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)) {
339 #ifdef SUPPORT_HARD_LINKS
341 check_for_finished_hlinks(itemizing, code);
347 active_bytecnt += F_LENGTH(the_file_list->files[ndx]);
350 void decrement_active_files(int ndx)
353 active_bytecnt -= F_LENGTH(the_file_list->files[ndx]);
356 /* Try to push messages off the list onto the wire. If we leave with more
357 * to do, return 0. On error, return -1. If everything flushed, return 1.
358 * This is only active in the receiver. */
359 static int msg2genr_flush(int flush_it_all)
361 static int written = 0;
368 while (msg2genr.head) {
369 struct msg_list_item *m = msg2genr.head;
370 int n = write(msg_fd_out, m->buf + written, m->len - written);
374 if (errno != EWOULDBLOCK && errno != EAGAIN)
379 FD_SET(msg_fd_out, &fds);
380 tv.tv_sec = select_timeout;
382 if (!select(msg_fd_out+1, NULL, &fds, NULL, &tv))
384 } else if ((written += n) == m->len) {
385 msg2genr.head = m->next;
387 msg2genr.tail = NULL;
395 int send_msg(enum msgcode code, const char *buf, int len)
397 if (msg_fd_out < 0) {
398 if (!defer_forwarding_messages)
399 return io_multiplex_write(code, buf, len);
400 if (!io_multiplexing_out)
402 msg_list_add(&msg2sndr, code, buf, len);
405 msg_list_add(&msg2genr, code, buf, len);
406 msg2genr_flush(NORMAL_FLUSH);
410 void send_msg_int(enum msgcode code, int num)
413 SIVAL(numbuf, 0, num);
414 send_msg(code, numbuf, 4);
417 int get_redo_num(int itemizing, enum logcode code)
420 #ifdef SUPPORT_HARD_LINKS
422 check_for_finished_hlinks(itemizing, code);
429 return flist_ndx_pop(&redo_list);
432 int get_hlink_num(void)
434 return flist_ndx_pop(&hlink_list);
438 * When we're the receiver and we have a local --files-from list of names
439 * that needs to be sent over the socket to the sender, we have to do two
440 * things at the same time: send the sender a list of what files we're
441 * processing and read the incoming file+info list from the sender. We do
442 * this by augmenting the read_timeout() function to copy this data. It
443 * uses the io_filesfrom_buf to read a block of data from f_in (when it is
444 * ready, since it might be a pipe) and then blast it out f_out (when it
445 * is ready to receive more data).
447 void io_set_filesfrom_fds(int f_in, int f_out)
449 io_filesfrom_f_in = f_in;
450 io_filesfrom_f_out = f_out;
451 io_filesfrom_bp = io_filesfrom_buf;
452 io_filesfrom_lastchar = '\0';
453 io_filesfrom_buflen = 0;
456 /* It's almost always an error to get an EOF when we're trying to read from the
457 * network, because the protocol is (for the most part) self-terminating.
459 * There is one case for the receiver when it is at the end of the transfer
460 * (hanging around reading any keep-alive packets that might come its way): if
461 * the sender dies before the generator's kill-signal comes through, we can end
462 * up here needing to loop until the kill-signal arrives. In this situation,
463 * kluge_around_eof will be < 0.
465 * There is another case for older protocol versions (< 24) where the module
466 * listing was not terminated, so we must ignore an EOF error in that case and
467 * exit. In this situation, kluge_around_eof will be > 0. */
468 static void whine_about_eof(int fd)
470 if (kluge_around_eof && fd == sock_f_in) {
472 if (kluge_around_eof > 0)
474 /* If we're still here after 10 seconds, exit with an error. */
475 for (i = 10*1000/20; i--; )
479 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
480 "(%.0f bytes received so far) [%s]\n",
481 (double)stats.total_read, who_am_i());
483 exit_cleanup(RERR_STREAMIO);
487 * Read from a socket with I/O timeout. return the number of bytes
488 * read. If no bytes can be read then exit, never return a number <= 0.
490 * TODO: If the remote shell connection fails, then current versions
491 * actually report an "unexpected EOF" error here. Since it's a
492 * fairly common mistake to try to use rsh when ssh is required, we
493 * should trap that: if we fail to read any data at all, we should
494 * give a better explanation. We can tell whether the connection has
495 * started by looking e.g. at whether the remote version is known yet.
497 static int read_timeout(int fd, char *buf, size_t len)
501 io_flush(NORMAL_FLUSH);
504 /* until we manage to read *something* */
514 FD_SET(msg_fd_out, &w_fds);
515 if (msg_fd_out > maxfd)
518 if (io_filesfrom_f_out >= 0) {
520 if (io_filesfrom_buflen == 0) {
521 if (io_filesfrom_f_in >= 0) {
522 FD_SET(io_filesfrom_f_in, &r_fds);
523 new_fd = io_filesfrom_f_in;
525 io_filesfrom_f_out = -1;
529 FD_SET(io_filesfrom_f_out, &w_fds);
530 new_fd = io_filesfrom_f_out;
536 tv.tv_sec = select_timeout;
541 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
545 exit_cleanup(RERR_SOCKETIO);
550 if (msg2genr.head && FD_ISSET(msg_fd_out, &w_fds))
551 msg2genr_flush(NORMAL_FLUSH);
553 if (io_filesfrom_f_out >= 0) {
554 if (io_filesfrom_buflen) {
555 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
556 int l = write(io_filesfrom_f_out,
558 io_filesfrom_buflen);
560 if (!(io_filesfrom_buflen -= l))
561 io_filesfrom_bp = io_filesfrom_buf;
563 io_filesfrom_bp += l;
565 /* XXX should we complain? */
566 io_filesfrom_f_out = -1;
569 } else if (io_filesfrom_f_in >= 0) {
570 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
571 int l = read(io_filesfrom_f_in,
573 sizeof io_filesfrom_buf);
575 /* Send end-of-file marker */
576 io_filesfrom_buf[0] = '\0';
577 io_filesfrom_buf[1] = '\0';
578 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
579 io_filesfrom_f_in = -1;
582 char *s = io_filesfrom_buf + l;
583 /* Transform CR and/or LF into '\0' */
584 while (s-- > io_filesfrom_buf) {
585 if (*s == '\n' || *s == '\r')
589 if (!io_filesfrom_lastchar) {
590 /* Last buf ended with a '\0', so don't
591 * let this buf start with one. */
592 while (l && !*io_filesfrom_bp)
593 io_filesfrom_bp++, l--;
596 io_filesfrom_bp = io_filesfrom_buf;
598 char *f = io_filesfrom_bp;
601 /* Eliminate any multi-'\0' runs. */
603 if (!(*t++ = *f++)) {
604 while (f != eob && !*f)
608 io_filesfrom_lastchar = f[-1];
610 io_filesfrom_buflen = l;
616 if (!FD_ISSET(fd, &r_fds))
619 n = read(fd, buf, len);
623 whine_about_eof(fd); /* Doesn't return. */
624 if (errno == EINTR || errno == EWOULDBLOCK
628 /* Don't write errors on a dead socket. */
629 if (fd == sock_f_in) {
630 close_multiplexing_out();
631 rsyserr(FSOCKERR, errno, "read error");
633 rsyserr(FERROR, errno, "read error");
634 exit_cleanup(RERR_STREAMIO);
641 if (fd == sock_f_in && io_timeout)
642 last_io_in = time(NULL);
649 * Read a line into the "fname" buffer (which must be at least MAXPATHLEN
652 int read_filesfrom_line(int fd, char *fname)
654 char ch, *s, *eob = fname + MAXPATHLEN - 1;
656 int reading_remotely = filesfrom_host != NULL;
657 int nulls = eol_nulls || reading_remotely;
662 cnt = read(fd, &ch, 1);
663 if (cnt < 0 && (errno == EWOULDBLOCK
664 || errno == EINTR || errno == EAGAIN)) {
671 tv.tv_sec = select_timeout;
673 if (!select(fd+1, &r_fds, NULL, &e_fds, &tv))
675 if (FD_ISSET(fd, &e_fds)) {
676 rsyserr(FINFO, errno,
677 "select exception on fd %d", fd);
683 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
684 /* Skip empty lines if reading locally. */
685 if (!reading_remotely && s == fname)
695 if (*fname == '#' || *fname == ';')
701 static char *iobuf_out;
702 static int iobuf_out_cnt;
704 void io_start_buffering_out(void)
708 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
709 out_of_memory("io_start_buffering_out");
713 static char *iobuf_in;
714 static size_t iobuf_in_siz;
716 void io_start_buffering_in(void)
720 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
721 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
722 out_of_memory("io_start_buffering_in");
725 void io_end_buffering(void)
727 io_flush(NORMAL_FLUSH);
728 if (!io_multiplexing_out) {
734 void maybe_flush_socket(void)
736 if (iobuf_out && iobuf_out_cnt && time(NULL) - last_io_out >= 5)
737 io_flush(NORMAL_FLUSH);
740 void maybe_send_keepalive(void)
742 if (time(NULL) - last_io_out >= allowed_lull) {
743 if (!iobuf_out || !iobuf_out_cnt) {
744 if (protocol_version < 29)
745 return; /* there's nothing we can do */
746 write_int(sock_f_out, the_file_list->count);
747 write_shortint(sock_f_out, ITEM_IS_NEW);
750 io_flush(NORMAL_FLUSH);
755 * Continue trying to read len bytes - don't return until len has been
758 static void read_loop(int fd, char *buf, size_t len)
761 int n = read_timeout(fd, buf, len);
769 * Read from the file descriptor handling multiplexing - return number
772 * Never returns <= 0.
774 static int readfd_unbuffered(int fd, char *buf, size_t len)
776 static size_t remaining;
777 static size_t iobuf_in_ndx;
780 char line[BIGPATHBUFLEN];
782 if (!iobuf_in || fd != sock_f_in)
783 return read_timeout(fd, buf, len);
785 if (!io_multiplexing_in && remaining == 0) {
786 remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
792 len = MIN(len, remaining);
793 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
800 read_loop(fd, line, 4);
803 msg_bytes = tag & 0xFFFFFF;
804 tag = (tag >> 24) - MPLEX_BASE;
808 if (msg_bytes > iobuf_in_siz) {
809 if (!(iobuf_in = realloc_array(iobuf_in, char,
811 out_of_memory("readfd_unbuffered");
812 iobuf_in_siz = msg_bytes;
814 read_loop(fd, iobuf_in, msg_bytes);
815 remaining = msg_bytes;
819 if (msg_bytes >= sizeof line)
821 read_loop(fd, line, msg_bytes);
822 /* A directory name was sent with the trailing null */
823 if (msg_bytes > 0 && !line[msg_bytes-1])
824 log_delete(line, S_IFDIR);
826 line[msg_bytes] = '\0';
827 log_delete(line, S_IFREG);
831 if (msg_bytes != 4) {
832 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
833 tag, (long)msg_bytes, who_am_i());
834 exit_cleanup(RERR_STREAMIO);
836 read_loop(fd, line, msg_bytes);
837 successful_send(IVAL(line, 0));
841 if (msg_bytes >= sizeof line) {
844 "multiplexing overflow %d:%ld [%s]\n",
845 tag, (long)msg_bytes, who_am_i());
846 exit_cleanup(RERR_STREAMIO);
848 read_loop(fd, line, msg_bytes);
849 rwrite((enum logcode)tag, line, msg_bytes);
852 rprintf(FERROR, "unexpected tag %d [%s]\n",
854 exit_cleanup(RERR_STREAMIO);
859 io_flush(NORMAL_FLUSH);
865 * Do a buffered read from @p fd. Don't return until all @p n bytes
866 * have been read. If all @p n can't be read then exit with an
869 static void readfd(int fd, char *buffer, size_t N)
875 cnt = readfd_unbuffered(fd, buffer + total, N-total);
879 if (fd == write_batch_monitor_in) {
880 if ((size_t)write(batch_fd, buffer, total) != total)
881 exit_cleanup(RERR_FILEIO);
885 stats.total_read += total;
888 unsigned short read_shortint(int f)
892 return (UVAL(b, 1) << 8) + UVAL(b, 0);
895 int32 read_int(int f)
903 if (num & (int32)0x80000000)
904 num |= ~(int32)0xffffffff;
909 int64 read_longint(int f)
914 if (protocol_version < 30) {
917 if ((int32)num != (int32)0xffffffff)
921 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
922 exit_cleanup(RERR_UNSUPPORTED);
925 num = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
930 cnt = int_byte_cnt[CVAL(b, 0)];
932 if (cnt > 5 || (cnt == 5 && (CVAL(b,0)&0x3F || CVAL(b,1)&0x80))) {
933 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
934 exit_cleanup(RERR_UNSUPPORTED);
938 readfd(f, b + 3, cnt - 3);
944 num = NVAL4(b, 0x80);
947 num = NVAL5(b, 0xC0);
949 #if SIZEOF_INT64 >= 8
951 num = NVAL6(b, 0xE0);
954 num = NVAL7(b, 0xF0);
957 num = NVAL8(b, 0xF8);
964 exit_cleanup(RERR_PROTOCOL); /* impossible... */
971 void read_buf(int f, char *buf, size_t len)
976 void read_sbuf(int f, char *buf, size_t len)
982 uchar read_byte(int f)
985 readfd(f, (char *)&c, 1);
989 int read_vstring(int f, char *buf, int bufsize)
991 int len = read_byte(f);
994 len = (len & ~0x80) * 0x100 + read_byte(f);
996 if (len >= bufsize) {
997 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
1003 readfd(f, buf, len);
1008 /* Populate a sum_struct with values from the socket. This is
1009 * called by both the sender and the receiver. */
1010 void read_sum_head(int f, struct sum_struct *sum)
1012 sum->count = read_int(f);
1013 if (sum->count < 0) {
1014 rprintf(FERROR, "Invalid checksum count %ld [%s]\n",
1015 (long)sum->count, who_am_i());
1016 exit_cleanup(RERR_PROTOCOL);
1018 sum->blength = read_int(f);
1019 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
1020 rprintf(FERROR, "Invalid block length %ld [%s]\n",
1021 (long)sum->blength, who_am_i());
1022 exit_cleanup(RERR_PROTOCOL);
1024 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
1025 if (sum->s2length < 0 || sum->s2length > MD4_SUM_LENGTH) {
1026 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
1027 sum->s2length, who_am_i());
1028 exit_cleanup(RERR_PROTOCOL);
1030 sum->remainder = read_int(f);
1031 if (sum->remainder < 0 || sum->remainder > sum->blength) {
1032 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
1033 (long)sum->remainder, who_am_i());
1034 exit_cleanup(RERR_PROTOCOL);
1038 /* Send the values from a sum_struct over the socket. Set sum to
1039 * NULL if there are no checksums to send. This is called by both
1040 * the generator and the sender. */
1041 void write_sum_head(int f, struct sum_struct *sum)
1043 static struct sum_struct null_sum;
1048 write_int(f, sum->count);
1049 write_int(f, sum->blength);
1050 if (protocol_version >= 27)
1051 write_int(f, sum->s2length);
1052 write_int(f, sum->remainder);
1056 * Sleep after writing to limit I/O bandwidth usage.
1058 * @todo Rather than sleeping after each write, it might be better to
1059 * use some kind of averaging. The current algorithm seems to always
1060 * use a bit less bandwidth than specified, because it doesn't make up
1061 * for slow periods. But arguably this is a feature. In addition, we
1062 * ought to take the time used to write the data into account.
1064 * During some phases of big transfers (file FOO is uptodate) this is
1065 * called with a small bytes_written every time. As the kernel has to
1066 * round small waits up to guarantee that we actually wait at least the
1067 * requested number of microseconds, this can become grossly inaccurate.
1068 * We therefore keep track of the bytes we've written over time and only
1069 * sleep when the accumulated delay is at least 1 tenth of a second.
1071 static void sleep_for_bwlimit(int bytes_written)
1073 static struct timeval prior_tv;
1074 static long total_written = 0;
1075 struct timeval tv, start_tv;
1076 long elapsed_usec, sleep_usec;
1078 #define ONE_SEC 1000000L /* # of microseconds in a second */
1080 if (!bwlimit_writemax)
1083 total_written += bytes_written;
1085 gettimeofday(&start_tv, NULL);
1086 if (prior_tv.tv_sec) {
1087 elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
1088 + (start_tv.tv_usec - prior_tv.tv_usec);
1089 total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
1090 if (total_written < 0)
1094 sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
1095 if (sleep_usec < ONE_SEC / 10) {
1096 prior_tv = start_tv;
1100 tv.tv_sec = sleep_usec / ONE_SEC;
1101 tv.tv_usec = sleep_usec % ONE_SEC;
1102 select(0, NULL, NULL, NULL, &tv);
1104 gettimeofday(&prior_tv, NULL);
1105 elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
1106 + (prior_tv.tv_usec - start_tv.tv_usec);
1107 total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
1110 /* Write len bytes to the file descriptor fd, looping as necessary to get
1111 * the job done and also (in certain circumstances) reading any data on
1112 * msg_fd_in to avoid deadlock.
1114 * This function underlies the multiplexing system. The body of the
1115 * application never calls this function directly. */
1116 static void writefd_unbuffered(int fd, const char *buf, size_t len)
1118 size_t n, total = 0;
1119 fd_set w_fds, r_fds, e_fds;
1120 int maxfd, count, cnt, using_r_fds;
1121 int defer_save = defer_forwarding_messages;
1126 while (total < len) {
1133 if (msg_fd_in >= 0) {
1135 FD_SET(msg_fd_in, &r_fds);
1136 if (msg_fd_in > maxfd)
1142 tv.tv_sec = select_timeout;
1146 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1147 &w_fds, &e_fds, &tv);
1150 if (count < 0 && errno == EBADF)
1151 exit_cleanup(RERR_SOCKETIO);
1156 if (FD_ISSET(fd, &e_fds)) {
1157 rsyserr(FINFO, errno,
1158 "select exception on fd %d", fd);
1161 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1164 if (!FD_ISSET(fd, &w_fds))
1168 if (bwlimit_writemax && n > bwlimit_writemax)
1169 n = bwlimit_writemax;
1170 cnt = write(fd, buf + total, n);
1176 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1182 /* Don't try to write errors back across the stream. */
1183 if (fd == sock_f_out)
1184 close_multiplexing_out();
1185 rsyserr(FERROR, errno,
1186 "writefd_unbuffered failed to write %ld bytes [%s]",
1187 (long)len, who_am_i());
1188 /* If the other side is sending us error messages, try
1189 * to grab any messages they sent before they died. */
1190 while (fd == sock_f_out && io_multiplexing_in) {
1193 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1194 sizeof io_filesfrom_buf);
1196 exit_cleanup(RERR_STREAMIO);
1200 defer_forwarding_messages = 1;
1202 if (fd == sock_f_out) {
1203 if (io_timeout || am_generator)
1204 last_io_out = time(NULL);
1205 sleep_for_bwlimit(cnt);
1209 defer_forwarding_messages = defer_save;
1213 static void msg2sndr_flush(void)
1215 if (defer_forwarding_messages)
1218 while (msg2sndr.head && io_multiplexing_out) {
1219 struct msg_list_item *m = msg2sndr.head;
1220 if (!(msg2sndr.head = m->next))
1221 msg2sndr.tail = NULL;
1222 stats.total_written += m->len;
1223 defer_forwarding_messages = 1;
1224 writefd_unbuffered(sock_f_out, m->buf, m->len);
1225 defer_forwarding_messages = 0;
1231 * Write an message to a multiplexed stream. If this fails then rsync
1234 static void mplex_write(enum msgcode code, const char *buf, size_t len)
1239 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
1241 if (n > sizeof buffer - 4)
1244 memcpy(buffer + 4, buf, n);
1246 writefd_unbuffered(sock_f_out, buffer, n+4);
1252 defer_forwarding_messages = 1;
1253 writefd_unbuffered(sock_f_out, buf, len);
1254 defer_forwarding_messages = 0;
1259 void io_flush(int flush_it_all)
1261 msg2genr_flush(flush_it_all);
1264 if (!iobuf_out_cnt || no_flush)
1267 if (io_multiplexing_out)
1268 mplex_write(MSG_DATA, iobuf_out, iobuf_out_cnt);
1270 writefd_unbuffered(sock_f_out, iobuf_out, iobuf_out_cnt);
1274 static void writefd(int fd, const char *buf, size_t len)
1276 if (fd == msg_fd_out) {
1277 rprintf(FERROR, "Internal error: wrong write used in receiver.\n");
1278 exit_cleanup(RERR_PROTOCOL);
1281 if (fd == sock_f_out)
1282 stats.total_written += len;
1284 if (fd == write_batch_monitor_out) {
1285 if ((size_t)write(batch_fd, buf, len) != len)
1286 exit_cleanup(RERR_FILEIO);
1289 if (!iobuf_out || fd != sock_f_out) {
1290 writefd_unbuffered(fd, buf, len);
1295 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1297 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1303 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1304 io_flush(NORMAL_FLUSH);
1308 void write_shortint(int f, unsigned short x)
1312 b[1] = (char)(x >> 8);
1316 void write_int(int f, int32 x)
1324 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1325 * 64-bit types on this platform.
1327 void write_longint(int f, int64 x)
1331 #if SIZEOF_INT64 < 8
1332 if (x < 0 || x > 0x7FFFFFFF) {
1333 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1334 exit_cleanup(RERR_UNSUPPORTED);
1338 if (protocol_version < 30) {
1339 char * const s = b+4;
1341 #if SIZEOF_INT64 < 8
1344 if (x <= 0x7FFFFFFF && x >= 0) {
1350 SIVAL(s, 4, x >> 32);
1355 } else if (x < ((int32)1<<(3*8-1))) {
1356 b[0] = (char)(x >> 16);
1357 b[1] = (char)(x >> 8);
1360 } else if (x < ((int64)1<<(4*8-2))) {
1361 b[0] = (char)((x >> 24) | 0x80);
1362 b[1] = (char)(x >> 16);
1363 b[2] = (char)(x >> 8);
1366 #if SIZEOF_INT64 < 8
1369 b[1] = (char)(x >> 24);
1370 b[2] = (char)(x >> 16);
1371 b[3] = (char)(x >> 8);
1376 } else if (x < ((int64)1<<(5*8-3))) {
1377 b[0] = (char)((x >> 32) | 0xC0);
1378 b[1] = (char)(x >> 24);
1379 b[2] = (char)(x >> 16);
1380 b[3] = (char)(x >> 8);
1383 } else if (x < ((int64)1<<(6*8-4))) {
1384 b[0] = (char)((x >> 40) | 0xE0);
1385 b[1] = (char)(x >> 32);
1386 b[2] = (char)(x >> 24);
1387 b[3] = (char)(x >> 16);
1388 b[4] = (char)(x >> 8);
1391 } else if (x < ((int64)1<<(7*8-5))) {
1392 b[0] = (char)((x >> 48) | 0xF0);
1393 b[1] = (char)(x >> 40);
1394 b[2] = (char)(x >> 32);
1395 b[3] = (char)(x >> 24);
1396 b[4] = (char)(x >> 16);
1397 b[5] = (char)(x >> 8);
1400 } else if (x < ((int64)1<<(8*8-6))) {
1401 b[0] = (char)((x >> 56) | 0xF8);
1402 b[1] = (char)(x >> 48);
1403 b[2] = (char)(x >> 40);
1404 b[3] = (char)(x >> 32);
1405 b[4] = (char)(x >> 24);
1406 b[5] = (char)(x >> 16);
1407 b[6] = (char)(x >> 8);
1413 b[1] = (char)(x >> 56);
1414 b[2] = (char)(x >> 48);
1415 b[3] = (char)(x >> 40);
1416 b[4] = (char)(x >> 32);
1417 b[5] = (char)(x >> 24);
1418 b[6] = (char)(x >> 16);
1419 b[7] = (char)(x >> 8);
1426 void write_buf(int f, const char *buf, size_t len)
1431 /** Write a string to the connection */
1432 void write_sbuf(int f, const char *buf)
1434 writefd(f, buf, strlen(buf));
1437 void write_byte(int f, uchar c)
1439 writefd(f, (char *)&c, 1);
1442 void write_vstring(int f, const char *str, int len)
1444 uchar lenbuf[3], *lb = lenbuf;
1449 "attempting to send over-long vstring (%d > %d)\n",
1451 exit_cleanup(RERR_PROTOCOL);
1453 *lb++ = len / 0x100 + 0x80;
1457 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1459 writefd(f, str, len);
1463 * Read a line of up to @p maxlen characters into @p buf (not counting
1464 * the trailing null). Strips the (required) trailing newline and all
1467 * @return 1 for success; 0 for I/O error or truncation.
1469 int read_line(int f, char *buf, size_t maxlen)
1473 read_buf(f, buf, 1);
1478 if (buf[0] != '\r') {
1487 void io_printf(int fd, const char *format, ...)
1490 char buf[BIGPATHBUFLEN];
1493 va_start(ap, format);
1494 len = vsnprintf(buf, sizeof buf, format, ap);
1498 exit_cleanup(RERR_STREAMIO);
1500 if (len > (int)sizeof buf) {
1501 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1502 exit_cleanup(RERR_STREAMIO);
1505 write_sbuf(fd, buf);
1508 /** Setup for multiplexing a MSG_* stream with the data stream. */
1509 void io_start_multiplex_out(void)
1511 io_flush(NORMAL_FLUSH);
1512 io_start_buffering_out();
1513 io_multiplexing_out = 1;
1516 /** Setup for multiplexing a MSG_* stream with the data stream. */
1517 void io_start_multiplex_in(void)
1519 io_flush(NORMAL_FLUSH);
1520 io_start_buffering_in();
1521 io_multiplexing_in = 1;
1524 /** Write an message to the multiplexed data stream. */
1525 int io_multiplex_write(enum msgcode code, const char *buf, size_t len)
1527 if (!io_multiplexing_out)
1530 io_flush(NORMAL_FLUSH);
1531 stats.total_written += (len+4);
1532 mplex_write(code, buf, len);
1536 void close_multiplexing_in(void)
1538 io_multiplexing_in = 0;
1541 /** Stop output multiplexing. */
1542 void close_multiplexing_out(void)
1544 io_multiplexing_out = 0;
1547 void start_write_batch(int fd)
1549 write_stream_flags(batch_fd);
1551 /* Some communication has already taken place, but we don't
1552 * enable batch writing until here so that we can write a
1553 * canonical record of the communication even though the
1554 * actual communication so far depends on whether a daemon
1556 write_int(batch_fd, protocol_version);
1557 write_int(batch_fd, checksum_seed);
1560 write_batch_monitor_out = fd;
1562 write_batch_monitor_in = fd;
1565 void stop_write_batch(void)
1567 write_batch_monitor_out = -1;
1568 write_batch_monitor_in = -1;