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Diffstat (limited to 'nuttx/lib/unistd/lib_chdir.c')
-rw-r--r-- | nuttx/lib/unistd/lib_chdir.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/nuttx/lib/unistd/lib_chdir.c b/nuttx/lib/unistd/lib_chdir.c new file mode 100644 index 000000000..15dc64383 --- /dev/null +++ b/nuttx/lib/unistd/lib_chdir.c @@ -0,0 +1,179 @@ +/**************************************************************************** + * lib/unistd/lib_chdir.c + * + * Copyright (C) 2008-2009, 2011 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <spudmonkey@racsa.co.cr> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <sys/stat.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <errno.h> + +#include "lib_internal.h" + +#if CONFIG_NFILE_DESCRIPTORS > 0 && !defined(CONFIG_DISABLE_ENVIRON) + +/**************************************************************************** + * Public Variables + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: _trimdir + ****************************************************************************/ + +#if 0 +static inline void _trimdir(char *path) +{ + /* Skip any trailing '/' characters (unless it is also the leading '/') */ + + int len = strlen(path) - 1; + while (len > 0 && path[len] == '/') + { + path[len] = '\0'; + len--; + } +} +#else +# define _trimdir(p) +#endif + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: chdir + * + * Description: + * The chdir() function causes the directory named by the pathname pointed + * to by the 'path' argument to become the current working directory; that + * is, the starting point for path searches for pathnames not beginning + * with '/'. + * + * Input Parmeters: + * path - A pointer to a directory to use as the new current working + * directory + * + * Returned Value: + * 0(OK) on success; -1(ERROR) on failure with errno set appropriately: + * + * EACCES + * Search permission is denied for any component of the pathname. + * ELOOP + * A loop exists in symbolic links encountered during resolution of the + * 'path' argument OR more that SYMLOOP_MAX symbolic links in the + * resolution of the 'path' argument. + * ENAMETOOLONG + * The length of the path argument exceeds PATH_MAX or a pathname component + * is longer than NAME_MAX. + * ENOENT + * A component of 'path' does not name an existing directory or path is + * an empty string. + * ENOTDIR + * A component of the pathname is not a directory. + * + ****************************************************************************/ + +int chdir(FAR const char *path) +{ + struct stat buf; + char *oldpwd; + char *alloc; + int err; + int ret; + + /* Verify the input parameters */ + + if (!path) + { + err = ENOENT; + goto errout; + } + + /* Verify that 'path' refers to a directory */ + + ret = stat(path, &buf); + if (ret != 0) + { + err = ENOENT; + goto errout; + } + + /* Something exists here... is it a directory? */ + + if (!S_ISDIR(buf.st_mode)) + { + err = ENOTDIR; + goto errout; + } + + /* Yes, it is a directory. Remove any trailing '/' characters from the path */ + + _trimdir(path); + + /* Replace any preceding OLDPWD with the current PWD (this is to + * support 'cd -' in NSH) + */ + + sched_lock(); + oldpwd = getenv("PWD"); + if (!oldpwd) + { + oldpwd = CONFIG_LIB_HOMEDIR; + } + + alloc = strdup(oldpwd); /* kludge needed because environment is realloc'ed */ + setenv("OLDPWD", alloc, TRUE); + free(alloc); + + /* Set the cwd to the input 'path' */ + + setenv("PWD", path, TRUE); + sched_unlock(); + return OK; + +errout: + errno = err; + return ERROR; +} +#endif /* CONFIG_NFILE_DESCRIPTORS && !CONFIG_DISABLE_ENVIRON */ |