1 /* $LP: LPlib/source/LPdir_unix.c,v 1.11 2004/09/23 22:07:22 _cvs_levitte Exp $ */ 2 /* 3 * Copyright (c) 2004, Richard Levitte <richard (at) levitte.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 18 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 19 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 21 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include <stddef.h> 29 #include <stdlib.h> 30 #include <limits.h> 31 #include <string.h> 32 #include <sys/types.h> 33 #include <dirent.h> 34 #include <errno.h> 35 #ifndef LPDIR_H 36 #include "LPdir.h" 37 #endif 38 39 /* The POSIXly macro for the maximum number of characters in a file path 40 is NAME_MAX. However, some operating systems use PATH_MAX instead. 41 Therefore, it seems natural to first check for PATH_MAX and use that, 42 and if it doesn't exist, use NAME_MAX. */ 43 #if defined(PATH_MAX) 44 # define LP_ENTRY_SIZE PATH_MAX 45 #elif defined(NAME_MAX) 46 # define LP_ENTRY_SIZE NAME_MAX 47 #endif 48 49 /* Of course, there's the possibility that neither PATH_MAX nor NAME_MAX 50 exist. It's also possible that NAME_MAX exists but is define to a 51 very small value (HP-UX offers 14), so we need to check if we got a 52 result, and if it meets a minimum standard, and create or change it 53 if not. */ 54 #if !defined(LP_ENTRY_SIZE) || LP_ENTRY_SIZE<255 55 # undef LP_ENTRY_SIZE 56 # define LP_ENTRY_SIZE 255 57 #endif 58 59 struct LP_dir_context_st 60 { 61 DIR *dir; 62 char entry_name[LP_ENTRY_SIZE+1]; 63 }; 64 65 const char *LP_find_file(LP_DIR_CTX **ctx, const char *directory) 66 { 67 struct dirent *direntry = NULL; 68 69 if (ctx == NULL || directory == NULL) 70 { 71 errno = EINVAL; 72 return 0; 73 } 74 75 errno = 0; 76 if (*ctx == NULL) 77 { 78 *ctx = (LP_DIR_CTX *)malloc(sizeof(LP_DIR_CTX)); 79 if (*ctx == NULL) 80 { 81 errno = ENOMEM; 82 return 0; 83 } 84 memset(*ctx, '\0', sizeof(LP_DIR_CTX)); 85 86 (*ctx)->dir = opendir(directory); 87 if ((*ctx)->dir == NULL) 88 { 89 int save_errno = errno; /* Probably not needed, but I'm paranoid */ 90 free(*ctx); 91 *ctx = NULL; 92 errno = save_errno; 93 return 0; 94 } 95 } 96 97 direntry = readdir((*ctx)->dir); 98 if (direntry == NULL) 99 { 100 return 0; 101 } 102 103 strncpy((*ctx)->entry_name, direntry->d_name, sizeof((*ctx)->entry_name) - 1); 104 (*ctx)->entry_name[sizeof((*ctx)->entry_name) - 1] = '\0'; 105 return (*ctx)->entry_name; 106 } 107 108 int LP_find_file_end(LP_DIR_CTX **ctx) 109 { 110 if (ctx != NULL && *ctx != NULL) 111 { 112 int ret = closedir((*ctx)->dir); 113 114 free(*ctx); 115 switch (ret) 116 { 117 case 0: 118 return 1; 119 case -1: 120 return 0; 121 default: 122 break; 123 } 124 } 125 errno = EINVAL; 126 return 0; 127 } 128
