diff options
| -rw-r--r-- | coreutils/nohup.c | 202 | ||||
| -rw-r--r-- | include/platform.h | 2 | ||||
| -rw-r--r-- | miscutils/crond.c | 15 |
3 files changed, 38 insertions, 181 deletions
diff --git a/coreutils/nohup.c b/coreutils/nohup.c index febaf547f..ea1c4c55a 100644 --- a/coreutils/nohup.c +++ b/coreutils/nohup.c @@ -1,185 +1,55 @@ -/* vi: set sw=4 ts=4: */ -/* nohup -- run a command immune to hangups, with output to a non-tty - Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc. - - Licensed under the GPL v2, see the file LICENSE in this tarball. - +/* vi:set ts=4: */ +/* nohup - invoke a utility immune to hangups. + * + * Busybox version based on nohup specification at + * http://www.opengroup.org/onlinepubs/007904975/utilities/sed.html + * + * Copyright 2006 Rob Landley <rob@landley.net> + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */ -/* Written by Jim Meyering */ -/* initial busybox port by Bernhard Fischer */ - -#include <stdio_ext.h> /* __fpending */ -#include <stdio.h> -#include <unistd.h> #include <fcntl.h> -#include <sys/types.h> -#include <signal.h> -#include <errno.h> - +#include <unistd.h> #include "busybox.h" -#define EXIT_CANNOT_INVOKE (126) -#define NOHUP_FAILURE (127) -#define EXIT_ENOENT NOHUP_FAILURE - - -#if defined F_GETFD && defined F_SETFD -static inline int set_cloexec_flag (int desc) +int nohup_main(int argc, char *argv[]) { - int flags = fcntl (desc, F_GETFD, 0); - if (0 <= flags) { - if (flags == (flags |= FD_CLOEXEC) || - fcntl (desc, F_SETFD, flags) != -1) { - return 0; - } - } - return -1; -} -#else -#define set_cloexec_flag(desc) (0) -#endif - -static int fd_reopen (int desired_fd, char const *file, int flags) -{ - int fd; - - close (desired_fd); - fd = open (file, flags | O_WRONLY, S_IRUSR | S_IWUSR); - if (fd == desired_fd || fd < 0) - return fd; - else { - int fd2 = fcntl (fd, F_DUPFD, desired_fd); - int saved_errno = errno; - close (fd); - errno = saved_errno; - return fd2; - } -} - + int temp, nullfd; + char *nohupout = "nohup.out", *home = NULL; -/* Close standard output, exiting with status 'exit_failure' on failure. - If a program writes *anything* to stdout, that program should close - stdout and make sure that it succeeds before exiting. Otherwise, - suppose that you go to the extreme of checking the return status - of every function that does an explicit write to stdout. The last - printf can succeed in writing to the internal stream buffer, and yet - the fclose(stdout) could still fail (due e.g., to a disk full error) - when it tries to write out that buffered data. Thus, you would be - left with an incomplete output file and the offending program would - exit successfully. Even calling fflush is not always sufficient, - since some file systems (NFS and CODA) buffer written/flushed data - until an actual close call. + if (argc<2) bb_show_usage(); - Besides, it's wasteful to check the return value from every call - that writes to stdout -- just let the internal stream state record - the failure. That's what the ferror test is checking below. + nullfd = bb_xopen(bb_dev_null, O_WRONLY|O_APPEND); + // If stdin is a tty, detach from it. - It's important to detect such failures and exit nonzero because many - tools (most notably `make' and other build-management systems) depend - on being able to detect failure in other tools via their exit status. */ - -static void close_stdout (void) -{ - int prev_fail = ferror (stdout); - int none_pending = (0 == __fpending (stdout)); - int fclose_fail = fclose (stdout); + if (isatty(0)) dup2(nullfd, 0); - if (prev_fail || fclose_fail) { - /* If ferror returned zero, no data remains to be flushed, and we'd - otherwise fail with EBADF due to a failed fclose, then assume that - it's ok to ignore the fclose failure. That can happen when a - program like cp is invoked like this `cp a b >&-' (i.e., with - stdout closed) and doesn't generate any output (hence no previous - error and nothing to be flushed). */ - if ((fclose_fail ? errno : 0) == EBADF && !prev_fail && none_pending) - return; + // Redirect stdout to nohup.out, either in "." or in "$HOME". - bb_perror_msg_and_die(bb_msg_write_error); - } -} - - -int nohup_main (int argc, char **argv) -{ - int saved_stderr_fd; - - if (argc < 2) - bb_show_usage(); - - bb_default_error_retval = NOHUP_FAILURE; - - atexit (close_stdout); - - /* If standard input is a tty, replace it with /dev/null. - Note that it is deliberately opened for *writing*, - to ensure any read evokes an error. */ - if (isatty (STDIN_FILENO)) - fd_reopen (STDIN_FILENO, bb_dev_null, 0); - - /* If standard output is a tty, redirect it (appending) to a file. - First try nohup.out, then $HOME/nohup.out. */ - if (isatty (STDOUT_FILENO)) { - char *in_home = NULL; - char const *file = "nohup.out"; - int fd = fd_reopen (STDOUT_FILENO, file, O_CREAT | O_APPEND); - - if (fd < 0) { - if ((in_home = getenv ("HOME")) != NULL) { - in_home = concat_path_file(in_home, file); - fd = fd_reopen (STDOUT_FILENO, in_home, O_CREAT | O_APPEND); + if (isatty(1)) { + close(1); + if (open(nohupout, O_CREAT|O_WRONLY|O_APPEND, S_IRUSR|S_IWUSR) < 0) { + home = getenv("HOME"); + if (home) { + home = concat_path_file(home, nohupout); + bb_xopen3(nohupout, O_CREAT|O_WRONLY|O_APPEND, S_IRUSR|S_IWUSR); } - if (fd < 0) { - bb_perror_msg("failed to open '%s'", file); - if (in_home) - bb_perror_msg("failed to open '%s'",in_home); - return (NOHUP_FAILURE); - } - file = in_home; - } - - umask (~(S_IRUSR | S_IWUSR)); - bb_error_msg("appending output to '%s'", file); - if (ENABLE_FEATURE_CLEAN_UP) - free (in_home); - } - - /* If standard error is a tty, redirect it to stdout. */ - if (isatty (STDERR_FILENO)) { - /* Save a copy of stderr before redirecting, so we can use the original - if execve fails. It's no big deal if this dup fails. It might - not change anything, and at worst, it'll lead to suppression of - the post-failed-execve diagnostic. */ - saved_stderr_fd = dup (STDERR_FILENO); - - if (0 <= saved_stderr_fd && set_cloexec_flag (saved_stderr_fd) == -1) - bb_perror_msg_and_die("failed to set the copy" - "of stderr to close on exec"); - - if (dup2 (STDOUT_FILENO, STDERR_FILENO) < 0) { - if (errno != EBADF) - bb_perror_msg_and_die("failed to redirect standard error"); - close (STDERR_FILENO); } - } else - saved_stderr_fd = STDERR_FILENO; + } else dup2(nullfd, 1); - signal (SIGHUP, SIG_IGN); + // If we have a tty on strderr, announce filename and redirect to stdout. + // Else redirect to /dev/null. - { - char **cmd = argv + 1; + temp = isatty(2); + if (temp) fdprintf(2,"Writing to %s\n", home ? home : nohupout); + dup2(temp ? 1 : nullfd, 2); - execvp (*cmd, cmd); + close(nullfd); - /* The execve failed. Output a diagnostic to stderr only if: - - stderr was initially redirected to a non-tty, or - - stderr was initially directed to a tty, and we - can dup2 it to point back to that same tty. - In other words, output the diagnostic if possible, but only if - it will go to the original stderr. */ - if (dup2 (saved_stderr_fd, STDERR_FILENO) == STDERR_FILENO) - bb_perror_msg("cannot run command '%s'",*cmd); + // Exec our new program. - return (errno == ENOENT ? EXIT_ENOENT : EXIT_CANNOT_INVOKE); - } + execvp(argv[1],argv+1); + if (ENABLE_FEATURE_CLEAN_UP) free(home); + bb_error_msg_and_die("exec %s",argv[1]); } diff --git a/include/platform.h b/include/platform.h index 8bebb234e..62b4efba9 100644 --- a/include/platform.h +++ b/include/platform.h @@ -105,4 +105,6 @@ #define _(Text) Text #define N_(Text) (Text) +#define fdprintf(...) dprintf(__VA_ARGS__) + #endif /* platform.h */ diff --git a/miscutils/crond.c b/miscutils/crond.c index 9b194d13a..030e962f3 100644 --- a/miscutils/crond.c +++ b/miscutils/crond.c @@ -283,21 +283,6 @@ int crond_main(int ac, char **av) bb_fflush_stdout_and_exit(EXIT_SUCCESS); /* not reached */ } -#if ENABLE_DEBUG_CROND_OPTION || ENABLE_FEATURE_CROND_CALL_SENDMAIL -/* - write to temp file.. -*/ -static void fdprintf(int fd, const char *ctl, ...) -{ - va_list va; - - va_start(va, ctl); - vdprintf(fd, ctl, va); - va_end(va); -} -#endif - - static int ChangeUser(const char *user) { struct passwd *pas; |