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| -rw-r--r-- | ev.3 | 285 | ||||
| -rw-r--r-- | ev.html | 23 |
2 files changed, 293 insertions, 15 deletions
@@ -1538,6 +1538,291 @@ the constructor. \& io.start (fd, ev::READ); \& } .Ve +.SH "EMBEDDING" +.IX Header "EMBEDDING" +Libev can (and often is) directly embedded into host +applications. Examples of applications that embed it include the Deliantra +Game Server, the \s-1EV\s0 perl module, the \s-1GNU\s0 Virtual Private Ethernet (gvpe) +and rxvt\-unicode. +.PP +The goal is to enable you to just copy the neecssary files into your +source directory without having to change even a single line in them, so +you can easily upgrade by simply copying (or having a checked-out copy of +libev somewhere in your source tree). +.Sh "\s-1FILESETS\s0" +.IX Subsection "FILESETS" +Depending on what features you need you need to include one or more sets of files +in your app. +.PP +\fI\s-1CORE\s0 \s-1EVENT\s0 \s-1LOOP\s0\fR +.IX Subsection "CORE EVENT LOOP" +.PP +To include only the libev core (all the \f(CW\*(C`ev_*\*(C'\fR functions), with manual +configuration (no autoconf): +.PP +.Vb 2 +\& #define EV_STANDALONE 1 +\& #include "ev.c" +.Ve +.PP +This will automatically include \fIev.h\fR, too, and should be done in a +single C source file only to provide the function implementations. To use +it, do the same for \fIev.h\fR in all files wishing to use this \s-1API\s0 (best +done by writing a wrapper around \fIev.h\fR that you can include instead and +where you can put other configuration options): +.PP +.Vb 2 +\& #define EV_STANDALONE 1 +\& #include "ev.h" +.Ve +.PP +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). +.PP +You need the following files in your source tree, or in a directory +in your include path (e.g. in libev/ when using \-Ilibev): +.PP +.Vb 4 +\& ev.h +\& ev.c +\& ev_vars.h +\& ev_wrap.h +.Ve +.PP +.Vb 1 +\& ev_win32.c required on win32 platforms only +.Ve +.PP +.Vb 5 +\& 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_port.c only when the solaris port backend is enabled (disabled by default) +.Ve +.PP +\&\fIev.c\fR includes the backend files directly when enabled, so you only need +to compile a single file. +.PP +\fI\s-1LIBEVENT\s0 \s-1COMPATIBILITY\s0 \s-1API\s0\fR +.IX Subsection "LIBEVENT COMPATIBILITY API" +.PP +To include the libevent compatibility \s-1API\s0, also include: +.PP +.Vb 1 +\& #include "event.c" +.Ve +.PP +in the file including \fIev.c\fR, and: +.PP +.Vb 1 +\& #include "event.h" +.Ve +.PP +in the files that want to use the libevent \s-1API\s0. This also includes \fIev.h\fR. +.PP +You need the following additional files for this: +.PP +.Vb 2 +\& event.h +\& event.c +.Ve +.PP +\fI\s-1AUTOCONF\s0 \s-1SUPPORT\s0\fR +.IX Subsection "AUTOCONF SUPPORT" +.PP +Instead of using \f(CW\*(C`EV_STANDALONE=1\*(C'\fR and providing your config in +whatever way you want, you can also \f(CW\*(C`m4_include([libev.m4])\*(C'\fR in your +\&\fIconfigure.ac\fR and leave \f(CW\*(C`EV_STANDALONE\*(C'\fR off. \fIev.c\fR will then include +\&\fIconfig.h\fR and configure itself accordingly. +.PP +For this of course you need the m4 file: +.PP +.Vb 1 +\& libev.m4 +.Ve +.Sh "\s-1PREPROCESSOR\s0 \s-1SYMBOLS/MACROS\s0" +.IX Subsection "PREPROCESSOR SYMBOLS/MACROS" +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. +.IP "\s-1EV_STANDALONE\s0" 4 +.IX Item "EV_STANDALONE" +Must always be \f(CW1\fR if you do not use autoconf configuration, which +keeps libev from including \fIconfig.h\fR, 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 +\&\fIevent.h\fR that are not directly supported by the libev core alone. +.IP "\s-1EV_USE_MONOTONIC\s0" 4 +.IX Item "EV_USE_MONOTONIC" +If defined to be \f(CW1\fR, 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. If you enable this, you +usually have to link against librt or something similar. Enabling it when +the functionality isn't available is safe, though, althoguh you have +to make sure you link against any libraries where the \f(CW\*(C`clock_gettime\*(C'\fR +function is hiding in (often \fI\-lrt\fR). +.IP "\s-1EV_USE_REALTIME\s0" 4 +.IX Item "EV_USE_REALTIME" +If defined to be \f(CW1\fR, 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 \f(CW\*(C`gettimeofday\*(C'\fR by \f(CW\*(C`clock_get +(CLOCK_REALTIME, ...)\*(C'\fR and will not normally affect correctness. See tzhe note about libraries +in the description of \f(CW\*(C`EV_USE_MONOTONIC\*(C'\fR, though. +.IP "\s-1EV_USE_SELECT\s0" 4 +.IX Item "EV_USE_SELECT" +If undefined or defined to be \f(CW1\fR, libev will compile in support for the +\&\f(CW\*(C`select\*(C'\fR(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. +.IP "\s-1EV_SELECT_USE_FD_SET\s0" 4 +.IX Item "EV_SELECT_USE_FD_SET" +If defined to \f(CW1\fR, then the select backend will use the system \f(CW\*(C`fd_set\*(C'\fR +structure. This is useful if libev doesn't compile due to a missing +\&\f(CW\*(C`NFDBITS\*(C'\fR or \f(CW\*(C`fd_mask\*(C'\fR definition or it misguesses the bitset layout on +exotic systems. This usually limits the range of file descriptors to some +low limit such as 1024 or might have other limitations (winsocket only +allows 64 sockets). The \f(CW\*(C`FD_SETSIZE\*(C'\fR macro, set before compilation, might +influence the size of the \f(CW\*(C`fd_set\*(C'\fR used. +.IP "\s-1EV_SELECT_IS_WINSOCKET\s0" 4 +.IX Item "EV_SELECT_IS_WINSOCKET" +When defined to \f(CW1\fR, the select backend will assume that +select/socket/connect etc. don'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 +\&\f(CW\*(C`_get_osfhandle\*(C'\fR on the fd to convert it to an \s-1OS\s0 handle. Otherwise, +it is assumed that all these functions actually work on fds, even +on win32. Should not be defined on non\-win32 platforms. +.IP "\s-1EV_USE_POLL\s0" 4 +.IX Item "EV_USE_POLL" +If defined to be \f(CW1\fR, libev will compile in support for the \f(CW\*(C`poll\*(C'\fR(2) +backend. Otherwise it will be enabled on non\-win32 platforms. It +takes precedence over select. +.IP "\s-1EV_USE_EPOLL\s0" 4 +.IX Item "EV_USE_EPOLL" +If defined to be \f(CW1\fR, libev will compile in support for the Linux +\&\f(CW\*(C`epoll\*(C'\fR(7) 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. +.IP "\s-1EV_USE_KQUEUE\s0" 4 +.IX Item "EV_USE_KQUEUE" +If defined to be \f(CW1\fR, libev will compile in support for the \s-1BSD\s0 style +\&\f(CW\*(C`kqueue\*(C'\fR(2) backend. Its actual availability will be detected at runtime, +otherwise another method will be used as fallback. This is the preferred +backend for \s-1BSD\s0 and BSD-like systems, although on most BSDs kqueue only +supports some types of fds correctly (the only platform we found that +supports ptys for example was NetBSD), so kqueue might be compiled in, but +not be used unless explicitly requested. The best way to use it is to find +out wether kqueue supports your type of fd properly and use an embedded +kqueue loop. +.IP "\s-1EV_USE_PORT\s0" 4 +.IX Item "EV_USE_PORT" +If defined to be \f(CW1\fR, libev will compile in support for the Solaris +10 port style backend. Its availability will be detected at runtime, +otherwise another method will be used as fallback. This is the preferred +backend for Solaris 10 systems. +.IP "\s-1EV_USE_DEVPOLL\s0" 4 +.IX Item "EV_USE_DEVPOLL" +reserved for future expansion, works like the \s-1USE\s0 symbols above. +.IP "\s-1EV_H\s0" 4 +.IX Item "EV_H" +The name of the \fIev.h\fR header file used to include it. The default if +undefined is \f(CW\*(C`<ev.h>\*(C'\fR in \fIevent.h\fR and \f(CW"ev.h"\fR in \fIev.c\fR. This +can be used to virtually rename the \fIev.h\fR header file in case of conflicts. +.IP "\s-1EV_CONFIG_H\s0" 4 +.IX Item "EV_CONFIG_H" +If \f(CW\*(C`EV_STANDALONE\*(C'\fR isn't \f(CW1\fR, this variable can be used to override +\&\fIev.c\fR's idea of where to find the \fIconfig.h\fR file, similarly to +\&\f(CW\*(C`EV_H\*(C'\fR, above. +.IP "\s-1EV_EVENT_H\s0" 4 +.IX Item "EV_EVENT_H" +Similarly to \f(CW\*(C`EV_H\*(C'\fR, this macro can be used to override \fIevent.c\fR's idea +of how the \fIevent.h\fR header can be found. +.IP "\s-1EV_PROTOTYPES\s0" 4 +.IX Item "EV_PROTOTYPES" +If defined to be \f(CW0\fR, then \fIev.h\fR will not define any function +prototypes, but still define all the structs and other symbols. This is +occasionally useful if you want to provide your own wrapper functions +around libev functions. +.IP "\s-1EV_MULTIPLICITY\s0" 4 +.IX Item "EV_MULTIPLICITY" +If undefined or defined to \f(CW1\fR, then all event-loop-specific functions +will have the \f(CW\*(C`struct ev_loop *\*(C'\fR 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. +.IP "\s-1EV_PERIODICS\s0" 4 +.IX Item "EV_PERIODICS" +If undefined or defined to be \f(CW1\fR, then periodic timers are supported, +otherwise not. This saves a few kb of code. +.IP "\s-1EV_COMMON\s0" 4 +.IX Item "EV_COMMON" +By default, all watchers have a \f(CW\*(C`void *data\*(C'\fR 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. +.Sp +For example, the perl \s-1EV\s0 module uses something like this: +.Sp +.Vb 3 +\& #define EV_COMMON \e +\& SV *self; /* contains this struct */ \e +\& SV *cb_sv, *fh /* note no trailing ";" */ +.Ve +.IP "\s-1EV_CB_DECLARE\s0(type)" 4 +.IX Item "EV_CB_DECLARE(type)" +.PD 0 +.IP "\s-1EV_CB_INVOKE\s0(watcher,revents)" 4 +.IX Item "EV_CB_INVOKE(watcher,revents)" +.IP "ev_set_cb(ev,cb)" 4 +.IX Item "ev_set_cb(ev,cb)" +.PD +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 \fIev.v\fR 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+. +.Sh "\s-1EXAMPLES\s0" +.IX Subsection "EXAMPLES" +For a real-world example of a program the includes libev +verbatim, you can have a look at the \s-1EV\s0 perl module +(<http://software.schmorp.de/pkg/EV.html>). It has the libev files in +the \fIlibev/\fR subdirectory and includes them in the \fI\s-1EV/EVAPI\s0.h\fR (public +interface) and \fI\s-1EV\s0.xs\fR (implementation) files. Only the \fI\s-1EV\s0.xs\fR file +will be compiled. It is pretty complex because it provides its own header +file. +.Sp +The usage in rxvt-unicode is simpler. It has a \fIev_cpp.h\fR header file +that everybody includes and which overrides some autoconf choices: +.Sp +.Vb 4 +\& #define EV_USE_POLL 0 +\& #define EV_MULTIPLICITY 0 +\& #define EV_PERIODICS 0 +\& #define EV_CONFIG_H <config.h> +.Ve +.Sp +.Vb 1 +\& #include "ev++.h" +.Ve +.Sp +And a \fIev_cpp.C\fR implementation file that contains libev proper and is compiled: +.Sp +.Vb 1 +\& #include "rxvttoolkit.h" +.Ve +.Sp +.Vb 2 +\& /* darwin has problems with its header files in C++, requiring this namespace juggling */ +\& using namespace ev; +.Ve +.Sp +.Vb 1 +\& #include "ev.c" +.Ve .SH "AUTHOR" .IX Header "AUTHOR" Marc Lehmann <libev@schmorp.de>. @@ -6,7 +6,7 @@ <meta name="description" content="Pod documentation for libev" /> <meta name="inputfile" content="<standard input>" /> <meta name="outputfile" content="<standard output>" /> - <meta name="created" content="Sat Nov 24 11:10:25 2007" /> + <meta name="created" content="Sat Nov 24 11:15:15 2007" /> <meta name="generator" content="Pod::Xhtml 1.57" /> <link rel="stylesheet" href="http://res.tst.eu/pod.css"/></head> <body> @@ -1672,24 +1672,17 @@ will be compiled. It is pretty complex because it provides its own header file.</p> <p>The usage in rxvt-unicode is simpler. It has a <cite>ev_cpp.h</cite> header file that everybody includes and which overrides some autoconf choices:</p> -<pre> #define EV_USE_POLL 0 - #define EV_MULTIPLICITY 0 - #define EV_PERIODICS 0 - #define EV_CONFIG_H <config.h> +<pre> #define EV_USE_POLL 0 + #define EV_MULTIPLICITY 0 + #define EV_PERIODICS 0 + #define EV_CONFIG_H <config.h> - #include "ev++.h" + #include "ev++.h" </pre> <p>And a <cite>ev_cpp.C</cite> implementation file that contains libev proper and is compiled:</p> -<pre> #include "rxvttoolkit.h" - - /* darwin has problems with its header files in C++, requiring this namespace juggling */ - using namespace ev; - - #include "ev.c" - - - +<pre> #include "ev_cpp.h" + #include "ev.c" </pre> |