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;
44 extern int incremental;
48 extern int read_batch;
49 extern int csum_length;
50 extern int checksum_seed;
51 extern int protocol_version;
52 extern int remove_source_files;
53 extern int preserve_hard_links;
54 extern char *filesfrom_host;
55 extern struct stats stats;
56 extern struct file_list *cur_flist, *first_flist;
58 const char phase_unknown[] = "unknown";
59 int ignore_timeout = 0;
63 /* Ignore an EOF error if non-zero. See whine_about_eof(). */
64 int kluge_around_eof = 0;
71 static int iobuf_f_in = -1;
72 static char *iobuf_in;
73 static size_t iobuf_in_siz;
74 static size_t iobuf_in_ndx;
75 static size_t iobuf_in_remaining;
77 static int iobuf_f_out = -1;
78 static char *iobuf_out;
79 static int iobuf_out_cnt;
81 int flist_forward_from = -1;
83 static int io_multiplexing_out;
84 static int io_multiplexing_in;
85 static time_t last_io_in;
86 static time_t last_io_out;
89 static int write_batch_monitor_in = -1;
90 static int write_batch_monitor_out = -1;
92 static int io_filesfrom_f_in = -1;
93 static int io_filesfrom_f_out = -1;
94 static char io_filesfrom_buf[2048];
95 static char *io_filesfrom_bp;
96 static char io_filesfrom_lastchar;
97 static int io_filesfrom_buflen;
98 static int defer_forwarding_messages = 0;
99 static int select_timeout = SELECT_TIMEOUT;
100 static int active_filecnt = 0;
101 static OFF_T active_bytecnt = 0;
103 static char int_byte_cnt[64] = {
104 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* (00 - 3F)/4 */
105 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* (40 - 7F)/4 */
106 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, /* (80 - BF)/4 */
107 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 8, 9, /* (C0 - FF)/4 */
110 static void readfd(int fd, char *buffer, size_t N);
111 static void writefd(int fd, const char *buf, size_t len);
112 static void writefd_unbuffered(int fd, const char *buf, size_t len);
113 static void decrement_active_files(int ndx);
114 static void decrement_flist_in_progress(int ndx, int redo);
116 struct flist_ndx_item {
117 struct flist_ndx_item *next;
121 struct flist_ndx_list {
122 struct flist_ndx_item *head, *tail;
125 static struct flist_ndx_list redo_list, hlink_list;
127 struct msg_list_item {
128 struct msg_list_item *next;
134 struct msg_list_item *head, *tail;
137 static struct msg_list msg2sndr;
139 static void flist_ndx_push(struct flist_ndx_list *lp, int ndx)
141 struct flist_ndx_item *item;
143 if (!(item = new(struct flist_ndx_item)))
144 out_of_memory("flist_ndx_push");
148 lp->tail->next = item;
154 static int flist_ndx_pop(struct flist_ndx_list *lp)
156 struct flist_ndx_item *next;
163 next = lp->head->next;
172 static void check_timeout(void)
176 if (!io_timeout || ignore_timeout)
180 last_io_in = time(NULL);
186 if (t - last_io_in >= io_timeout) {
187 if (!am_server && !am_daemon) {
188 rprintf(FERROR, "io timeout after %d seconds -- exiting\n",
189 (int)(t-last_io_in));
191 exit_cleanup(RERR_TIMEOUT);
195 /* Note the fds used for the main socket (which might really be a pipe
196 * for a local transfer, but we can ignore that). */
197 void io_set_sock_fds(int f_in, int f_out)
203 void set_io_timeout(int secs)
207 if (!io_timeout || io_timeout > SELECT_TIMEOUT)
208 select_timeout = SELECT_TIMEOUT;
210 select_timeout = io_timeout;
212 allowed_lull = read_batch ? 0 : (io_timeout + 1) / 2;
215 /* Setup the fd used to receive MSG_* messages. Only needed during the
216 * early stages of being a local sender (up through the sending of the
217 * file list) or when we're the generator (to fetch the messages from
219 void set_msg_fd_in(int fd)
224 /* Setup the fd used to send our MSG_* messages. Only needed when
225 * we're the receiver (to send our messages to the generator). */
226 void set_msg_fd_out(int fd)
229 set_nonblocking(msg_fd_out);
232 /* Add a message to the pending MSG_* list. */
233 static void msg_list_add(struct msg_list *lst, int code, const char *buf, int len)
235 struct msg_list_item *m;
236 int sz = len + 4 + sizeof m[0] - 1;
238 if (!(m = (struct msg_list_item *)new_array(char, sz)))
239 out_of_memory("msg_list_add");
242 SIVAL(m->buf, 0, ((code+MPLEX_BASE)<<24) | len);
243 memcpy(m->buf + 4, buf, len);
251 static void msg2sndr_flush(void)
253 while (msg2sndr.head && io_multiplexing_out) {
254 struct msg_list_item *m = msg2sndr.head;
255 if (!(msg2sndr.head = m->next))
256 msg2sndr.tail = NULL;
257 stats.total_written += m->len;
258 defer_forwarding_messages = 1;
259 writefd_unbuffered(sock_f_out, m->buf, m->len);
260 defer_forwarding_messages = 0;
265 /* Read a message from the MSG_* fd and handle it. This is called either
266 * during the early stages of being a local sender (up through the sending
267 * of the file list) or when we're the generator (to fetch the messages
268 * from the receiver). */
269 static void read_msg_fd(void)
273 struct file_list *flist;
277 /* Temporarily disable msg_fd_in. This is needed to avoid looping back
278 * to this routine from writefd_unbuffered(). */
281 defer_forwarding_messages++;
286 len = tag & 0xFFFFFF;
287 tag = (tag >> 24) - MPLEX_BASE;
291 if (len < 0 || len > 1 || !am_generator) {
293 rprintf(FERROR, "invalid message %d:%d [%s%s]\n",
294 tag, len, who_am_i(),
295 incremental ? "/incremental" : "");
296 exit_cleanup(RERR_STREAMIO);
299 readfd(fd, buf, len);
300 stats.total_read = read_longint(fd);
305 if (len != 4 || !am_generator)
308 if (remove_source_files)
309 decrement_active_files(IVAL(buf,0));
310 flist_ndx_push(&redo_list, IVAL(buf,0));
312 decrement_flist_in_progress(IVAL(buf,0), 1);
315 if (len != 4 || !am_generator || !incremental)
318 /* Read extra file list from receiver. */
319 assert(iobuf_in != NULL);
320 assert(iobuf_f_in == fd);
321 flist = recv_file_list(fd);
322 flist->parent_ndx = IVAL(buf,0);
325 if (len != 0 || !am_generator || !incremental)
330 if (len >= (int)sizeof buf || !am_generator)
332 readfd(fd, buf, len);
333 send_msg(MSG_DELETED, buf, len);
336 if (len != 4 || !am_generator)
338 readfd(fd, buf, len);
339 if (remove_source_files) {
340 decrement_active_files(IVAL(buf,0));
341 send_msg(MSG_SUCCESS, buf, len);
343 if (preserve_hard_links)
344 flist_ndx_push(&hlink_list, IVAL(buf,0));
346 decrement_flist_in_progress(IVAL(buf,0), 0);
349 if (len != 4 || !am_generator)
351 readfd(fd, buf, len);
353 decrement_flist_in_progress(IVAL(buf,0), 0);
359 if (tag == MSG_SOCKERR)
360 io_end_multiplex_out();
370 rwrite((enum logcode)tag, buf, n);
375 rprintf(FERROR, "unknown message %d:%d [%s]\n",
376 tag, len, who_am_i());
377 exit_cleanup(RERR_STREAMIO);
382 if (!--defer_forwarding_messages)
386 /* This is used by the generator to limit how many file transfers can
387 * be active at once when --remove-source-files is specified. Without
388 * this, sender-side deletions were mostly happening at the end. */
389 void increment_active_files(int ndx, int itemizing, enum logcode code)
391 /* TODO: tune these limits? */
392 while (active_filecnt >= (active_bytecnt >= 128*1024 ? 10 : 50)) {
393 #ifdef SUPPORT_HARD_LINKS
395 check_for_finished_hlinks(itemizing, code);
397 io_flush(NORMAL_FLUSH);
402 active_bytecnt += F_LENGTH(cur_flist->files[ndx]);
405 static void decrement_active_files(int ndx)
407 struct file_list *flist = flist_for_ndx(ndx);
408 assert(flist != NULL);
410 active_bytecnt -= F_LENGTH(flist->files[ndx - flist->ndx_start]);
413 static void decrement_flist_in_progress(int ndx, int redo)
415 struct file_list *flist = cur_flist ? cur_flist : first_flist;
417 while (ndx < flist->ndx_start) {
418 if (flist == first_flist) {
421 "Invalid file index: %d (%d - %d) [%s]\n",
422 ndx, first_flist->ndx_start,
423 first_flist->prev->ndx_start + first_flist->prev->count - 1,
425 exit_cleanup(RERR_PROTOCOL);
429 while (ndx >= flist->ndx_start + flist->count) {
430 if (!(flist = flist->next))
434 flist->in_progress--;
439 /* Write an message to a multiplexed stream. If this fails, rsync exits. */
440 static void mplex_write(int fd, enum msgcode code, const char *buf, size_t len)
445 SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
447 if (n > sizeof buffer - 4)
450 memcpy(buffer + 4, buf, n);
452 writefd_unbuffered(fd, buffer, n+4);
458 defer_forwarding_messages++;
459 writefd_unbuffered(fd, buf, len);
460 if (!--defer_forwarding_messages)
465 int send_msg(enum msgcode code, const char *buf, int len)
467 if (msg_fd_out < 0) {
468 if (!defer_forwarding_messages)
469 return io_multiplex_write(code, buf, len);
470 if (!io_multiplexing_out)
472 msg_list_add(&msg2sndr, code, buf, len);
475 mplex_write(msg_fd_out, code, buf, len);
479 void send_msg_int(enum msgcode code, int num)
482 SIVAL(numbuf, 0, num);
483 send_msg(code, numbuf, 4);
486 void wait_for_receiver(void)
488 io_flush(NORMAL_FLUSH);
492 int get_redo_num(void)
494 return flist_ndx_pop(&redo_list);
497 int get_hlink_num(void)
499 return flist_ndx_pop(&hlink_list);
503 * When we're the receiver and we have a local --files-from list of names
504 * that needs to be sent over the socket to the sender, we have to do two
505 * things at the same time: send the sender a list of what files we're
506 * processing and read the incoming file+info list from the sender. We do
507 * this by augmenting the read_timeout() function to copy this data. It
508 * uses the io_filesfrom_buf to read a block of data from f_in (when it is
509 * ready, since it might be a pipe) and then blast it out f_out (when it
510 * is ready to receive more data).
512 void io_set_filesfrom_fds(int f_in, int f_out)
514 io_filesfrom_f_in = f_in;
515 io_filesfrom_f_out = f_out;
516 io_filesfrom_bp = io_filesfrom_buf;
517 io_filesfrom_lastchar = '\0';
518 io_filesfrom_buflen = 0;
521 /* It's almost always an error to get an EOF when we're trying to read from the
522 * network, because the protocol is (for the most part) self-terminating.
524 * There is one case for the receiver when it is at the end of the transfer
525 * (hanging around reading any keep-alive packets that might come its way): if
526 * the sender dies before the generator's kill-signal comes through, we can end
527 * up here needing to loop until the kill-signal arrives. In this situation,
528 * kluge_around_eof will be < 0.
530 * There is another case for older protocol versions (< 24) where the module
531 * listing was not terminated, so we must ignore an EOF error in that case and
532 * exit. In this situation, kluge_around_eof will be > 0. */
533 static void whine_about_eof(int fd)
535 if (kluge_around_eof && fd == sock_f_in) {
537 if (kluge_around_eof > 0)
539 /* If we're still here after 10 seconds, exit with an error. */
540 for (i = 10*1000/20; i--; )
544 rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
545 "(%.0f bytes received so far) [%s]\n",
546 (double)stats.total_read, who_am_i());
548 exit_cleanup(RERR_STREAMIO);
552 * Read from a socket with I/O timeout. return the number of bytes
553 * read. If no bytes can be read then exit, never return a number <= 0.
555 * TODO: If the remote shell connection fails, then current versions
556 * actually report an "unexpected EOF" error here. Since it's a
557 * fairly common mistake to try to use rsh when ssh is required, we
558 * should trap that: if we fail to read any data at all, we should
559 * give a better explanation. We can tell whether the connection has
560 * started by looking e.g. at whether the remote version is known yet.
562 static int read_timeout(int fd, char *buf, size_t len)
566 io_flush(FULL_FLUSH);
569 /* until we manage to read *something* */
578 if (io_filesfrom_f_out >= 0) {
580 if (io_filesfrom_buflen == 0) {
581 if (io_filesfrom_f_in >= 0) {
582 FD_SET(io_filesfrom_f_in, &r_fds);
583 new_fd = io_filesfrom_f_in;
585 io_filesfrom_f_out = -1;
589 FD_SET(io_filesfrom_f_out, &w_fds);
590 new_fd = io_filesfrom_f_out;
596 tv.tv_sec = select_timeout;
601 count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
605 exit_cleanup(RERR_SOCKETIO);
610 if (io_filesfrom_f_out >= 0) {
611 if (io_filesfrom_buflen) {
612 if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
613 int l = write(io_filesfrom_f_out,
615 io_filesfrom_buflen);
617 if (!(io_filesfrom_buflen -= l))
618 io_filesfrom_bp = io_filesfrom_buf;
620 io_filesfrom_bp += l;
622 /* XXX should we complain? */
623 io_filesfrom_f_out = -1;
626 } else if (io_filesfrom_f_in >= 0) {
627 if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
628 int l = read(io_filesfrom_f_in,
630 sizeof io_filesfrom_buf);
632 /* Send end-of-file marker */
633 io_filesfrom_buf[0] = '\0';
634 io_filesfrom_buf[1] = '\0';
635 io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
636 io_filesfrom_f_in = -1;
639 char *s = io_filesfrom_buf + l;
640 /* Transform CR and/or LF into '\0' */
641 while (s-- > io_filesfrom_buf) {
642 if (*s == '\n' || *s == '\r')
646 if (!io_filesfrom_lastchar) {
647 /* Last buf ended with a '\0', so don't
648 * let this buf start with one. */
649 while (l && !*io_filesfrom_bp)
650 io_filesfrom_bp++, l--;
653 io_filesfrom_bp = io_filesfrom_buf;
655 char *f = io_filesfrom_bp;
658 /* Eliminate any multi-'\0' runs. */
660 if (!(*t++ = *f++)) {
661 while (f != eob && !*f)
665 io_filesfrom_lastchar = f[-1];
667 io_filesfrom_buflen = l;
673 if (!FD_ISSET(fd, &r_fds))
676 n = read(fd, buf, len);
680 whine_about_eof(fd); /* Doesn't return. */
681 if (errno == EINTR || errno == EWOULDBLOCK
685 /* Don't write errors on a dead socket. */
686 if (fd == sock_f_in) {
687 io_end_multiplex_out();
688 rsyserr(FSOCKERR, errno, "read error");
690 rsyserr(FERROR, errno, "read error");
691 exit_cleanup(RERR_STREAMIO);
698 if (fd == sock_f_in && io_timeout)
699 last_io_in = time(NULL);
706 * Read a line into the "fname" buffer (which must be at least MAXPATHLEN
709 int read_filesfrom_line(int fd, char *fname)
711 char ch, *s, *eob = fname + MAXPATHLEN - 1;
713 int reading_remotely = filesfrom_host != NULL;
714 int nulls = eol_nulls || reading_remotely;
719 cnt = read(fd, &ch, 1);
720 if (cnt < 0 && (errno == EWOULDBLOCK
721 || errno == EINTR || errno == EAGAIN)) {
728 tv.tv_sec = select_timeout;
730 if (!select(fd+1, &r_fds, NULL, &e_fds, &tv))
732 if (FD_ISSET(fd, &e_fds)) {
733 rsyserr(FINFO, errno,
734 "select exception on fd %d", fd);
740 if (nulls? !ch : (ch == '\r' || ch == '\n')) {
741 /* Skip empty lines if reading locally. */
742 if (!reading_remotely && s == fname)
752 if (*fname == '#' || *fname == ';')
758 int io_start_buffering_out(int f_out)
761 assert(f_out == iobuf_f_out);
764 if (!(iobuf_out = new_array(char, IO_BUFFER_SIZE)))
765 out_of_memory("io_start_buffering_out");
771 int io_start_buffering_in(int f_in)
774 assert(f_in == iobuf_f_in);
777 iobuf_in_siz = 2 * IO_BUFFER_SIZE;
778 if (!(iobuf_in = new_array(char, iobuf_in_siz)))
779 out_of_memory("io_start_buffering_in");
784 void io_end_buffering_in(void)
791 iobuf_in_remaining = 0;
795 void io_end_buffering_out(void)
799 io_flush(FULL_FLUSH);
805 void maybe_flush_socket(void)
807 if (iobuf_out && iobuf_out_cnt && time(NULL) - last_io_out >= 5)
808 io_flush(NORMAL_FLUSH);
811 void maybe_send_keepalive(void)
813 if (time(NULL) - last_io_out >= allowed_lull) {
814 if (!iobuf_out || !iobuf_out_cnt) {
815 if (protocol_version < 29)
816 return; /* there's nothing we can do */
817 if (protocol_version >= 30)
818 send_msg(MSG_NOOP, "", 0);
820 write_int(sock_f_out, cur_flist->count);
821 write_shortint(sock_f_out, ITEM_IS_NEW);
825 io_flush(NORMAL_FLUSH);
829 void start_flist_forward(int f_in)
831 assert(iobuf_out != NULL);
832 assert(iobuf_f_out == msg_fd_out);
833 flist_forward_from = f_in;
836 void stop_flist_forward()
838 flist_forward_from = -1;
839 io_flush(FULL_FLUSH);
843 * Continue trying to read len bytes - don't return until len has been
846 static void read_loop(int fd, char *buf, size_t len)
849 int n = read_timeout(fd, buf, len);
857 * Read from the file descriptor handling multiplexing - return number
860 * Never returns <= 0.
862 static int readfd_unbuffered(int fd, char *buf, size_t len)
866 char line[BIGPATHBUFLEN];
868 if (!iobuf_in || fd != iobuf_f_in)
869 return read_timeout(fd, buf, len);
871 if (!io_multiplexing_in && iobuf_in_remaining == 0) {
872 iobuf_in_remaining = read_timeout(fd, iobuf_in, iobuf_in_siz);
877 if (iobuf_in_remaining) {
878 len = MIN(len, iobuf_in_remaining);
879 memcpy(buf, iobuf_in + iobuf_in_ndx, len);
881 iobuf_in_remaining -= len;
886 read_loop(fd, line, 4);
889 msg_bytes = tag & 0xFFFFFF;
890 tag = (tag >> 24) - MPLEX_BASE;
894 if (msg_bytes > iobuf_in_siz) {
895 if (!(iobuf_in = realloc_array(iobuf_in, char,
897 out_of_memory("readfd_unbuffered");
898 iobuf_in_siz = msg_bytes;
900 read_loop(fd, iobuf_in, msg_bytes);
901 iobuf_in_remaining = msg_bytes;
906 maybe_send_keepalive();
911 read_loop(fd, line, msg_bytes);
912 io_error |= IVAL(line, 0);
915 if (msg_bytes >= sizeof line)
917 read_loop(fd, line, msg_bytes);
918 /* A directory name was sent with the trailing null */
919 if (msg_bytes > 0 && !line[msg_bytes-1])
920 log_delete(line, S_IFDIR);
922 line[msg_bytes] = '\0';
923 log_delete(line, S_IFREG);
927 if (msg_bytes != 4) {
929 rprintf(FERROR, "invalid multi-message %d:%ld [%s]\n",
930 tag, (long)msg_bytes, who_am_i());
931 exit_cleanup(RERR_STREAMIO);
933 read_loop(fd, line, msg_bytes);
934 successful_send(IVAL(line, 0));
939 read_loop(fd, line, msg_bytes);
940 send_msg_int(MSG_NO_SEND, IVAL(line, 0));
944 if (msg_bytes >= sizeof line) {
947 "multiplexing overflow %d:%ld [%s]\n",
948 tag, (long)msg_bytes, who_am_i());
949 exit_cleanup(RERR_STREAMIO);
951 read_loop(fd, line, msg_bytes);
952 rwrite((enum logcode)tag, line, msg_bytes);
955 rprintf(FERROR, "unexpected tag %d [%s]\n",
957 exit_cleanup(RERR_STREAMIO);
961 if (iobuf_in_remaining == 0)
962 io_flush(NORMAL_FLUSH);
967 /* Do a buffered read from fd. Don't return until all N bytes have
968 * been read. If all N can't be read then exit with an error. */
969 static void readfd(int fd, char *buffer, size_t N)
975 cnt = readfd_unbuffered(fd, buffer + total, N-total);
979 if (fd == write_batch_monitor_in) {
980 if ((size_t)write(batch_fd, buffer, total) != total)
981 exit_cleanup(RERR_FILEIO);
984 if (fd == flist_forward_from)
985 writefd(iobuf_f_out, buffer, total);
988 stats.total_read += total;
991 unsigned short read_shortint(int f)
995 return (UVAL(b, 1) << 8) + UVAL(b, 0);
998 int32 read_int(int f)
1005 #if SIZEOF_INT32 > 4
1006 if (num & (int32)0x80000000)
1007 num |= ~(int32)0xffffffff;
1012 int64 read_longint(int f)
1017 if (protocol_version < 30) {
1020 if ((int32)num != (int32)0xffffffff)
1023 #if SIZEOF_INT64 < 8
1024 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1025 exit_cleanup(RERR_UNSUPPORTED);
1028 num = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
1033 cnt = int_byte_cnt[CVAL(b, 0) / 4];
1034 #if SIZEOF_INT64 < 8
1035 if (cnt > 5 || (cnt == 5 && (CVAL(b,0)&0x3F || CVAL(b,1)&0x80))) {
1036 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1037 exit_cleanup(RERR_UNSUPPORTED);
1041 readfd(f, b + 3, cnt - 3);
1047 num = NVAL4(b, 0x80);
1050 num = NVAL5(b, 0xC0);
1052 #if SIZEOF_INT64 >= 8
1054 num = NVAL6(b, 0xE0);
1057 num = NVAL7(b, 0xF0);
1060 num = NVAL8(b, 0xF8);
1063 num = NVAL8(b+1, 0);
1067 exit_cleanup(RERR_PROTOCOL); /* impossible... */
1074 void read_buf(int f, char *buf, size_t len)
1079 void read_sbuf(int f, char *buf, size_t len)
1081 readfd(f, buf, len);
1085 uchar read_byte(int f)
1088 readfd(f, (char *)&c, 1);
1092 int read_vstring(int f, char *buf, int bufsize)
1094 int len = read_byte(f);
1097 len = (len & ~0x80) * 0x100 + read_byte(f);
1099 if (len >= bufsize) {
1100 rprintf(FERROR, "over-long vstring received (%d > %d)\n",
1106 readfd(f, buf, len);
1111 /* Populate a sum_struct with values from the socket. This is
1112 * called by both the sender and the receiver. */
1113 void read_sum_head(int f, struct sum_struct *sum)
1115 sum->count = read_int(f);
1116 if (sum->count < 0) {
1117 rprintf(FERROR, "Invalid checksum count %ld [%s]\n",
1118 (long)sum->count, who_am_i());
1119 exit_cleanup(RERR_PROTOCOL);
1121 sum->blength = read_int(f);
1122 if (sum->blength < 0 || sum->blength > MAX_BLOCK_SIZE) {
1123 rprintf(FERROR, "Invalid block length %ld [%s]\n",
1124 (long)sum->blength, who_am_i());
1125 exit_cleanup(RERR_PROTOCOL);
1127 sum->s2length = protocol_version < 27 ? csum_length : (int)read_int(f);
1128 if (sum->s2length < 0 || sum->s2length > MD4_SUM_LENGTH) {
1129 rprintf(FERROR, "Invalid checksum length %d [%s]\n",
1130 sum->s2length, who_am_i());
1131 exit_cleanup(RERR_PROTOCOL);
1133 sum->remainder = read_int(f);
1134 if (sum->remainder < 0 || sum->remainder > sum->blength) {
1135 rprintf(FERROR, "Invalid remainder length %ld [%s]\n",
1136 (long)sum->remainder, who_am_i());
1137 exit_cleanup(RERR_PROTOCOL);
1141 /* Send the values from a sum_struct over the socket. Set sum to
1142 * NULL if there are no checksums to send. This is called by both
1143 * the generator and the sender. */
1144 void write_sum_head(int f, struct sum_struct *sum)
1146 static struct sum_struct null_sum;
1151 write_int(f, sum->count);
1152 write_int(f, sum->blength);
1153 if (protocol_version >= 27)
1154 write_int(f, sum->s2length);
1155 write_int(f, sum->remainder);
1159 * Sleep after writing to limit I/O bandwidth usage.
1161 * @todo Rather than sleeping after each write, it might be better to
1162 * use some kind of averaging. The current algorithm seems to always
1163 * use a bit less bandwidth than specified, because it doesn't make up
1164 * for slow periods. But arguably this is a feature. In addition, we
1165 * ought to take the time used to write the data into account.
1167 * During some phases of big transfers (file FOO is uptodate) this is
1168 * called with a small bytes_written every time. As the kernel has to
1169 * round small waits up to guarantee that we actually wait at least the
1170 * requested number of microseconds, this can become grossly inaccurate.
1171 * We therefore keep track of the bytes we've written over time and only
1172 * sleep when the accumulated delay is at least 1 tenth of a second.
1174 static void sleep_for_bwlimit(int bytes_written)
1176 static struct timeval prior_tv;
1177 static long total_written = 0;
1178 struct timeval tv, start_tv;
1179 long elapsed_usec, sleep_usec;
1181 #define ONE_SEC 1000000L /* # of microseconds in a second */
1183 if (!bwlimit_writemax)
1186 total_written += bytes_written;
1188 gettimeofday(&start_tv, NULL);
1189 if (prior_tv.tv_sec) {
1190 elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
1191 + (start_tv.tv_usec - prior_tv.tv_usec);
1192 total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
1193 if (total_written < 0)
1197 sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
1198 if (sleep_usec < ONE_SEC / 10) {
1199 prior_tv = start_tv;
1203 tv.tv_sec = sleep_usec / ONE_SEC;
1204 tv.tv_usec = sleep_usec % ONE_SEC;
1205 select(0, NULL, NULL, NULL, &tv);
1207 gettimeofday(&prior_tv, NULL);
1208 elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
1209 + (prior_tv.tv_usec - start_tv.tv_usec);
1210 total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
1213 /* Write len bytes to the file descriptor fd, looping as necessary to get
1214 * the job done and also (in certain circumstances) reading any data on
1215 * msg_fd_in to avoid deadlock.
1217 * This function underlies the multiplexing system. The body of the
1218 * application never calls this function directly. */
1219 static void writefd_unbuffered(int fd, const char *buf, size_t len)
1221 size_t n, total = 0;
1222 fd_set w_fds, r_fds, e_fds;
1223 int maxfd, count, cnt, using_r_fds;
1224 int defer_save = defer_forwarding_messages;
1228 defer_forwarding_messages = 1;
1230 while (total < len) {
1237 if (msg_fd_in >= 0) {
1239 FD_SET(msg_fd_in, &r_fds);
1240 if (msg_fd_in > maxfd)
1246 tv.tv_sec = select_timeout;
1250 count = select(maxfd + 1, using_r_fds ? &r_fds : NULL,
1251 &w_fds, &e_fds, &tv);
1254 if (count < 0 && errno == EBADF)
1255 exit_cleanup(RERR_SOCKETIO);
1260 if (FD_ISSET(fd, &e_fds)) {
1261 rsyserr(FINFO, errno,
1262 "select exception on fd %d", fd);
1265 if (using_r_fds && FD_ISSET(msg_fd_in, &r_fds))
1268 if (!FD_ISSET(fd, &w_fds))
1272 if (bwlimit_writemax && n > bwlimit_writemax)
1273 n = bwlimit_writemax;
1274 cnt = write(fd, buf + total, n);
1280 if (errno == EWOULDBLOCK || errno == EAGAIN) {
1286 /* Don't try to write errors back across the stream. */
1287 if (fd == sock_f_out)
1288 io_end_multiplex_out();
1289 rsyserr(FERROR, errno,
1290 "writefd_unbuffered failed to write %ld bytes [%s]",
1291 (long)len, who_am_i());
1292 /* If the other side is sending us error messages, try
1293 * to grab any messages they sent before they died. */
1294 while (fd == sock_f_out && io_multiplexing_in) {
1297 readfd_unbuffered(sock_f_in, io_filesfrom_buf,
1298 sizeof io_filesfrom_buf);
1300 exit_cleanup(RERR_STREAMIO);
1304 defer_forwarding_messages = 1;
1306 if (fd == sock_f_out) {
1307 if (io_timeout || am_generator)
1308 last_io_out = time(NULL);
1309 sleep_for_bwlimit(cnt);
1314 if (!(defer_forwarding_messages = defer_save))
1318 void io_flush(int flush_it_all)
1320 if (flush_it_all && !defer_forwarding_messages)
1323 if (!iobuf_out_cnt || no_flush)
1326 if (io_multiplexing_out)
1327 mplex_write(sock_f_out, MSG_DATA, iobuf_out, iobuf_out_cnt);
1329 writefd_unbuffered(iobuf_f_out, iobuf_out, iobuf_out_cnt);
1333 static void writefd(int fd, const char *buf, size_t len)
1335 if (fd == sock_f_out)
1336 stats.total_written += len;
1338 if (fd == write_batch_monitor_out) {
1339 if ((size_t)write(batch_fd, buf, len) != len)
1340 exit_cleanup(RERR_FILEIO);
1343 if (!iobuf_out || fd != iobuf_f_out) {
1344 writefd_unbuffered(fd, buf, len);
1349 int n = MIN((int)len, IO_BUFFER_SIZE - iobuf_out_cnt);
1351 memcpy(iobuf_out+iobuf_out_cnt, buf, n);
1357 if (iobuf_out_cnt == IO_BUFFER_SIZE)
1358 io_flush(NORMAL_FLUSH);
1362 void write_shortint(int f, unsigned short x)
1366 b[1] = (char)(x >> 8);
1370 void write_int(int f, int32 x)
1378 * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
1379 * 64-bit types on this platform.
1381 void write_longint(int f, int64 x)
1385 #if SIZEOF_INT64 < 8
1386 if (x < 0 || x > 0x7FFFFFFF) {
1387 rprintf(FERROR, "Integer overflow: attempted 64-bit offset\n");
1388 exit_cleanup(RERR_UNSUPPORTED);
1392 if (protocol_version < 30) {
1393 char * const s = b+4;
1395 #if SIZEOF_INT64 < 8
1398 if (x <= 0x7FFFFFFF && x >= 0) {
1404 SIVAL(s, 4, x >> 32);
1409 } else if (x < ((int32)1<<(3*8-1))) {
1410 b[0] = (char)(x >> 16);
1411 b[1] = (char)(x >> 8);
1414 } else if (x < ((int64)1<<(4*8-2))) {
1415 b[0] = (char)((x >> 24) | 0x80);
1416 b[1] = (char)(x >> 16);
1417 b[2] = (char)(x >> 8);
1420 #if SIZEOF_INT64 < 8
1423 b[1] = (char)(x >> 24);
1424 b[2] = (char)(x >> 16);
1425 b[3] = (char)(x >> 8);
1430 } else if (x < ((int64)1<<(5*8-3))) {
1431 b[0] = (char)((x >> 32) | 0xC0);
1432 b[1] = (char)(x >> 24);
1433 b[2] = (char)(x >> 16);
1434 b[3] = (char)(x >> 8);
1437 } else if (x < ((int64)1<<(6*8-4))) {
1438 b[0] = (char)((x >> 40) | 0xE0);
1439 b[1] = (char)(x >> 32);
1440 b[2] = (char)(x >> 24);
1441 b[3] = (char)(x >> 16);
1442 b[4] = (char)(x >> 8);
1445 } else if (x < ((int64)1<<(7*8-5))) {
1446 b[0] = (char)((x >> 48) | 0xF0);
1447 b[1] = (char)(x >> 40);
1448 b[2] = (char)(x >> 32);
1449 b[3] = (char)(x >> 24);
1450 b[4] = (char)(x >> 16);
1451 b[5] = (char)(x >> 8);
1454 } else if (x < ((int64)1<<(8*8-6))) {
1455 b[0] = (char)((x >> 56) | 0xF8);
1456 b[1] = (char)(x >> 48);
1457 b[2] = (char)(x >> 40);
1458 b[3] = (char)(x >> 32);
1459 b[4] = (char)(x >> 24);
1460 b[5] = (char)(x >> 16);
1461 b[6] = (char)(x >> 8);
1467 b[1] = (char)(x >> 56);
1468 b[2] = (char)(x >> 48);
1469 b[3] = (char)(x >> 40);
1470 b[4] = (char)(x >> 32);
1471 b[5] = (char)(x >> 24);
1472 b[6] = (char)(x >> 16);
1473 b[7] = (char)(x >> 8);
1480 void write_buf(int f, const char *buf, size_t len)
1485 /** Write a string to the connection */
1486 void write_sbuf(int f, const char *buf)
1488 writefd(f, buf, strlen(buf));
1491 void write_byte(int f, uchar c)
1493 writefd(f, (char *)&c, 1);
1496 void write_vstring(int f, const char *str, int len)
1498 uchar lenbuf[3], *lb = lenbuf;
1503 "attempting to send over-long vstring (%d > %d)\n",
1505 exit_cleanup(RERR_PROTOCOL);
1507 *lb++ = len / 0x100 + 0x80;
1511 writefd(f, (char*)lenbuf, lb - lenbuf + 1);
1513 writefd(f, str, len);
1516 /* Send a file-list index using a byte-reduction method. */
1517 void write_ndx(int f, int32 ndx)
1519 static int32 prev_positive = -1, prev_negative = 1;
1520 int32 diff, cnt = 0;
1523 if (protocol_version < 30 || read_batch) {
1528 /* Send NDX_DONE as a single-byte 0 with no side effects. Send
1529 * negative nums as a positive after sending a leading 0xFF. */
1531 diff = ndx - prev_positive;
1532 prev_positive = ndx;
1533 } else if (ndx == NDX_DONE) {
1538 b[cnt++] = (char)0xFF;
1540 diff = ndx - prev_negative;
1541 prev_negative = ndx;
1544 /* A diff of 1 - 253 is sent as a one-byte diff; a diff of 254 - 32767
1545 * or 0 is sent as a 0xFE + a two-byte diff; otherwise we send 0xFE
1546 * & all 4 bytes of the (non-negative) num with the high-bit set. */
1547 if (diff < 0xFE && diff > 0)
1548 b[cnt++] = (char)diff;
1549 else if (diff < 0 || diff > 0x7FFF) {
1550 b[cnt++] = (char)0xFE;
1551 b[cnt++] = (char)((ndx >> 24) | 0x80);
1552 b[cnt++] = (char)(ndx >> 16);
1553 b[cnt++] = (char)(ndx >> 8);
1554 b[cnt++] = (char)ndx;
1556 b[cnt++] = (char)0xFE;
1557 b[cnt++] = (char)(diff >> 8);
1558 b[cnt++] = (char)diff;
1563 /* Receive a file-list index using a byte-reduction method. */
1564 int32 read_ndx(int f)
1566 static int32 prev_positive = -1, prev_negative = 1;
1567 int32 *prev_ptr, num;
1570 if (protocol_version < 30)
1574 if (CVAL(b, 0) == 0xFF) {
1576 prev_ptr = &prev_negative;
1577 } else if (CVAL(b, 0) == 0)
1580 prev_ptr = &prev_positive;
1581 if (CVAL(b, 0) == 0xFE) {
1583 if (CVAL(b, 0) & 0x80) {
1585 num = NVAL4(b, 0x80);
1587 num = NVAL2(b, 0) + *prev_ptr;
1589 num = CVAL(b, 0) + *prev_ptr;
1591 if (prev_ptr == &prev_negative)
1597 * Read a line of up to @p maxlen characters into @p buf (not counting
1598 * the trailing null). Strips the (required) trailing newline and all
1601 * @return 1 for success; 0 for I/O error or truncation.
1603 int read_line(int f, char *buf, size_t maxlen)
1607 read_buf(f, buf, 1);
1612 if (buf[0] != '\r') {
1621 void io_printf(int fd, const char *format, ...)
1624 char buf[BIGPATHBUFLEN];
1627 va_start(ap, format);
1628 len = vsnprintf(buf, sizeof buf, format, ap);
1632 exit_cleanup(RERR_STREAMIO);
1634 if (len > (int)sizeof buf) {
1635 rprintf(FERROR, "io_printf() was too long for the buffer.\n");
1636 exit_cleanup(RERR_STREAMIO);
1639 write_sbuf(fd, buf);
1642 /** Setup for multiplexing a MSG_* stream with the data stream. */
1643 void io_start_multiplex_out(void)
1645 io_flush(NORMAL_FLUSH);
1646 io_start_buffering_out(sock_f_out);
1647 io_multiplexing_out = 1;
1650 /** Setup for multiplexing a MSG_* stream with the data stream. */
1651 void io_start_multiplex_in(void)
1653 io_flush(NORMAL_FLUSH);
1654 io_start_buffering_in(sock_f_in);
1655 io_multiplexing_in = 1;
1658 /** Write an message to the multiplexed data stream. */
1659 int io_multiplex_write(enum msgcode code, const char *buf, size_t len)
1661 if (!io_multiplexing_out)
1663 io_flush(NORMAL_FLUSH);
1664 stats.total_written += (len+4);
1665 mplex_write(sock_f_out, code, buf, len);
1669 void io_end_multiplex_in(void)
1671 io_multiplexing_in = 0;
1672 io_end_buffering_in();
1675 /** Stop output multiplexing. */
1676 void io_end_multiplex_out(void)
1678 io_multiplexing_out = 0;
1679 io_end_buffering_out();
1682 void start_write_batch(int fd)
1684 /* Some communication has already taken place, but we don't
1685 * enable batch writing until here so that we can write a
1686 * canonical record of the communication even though the
1687 * actual communication so far depends on whether a daemon
1689 write_int(batch_fd, protocol_version);
1690 write_int(batch_fd, checksum_seed);
1693 write_batch_monitor_out = fd;
1695 write_batch_monitor_in = fd;
1698 void stop_write_batch(void)
1700 write_batch_monitor_out = -1;
1701 write_batch_monitor_in = -1;