72be6a9da47223b2849b28c97c1427a7cb22df59
[paraslash.git] / afs_common.c
1 /*
2 * Copyright (C) 2005-2007 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7
8 /** \file afs_common.c Functions common to all audio file selectors. */
9
10 #include "para.h"
11 #include "server.cmdline.h"
12 #include "afh.h"
13 #include "server.h"
14 #include "vss.h"
15 #include <dirent.h> /* readdir() */
16 #include <sys/stat.h> /* stat */
17 #include <sys/types.h> /* mode_t */
18 #include "error.h"
19 #include "string.h"
20
21 /**
22 * Traverse the given directory recursively.
23 *
24 * \param dirname The directory to traverse.
25 * \param f The function to call for each entry.
26 *
27 * For each regular file whose filename ends in .yyy, where yyy is a supported
28 * audio format, the supplied function \a f is called. The directory and
29 * filename component of the regular file are passed to \a f.
30 *
31 * \return On success, 1 is returned. Otherwise, this function returns a
32 * negative value which indicates the kind of the error.
33 */
34 int find_audio_files(const char *dirname, int (*f)(const char *, const char *))
35 {
36 DIR *dir = NULL;
37 struct dirent *entry;
38 /*
39 * Opening the current directory (".") and calling fchdir() to return
40 * is usually faster and more reliable than saving cwd in some buffer
41 * and calling chdir() afterwards (see man 3 getcwd).
42 */
43 int cwd_fd = open(".", O_RDONLY);
44 struct stat s;
45 int ret;
46
47 if (cwd_fd < 0)
48 return -E_GETCWD;
49 ret = -E_CHDIR;
50 if (chdir(dirname) < 0)
51 goto out;
52 ret = -E_OPENDIR;
53 dir = opendir(".");
54 if (!dir)
55 goto out;
56 /* scan cwd recursively */
57 while ((entry = readdir(dir))) {
58 mode_t m;
59 char *tmp;
60
61 if (!strcmp(entry->d_name, "."))
62 continue;
63 if (!strcmp(entry->d_name, ".."))
64 continue;
65 ret = -E_LSTAT;
66 if (lstat(entry->d_name, &s) == -1)
67 continue;
68 m = s.st_mode;
69 if (!S_ISREG(m) && !S_ISDIR(m)) /* skip links, sockets, ... */
70 continue;
71 if (S_ISREG(m)) { /* regular file */
72 if (guess_audio_format(entry->d_name) < 0)
73 continue;
74 ret = f(dirname, entry->d_name);
75 if (ret < 0)
76 goto out;
77 continue;
78 }
79 /* directory */
80 tmp = make_message("%s/%s", dirname, entry->d_name);
81 ret = find_audio_files(tmp, f);
82 free(tmp);
83 if (ret < 0)
84 goto out;
85 }
86 ret = 1;
87 out:
88 if (dir)
89 closedir(dir);
90 if (fchdir(cwd_fd) < 0)
91 ret = -E_CHDIR;
92 close(cwd_fd);
93 if (ret < 0)
94 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
95 return ret;
96 }