X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/0b4af330ced1003dcac7d169d0012ecf5c79e29f..787568f3719e0f80881fdf2124e11dc97c827ec4:/main.c diff --git a/main.c b/main.c index be8d0c2a..53a237ca 100644 --- a/main.c +++ b/main.c @@ -23,10 +23,19 @@ time_t starttime = 0; -struct stats stats; - +extern struct stats stats; extern int verbose; +/* there's probably never more than at most 2 outstanding child processes, + * but set it higher just in case. + */ +#define MAXCHILDPROCS 5 + +struct pid_status { + pid_t pid; + int status; +} pid_stat_table[MAXCHILDPROCS]; + static void show_malloc_stats(void); /**************************************************************************** @@ -34,11 +43,27 @@ wait for a process to exit, calling io_flush while waiting ****************************************************************************/ void wait_process(pid_t pid, int *status) { - while (waitpid(pid, status, WNOHANG) == 0) { + pid_t waited_pid; + int cnt; + + while ((waited_pid = waitpid(pid, status, WNOHANG)) == 0) { msleep(20); io_flush(); } + if ((waited_pid == -1) && (errno == ECHILD)) { + /* status of requested child no longer available. + * check to see if it was processed by the sigchld_handler. + */ + for (cnt = 0; cnt < MAXCHILDPROCS; cnt++) { + if (pid == pid_stat_table[cnt].pid) { + *status = pid_stat_table[cnt].status; + pid_stat_table[cnt].pid = 0; + break; + } + } + } + /* TODO: If the child exited on a signal, then log an * appropriate error message. Perhaps we should also accept a * message describing the purpose of the child. Also indicate @@ -172,9 +197,11 @@ static pid_t do_cmd(char *cmd,char *machine,char *user,char *path,int *f_in,int int i,argc=0; pid_t ret; char *tok,*dir=NULL; + int dash_l_set = 0; extern int local_server; extern char *rsync_path; extern int blocking_io; + extern int daemon_over_rsh; extern int read_batch; if (!read_batch && !local_server) { @@ -190,15 +217,22 @@ static pid_t do_cmd(char *cmd,char *machine,char *user,char *path,int *f_in,int args[argc++] = tok; } + /* check to see if we've already been given '-l user' in + the remote-shell command */ + for (i = 0; i < argc-1; i++) { + if (!strcmp(args[i], "-l") && args[i+1][0] != '-') + dash_l_set = 1; + } + #if HAVE_REMSH /* remsh (on HPUX) takes the arguments the other way around */ args[argc++] = machine; - if (user) { + if (user && !(daemon_over_rsh && dash_l_set)) { args[argc++] = "-l"; args[argc++] = user; } #else - if (user) { + if (user && !(daemon_over_rsh && dash_l_set)) { args[argc++] = "-l"; args[argc++] = user; } @@ -216,7 +250,7 @@ static pid_t do_cmd(char *cmd,char *machine,char *user,char *path,int *f_in,int args[argc++] = "."; - if (path && *path) + if (!daemon_over_rsh && path && *path) args[argc++] = path; args[argc] = NULL; @@ -231,7 +265,7 @@ static pid_t do_cmd(char *cmd,char *machine,char *user,char *path,int *f_in,int if (local_server) { if (read_batch) create_flist_from_batch(); /* sets batch_flist */ - ret = local_child(argc, args, f_in, f_out); + ret = local_child(argc, args, f_in, f_out, child_main); } else { ret = piped_child(args,f_in,f_out); } @@ -427,6 +461,9 @@ static int do_recv(int f_in,int f_out,struct file_list *flist,char *local_name) } io_flush(); + io_set_error_fd(-1); + /* workaround for cygwin hangs; wait to make sure child is ready */ + msleep(100); kill(pid, SIGUSR2); wait_process(pid, &status); return status; @@ -493,6 +530,13 @@ static void do_server_recv(int f_in, int f_out, int argc,char *argv[]) } +int child_main(int argc, char *argv[]) +{ + start_server(STDIN_FILENO, STDOUT_FILENO, argc, argv); + return 0; +} + + void start_server(int f_in, int f_out, int argc, char *argv[]) { extern int cvs_exclude; @@ -640,14 +684,14 @@ static int copy_argv (char *argv[]) } -/* +/** * Start a client for either type of remote connection. Work out * whether the arguments request a remote shell or rsyncd connection, * and call the appropriate connection function, then run_client. * * Calls either start_socket_client (for sockets) or do_cmd and * client_run (for ssh). - */ + **/ static int start_client(int argc, char *argv[]) { char *p; @@ -661,16 +705,16 @@ static int start_client(int argc, char *argv[]) extern int am_sender; extern char *shell_cmd; extern int rsync_port; - extern int whole_file; - extern int write_batch; + extern int daemon_over_rsh; extern int read_batch; int rc; /* Don't clobber argv[] so that ps(1) can still show the right command line. */ - if ((rc = copy_argv (argv))) + if ((rc = copy_argv(argv))) return rc; + /* rsync:// always uses rsync server over direct socket connection */ if (strncasecmp(URL_PREFIX, argv[0], strlen(URL_PREFIX)) == 0) { char *host, *path; @@ -680,7 +724,7 @@ static int start_client(int argc, char *argv[]) *p = 0; path = p+1; } else { - path=""; + path = ""; } p = strchr(host,':'); if (p) { @@ -691,12 +735,17 @@ static int start_client(int argc, char *argv[]) } if (!read_batch) { - p = find_colon(argv[0]); + p = find_colon(argv[0]); if (p) { - if (p[1] == ':') { + if (p[1] == ':') { /* double colon */ *p = 0; - return start_socket_client(argv[0], p+2, argc-1, argv+1); + if (!shell_cmd) { + return start_socket_client(argv[0], p+2, + argc-1, argv+1); + } + p++; + daemon_over_rsh = 1; } if (argc < 1) { @@ -713,18 +762,37 @@ static int start_client(int argc, char *argv[]) } else { am_sender = 1; + /* rsync:// destination uses rsync server over direct socket */ + if (strncasecmp(URL_PREFIX, argv[argc-1], strlen(URL_PREFIX)) == 0) { + char *host, *path; + + host = argv[argc-1] + strlen(URL_PREFIX); + p = strchr(host,'/'); + if (p) { + *p = 0; + path = p+1; + } else { + path = ""; + } + p = strchr(host,':'); + if (p) { + rsync_port = atoi(p+1); + *p = 0; + } + return start_socket_client(host, path, argc-1, argv); + } + p = find_colon(argv[argc-1]); if (!p) { local_server = 1; - /* - * disable "rsync algorithm" when both sides local, - * except when creating a batch update - */ - if (!write_batch && whole_file == -1) - whole_file = 1; - } else if (p[1] == ':') { + } else if (p[1] == ':') { /* double colon */ *p = 0; - return start_socket_client(argv[argc-1], p+2, argc-1, argv); + if (!shell_cmd) { + return start_socket_client(argv[argc-1], p+2, + argc-1, argv); + } + p++; + daemon_over_rsh = 1; } if (argc < 2) { @@ -775,8 +843,19 @@ static int start_client(int argc, char *argv[]) list_only = 1; } - pid = do_cmd(shell_cmd,shell_machine,shell_user,shell_path,&f_in,&f_out); - + pid = do_cmd(shell_cmd,shell_machine,shell_user,shell_path, + &f_in,&f_out); + + /* if we're running an rsync server on the remote host over a + remote shell command, we need to do the RSYNCD protocol first */ + if (daemon_over_rsh) { + int tmpret; + tmpret = start_inband_exchange(shell_user, shell_path, + f_in, f_out, argc); + if (tmpret < 0) + return tmpret; + } + ret = client_run(f_in, f_out, pid, argc, argv); fflush(stdout); @@ -786,22 +865,91 @@ static int start_client(int argc, char *argv[]) } -static RETSIGTYPE sigusr1_handler(int val) { +static RETSIGTYPE sigusr1_handler(int UNUSED(val)) { exit_cleanup(RERR_SIGNAL); } -static RETSIGTYPE sigusr2_handler(int val) { +static RETSIGTYPE sigusr2_handler(int UNUSED(val)) { extern int log_got_error; if (log_got_error) _exit(RERR_PARTIAL); _exit(0); } -static RETSIGTYPE sigchld_handler(int val) { +static RETSIGTYPE sigchld_handler(int UNUSED(val)) { #ifdef WNOHANG - while (waitpid(-1, NULL, WNOHANG) > 0) ; + int cnt, status; + pid_t pid; + /* An empty waitpid() loop was put here by Tridge and we could never + * get him to explain why he put it in, so rather than taking it + * out we're instead saving the child exit statuses for later use. + * The waitpid() loop presumably eliminates all possibility of leaving + * zombie children, maybe that's why he did it. + */ + while ((pid = waitpid(-1, &status, WNOHANG)) > 0) { + /* save the child's exit status */ + for (cnt = 0; cnt < MAXCHILDPROCS; cnt++) { + if (pid_stat_table[cnt].pid == 0) { + pid_stat_table[cnt].pid = pid; + pid_stat_table[cnt].status = status; + break; + } + } + } #endif } + +/** + * This routine catches signals and tries to send them to gdb. + * + * Because it's called from inside a signal handler it ought not to + * use too many library routines. + * + * @todo Perhaps use "screen -X" instead/as well, to help people + * debugging without easy access to X. Perhaps use an environment + * variable, or just call a script? + * + * @todo The /proc/ magic probably only works on Linux (and + * Solaris?) Can we be more portable? + **/ +#ifdef MAINTAINER_MODE +const char *get_panic_action(void) +{ + const char *cmd_fmt = getenv("RSYNC_PANIC_ACTION"); + + if (cmd_fmt) + return cmd_fmt; + else + return "xterm -display :0 -T Panic -n Panic " + "-e gdb /proc/%d/exe %d"; +} + + +/** + * Handle a fatal signal by launching a debugger, controlled by $RSYNC_PANIC_ACTION. + * + * This signal handler is only installed if we were configured with + * --enable-maintainer-mode. Perhaps it should always be on and we + * should just look at the environment variable, but I'm a bit leery + * of a signal sending us into a busy loop. + **/ +static RETSIGTYPE rsync_panic_handler(int UNUSED(whatsig)) +{ + char cmd_buf[300]; + int ret; + + sprintf(cmd_buf, get_panic_action(), + getpid(), getpid()); + + /* Unless we failed to execute gdb, we allow the process to + * continue. I'm not sure if that's right. */ + ret = system(cmd_buf); + if (ret) + _exit(ret); +} +#endif + + int main(int argc,char *argv[]) { extern int am_root; @@ -820,6 +968,12 @@ int main(int argc,char *argv[]) signal(SIGUSR1, sigusr1_handler); signal(SIGUSR2, sigusr2_handler); signal(SIGCHLD, sigchld_handler); +#ifdef MAINTAINER_MODE + signal(SIGSEGV, rsync_panic_handler); + signal(SIGFPE, rsync_panic_handler); + signal(SIGABRT, rsync_panic_handler); + signal(SIGBUS, rsync_panic_handler); +#endif /* def MAINTAINER_MODE */ starttime = time(NULL); am_root = (getuid() == 0); @@ -860,9 +1014,8 @@ int main(int argc,char *argv[]) write_batch_argvs_file(orig_argc, orig_argv); } - if (am_daemon) { + if (am_daemon && !am_server) return daemon_main(); - } if (argc < 1) { usage(FERROR); @@ -882,13 +1035,17 @@ int main(int argc,char *argv[]) if (am_server) { set_nonblocking(STDIN_FILENO); set_nonblocking(STDOUT_FILENO); + if (am_daemon) + return start_daemon(STDIN_FILENO, STDOUT_FILENO); start_server(STDIN_FILENO, STDOUT_FILENO, argc, argv); } ret = start_client(argc, argv); if (ret == -1) - exit_cleanup(RERR_STARTCLIENT); + exit_cleanup(RERR_STARTCLIENT); else - exit_cleanup(ret); - return ret; + exit_cleanup(ret); + + exit(ret); + /* NOTREACHED */ }