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@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
LP_find_file(LP_DIR_CTX ** ctx,const char * directory)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
LP_find_file_end(LP_DIR_CTX ** ctx)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