diff options
| -rw-r--r-- | coreutils/watch.c | 82 | ||||
| -rw-r--r-- | include/libbb.h | 2 | ||||
| -rw-r--r-- | libbb/xfuncs.c | 34 |
3 files changed, 57 insertions, 61 deletions
diff --git a/coreutils/watch.c b/coreutils/watch.c index 9e0c54c..b783d34 100644 --- a/coreutils/watch.c +++ b/coreutils/watch.c @@ -4,20 +4,7 @@ * * Copyright (C) 2001 by Michael Habermann <mhabermann@gmx.de> * - * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */ /* BB_AUDIT SUSv3 N/A */ @@ -41,23 +28,18 @@ int watch_main(int argc, char **argv) { - const int header_len = 40; - time_t t; - pid_t pid; + int width, len; unsigned period = 2; - int old_stdout; - int len, len2; - char **watched_argv; - char header[header_len + 1]; + char **watched_argv, *header; - if (argc < 2) { - bb_show_usage(); - } + if (argc < 2) bb_show_usage(); + + get_terminal_width_height(1, &width, 0); + header = xzalloc(width--); /* don't use getopt, because it permutes the arguments */ ++argv; - if ((argc > 3) && !strcmp(*argv, "-n") - ) { + if ((argc > 3) && !strcmp(*argv, "-n")) { period = bb_xgetularg10_bnd(argv[1], 1, UINT_MAX); argv += 2; } @@ -65,44 +47,22 @@ int watch_main(int argc, char **argv) /* create header */ - len = snprintf(header, header_len, "Every %ds:", period); - /* Don't bother checking for len < 0, as it should never happen. - * But, just to be prepared... */ - assert(len >= 0); - do { - len2 = strlen(*argv); - if (len + len2 >= header_len-1) { - break; - } - header[len] = ' '; - memcpy(header+len+1, *argv, len2); - len += len2+1; - } while (*++argv); - - header[len] = 0; - - /* thanks to lye, who showed me how to redirect stdin/stdout */ - old_stdout = dup(STDOUT_FILENO); + len = snprintf(header, width, "Every %ds:", period); + while (*argv && len<width) + snprintf(header+len, width-len, " %s", *(argv++)); while (1) { + char *thyme; + time_t t; + time(&t); - /* Use dprintf to avoid fflush()ing stdout. */ - if (dprintf(1, "\033[H\033[J%-*s%s\n", header_len, header, ctime(&t)) < 0) { - bb_perror_msg_and_die("printf"); - } + thyme = ctime(&t); + len = strlen(thyme); + if (len < width) header[width-len] = 0; + + printf("\033[H\033[J%s %s\n", header, thyme); - pid = vfork(); /* vfork, because of ucLinux */ - if (pid > 0) { - //parent - wait(0); - sleep(period); - } else if (0 == pid) { - //child - dup2(old_stdout, STDOUT_FILENO); - execvp(*watched_argv, watched_argv); - bb_perror_msg_and_die("%s", *watched_argv); - } else { - bb_perror_msg_and_die("vfork"); - } + waitpid(bb_xspawn(watched_argv),0,0); + sleep(period); } } diff --git a/include/libbb.h b/include/libbb.h index ca3afea..928e25d 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -146,6 +146,8 @@ extern void bb_fflush_stdout_and_exit(int retval) ATTRIBUTE_NORETURN; extern void xstat(const char *filename, struct stat *buf); extern int bb_xsocket(int domain, int type, int protocol); +extern pid_t bb_spawn(char **argv); +extern pid_t bb_xspawn(char **argv); extern void bb_xdaemon(int nochdir, int noclose); extern void bb_xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen); extern void bb_xlisten(int s, int backlog); diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c index d3c9e41..2cfafb0 100644 --- a/libbb/xfuncs.c +++ b/libbb/xfuncs.c @@ -182,3 +182,37 @@ void bb_xfflush_stdout(void) } } #endif + +#ifdef L_spawn +// This does a fork/exec in one call, using vfork(). +pid_t bb_spawn(char **argv) +{ + static int failed; + pid_t pid; + + // Be nice to nommu machines. + failed = 0; + pid = vfork(); + if (pid < 0) return pid; + if (!pid) { + execvp(*argv, argv); + + // We're sharing a stack with blocked parent, let parent know we failed + // and then exit to unblock parent (but don't run atexit() stuff, which + // would screw up parent.) + + failed = -1; + _exit(0); + } + return failed ? failed : pid; +} +#endif + +#ifdef L_xspawn +pid_t bb_xspawn(char **argv) +{ + pid_t pid = bb_spawn(argv); + if (pid < 0) bb_perror_msg_and_die("%s", *argv); + return pid; +} +#endif |