From d17e1dd2dae6bfd9e2e147a0dd3039848dd43abc Mon Sep 17 00:00:00 2001 From: Wayne Davison Date: Thu, 15 Jan 2004 07:42:17 +0000 Subject: [PATCH] - Moved the err_list* stuff here from log.c and renamed them msg_list*. - Renamed log_error_fd to msg_fd_out, and io_error_fd to msg_fd_in. - Added a redo_list* to keep track of any redo items that come over the message channel from the receiver to the generator. - The io_flush() and msg_list_push() functions now take an arg: NORMAL_FLUSH or FULL_FLUSH. The latter ensures that we don't lose any log messages that haven't gotten written from the msg_list. - Added a send_msg() function that log.c calls to send any remote log messages. It is also called to send the new MSG_REDO and MSG_DONE messages. --- io.c | 316 +++++++++++++++++++++++++++++++++++++++++++---------------- 1 file changed, 230 insertions(+), 86 deletions(-) diff --git a/io.c b/io.c index bf7f3d90..7bb3b088 100644 --- a/io.c +++ b/io.c @@ -49,6 +49,9 @@ static int no_flush; extern int bwlimit; extern int verbose; extern int io_timeout; +extern int am_server; +extern int am_daemon; +extern int am_sender; extern struct stats stats; @@ -74,8 +77,9 @@ const char *io_read_phase = phase_unknown; version is 24 or less. */ int kludge_around_eof = False; +int msg_fd_in = -1; +int msg_fd_out = -1; -static int io_error_fd = -1; static int io_filesfrom_f_in = -1; static int io_filesfrom_f_out = -1; static char io_filesfrom_buf[2048]; @@ -85,14 +89,44 @@ 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; + +static void redo_list_add(int num) +{ + 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) { - extern int am_server, am_daemon; time_t t; - err_list_push(); - - if (!io_timeout) return; + if (!io_timeout) + return; if (!last_io) { last_io = time(NULL); @@ -110,41 +144,155 @@ static void check_timeout(void) } } -/** Setup the fd used to propagate errors */ -void io_set_error_fd(int fd) +/** Setup the fd used to receive MSG_* messages. Only needed when + * we're the generator because the sender and receiver both use the + * multiplexed IO setup. */ +void set_msg_fd_in(int fd) +{ + msg_fd_in = fd; +} + +/** 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 IO 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) { - io_error_fd = fd; + 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; } -/** Read some data from the error fd and write it to the write log code */ -static void read_error_fd(void) +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[200]; size_t n; - int fd = io_error_fd; + int fd = msg_fd_in; int tag, len; - /* io_error_fd is temporarily disabled -- is this meant to - * prevent indefinite recursion? */ - io_error_fd = -1; + /* Temporarily disable msg_fd_in. This is needed because we + * may call a write routine that could try to call us back. */ + msg_fd_in = -1; read_loop(fd, buf, 4); tag = IVAL(buf, 0); len = tag & 0xFFFFFF; - tag = tag >> 24; - tag -= MPLEX_BASE; + tag = (tag >> 24) - MPLEX_BASE; - while (len) { - n = len; - if (n > (sizeof buf - 1)) - n = sizeof buf - 1; - read_loop(fd, buf, n); - rwrite((enum logcode)tag, buf, n); - len -= n; + switch (tag) { + case MSG_DONE: + if (len != 0) + exit_cleanup(RERR_STREAMIO); + redo_list_add(-1); + break; + case MSG_REDO: + if (len != 4) + 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: + exit_cleanup(RERR_STREAMIO); + } + + 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 called by 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 = io_timeout ? io_timeout : 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) +{ + struct redo_list *next; + int num; + + while (!redo_list_head) + read_msg_fd(); - io_error_fd = fd; + 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; } /** @@ -217,7 +365,7 @@ static int read_timeout(int fd, char *buf, size_t len) { int n, ret=0; - io_flush(); + io_flush(NORMAL_FLUSH); while (ret == 0) { /* until we manage to read *something* */ @@ -228,9 +376,10 @@ static int read_timeout(int fd, char *buf, size_t len) FD_ZERO(&r_fds); FD_SET(fd, &r_fds); - if (io_error_fd >= 0) { - FD_SET(io_error_fd, &r_fds); - if (io_error_fd >= fd_count) fd_count = io_error_fd+1; + if (msg_fd_in >= 0) { + FD_SET(msg_fd_in, &r_fds); + if (msg_fd_in >= fd_count) + fd_count = msg_fd_in+1; } if (io_filesfrom_f_out >= 0) { int new_fd; @@ -247,7 +396,8 @@ static int read_timeout(int fd, char *buf, size_t len) FD_SET(io_filesfrom_f_out, &w_fds); new_fd = io_filesfrom_f_out; } - if (new_fd >= fd_count) fd_count = new_fd+1; + if (new_fd >= fd_count) + fd_count = new_fd+1; } tv.tv_sec = io_timeout?io_timeout:SELECT_TIMEOUT; @@ -260,6 +410,7 @@ static int read_timeout(int fd, char *buf, size_t len) NULL, &tv); if (count == 0) { + msg_list_push(NORMAL_FLUSH); check_timeout(); } @@ -270,9 +421,8 @@ static int read_timeout(int fd, char *buf, size_t len) continue; } - if (io_error_fd >= 0 && FD_ISSET(io_error_fd, &r_fds)) { - read_error_fd(); - } + if (msg_fd_in >= 0 && FD_ISSET(msg_fd_in, &r_fds)) + read_msg_fd(); if (io_filesfrom_f_out >= 0) { if (io_filesfrom_buflen) { @@ -471,9 +621,10 @@ static int read_unbuffered(int fd, char *buf, size_t len) tag = IVAL(line, 0); remaining = tag & 0xFFFFFF; - tag = tag >> 24; + tag = (tag >> 24) - MPLEX_BASE; - if (tag == MPLEX_BASE) { + switch (tag) { + case MSG_DATA: if (!buffer || remaining > bufferSz) { buffer = realloc_array(buffer, char, remaining); if (!buffer) out_of_memory("read_unbuffered"); @@ -481,31 +632,26 @@ static int read_unbuffered(int fd, char *buf, size_t len) } read_loop(fd, buffer, remaining); bufferIdx = 0; - continue; - } - - tag -= MPLEX_BASE; - - if (tag != FERROR && tag != FINFO) { + 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); } - - if (remaining > sizeof line - 1) { - rprintf(FERROR, "multiplexing overflow %ld\n\n", - (long)remaining); - exit_cleanup(RERR_STREAMIO); - } - - read_loop(fd, line, remaining); - line[remaining] = 0; - - rprintf((enum logcode) tag, "%s", line); - remaining = 0; } if (remaining == 0) - io_flush(); + io_flush(NORMAL_FLUSH); return ret; } @@ -622,7 +768,7 @@ static void writefd_unbuffered(int fd,char *buf,size_t len) int fd_count, count; struct timeval tv; - err_list_push(); + msg_list_push(NORMAL_FLUSH); no_flush++; @@ -631,24 +777,22 @@ static void writefd_unbuffered(int fd,char *buf,size_t len) FD_SET(fd,&w_fds); fd_count = fd; - if (io_error_fd >= 0) { + if (msg_fd_in >= 0) { FD_ZERO(&r_fds); - FD_SET(io_error_fd,&r_fds); - if (io_error_fd > fd_count) - fd_count = io_error_fd; + FD_SET(msg_fd_in,&r_fds); + if (msg_fd_in > fd_count) + fd_count = msg_fd_in; } tv.tv_sec = io_timeout?io_timeout:SELECT_TIMEOUT; tv.tv_usec = 0; errno = 0; - - count = select(fd_count+1, - io_error_fd >= 0?&r_fds:NULL, - &w_fds,NULL, - &tv); + count = select(fd_count+1, msg_fd_in >= 0 ? &r_fds : NULL, + &w_fds, NULL, &tv); if (count == 0) { + msg_list_push(NORMAL_FLUSH); check_timeout(); } @@ -659,9 +803,8 @@ static void writefd_unbuffered(int fd,char *buf,size_t len) continue; } - if (io_error_fd >= 0 && FD_ISSET(io_error_fd, &r_fds)) { - read_error_fd(); - } + if (msg_fd_in >= 0 && FD_ISSET(msg_fd_in, &r_fds)) + read_msg_fd(); if (FD_ISSET(fd, &w_fds)) { int ret; @@ -722,7 +865,7 @@ void io_start_buffering_in(int fd) * Write an message to a multiplexed stream. If this fails then rsync * exits. **/ -static void mplex_write(int fd, enum logcode code, char *buf, size_t len) +static void mplex_write(int fd, enum msgcode code, char *buf, size_t len) { char buffer[4096]; size_t n = len; @@ -745,26 +888,26 @@ static void mplex_write(int fd, enum logcode code, char *buf, size_t len) } -void io_flush(void) +void io_flush(int flush_it_all) { int fd = multiplex_out_fd; + + msg_list_push(flush_it_all); - err_list_push(); - - if (!io_buffer_count || no_flush) return; + if (!io_buffer_count || no_flush) + return; - if (io_multiplexing_out) { - mplex_write(fd, FNONE, io_buffer, io_buffer_count); - } else { + 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(void) { - io_flush(); + io_flush(NORMAL_FLUSH); if (!io_multiplexing_out) { free(io_buffer); io_buffer = NULL; @@ -775,7 +918,7 @@ static void writefd(int fd,char *buf,size_t len) { stats.total_written += len; - err_list_push(); + msg_list_push(NORMAL_FLUSH); if (!io_buffer || fd != multiplex_out_fd) { writefd_unbuffered(fd, buf, len); @@ -791,7 +934,8 @@ static void writefd(int fd,char *buf,size_t len) io_buffer_count += n; } - if (io_buffer_count == IO_BUFFER_SIZE) io_flush(); + if (io_buffer_count == IO_BUFFER_SIZE) + io_flush(NORMAL_FLUSH); } } @@ -903,35 +1047,35 @@ void io_printf(int fd, const char *format, ...) } -/** 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_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(); + io_flush(NORMAL_FLUSH); io_multiplexing_in = 1; } -/** Write an message to the multiplexed error stream */ -int io_multiplex_write(enum logcode code, char *buf, size_t 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(); + io_flush(NORMAL_FLUSH); stats.total_written += (len+4); mplex_write(multiplex_out_fd, code, buf, len); return 1; } -/** Stop output multiplexing */ +/** Stop output multiplexing. */ void io_multiplexing_close(void) { io_multiplexing_out = 0; -- 2.34.1