From 373c95c45ae5ac72a585bbec1ffb6185da84f29d Mon Sep 17 00:00:00 2001 From: Jim Meyering Date: Wed, 21 Mar 2007 09:09:34 +0100 Subject: * gl/lib/savewd.c: Remove this file, since the savewd_save change is now in gnulib. The other wasn't useful. --- gl/lib/savewd.c | 308 -------------------------------------------------------- 1 file changed, 308 deletions(-) delete mode 100644 gl/lib/savewd.c (limited to 'gl') diff --git a/gl/lib/savewd.c b/gl/lib/savewd.c deleted file mode 100644 index a6ee23517..000000000 --- a/gl/lib/savewd.c +++ /dev/null @@ -1,308 +0,0 @@ -/* Save and restore the working directory, possibly using a child process. - - Copyright (C) 2006, 2007 Free Software Foundation, Inc. - - 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, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ - -/* Written by Paul Eggert. */ - -#include - -#include "savewd.h" - -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "dirname.h" -#include "fcntl-safer.h" - - -/* Save the working directory into *WD, if it hasn't been saved - already. Return true if a child has been forked to do the real - work. */ -static bool -savewd_save (struct savewd *wd) -{ - switch (wd->state) - { - case INITIAL_STATE: - /* Save the working directory, or prepare to fall back if possible. */ - { - int fd = open_safer (".", O_RDONLY); - if (0 <= fd) - { - wd->state = FD_STATE; - wd->val.fd = fd; - break; - } - if (errno != EACCES && errno != ESTALE) - { - wd->state = ERROR_STATE; - wd->val.errnum = errno; - break; - } - } - wd->state = FORKING_STATE; - wd->val.child = -1; - /* Fall through. */ - case FORKING_STATE: - if (wd->val.child < 0) - { - /* "Save" the initial working directory by forking a new - subprocess that will attempt all the work from the chdir - until until the next savewd_restore. */ - wd->val.child = fork (); - if (wd->val.child != 0) - { - if (0 < wd->val.child) - return true; - wd->state = ERROR_STATE; - wd->val.errnum = errno; - } - } - break; - - case FD_STATE: - case FD_POST_CHDIR_STATE: - case ERROR_STATE: - case FINAL_STATE: - break; - - default: - assert (false); - } - - return false; -} - -int -savewd_chdir (struct savewd *wd, char const *dir, int options, - int open_result[2]) -{ - int fd = -1; - int result = 0; - - /* Open the directory if requested, or if avoiding a race condition - is requested and possible. */ - if (open_result - || (options & (HAVE_WORKING_O_NOFOLLOW ? SAVEWD_CHDIR_NOFOLLOW : 0))) - { - fd = open (dir, - (O_RDONLY | O_DIRECTORY | O_NOCTTY | O_NONBLOCK - | (options & SAVEWD_CHDIR_NOFOLLOW ? O_NOFOLLOW : 0))); - - if (open_result) - { - open_result[0] = fd; - open_result[1] = errno; - } - - if (fd < 0 && ((errno != EACCES && errno != ESTALE) - || (options & SAVEWD_CHDIR_READABLE))) - result = -1; - } - - if (result == 0 && ! (0 <= fd && options & SAVEWD_CHDIR_SKIP_READABLE)) - { - if (savewd_save (wd)) - { - open_result = NULL; - result = -2; - } - else - { - result = (fd < 0 ? chdir (dir) : fchdir (fd)); - - if (result == 0) - switch (wd->state) - { - case FD_STATE: - wd->state = FD_POST_CHDIR_STATE; - break; - - case ERROR_STATE: - case FD_POST_CHDIR_STATE: - case FINAL_STATE: - break; - - case FORKING_STATE: - assert (wd->val.child == 0); - break; - - default: - assert (false); - } - } - } - - if (0 <= fd && ! open_result) - { - int e = errno; - close (fd); - errno = e; - } - - return result; -} - -int -savewd_restore (struct savewd *wd, int status) -{ - switch (wd->state) - { - case INITIAL_STATE: - case FD_STATE: - /* The working directory is the desired directory, so there's no - work to do. */ - break; - - case FD_POST_CHDIR_STATE: - /* Restore the working directory using fchdir. */ - if (fchdir (wd->val.fd) == 0) - { - wd->state = FD_STATE; - break; - } - else - { - int chdir_errno = errno; - close (wd->val.fd); - wd->state = ERROR_STATE; - wd->val.errnum = chdir_errno; - } - /* Fall through. */ - case ERROR_STATE: - /* Report an error if asked to restore the working directory. */ - errno = wd->val.errnum; - return -1; - - case FORKING_STATE: - /* "Restore" the working directory by waiting for the subprocess - to finish. */ - { - pid_t child = wd->val.child; - if (child == 0) - _exit (status); - if (0 < child) - { - int child_status; - while (waitpid (child, &child_status, 0) < 0) - assert (errno == EINTR); - wd->val.child = -1; - if (! WIFEXITED (child_status)) - raise (WTERMSIG (child_status)); - return WEXITSTATUS (child_status); - } - } - break; - - default: - assert (false); - } - - return 0; -} - -void -savewd_finish (struct savewd *wd) -{ - switch (wd->state) - { - case INITIAL_STATE: - case ERROR_STATE: - break; - - case FD_STATE: - case FD_POST_CHDIR_STATE: - close (wd->val.fd); - break; - - case FORKING_STATE: - assert (wd->val.child < 0); - break; - - default: - assert (false); - } - - wd->state = FINAL_STATE; -} - -/* Return true if the actual work is currently being done by a - subprocess. - - A true return means that the caller and the subprocess should - resynchronize later with savewd_restore, using only their own - memory to decide when to resynchronize; they should not consult the - file system to decide, because that might lead to race conditions. - This is why savewd_chdir is broken out into another function; - savewd_chdir's callers _can_ inspect the file system to decide - whether to call savewd_chdir. */ -static inline bool -savewd_delegating (struct savewd const *wd) -{ - return wd->state == FORKING_STATE && 0 < wd->val.child; -} - -int -savewd_process_files (int n_files, char **file, - int (*act) (char *, struct savewd *, void *), - void *options) -{ - int i = 0; - int last_relative; - int exit_status = EXIT_SUCCESS; - struct savewd wd; - savewd_init (&wd); - - for (last_relative = n_files - 1; 0 <= last_relative; last_relative--) - if (! IS_ABSOLUTE_FILE_NAME (file[last_relative])) - break; - - for (; i < last_relative; i++) - { - if (! savewd_delegating (&wd)) - { - int s = act (file[i], &wd, options); - if (exit_status < s) - exit_status = s; - } - - if (! IS_ABSOLUTE_FILE_NAME (file[i + 1])) - { - int r = savewd_restore (&wd, exit_status); - if (exit_status < r) - exit_status = r; - } - } - - savewd_finish (&wd); - - for (; i < n_files; i++) - { - int s = act (file[i], &wd, options); - if (exit_status < s) - exit_status = s; - } - - return exit_status; -} -- cgit v1.2.3-54-g00ecf