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);
343 flist = recv_file_list(fd);
344 flist->parent_ndx = IVAL(buf,0);
347 if (len != 0 || !am_generator || !inc_recurse)
352 if (len >= (int)sizeof buf || !am_generator)
354 readfd(fd, buf, len);
355 send_msg(MSG_DELETED, buf, len, 1);
358 if (len != 4 || !am_generator)
360 readfd(fd, buf, len);
361 if (remove_source_files) {
362 decrement_active_files(IVAL(buf,0));
363 send_msg(MSG_SUCCESS, buf, len, 0);
365 if (preserve_hard_links)
366 flist_ndx_push(&hlink_list, IVAL(buf,0));
368 decrement_flist_in_progress(IVAL(buf,0), 0);
371 if (len != 4 || !am_generator)
373 readfd(fd, buf, len);
375 decrement_flist_in_progress(IVAL(buf,0), 0);
381 if (tag == MSG_SOCKERR)
382 io_end_multiplex_out();
392 rwrite((enum logcode)tag, buf, n, !am_generator);
397 rprintf(FERROR, "unknown message %d:%d [%s]\n",
398 tag, len, who_am_i());
399 exit_cleanup(RERR_STREAMIO);
404 if (!--defer_forwarding_messages)
408 /* This is used by the generator to limit how many file transfers can
409 * be active at once when --remove-source-files is specified. Without
410 * this, sender-side deletions were mostly happening at the end. */
411 void increment_active_files(int ndx, int itemizing, enum logcode code)
413 /* TODO: tune these limits? */
414 while (active_filecnt >= (active_bytecnt >= 128*1024 ? 10 : 50)) {
415 check_for_finished_files(itemizing, code, 0);
417 io_flush(NORMAL_FLUSH);
423 active_bytecnt += F_LENGTH(cur_flist->files[ndx - cur_flist->ndx_start]);
426 static void decrement_active_files(int ndx)
428 struct file_list *flist = flist_for_ndx(ndx);
429 assert(flist != NULL);
431 active_bytecnt -= F_LENGTH(flist->files[ndx - flist->ndx_start]);
434 static void decrement_flist_in_progress(int ndx, int redo)
436 struct file_list *flist = cur_flist ? cur_flist : first_flist;
438 while (ndx < flist->ndx_start) {
439 if (flist == first_flist) {
442 "Invalid file index: %d (%d - %d) [%s]\n",
443 ndx, first_flist->ndx_start,
444 first_flist->prev->ndx_start + first_flist->prev->count - 1,
446 exit_cleanup(RERR_PROTOCOL);
450 while (ndx >= flist->ndx_start + flist->count) {
451 if (!(flist = flist->next))
455 flist->in_progress--;
460 /* Write an message to a multiplexed stream. If this fails, rsync exits. */
461 static void mplex_write(int fd, enum msgcode code, const char *buf, size_t len, int convert)
463 char buffer[BIGPATHBUFLEN]; /* Oversized for use by iconv code. */
466 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
469 if (convert && ic_send == (iconv_t)-1)
473 if (convert || n > 1024 - 4) /* BIGPATHBUFLEN can handle 1024 bytes */
476 memcpy(buffer + 4, buf, n);
478 writefd_unbuffered(fd, buffer, n+4);
485 iconv(ic_send, NULL, 0, NULL, 0);
486 defer_forwarding_messages++;
488 ICONV_CONST char *ibuf = (ICONV_CONST char *)buf;
490 size_t ocnt = sizeof buffer;
491 while (len && iconv(ic_send, &ibuf,&len,
492 &obuf,&ocnt) == (size_t)-1) {
493 if (errno == E2BIG || !ocnt)
499 writefd_unbuffered(fd, buffer, n);
501 if (!--defer_forwarding_messages)
506 defer_forwarding_messages++;
507 writefd_unbuffered(fd, buf, len);
508 if (!--defer_forwarding_messages)
513 int send_msg(enum msgcode code, const char *buf, int len, int convert)
515 if (msg_fd_out < 0) {
516 if (!defer_forwarding_messages)
517 return io_multiplex_write(code, buf, len, convert);
518 if (!io_multiplexing_out)
520 msg_list_add(&msg_queue, code, buf, len, convert);
523 if (flist_forward_from >= 0)
524 msg_list_add(&msg_queue, code, buf, len, convert);
526 mplex_write(msg_fd_out, code, buf, len, convert);
530 void send_msg_int(enum msgcode code, int num)
533 SIVAL(numbuf, 0, num);
534 send_msg(code, numbuf, 4, 0);
537 void wait_for_receiver(void)
540 io_flush(NORMAL_FLUSH);
545 int get_redo_num(void)
547 return flist_ndx_pop(&redo_list);
550 int get_hlink_num(void)
552 return flist_ndx_pop(&hlink_list);
556 * When we're the receiver and we have a local --files-from list of names
557 * that needs to be sent over the socket to the sender, we have to do two
558 * things at the same time: send the sender a list of what files we're
559 * processing and read the incoming file+info list from the sender. We do
560 * this by augmenting the read_timeout() function to copy this data. It
561 * uses the io_filesfrom_buf to read a block of data from f_in (when it is
562 * ready, since it might be a pipe) and then blast it out f_out (when it
563 * is ready to receive more data).
565 void io_set_filesfrom_fds(int f_in, int f_out)
567 io_filesfrom_f_in = f_in;
568 io_filesfrom_f_out = f_out;
569 io_filesfrom_bp = io_filesfrom_buf;
570 io_filesfrom_lastchar = '\0';
571 io_filesfrom_buflen = 0;
574 /* It's almost always an error to get an EOF when we're trying to read from the
575 * network, because the protocol is (for the most part) self-terminating.
577 * There is one case for the receiver when it is at the end of the transfer
578 * (hanging around reading any keep-alive packets that might come its way): if
579 * the sender dies before the generator's kill-signal comes through, we can end
580 * up here needing to loop until the kill-signal arrives. In this situation,
581 * kluge_around_eof will be < 0.
583 * There is another case for older protocol versions (< 24) where the module
584 * listing was not terminated, so we must ignore an EOF error in that case and
585 * exit. In this situation, kluge_around_eof will be > 0. */
586 static void whine_about_eof(int fd)
588 if (kluge_around_eof && fd == sock_f_in) {
590 if (kluge_around_eof > 0)
592 /* If we're still here after 10 seconds, exit with an error. */
593 for (i = 10*1000/20; i--; )
597 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
598 "(%.0f bytes received so far) [%s]\n",
599 (double)stats.total_read, who_am_i());
601 exit_cleanup(RERR_STREAMIO);
605 * Read from a socket with I/O timeout. return the number of bytes
606 * read. If no bytes can be read then exit, never return a number <= 0.
608 * TODO: If the remote shell connection fails, then current versions
609 * actually report an "unexpected EOF" error here. Since it's a
610 * fairly common mistake to try to use rsh when ssh is required, we
611 * should trap that: if we fail to read any data at all, we should
612 * give a better explanation. We can tell whether the connection has
613 * started by looking e.g. at whether the remote version is known yet.
615 static int read_timeout(int fd, char *buf, size_t len)
619 io_flush(FULL_FLUSH);
622 /* until we manage to read *something* */
631 if (io_filesfrom_f_out >= 0) {
633 if (io_filesfrom_buflen == 0) {
634 if (io_filesfrom_f_in >= 0) {
635 FD_SET(io_filesfrom_f_in, &r_fds);
636 new_fd = io_filesfrom_f_in;
638 io_filesfrom_f_out = -1;
642 FD_SET(io_filesfrom_f_out, &w_fds);
643 new_fd = io_filesfrom_f_out;
649 tv.tv_sec = select_timeout;
654 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
657 if (errno == EBADF) {
658 defer_forwarding_messages = 0;
659 exit_cleanup(RERR_SOCKETIO);
665 if (io_filesfrom_f_out >= 0) {
666 if (io_filesfrom_buflen) {
667 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
668 int l = write(io_filesfrom_f_out,
670 io_filesfrom_buflen);
672 if (!(io_filesfrom_buflen -= l))
673 io_filesfrom_bp = io_filesfrom_buf;
675 io_filesfrom_bp += l;
677 /* XXX should we complain? */
678 io_filesfrom_f_out = -1;
681 } else if (io_filesfrom_f_in >= 0) {
682 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
683 int l = read(io_filesfrom_f_in,
685 sizeof io_filesfrom_buf);
687 /* Send end-of-file marker */
688 io_filesfrom_buf[0] = '\0';
689 io_filesfrom_buf[1] = '\0';
690 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
691 io_filesfrom_f_in = -1;
694 char *s = io_filesfrom_buf + l;
695 /* Transform CR and/or LF into '\0' */
696 while (s-- > io_filesfrom_buf) {
697 if (*s == '\n' || *s == '\r')
701 if (!io_filesfrom_lastchar) {
702 /* Last buf ended with a '\0', so don't
703 * let this buf start with one. */
704 while (l && !*io_filesfrom_bp)
705 io_filesfrom_bp++, l--;
708 io_filesfrom_bp = io_filesfrom_buf;
710 char *f = io_filesfrom_bp;
713 /* Eliminate any multi-'\0' runs. */
715 if (!(*t++ = *f++)) {
716 while (f != eob && !*f)
720 io_filesfrom_lastchar = f[-1];
722 io_filesfrom_buflen = l;
728 if (!FD_ISSET(fd, &r_fds))
731 n = read(fd, buf, len);
735 whine_about_eof(fd); /* Doesn't return. */
736 if (errno == EINTR || errno == EWOULDBLOCK
740 /* Don't write errors on a dead socket. */
741 if (fd == sock_f_in) {
742 io_end_multiplex_out();
743 rsyserr(FSOCKERR, errno, "read error");
745 rsyserr(FERROR, errno, "read error");
746 exit_cleanup(RERR_STREAMIO);
753 if (fd == sock_f_in && io_timeout)
754 last_io_in = time(NULL);
760 /* Read a line into the "fname" buffer (which must be at least MAXPATHLEN
761 * characters long). */
762 int read_filesfrom_line(int fd, char *fname)
764 char ch, *s, *eob = fname + MAXPATHLEN - 1;
766 int reading_remotely = filesfrom_host != NULL;
767 int nulls = eol_nulls || reading_remotely;
772 cnt = read(fd, &ch, 1);
773 if (cnt < 0 && (errno == EWOULDBLOCK
774 || errno == EINTR || errno == EAGAIN)) {
781 tv.tv_sec = select_timeout;
783 if (!select(fd+1, &r_fds, NULL, &e_fds, &tv))
785 if (FD_ISSET(fd, &e_fds)) {
786 rsyserr(FINFO, errno,
787 "select exception on fd %d", fd);
793 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
794 /* Skip empty lines if reading locally. */
795 if (!reading_remotely && s == fname)
805 if (*fname == '#' || *fname == ';')
811 int io_start_buffering_out(int f_out)
814 assert(f_out == iobuf_f_out);
817 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
818 out_of_memory("io_start_buffering_out");
824 int io_start_buffering_in(int f_in)
827 assert(f_in == iobuf_f_in);
830 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
831 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
832 out_of_memory("io_start_buffering_in");
837 void io_end_buffering_in(void)
844 iobuf_in_remaining = 0;
848 void io_end_buffering_out(void)
852 io_flush(FULL_FLUSH);
858 void maybe_flush_socket(int important)
860 if (iobuf_out && iobuf_out_cnt
861 && (important || time(NULL) - last_io_out >= 5))
862 io_flush(NORMAL_FLUSH);
865 void maybe_send_keepalive(void)
867 if (time(NULL) - last_io_out >= allowed_lull) {
868 if (!iobuf_out || !iobuf_out_cnt) {
869 if (protocol_version < 29)
870 return; /* there's nothing we can do */
871 if (protocol_version >= 30)
872 send_msg(MSG_NOOP, "", 0, 0);
874 write_int(sock_f_out, cur_flist->count);
875 write_shortint(sock_f_out, ITEM_IS_NEW);
879 io_flush(NORMAL_FLUSH);
883 void start_flist_forward(int f_in)
885 assert(iobuf_out != NULL);
886 assert(iobuf_f_out == msg_fd_out);
887 flist_forward_from = f_in;
890 void stop_flist_forward()
892 flist_forward_from = -1;
893 io_flush(FULL_FLUSH);
897 * Continue trying to read len bytes - don't return until len has been
900 static void read_loop(int fd, char *buf, size_t len)
903 int n = read_timeout(fd, buf, len);
911 * Read from the file descriptor handling multiplexing - return number
914 * Never returns <= 0.
916 static int readfd_unbuffered(int fd, char *buf, size_t len)
920 char line[BIGPATHBUFLEN];
922 if (!iobuf_in || fd != iobuf_f_in)
923 return read_timeout(fd, buf, len);
925 if (!io_multiplexing_in && iobuf_in_remaining == 0) {
926 iobuf_in_remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
931 if (iobuf_in_remaining) {
932 len = MIN(len, iobuf_in_remaining);
933 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
935 iobuf_in_remaining -= len;
940 read_loop(fd, line, 4);
943 msg_bytes = tag & 0xFFFFFF;
944 tag = (tag >> 24) - MPLEX_BASE;
948 if (msg_bytes > iobuf_in_siz) {
949 if (!(iobuf_in = realloc_array(iobuf_in, char,
951 out_of_memory("readfd_unbuffered");
952 iobuf_in_siz = msg_bytes;
954 read_loop(fd, iobuf_in, msg_bytes);
955 iobuf_in_remaining = msg_bytes;
960 maybe_send_keepalive();
965 read_loop(fd, line, msg_bytes);
966 io_error |= IVAL(line, 0);
969 if (msg_bytes >= sizeof line)
972 if (ic_recv != (iconv_t)-1) {
973 ICONV_CONST char *ibuf;
975 size_t icnt, ocnt = sizeof line - 1;
977 iconv(ic_send, NULL, 0, NULL, 0);
979 icnt = msg_bytes > sizeof iconv_buf
980 ? sizeof iconv_buf : msg_bytes;
981 read_loop(fd, iconv_buf, icnt);
982 if (!(msg_bytes -= icnt) && !iconv_buf[icnt-1])
983 icnt--, add_null = 1;
984 ibuf = (ICONV_CONST char *)iconv_buf;
985 if (iconv(ic_send, &ibuf,&icnt,
986 &obuf,&ocnt) == (size_t)-1)
987 goto overflow; // XXX
991 msg_bytes = obuf - line;
994 read_loop(fd, line, msg_bytes);
995 /* A directory name was sent with the trailing null */
996 if (msg_bytes > 0 && !line[msg_bytes-1])
997 log_delete(line, S_IFDIR);
999 line[msg_bytes] = '\0';
1000 log_delete(line, S_IFREG);
1004 if (msg_bytes != 4) {
1006 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
1007 tag, (long)msg_bytes, who_am_i());
1008 exit_cleanup(RERR_STREAMIO);
1010 read_loop(fd, line, msg_bytes);
1011 successful_send(IVAL(line, 0));
1016 read_loop(fd, line, msg_bytes);
1017 send_msg_int(MSG_NO_SEND, IVAL(line, 0));
1021 if (msg_bytes >= sizeof line) {
1024 "multiplexing overflow %d:%ld [%s]\n",
1025 tag, (long)msg_bytes, who_am_i());
1026 exit_cleanup(RERR_STREAMIO);
1028 read_loop(fd, line, msg_bytes);
1029 rwrite((enum logcode)tag, line, msg_bytes, 1);
1032 rprintf(FERROR, "unexpected tag %d [%s]\n",
1034 exit_cleanup(RERR_STREAMIO);
1038 if (iobuf_in_remaining == 0)
1039 io_flush(NORMAL_FLUSH);
1044 /* Do a buffered read from fd. Don't return until all N bytes have
1045 * been read. If all N can't be read then exit with an error. */
1046 static void readfd(int fd, char *buffer, size_t N)
1052 cnt = readfd_unbuffered(fd, buffer + total, N-total);
1056 if (fd == write_batch_monitor_in) {
1057 if ((size_t)write(batch_fd, buffer, total) != total)
1058 exit_cleanup(RERR_FILEIO);
1061 if (fd == flist_forward_from)
1062 writefd(iobuf_f_out, buffer, total);
1064 if (fd == sock_f_in)
1065 stats.total_read += total;
1068 unsigned short read_shortint(int f)
1072 return (UVAL(b, 1) << 8) + UVAL(b, 0);
1075 int32 read_int(int f)
1082 #if SIZEOF_INT32 > 4
1083 if (num & (int32)0x80000000)
1084 num |= ~(int32)0xffffffff;
1089 int32 read_varint(int f)
1099 readfd(f, (char*)&ch, 1);
1100 extra = int_byte_extra[ch / 4];
1102 uchar bit = ((uchar)1<<(8-extra));
1103 if (extra >= (int)sizeof u.b) {
1104 rprintf(FERROR, "Overflow in read_varint()\n");
1105 exit_cleanup(RERR_STREAMIO);
1107 readfd(f, u.b, extra);
1108 u.b[extra] = ch & (bit-1);
1111 #if CAREFUL_ALIGNMENT
1114 #if SIZEOF_INT32 > 4
1115 if (u.x & (int32)0x80000000)
1116 u.x |= ~(int32)0xffffffff;
1121 int64 read_varlong(int f, uchar min_bytes)
1130 #if SIZEOF_INT64 < 8
1135 readfd(f, b2, min_bytes);
1136 memcpy(u.b, b2+1, min_bytes-1);
1137 extra = int_byte_extra[CVAL(b2, 0) / 4];
1139 uchar bit = ((uchar)1<<(8-extra));
1140 if (min_bytes + extra > (int)sizeof u.b) {
1141 rprintf(FERROR, "Overflow in read_varlong()\n");
1142 exit_cleanup(RERR_STREAMIO);
1144 readfd(f, u.b + min_bytes - 1, extra);
1145 u.b[min_bytes + extra - 1] = CVAL(b2, 0) & (bit-1);
1146 #if SIZEOF_INT64 < 8
1147 if (min_bytes + extra > 5 || u.b[4] || CVAL(u.b,3) & 0x80) {
1148 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1149 exit_cleanup(RERR_UNSUPPORTED);
1153 u.b[min_bytes + extra - 1] = CVAL(b2, 0);
1154 #if SIZEOF_INT64 < 8
1156 #elif CAREFUL_ALIGNMENT
1157 u.x = IVAL(u.b,0) | (((int64)IVAL(u.b,4))<<32);
1162 int64 read_longint(int f)
1164 #if SIZEOF_INT64 >= 8
1167 int32 num = read_int(f);
1169 if (num != (int32)0xffffffff)
1172 #if SIZEOF_INT64 < 8
1173 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1174 exit_cleanup(RERR_UNSUPPORTED);
1177 return IVAL(b,0) | (((int64)IVAL(b,4))<<32);
1181 void read_buf(int f, char *buf, size_t len)
1186 void read_sbuf(int f, char *buf, size_t len)
1188 readfd(f, buf, len);
1192 uchar read_byte(int f)
1195 readfd(f, (char *)&c, 1);
1199 int read_vstring(int f, char *buf, int bufsize)
1201 int len = read_byte(f);
1204 len = (len & ~0x80) * 0x100 + read_byte(f);
1206 if (len >= bufsize) {
1207 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
1213 readfd(f, buf, len);
1218 /* Populate a sum_struct with values from the socket. This is
1219 * called by both the sender and the receiver. */
1220 void read_sum_head(int f, struct sum_struct *sum)
1222 sum->count = read_int(f);
1223 if (sum->count < 0) {
1224 rprintf(FERROR, "Invalid checksum count %ld [%s]\n",
1225 (long)sum->count, who_am_i());
1226 exit_cleanup(RERR_PROTOCOL);
1228 sum->blength = read_int(f);
1229 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
1230 rprintf(FERROR, "Invalid block length %ld [%s]\n",
1231 (long)sum->blength, who_am_i());
1232 exit_cleanup(RERR_PROTOCOL);
1234 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
1235 if (sum->s2length < 0 || sum->s2length > MAX_DIGEST_LEN) {
1236 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
1237 sum->s2length, who_am_i());
1238 exit_cleanup(RERR_PROTOCOL);
1240 sum->remainder = read_int(f);
1241 if (sum->remainder < 0 || sum->remainder > sum->blength) {
1242 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
1243 (long)sum->remainder, who_am_i());
1244 exit_cleanup(RERR_PROTOCOL);
1248 /* Send the values from a sum_struct over the socket. Set sum to
1249 * NULL if there are no checksums to send. This is called by both
1250 * the generator and the sender. */
1251 void write_sum_head(int f, struct sum_struct *sum)
1253 static struct sum_struct null_sum;
1258 write_int(f, sum->count);
1259 write_int(f, sum->blength);
1260 if (protocol_version >= 27)
1261 write_int(f, sum->s2length);
1262 write_int(f, sum->remainder);
1266 * Sleep after writing to limit I/O bandwidth usage.
1268 * @todo Rather than sleeping after each write, it might be better to
1269 * use some kind of averaging. The current algorithm seems to always
1270 * use a bit less bandwidth than specified, because it doesn't make up
1271 * for slow periods. But arguably this is a feature. In addition, we
1272 * ought to take the time used to write the data into account.
1274 * During some phases of big transfers (file FOO is uptodate) this is
1275 * called with a small bytes_written every time. As the kernel has to
1276 * round small waits up to guarantee that we actually wait at least the
1277 * requested number of microseconds, this can become grossly inaccurate.
1278 * We therefore keep track of the bytes we've written over time and only
1279 * sleep when the accumulated delay is at least 1 tenth of a second.
1281 static void sleep_for_bwlimit(int bytes_written)
1283 static struct timeval prior_tv;
1284 static long total_written = 0;
1285 struct timeval tv, start_tv;
1286 long elapsed_usec, sleep_usec;
1288 #define ONE_SEC 1000000L /* # of microseconds in a second */
1290 if (!bwlimit_writemax)
1293 total_written += bytes_written;
1295 gettimeofday(&start_tv, NULL);
1296 if (prior_tv.tv_sec) {
1297 elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
1298 + (start_tv.tv_usec - prior_tv.tv_usec);
1299 total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
1300 if (total_written < 0)
1304 sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
1305 if (sleep_usec < ONE_SEC / 10) {
1306 prior_tv = start_tv;
1310 tv.tv_sec = sleep_usec / ONE_SEC;
1311 tv.tv_usec = sleep_usec % ONE_SEC;
1312 select(0, NULL, NULL, NULL, &tv);
1314 gettimeofday(&prior_tv, NULL);
1315 elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
1316 + (prior_tv.tv_usec - start_tv.tv_usec);
1317 total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
1320 /* Write len bytes to the file descriptor fd, looping as necessary to get
1321 * the job done and also (in certain circumstances) reading any data on
1322 * msg_fd_in to avoid deadlock.
1324 * This function underlies the multiplexing system. The body of the
1325 * application never calls this function directly. */
1326 static void writefd_unbuffered(int fd, const char *buf, size_t len)
1328 size_t n, total = 0;
1329 fd_set w_fds, r_fds, e_fds;
1330 int maxfd, count, cnt, using_r_fds;
1335 defer_forwarding_messages++, defer_inc++;
1337 while (total < len) {
1344 if (msg_fd_in >= 0) {
1346 FD_SET(msg_fd_in, &r_fds);
1347 if (msg_fd_in > maxfd)
1353 tv.tv_sec = select_timeout;
1357 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1358 &w_fds, &e_fds, &tv);
1361 if (count < 0 && errno == EBADF)
1362 exit_cleanup(RERR_SOCKETIO);
1367 if (FD_ISSET(fd, &e_fds)) {
1368 rsyserr(FINFO, errno,
1369 "select exception on fd %d", fd);
1372 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1375 if (!FD_ISSET(fd, &w_fds))
1379 if (bwlimit_writemax && n > bwlimit_writemax)
1380 n = bwlimit_writemax;
1381 cnt = write(fd, buf + total, n);
1387 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1393 /* Don't try to write errors back across the stream. */
1394 if (fd == sock_f_out)
1395 io_end_multiplex_out();
1396 /* Don't try to write errors down a failing msg pipe. */
1397 if (am_server && fd == msg_fd_out)
1398 exit_cleanup(RERR_STREAMIO);
1399 rsyserr(FERROR, errno,
1400 "writefd_unbuffered failed to write %ld bytes [%s]",
1401 (long)len, who_am_i());
1402 /* If the other side is sending us error messages, try
1403 * to grab any messages they sent before they died. */
1404 while (fd == sock_f_out && io_multiplexing_in) {
1407 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1408 sizeof io_filesfrom_buf);
1410 exit_cleanup(RERR_STREAMIO);
1414 defer_forwarding_messages++, defer_inc++;
1416 if (fd == sock_f_out) {
1417 if (io_timeout || am_generator)
1418 last_io_out = time(NULL);
1419 sleep_for_bwlimit(cnt);
1424 if (!(defer_forwarding_messages -= defer_inc))
1428 void io_flush(int flush_it_all)
1430 if (!iobuf_out_cnt || no_flush)
1433 if (io_multiplexing_out)
1434 mplex_write(sock_f_out, MSG_DATA, iobuf_out, iobuf_out_cnt, 0);
1436 writefd_unbuffered(iobuf_f_out, iobuf_out, iobuf_out_cnt);
1439 if (flush_it_all && !defer_forwarding_messages)
1443 static void writefd(int fd, const char *buf, size_t len)
1445 if (fd == sock_f_out)
1446 stats.total_written += len;
1448 if (fd == write_batch_monitor_out) {
1449 if ((size_t)write(batch_fd, buf, len) != len)
1450 exit_cleanup(RERR_FILEIO);
1453 if (!iobuf_out || fd != iobuf_f_out) {
1454 writefd_unbuffered(fd, buf, len);
1459 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1461 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1467 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1468 io_flush(NORMAL_FLUSH);
1472 void write_shortint(int f, unsigned short x)
1476 b[1] = (char)(x >> 8);
1480 void write_int(int f, int32 x)
1487 void write_varint(int f, int32 x)
1495 while (cnt > 1 && b[cnt] == 0)
1497 bit = ((uchar)1<<(7-cnt+1));
1498 if (CVAL(b, cnt) >= bit) {
1502 *b = b[cnt] | ~(bit*2-1);
1509 void write_varlong(int f, int64 x, uchar min_bytes)
1516 #if SIZEOF_INT64 >= 8
1517 SIVAL(b, 5, x >> 32);
1519 if (x <= 0x7FFFFFFF && x >= 0)
1520 memset(b + 5, 0, 4);
1522 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1523 exit_cleanup(RERR_UNSUPPORTED);
1527 while (cnt > min_bytes && b[cnt] == 0)
1529 bit = ((uchar)1<<(7-cnt+min_bytes));
1530 if (CVAL(b, cnt) >= bit) {
1533 } else if (cnt > min_bytes)
1534 *b = b[cnt] | ~(bit*2-1);
1542 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1543 * 64-bit types on this platform.
1545 void write_longint(int f, int64 x)
1547 char b[12], * const s = b+4;
1550 if (x <= 0x7FFFFFFF && x >= 0) {
1555 #if SIZEOF_INT64 < 8
1556 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1557 exit_cleanup(RERR_UNSUPPORTED);
1560 SIVAL(s, 4, x >> 32);
1565 void write_buf(int f, const char *buf, size_t len)
1570 /** Write a string to the connection */
1571 void write_sbuf(int f, const char *buf)
1573 writefd(f, buf, strlen(buf));
1576 void write_byte(int f, uchar c)
1578 writefd(f, (char *)&c, 1);
1581 void write_vstring(int f, const char *str, int len)
1583 uchar lenbuf[3], *lb = lenbuf;
1588 "attempting to send over-long vstring (%d > %d)\n",
1590 exit_cleanup(RERR_PROTOCOL);
1592 *lb++ = len / 0x100 + 0x80;
1596 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1598 writefd(f, str, len);
1601 /* Send a file-list index using a byte-reduction method. */
1602 void write_ndx(int f, int32 ndx)
1604 static int32 prev_positive = -1, prev_negative = 1;
1605 int32 diff, cnt = 0;
1608 if (protocol_version < 30 || read_batch) {
1613 /* Send NDX_DONE as a single-byte 0 with no side effects. Send
1614 * negative nums as a positive after sending a leading 0xFF. */
1616 diff = ndx - prev_positive;
1617 prev_positive = ndx;
1618 } else if (ndx == NDX_DONE) {
1623 b[cnt++] = (char)0xFF;
1625 diff = ndx - prev_negative;
1626 prev_negative = ndx;
1629 /* A diff of 1 - 253 is sent as a one-byte diff; a diff of 254 - 32767
1630 * or 0 is sent as a 0xFE + a two-byte diff; otherwise we send 0xFE
1631 * & all 4 bytes of the (non-negative) num with the high-bit set. */
1632 if (diff < 0xFE && diff > 0)
1633 b[cnt++] = (char)diff;
1634 else if (diff < 0 || diff > 0x7FFF) {
1635 b[cnt++] = (char)0xFE;
1636 b[cnt++] = (char)((ndx >> 24) | 0x80);
1637 b[cnt++] = (char)ndx;
1638 b[cnt++] = (char)(ndx >> 8);
1639 b[cnt++] = (char)(ndx >> 16);
1641 b[cnt++] = (char)0xFE;
1642 b[cnt++] = (char)(diff >> 8);
1643 b[cnt++] = (char)diff;
1648 /* Receive a file-list index using a byte-reduction method. */
1649 int32 read_ndx(int f)
1651 static int32 prev_positive = -1, prev_negative = 1;
1652 int32 *prev_ptr, num;
1655 if (protocol_version < 30)
1659 if (CVAL(b, 0) == 0xFF) {
1661 prev_ptr = &prev_negative;
1662 } else if (CVAL(b, 0) == 0)
1665 prev_ptr = &prev_positive;
1666 if (CVAL(b, 0) == 0xFE) {
1668 if (CVAL(b, 0) & 0x80) {
1669 b[3] = CVAL(b, 0) & ~0x80;
1674 num = (UVAL(b,0)<<8) + UVAL(b,1) + *prev_ptr;
1676 num = UVAL(b, 0) + *prev_ptr;
1678 if (prev_ptr == &prev_negative)
1684 * Read a line of up to @p maxlen characters into @p buf (not counting
1685 * the trailing null). Strips the (required) trailing newline and all
1688 * @return 1 for success; 0 for I/O error or truncation.
1690 int read_line(int f, char *buf, size_t maxlen)
1694 read_buf(f, buf, 1);
1699 if (buf[0] != '\r') {
1708 void io_printf(int fd, const char *format, ...)
1711 char buf[BIGPATHBUFLEN];
1714 va_start(ap, format);
1715 len = vsnprintf(buf, sizeof buf, format, ap);
1719 exit_cleanup(RERR_STREAMIO);
1721 if (len > (int)sizeof buf) {
1722 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1723 exit_cleanup(RERR_STREAMIO);
1726 write_sbuf(fd, buf);
1729 /** Setup for multiplexing a MSG_* stream with the data stream. */
1730 void io_start_multiplex_out(void)
1732 io_flush(NORMAL_FLUSH);
1733 io_start_buffering_out(sock_f_out);
1734 io_multiplexing_out = 1;
1737 /** Setup for multiplexing a MSG_* stream with the data stream. */
1738 void io_start_multiplex_in(void)
1740 io_flush(NORMAL_FLUSH);
1741 io_start_buffering_in(sock_f_in);
1742 io_multiplexing_in = 1;
1745 /** Write an message to the multiplexed data stream. */
1746 int io_multiplex_write(enum msgcode code, const char *buf, size_t len, int convert)
1748 if (!io_multiplexing_out)
1750 io_flush(NORMAL_FLUSH);
1751 stats.total_written += (len+4);
1752 mplex_write(sock_f_out, code, buf, len, convert);
1756 void io_end_multiplex_in(void)
1758 io_multiplexing_in = 0;
1759 io_end_buffering_in();
1762 /** Stop output multiplexing. */
1763 void io_end_multiplex_out(void)
1765 io_multiplexing_out = 0;
1766 io_end_buffering_out();
1769 void start_write_batch(int fd)
1771 /* Some communication has already taken place, but we don't
1772 * enable batch writing until here so that we can write a
1773 * canonical record of the communication even though the
1774 * actual communication so far depends on whether a daemon
1776 write_int(batch_fd, protocol_version);
1777 write_int(batch_fd, checksum_seed);
1780 write_batch_monitor_out = fd;
1782 write_batch_monitor_in = fd;
1785 void stop_write_batch(void)
1787 write_batch_monitor_out = -1;
1788 write_batch_monitor_in = -1;