-/*
- Copyright (C) Andrew Tridgell 1996
- Copyright (C) Paul Mackerras 1996
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
+/* -*- c-file-style: "linux" -*-
+ *
+ * Copyright (C) 1996-2001 by Andrew Tridgell
+ * Copyright (C) Paul Mackerras 1996
+ * Copyright (C) 2001, 2002 by Martin Pool <mbp@samba.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/**
+ * @file io.c
+ *
+ * Socket and pipe I/O utilities used in rsync.
+ *
+ * rsync provides its own multiplexing system, which is used to send
+ * stderr and stdout over a single socket. We need this because
+ * stdout normally carries the binary data stream, and stderr all our
+ * error messages.
+ *
+ * For historical reasons this is off during the start of the
+ * connection, but it's switched on quite early using
+ * io_start_multiplex_out() and io_start_multiplex_in().
+ **/
-/*
- Utilities used in rsync
-
- tridge, June 1996
- */
#include "rsync.h"
-/* if no timeout is specified then use a 60 second select timeout */
+/** If no timeout is specified then use a 60 second select timeout */
#define SELECT_TIMEOUT 60
static int io_multiplexing_out;
static int io_multiplexing_in;
-static int multiplex_in_fd;
-static int multiplex_out_fd;
+static int multiplex_in_fd = -1;
+static int multiplex_out_fd = -1;
static time_t last_io;
-static int eof_error=1;
+static int no_flush;
+
+extern int bwlimit;
+extern size_t bwlimit_writemax;
extern int verbose;
extern int io_timeout;
+extern int am_server;
+extern int am_daemon;
+extern int am_sender;
+extern int eol_nulls;
+extern char *remote_filesfrom_file;
extern struct stats stats;
-static int buffer_f_in = -1;
+const char phase_unknown[] = "unknown";
+int select_timeout = SELECT_TIMEOUT;
+
+/**
+ * The connection might be dropped at some point; perhaps because the
+ * remote instance crashed. Just giving the offset on the stream is
+ * not very helpful. So instead we try to make io_phase_name point to
+ * something useful.
+ *
+ * For buffered/multiplexed I/O these names will be somewhat
+ * approximate; perhaps for ease of support we would rather make the
+ * buffer always flush when a single application-level I/O finishes.
+ *
+ * @todo Perhaps we want some simple stack functionality, but there's
+ * no need to overdo it.
+ **/
+const char *io_write_phase = phase_unknown;
+const char *io_read_phase = phase_unknown;
+
+/** Ignore EOF errors while reading a module listing if the remote
+ version is 24 or less. */
+int kludge_around_eof = False;
+
+int msg_fd_in = -1;
+int msg_fd_out = -1;
+
+static int io_filesfrom_f_in = -1;
+static int io_filesfrom_f_out = -1;
+static char io_filesfrom_buf[2048];
+static char *io_filesfrom_bp;
+static char io_filesfrom_lastchar;
+static int io_filesfrom_buflen;
+
+static void read_loop(int fd, char *buf, size_t len);
+
+struct redo_list {
+ struct redo_list *next;
+ int num;
+};
+
+static struct redo_list *redo_list_head;
+static struct redo_list *redo_list_tail;
+
+struct msg_list {
+ struct msg_list *next;
+ char *buf;
+ int len;
+};
+
+static struct msg_list *msg_list_head;
+static struct msg_list *msg_list_tail;
-void setup_readbuffer(int f_in)
+static void redo_list_add(int num)
{
- buffer_f_in = f_in;
+ struct redo_list *rl;
+
+ if (!(rl = new(struct redo_list)))
+ exit_cleanup(RERR_MALLOC);
+ rl->next = NULL;
+ rl->num = num;
+ if (redo_list_tail)
+ redo_list_tail->next = rl;
+ else
+ redo_list_head = rl;
+ redo_list_tail = rl;
}
static void check_timeout(void)
{
time_t t;
-
- if (!io_timeout) return;
+
+ if (!io_timeout)
+ return;
if (!last_io) {
last_io = time(NULL);
t = time(NULL);
if (last_io && io_timeout && (t-last_io) >= io_timeout) {
- rprintf(FERROR,"io timeout after %d second - exiting\n",
- (int)(t-last_io));
- exit_cleanup(1);
+ if (!am_server && !am_daemon) {
+ rprintf(FERROR, "io timeout after %d seconds - exiting\n",
+ (int)(t-last_io));
+ }
+ exit_cleanup(RERR_TIMEOUT);
}
}
+/** Setup the fd used to receive MSG_* messages. Only needed when
+ * we're the generator because the sender and receiver both use the
+ * multiplexed I/O setup. */
+void set_msg_fd_in(int fd)
+{
+ msg_fd_in = fd;
+}
-static char *read_buffer;
-static char *read_buffer_p;
-static int read_buffer_len;
-static int read_buffer_size;
-static int no_flush;
-static int no_flush_read;
+/** Setup the fd used to send our MSG_* messages. Only needed when
+ * we're the receiver because the generator and the sender both use
+ * the multiplexed I/O setup. */
+void set_msg_fd_out(int fd)
+{
+ msg_fd_out = fd;
+ set_nonblocking(msg_fd_out);
+}
+
+/* Add a message to the pending MSG_* list. */
+static void msg_list_add(int code, char *buf, int len)
+{
+ struct msg_list *ml;
+
+ if (!(ml = new(struct msg_list)))
+ exit_cleanup(RERR_MALLOC);
+ ml->next = NULL;
+ if (!(ml->buf = new_array(char, len+4)))
+ exit_cleanup(RERR_MALLOC);
+ SIVAL(ml->buf, 0, ((code+MPLEX_BASE)<<24) | len);
+ memcpy(ml->buf+4, buf, len);
+ ml->len = len+4;
+ if (msg_list_tail)
+ msg_list_tail->next = ml;
+ else
+ msg_list_head = ml;
+ msg_list_tail = ml;
+}
+
+void send_msg(enum msgcode code, char *buf, int len)
+{
+ msg_list_add(code, buf, len);
+ msg_list_push(NORMAL_FLUSH);
+}
+
+/** Read a message from the MSG_* fd and dispatch it. This is only
+ * called by the generator. */
+static void read_msg_fd(void)
+{
+ char buf[2048];
+ size_t n;
+ int fd = msg_fd_in;
+ int tag, len;
+
+ /* Temporarily disable msg_fd_in. This is needed to avoid looping back
+ * to this routine from read_timeout() and writefd_unbuffered(). */
+ msg_fd_in = -1;
+
+ read_loop(fd, buf, 4);
+ tag = IVAL(buf, 0);
+
+ len = tag & 0xFFFFFF;
+ tag = (tag >> 24) - MPLEX_BASE;
+
+ switch (tag) {
+ case MSG_DONE:
+ if (len != 0) {
+ rprintf(FERROR, "invalid message %d:%d\n", tag, len);
+ exit_cleanup(RERR_STREAMIO);
+ }
+ redo_list_add(-1);
+ break;
+ case MSG_REDO:
+ if (len != 4) {
+ rprintf(FERROR, "invalid message %d:%d\n", tag, len);
+ exit_cleanup(RERR_STREAMIO);
+ }
+ read_loop(fd, buf, 4);
+ redo_list_add(IVAL(buf,0));
+ break;
+ case MSG_INFO:
+ case MSG_ERROR:
+ case MSG_LOG:
+ while (len) {
+ n = len;
+ if (n >= sizeof buf)
+ n = sizeof buf - 1;
+ read_loop(fd, buf, n);
+ rwrite((enum logcode)tag, buf, n);
+ len -= n;
+ }
+ break;
+ default:
+ rprintf(FERROR, "unknown message %d:%d\n", tag, len);
+ exit_cleanup(RERR_STREAMIO);
+ }
-/* read from a socket with IO timeout. return the number of
- bytes read. If no bytes can be read then exit, never return
- a number <= 0 */
-static int read_timeout(int fd, char *buf, int len)
+ msg_fd_in = fd;
+}
+
+/* Try to push messages off the list onto the wire. If we leave with more
+ * to do, return 0. On error, return -1. If everything flushed, return 1.
+ * This is only active in the receiver. */
+int msg_list_push(int flush_it_all)
+{
+ static int written = 0;
+ struct timeval tv;
+ fd_set fds;
+
+ if (msg_fd_out < 0)
+ return -1;
+
+ while (msg_list_head) {
+ struct msg_list *ml = msg_list_head;
+ int n = write(msg_fd_out, ml->buf + written, ml->len - written);
+ if (n < 0) {
+ if (errno == EINTR)
+ continue;
+ if (errno != EWOULDBLOCK && errno != EAGAIN)
+ return -1;
+ if (!flush_it_all)
+ return 0;
+ FD_ZERO(&fds);
+ FD_SET(msg_fd_out, &fds);
+ tv.tv_sec = select_timeout;
+ tv.tv_usec = 0;
+ if (!select(msg_fd_out+1, NULL, &fds, NULL, &tv))
+ check_timeout();
+ } else if ((written += n) == ml->len) {
+ free(ml->buf);
+ msg_list_head = ml->next;
+ if (!msg_list_head)
+ msg_list_tail = NULL;
+ free(ml);
+ written = 0;
+ }
+ }
+ return 1;
+}
+
+int get_redo_num(void)
{
- int n, ret=0;
+ struct redo_list *next;
+ int num;
+
+ while (!redo_list_head)
+ read_msg_fd();
- no_flush_read++;
- io_flush();
- no_flush_read--;
+ num = redo_list_head->num;
+ next = redo_list_head->next;
+ free(redo_list_head);
+ redo_list_head = next;
+ if (!next)
+ redo_list_tail = NULL;
+
+ return num;
+}
+
+/**
+ * When we're the receiver and we have a local --files-from list of names
+ * that needs to be sent over the socket to the sender, we have to do two
+ * things at the same time: send the sender a list of what files we're
+ * processing and read the incoming file+info list from the sender. We do
+ * this by augmenting the read_timeout() function to copy this data. It
+ * uses the io_filesfrom_buf to read a block of data from f_in (when it is
+ * ready, since it might be a pipe) and then blast it out f_out (when it
+ * is ready to receive more data).
+ */
+void io_set_filesfrom_fds(int f_in, int f_out)
+{
+ io_filesfrom_f_in = f_in;
+ io_filesfrom_f_out = f_out;
+ io_filesfrom_bp = io_filesfrom_buf;
+ io_filesfrom_lastchar = '\0';
+ io_filesfrom_buflen = 0;
+}
+
+/**
+ * It's almost always an error to get an EOF when we're trying to read
+ * from the network, because the protocol is self-terminating.
+ *
+ * However, there is one unfortunate cases where it is not, which is
+ * rsync <2.4.6 sending a list of modules on a server, since the list
+ * is terminated by closing the socket. So, for the section of the
+ * program where that is a problem (start_socket_client),
+ * kludge_around_eof is True and we just exit.
+ */
+static void whine_about_eof(void)
+{
+ if (kludge_around_eof)
+ exit_cleanup(0);
+
+ rprintf(FERROR, RSYNC_NAME ": connection unexpectedly closed "
+ "(%.0f bytes read so far)\n",
+ (double)stats.total_read);
+
+ exit_cleanup(RERR_STREAMIO);
+}
+
+
+static void die_from_readerr(int err)
+{
+ /* this prevents us trying to write errors on a dead socket */
+ io_multiplexing_close();
+
+ rsyserr(FERROR, err, "read error");
+ exit_cleanup(RERR_STREAMIO);
+}
+
+
+/**
+ * Read from a socket with I/O timeout. return the number of bytes
+ * read. If no bytes can be read then exit, never return a number <= 0.
+ *
+ * TODO: If the remote shell connection fails, then current versions
+ * actually report an "unexpected EOF" error here. Since it's a
+ * fairly common mistake to try to use rsh when ssh is required, we
+ * should trap that: if we fail to read any data at all, we should
+ * give a better explanation. We can tell whether the connection has
+ * started by looking e.g. at whether the remote version is known yet.
+ */
+static int read_timeout(int fd, char *buf, size_t len)
+{
+ int n, ret = 0;
+
+ io_flush(NORMAL_FLUSH);
while (ret == 0) {
- fd_set fds;
+ /* until we manage to read *something* */
+ fd_set r_fds, w_fds;
struct timeval tv;
+ int maxfd = fd;
+ int count;
+
+ FD_ZERO(&r_fds);
+ FD_ZERO(&w_fds);
+ FD_SET(fd, &r_fds);
+ if (msg_fd_in >= 0) {
+ FD_SET(msg_fd_in, &r_fds);
+ if (msg_fd_in > maxfd)
+ maxfd = msg_fd_in;
+ } else if (msg_list_head) {
+ FD_SET(msg_fd_out, &w_fds);
+ if (msg_fd_out > maxfd)
+ maxfd = msg_fd_out;
+ }
+ if (io_filesfrom_f_out >= 0) {
+ int new_fd;
+ if (io_filesfrom_buflen == 0) {
+ if (io_filesfrom_f_in >= 0) {
+ FD_SET(io_filesfrom_f_in, &r_fds);
+ new_fd = io_filesfrom_f_in;
+ } else {
+ io_filesfrom_f_out = -1;
+ new_fd = -1;
+ }
+ } else {
+ FD_SET(io_filesfrom_f_out, &w_fds);
+ new_fd = io_filesfrom_f_out;
+ }
+ if (new_fd > maxfd)
+ maxfd = new_fd;
+ }
- FD_ZERO(&fds);
- FD_SET(fd, &fds);
- tv.tv_sec = io_timeout?io_timeout:SELECT_TIMEOUT;
+ tv.tv_sec = select_timeout;
tv.tv_usec = 0;
- if (select(fd+1, &fds, NULL, NULL, &tv) != 1) {
- check_timeout();
- continue;
- }
+ errno = 0;
- n = read(fd, buf, len);
+ count = select(maxfd + 1, &r_fds, &w_fds, NULL, &tv);
- if (n > 0) {
- stats.total_read += n;
- buf += n;
- len -= n;
- ret += n;
- if (io_timeout)
- last_io = time(NULL);
+ if (count <= 0) {
+ if (errno == EBADF)
+ exit_cleanup(RERR_SOCKETIO);
+ check_timeout();
continue;
}
- if (n == -1 && errno == EINTR) {
- continue;
+ if (msg_fd_in >= 0 && FD_ISSET(msg_fd_in, &r_fds))
+ read_msg_fd();
+ else if (msg_list_head && FD_ISSET(msg_fd_out, &w_fds))
+ msg_list_push(NORMAL_FLUSH);
+
+ if (io_filesfrom_f_out >= 0) {
+ if (io_filesfrom_buflen) {
+ if (FD_ISSET(io_filesfrom_f_out, &w_fds)) {
+ int l = write(io_filesfrom_f_out,
+ io_filesfrom_bp,
+ io_filesfrom_buflen);
+ if (l > 0) {
+ if (!(io_filesfrom_buflen -= l))
+ io_filesfrom_bp = io_filesfrom_buf;
+ else
+ io_filesfrom_bp += l;
+ } else {
+ /* XXX should we complain? */
+ io_filesfrom_f_out = -1;
+ }
+ }
+ } else if (io_filesfrom_f_in >= 0) {
+ if (FD_ISSET(io_filesfrom_f_in, &r_fds)) {
+ int l = read(io_filesfrom_f_in,
+ io_filesfrom_buf,
+ sizeof io_filesfrom_buf);
+ if (l <= 0) {
+ /* Send end-of-file marker */
+ io_filesfrom_buf[0] = '\0';
+ io_filesfrom_buf[1] = '\0';
+ io_filesfrom_buflen = io_filesfrom_lastchar? 2 : 1;
+ io_filesfrom_f_in = -1;
+ } else {
+ if (!eol_nulls) {
+ char *s = io_filesfrom_buf + l;
+ /* Transform CR and/or LF into '\0' */
+ while (s-- > io_filesfrom_buf) {
+ if (*s == '\n' || *s == '\r')
+ *s = '\0';
+ }
+ }
+ if (!io_filesfrom_lastchar) {
+ /* Last buf ended with a '\0', so don't
+ * let this buf start with one. */
+ while (l && !*io_filesfrom_bp)
+ io_filesfrom_bp++, l--;
+ }
+ if (!l)
+ io_filesfrom_bp = io_filesfrom_buf;
+ else {
+ char *f = io_filesfrom_bp;
+ char *t = f;
+ char *eob = f + l;
+ /* Eliminate any multi-'\0' runs. */
+ while (f != eob) {
+ if (!(*t++ = *f++)) {
+ while (f != eob && !*f)
+ f++, l--;
+ }
+ }
+ io_filesfrom_lastchar = f[-1];
+ }
+ io_filesfrom_buflen = l;
+ }
+ }
+ }
}
- if (n == -1 &&
- (errno == EAGAIN || errno == EWOULDBLOCK)) {
- /* this shouldn't happen, if it does then
- sleep for a short time to prevent us
- chewing too much CPU */
- u_sleep(100);
+ if (!FD_ISSET(fd, &r_fds))
continue;
- }
- if (n == 0) {
- if (eof_error) {
- rprintf(FERROR,"unexpected EOF in read_timeout\n");
- }
- exit_cleanup(1);
+ n = read(fd, buf, len);
+
+ if (n <= 0) {
+ if (n == 0)
+ whine_about_eof(); /* Doesn't return. */
+ if (errno == EINTR || errno == EWOULDBLOCK
+ || errno == EAGAIN)
+ continue;
+ die_from_readerr(errno); /* Doesn't return. */
}
- rprintf(FERROR,"read error: %s\n", strerror(errno));
- exit_cleanup(1);
+ buf += n;
+ len -= n;
+ ret += n;
+ if (io_timeout)
+ last_io = time(NULL);
}
return ret;
}
-/* continue trying to read len bytes - don't return until len
- has been read */
-static void read_loop(int fd, char *buf, int len)
+/**
+ * Read a line into the "fname" buffer (which must be at least MAXPATHLEN
+ * characters long).
+ */
+int read_filesfrom_line(int fd, char *fname)
+{
+ char ch, *s, *eob = fname + MAXPATHLEN - 1;
+ int cnt;
+ int reading_remotely = remote_filesfrom_file != NULL;
+ int nulls = eol_nulls || reading_remotely;
+
+ start:
+ s = fname;
+ while (1) {
+ cnt = read(fd, &ch, 1);
+ if (cnt < 0 && (errno == EWOULDBLOCK
+ || errno == EINTR || errno == EAGAIN)) {
+ struct timeval tv;
+ fd_set fds;
+ FD_ZERO(&fds);
+ FD_SET(fd, &fds);
+ tv.tv_sec = select_timeout;
+ tv.tv_usec = 0;
+ if (!select(fd+1, &fds, NULL, NULL, &tv))
+ check_timeout();
+ continue;
+ }
+ if (cnt != 1)
+ break;
+ if (nulls? !ch : (ch == '\r' || ch == '\n')) {
+ /* Skip empty lines if reading locally. */
+ if (!reading_remotely && s == fname)
+ continue;
+ break;
+ }
+ if (s < eob)
+ *s++ = ch;
+ }
+ *s = '\0';
+
+ /* Dump comments. */
+ if (*fname == '#' || *fname == ';')
+ goto start;
+
+ return s - fname;
+}
+
+
+/**
+ * Continue trying to read len bytes - don't return until len has been
+ * read.
+ **/
+static void read_loop(int fd, char *buf, size_t len)
{
while (len) {
int n = read_timeout(fd, buf, len);
}
}
-/* read from the file descriptor handling multiplexing -
- return number of bytes read
- never return <= 0 */
-static int read_unbuffered(int fd, char *buf, int len)
+
+/**
+ * Read from the file descriptor handling multiplexing - return number
+ * of bytes read.
+ *
+ * Never returns <= 0.
+ */
+static int readfd_unbuffered(int fd, char *buf, size_t len)
{
- static int remaining;
- char ibuf[4];
- int tag, ret=0;
+ static size_t remaining;
+ int tag, ret = 0;
char line[1024];
+ static char *buffer;
+ static size_t bufferIdx = 0;
+ static size_t bufferSz;
- if (!io_multiplexing_in || fd != multiplex_in_fd)
+ if (fd != multiplex_in_fd)
return read_timeout(fd, buf, len);
+ if (!io_multiplexing_in && remaining == 0) {
+ if (!buffer) {
+ bufferSz = 2 * IO_BUFFER_SIZE;
+ buffer = new_array(char, bufferSz);
+ if (!buffer)
+ out_of_memory("readfd_unbuffered");
+ }
+ remaining = read_timeout(fd, buffer, bufferSz);
+ bufferIdx = 0;
+ }
+
while (ret == 0) {
if (remaining) {
len = MIN(len, remaining);
- read_loop(fd, buf, len);
+ memcpy(buf, buffer + bufferIdx, len);
+ bufferIdx += len;
remaining -= len;
ret = len;
- continue;
+ break;
}
- read_loop(fd, ibuf, 4);
- tag = IVAL(ibuf, 0);
+ read_loop(fd, line, 4);
+ tag = IVAL(line, 0);
remaining = tag & 0xFFFFFF;
- tag = tag >> 24;
-
- if (tag == MPLEX_BASE) continue;
-
- tag -= MPLEX_BASE;
-
- if (tag != FERROR && tag != FINFO) {
- rprintf(FERROR,"unexpected tag %d\n", tag);
- exit_cleanup(1);
- }
-
- if (remaining > sizeof(line)-1) {
- rprintf(FERROR,"multiplexing overflow %d\n\n",
- remaining);
- exit_cleanup(1);
+ tag = (tag >> 24) - MPLEX_BASE;
+
+ switch (tag) {
+ case MSG_DATA:
+ if (!buffer || remaining > bufferSz) {
+ buffer = realloc_array(buffer, char, remaining);
+ if (!buffer)
+ out_of_memory("readfd_unbuffered");
+ bufferSz = remaining;
+ }
+ read_loop(fd, buffer, remaining);
+ bufferIdx = 0;
+ break;
+ case MSG_INFO:
+ case MSG_ERROR:
+ if (remaining >= sizeof line) {
+ rprintf(FERROR, "multiplexing overflow %d:%ld\n\n",
+ tag, (long)remaining);
+ exit_cleanup(RERR_STREAMIO);
+ }
+ read_loop(fd, line, remaining);
+ rwrite((enum logcode)tag, line, remaining);
+ remaining = 0;
+ break;
+ default:
+ rprintf(FERROR, "unexpected tag %d\n", tag);
+ exit_cleanup(RERR_STREAMIO);
}
-
- read_loop(fd, line, remaining);
- line[remaining] = 0;
-
- rprintf(tag,"%s", line);
- remaining = 0;
}
+ if (remaining == 0)
+ io_flush(NORMAL_FLUSH);
+
return ret;
}
-/* This function was added to overcome a deadlock problem when using
- * ssh. It looks like we can't allow our receive queue to get full or
- * ssh will clag up. Uggh. */
-static void read_check(int f)
-{
- int n = 8192;
-
- if (f == -1) return;
-
- if (read_buffer_len == 0) {
- read_buffer_p = read_buffer;
- }
-
- if (n > MAX_READ_BUFFER/4)
- n = MAX_READ_BUFFER/4;
-
- if (read_buffer_p != read_buffer) {
- memmove(read_buffer,read_buffer_p,read_buffer_len);
- read_buffer_p = read_buffer;
- }
-
- if (n > (read_buffer_size - read_buffer_len)) {
- read_buffer_size += n;
- read_buffer = (char *)Realloc(read_buffer,read_buffer_size);
- if (!read_buffer) out_of_memory("read check");
- read_buffer_p = read_buffer;
- }
-
- n = read_unbuffered(f,read_buffer+read_buffer_len,n);
- read_buffer_len += n;
-}
-
-
-/* do a buffered read from fd. don't return until all N bytes
- have been read. If all N can't be read then exit with an error */
-static void readfd(int fd,char *buffer,int N)
+/**
+ * Do a buffered read from @p fd. Don't return until all @p n bytes
+ * have been read. If all @p n can't be read then exit with an
+ * error.
+ **/
+static void readfd(int fd, char *buffer, size_t N)
{
int ret;
- int total=0;
-
- if ((read_buffer_len < N) && (N < 1024)) {
- read_check(buffer_f_in);
- }
-
- while (total < N) {
- if (read_buffer_len > 0 && buffer_f_in == fd) {
- ret = MIN(read_buffer_len,N-total);
- memcpy(buffer+total,read_buffer_p,ret);
- read_buffer_p += ret;
- read_buffer_len -= ret;
- total += ret;
- continue;
- }
-
- no_flush_read++;
- io_flush();
- no_flush_read--;
+ size_t total = 0;
- ret = read_unbuffered(fd,buffer + total,N-total);
+ while (total < N) {
+ ret = readfd_unbuffered(fd, buffer + total, N-total);
total += ret;
}
+
+ stats.total_read += total;
}
int32 read_int(int f)
{
char b[4];
+ int32 ret;
+
readfd(f,b,4);
- return IVAL(b,0);
+ ret = IVAL(b,0);
+ if (ret == (int32)0xffffffff)
+ return -1;
+ return ret;
}
int64 read_longint(int f)
{
- extern int remote_version;
int64 ret;
char b[8];
ret = read_int(f);
- if ((int32)ret != (int32)0xffffffff) return ret;
+ if ((int32)ret != (int32)0xffffffff)
+ return ret;
#ifdef NO_INT64
rprintf(FERROR,"Integer overflow - attempted 64 bit offset\n");
- exit_cleanup(1);
+ exit_cleanup(RERR_UNSUPPORTED);
#else
- if (remote_version >= 16) {
- readfd(f,b,8);
- ret = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
- }
+ readfd(f,b,8);
+ ret = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
#endif
return ret;
}
-void read_buf(int f,char *buf,int len)
+void read_buf(int f,char *buf,size_t len)
{
readfd(f,buf,len);
}
-void read_sbuf(int f,char *buf,int len)
+void read_sbuf(int f,char *buf,size_t len)
{
read_buf(f,buf,len);
buf[len] = 0;
unsigned char read_byte(int f)
{
unsigned char c;
- read_buf(f,(char *)&c,1);
+ read_buf(f, (char *)&c, 1);
return c;
}
+/**
+ * Sleep after writing to limit I/O bandwidth usage.
+ *
+ * @todo Rather than sleeping after each write, it might be better to
+ * use some kind of averaging. The current algorithm seems to always
+ * use a bit less bandwidth than specified, because it doesn't make up
+ * for slow periods. But arguably this is a feature. In addition, we
+ * ought to take the time used to write the data into account.
+ *
+ * During some phases of big transfers (file FOO is uptodate) this is
+ * called with a small bytes_written every time. As the kernel has to
+ * round small waits up to guarantee that we actually wait at least the
+ * requested number of microseconds, this can become grossly inaccurate.
+ * We therefore keep track of the bytes we've written over time and only
+ * sleep when the accumulated delay is at least 1 tenth of a second.
+ **/
+static void sleep_for_bwlimit(int bytes_written)
+{
+ static struct timeval prior_tv;
+ static long total_written = 0;
+ struct timeval tv, start_tv;
+ long elapsed_usec, sleep_usec;
+
+#define ONE_SEC 1000000L /* # of microseconds in a second */
+
+ if (!bwlimit)
+ return;
+
+ total_written += bytes_written;
+
+ gettimeofday(&start_tv, NULL);
+ if (prior_tv.tv_sec) {
+ elapsed_usec = (start_tv.tv_sec - prior_tv.tv_sec) * ONE_SEC
+ + (start_tv.tv_usec - prior_tv.tv_usec);
+ total_written -= elapsed_usec * bwlimit / (ONE_SEC/1024);
+ if (total_written < 0)
+ total_written = 0;
+ }
+
+ sleep_usec = total_written * (ONE_SEC/1024) / bwlimit;
+ if (sleep_usec < ONE_SEC / 10) {
+ prior_tv = start_tv;
+ return;
+ }
+
+ tv.tv_sec = sleep_usec / ONE_SEC;
+ tv.tv_usec = sleep_usec % ONE_SEC;
+ select(0, NULL, NULL, NULL, &tv);
+
+ gettimeofday(&prior_tv, NULL);
+ elapsed_usec = (prior_tv.tv_sec - start_tv.tv_sec) * ONE_SEC
+ + (prior_tv.tv_usec - start_tv.tv_usec);
+ total_written = (sleep_usec - elapsed_usec) * bwlimit / (ONE_SEC/1024);
+}
+
-/* write len bytes to fd, possibly reading from buffer_f_in if set
- in order to unclog the pipe. don't return until all len
- bytes have been written */
-static void writefd_unbuffered(int fd,char *buf,int len)
+/**
+ * Write len bytes to the file descriptor @p fd.
+ *
+ * This function underlies the multiplexing system. The body of the
+ * application never calls this function directly.
+ **/
+static void writefd_unbuffered(int fd,char *buf,size_t len)
{
- int total = 0;
+ size_t n, total = 0;
fd_set w_fds, r_fds;
- int fd_count, count;
+ int maxfd, count, ret;
struct timeval tv;
- int reading=0;
- int blocked=0;
+
+ if (fd == msg_fd_out) {
+ rprintf(FERROR, "Internal error: wrong write used in receiver.\n");
+ exit_cleanup(RERR_PROTOCOL);
+ }
no_flush++;
while (total < len) {
FD_ZERO(&w_fds);
- FD_ZERO(&r_fds);
FD_SET(fd,&w_fds);
- fd_count = fd+1;
+ maxfd = fd;
- if (!no_flush_read) {
- reading = (buffer_f_in != -1);
+ if (msg_fd_in >= 0) {
+ FD_ZERO(&r_fds);
+ FD_SET(msg_fd_in,&r_fds);
+ if (msg_fd_in > maxfd)
+ maxfd = msg_fd_in;
}
- if (reading) {
- FD_SET(buffer_f_in,&r_fds);
- if (buffer_f_in > fd)
- fd_count = buffer_f_in+1;
- }
-
- tv.tv_sec = io_timeout?io_timeout:SELECT_TIMEOUT;
+ tv.tv_sec = select_timeout;
tv.tv_usec = 0;
- count = select(fd_count,
- reading?&r_fds:NULL,
- &w_fds,NULL,
- &tv);
+ errno = 0;
+ count = select(maxfd + 1, msg_fd_in >= 0 ? &r_fds : NULL,
+ &w_fds, NULL, &tv);
if (count <= 0) {
+ if (count < 0 && errno == EBADF)
+ exit_cleanup(RERR_SOCKETIO);
check_timeout();
continue;
}
- if (reading && FD_ISSET(buffer_f_in, &r_fds)) {
- read_check(buffer_f_in);
- }
+ if (msg_fd_in >= 0 && FD_ISSET(msg_fd_in, &r_fds))
+ read_msg_fd();
- if (FD_ISSET(fd, &w_fds)) {
- int n = (len-total)>>blocked;
- int ret = write(fd,buf+total,n?n:1);
+ if (!FD_ISSET(fd, &w_fds))
+ continue;
- if (ret == -1 && errno == EINTR) {
- continue;
+ n = len - total;
+ if (bwlimit && n > bwlimit_writemax)
+ n = bwlimit_writemax;
+ ret = write(fd, buf + total, n);
+
+ if (ret <= 0) {
+ if (ret < 0) {
+ if (errno == EINTR)
+ continue;
+ if (errno == EWOULDBLOCK || errno == EAGAIN) {
+ msleep(1);
+ continue;
+ }
}
- if (ret == -1 &&
- (errno == EAGAIN || errno == EWOULDBLOCK)) {
- blocked++;
- continue;
- }
+ /* Don't try to write errors back across the stream. */
+ io_multiplexing_close();
+ rsyserr(FERROR, errno,
+ "writefd_unbuffered failed to write %ld bytes: phase \"%s\"",
+ (long)len, io_write_phase);
+ exit_cleanup(RERR_STREAMIO);
+ }
- if (ret <= 0) {
- rprintf(FERROR,"erroring writing %d bytes - exiting\n", len);
- exit_cleanup(1);
- }
+ sleep_for_bwlimit(ret);
- blocked = 0;
- total += ret;
- stats.total_written += ret;
+ total += ret;
- if (io_timeout)
- last_io = time(NULL);
- }
+ if (io_timeout)
+ last_io = time(NULL);
}
no_flush--;
static char *io_buffer;
static int io_buffer_count;
-void io_start_buffering(int fd)
+void io_start_buffering_out(int fd)
{
- if (io_buffer) return;
+ if (io_buffer)
+ return;
multiplex_out_fd = fd;
- io_buffer = (char *)malloc(IO_BUFFER_SIZE+4);
- if (!io_buffer) out_of_memory("writefd");
+ io_buffer = new_array(char, IO_BUFFER_SIZE);
+ if (!io_buffer)
+ out_of_memory("writefd");
io_buffer_count = 0;
+}
- /* leave room for the multiplex header in case it's needed */
- io_buffer += 4;
+void io_start_buffering_in(int fd)
+{
+ multiplex_in_fd = fd;
}
-void io_flush(void)
+/**
+ * Write an message to a multiplexed stream. If this fails then rsync
+ * exits.
+ **/
+static void mplex_write(int fd, enum msgcode code, char *buf, size_t len)
+{
+ char buffer[4096];
+ size_t n = len;
+
+ SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len);
+
+ if (n > sizeof buffer - 4)
+ n = sizeof buffer - 4;
+
+ memcpy(&buffer[4], buf, n);
+ writefd_unbuffered(fd, buffer, n+4);
+
+ len -= n;
+ buf += n;
+
+ if (len)
+ writefd_unbuffered(fd, buf, len);
+}
+
+
+void io_flush(int flush_it_all)
{
int fd = multiplex_out_fd;
- if (!io_buffer_count || no_flush) return;
- if (io_multiplexing_out) {
- SIVAL(io_buffer-4, 0, (MPLEX_BASE<<24) + io_buffer_count);
- writefd_unbuffered(fd, io_buffer-4, io_buffer_count+4);
- } else {
+ msg_list_push(flush_it_all);
+
+ if (!io_buffer_count || no_flush)
+ return;
+
+ if (io_multiplexing_out)
+ mplex_write(fd, MSG_DATA, io_buffer, io_buffer_count);
+ else
writefd_unbuffered(fd, io_buffer, io_buffer_count);
- }
io_buffer_count = 0;
}
-void io_end_buffering(int fd)
+
+void io_end_buffering(void)
{
- io_flush();
+ io_flush(NORMAL_FLUSH);
if (!io_multiplexing_out) {
- free(io_buffer-4);
+ free(io_buffer);
io_buffer = NULL;
}
}
-static void writefd(int fd,char *buf,int len)
+static void writefd(int fd,char *buf,size_t len)
{
- if (!io_buffer) {
+ stats.total_written += len;
+
+ if (fd == msg_fd_out) {
+ rprintf(FERROR, "Internal error: wrong write used in receiver.\n");
+ exit_cleanup(RERR_PROTOCOL);
+ }
+
+ if (!io_buffer || fd != multiplex_out_fd) {
writefd_unbuffered(fd, buf, len);
return;
}
while (len) {
- int n = MIN(len, IO_BUFFER_SIZE-io_buffer_count);
+ int n = MIN((int)len, IO_BUFFER_SIZE-io_buffer_count);
if (n > 0) {
memcpy(io_buffer+io_buffer_count, buf, n);
buf += n;
len -= n;
io_buffer_count += n;
}
-
- if (io_buffer_count == IO_BUFFER_SIZE) io_flush();
+
+ if (io_buffer_count == IO_BUFFER_SIZE)
+ io_flush(NORMAL_FLUSH);
}
}
writefd(f,b,4);
}
+
+void write_int_named(int f, int32 x, const char *phase)
+{
+ io_write_phase = phase;
+ write_int(f, x);
+ io_write_phase = phase_unknown;
+}
+
+
+/*
+ * Note: int64 may actually be a 32-bit type if ./configure couldn't find any
+ * 64-bit types on this platform.
+ */
void write_longint(int f, int64 x)
{
- extern int remote_version;
char b[8];
- if (remote_version < 16 || x <= 0x7FFFFFFF) {
+ if (x <= 0x7FFFFFFF) {
write_int(f, (int)x);
return;
}
- write_int(f, -1);
+#ifdef NO_INT64
+ rprintf(FERROR,"Integer overflow - attempted 64 bit offset\n");
+ exit_cleanup(RERR_UNSUPPORTED);
+#else
+ write_int(f, (int32)0xFFFFFFFF);
SIVAL(b,0,(x&0xFFFFFFFF));
SIVAL(b,4,((x>>32)&0xFFFFFFFF));
writefd(f,b,8);
+#endif
}
-void write_buf(int f,char *buf,int len)
+void write_buf(int f,char *buf,size_t len)
{
writefd(f,buf,len);
}
-/* write a string to the connection */
+/** Write a string to the connection */
static void write_sbuf(int f,char *buf)
{
write_buf(f, buf, strlen(buf));
write_buf(f,(char *)&c,1);
}
-int read_line(int f, char *buf, int maxlen)
-{
- eof_error = 0;
+
+/**
+ * Read a line of up to @p maxlen characters into @p buf (not counting
+ * the trailing null). Strips the (required) trailing newline and all
+ * carriage returns.
+ *
+ * @return 1 for success; 0 for I/O error or truncation.
+ **/
+int read_line(int f, char *buf, size_t maxlen)
+{
while (maxlen) {
buf[0] = 0;
read_buf(f, buf, 1);
- if (buf[0] == 0) return 0;
- if (buf[0] == '\n') {
- buf[0] = 0;
+ if (buf[0] == 0)
+ return 0;
+ if (buf[0] == '\n')
break;
- }
if (buf[0] != '\r') {
buf++;
maxlen--;
}
}
- if (maxlen == 0) {
- *buf = 0;
- return 0;
- }
-
- eof_error = 1;
-
- return 1;
+ *buf = '\0';
+ return maxlen > 0;
}
void io_printf(int fd, const char *format, ...)
{
- va_list ap;
+ va_list ap;
char buf[1024];
int len;
-
+
va_start(ap, format);
- len = vslprintf(buf, sizeof(buf)-1, format, ap);
+ len = vsnprintf(buf, sizeof buf, format, ap);
va_end(ap);
- if (len < 0) exit_cleanup(1);
+ if (len < 0)
+ exit_cleanup(RERR_STREAMIO);
write_sbuf(fd, buf);
}
-/* setup for multiplexing an error stream with the data stream */
+/** Setup for multiplexing a MSG_* stream with the data stream. */
void io_start_multiplex_out(int fd)
{
multiplex_out_fd = fd;
- io_flush();
- io_start_buffering(fd);
+ io_flush(NORMAL_FLUSH);
+ io_start_buffering_out(fd);
io_multiplexing_out = 1;
}
-/* setup for multiplexing an error stream with the data stream */
+/** Setup for multiplexing a MSG_* stream with the data stream. */
void io_start_multiplex_in(int fd)
{
multiplex_in_fd = fd;
- io_flush();
- if (read_buffer_len) {
- fprintf(stderr,"ERROR: data in read buffer at mplx start\n");
- exit_cleanup(1);
- }
-
+ io_flush(NORMAL_FLUSH);
io_multiplexing_in = 1;
}
-/* write an message to the error stream */
-int io_multiplex_write(int f, char *buf, int len)
+/** Write an message to the multiplexed data stream. */
+int io_multiplex_write(enum msgcode code, char *buf, size_t len)
{
- if (!io_multiplexing_out) return 0;
-
- io_flush();
-
- SIVAL(io_buffer-4, 0, ((MPLEX_BASE + f)<<24) + len);
- memcpy(io_buffer, buf, len);
+ if (!io_multiplexing_out)
+ return 0;
- writefd_unbuffered(multiplex_out_fd, io_buffer-4, len+4);
+ io_flush(NORMAL_FLUSH);
+ stats.total_written += (len+4);
+ mplex_write(multiplex_out_fd, code, buf, len);
return 1;
}
-void io_close_input(int fd)
+/** Stop output multiplexing. */
+void io_multiplexing_close(void)
{
- buffer_f_in = -1;
+ io_multiplexing_out = 0;
}
+
git.samba.org / rsync.git / blobdiff