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