X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;f=ucw%2Fmainloop.h;h=6e8ffae6d3704bb3114ffb5c70ca7559c51a8e0e;hb=7bd1bf513e4047f2314807ad3f65c0b4ed383328;hp=c19d53ad04b0db03d0c4ad357145216c575012b1;hpb=9d837d7ff2e97b72b51f4781148d2e079ad77769;p=libucw.git diff --git a/ucw/mainloop.h b/ucw/mainloop.h index c19d53ad..6e8ffae6 100644 --- a/ucw/mainloop.h +++ b/ucw/mainloop.h @@ -1,7 +1,7 @@ /* * UCW Library -- Main Loop * - * (c) 2004--2011 Martin Mares + * (c) 2004--2012 Martin Mares * * This software may be freely distributed and used according to the terms * of the GNU Lesser General Public License. @@ -10,10 +10,56 @@ #ifndef _UCW_MAINLOOP_H #define _UCW_MAINLOOP_H -#include "ucw/clists.h" +#include +#include #include +#ifdef CONFIG_UCW_CLEAN_ABI +#define block_io_add ucw_block_io_add +#define block_io_del ucw_block_io_del +#define block_io_read ucw_block_io_read +#define block_io_set_timeout ucw_block_io_set_timeout +#define block_io_write ucw_block_io_write +#define file_add ucw_file_add +#define file_chg ucw_file_chg +#define file_debug ucw_file_debug +#define file_del ucw_file_del +#define hook_add ucw_hook_add +#define hook_debug ucw_hook_debug +#define hook_del ucw_hook_del +#define main_cleanup ucw_main_cleanup +#define main_current ucw_main_current +#define main_debug_context ucw_main_debug_context +#define main_delete ucw_main_delete +#define main_destroy ucw_main_destroy +#define main_get_time ucw_main_get_time +#define main_init ucw_main_init +#define main_loop ucw_main_loop +#define main_new ucw_main_new +#define main_step ucw_main_step +#define main_switch_context ucw_main_switch_context +#define main_teardown ucw_main_teardown +#define process_add ucw_process_add +#define process_debug ucw_process_debug +#define process_del ucw_process_del +#define process_fork ucw_process_fork +#define rec_io_add ucw_rec_io_add +#define rec_io_del ucw_rec_io_del +#define rec_io_parse_line ucw_rec_io_parse_line +#define rec_io_set_timeout ucw_rec_io_set_timeout +#define rec_io_start_read ucw_rec_io_start_read +#define rec_io_stop_read ucw_rec_io_stop_read +#define rec_io_write ucw_rec_io_write +#define signal_add ucw_signal_add +#define signal_debug ucw_signal_debug +#define signal_del ucw_signal_del +#define timer_add ucw_timer_add +#define timer_add_rel ucw_timer_add_rel +#define timer_debug ucw_timer_debug +#define timer_del ucw_timer_del +#endif + /*** * [[basic]] * Basic operations @@ -24,24 +70,23 @@ /** The main loop context **/ struct main_context { - timestamp_t now; /* [*] Current time in milliseconds since the UNIX epoch. See main_get_time(). */ - ucw_time_t now_seconds; /* [*] Current time in seconds since the epoch. */ + timestamp_t now; /* [*] Current time in milliseconds since an unknown epoch. See main_get_time(). */ timestamp_t idle_time; /* [*] Total time in milliseconds spent by waiting for events. */ - uns shutdown; /* [*] Setting this to nonzero forces the main_loop() function to terminate. */ + uint shutdown; /* [*] Setting this to nonzero forces the main_loop() function to terminate. */ clist file_list; clist file_active_list; clist hook_list; clist hook_done_list; clist process_list; clist signal_list; - uns file_cnt; - uns single_step; + uint file_cnt; + uint single_step; #ifdef CONFIG_UCW_EPOLL int epoll_fd; /* File descriptor used for epoll */ struct epoll_event *epoll_events; clist file_recalc_list; #else - uns poll_table_obsolete; + uint poll_table_obsolete; struct pollfd *poll_table; struct main_file **poll_file_table; #endif @@ -111,12 +156,11 @@ static inline void main_shut_down(void) /** * Show the current state of a given context (use @main_debug() for the current context). - * Available only if LibUCW has been compiled with `CONFIG_DEBUG`. + * Available only if LibUCW has been compiled with `CONFIG_UCW_DEBUG`. **/ void main_debug_context(struct main_context *m); -static inline void -main_debug(void) +static inline void main_debug(void) { main_debug_context(main_current()); } @@ -143,12 +187,6 @@ static inline timestamp_t main_get_now(void) return main_current()->now; } -/** An analog of @main_get_now() returning the number of seconds since the system epoch. **/ -static inline ucw_time_t main_get_now_seconds(void) -{ - return main_current()->now_seconds; -} - /** * This is a description of a timer. * You define the handler function and possibly user-defined data you wish @@ -157,7 +195,7 @@ static inline ucw_time_t main_get_now_seconds(void) struct main_timer { cnode n; timestamp_t expires; - uns index; + uint index; void (*handler)(struct main_timer *tm); /* [*] Function to be called when the timer expires. */ void *data; /* [*] Data for use by the handler */ }; @@ -168,7 +206,8 @@ struct main_timer { * timer. It is permitted (and usual) to call this function from the * timer's handler itself if you want the timer to trigger again. * - * The @expire parameter is absolute, use @timer_add_rel() for a relative version. + * The @expire parameter is absolute (in the same time scale as @main_get_now()), + * use @timer_add_rel() for a relative version. **/ void timer_add(struct main_timer *tm, timestamp_t expires); @@ -178,10 +217,16 @@ void timer_add_rel(struct main_timer *tm, timestamp_t expires_delta); /** * Removes a timer from the active ones. It is permitted (and common) to call * this function from the timer's handler itself if you want to deactivate - * the timer. + * the timer. Removing an already removed timer does nothing. **/ void timer_del(struct main_timer *tm); +/** Tells whether a timer is running. **/ +static inline int timer_is_active(struct main_timer *tm) +{ + return !!tm->expires; +} + /** * Forces refresh of the current timestamp cached in the active context. * You usually do not need to call this, since it is called every time the @@ -190,9 +235,79 @@ void timer_del(struct main_timer *tm); **/ void main_get_time(void); -/** Show current state of a timer. Available only if LibUCW has been compiled with `CONFIG_DEBUG`. **/ +/** Show current state of a timer. Available only if LibUCW has been compiled with `CONFIG_UCW_DEBUG`. **/ void timer_debug(struct main_timer *tm); +/*** + * [[hooks]] + * Loop hooks + * ---------- + * + * The hooks are called whenever the main loop performs an iteration. + * You can shutdown the main loop from within them or request an iteration + * to happen without sleeping (just poll, no waiting for events). + ***/ + +/** + * A hook. It contains the function to call and some user data. + * + * The handler() must return one value from + * <>. + * + * Fill with the hook and data and pass it to @hook_add(). + **/ +struct main_hook { + cnode n; + int (*handler)(struct main_hook *ho); /* [*] Hook function; returns HOOK_xxx */ + void *data; /* [*] For use by the handler */ +}; + +/** + * Return value of the hook handler(). + * Specifies what should happen next. + * + * - `HOOK_IDLE` -- Let the loop sleep until something happens, call after that. + * - `HOOK_RETRY` -- Force the loop to perform another iteration without sleeping. + * This will cause calling of all the hooks again soon. + * - `HOOK_DONE` -- The loop will terminate if all hooks return this. + * - `HOOK_SHUTDOWN` -- Shuts down the loop. + * + * The `HOOK_IDLE` and `HOOK_RETRY` constants are also used as return values + * of file handlers. + **/ +enum main_hook_return { + HOOK_IDLE, + HOOK_RETRY, + HOOK_DONE = -1, + HOOK_SHUTDOWN = -2 +}; + +/** + * Inserts a new hook into the loop. + * The hook will be scheduled at least once before next sleep. + * May be called from inside a hook handler too. + * Adding an already added hook is permitted and if the hook has been run, + * it will be run again before next sleep. + **/ +void hook_add(struct main_hook *ho); + +/** + * Removes an existing hook from the loop. + * May be called from inside a hook handler (to delete itself or another hook). + * Removing an already removed hook does nothing. + **/ +void hook_del(struct main_hook *ho); + +/** Tells if a hook is active (i.e., added). **/ +static inline int hook_is_active(struct main_hook *ho) +{ + return clist_is_linked(&ho->n); +} + +/** Show current state of a hook. Available only if LibUCW has been compiled with `CONFIG_UCW_DEBUG`. **/ +void hook_debug(struct main_hook *ho); + + /*** * [[file]] * Activity on file descriptors @@ -236,9 +351,9 @@ struct main_file { int (*read_handler)(struct main_file *fi); /* [*] To be called when ready for reading/writing; must call file_chg() afterwards */ int (*write_handler)(struct main_file *fi); void *data; /* [*] Data for use by the handlers */ - uns events; + uint events; #ifdef CONFIG_UCW_EPOLL - uns last_want_events; + uint last_want_events; #else struct pollfd *pollfd; #endif @@ -266,10 +381,17 @@ void file_chg(struct main_file *fi); * please use this function first. * * Can be called from a handler. + * Removing an already removed file does nothing. **/ void file_del(struct main_file *fi); -/** Show current state of a file. Available only if LibUCW has been compiled with `CONFIG_DEBUG`. **/ +/** Tells if a file is active (i.e., added). **/ +static inline int file_is_active(struct main_file *fi) +{ + return clist_is_linked(&fi->n); +} + +/** Show current state of a file. Available only if LibUCW has been compiled with `CONFIG_UCW_DEBUG`. **/ void file_debug(struct main_file *fi); /*** @@ -299,9 +421,9 @@ void file_debug(struct main_file *fi); struct main_block_io { struct main_file file; byte *rbuf; /* Read/write pointers for use by file_read/write */ - uns rpos, rlen; + uint rpos, rlen; byte *wbuf; - uns wpos, wlen; + uint wpos, wlen; void (*read_done)(struct main_block_io *bio); /* [*] Called when file_read is finished; rpos < rlen if EOF */ void (*write_done)(struct main_block_io *bio); /* [*] Called when file_write is finished */ void (*error_handler)(struct main_block_io *bio, int cause); /* [*] Handler to call on errors */ @@ -312,7 +434,7 @@ struct main_block_io { /** Activate a block I/O structure. **/ void block_io_add(struct main_block_io *bio, int fd); -/** Deactivate a block I/O structure. **/ +/** Deactivate a block I/O structure. Calling twice is safe. **/ void block_io_del(struct main_block_io *bio); /** @@ -340,7 +462,7 @@ enum block_io_err_cause { * You can use a call with zero @len to cancel the current read, but all read data * will be thrown away. **/ -void block_io_read(struct main_block_io *bio, void *buf, uns len); +void block_io_read(struct main_block_io *bio, void *buf, uint len); /** * Request that the main loop writes @len bytes of data from @buf to @bio. @@ -353,7 +475,7 @@ void block_io_read(struct main_block_io *bio, void *buf, uns len); * If you call it with zero @len, it will cancel the previous write, but note * that some data may already be written. **/ -void block_io_write(struct main_block_io *bio, void *buf, uns len); +void block_io_write(struct main_block_io *bio, void *buf, uint len); /** * Sets a timer for a file @bio. If the timer is not overwritten or disabled @@ -371,12 +493,45 @@ void block_io_write(struct main_block_io *bio, void *buf, uns len); **/ void block_io_set_timeout(struct main_block_io *bio, timestamp_t expires_delta); +/** Tells if a @bio is active (i.e., added). **/ +static inline int block_io_is_active(struct main_block_io *bio) +{ + return file_is_active(&bio->file); +} + /*** * [[recordio]] * Asynchronous record I/O * ----------------------- * - * FIXME + * Record-based I/O is another front-end to the main loop file operations. + * Unlike its older cousin `main_block_io`, it is able to process records + * of variable length. + * + * To set it up, you create <> and call + * @rec_io_add() on it, which sets up some <>s internally. + * + * To read data from the file, call @rec_io_start_read() first. Whenever any data + * arrive from the file, they are appended to an internal buffer and the `read_handler` + * hook is called. The hook checks if the buffer already contains a complete record. + * If it is so, it processes the record and returns the number of bytes consumed. + * Otherwise, it returns 0 to tell the buffering machinery that more data are needed. + * When the read handler decides to destroy the `main_rec_io`, it must return `~0U`. + * + * On the write side, `main_rec_io` maintains a buffer keeping all data that should + * be written to the file. The @rec_io_write() function appends data to this buffer + * and it is written on background. A simple flow-control mechanism can be asked + * for: when more than `write_throttle_read` data are buffered for writing, reading + * is temporarily suspended. + * + * Additionally, the record I/O is equipped with a timer, which can be used + * to detect communication timeouts. The timer is not touched internally + * (except that it gets added and deleted at the right places), feel free + * to adjust it from your handler functions by @rec_io_set_timeout(). + * + * All important events are passed to the `notify_handler`: errors when + * reading or writing, timeouts, the write buffer becoming empty, ... See + * <> for a complete list. ***/ /** The record I/O structure. **/ @@ -384,47 +539,55 @@ struct main_rec_io { struct main_file file; byte *read_buf; byte *read_rec_start; /* [*] Start of current record */ - uns read_avail; /* [*] How much data is available */ - uns read_prev_avail; /* [*] How much data was available in previous read_handler */ - uns read_buf_size; /* [*] Read buffer size allocated (can be set before rec_io_add()) */ - uns read_started; /* Reading requested by user */ - uns read_running; /* Reading really runs (read_started && not stopped by write_throttle_read) */ - uns read_rec_max; /* [*] Maximum record size (0=unlimited) */ + uint read_avail; /* [*] How much data is available */ + uint read_prev_avail; /* [*] How much data was available in previous read_handler */ + uint read_buf_size; /* [*] Read buffer size allocated (can be set before rec_io_add()) */ + uint read_started; /* Reading requested by user */ + uint read_running; /* Reading really runs (read_started && not stopped by write_throttle_read) */ + uint read_rec_max; /* [*] Maximum record size (0=unlimited) */ clist busy_write_buffers; clist idle_write_buffers; - uns write_buf_size; /* [*] Write buffer size allocated (can be set before rec_io_add()) */ - uns write_watermark; /* [*] How many data are waiting to be written */ - uns write_throttle_read; /* [*] If more than write_throttle_read bytes are buffered, stop reading; 0=no stopping */ - uns (*read_handler)(struct main_rec_io *rio); /* [*] Called whenever more bytes are read; returns 0 (want more) or number of bytes eaten */ + uint write_buf_size; /* [*] Write buffer size allocated (can be set before rec_io_add()) */ + uint write_watermark; /* [*] How much data are waiting to be written */ + uint write_throttle_read; /* [*] If more than write_throttle_read bytes are buffered, stop reading; 0=no stopping */ + uint (*read_handler)(struct main_rec_io *rio); /* [*] Called whenever more bytes are read; returns 0 (want more) or number of bytes eaten */ int (*notify_handler)(struct main_rec_io *rio, int status); /* [*] Called to notify about errors and other events */ /* Returns either HOOK_RETRY or HOOK_IDLE. */ struct main_timer timer; + struct main_hook start_read_hook; /* Used internally to defer rec_io_start_read() */ void *data; /* [*] Data for use by the handlers */ }; /** Activate a record I/O structure. **/ void rec_io_add(struct main_rec_io *rio, int fd); -/** Deactivate a record I/O structure. **/ +/** Deactivate a record I/O structure. Calling twice is safe. **/ void rec_io_del(struct main_rec_io *rio); -/** Start reading. **/ +/** + * Start reading. + * + * When there were some data in the buffer (e.g., because @rec_io_stop_read() + * was called from the `read_handler`), it is processed as if it were read + * from the file once again. That is, `read_prev_avail` is reset to 0 and + * the `read_handler` is called to process all buffered data. + ***/ void rec_io_start_read(struct main_rec_io *rio); /** Stop reading. **/ void rec_io_stop_read(struct main_rec_io *rio); /** Analogous to @block_io_set_timeout(). **/ -void rec_io_set_timeout(struct main_rec_io *bio, timestamp_t expires_delta); +void rec_io_set_timeout(struct main_rec_io *rio, timestamp_t expires_delta); -void rec_io_write(struct main_rec_io *rio, void *data, uns len); +void rec_io_write(struct main_rec_io *rio, void *data, uint len); /** * An auxiliary function used for parsing of lines. When called in the @read_handler, * it searches for the end of line character. When a complete line is found, the length * of the line (including the end of line character) is returned. Otherwise, it returns zero. **/ -uns rec_io_parse_line(struct main_rec_io *rio); +uint rec_io_parse_line(struct main_rec_io *rio); /** * Specifies what kind of error or other event happened, when the @notify_handler @@ -447,65 +610,11 @@ enum rec_io_notify_status { RIO_EVENT_EOF = 3, /* Read: EOF seen */ }; -/*** - * [[hooks]] - * Loop hooks - * ---------- - * - * The hooks are called whenever the main loop performs an iteration. - * You can shutdown the main loop from within them or request an iteration - * to happen without sleeping (just poll, no waiting for events). - ***/ - -/** - * A hook. It contains the function to call and some user data. - * - * The handler() must return one value from - * <>. - * - * Fill with the hook and data and pass it to @hook_add(). - **/ -struct main_hook { - cnode n; - int (*handler)(struct main_hook *ho); /* [*] Hook function; returns HOOK_xxx */ - void *data; /* [*] For use by the handler */ -}; - -/** - * Return value of the hook handler(). - * Specifies what should happen next. - * - * - `HOOK_IDLE` -- Let the loop sleep until something happens, call after that. - * - `HOOK_RETRY` -- Force the loop to perform another iteration without sleeping. - * This will cause calling of all the hooks again soon. - * - `HOOK_DONE` -- The loop will terminate if all hooks return this. - * - `HOOK_SHUTDOWN` -- Shuts down the loop. - * - * The `HOOK_IDLE` and `HOOK_RETRY` constants are also used as return values - * of file handlers. - **/ -enum main_hook_return { - HOOK_IDLE, - HOOK_RETRY, - HOOK_DONE = -1, - HOOK_SHUTDOWN = -2 -}; - -/** - * Inserts a new hook into the loop. - * The hook will be scheduled at least once before next sleep. - * May be called from inside a hook handler too. - **/ -void hook_add(struct main_hook *ho); - -/** - * Removes an existing hook from the loop. - * May be called from inside a hook handler (to delete itself or another hook). - **/ -void hook_del(struct main_hook *ho); - -/** Show current state of a hook. Available only if LibUCW has been compiled with `CONFIG_DEBUG`. **/ -void hook_debug(struct main_hook *ho); +/** Tells if a @rio is active (i.e., added). **/ +static inline int rec_io_is_active(struct main_rec_io *rio) +{ + return file_is_active(&rio->file); +} /*** * [[process]] @@ -541,6 +650,7 @@ void process_add(struct main_process *mp); * Removes the process from the watched set. This is done * automatically, when the process terminates, so you need it only * when you do not want to watch a running process any more. + * Removing an already removed process does nothing. */ void process_del(struct main_process *mp); @@ -560,7 +670,13 @@ void process_del(struct main_process *mp); **/ int process_fork(struct main_process *mp); -/** Show current state of a process. Available only if LibUCW has been compiled with `CONFIG_DEBUG`. **/ +/** Tells if a process is active (i.e., added). **/ +static inline int process_is_active(struct main_process *mp) +{ + return clist_is_linked(&mp->n); +} + +/** Show current state of a process. Available only if LibUCW has been compiled with `CONFIG_UCW_DEBUG`. **/ void process_debug(struct main_process *pr); /*** @@ -600,10 +716,16 @@ struct main_signal { /** Request a signal to be caught and delivered synchronously. **/ void signal_add(struct main_signal *ms); -/** Cancel a request for signal catching. **/ +/** Cancel a request for signal catching. Calling twice is safe. **/ void signal_del(struct main_signal *ms); -/** Show current state of a signal catcher. Available only if LibUCW has been compiled with `CONFIG_DEBUG`. **/ +/** Tells if a signal catcher is active (i.e., added). **/ +static inline int signal_is_active(struct main_signal *ms) +{ + return clist_is_linked(&ms->n); +} + +/** Show current state of a signal catcher. Available only if LibUCW has been compiled with `CONFIG_UCW_DEBUG`. **/ void signal_debug(struct main_signal *sg); #endif