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, 2004, 2005, 2006 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 as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
24 /* Rsync provides its own multiplexing system, which is used to send
25 * stderr and stdout over a single socket.
27 * For historical reasons this is off during the start of the
28 * connection, but it's switched on quite early using
29 * io_start_multiplex_out() and io_start_multiplex_in(). */
33 /** If no timeout is specified then use a 60 second select timeout */
34 #define SELECT_TIMEOUT 60
37 extern size_t bwlimit_writemax;
38 extern int io_timeout;
39 extern int allowed_lull;
43 extern int am_generator;
45 extern int read_batch;
46 extern int csum_length;
47 extern int checksum_seed;
48 extern int protocol_version;
49 extern int remove_source_files;
50 extern int preserve_hard_links;
51 extern char *filesfrom_host;
52 extern struct stats stats;
53 extern struct file_list *the_file_list;
55 const char phase_unknown[] = "unknown";
56 int ignore_timeout = 0;
58 int batch_gen_fd = -1;
60 /* Ignore an EOF error if non-zero. See whine_about_eof(). */
61 int kluge_around_eof = 0;
68 static int io_multiplexing_out;
69 static int io_multiplexing_in;
70 static time_t last_io_in;
71 static time_t last_io_out;
74 static int write_batch_monitor_in = -1;
75 static int write_batch_monitor_out = -1;
77 static int io_filesfrom_f_in = -1;
78 static int io_filesfrom_f_out = -1;
79 static char io_filesfrom_buf[2048];
80 static char *io_filesfrom_bp;
81 static char io_filesfrom_lastchar;
82 static int io_filesfrom_buflen;
83 static int defer_forwarding_messages = 0;
84 static int select_timeout = SELECT_TIMEOUT;
85 static int active_filecnt = 0;
86 static OFF_T active_bytecnt = 0;
88 static char int_byte_cnt[256] = {
89 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 00 - 0F */
90 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 10 - 1F */
91 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 20 - 2F */
92 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 30 - 3F */
93 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 40 - 4F */
94 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 50 - 5F */
95 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 60 - 6F */
96 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 70 - 7F */
97 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, /* 80 - 8F */
98 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, /* 90 - 9F */
99 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, /* A0 - AF */
100 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, /* B0 - BF */
101 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, /* C0 - CF */
102 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, /* D0 - DF */
103 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, /* E0 - EF */
104 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, /* F0 - FF */
107 static void read_loop(int fd, char *buf, size_t len);
109 struct flist_ndx_item {
110 struct flist_ndx_item *next;
114 struct flist_ndx_list {
115 struct flist_ndx_item *head, *tail;
118 static struct flist_ndx_list redo_list, hlink_list;
120 struct msg_list_item {
121 struct msg_list_item *next;
127 struct msg_list_item *head, *tail;
130 static struct msg_list msg2genr, msg2sndr;
132 static void flist_ndx_push(struct flist_ndx_list *lp, int ndx)
134 struct flist_ndx_item *item;
136 if (!(item = new(struct flist_ndx_item)))
137 out_of_memory("flist_ndx_push");
141 lp->tail->next = item;
147 static int flist_ndx_pop(struct flist_ndx_list *lp)
149 struct flist_ndx_item *next;
156 next = lp->head->next;
165 static void check_timeout(void)
169 if (!io_timeout || ignore_timeout)
173 last_io_in = time(NULL);
179 if (t - last_io_in >= io_timeout) {
180 if (!am_server && !am_daemon) {
181 rprintf(FERROR, "io timeout after %d seconds -- exiting\n",
182 (int)(t-last_io_in));
184 exit_cleanup(RERR_TIMEOUT);
188 /* Note the fds used for the main socket (which might really be a pipe
189 * for a local transfer, but we can ignore that). */
190 void io_set_sock_fds(int f_in, int f_out)
196 void set_io_timeout(int secs)
200 if (!io_timeout || io_timeout > SELECT_TIMEOUT)
201 select_timeout = SELECT_TIMEOUT;
203 select_timeout = io_timeout;
205 allowed_lull = read_batch ? 0 : (io_timeout + 1) / 2;
208 /* Setup the fd used to receive MSG_* messages. Only needed during the
209 * early stages of being a local sender (up through the sending of the
210 * file list) or when we're the generator (to fetch the messages from
212 void set_msg_fd_in(int fd)
217 /* Setup the fd used to send our MSG_* messages. Only needed when
218 * we're the receiver (to send our messages to the generator). */
219 void set_msg_fd_out(int fd)
222 set_nonblocking(msg_fd_out);
225 /* Add a message to the pending MSG_* list. */
226 static void msg_list_add(struct msg_list *lst, int code, const char *buf, int len)
228 struct msg_list_item *m;
229 int sz = len + 4 + sizeof m[0] - 1;
231 if (!(m = (struct msg_list_item *)new_array(char, sz)))
232 out_of_memory("msg_list_add");
235 SIVAL(m->buf, 0, ((code+MPLEX_BASE)<<24) | len);
236 memcpy(m->buf + 4, buf, len);
244 /* Read a message from the MSG_* fd and handle it. This is called either
245 * during the early stages of being a local sender (up through the sending
246 * of the file list) or when we're the generator (to fetch the messages
247 * from the receiver). */
248 static void read_msg_fd(void)
255 /* Temporarily disable msg_fd_in. This is needed to avoid looping back
256 * to this routine from writefd_unbuffered(). */
259 read_loop(fd, buf, 4);
262 len = tag & 0xFFFFFF;
263 tag = (tag >> 24) - MPLEX_BASE;
267 if (len != 0 || !am_generator) {
268 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
269 exit_cleanup(RERR_STREAMIO);
271 flist_ndx_push(&redo_list, -1);
274 if (len != 4 || !am_generator) {
275 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
276 exit_cleanup(RERR_STREAMIO);
278 read_loop(fd, buf, 4);
279 if (remove_source_files)
280 decrement_active_files(IVAL(buf,0));
281 flist_ndx_push(&redo_list, IVAL(buf,0));
284 if (len >= (int)sizeof buf || !am_generator) {
285 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
286 exit_cleanup(RERR_STREAMIO);
288 read_loop(fd, buf, len);
289 send_msg(MSG_DELETED, buf, len);
292 if (len != 4 || !am_generator) {
293 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
294 exit_cleanup(RERR_STREAMIO);
296 read_loop(fd, buf, len);
297 if (remove_source_files) {
298 decrement_active_files(IVAL(buf,0));
299 send_msg(MSG_SUCCESS, buf, len);
301 if (preserve_hard_links)
302 flist_ndx_push(&hlink_list, IVAL(buf,0));
306 rprintf(FERROR, "invalid message %d:%d\n", tag, len);
307 exit_cleanup(RERR_STREAMIO);
309 close_multiplexing_out();
318 read_loop(fd, buf, n);
319 rwrite((enum logcode)tag, buf, n);
324 rprintf(FERROR, "unknown message %d:%d [%s]\n",
325 tag, len, who_am_i());
326 exit_cleanup(RERR_STREAMIO);
332 /* This is used by the generator to limit how many file transfers can
333 * be active at once when --remove-source-files is specified. Without
334 * this, sender-side deletions were mostly happening at the end. */
335 void increment_active_files(int ndx, int itemizing, enum logcode code)
337 /* TODO: tune these limits? */
338 while (active_filecnt >= (active_bytecnt >= 128*1024 ? 10 : 50)) {
340 check_for_finished_hlinks(itemizing, code);
345 active_bytecnt += the_file_list->files[ndx]->length;
348 void decrement_active_files(int ndx)
351 active_bytecnt -= the_file_list->files[ndx]->length;
354 /* Try to push messages off the list onto the wire. If we leave with more
355 * to do, return 0. On error, return -1. If everything flushed, return 1.
356 * This is only active in the receiver. */
357 static int msg2genr_flush(int flush_it_all)
359 static int written = 0;
366 while (msg2genr.head) {
367 struct msg_list_item *m = msg2genr.head;
368 int n = write(msg_fd_out, m->buf + written, m->len - written);
372 if (errno != EWOULDBLOCK && errno != EAGAIN)
377 FD_SET(msg_fd_out, &fds);
378 tv.tv_sec = select_timeout;
380 if (!select(msg_fd_out+1, NULL, &fds, NULL, &tv))
382 } else if ((written += n) == m->len) {
383 msg2genr.head = m->next;
385 msg2genr.tail = NULL;
393 int send_msg(enum msgcode code, const char *buf, int len)
395 if (msg_fd_out < 0) {
396 if (!defer_forwarding_messages)
397 return io_multiplex_write(code, buf, len);
398 if (!io_multiplexing_out)
400 msg_list_add(&msg2sndr, code, buf, len);
403 msg_list_add(&msg2genr, code, buf, len);
404 msg2genr_flush(NORMAL_FLUSH);
408 void send_msg_int(enum msgcode code, int num)
411 SIVAL(numbuf, 0, num);
412 send_msg(code, numbuf, 4);
415 int get_redo_num(int itemizing, enum logcode code)
419 check_for_finished_hlinks(itemizing, code);
425 return flist_ndx_pop(&redo_list);
428 int get_hlink_num(void)
430 return flist_ndx_pop(&hlink_list);
434 * When we're the receiver and we have a local --files-from list of names
435 * that needs to be sent over the socket to the sender, we have to do two
436 * things at the same time: send the sender a list of what files we're
437 * processing and read the incoming file+info list from the sender. We do
438 * this by augmenting the read_timeout() function to copy this data. It
439 * uses the io_filesfrom_buf to read a block of data from f_in (when it is
440 * ready, since it might be a pipe) and then blast it out f_out (when it
441 * is ready to receive more data).
443 void io_set_filesfrom_fds(int f_in, int f_out)
445 io_filesfrom_f_in = f_in;
446 io_filesfrom_f_out = f_out;
447 io_filesfrom_bp = io_filesfrom_buf;
448 io_filesfrom_lastchar = '\0';
449 io_filesfrom_buflen = 0;
452 /* It's almost always an error to get an EOF when we're trying to read from the
453 * network, because the protocol is (for the most part) self-terminating.
455 * There is one case for the receiver when it is at the end of the transfer
456 * (hanging around reading any keep-alive packets that might come its way): if
457 * the sender dies before the generator's kill-signal comes through, we can end
458 * up here needing to loop until the kill-signal arrives. In this situation,
459 * kluge_around_eof will be < 0.
461 * There is another case for older protocol versions (< 24) where the module
462 * listing was not terminated, so we must ignore an EOF error in that case and
463 * exit. In this situation, kluge_around_eof will be > 0. */
464 static void whine_about_eof(int fd)
466 if (kluge_around_eof && fd == sock_f_in) {
468 if (kluge_around_eof > 0)
470 /* If we're still here after 10 seconds, exit with an error. */
471 for (i = 10*1000/20; i--; )
475 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
476 "(%.0f bytes received so far) [%s]\n",
477 (double)stats.total_read, who_am_i());
479 exit_cleanup(RERR_STREAMIO);
483 * Read from a socket with I/O timeout. return the number of bytes
484 * read. If no bytes can be read then exit, never return a number <= 0.
486 * TODO: If the remote shell connection fails, then current versions
487 * actually report an "unexpected EOF" error here. Since it's a
488 * fairly common mistake to try to use rsh when ssh is required, we
489 * should trap that: if we fail to read any data at all, we should
490 * give a better explanation. We can tell whether the connection has
491 * started by looking e.g. at whether the remote version is known yet.
493 static int read_timeout(int fd, char *buf, size_t len)
497 io_flush(NORMAL_FLUSH);
500 /* until we manage to read *something* */
510 FD_SET(msg_fd_out, &w_fds);
511 if (msg_fd_out > maxfd)
514 if (io_filesfrom_f_out >= 0) {
516 if (io_filesfrom_buflen == 0) {
517 if (io_filesfrom_f_in >= 0) {
518 FD_SET(io_filesfrom_f_in, &r_fds);
519 new_fd = io_filesfrom_f_in;
521 io_filesfrom_f_out = -1;
525 FD_SET(io_filesfrom_f_out, &w_fds);
526 new_fd = io_filesfrom_f_out;
532 tv.tv_sec = select_timeout;
537 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
541 exit_cleanup(RERR_SOCKETIO);
546 if (msg2genr.head && FD_ISSET(msg_fd_out, &w_fds))
547 msg2genr_flush(NORMAL_FLUSH);
549 if (io_filesfrom_f_out >= 0) {
550 if (io_filesfrom_buflen) {
551 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
552 int l = write(io_filesfrom_f_out,
554 io_filesfrom_buflen);
556 if (!(io_filesfrom_buflen -= l))
557 io_filesfrom_bp = io_filesfrom_buf;
559 io_filesfrom_bp += l;
561 /* XXX should we complain? */
562 io_filesfrom_f_out = -1;
565 } else if (io_filesfrom_f_in >= 0) {
566 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
567 int l = read(io_filesfrom_f_in,
569 sizeof io_filesfrom_buf);
571 /* Send end-of-file marker */
572 io_filesfrom_buf[0] = '\0';
573 io_filesfrom_buf[1] = '\0';
574 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
575 io_filesfrom_f_in = -1;
578 char *s = io_filesfrom_buf + l;
579 /* Transform CR and/or LF into '\0' */
580 while (s-- > io_filesfrom_buf) {
581 if (*s == '\n' || *s == '\r')
585 if (!io_filesfrom_lastchar) {
586 /* Last buf ended with a '\0', so don't
587 * let this buf start with one. */
588 while (l && !*io_filesfrom_bp)
589 io_filesfrom_bp++, l--;
592 io_filesfrom_bp = io_filesfrom_buf;
594 char *f = io_filesfrom_bp;
597 /* Eliminate any multi-'\0' runs. */
599 if (!(*t++ = *f++)) {
600 while (f != eob && !*f)
604 io_filesfrom_lastchar = f[-1];
606 io_filesfrom_buflen = l;
612 if (!FD_ISSET(fd, &r_fds))
615 n = read(fd, buf, len);
619 whine_about_eof(fd); /* Doesn't return. */
620 if (errno == EINTR || errno == EWOULDBLOCK
624 /* Don't write errors on a dead socket. */
625 if (fd == sock_f_in) {
626 close_multiplexing_out();
627 rsyserr(FSOCKERR, errno, "read error");
629 rsyserr(FERROR, errno, "read error");
630 exit_cleanup(RERR_STREAMIO);
637 if (fd == sock_f_in && io_timeout)
638 last_io_in = time(NULL);
645 * Read a line into the "fname" buffer (which must be at least MAXPATHLEN
648 int read_filesfrom_line(int fd, char *fname)
650 char ch, *s, *eob = fname + MAXPATHLEN - 1;
652 int reading_remotely = filesfrom_host != NULL;
653 int nulls = eol_nulls || reading_remotely;
658 cnt = read(fd, &ch, 1);
659 if (cnt < 0 && (errno == EWOULDBLOCK
660 || errno == EINTR || errno == EAGAIN)) {
667 tv.tv_sec = select_timeout;
669 if (!select(fd+1, &r_fds, NULL, &e_fds, &tv))
671 if (FD_ISSET(fd, &e_fds)) {
672 rsyserr(FINFO, errno,
673 "select exception on fd %d", fd);
679 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
680 /* Skip empty lines if reading locally. */
681 if (!reading_remotely && s == fname)
691 if (*fname == '#' || *fname == ';')
697 static char *iobuf_out;
698 static int iobuf_out_cnt;
700 void io_start_buffering_out(void)
704 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
705 out_of_memory("io_start_buffering_out");
709 static char *iobuf_in;
710 static size_t iobuf_in_siz;
712 void io_start_buffering_in(void)
716 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
717 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
718 out_of_memory("io_start_buffering_in");
721 void io_end_buffering(void)
723 io_flush(NORMAL_FLUSH);
724 if (!io_multiplexing_out) {
730 void maybe_flush_socket(void)
732 if (iobuf_out && iobuf_out_cnt && time(NULL) - last_io_out >= 5)
733 io_flush(NORMAL_FLUSH);
736 void maybe_send_keepalive(void)
738 if (time(NULL) - last_io_out >= allowed_lull) {
739 if (!iobuf_out || !iobuf_out_cnt) {
740 if (protocol_version < 29)
741 return; /* there's nothing we can do */
742 write_int(sock_f_out, the_file_list->count);
743 write_shortint(sock_f_out, ITEM_IS_NEW);
746 io_flush(NORMAL_FLUSH);
751 * Continue trying to read len bytes - don't return until len has been
754 static void read_loop(int fd, char *buf, size_t len)
757 int n = read_timeout(fd, buf, len);
765 * Read from the file descriptor handling multiplexing - return number
768 * Never returns <= 0.
770 static int readfd_unbuffered(int fd, char *buf, size_t len)
772 static size_t remaining;
773 static size_t iobuf_in_ndx;
776 char line[BIGPATHBUFLEN];
778 if (!iobuf_in || fd != sock_f_in)
779 return read_timeout(fd, buf, len);
781 if (!io_multiplexing_in && remaining == 0) {
782 remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
788 len = MIN(len, remaining);
789 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
796 read_loop(fd, line, 4);
799 msg_bytes = tag & 0xFFFFFF;
800 tag = (tag >> 24) - MPLEX_BASE;
804 if (msg_bytes > iobuf_in_siz) {
805 if (!(iobuf_in = realloc_array(iobuf_in, char,
807 out_of_memory("readfd_unbuffered");
808 iobuf_in_siz = msg_bytes;
810 read_loop(fd, iobuf_in, msg_bytes);
811 remaining = msg_bytes;
815 if (msg_bytes >= sizeof line)
817 read_loop(fd, line, msg_bytes);
818 /* A directory name was sent with the trailing null */
819 if (msg_bytes > 0 && !line[msg_bytes-1])
820 log_delete(line, S_IFDIR);
822 line[msg_bytes] = '\0';
823 log_delete(line, S_IFREG);
827 if (msg_bytes != 4) {
828 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
829 tag, (long)msg_bytes, who_am_i());
830 exit_cleanup(RERR_STREAMIO);
832 read_loop(fd, line, msg_bytes);
833 successful_send(IVAL(line, 0));
837 if (msg_bytes >= sizeof line) {
840 "multiplexing overflow %d:%ld [%s]\n",
841 tag, (long)msg_bytes, who_am_i());
842 exit_cleanup(RERR_STREAMIO);
844 read_loop(fd, line, msg_bytes);
845 rwrite((enum logcode)tag, line, msg_bytes);
848 rprintf(FERROR, "unexpected tag %d [%s]\n",
850 exit_cleanup(RERR_STREAMIO);
855 io_flush(NORMAL_FLUSH);
861 * Do a buffered read from @p fd. Don't return until all @p n bytes
862 * have been read. If all @p n can't be read then exit with an
865 static void readfd(int fd, char *buffer, size_t N)
871 cnt = readfd_unbuffered(fd, buffer + total, N-total);
875 if (fd == write_batch_monitor_in) {
876 if ((size_t)write(batch_fd, buffer, total) != total)
877 exit_cleanup(RERR_FILEIO);
881 stats.total_read += total;
884 unsigned short read_shortint(int f)
888 return (UVAL(b, 1) << 8) + UVAL(b, 0);
891 int32 read_int(int f)
899 if (num & (int32)0x80000000)
900 num |= ~(int32)0xffffffff;
905 int64 read_longint(int f)
910 if (protocol_version < 30) {
913 if ((int32)num != (int32)0xffffffff)
917 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
918 exit_cleanup(RERR_UNSUPPORTED);
921 num = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
926 cnt = int_byte_cnt[CVAL(b, 0)];
928 if (cnt > 5 || (cnt == 5 && (CVAL(b,0)&0x3F || CVAL(b,1)&0x80))) {
929 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
930 exit_cleanup(RERR_UNSUPPORTED);
934 readfd(f, b + 3, cnt - 3);
940 num = NVAL4(b, 0x80);
943 num = NVAL5(b, 0xC0);
945 #if SIZEOF_INT64 >= 8
947 num = NVAL6(b, 0xE0);
950 num = NVAL7(b, 0xF0);
953 num = NVAL8(b, 0xF8);
960 exit_cleanup(RERR_PROTOCOL); /* impossible... */
967 void read_buf(int f, char *buf, size_t len)
972 void read_sbuf(int f, char *buf, size_t len)
978 uchar read_byte(int f)
981 readfd(f, (char *)&c, 1);
985 int read_vstring(int f, char *buf, int bufsize)
987 int len = read_byte(f);
990 len = (len & ~0x80) * 0x100 + read_byte(f);
992 if (len >= bufsize) {
993 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
1004 /* Populate a sum_struct with values from the socket. This is
1005 * called by both the sender and the receiver. */
1006 void read_sum_head(int f, struct sum_struct *sum)
1008 sum->count = read_int(f);
1009 if (sum->count < 0) {
1010 rprintf(FERROR, "Invalid checksum count %ld [%s]\n",
1011 (long)sum->count, who_am_i());
1012 exit_cleanup(RERR_PROTOCOL);
1014 sum->blength = read_int(f);
1015 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
1016 rprintf(FERROR, "Invalid block length %ld [%s]\n",
1017 (long)sum->blength, who_am_i());
1018 exit_cleanup(RERR_PROTOCOL);
1020 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
1021 if (sum->s2length < 0 || sum->s2length > MD4_SUM_LENGTH) {
1022 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
1023 sum->s2length, who_am_i());
1024 exit_cleanup(RERR_PROTOCOL);
1026 sum->remainder = read_int(f);
1027 if (sum->remainder < 0 || sum->remainder > sum->blength) {
1028 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
1029 (long)sum->remainder, who_am_i());
1030 exit_cleanup(RERR_PROTOCOL);
1034 /* Send the values from a sum_struct over the socket. Set sum to
1035 * NULL if there are no checksums to send. This is called by both
1036 * the generator and the sender. */
1037 void write_sum_head(int f, struct sum_struct *sum)
1039 static struct sum_struct null_sum;
1044 write_int(f, sum->count);
1045 write_int(f, sum->blength);
1046 if (protocol_version >= 27)
1047 write_int(f, sum->s2length);
1048 write_int(f, sum->remainder);
1052 * Sleep after writing to limit I/O bandwidth usage.
1054 * @todo Rather than sleeping after each write, it might be better to
1055 * use some kind of averaging. The current algorithm seems to always
1056 * use a bit less bandwidth than specified, because it doesn't make up
1057 * for slow periods. But arguably this is a feature. In addition, we
1058 * ought to take the time used to write the data into account.
1060 * During some phases of big transfers (file FOO is uptodate) this is
1061 * called with a small bytes_written every time. As the kernel has to
1062 * round small waits up to guarantee that we actually wait at least the
1063 * requested number of microseconds, this can become grossly inaccurate.
1064 * We therefore keep track of the bytes we've written over time and only
1065 * sleep when the accumulated delay is at least 1 tenth of a second.
1067 static void sleep_for_bwlimit(int bytes_written)
1069 static struct timeval prior_tv;
1070 static long total_written = 0;
1071 struct timeval tv, start_tv;
1072 long elapsed_usec, sleep_usec;
1074 #define ONE_SEC 1000000L /* # of microseconds in a second */
1076 if (!bwlimit_writemax)
1079 total_written += bytes_written;
1081 gettimeofday(&start_tv, NULL);
1082 if (prior_tv.tv_sec) {
1083 elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
1084 + (start_tv.tv_usec - prior_tv.tv_usec);
1085 total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
1086 if (total_written < 0)
1090 sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
1091 if (sleep_usec < ONE_SEC / 10) {
1092 prior_tv = start_tv;
1096 tv.tv_sec = sleep_usec / ONE_SEC;
1097 tv.tv_usec = sleep_usec % ONE_SEC;
1098 select(0, NULL, NULL, NULL, &tv);
1100 gettimeofday(&prior_tv, NULL);
1101 elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
1102 + (prior_tv.tv_usec - start_tv.tv_usec);
1103 total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
1106 /* Write len bytes to the file descriptor fd, looping as necessary to get
1107 * the job done and also (in certain circumstances) reading any data on
1108 * msg_fd_in to avoid deadlock.
1110 * This function underlies the multiplexing system. The body of the
1111 * application never calls this function directly. */
1112 static void writefd_unbuffered(int fd, const char *buf, size_t len)
1114 size_t n, total = 0;
1115 fd_set w_fds, r_fds, e_fds;
1116 int maxfd, count, cnt, using_r_fds;
1117 int defer_save = defer_forwarding_messages;
1122 while (total < len) {
1129 if (msg_fd_in >= 0) {
1131 FD_SET(msg_fd_in, &r_fds);
1132 if (msg_fd_in > maxfd)
1138 tv.tv_sec = select_timeout;
1142 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1143 &w_fds, &e_fds, &tv);
1146 if (count < 0 && errno == EBADF)
1147 exit_cleanup(RERR_SOCKETIO);
1152 if (FD_ISSET(fd, &e_fds)) {
1153 rsyserr(FINFO, errno,
1154 "select exception on fd %d", fd);
1157 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1160 if (!FD_ISSET(fd, &w_fds))
1164 if (bwlimit_writemax && n > bwlimit_writemax)
1165 n = bwlimit_writemax;
1166 cnt = write(fd, buf + total, n);
1172 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1178 /* Don't try to write errors back across the stream. */
1179 if (fd == sock_f_out)
1180 close_multiplexing_out();
1181 rsyserr(FERROR, errno,
1182 "writefd_unbuffered failed to write %ld bytes [%s]",
1183 (long)len, who_am_i());
1184 /* If the other side is sending us error messages, try
1185 * to grab any messages they sent before they died. */
1186 while (fd == sock_f_out && io_multiplexing_in) {
1189 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1190 sizeof io_filesfrom_buf);
1192 exit_cleanup(RERR_STREAMIO);
1196 defer_forwarding_messages = 1;
1198 if (fd == sock_f_out) {
1199 if (io_timeout || am_generator)
1200 last_io_out = time(NULL);
1201 sleep_for_bwlimit(cnt);
1205 defer_forwarding_messages = defer_save;
1209 static void msg2sndr_flush(void)
1211 if (defer_forwarding_messages)
1214 while (msg2sndr.head && io_multiplexing_out) {
1215 struct msg_list_item *m = msg2sndr.head;
1216 if (!(msg2sndr.head = m->next))
1217 msg2sndr.tail = NULL;
1218 stats.total_written += m->len;
1219 defer_forwarding_messages = 1;
1220 writefd_unbuffered(sock_f_out, m->buf, m->len);
1221 defer_forwarding_messages = 0;
1227 * Write an message to a multiplexed stream. If this fails then rsync
1230 static void mplex_write(enum msgcode code, const char *buf, size_t len)
1235 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
1237 if (n > sizeof buffer - 4)
1240 memcpy(buffer + 4, buf, n);
1242 writefd_unbuffered(sock_f_out, buffer, n+4);
1248 defer_forwarding_messages = 1;
1249 writefd_unbuffered(sock_f_out, buf, len);
1250 defer_forwarding_messages = 0;
1255 void io_flush(int flush_it_all)
1257 msg2genr_flush(flush_it_all);
1260 if (!iobuf_out_cnt || no_flush)
1263 if (io_multiplexing_out)
1264 mplex_write(MSG_DATA, iobuf_out, iobuf_out_cnt);
1266 writefd_unbuffered(sock_f_out, iobuf_out, iobuf_out_cnt);
1270 static void writefd(int fd, const char *buf, size_t len)
1272 if (fd == msg_fd_out) {
1273 rprintf(FERROR, "Internal error: wrong write used in receiver.\n");
1274 exit_cleanup(RERR_PROTOCOL);
1277 if (fd == sock_f_out)
1278 stats.total_written += len;
1280 if (fd == write_batch_monitor_out) {
1281 if ((size_t)write(batch_fd, buf, len) != len)
1282 exit_cleanup(RERR_FILEIO);
1285 if (!iobuf_out || fd != sock_f_out) {
1286 writefd_unbuffered(fd, buf, len);
1291 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1293 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1299 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1300 io_flush(NORMAL_FLUSH);
1304 void write_shortint(int f, unsigned short x)
1308 b[1] = (char)(x >> 8);
1312 void write_int(int f, int32 x)
1320 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1321 * 64-bit types on this platform.
1323 void write_longint(int f, int64 x)
1327 #if SIZEOF_INT64 < 8
1328 if (x < 0 || x > 0x7FFFFFFF) {
1329 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1330 exit_cleanup(RERR_UNSUPPORTED);
1334 if (protocol_version < 30) {
1335 char * const s = b+4;
1337 #if SIZEOF_INT64 < 8
1340 if (x <= 0x7FFFFFFF && x >= 0) {
1346 SIVAL(s, 4, x >> 32);
1351 } else if (x < ((int32)1<<(3*8-1))) {
1352 b[0] = (char)(x >> 16);
1353 b[1] = (char)(x >> 8);
1356 } else if (x < ((int64)1<<(4*8-2))) {
1357 b[0] = (char)((x >> 24) | 0x80);
1358 b[1] = (char)(x >> 16);
1359 b[2] = (char)(x >> 8);
1362 #if SIZEOF_INT64 < 8
1365 b[1] = (char)(x >> 24);
1366 b[2] = (char)(x >> 16);
1367 b[3] = (char)(x >> 8);
1372 } else if (x < ((int64)1<<(5*8-3))) {
1373 b[0] = (char)((x >> 32) | 0xC0);
1374 b[1] = (char)(x >> 24);
1375 b[2] = (char)(x >> 16);
1376 b[3] = (char)(x >> 8);
1379 } else if (x < ((int64)1<<(6*8-4))) {
1380 b[0] = (char)((x >> 40) | 0xE0);
1381 b[1] = (char)(x >> 32);
1382 b[2] = (char)(x >> 24);
1383 b[3] = (char)(x >> 16);
1384 b[4] = (char)(x >> 8);
1387 } else if (x < ((int64)1<<(7*8-5))) {
1388 b[0] = (char)((x >> 48) | 0xF0);
1389 b[1] = (char)(x >> 40);
1390 b[2] = (char)(x >> 32);
1391 b[3] = (char)(x >> 24);
1392 b[4] = (char)(x >> 16);
1393 b[5] = (char)(x >> 8);
1396 } else if (x < ((int64)1<<(8*8-6))) {
1397 b[0] = (char)((x >> 56) | 0xF8);
1398 b[1] = (char)(x >> 48);
1399 b[2] = (char)(x >> 40);
1400 b[3] = (char)(x >> 32);
1401 b[4] = (char)(x >> 24);
1402 b[5] = (char)(x >> 16);
1403 b[6] = (char)(x >> 8);
1409 b[1] = (char)(x >> 56);
1410 b[2] = (char)(x >> 48);
1411 b[3] = (char)(x >> 40);
1412 b[4] = (char)(x >> 32);
1413 b[5] = (char)(x >> 24);
1414 b[6] = (char)(x >> 16);
1415 b[7] = (char)(x >> 8);
1422 void write_buf(int f, const char *buf, size_t len)
1427 /** Write a string to the connection */
1428 void write_sbuf(int f, const char *buf)
1430 writefd(f, buf, strlen(buf));
1433 void write_byte(int f, uchar c)
1435 writefd(f, (char *)&c, 1);
1438 void write_vstring(int f, const char *str, int len)
1440 uchar lenbuf[3], *lb = lenbuf;
1445 "attempting to send over-long vstring (%d > %d)\n",
1447 exit_cleanup(RERR_PROTOCOL);
1449 *lb++ = len / 0x100 + 0x80;
1453 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1455 writefd(f, str, len);
1459 * Read a line of up to @p maxlen characters into @p buf (not counting
1460 * the trailing null). Strips the (required) trailing newline and all
1463 * @return 1 for success; 0 for I/O error or truncation.
1465 int read_line(int f, char *buf, size_t maxlen)
1469 read_buf(f, buf, 1);
1474 if (buf[0] != '\r') {
1483 void io_printf(int fd, const char *format, ...)
1486 char buf[BIGPATHBUFLEN];
1489 va_start(ap, format);
1490 len = vsnprintf(buf, sizeof buf, format, ap);
1494 exit_cleanup(RERR_STREAMIO);
1496 if (len > (int)sizeof buf) {
1497 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1498 exit_cleanup(RERR_STREAMIO);
1501 write_sbuf(fd, buf);
1504 /** Setup for multiplexing a MSG_* stream with the data stream. */
1505 void io_start_multiplex_out(void)
1507 io_flush(NORMAL_FLUSH);
1508 io_start_buffering_out();
1509 io_multiplexing_out = 1;
1512 /** Setup for multiplexing a MSG_* stream with the data stream. */
1513 void io_start_multiplex_in(void)
1515 io_flush(NORMAL_FLUSH);
1516 io_start_buffering_in();
1517 io_multiplexing_in = 1;
1520 /** Write an message to the multiplexed data stream. */
1521 int io_multiplex_write(enum msgcode code, const char *buf, size_t len)
1523 if (!io_multiplexing_out)
1526 io_flush(NORMAL_FLUSH);
1527 stats.total_written += (len+4);
1528 mplex_write(code, buf, len);
1532 void close_multiplexing_in(void)
1534 io_multiplexing_in = 0;
1537 /** Stop output multiplexing. */
1538 void close_multiplexing_out(void)
1540 io_multiplexing_out = 0;
1543 void start_write_batch(int fd)
1545 write_stream_flags(batch_fd);
1547 /* Some communication has already taken place, but we don't
1548 * enable batch writing until here so that we can write a
1549 * canonical record of the communication even though the
1550 * actual communication so far depends on whether a daemon
1552 write_int(batch_fd, protocol_version);
1553 write_int(batch_fd, checksum_seed);
1556 write_batch_monitor_out = fd;
1558 write_batch_monitor_in = fd;
1561 void stop_write_batch(void)
1563 write_batch_monitor_out = -1;
1564 write_batch_monitor_in = -1;