inotify_watch.h Source File

00001 #ifndef INOTIFY_WATCH_H
00002 #define INOTIFY_WATCH_H
00003 
00004 
00005 /*****************************************************************************/
00006 /******************************** Documentation ******************************/
00007 /*****************************************************************************/
00008 
00009 /**
00010  * \file
00011  * Public interface for inotify backend to log watch.
00012  */
00013 
00014 /*****************************************************************************/
00015 /******************************* Include Files *******************************/
00016 /*****************************************************************************/
00017 
00018 #include "lwatch.h"
00019 
00020 /*****************************************************************************/
00021 /*********************************** Defines *********************************/
00022 /*****************************************************************************/
00023 
00024 /**
00025  * Base error code (minimum value) for inotify watch errors
00026  */
00027 #define INOTIFY_WATCH_ERROR_BASE -2500
00028 /**
00029  * Maximum error code for inotify errors
00030  */
00031 #define INOTIFY_WATCH_ERROR_LIMIT (INOTIFY_WATCH_ERROR_BASE + 50)
00032 /**
00033  * Return true if error code is within the range for inotify watch errors.
00034  *
00035  * \param[in] error The error code to test if it's a inotify watch error code.
00036  * \return    True if error code is a inotify watch error.
00037  */
00038 #define IS_INOTIFY_WATCH_ERROR(error)  (((error) >= INOTIFY_WATCH_ERROR_BASE) && ((error) < INOTIFY_WATCH_ERROR_LIMIT))
00039 
00040 #define INOTIFY_WATCH_ERROR_NULL_WATCH         (INOTIFY_WATCH_ERROR_BASE + 1) /**< watch invalid, was NULL */
00041 #define INOTIFY_WATCH_ERROR_WATCH_ID_NOT_FOUND (INOTIFY_WATCH_ERROR_BASE + 2) /**< could not look up watch id */
00042 #define INOTIFY_WATCH_ALREADY_WATCHING         (INOTIFY_WATCH_ERROR_BASE + 3) /**< already being watched */
00043 #define INOTIFY_WATCH_NOT_WATCHED              (INOTIFY_WATCH_ERROR_BASE + 4) /**< not being watched */
00044 
00045 /*****************************************************************************/
00046 /******************************* Type Definitions ****************************/
00047 /*****************************************************************************/
00048 
00049 /**
00050  * When a watch is established on a filesystem directory this struct is used to
00051  * track it. See \ref HowFilesAreWatchedDoc
00052  */
00053 struct path_watch_t {
00054     char path[PATH_MAX];                 /**<  the pathname the watch was established on */
00055     int watch_id;                        /**<  the id (e.g. handle) assigned by the watch
00056                                                subsystem to this watch. When the subsystem
00057                                                sends us a notification it will contain this id
00058                                                and we'll have to look up this stuct via that id. */
00059     hash_table_t *descendant_path_table; /**<  the set of non-existant descendants of this directory
00060                                                whose creation we have watch for */
00061 };
00062 
00063 
00064 /*****************************************************************************/
00065 /*************************  External Global Variables  ***********************/
00066 /*****************************************************************************/
00067 
00068 /**
00069  * Flag used to indicate if the read_events() loop should terminate or
00070  * continue.
00071  */
00072 extern bool keep_watching;
00073 
00074 /*****************************************************************************/
00075 /****************************  Exported Functions  ***************************/
00076 /*****************************************************************************/
00077 
00078 int inotify_watch_init(void);
00079 int inotify_watch_fini(void);
00080 bool is_watch_target(const char *path);
00081 bool is_path_watched(const char* path);
00082 const char *inotify_watch_error_string(int error);
00083 char *inotify_mask_string(unsigned int mask, const char *separator);
00084 char *path_watch_string(struct path_watch_t *pw);
00085 struct path_watch_t *find_watch_by_path(const char* path);
00086 struct path_watch_t *find_watch_by_watch_id(int watch_id);
00087 int inotify_start_monitoring(const char *path);
00088 int inotify_stop_monitoring(const char *path);
00089 int read_events(void);
00090 int get_inotify_fd(void);
00091 lwatch_event_callback_t register_lwatch_event_callback(lwatch_event_callback_t callback);
00092 
00093 
00094 #endif