105436638acc7c010349a69c3395f1a57c642dc62Ying Wang/* dirname.c -- return all but the last element in a file name 205436638acc7c010349a69c3395f1a57c642dc62Ying Wang 305436638acc7c010349a69c3395f1a57c642dc62Ying Wang Copyright (C) 1990, 1998, 2000-2001, 2003-2006, 2009-2012 Free Software 405436638acc7c010349a69c3395f1a57c642dc62Ying Wang Foundation, Inc. 505436638acc7c010349a69c3395f1a57c642dc62Ying Wang 605436638acc7c010349a69c3395f1a57c642dc62Ying Wang This program is free software: you can redistribute it and/or modify 705436638acc7c010349a69c3395f1a57c642dc62Ying Wang it under the terms of the GNU General Public License as published by 805436638acc7c010349a69c3395f1a57c642dc62Ying Wang the Free Software Foundation; either version 3 of the License, or 905436638acc7c010349a69c3395f1a57c642dc62Ying Wang (at your option) any later version. 1005436638acc7c010349a69c3395f1a57c642dc62Ying Wang 1105436638acc7c010349a69c3395f1a57c642dc62Ying Wang This program is distributed in the hope that it will be useful, 1205436638acc7c010349a69c3395f1a57c642dc62Ying Wang but WITHOUT ANY WARRANTY; without even the implied warranty of 1305436638acc7c010349a69c3395f1a57c642dc62Ying Wang MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 1405436638acc7c010349a69c3395f1a57c642dc62Ying Wang GNU General Public License for more details. 1505436638acc7c010349a69c3395f1a57c642dc62Ying Wang 1605436638acc7c010349a69c3395f1a57c642dc62Ying Wang You should have received a copy of the GNU General Public License 1705436638acc7c010349a69c3395f1a57c642dc62Ying Wang along with this program. If not, see <http://www.gnu.org/licenses/>. */ 1805436638acc7c010349a69c3395f1a57c642dc62Ying Wang 1905436638acc7c010349a69c3395f1a57c642dc62Ying Wang#include <config.h> 2005436638acc7c010349a69c3395f1a57c642dc62Ying Wang 2105436638acc7c010349a69c3395f1a57c642dc62Ying Wang#include "dirname.h" 2205436638acc7c010349a69c3395f1a57c642dc62Ying Wang 2305436638acc7c010349a69c3395f1a57c642dc62Ying Wang#include <stdlib.h> 2405436638acc7c010349a69c3395f1a57c642dc62Ying Wang#include <string.h> 2505436638acc7c010349a69c3395f1a57c642dc62Ying Wang 2605436638acc7c010349a69c3395f1a57c642dc62Ying Wang/* Return the length of the prefix of FILE that will be used by 2705436638acc7c010349a69c3395f1a57c642dc62Ying Wang dir_name. If FILE is in the working directory, this returns zero 2805436638acc7c010349a69c3395f1a57c642dc62Ying Wang even though 'dir_name (FILE)' will return ".". Works properly even 2905436638acc7c010349a69c3395f1a57c642dc62Ying Wang if there are trailing slashes (by effectively ignoring them). */ 3005436638acc7c010349a69c3395f1a57c642dc62Ying Wang 3105436638acc7c010349a69c3395f1a57c642dc62Ying Wangsize_t 3205436638acc7c010349a69c3395f1a57c642dc62Ying Wangdir_len (char const *file) 3305436638acc7c010349a69c3395f1a57c642dc62Ying Wang{ 3405436638acc7c010349a69c3395f1a57c642dc62Ying Wang size_t prefix_length = FILE_SYSTEM_PREFIX_LEN (file); 3505436638acc7c010349a69c3395f1a57c642dc62Ying Wang size_t length; 3605436638acc7c010349a69c3395f1a57c642dc62Ying Wang 3705436638acc7c010349a69c3395f1a57c642dc62Ying Wang /* Advance prefix_length beyond important leading slashes. */ 3805436638acc7c010349a69c3395f1a57c642dc62Ying Wang prefix_length += (prefix_length != 0 3905436638acc7c010349a69c3395f1a57c642dc62Ying Wang ? (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE 4005436638acc7c010349a69c3395f1a57c642dc62Ying Wang && ISSLASH (file[prefix_length])) 4105436638acc7c010349a69c3395f1a57c642dc62Ying Wang : (ISSLASH (file[0]) 4205436638acc7c010349a69c3395f1a57c642dc62Ying Wang ? ((DOUBLE_SLASH_IS_DISTINCT_ROOT 4305436638acc7c010349a69c3395f1a57c642dc62Ying Wang && ISSLASH (file[1]) && ! ISSLASH (file[2]) 4405436638acc7c010349a69c3395f1a57c642dc62Ying Wang ? 2 : 1)) 4505436638acc7c010349a69c3395f1a57c642dc62Ying Wang : 0)); 4605436638acc7c010349a69c3395f1a57c642dc62Ying Wang 4705436638acc7c010349a69c3395f1a57c642dc62Ying Wang /* Strip the basename and any redundant slashes before it. */ 4805436638acc7c010349a69c3395f1a57c642dc62Ying Wang for (length = last_component (file) - file; 4905436638acc7c010349a69c3395f1a57c642dc62Ying Wang prefix_length < length; length--) 5005436638acc7c010349a69c3395f1a57c642dc62Ying Wang if (! ISSLASH (file[length - 1])) 5105436638acc7c010349a69c3395f1a57c642dc62Ying Wang break; 5205436638acc7c010349a69c3395f1a57c642dc62Ying Wang return length; 5305436638acc7c010349a69c3395f1a57c642dc62Ying Wang} 5405436638acc7c010349a69c3395f1a57c642dc62Ying Wang 5505436638acc7c010349a69c3395f1a57c642dc62Ying Wang 5605436638acc7c010349a69c3395f1a57c642dc62Ying Wang/* In general, we can't use the builtin 'dirname' function if available, 5705436638acc7c010349a69c3395f1a57c642dc62Ying Wang since it has different meanings in different environments. 5805436638acc7c010349a69c3395f1a57c642dc62Ying Wang In some environments the builtin 'dirname' modifies its argument. 5905436638acc7c010349a69c3395f1a57c642dc62Ying Wang 6005436638acc7c010349a69c3395f1a57c642dc62Ying Wang Return the leading directories part of FILE, allocated with malloc. 6105436638acc7c010349a69c3395f1a57c642dc62Ying Wang Works properly even if there are trailing slashes (by effectively 6205436638acc7c010349a69c3395f1a57c642dc62Ying Wang ignoring them). Return NULL on failure. 6305436638acc7c010349a69c3395f1a57c642dc62Ying Wang 6405436638acc7c010349a69c3395f1a57c642dc62Ying Wang If lstat (FILE) would succeed, then { chdir (dir_name (FILE)); 6505436638acc7c010349a69c3395f1a57c642dc62Ying Wang lstat (base_name (FILE)); } will access the same file. Likewise, 6605436638acc7c010349a69c3395f1a57c642dc62Ying Wang if the sequence { chdir (dir_name (FILE)); 6705436638acc7c010349a69c3395f1a57c642dc62Ying Wang rename (base_name (FILE), "foo"); } succeeds, you have renamed FILE 6805436638acc7c010349a69c3395f1a57c642dc62Ying Wang to "foo" in the same directory FILE was in. */ 6905436638acc7c010349a69c3395f1a57c642dc62Ying Wang 7005436638acc7c010349a69c3395f1a57c642dc62Ying Wangchar * 7105436638acc7c010349a69c3395f1a57c642dc62Ying Wangmdir_name (char const *file) 7205436638acc7c010349a69c3395f1a57c642dc62Ying Wang{ 7305436638acc7c010349a69c3395f1a57c642dc62Ying Wang size_t length = dir_len (file); 7405436638acc7c010349a69c3395f1a57c642dc62Ying Wang bool append_dot = (length == 0 7505436638acc7c010349a69c3395f1a57c642dc62Ying Wang || (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE 7605436638acc7c010349a69c3395f1a57c642dc62Ying Wang && length == FILE_SYSTEM_PREFIX_LEN (file) 7705436638acc7c010349a69c3395f1a57c642dc62Ying Wang && file[2] != '\0' && ! ISSLASH (file[2]))); 7805436638acc7c010349a69c3395f1a57c642dc62Ying Wang char *dir = malloc (length + append_dot + 1); 7905436638acc7c010349a69c3395f1a57c642dc62Ying Wang if (!dir) 8005436638acc7c010349a69c3395f1a57c642dc62Ying Wang return NULL; 8105436638acc7c010349a69c3395f1a57c642dc62Ying Wang memcpy (dir, file, length); 8205436638acc7c010349a69c3395f1a57c642dc62Ying Wang if (append_dot) 8305436638acc7c010349a69c3395f1a57c642dc62Ying Wang dir[length++] = '.'; 8405436638acc7c010349a69c3395f1a57c642dc62Ying Wang dir[length] = '\0'; 8505436638acc7c010349a69c3395f1a57c642dc62Ying Wang return dir; 8605436638acc7c010349a69c3395f1a57c642dc62Ying Wang} 87