X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/6d952fdbe7145d8ad0e4bec14181803db242673f..ef7441669b194ba6804c2eda07beed90a29ad2b3:/io.c diff --git a/io.c b/io.c index d0ddaf53..bf39ff91 100644 --- a/io.c +++ b/io.c @@ -38,8 +38,8 @@ extern int bwlimit; extern size_t bwlimit_writemax; extern int io_timeout; extern int am_server; -extern int am_daemon; extern int am_sender; +extern int am_receiver; extern int am_generator; extern int msgs2stderr; extern int inc_recurse; @@ -50,6 +50,7 @@ extern int file_total; extern int file_old_total; extern int list_only; extern int read_batch; +extern int compat_flags; extern int protect_args; extern int checksum_seed; extern int protocol_version; @@ -65,7 +66,6 @@ extern iconv_t ic_send, ic_recv; int csum_length = SHORT_SUM_LENGTH; /* initial value */ int allowed_lull = 0; -int ignore_timeout = 0; int batch_fd = -1; int msgdone_cnt = 0; int forward_flist_data = 0; @@ -84,7 +84,7 @@ static struct { xbuf in, out, msg; int in_fd; int out_fd; /* Both "out" and "msg" go to this fd. */ - BOOL in_multiplexed; + int in_multiplexed; unsigned out_empty_len; size_t raw_data_header_pos; /* in the out xbuf */ size_t raw_flushing_ends_before; /* in the out xbuf */ @@ -127,7 +127,8 @@ static char int_byte_extra[64] = { #define IOBUF_WAS_REDUCED(siz) ((siz) & 0xFF) #define IOBUF_RESTORE_SIZE(siz) (((siz) | 0xFF) + 1) -#define IN_MULTIPLEXED (iobuf.in_multiplexed) +#define IN_MULTIPLEXED (iobuf.in_multiplexed != 0) +#define IN_MULTIPLEXED_AND_READY (iobuf.in_multiplexed > 0) #define OUT_MULTIPLEXED (iobuf.out_empty_len != 0) #define PIO_NEED_INPUT (1<<0) /* The *_NEED_* flags are mutually exclusive. */ @@ -152,25 +153,43 @@ static void read_a_msg(void); static void drain_multiplex_messages(void); static void sleep_for_bwlimit(int bytes_written); -static void check_timeout(void) -{ - time_t t; - - if (!io_timeout || ignore_timeout) +static void check_timeout(BOOL allow_keepalive) +{ + time_t t, chk; + + /* On the receiving side, the generator is now the one that decides + * when a timeout has occurred. When it is sifting through a lot of + * files looking for work, it will be sending keep-alive messages to + * the sender, and even though the receiver won't be sending/receiving + * anything (not even keep-alive messages), the successful writes to + * the sender will keep things going. If the receiver is actively + * receiving data, it will ensure that the generator knows that it is + * not idle by sending the generator keep-alive messages (since the + * generator might be blocked trying to send checksums, it needs to + * know that the receiver is active). Thus, as long as one or the + * other is successfully doing work, the generator will not timeout. */ + if (!io_timeout) return; - if (!last_io_in) { - last_io_in = time(NULL); - return; + t = time(NULL); + + if (allow_keepalive) { + /* This may put data into iobuf.msg w/o flushing. */ + maybe_send_keepalive(t, 0); } - t = time(NULL); + if (!last_io_in) + last_io_in = t; - if (t - last_io_in >= io_timeout) { - if (!am_server && !am_daemon) { - rprintf(FERROR, "io timeout after %d seconds -- exiting\n", - (int)(t-last_io_in)); - } + if (am_receiver) + return; + + chk = MAX(last_io_out, last_io_in); + if (t - chk >= io_timeout) { + if (am_server) + msgs2stderr = 1; + rprintf(FERROR, "[%s] io timeout after %d seconds -- exiting\n", + who_am_i(), (int)(t-chk)); exit_cleanup(RERR_TIMEOUT); } } @@ -252,7 +271,8 @@ static size_t safe_read(int fd, char *buf, size_t len) who_am_i()); exit_cleanup(RERR_FILEIO); } - check_timeout(); + if (io_timeout) + maybe_send_keepalive(time(NULL), MSK_ALLOW_FLUSH); continue; } @@ -336,7 +356,8 @@ static void safe_write(int fd, const char *buf, size_t len) what_fd_is(fd), who_am_i()); exit_cleanup(RERR_FILEIO); } - check_timeout(); + if (io_timeout) + maybe_send_keepalive(time(NULL), MSK_ALLOW_FLUSH); continue; } @@ -489,23 +510,25 @@ void restore_iobuf_size(xbuf *out) } } -/* Perform buffered input and output until specified conditions are met. When - * given a "needed" read requirement, we'll return without doing any I/O if the - * iobuf.in bytes are already available. When reading, we'll read as many - * bytes as we can into the buffer, and return as soon as we meet the minimum - * read requirement. When given a "needed" write requirement, we'll return - * without doing any I/O if that many bytes will fit in the output buffer (we - * check either iobuf.out or iobuf.msg, depending on the flags). When writing, - * we write out as much as we can, and return as soon as the given free-space - * requirement is available. +/* Perform buffered input and/or output until specified conditions are met. + * When given a "needed" read or write request, this returns without doing any + * I/O if the needed input bytes or write space is already available. Once I/O + * is needed, this will try to do whatever reading and/or writing is currently + * possible, up to the maximum buffer allowances, no matter if this is a read + * or write request. However, the I/O stops as soon as the required input + * bytes or output space is available. If this is not a read request, the + * routine may also do some advantageous reading of messages from a multiplexed + * input source (which ensures that we don't jam up with everyone in their + * "need to write" code and nobody reading the accumulated data that would make + * writing possible). * - * The iobuf.out and iobuf.msg buffers are circular, so some writes into them - * will need to be split when the data needs to wrap around to the start. In - * order to help make this easier for some operations (such as the use of - * SIVAL() into the buffer) a buffer may be temporarily shortened, but the - * original size will be automatically restored. The iobuf.in buffer is also - * circular, so callers may need to split their reading of the data if it spans - * the end. See also the 3 raw_* iobuf vars that are used in the handling of + * The iobuf.in, .out and .msg buffers are all circular. Callers need to be + * aware that some data copies will need to be split when the bytes wrap around + * from the end to the start. In order to help make writing into the output + * buffers easier for some operations (such as the use of SIVAL() into the + * buffer) a buffer may be temporarily shortened by a small amount, but the + * original size will be automatically restored when the .pos wraps to the + * start. See also the 3 raw_* iobuf vars that are used in the handling of * MSG_DATA bytes as they are read-from/written-into the buffers. * * When writing, we flush data in the following priority order: @@ -731,7 +754,7 @@ static char *perform_io(size_t needed, int flags) send_extra_file_list(sock_f_out, -1); extra_flist_sending_enabled = !flist_eof; } else - check_timeout(); + check_timeout((flags & PIO_NEED_INPUT) != 0); FD_ZERO(&r_fds); /* Just in case... */ FD_ZERO(&w_fds); } @@ -768,14 +791,17 @@ static char *perform_io(size_t needed, int flags) if (msgs2stderr && DEBUG_GTE(IO, 2)) rprintf(FINFO, "[%s] recv=%ld\n", who_am_i(), (long)n); - if (io_timeout) + if (io_timeout) { last_io_in = time(NULL); + if (flags & PIO_NEED_INPUT) + maybe_send_keepalive(last_io_in, 0); + } stats.total_read += n; iobuf.in.len += n; } - if (iobuf.out_fd >= 0 && FD_ISSET(iobuf.out_fd, &w_fds)) { + if (out && FD_ISSET(iobuf.out_fd, &w_fds)) { size_t len = iobuf.raw_flushing_ends_before ? iobuf.raw_flushing_ends_before - out->pos : out->len; int n; @@ -826,7 +852,7 @@ static char *perform_io(size_t needed, int flags) /* We need to help prevent deadlock by doing what reading * we can whenever we are here trying to write. */ - if (IN_MULTIPLEXED && !(flags & PIO_NEED_INPUT)) { + if (IN_MULTIPLEXED_AND_READY && !(flags & PIO_NEED_INPUT)) { while (!iobuf.raw_input_ends_before && iobuf.in.len > 512) read_a_msg(); if (flist_receiving_enabled && iobuf.in.len > 512) @@ -896,7 +922,7 @@ void noop_io_until_death(void) read_buf(iobuf.in_fd, buf, sizeof buf); } -/* Buffer a message for the multiplexed output stream. Is never used for MSG_DATA. */ +/* Buffer a message for the multiplexed output stream. Is not used for (normal) MSG_DATA. */ int send_msg(enum msgcode code, const char *buf, size_t len, int convert) { char *hdr; @@ -958,8 +984,8 @@ int send_msg(enum msgcode code, const char *buf, size_t len, int convert) { size_t siz; - if ((pos += 4) >= iobuf.msg.size) - pos -= iobuf.msg.size; + if ((pos += 4) == iobuf.msg.size) + pos = 0; /* Handle a split copy if we wrap around the end of the circular buffer. */ if (pos >= iobuf.msg.pos && (siz = iobuf.msg.size - pos) < len) { @@ -1040,13 +1066,15 @@ void io_set_sock_fds(int f_in, int f_out) void set_io_timeout(int secs) { io_timeout = secs; + allowed_lull = (io_timeout + 1) / 2; - if (!io_timeout || io_timeout > SELECT_TIMEOUT) + if (!io_timeout || allowed_lull > SELECT_TIMEOUT) select_timeout = SELECT_TIMEOUT; else - select_timeout = io_timeout; + select_timeout = allowed_lull; - allowed_lull = read_batch ? 0 : (io_timeout + 1) / 2; + if (read_batch) + allowed_lull = 0; } static void check_for_d_option_error(const char *msg) @@ -1313,20 +1341,29 @@ void maybe_flush_socket(int important) io_flush(NORMAL_FLUSH); } -void maybe_send_keepalive(void) +/* Older rsync versions used to send either a MSG_NOOP (protocol 30) or a + * raw-data-based keep-alive (protocol 29), both of which implied forwarding of + * the message through the sender. Since the new timeout method does not need + * any forwarding, we just send an empty MSG_DATA message, which works with all + * rsync versions. This avoids any message forwarding, and leaves the raw-data + * stream alone (since we can never be quite sure if that stream is in the + * right state for a keep-alive message). */ +void maybe_send_keepalive(time_t now, int flags) { - if (time(NULL) - last_io_out >= allowed_lull) { - if (!iobuf.msg.len && iobuf.out.len == iobuf.out_empty_len) { - if (protocol_version < 29) - return; /* there's nothing we can do */ - if (protocol_version >= 30) - send_msg(MSG_NOOP, "", 0, 0); - else { - write_int(iobuf.out_fd, cur_flist->used); - write_shortint(iobuf.out_fd, ITEM_IS_NEW); - } - } - if (iobuf.msg.len) + if (flags & MSK_ACTIVE_RECEIVER) + last_io_in = now; /* Fudge things when we're working hard on the files. */ + + if (now - last_io_out >= allowed_lull) { + /* The receiver is special: it only sends keep-alive messages if it is + * actively receiving data. Otherwise, it lets the generator timeout. */ + if (am_receiver && now - last_io_in >= io_timeout) + return; + + if (!iobuf.msg.len && iobuf.out.len == iobuf.out_empty_len) + send_msg(MSG_DATA, "", 0, 0); + if (!(flags & MSK_ALLOW_FLUSH)) { + /* Let the caller worry about writing out the data. */ + } else if (iobuf.msg.len) perform_io(iobuf.msg.size - iobuf.msg.len + 1, PIO_NEED_MSGROOM); else if (iobuf.out.len > iobuf.out_empty_len) io_flush(NORMAL_FLUSH); @@ -1351,12 +1388,18 @@ static void read_a_msg(void) int tag, val; size_t msg_bytes; + /* This ensures that perform_io() does not try to do any message reading + * until we've read all of the data for this message. We should also + * try to avoid calling things that will cause data to be written via + * perform_io() prior to this being reset to 1. */ + iobuf.in_multiplexed = -1; + tag = raw_read_int(); msg_bytes = tag & 0xFFFFFF; tag = (tag >> 24) - MPLEX_BASE; - if (DEBUG_GTE(IO, 1) && (msgs2stderr || tag != MSG_INFO)) + if (DEBUG_GTE(IO, 1) && msgs2stderr) rprintf(FINFO, "[%s] got msg=%d, len=%ld\n", who_am_i(), (int)tag, (long)msg_bytes); switch (tag) { @@ -1366,31 +1409,38 @@ static void read_a_msg(void) * the buffer the msg data will end once it is read. It is * possible that this points off the end of the buffer, in * which case the gradual reading of the input stream will - * cause this value to decrease and eventually become real. */ - iobuf.raw_input_ends_before = iobuf.in.pos + msg_bytes; + * cause this value to wrap around and eventually become real. */ + if (msg_bytes) + iobuf.raw_input_ends_before = iobuf.in.pos + msg_bytes; + iobuf.in_multiplexed = 1; break; case MSG_STATS: if (msg_bytes != sizeof stats.total_read || !am_generator) goto invalid_msg; raw_read_buf((char*)&stats.total_read, sizeof stats.total_read); + iobuf.in_multiplexed = 1; break; case MSG_REDO: if (msg_bytes != 4 || !am_generator) goto invalid_msg; - got_flist_entry_status(FES_REDO, raw_read_int()); + val = raw_read_int(); + iobuf.in_multiplexed = 1; + got_flist_entry_status(FES_REDO, val); break; case MSG_IO_ERROR: - if (msg_bytes != 4 || am_sender) + if (msg_bytes != 4) goto invalid_msg; val = raw_read_int(); + iobuf.in_multiplexed = 1; io_error |= val; - if (!am_generator) + if (am_receiver) send_msg_int(MSG_IO_ERROR, val); break; case MSG_IO_TIMEOUT: if (msg_bytes != 4 || am_server || am_generator) goto invalid_msg; val = raw_read_int(); + iobuf.in_multiplexed = 1; if (!io_timeout || io_timeout > val) { if (INFO_GTE(MISC, 2)) rprintf(FINFO, "Setting --timeout=%d to match server\n", val); @@ -1398,14 +1448,19 @@ static void read_a_msg(void) } break; case MSG_NOOP: + /* Support protocol-30 keep-alive method. */ + if (msg_bytes != 0) + goto invalid_msg; + iobuf.in_multiplexed = 1; if (am_sender) - maybe_send_keepalive(); + maybe_send_keepalive(time(NULL), MSK_ALLOW_FLUSH); break; case MSG_DELETED: if (msg_bytes >= sizeof data) goto overflow; if (am_generator) { raw_read_buf(data, msg_bytes); + iobuf.in_multiplexed = 1; send_msg(MSG_DELETED, data, msg_bytes, 1); break; } @@ -1444,6 +1499,7 @@ static void read_a_msg(void) } else #endif raw_read_buf(data, msg_bytes); + iobuf.in_multiplexed = 1; /* A directory name was sent with the trailing null */ if (msg_bytes > 0 && !data[msg_bytes-1]) log_delete(data, S_IFDIR); @@ -1461,6 +1517,7 @@ static void read_a_msg(void) exit_cleanup(RERR_STREAMIO); } val = raw_read_int(); + iobuf.in_multiplexed = 1; if (am_generator) got_flist_entry_status(FES_SUCCESS, val); else @@ -1470,6 +1527,7 @@ static void read_a_msg(void) if (msg_bytes != 4) goto invalid_msg; val = raw_read_int(); + iobuf.in_multiplexed = 1; if (am_generator) got_flist_entry_status(FES_NO_SEND, val); else @@ -1497,6 +1555,7 @@ static void read_a_msg(void) exit_cleanup(RERR_STREAMIO); } raw_read_buf(data, msg_bytes); + iobuf.in_multiplexed = 1; rwrite((enum logcode)tag, data, msg_bytes, !am_generator); if (first_message) { if (list_only && !am_sender && tag == 1 && msg_bytes < sizeof data) { @@ -1507,8 +1566,15 @@ static void read_a_msg(void) } break; case MSG_ERROR_EXIT: + if (msg_bytes == 4) + val = raw_read_int(); + else if (msg_bytes == 0) + val = 0; + else + goto invalid_msg; + iobuf.in_multiplexed = 1; if (DEBUG_GTE(EXIT, 3)) - rprintf(FINFO, "[%s] got MSG_ERROR_EXIT with %d bytes\n", who_am_i(), msg_bytes); + rprintf(FINFO, "[%s] got MSG_ERROR_EXIT with %ld bytes\n", who_am_i(), (long)msg_bytes); if (msg_bytes == 0) { if (!am_sender && !am_generator) { if (DEBUG_GTE(EXIT, 3)) { @@ -1518,26 +1584,21 @@ static void read_a_msg(void) send_msg(MSG_ERROR_EXIT, "", 0, 0); io_flush(FULL_FLUSH); } - val = 0; - } else if (msg_bytes == 4) { - val = raw_read_int(); - if (protocol_version >= 31) { - if (am_generator) { - if (DEBUG_GTE(EXIT, 3)) { - rprintf(FINFO, "[%s] sending MSG_ERROR_EXIT with exit_code %d\n", - who_am_i(), val); - } - send_msg_int(MSG_ERROR_EXIT, val); - } else { - if (DEBUG_GTE(EXIT, 3)) { - rprintf(FINFO, "[%s] sending MSG_ERROR_EXIT (len 0)\n", - who_am_i()); - } - send_msg(MSG_ERROR_EXIT, "", 0, 0); + } else if (protocol_version >= 31) { + if (am_generator) { + if (DEBUG_GTE(EXIT, 3)) { + rprintf(FINFO, "[%s] sending MSG_ERROR_EXIT with exit_code %d\n", + who_am_i(), val); + } + send_msg_int(MSG_ERROR_EXIT, val); + } else { + if (DEBUG_GTE(EXIT, 3)) { + rprintf(FINFO, "[%s] sending MSG_ERROR_EXIT (len 0)\n", + who_am_i()); } + send_msg(MSG_ERROR_EXIT, "", 0, 0); } - } else - goto invalid_msg; + } /* Send a negative linenum so that we don't end up * with a duplicate exit message. */ _exit_cleanup(val, __FILE__, 0 - __LINE__); @@ -1546,11 +1607,13 @@ static void read_a_msg(void) tag, who_am_i(), inc_recurse ? "/inc" : ""); exit_cleanup(RERR_STREAMIO); } + + assert(iobuf.in_multiplexed > 0); } static void drain_multiplex_messages(void) { - while (IN_MULTIPLEXED && iobuf.in.len) { + while (IN_MULTIPLEXED_AND_READY && iobuf.in.len) { if (iobuf.raw_input_ends_before) { size_t raw_len = iobuf.raw_input_ends_before - iobuf.in.pos; iobuf.raw_input_ends_before = 0; @@ -2207,7 +2270,7 @@ void io_start_multiplex_in(int fd) if (msgs2stderr && DEBUG_GTE(IO, 2)) rprintf(FINFO, "[%s] io_start_multiplex_in(%d)\n", who_am_i(), fd); - iobuf.in_multiplexed = True; /* See also IN_MULTIPLEXED */ + iobuf.in_multiplexed = 1; /* See also IN_MULTIPLEXED */ io_start_buffering_in(fd); } @@ -2218,7 +2281,7 @@ int io_end_multiplex_in(int mode) if (msgs2stderr && DEBUG_GTE(IO, 2)) rprintf(FINFO, "[%s] io_end_multiplex_in(mode=%d)\n", who_am_i(), mode); - iobuf.in_multiplexed = False; + iobuf.in_multiplexed = 0; if (mode == MPLX_SWITCHING) iobuf.raw_input_ends_before = 0; else @@ -2256,7 +2319,7 @@ void start_write_batch(int fd) * is involved. */ write_int(batch_fd, protocol_version); if (protocol_version >= 30) - write_byte(batch_fd, inc_recurse); + write_byte(batch_fd, compat_flags); write_int(batch_fd, checksum_seed); if (am_sender)