… | |
… | |
1184 | #include <stddef.h> |
1184 | #include <stddef.h> |
1185 | |
1185 | |
1186 | static void |
1186 | static void |
1187 | t1_cb (EV_P_ ev_timer *w, int revents) |
1187 | t1_cb (EV_P_ ev_timer *w, int revents) |
1188 | { |
1188 | { |
1189 | struct my_biggy big = (struct my_biggy * |
1189 | struct my_biggy big = (struct my_biggy *) |
1190 | (((char *)w) - offsetof (struct my_biggy, t1)); |
1190 | (((char *)w) - offsetof (struct my_biggy, t1)); |
1191 | } |
1191 | } |
1192 | |
1192 | |
1193 | static void |
1193 | static void |
1194 | t2_cb (EV_P_ ev_timer *w, int revents) |
1194 | t2_cb (EV_P_ ev_timer *w, int revents) |
1195 | { |
1195 | { |
1196 | struct my_biggy big = (struct my_biggy * |
1196 | struct my_biggy big = (struct my_biggy *) |
1197 | (((char *)w) - offsetof (struct my_biggy, t2)); |
1197 | (((char *)w) - offsetof (struct my_biggy, t2)); |
1198 | } |
1198 | } |
1199 | |
1199 | |
1200 | =head2 WATCHER PRIORITY MODELS |
1200 | =head2 WATCHER PRIORITY MODELS |
1201 | |
1201 | |
… | |
… | |
1277 | // with the default priority are receiving events. |
1277 | // with the default priority are receiving events. |
1278 | ev_idle_start (EV_A_ &idle); |
1278 | ev_idle_start (EV_A_ &idle); |
1279 | } |
1279 | } |
1280 | |
1280 | |
1281 | static void |
1281 | static void |
1282 | idle-cb (EV_P_ ev_idle *w, int revents) |
1282 | idle_cb (EV_P_ ev_idle *w, int revents) |
1283 | { |
1283 | { |
1284 | // actual processing |
1284 | // actual processing |
1285 | read (STDIN_FILENO, ...); |
1285 | read (STDIN_FILENO, ...); |
1286 | |
1286 | |
1287 | // have to start the I/O watcher again, as |
1287 | // have to start the I/O watcher again, as |
… | |
… | |
1523 | C<after> argument to C<ev_timer_set>, and only ever use the C<repeat> |
1523 | C<after> argument to C<ev_timer_set>, and only ever use the C<repeat> |
1524 | member and C<ev_timer_again>. |
1524 | member and C<ev_timer_again>. |
1525 | |
1525 | |
1526 | At start: |
1526 | At start: |
1527 | |
1527 | |
1528 | ev_timer_init (timer, callback); |
1528 | ev_init (timer, callback); |
1529 | timer->repeat = 60.; |
1529 | timer->repeat = 60.; |
1530 | ev_timer_again (loop, timer); |
1530 | ev_timer_again (loop, timer); |
1531 | |
1531 | |
1532 | Each time there is some activity: |
1532 | Each time there is some activity: |
1533 | |
1533 | |
… | |
… | |
1595 | |
1595 | |
1596 | To start the timer, simply initialise the watcher and set C<last_activity> |
1596 | To start the timer, simply initialise the watcher and set C<last_activity> |
1597 | to the current time (meaning we just have some activity :), then call the |
1597 | to the current time (meaning we just have some activity :), then call the |
1598 | callback, which will "do the right thing" and start the timer: |
1598 | callback, which will "do the right thing" and start the timer: |
1599 | |
1599 | |
1600 | ev_timer_init (timer, callback); |
1600 | ev_init (timer, callback); |
1601 | last_activity = ev_now (loop); |
1601 | last_activity = ev_now (loop); |
1602 | callback (loop, timer, EV_TIMEOUT); |
1602 | callback (loop, timer, EV_TIMEOUT); |
1603 | |
1603 | |
1604 | And when there is some activity, simply store the current time in |
1604 | And when there is some activity, simply store the current time in |
1605 | C<last_activity>, no libev calls at all: |
1605 | C<last_activity>, no libev calls at all: |
… | |
… | |
2368 | // no longer anything immediate to do. |
2368 | // no longer anything immediate to do. |
2369 | } |
2369 | } |
2370 | |
2370 | |
2371 | ev_idle *idle_watcher = malloc (sizeof (ev_idle)); |
2371 | ev_idle *idle_watcher = malloc (sizeof (ev_idle)); |
2372 | ev_idle_init (idle_watcher, idle_cb); |
2372 | ev_idle_init (idle_watcher, idle_cb); |
2373 | ev_idle_start (loop, idle_cb); |
2373 | ev_idle_start (loop, idle_watcher); |
2374 | |
2374 | |
2375 | |
2375 | |
2376 | =head2 C<ev_prepare> and C<ev_check> - customise your event loop! |
2376 | =head2 C<ev_prepare> and C<ev_check> - customise your event loop! |
2377 | |
2377 | |
2378 | Prepare and check watchers are usually (but not always) used in pairs: |
2378 | Prepare and check watchers are usually (but not always) used in pairs: |
… | |
… | |
2471 | struct pollfd fds [nfd]; |
2471 | struct pollfd fds [nfd]; |
2472 | // actual code will need to loop here and realloc etc. |
2472 | // actual code will need to loop here and realloc etc. |
2473 | adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ())); |
2473 | adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ())); |
2474 | |
2474 | |
2475 | /* the callback is illegal, but won't be called as we stop during check */ |
2475 | /* the callback is illegal, but won't be called as we stop during check */ |
2476 | ev_timer_init (&tw, 0, timeout * 1e-3); |
2476 | ev_timer_init (&tw, 0, timeout * 1e-3, 0.); |
2477 | ev_timer_start (loop, &tw); |
2477 | ev_timer_start (loop, &tw); |
2478 | |
2478 | |
2479 | // create one ev_io per pollfd |
2479 | // create one ev_io per pollfd |
2480 | for (int i = 0; i < nfd; ++i) |
2480 | for (int i = 0; i < nfd; ++i) |
2481 | { |
2481 | { |
… | |
… | |
3935 | way (note also that glib is the slowest event library known to man). |
3935 | way (note also that glib is the slowest event library known to man). |
3936 | |
3936 | |
3937 | There is no supported compilation method available on windows except |
3937 | There is no supported compilation method available on windows except |
3938 | embedding it into other applications. |
3938 | embedding it into other applications. |
3939 | |
3939 | |
|
|
3940 | Sensible signal handling is officially unsupported by Microsoft - libev |
|
|
3941 | tries its best, but under most conditions, signals will simply not work. |
|
|
3942 | |
3940 | Not a libev limitation but worth mentioning: windows apparently doesn't |
3943 | Not a libev limitation but worth mentioning: windows apparently doesn't |
3941 | accept large writes: instead of resulting in a partial write, windows will |
3944 | accept large writes: instead of resulting in a partial write, windows will |
3942 | either accept everything or return C<ENOBUFS> if the buffer is too large, |
3945 | either accept everything or return C<ENOBUFS> if the buffer is too large, |
3943 | so make sure you only write small amounts into your sockets (less than a |
3946 | so make sure you only write small amounts into your sockets (less than a |
3944 | megabyte seems safe, but this apparently depends on the amount of memory |
3947 | megabyte seems safe, but this apparently depends on the amount of memory |
… | |
… | |
3948 | the abysmal performance of winsockets, using a large number of sockets |
3951 | the abysmal performance of winsockets, using a large number of sockets |
3949 | is not recommended (and not reasonable). If your program needs to use |
3952 | is not recommended (and not reasonable). If your program needs to use |
3950 | more than a hundred or so sockets, then likely it needs to use a totally |
3953 | more than a hundred or so sockets, then likely it needs to use a totally |
3951 | different implementation for windows, as libev offers the POSIX readiness |
3954 | different implementation for windows, as libev offers the POSIX readiness |
3952 | notification model, which cannot be implemented efficiently on windows |
3955 | notification model, which cannot be implemented efficiently on windows |
3953 | (Microsoft monopoly games). |
3956 | (due to Microsoft monopoly games). |
3954 | |
3957 | |
3955 | A typical way to use libev under windows is to embed it (see the embedding |
3958 | A typical way to use libev under windows is to embed it (see the embedding |
3956 | section for details) and use the following F<evwrap.h> header file instead |
3959 | section for details) and use the following F<evwrap.h> header file instead |
3957 | of F<ev.h>: |
3960 | of F<ev.h>: |
3958 | |
3961 | |
… | |
… | |
3994 | |
3997 | |
3995 | Early versions of winsocket's select only supported waiting for a maximum |
3998 | Early versions of winsocket's select only supported waiting for a maximum |
3996 | of C<64> handles (probably owning to the fact that all windows kernels |
3999 | of C<64> handles (probably owning to the fact that all windows kernels |
3997 | can only wait for C<64> things at the same time internally; Microsoft |
4000 | can only wait for C<64> things at the same time internally; Microsoft |
3998 | recommends spawning a chain of threads and wait for 63 handles and the |
4001 | recommends spawning a chain of threads and wait for 63 handles and the |
3999 | previous thread in each. Great). |
4002 | previous thread in each. Sounds great!). |
4000 | |
4003 | |
4001 | Newer versions support more handles, but you need to define C<FD_SETSIZE> |
4004 | Newer versions support more handles, but you need to define C<FD_SETSIZE> |
4002 | to some high number (e.g. C<2048>) before compiling the winsocket select |
4005 | to some high number (e.g. C<2048>) before compiling the winsocket select |
4003 | call (which might be in libev or elsewhere, for example, perl does its own |
4006 | call (which might be in libev or elsewhere, for example, perl and many |
4004 | select emulation on windows). |
4007 | other interpreters do their own select emulation on windows). |
4005 | |
4008 | |
4006 | Another limit is the number of file descriptors in the Microsoft runtime |
4009 | Another limit is the number of file descriptors in the Microsoft runtime |
4007 | libraries, which by default is C<64> (there must be a hidden I<64> fetish |
4010 | libraries, which by default is C<64> (there must be a hidden I<64> |
4008 | or something like this inside Microsoft). You can increase this by calling |
4011 | fetish or something like this inside Microsoft). You can increase this |
4009 | C<_setmaxstdio>, which can increase this limit to C<2048> (another |
4012 | by calling C<_setmaxstdio>, which can increase this limit to C<2048> |
4010 | arbitrary limit), but is broken in many versions of the Microsoft runtime |
4013 | (another arbitrary limit), but is broken in many versions of the Microsoft |
4011 | libraries. |
|
|
4012 | |
|
|
4013 | This might get you to about C<512> or C<2048> sockets (depending on |
4014 | runtime libraries. This might get you to about C<512> or C<2048> sockets |
4014 | windows version and/or the phase of the moon). To get more, you need to |
4015 | (depending on windows version and/or the phase of the moon). To get more, |
4015 | wrap all I/O functions and provide your own fd management, but the cost of |
4016 | you need to wrap all I/O functions and provide your own fd management, but |
4016 | calling select (O(n²)) will likely make this unworkable. |
4017 | the cost of calling select (O(n²)) will likely make this unworkable. |
4017 | |
4018 | |
4018 | =back |
4019 | =back |
4019 | |
4020 | |
4020 | =head2 PORTABILITY REQUIREMENTS |
4021 | =head2 PORTABILITY REQUIREMENTS |
4021 | |
4022 | |