struct msg_list_item *m;
242 int sz = len + 4 + sizeof m[0] - 1;
244 if (!(m = (struct msg_list_item *)new_array(char, sz)))
245 out_of_memory("msg_list_add");
247 m->convert = convert;
248 SIVAL(m->buf, 0, ((code+MPLEX_BASE)<<24) | len);
249 memcpy(m->buf + 4, buf, len);
257 static void msg_flush(void)
260 while (msg_queue.head && io_multiplexing_out) {
261 struct msg_list_item *m = msg_queue.head;
262 int len = IVAL(m->buf, 0) & 0xFFFFFF;
263 int tag = *((uchar*)m->buf+3) - MPLEX_BASE;
264 if (!(msg_queue.head = m->next))
265 msg_queue.tail = NULL;
266 stats.total_written += len + 4;
267 defer_forwarding_messages++;
268 mplex_write(sock_f_out, tag, m->buf + 4, len, m->convert);
269 defer_forwarding_messages--;
273 while (msg_queue.head) {
274 struct msg_list_item *m = msg_queue.head;
275 int len = IVAL(m->buf, 0) & 0xFFFFFF;
276 int tag = *((uchar*)m->buf+3) - MPLEX_BASE;
277 if (!(msg_queue.head = m->next))
278 msg_queue.tail = NULL;
279 defer_forwarding_messages++;
280 mplex_write(msg_fd_out, tag, m->buf + 4, len, m->convert);
281 defer_forwarding_messages--;
287 /* Read a message from the MSG_* fd and handle it. This is called either
288 * during the early stages of being a local sender (up through the sending
289 * of the file list) or when we're the generator (to fetch the messages
290 * from the receiver). */
291 static void read_msg_fd(void)
295 struct file_list *flist;
299 /* Temporarily disable msg_fd_in. This is needed to avoid looping back
300 * to this routine from writefd_unbuffered(). */
303 defer_forwarding_messages++;
308 len = tag & 0xFFFFFF;
309 tag = (tag >> 24) - MPLEX_BASE;
313 if (len < 0 || len > 1 || !am_generator) {
315 rprintf(FERROR, "invalid message %d:%d [%s%s]\n",
316 tag, len, who_am_i(),
317 inc_recurse ? "/inc" : "");
318 exit_cleanup(RERR_STREAMIO);
321 readfd(fd, buf, len);
322 stats.total_read = read_varlong(fd, 3);
327 if (len != 4 || !am_generator)
330 if (remove_source_files)
331 decrement_active_files(IVAL(buf,0));
332 flist_ndx_push(&redo_list, IVAL(buf,0));
334 decrement_flist_in_progress(IVAL(buf,0), 1);
337 if (len != 4 || !am_generator || !inc_recurse)
340 /* Read extra file list from receiver. */
341 assert(iobuf_in != NULL);
342 assert(iobuf_f_in == fd);
344 rprintf(FINFO, "[%s] receiving flist for dir %d\n",
345 who_am_i(), IVAL(buf,0));
347 flist = recv_file_list(fd);
348 flist->parent_ndx = IVAL(buf,0);
351 if (len != 0 || !am_generator || !inc_recurse)
356 if (len >= (int)sizeof buf || !am_generator)
358 readfd(fd, buf, len);
359 send_msg(MSG_DELETED, buf, len, 1);
362 if (len != 4 || !am_generator)
364 readfd(fd, buf, len);
365 if (remove_source_files) {
366 decrement_active_files(IVAL(buf,0));
367 send_msg(MSG_SUCCESS, buf, len, 0);
369 if (preserve_hard_links)
370 flist_ndx_push(&hlink_list, IVAL(buf,0));
372 decrement_flist_in_progress(IVAL(buf,0), 0);
375 if (len != 4 || !am_generator)
377 readfd(fd, buf, len);
379 decrement_flist_in_progress(IVAL(buf,0), 0);
385 if (tag == MSG_SOCKERR)
386 io_end_multiplex_out();
396 rwrite((enum logcode)tag, buf, n, !am_generator);
401 rprintf(FERROR, "unknown message %d:%d [%s]\n",
402 tag, len, who_am_i());
403 exit_cleanup(RERR_STREAMIO);
408 if (!--defer_forwarding_messages)
412 /* This is used by the generator to limit how many file transfers can
413 * be active at once when --remove-source-files is specified. Without
414 * this, sender-side deletions were mostly happening at the end. */
415 void increment_active_files(int ndx, int itemizing, enum logcode code)
417 /* TODO: tune these limits? */
418 while (active_filecnt >= (active_bytecnt >= 128*1024 ? 10 : 50)) {
419 check_for_finished_files(itemizing, code, 0);
421 io_flush(NORMAL_FLUSH);
427 active_bytecnt += F_LENGTH(cur_flist->files[ndx - cur_flist->ndx_start]);
430 static void decrement_active_files(int ndx)
432 struct file_list *flist = flist_for_ndx(ndx);
433 assert(flist != NULL);
435 active_bytecnt -= F_LENGTH(flist->files[ndx - flist->ndx_start]);
438 static void decrement_flist_in_progress(int ndx, int redo)
440 struct file_list *flist = cur_flist ? cur_flist : first_flist;
442 while (ndx < flist->ndx_start) {
443 if (flist == first_flist) {
446 "Invalid file index: %d (%d - %d) [%s]\n",
447 ndx, first_flist->ndx_start,
448 first_flist->prev->ndx_start + first_flist->prev->count - 1,
450 exit_cleanup(RERR_PROTOCOL);
454 while (ndx >= flist->ndx_start + flist->count) {
455 if (!(flist = flist->next))
459 flist->in_progress--;
464 /* Write an message to a multiplexed stream. If this fails, rsync exits. */
465 static void mplex_write(int fd, enum msgcode code, const char *buf, size_t len, int convert)
467 char buffer[BIGPATHBUFLEN]; /* Oversized for use by iconv code. */
470 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
473 if (convert && ic_send == (iconv_t)-1)
477 if (convert || n > 1024 - 4) /* BIGPATHBUFLEN can handle 1024 bytes */
480 memcpy(buffer + 4, buf, n);
482 writefd_unbuffered(fd, buffer, n+4);
489 iconv(ic_send, NULL, 0, NULL, 0);
490 defer_forwarding_messages++;
492 ICONV_CONST char *ibuf = (ICONV_CONST char *)buf;
494 size_t ocnt = sizeof buffer;
495 while (len && iconv(ic_send, &ibuf,&len,
496 &obuf,&ocnt) == (size_t)-1) {
497 if (errno == E2BIG || !ocnt)
503 writefd_unbuffered(fd, buffer, n);
505 if (!--defer_forwarding_messages)
510 defer_forwarding_messages++;
511 writefd_unbuffered(fd, buf, len);
512 if (!--defer_forwarding_messages)
517 int send_msg(enum msgcode code, const char *buf, int len, int convert)
519 if (msg_fd_out < 0) {
520 if (!defer_forwarding_messages)
521 return io_multiplex_write(code, buf, len, convert);
522 if (!io_multiplexing_out)
524 msg_list_add(&msg_queue, code, buf, len, convert);
527 if (flist_forward_from >= 0)
528 msg_list_add(&msg_queue, code, buf, len, convert);
530 mplex_write(msg_fd_out, code, buf, len, convert);
534 void send_msg_int(enum msgcode code, int num)
537 SIVAL(numbuf, 0, num);
538 send_msg(code, numbuf, 4, 0);
541 void wait_for_receiver(void)
544 io_flush(NORMAL_FLUSH);
549 int get_redo_num(void)
551 return flist_ndx_pop(&redo_list);
554 int get_hlink_num(void)
556 return flist_ndx_pop(&hlink_list);
560 * When we're the receiver and we have a local --files-from list of names
561 * that needs to be sent over the socket to the sender, we have to do two
562 * things at the same time: send the sender a list of what files we're
563 * processing and read the incoming file+info list from the sender. We do
564 * this by augmenting the read_timeout() function to copy this data. It
565 * uses the io_filesfrom_buf to read a block of data from f_in (when it is
566 * ready, since it might be a pipe) and then blast it out f_out (when it
567 * is ready to receive more data).
569 void io_set_filesfrom_fds(int f_in, int f_out)
571 io_filesfrom_f_in = f_in;
572 io_filesfrom_f_out = f_out;
573 io_filesfrom_bp = io_filesfrom_buf;
574 io_filesfrom_lastchar = '\0';
575 io_filesfrom_buflen = 0;
578 /* It's almost always an error to get an EOF when we're trying to read from the
579 * network, because the protocol is (for the most part) self-terminating.
581 * There is one case for the receiver when it is at the end of the transfer
582 * (hanging around reading any keep-alive packets that might come its way): if
583 * the sender dies before the generator's kill-signal comes through, we can end
584 * up here needing to loop until the kill-signal arrives. In this situation,
585 * kluge_around_eof will be < 0.
587 * There is another case for older protocol versions (< 24) where the module
588 * listing was not terminated, so we must ignore an EOF error in that case and
589 * exit. In this situation, kluge_around_eof will be > 0. */
590 static void whine_about_eof(int fd)
592 if (kluge_around_eof && fd == sock_f_in) {
594 if (kluge_around_eof > 0)
596 /* If we're still here after 10 seconds, exit with an error. */
597 for (i = 10*1000/20; i--; )
601 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
602 "(%.0f bytes received so far) [%s]\n",
603 (double)stats.total_read, who_am_i());
605 exit_cleanup(RERR_STREAMIO);
609 * Read from a socket with I/O timeout. return the number of bytes
610 * read. If no bytes can be read then exit, never return a number <= 0.
612 * TODO: If the remote shell connection fails, then current versions
613 * actually report an "unexpected EOF" error here. Since it's a
614 * fairly common mistake to try to use rsh when ssh is required, we
615 * should trap that: if we fail to read any data at all, we should
616 * give a better explanation. We can tell whether the connection has
617 * started by looking e.g. at whether the remote version is known yet.
619 static int read_timeout(int fd, char *buf, size_t len)
623 io_flush(FULL_FLUSH);
626 /* until we manage to read *something* */
635 if (io_filesfrom_f_out >= 0) {
637 if (io_filesfrom_buflen == 0) {
638 if (io_filesfrom_f_in >= 0) {
639 FD_SET(io_filesfrom_f_in, &r_fds);
640 new_fd = io_filesfrom_f_in;
642 io_filesfrom_f_out = -1;
646 FD_SET(io_filesfrom_f_out, &w_fds);
647 new_fd = io_filesfrom_f_out;
653 tv.tv_sec = select_timeout;
658 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
661 if (errno == EBADF) {
662 defer_forwarding_messages = 0;
663 exit_cleanup(RERR_SOCKETIO);
669 if (io_filesfrom_f_out >= 0) {
670 if (io_filesfrom_buflen) {
671 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
672 int l = write(io_filesfrom_f_out,
674 io_filesfrom_buflen);
676 if (!(io_filesfrom_buflen -= l))
677 io_filesfrom_bp = io_filesfrom_buf;
679 io_filesfrom_bp += l;
680 } else if (errno != EINTR) {
681 /* XXX should we complain? */
682 io_filesfrom_f_out = -1;
685 } else if (io_filesfrom_f_in >= 0) {
686 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
687 int l = read(io_filesfrom_f_in,
689 sizeof io_filesfrom_buf);
691 if (l == 0 || errno != EINTR) {
692 /* Send end-of-file marker */
693 io_filesfrom_buf[0] = '\0';
694 io_filesfrom_buf[1] = '\0';
695 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
696 io_filesfrom_f_in = -1;
700 char *s = io_filesfrom_buf + l;
701 /* Transform CR and/or LF into '\0' */
702 while (s-- > io_filesfrom_buf) {
703 if (*s == '\n' || *s == '\r')
707 if (!io_filesfrom_lastchar) {
708 /* Last buf ended with a '\0', so don't
709 * let this buf start with one. */
710 while (l && !*io_filesfrom_bp)
711 io_filesfrom_bp++, l--;
714 io_filesfrom_bp = io_filesfrom_buf;
716 char *f = io_filesfrom_bp;
719 /* Eliminate any multi-'\0' runs. */
721 if (!(*t++ = *f++)) {
722 while (f != eob && !*f)
726 io_filesfrom_lastchar = f[-1];
728 io_filesfrom_buflen = l;
734 if (!FD_ISSET(fd, &r_fds))
737 n = read(fd, buf, len);
741 whine_about_eof(fd); /* Doesn't return. */
742 if (errno == EINTR || errno == EWOULDBLOCK
746 /* Don't write errors on a dead socket. */
747 if (fd == sock_f_in) {
748 io_end_multiplex_out();
749 rsyserr(FSOCKERR, errno, "read error");
751 rsyserr(FERROR, errno, "read error");
752 exit_cleanup(RERR_STREAMIO);
759 if (fd == sock_f_in && io_timeout)
760 last_io_in = time(NULL);
766 /* Read a line into the "fname" buffer (which must be at least MAXPATHLEN
767 * characters long). */
768 int read_filesfrom_line(int fd, char *fname)
770 char ch, *s, *eob = fname + MAXPATHLEN - 1;
772 int reading_remotely = filesfrom_host != NULL;
773 int nulls = eol_nulls || reading_remotely;
778 cnt = read(fd, &ch, 1);
779 if (cnt < 0 && (errno == EWOULDBLOCK
780 || errno == EINTR || errno == EAGAIN)) {
787 tv.tv_sec = select_timeout;
789 if (!select(fd+1, &r_fds, NULL, &e_fds, &tv))
791 if (FD_ISSET(fd, &e_fds)) {
792 rsyserr(FINFO, errno,
793 "select exception on fd %d", fd);
799 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
800 /* Skip empty lines if reading locally. */
801 if (!reading_remotely && s == fname)
811 if (*fname == '#' || *fname == ';')
817 int io_start_buffering_out(int f_out)
820 assert(f_out == iobuf_f_out);
823 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
824 out_of_memory("io_start_buffering_out");
830 int io_start_buffering_in(int f_in)
833 assert(f_in == iobuf_f_in);
836 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
837 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
838 out_of_memory("io_start_buffering_in");
843 void io_end_buffering_in(void)
850 iobuf_in_remaining = 0;
854 void io_end_buffering_out(void)
858 io_flush(FULL_FLUSH);
864 void maybe_flush_socket(int important)
866 if (iobuf_out && iobuf_out_cnt
867 && (important || time(NULL) - last_io_out >= 5))
868 io_flush(NORMAL_FLUSH);
871 void maybe_send_keepalive(void)
873 if (time(NULL) - last_io_out >= allowed_lull) {
874 if (!iobuf_out || !iobuf_out_cnt) {
875 if (protocol_version < 29)
876 return; /* there's nothing we can do */
877 if (protocol_version >= 30)
878 send_msg(MSG_NOOP, "", 0, 0);
880 write_int(sock_f_out, cur_flist->count);
881 write_shortint(sock_f_out, ITEM_IS_NEW);
885 io_flush(NORMAL_FLUSH);
889 void start_flist_forward(int f_in)
891 assert(iobuf_out != NULL);
892 assert(iobuf_f_out == msg_fd_out);
893 flist_forward_from = f_in;
896 void stop_flist_forward()
898 flist_forward_from = -1;
899 io_flush(FULL_FLUSH);
903 * Continue trying to read len bytes - don't return until len has been
906 static void read_loop(int fd, char *buf, size_t len)
909 int n = read_timeout(fd, buf, len);
917 * Read from the file descriptor handling multiplexing - return number
920 * Never returns <= 0.
922 static int readfd_unbuffered(int fd, char *buf, size_t len)
926 char line[BIGPATHBUFLEN];
928 if (!iobuf_in || fd != iobuf_f_in)
929 return read_timeout(fd, buf, len);
931 if (!io_multiplexing_in && iobuf_in_remaining == 0) {
932 iobuf_in_remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
937 if (iobuf_in_remaining) {
938 len = MIN(len, iobuf_in_remaining);
939 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
941 iobuf_in_remaining -= len;
946 read_loop(fd, line, 4);
949 msg_bytes = tag & 0xFFFFFF;
950 tag = (tag >> 24) - MPLEX_BASE;
954 if (msg_bytes > iobuf_in_siz) {
955 if (!(iobuf_in = realloc_array(iobuf_in, char,
957 out_of_memory("readfd_unbuffered");
958 iobuf_in_siz = msg_bytes;
960 read_loop(fd, iobuf_in, msg_bytes);
961 iobuf_in_remaining = msg_bytes;
966 maybe_send_keepalive();
971 read_loop(fd, line, msg_bytes);
972 io_error |= IVAL(line, 0);
975 if (msg_bytes >= sizeof line)
978 if (ic_recv != (iconv_t)-1) {
979 ICONV_CONST char *ibuf;
981 size_t icnt, ocnt = sizeof line - 1;
983 iconv(ic_send, NULL, 0, NULL, 0);
985 icnt = msg_bytes > sizeof iconv_buf
986 ? sizeof iconv_buf : msg_bytes;
987 read_loop(fd, iconv_buf, icnt);
988 if (!(msg_bytes -= icnt) && !iconv_buf[icnt-1])
989 icnt--, add_null = 1;
990 ibuf = (ICONV_CONST char *)iconv_buf;
991 if (iconv(ic_send, &ibuf,&icnt,
992 &obuf,&ocnt) == (size_t)-1)
993 goto overflow; // XXX
997 msg_bytes = obuf - line;
1000 read_loop(fd, line, msg_bytes);
1001 /* A directory name was sent with the trailing null */
1002 if (msg_bytes > 0 && !line[msg_bytes-1])
1003 log_delete(line, S_IFDIR);
1005 line[msg_bytes] = '\0';
1006 log_delete(line, S_IFREG);
1010 if (msg_bytes != 4) {
1012 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
1013 tag, (long)msg_bytes, who_am_i());
1014 exit_cleanup(RERR_STREAMIO);
1016 read_loop(fd, line, msg_bytes);
1017 successful_send(IVAL(line, 0));
1022 read_loop(fd, line, msg_bytes);
1023 send_msg_int(MSG_NO_SEND, IVAL(line, 0));
1027 if (msg_bytes >= sizeof line) {
1030 "multiplexing overflow %d:%ld [%s]\n",
1031 tag, (long)msg_bytes, who_am_i());
1032 exit_cleanup(RERR_STREAMIO);
1034 read_loop(fd, line, msg_bytes);
1035 rwrite((enum logcode)tag, line, msg_bytes, 1);
1038 rprintf(FERROR, "unexpected tag %d [%s]\n",
1040 exit_cleanup(RERR_STREAMIO);
1044 if (iobuf_in_remaining == 0)
1045 io_flush(NORMAL_FLUSH);
1050 /* Do a buffered read from fd. Don't return until all N bytes have
1051 * been read. If all N can't be read then exit with an error. */
1052 static void readfd(int fd, char *buffer, size_t N)
1058 cnt = readfd_unbuffered(fd, buffer + total, N-total);
1062 if (fd == write_batch_monitor_in) {
1063 if ((size_t)write(batch_fd, buffer, total) != total)
1064 exit_cleanup(RERR_FILEIO);
1067 if (fd == flist_forward_from)
1068 writefd(iobuf_f_out, buffer, total);
1070 if (fd == sock_f_in)
1071 stats.total_read += total;
1074 unsigned short read_shortint(int f)
1078 return (UVAL(b, 1) << 8) + UVAL(b, 0);
1081 int32 read_int(int f)
1088 #if SIZEOF_INT32 > 4
1089 if (num & (int32)0x80000000)
1090 num |= ~(int32)0xffffffff;
1095 int32 read_varint(int f)
1105 readfd(f, (char*)&ch, 1);
1106 extra = int_byte_extra[ch / 4];
1108 uchar bit = ((uchar)1<<(8-extra));
1109 if (extra >= (int)sizeof u.b) {
1110 rprintf(FERROR, "Overflow in read_varint()\n");
1111 exit_cleanup(RERR_STREAMIO);
1113 readfd(f, u.b, extra);
1114 u.b[extra] = ch & (bit-1);
1117 #if CAREFUL_ALIGNMENT
1120 #if SIZEOF_INT32 > 4
1121 if (u.x & (int32)0x80000000)
1122 u.x |= ~(int32)0xffffffff;
1127 int64 read_varlong(int f, uchar min_bytes)
1136 #if SIZEOF_INT64 < 8
1141 readfd(f, b2, min_bytes);
1142 memcpy(u.b, b2+1, min_bytes-1);
1143 extra = int_byte_extra[CVAL(b2, 0) / 4];
1145 uchar bit = ((uchar)1<<(8-extra));
1146 if (min_bytes + extra > (int)sizeof u.b) {
1147 rprintf(FERROR, "Overflow in read_varlong()\n");
1148 exit_cleanup(RERR_STREAMIO);
1150 readfd(f, u.b + min_bytes - 1, extra);
1151 u.b[min_bytes + extra - 1] = CVAL(b2, 0) & (bit-1);
1152 #if SIZEOF_INT64 < 8
1153 if (min_bytes + extra > 5 || u.b[4] || CVAL(u.b,3) & 0x80) {
1154 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1155 exit_cleanup(RERR_UNSUPPORTED);
1159 u.b[min_bytes + extra - 1] = CVAL(b2, 0);
1160 #if SIZEOF_INT64 < 8
1162 #elif CAREFUL_ALIGNMENT
1163 u.x = IVAL(u.b,0) | (((int64)IVAL(u.b,4))<<32);
1168 int64 read_longint(int f)
1170 #if SIZEOF_INT64 >= 8
1173 int32 num = read_int(f);
1175 if (num != (int32)0xffffffff)
1178 #if SIZEOF_INT64 < 8
1179 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1180 exit_cleanup(RERR_UNSUPPORTED);
1183 return IVAL(b,0) | (((int64)IVAL(b,4))<<32);
1187 void read_buf(int f, char *buf, size_t len)
1192 void read_sbuf(int f, char *buf, size_t len)
1194 readfd(f, buf, len);
1198 uchar read_byte(int f)
1201 readfd(f, (char *)&c, 1);
1205 int read_vstring(int f, char *buf, int bufsize)
1207 int len = read_byte(f);
1210 len = (len & ~0x80) * 0x100 + read_byte(f);
1212 if (len >= bufsize) {
1213 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
1219 readfd(f, buf, len);
1224 /* Populate a sum_struct with values from the socket. This is
1225 * called by both the sender and the receiver. */
1226 void read_sum_head(int f, struct sum_struct *sum)
1228 sum->count = read_int(f);
1229 if (sum->count < 0) {
1230 rprintf(FERROR, "Invalid checksum count %ld [%s]\n",
1231 (long)sum->count, who_am_i());
1232 exit_cleanup(RERR_PROTOCOL);
1234 sum->blength = read_int(f);
1235 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
1236 rprintf(FERROR, "Invalid block length %ld [%s]\n",
1237 (long)sum->blength, who_am_i());
1238 exit_cleanup(RERR_PROTOCOL);
1240 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
1241 if (sum->s2length < 0 || sum->s2length > MAX_DIGEST_LEN) {
1242 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
1243 sum->s2length, who_am_i());
1244 exit_cleanup(RERR_PROTOCOL);
1246 sum->remainder = read_int(f);
1247 if (sum->remainder < 0 || sum->remainder > sum->blength) {
1248 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
1249 (long)sum->remainder, who_am_i());
1250 exit_cleanup(RERR_PROTOCOL);
1254 /* Send the values from a sum_struct over the socket. Set sum to
1255 * NULL if there are no checksums to send. This is called by both
1256 * the generator and the sender. */
1257 void write_sum_head(int f, struct sum_struct *sum)
1259 static struct sum_struct null_sum;
1264 write_int(f, sum->count);
1265 write_int(f, sum->blength);
1266 if (protocol_version >= 27)
1267 write_int(f, sum->s2length);
1268 write_int(f, sum->remainder);
1272 * Sleep after writing to limit I/O bandwidth usage.
1274 * @todo Rather than sleeping after each write, it might be better to
1275 * use some kind of averaging. The current algorithm seems to always
1276 * use a bit less bandwidth than specified, because it doesn't make up
1277 * for slow periods. But arguably this is a feature. In addition, we
1278 * ought to take the time used to write the data into account.
1280 * During some phases of big transfers (file FOO is uptodate) this is
1281 * called with a small bytes_written every time. As the kernel has to
1282 * round small waits up to guarantee that we actually wait at least the
1283 * requested number of microseconds, this can become grossly inaccurate.
1284 * We therefore keep track of the bytes we've written over time and only
1285 * sleep when the accumulated delay is at least 1 tenth of a second.
1287 static void sleep_for_bwlimit(int bytes_written)
1289 static struct timeval prior_tv;
1290 static long total_written = 0;
1291 struct timeval tv, start_tv;
1292 long elapsed_usec, sleep_usec;
1294 #define ONE_SEC 1000000L /* # of microseconds in a second */
1296 if (!bwlimit_writemax)
1299 total_written += bytes_written;
1301 gettimeofday(&start_tv, NULL);
1302 if (prior_tv.tv_sec) {
1303 elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
1304 + (start_tv.tv_usec - prior_tv.tv_usec);
1305 total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
1306 if (total_written < 0)
1310 sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
1311 if (sleep_usec < ONE_SEC / 10) {
1312 prior_tv = start_tv;
1316 tv.tv_sec = sleep_usec / ONE_SEC;
1317 tv.tv_usec = sleep_usec % ONE_SEC;
1318 select(0, NULL, NULL, NULL, &tv);
1320 gettimeofday(&prior_tv, NULL);
1321 elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
1322 + (prior_tv.tv_usec - start_tv.tv_usec);
1323 total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
1326 /* Write len bytes to the file descriptor fd, looping as necessary to get
1327 * the job done and also (in certain circumstances) reading any data on
1328 * msg_fd_in to avoid deadlock.
1330 * This function underlies the multiplexing system. The body of the
1331 * application never calls this function directly. */
1332 static void writefd_unbuffered(int fd, const char *buf, size_t len)
1334 size_t n, total = 0;
1335 fd_set w_fds, r_fds, e_fds;
1336 int maxfd, count, cnt, using_r_fds;
1341 defer_forwarding_messages++, defer_inc++;
1343 while (total < len) {
1350 if (msg_fd_in >= 0) {
1352 FD_SET(msg_fd_in, &r_fds);
1353 if (msg_fd_in > maxfd)
1359 tv.tv_sec = select_timeout;
1363 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1364 &w_fds, &e_fds, &tv);
1367 if (count < 0 && errno == EBADF)
1368 exit_cleanup(RERR_SOCKETIO);
1373 if (FD_ISSET(fd, &e_fds)) {
1374 rsyserr(FINFO, errno,
1375 "select exception on fd %d", fd);
1378 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1381 if (!FD_ISSET(fd, &w_fds))
1385 if (bwlimit_writemax && n > bwlimit_writemax)
1386 n = bwlimit_writemax;
1387 cnt = write(fd, buf + total, n);
1393 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1399 /* Don't try to write errors back across the stream. */
1400 if (fd == sock_f_out)
1401 io_end_multiplex_out();
1402 /* Don't try to write errors down a failing msg pipe. */
1403 if (am_server && fd == msg_fd_out)
1404 exit_cleanup(RERR_STREAMIO);
1405 rsyserr(FERROR, errno,
1406 "writefd_unbuffered failed to write %ld bytes [%s]",
1407 (long)len, who_am_i());
1408 /* If the other side is sending us error messages, try
1409 * to grab any messages they sent before they died. */
1410 while (fd == sock_f_out && io_multiplexing_in) {
1413 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1414 sizeof io_filesfrom_buf);
1416 exit_cleanup(RERR_STREAMIO);
1420 defer_forwarding_messages++, defer_inc++;
1422 if (fd == sock_f_out) {
1423 if (io_timeout || am_generator)
1424 last_io_out = time(NULL);
1425 sleep_for_bwlimit(cnt);
1430 if (!(defer_forwarding_messages -= defer_inc))
1434 void io_flush(int flush_it_all)
1436 if (!iobuf_out_cnt || no_flush)
1439 if (io_multiplexing_out)
1440 mplex_write(sock_f_out, MSG_DATA, iobuf_out, iobuf_out_cnt, 0);
1442 writefd_unbuffered(iobuf_f_out, iobuf_out, iobuf_out_cnt);
1445 if (flush_it_all && !defer_forwarding_messages)
1449 static void writefd(int fd, const char *buf, size_t len)
1451 if (fd == sock_f_out)
1452 stats.total_written += len;
1454 if (fd == write_batch_monitor_out) {
1455 if ((size_t)write(batch_fd, buf, len) != len)
1456 exit_cleanup(RERR_FILEIO);
1459 if (!iobuf_out || fd != iobuf_f_out) {
1460 writefd_unbuffered(fd, buf, len);
1465 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1467 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1473 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1474 io_flush(NORMAL_FLUSH);
1478 void write_shortint(int f, unsigned short x)
1482 b[1] = (char)(x >> 8);
1486 void write_int(int f, int32 x)
1493 void write_varint(int f, int32 x)
1501 while (cnt > 1 && b[cnt] == 0)
1503 bit = ((uchar)1<<(7-cnt+1));
1504 if (CVAL(b, cnt) >= bit) {
1508 *b = b[cnt] | ~(bit*2-1);
1515 void write_varlong(int f, int64 x, uchar min_bytes)
1522 #if SIZEOF_INT64 >= 8
1523 SIVAL(b, 5, x >> 32);
1525 if (x <= 0x7FFFFFFF && x >= 0)
1526 memset(b + 5, 0, 4);
1528 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1529 exit_cleanup(RERR_UNSUPPORTED);
1533 while (cnt > min_bytes && b[cnt] == 0)
1535 bit = ((uchar)1<<(7-cnt+min_bytes));
1536 if (CVAL(b, cnt) >= bit) {
1539 } else if (cnt > min_bytes)
1540 *b = b[cnt] | ~(bit*2-1);
1548 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1549 * 64-bit types on this platform.
1551 void write_longint(int f, int64 x)
1553 char b[12], * const s = b+4;
1556 if (x <= 0x7FFFFFFF && x >= 0) {
1561 #if SIZEOF_INT64 < 8
1562 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1563 exit_cleanup(RERR_UNSUPPORTED);
1566 SIVAL(s, 4, x >> 32);
1571 void write_buf(int f, const char *buf, size_t len)
1576 /** Write a string to the connection */
1577 void write_sbuf(int f, const char *buf)
1579 writefd(f, buf, strlen(buf));
1582 void write_byte(int f, uchar c)
1584 writefd(f, (char *)&c, 1);
1587 void write_vstring(int f, const char *str, int len)
1589 uchar lenbuf[3], *lb = lenbuf;
1594 "attempting to send over-long vstring (%d > %d)\n",
1596 exit_cleanup(RERR_PROTOCOL);
1598 *lb++ = len / 0x100 + 0x80;
1602 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1604 writefd(f, str, len);
1607 /* Send a file-list index using a byte-reduction method. */
1608 void write_ndx(int f, int32 ndx)
1610 static int32 prev_positive = -1, prev_negative = 1;
1611 int32 diff, cnt = 0;
1614 if (protocol_version < 30 || read_batch) {
1619 /* Send NDX_DONE as a single-byte 0 with no side effects. Send
1620 * negative nums as a positive after sending a leading 0xFF. */
1622 diff = ndx - prev_positive;
1623 prev_positive = ndx;
1624 } else if (ndx == NDX_DONE) {
1629 b[cnt++] = (char)0xFF;
1631 diff = ndx - prev_negative;
1632 prev_negative = ndx;
1635 /* A diff of 1 - 253 is sent as a one-byte diff; a diff of 254 - 32767
1636 * or 0 is sent as a 0xFE + a two-byte diff; otherwise we send 0xFE
1637 * & all 4 bytes of the (non-negative) num with the high-bit set. */
1638 if (diff < 0xFE && diff > 0)
1639 b[cnt++] = (char)diff;
1640 else if (diff < 0 || diff > 0x7FFF) {
1641 b[cnt++] = (char)0xFE;
1642 b[cnt++] = (char)((ndx >> 24) | 0x80);
1643 b[cnt++] = (char)ndx;
1644 b[cnt++] = (char)(ndx >> 8);
1645 b[cnt++] = (char)(ndx >> 16);
1647 b[cnt++] = (char)0xFE;
1648 b[cnt++] = (char)(diff >> 8);
1649 b[cnt++] = (char)diff;
1654 /* Receive a file-list index using a byte-reduction method. */
1655 int32 read_ndx(int f)
1657 static int32 prev_positive = -1, prev_negative = 1;
1658 int32 *prev_ptr, num;
1661 if (protocol_version < 30)
1665 if (CVAL(b, 0) == 0xFF) {
1667 prev_ptr = &prev_negative;
1668 } else if (CVAL(b, 0) == 0)
1671 prev_ptr = &prev_positive;
1672 if (CVAL(b, 0) == 0xFE) {
1674 if (CVAL(b, 0) & 0x80) {
1675 b[3] = CVAL(b, 0) & ~0x80;
1680 num = (UVAL(b,0)<<8) + UVAL(b,1) + *prev_ptr;
1682 num = UVAL(b, 0) + *prev_ptr;
1684 if (prev_ptr == &prev_negative)
1690 * Read a line of up to @p maxlen characters into @p buf (not counting
1691 * the trailing null). Strips the (required) trailing newline and all
1694 * @return 1 for success; 0 for I/O error or truncation.
1696 int read_line(int f, char *buf, size_t maxlen)
1700 read_buf(f, buf, 1);
1705 if (buf[0] != '\r') {
1714 void io_printf(int fd, const char *format, ...)
1717 char buf[BIGPATHBUFLEN];
1720 va_start(ap, format);
1721 len = vsnprintf(buf, sizeof buf, format, ap);
1725 exit_cleanup(RERR_STREAMIO);
1727 if (len > (int)sizeof buf) {
1728 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1729 exit_cleanup(RERR_STREAMIO);
1732 write_sbuf(fd, buf);
1735 /** Setup for multiplexing a MSG_* stream with the data stream. */
1736 void io_start_multiplex_out(void)
1738 io_flush(NORMAL_FLUSH);
1739 io_start_buffering_out(sock_f_out);
1740 io_multiplexing_out = 1;
1743 /** Setup for multiplexing a MSG_* stream with the data stream. */
1744 void io_start_multiplex_in(void)
1746 io_flush(NORMAL_FLUSH);
1747 io_start_buffering_in(sock_f_in);
1748 io_multiplexing_in = 1;
1751 /** Write an message to the multiplexed data stream. */
1752 int io_multiplex_write(enum msgcode code, const char *buf, size_t len, int convert)
1754 if (!io_multiplexing_out)
1756 io_flush(NORMAL_FLUSH);
1757 stats.total_written += (len+4);
1758 mplex_write(sock_f_out, code, buf, len, convert);
1762 void io_end_multiplex_in(void)
1764 io_multiplexing_in = 0;
1765 io_end_buffering_in();
1768 /** Stop output multiplexing. */
1769 void io_end_multiplex_out(void)
1771 io_multiplexing_out = 0;
1772 io_end_buffering_out();
1775 void start_write_batch(int fd)
1777 /* Some communication has already taken place, but we don't
1778 * enable batch writing until here so that we can write a
1779 * canonical record of the communication even though the
1780 * actual communication so far depends on whether a daemon
1782 write_int(batch_fd, protocol_version);
1783 write_int(batch_fd, checksum_seed);
1786 write_batch_monitor_out = fd;
1788 write_batch_monitor_in = fd;
1791 void stop_write_batch(void)
1793 write_batch_monitor_out = -1;
1794 write_batch_monitor_in = -1;