Line data    Source code

       1             : /*
       2             :  * $LP: LPlib/source/LPdir_unix.c,v 1.11 2004/09/23 22:07:22 _cvs_levitte Exp
       3             :  * $
       4             :  */
       5             : /*
       6             :  * Copyright (c) 2004, Richard Levitte <richard@levitte.org>
       7             :  * All rights reserved.
       8             :  *
       9             :  * Redistribution and use in source and binary forms, with or without
      10             :  * modification, are permitted provided that the following conditions
      11             :  * are met:
      12             :  * 1. Redistributions of source code must retain the above copyright
      13             :  *    notice, this list of conditions and the following disclaimer.
      14             :  * 2. Redistributions in binary form must reproduce the above copyright
      15             :  *    notice, this list of conditions and the following disclaimer in the
      16             :  *    documentation and/or other materials provided with the distribution.
      17             :  *
      18             :  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
      19             :  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
      20             :  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
      21             :  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
      22             :  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
      23             :  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
      24             :  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      25             :  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      26             :  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      27             :  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
      28             :  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
      29             :  */
      30             : 
      31             : #include <stddef.h>
      32             : #include <stdlib.h>
      33             : #include <limits.h>
      34             : #include <string.h>
      35             : #include <sys/types.h>
      36             : #include <dirent.h>
      37             : #include <errno.h>
      38             : #ifndef LPDIR_H
      39             : # include "LPdir.h"
      40             : #endif
      41             : 
      42             : /*
      43             :  * The POSIXly macro for the maximum number of characters in a file path is
      44             :  * NAME_MAX.  However, some operating systems use PATH_MAX instead.
      45             :  * Therefore, it seems natural to first check for PATH_MAX and use that, and
      46             :  * if it doesn't exist, use NAME_MAX.
      47             :  */
      48             : #if defined(PATH_MAX)
      49             : # define LP_ENTRY_SIZE PATH_MAX
      50             : #elif defined(NAME_MAX)
      51             : # define LP_ENTRY_SIZE NAME_MAX
      52             : #endif
      53             : 
      54             : /*
      55             :  * Of course, there's the possibility that neither PATH_MAX nor NAME_MAX
      56             :  * exist.  It's also possible that NAME_MAX exists but is define to a very
      57             :  * small value (HP-UX offers 14), so we need to check if we got a result, and
      58             :  * if it meets a minimum standard, and create or change it if not.
      59             :  */
      60             : #if !defined(LP_ENTRY_SIZE) || LP_ENTRY_SIZE<255
      61             : # undef LP_ENTRY_SIZE
      62             : # define LP_ENTRY_SIZE 255
      63             : #endif
      64             : 
      65             : struct LP_dir_context_st {
      66             :     DIR *dir;
      67             :     char entry_name[LP_ENTRY_SIZE + 1];
      68             : };
      69             : 
      70           0 : const char *LP_find_file(LP_DIR_CTX **ctx, const char *directory)
      71             : {
      72             :     struct dirent *direntry = NULL;
      73             : 
      74           0 :     if (ctx == NULL || directory == NULL) {
      75           0 :         errno = EINVAL;
      76           0 :         return 0;
      77             :     }
      78             : 
      79           0 :     errno = 0;
      80           0 :     if (*ctx == NULL) {
      81           0 :         *ctx = (LP_DIR_CTX *)malloc(sizeof(LP_DIR_CTX));
      82           0 :         if (*ctx == NULL) {
      83           0 :             errno = ENOMEM;
      84           0 :             return 0;
      85             :         }
      86             :         memset(*ctx, '\0', sizeof(LP_DIR_CTX));
      87             : 
      88           0 :         (*ctx)->dir = opendir(directory);
      89           0 :         if ((*ctx)->dir == NULL) {
      90           0 :             int save_errno = errno; /* Probably not needed, but I'm paranoid */
      91           0 :             free(*ctx);
      92           0 :             *ctx = NULL;
      93           0 :             errno = save_errno;
      94           0 :             return 0;
      95             :         }
      96             :     }
      97             : 
      98           0 :     direntry = readdir((*ctx)->dir);
      99           0 :     if (direntry == NULL) {
     100             :         return 0;
     101             :     }
     102             : 
     103           0 :     strncpy((*ctx)->entry_name, direntry->d_name,
     104             :             sizeof((*ctx)->entry_name) - 1);
     105           0 :     (*ctx)->entry_name[sizeof((*ctx)->entry_name) - 1] = '\0';
     106           0 :     return (*ctx)->entry_name;
     107             : }
     108             : 
     109           0 : int LP_find_file_end(LP_DIR_CTX **ctx)
     110             : {
     111           0 :     if (ctx != NULL && *ctx != NULL) {
     112           0 :         int ret = closedir((*ctx)->dir);
     113             : 
     114           0 :         free(*ctx);
     115           0 :         switch (ret) {
     116             :         case 0:
     117             :             return 1;
     118             :         case -1:
     119           0 :             return 0;
     120             :         default:
     121             :             break;
     122             :         }
     123             :     }
     124           0 :     errno = EINVAL;
     125           0 :     return 0;
     126             : }