-EMBEDDING THE LIBEV CODE INTO YOUR OWN PROGRAMS
-
- Instead of building the libev library you can also include the code
- as-is into your programs. To update, you only have to copy a few files
- into your source tree.
-
- This is how it works:
-
-FILESETS
-
- CORE EVENT LOOP
-
- To include only the libev core (all the ev_* functions):
-
- #define EV_STANDALONE 1
- #include "ev.c"
-
- This will automatically include ev.h, too, and should be done in a
- single C source file only to provide the function implementations. To
- use it, do the same for ev.h in all files wishing to use this API
- (best done by writing a wrapper around ev.h that you can include
- instead and where you can put other configuration options):
-
- #define EV_STANDALONE 1
- #include "ev.h"
-
- Both header files and implementation files can be compiled with a C++
- compiler (at least, thats a stated goal, and breakage will be treated
- as a bug).
-
- You need the following files in your source tree, or in a directory
- in your include path (e.g. in libev/ when using -Ilibev):
-
- ev.h
- ev.c
- ev_vars.h
- ev_wrap.h
- ev_win32.c
-
- ev_select.c only when select backend is enabled (which is is by default)
- ev_poll.c only when poll backend is enabled (disabled by default)
- ev_epoll.c only when the epoll backend is enabled (disabled by default)
- ev_kqueue.c only when the kqueue backend is enabled (disabled by default)
-
- "ev.c" includes the backend files directly when enabled.
-
- LIBEVENT COMPATIBILITY API
-
- To include the libevent compatibility API, also include:
-
- #include "event.c"
-
- in the file including "ev.c", and:
-
- #include "event.h"
-
- in the files that want to use the libevent API. This also includes "ev.h".
-
- You need the following additional files for this:
-
- event.h
- event.c
-
-AUTOCONF SUPPORT
-
- Instead of using EV_STANDALONE=1 and providing your config in whatever
- way you want, you can also m4_include([ev.m4]) in your configure.ac
- and leave EV_STANDALONE off. ev.c will then include "config.h" and
- configure itself accordingly.
-
-PREPROCESSOR SYMBOLS
-
- Libev can be configured via a variety of preprocessor symbols you have to define
- before including any of its files. The default is not to build for multiplicity
- and only include the select backend.
-
- EV_STANDALONE
-
- Must always be "1", which keeps libev from including config.h or
- other files, and it also defines dummy implementations for some
- libevent functions (such as logging, which is not supported). It
- will also not define any of the structs usually found in "event.h"
- that are not directly supported by libev code alone.
-
- EV_USE_MONOTONIC
-
- If undefined or defined to be "1", libev will try to detect the
- availability of the monotonic clock option at both compiletime and
- runtime. Otherwise no use of the monotonic clock option will be
- attempted.
-
- EV_USE_REALTIME
-
- If defined to be "1", libev will try to detect the availability
- of the realtime clock option at compiletime (and assume its
- availability at runtime if successful). Otherwise no use of the
- realtime clock option will be attempted. This effectively replaces
- gettimeofday by clock_get (CLOCK_REALTIME, ...) and will not normally
- affect correctness.
-
- EV_USE_SELECT
-
- If undefined or defined to be "1", libev will compile in support
- for the select(2) backend. No attempt at autodetection will be
- done: if no other method takes over, select will be it. Otherwise
- the select backend will not be compiled in.
-
- EV_SELECT_USE_WIN32_HANDLES
-
- When defined to 1, the select backend will assume that select
- doesn't understand file descriptors but wants osf handles on
- win32 (this is the case when the select to be used is the winsock
- select). This means that it will call _get_osfhandle on the fd to
- convert it to an OS handle. Should not be defined on non-win32
- platforms.
-
- EV_USE_POLL
-
- If defined to be "1", libev will compile in support for the poll(2)
- backend. No attempt at autodetection will be done. poll usually
- performs worse than select, so its not enabled by default (it is
- also slightly less portable).
-
- EV_USE_EPOLL
-
- If defined to be "1", libev will compile in support for the Linux
- epoll backend. Its availability will be detected at runtime,
- otherwise another method will be used as fallback. This is the
- preferred backend for GNU/Linux systems.
-
- EV_USE_KQUEUE
-
- If defined to be "1", libev will compile in support for the BSD
- style kqueue backend. Its availability will be detected at runtime,
- otherwise another method will be used as fallback. This is the
- preferred backend for BSD and BSd-like systems. Darwin brokenness
- will be detected at runtime and routed around by disabling this
- backend.
-
- EV_H
-
- The name of the ev.h header file used to include it. The default
- if undefined is <ev.h> in event.h and "ev.h" in ev.c. This can
- be used to virtually rename the ev.h header file in case of
- conflicts.
-
- EV_EVENT_H
-
- Similarly to EV_H, this macro cna be used to override event.c's idea
- of how the event.h header can be found.
-
- EV_COMMON
-
- By default, all watchers have a "void *data" member. By redefining
- this macro to a something else you can include more and other types
- of members. You have to define it each time you include one of the
- files, though, and it must be identical each time.
-
- For example, the perl EV module uses this:
-
- #define EV_COMMON \
- SV *self; /* contains this struct */ \
- SV *cb_sv, *fh /* note no trailing ";" */
-
- EV_PROTOTYPES
-
- If defined to be "0", then "ev.h" will not define any function
- prototypes, but still define all the structs and other
- symbols. This is occasionally useful.
-
- EV_MULTIPLICITY
-
- If undefined or defined to "1", then all event-loop-specific
- functions will have the "struct ev_loop *" as first argument, and
- you can create additional independent event loops. Otherwise there
- will be no support for multiple event loops and there is no first
- event loop pointer argument. Instead, all functions act on the
- single default loop.
-
- EV_CB_DECLARE(type)
- EV_CB_INVOKE(watcher,revents)
- ev_set_cb(ev,cb)
-
- Can be used to change the callback member declaration in each
- watcher, and the way callbacks are invoked and set. Must expand
- to a struct member definition and a statement, respectively. See
- the ev.v header file for their default definitions. One possible
- use for overriding these is to avoid the ev_loop pointer as first
- argument in all cases, or to use method calls instead of plain
- function calls in C++.
-
-EXAMPLES
-
- For a real-world example of a program the includes libev
- verbatim, you can have a look at the EV perl module
- (http://software.schmorp.de/pkg/EV.html). It has the libev files in
- the libev/ subdirectory and includes them in the EV/EVAPI.h (public
- interface) and EV.xs (implementation) files. Only the EV.xs file will
- be compiled.