coreutils/ln.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini ln implementation for busybox
   4  *
   5  * Copyright (C) 1999,2000 by Lineo, inc.
   6  * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21  *
  22  */
  23
  24 #include "internal.h"
  25 #define BB_DECLARE_EXTERN
  26 #define bb_need_name_too_long
  27 #define bb_need_not_a_directory
  28 #include "messages.c"
  29
  30 #include <stdio.h>
  31 #include <dirent.h>
  32 #include <errno.h>
  33
  34 static const char ln_usage[] =
  35         "ln [OPTION] TARGET... LINK_NAME|DIRECTORY\n"
  36 #ifndef BB_FEATURE_TRIVIAL_HELP
  37         "\nCreate a link named LINK_NAME or DIRECTORY to the specified TARGET\n"
  38         "\nYou may use '--' to indicate that all following arguments are non-options.\n\n"
  39         "Options:\n"
  40         "\t-s\tmake symbolic links instead of hard links\n"
  41
  42         "\t-f\tremove existing destination files\n"
  43 #if 0
  44         "\t-n\tno dereference symlinks - treat like normal file\n"
  45 #endif
  46 #endif
  47         ;
  48
  49 static int symlinkFlag = FALSE;
  50 static int removeoldFlag = FALSE;
  51 static int followLinks = TRUE;
  52
  53 extern int ln_main(int argc, char **argv)
  54 {
  55         char *linkName, *dirName;
  56         int linkIntoDirFlag;
  57         int stopIt = FALSE;
  58
  59         argc--;
  60         argv++;
  61
  62         /* Parse any options */
  63         while (argc > 0 && stopIt == FALSE) {
  64                 if (**argv == '-') {
  65                         while (*++(*argv))
  66                                 switch (**argv) {
  67                                         case 's':
  68                                                 symlinkFlag = TRUE;
  69                                                 break;
  70                                         case 'f':
  71                                                 removeoldFlag = TRUE;
  72                                                 break;
  73                                         case 'n':
  74                                                 followLinks = FALSE;
  75                                                 break;
  76                                         case '-':
  77                                                 stopIt = TRUE;
  78                                                 break;
  79                                         default:
  80                                                 usage(ln_usage);
  81                                 }
  82                         argc--;
  83                         argv++;
  84                 }
  85                 else
  86                         break;
  87         }
  88
  89         if (argc < 2) {
  90                 usage(ln_usage);
  91         }
  92
  93         linkName = argv[argc - 1];
  94
  95         if (strlen(linkName) > BUFSIZ) {
  96                 fprintf(stderr, name_too_long, "ln");
  97                 exit FALSE;
  98         }
  99
 100         linkIntoDirFlag = isDirectory(linkName, TRUE, NULL);
 101
 102         if ((argc >= 3) && linkIntoDirFlag == FALSE) {
 103                 fprintf(stderr, not_a_directory, "ln", linkName);
 104                 exit FALSE;
 105         }
 106
 107         if (linkIntoDirFlag == TRUE)
 108                 dirName = linkName;
 109
 110         while (argc-- >= 2) {
 111 #if 0
 112                 char srcName[BUFSIZ + 1];
 113                 int nChars;
 114 #endif
 115                 int status;
 116
 117                 if (strlen(*argv) > BUFSIZ) {
 118                         fprintf(stderr, name_too_long, "ln");
 119                         exit FALSE;
 120                 }
 121
 122 #if 0
 123                 if (followLinks == FALSE) {
 124                         strcpy(srcName, *argv);
 125                 } else {
 126                         /* Warning!  This can silently truncate if > BUFSIZ, but
 127                            I don't think that there can be one > BUFSIZ anyway. */
 128                         nChars = readlink(*argv, srcName, BUFSIZ);
 129                         srcName[nChars] = '\0';
 130                 }
 131 #endif
 132                 if (linkIntoDirFlag == TRUE) {
 133                         char *baseName = get_last_path_component(*argv);
 134                         linkName = (char *)malloc(strlen(dirName)+strlen(baseName)+2);
 135                         strcpy(linkName, dirName);
 136                         if(dirName[strlen(dirName)-1] != '/')
 137                                 strcat(linkName, "/");
 138                         strcat(linkName,baseName);
 139                 }
 140
 141                 if (removeoldFlag == TRUE) {
 142                         status = (unlink(linkName) && errno != ENOENT);
 143                         if (status != 0) {
 144                                 perror(linkName);
 145                                 exit FALSE;
 146                         }
 147                 }
 148
 149                 if (symlinkFlag == TRUE)
 150                         status = symlink(*argv, linkName);
 151                 else
 152                         status = link(*argv, linkName);
 153                 if (status != 0) {
 154                         perror(linkName);
 155                         exit FALSE;
 156                 }
 157
 158                 if (linkIntoDirFlag)
 159                         free(linkName);
 160
 161                 argv++;
 162         }
 163         return( TRUE);
 164 }
 165
 166 /*
 167 Local Variables:
 168 c-file-style: "linux"
 169 c-basic-offset: 4
 170 tab-width: 4
 171 End:
 172 */