rename plm_dbtool.c to playlist_selector.c

[paraslash.git] / db.h

diff --git a/db.h b/db.h
index 34ea52d1d3423b678222332cea01e84afc22b122..578e4fd9f8ba33ef7626832cb58eb9655ee2d8cd 100644 (file)
--- a/db.h
+++ b/db.h
@@ -16,7 +16,10 @@
  *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  */
 
-/** \file db.h data structures common to all database tools */
+/** \file db.h data structures common to all audio file selectors */
+
+#include <sys/select.h>
+
 
 int find_audio_files(const char *dirname, int (*f)(const char *, const char *));
 
@@ -30,7 +33,7 @@ int find_audio_files(const char *dirname, int (*f)(const char *, const char *));
  *
  *
  */
-struct dbtool {
+struct audio_file_selector {
 /**
  * name name of this database tool
  */
@@ -46,13 +49,13 @@ const char *name;
  * again via the cdt command).
  *
  * If \a init() returns success (non-negative return value), it must have
- * initialized in all non-optional function pointers of the given dbtool
+ * initialized in all non-optional function pointers of the given selector
  * struct. Moreover, \a cmd_list must point to a NULL-terminated array which
  * holds the list of all commands that are supported by this database tool.
  */
-int (*init)(struct dbtool *self);
+int (*init)(struct audio_file_selector *self);
 /**
- * list of commands supported by this dbtool
+ * list of commands supported by this selector
  */
 struct server_command *cmd_list;
 /**
@@ -78,7 +81,7 @@ char **(*get_audio_file_list)(unsigned int num);
  * passed \a update_audio_file().
  *
  */
-void  (*update_audio_file)(char *audio_file);
+void (*update_audio_file)(char *audio_file);
 /**
  *
  * shutdown this database tool and free all resources
@@ -86,11 +89,36 @@ void  (*update_audio_file)(char *audio_file);
  * This gets called whenever the database tool changes (via the cdt command),
  * or when para_server receives the HUP signal, or when para_server shuts down.
  * It is assumed to succeed.
-*/
+ */
 void (*shutdown)(void);
+/**
+ *
+ * add file descriptors to fd_sets
+ *
+ * The pre_select function of the activated database tool gets called just
+ * before para_server enters its main select loop. The selector may add its own
+ * file descriptors to the \a rfds or the \a wfds set.
+ *
+ * If a file descriptor was added, \a max_fileno must be increased by
+ * this function, if neccessary.
+ *
+ * \sa select(2)
+ */
+int (*pre_select)(fd_set *rfds, fd_set *wfds);
+/**
+ * handle the file descriptors which are ready for I/O
+ *
+ * If the pre_select hook added one ore more file descriptors to the read or write
+ * set, this is the hook to check the result and do any I/O on those descriptors
+ * which are ready for reading/writing.
+ */
+void (*post_select)(fd_set *rfds, fd_set *wfds);
+/**
+ * each selector has its private data pointer */
+void *private_data;
 };
 
-int mysql_dbtool_init(struct dbtool*);
-int plm_dbtool_init(struct dbtool*);
-int random_dbtool_init(struct dbtool*);
+int mysql_selector_init(struct audio_file_selector*);
+int playlist_selector_init(struct audio_file_selector*);
+int random_selector_init(struct audio_file_selector*);