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diff --git a/guide/ports.html b/guide/ports.html new file mode 100644 index 0000000..b09ea2a --- /dev/null +++ b/guide/ports.html @@ -0,0 +1,99 @@ +<!DOCTYPE html> +<html lang="en"> +<head> +<meta charset="utf-8"/> +<title>Erlang.mk User Guide</title> +<style type="text/css"><!-- +body{background:white;color:black;font-family:"Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;justify-content:center;margin:0 auto;padding:0;width:600px} +header {align-items:center;display:flex;justify-content:center} +header nav.left{text-align:right;width:150px} +header nav.right{text-align:left;width:150px} +header nav a{display:block;margin:1.5em 1em} +main{margin-top:2em;text-align:justify} +main h2, main h3{margin-top:2em} +a{color:#d9230f;text-decoration:none} +a:hover{text-decoration:underline} +h1, h2, h3{font-weight:normal} +div.navfooter{margin-bottom:1em} +--></style> +</head> +<body> +<header> + <nav class="left"> + <a href="index.html">User guide</a> + <a href="ch02.html">Tutorials</a> + </nav> + <a href="/" class="logo"><img src="../res/logo-small.png" alt="Erlang.mk" title="Erlang.mk: A build tool for Erlang that just works" height="200" width="206"/></a> + <nav class="right"> + <a href="https://github.com/ninenines/erlang.mk/tree/master/index">470+ packages</a> + <a href="https://github.com/ninenines/erlang.mk/issues">Issues?</a> + </nav> +</header> +<main> + +<div class="navheader"><table width="100%" summary="Navigation header"><tr><td width="20%" align="left"><a accesskey="p" href="deps.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="relx.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h2 class="title"><a id="ports"></a>Chapter 8. NIFs and port drivers</h2></div></div></div><p>Erlang.mk can not only build Erlang projects, but also the C code +that some projects come with, like NIFs and port drivers.</p><p>There are two ways to build the C code: using a custom Makefile, +or making Erlang.mk do it directly. The C code will be built +as needed when you run <code class="literal">make</code>.</p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="_c_source_code_location_and_erlang_environment"></a>8.1. C source code location and Erlang environment</h2></div></div></div><p>The C source code should be located in the <span class="emphasis"><em>$(C_SRC_DIR)</em></span> directory. +It defaults to <span class="emphasis"><em>c_src/</em></span>. Should you need to modify it, all you +need to do is to set the variable in your Makefile before including +Erlang.mk:</p><pre class="programlisting">C_SRC_DIR = $(CURDIR)/my_nif_source</pre><p>When this directory exists, Erlang.mk will automatically create a +file named <span class="emphasis"><em>$(C_SRC_ENV)</em></span>. This file defaults to <span class="emphasis"><em>$(C_SRC_DIR)/env.mk</em></span>. +This can also be changed:</p><pre class="programlisting">C_SRC_ENV = $(C_SRC_DIR)/erlang_env.mk</pre><p>It contains a few variable definitions for the environment used for the build:</p><div class="variablelist"><dl class="variablelist"><dt><span class="term"> +<code class="literal">ERTS_INCLUDE_DIR</code> +</span></dt><dd> + Path to the ERTS include files (<span class="emphasis"><em>erl_driver.h</em></span>, <span class="emphasis"><em>erl_nif.h</em></span> and more). +</dd><dt><span class="term"> +<code class="literal">ERL_INTERFACE_INCLUDE_DIR</code> +</span></dt><dd> + Path to the Erl_Interface include files (<span class="emphasis"><em>ei.h</em></span> and related). +</dd><dt><span class="term"> +<code class="literal">ERL_INTERFACE_LIB_DIR</code> +</span></dt><dd> + Path to the Erl_Interface static libraries. +</dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="_using_a_custom_makefile"></a>8.2. Using a custom Makefile</h2></div></div></div><p>Erlang.mk will automatically run <code class="literal">make</code> if it detects a Makefile +in <span class="emphasis"><em>$(C_SRC_DIR)/Makefile</em></span>.</p><p>The Makefile should have at least two targets: a default target +(which can be anything, for example <code class="literal">all</code>) which is invoked when +building the C code, and a <code class="literal">clean</code> target invoked when cleaning +it.</p><p>You can include the <span class="emphasis"><em>env.mk</em></span> file to benefit from the Erlang +environment detection:</p><pre class="programlisting">include env.mk</pre></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="_using_erlang_mk_directly"></a>8.3. Using Erlang.mk directly</h2></div></div></div><p>You don’t need to write a Makefile to build C source code, however. +Erlang.mk comes with rules to build both shared libraries and +executables, using the source files it finds in <span class="emphasis"><em>$(C_SRC_DIR)</em></span>.</p><p>By default, Erlang.mk will create a shared library. To change +this and create an executable instead, put this in your Makefile +before including Erlang.mk:</p><pre class="programlisting">C_SRC_TYPE = executable</pre><p>The generated file name varies depending on the type of project +you have (shared library or executable) and on the platform you +build the project on.</p><p>For shared libraries, the generated file name will be +<span class="emphasis"><em>$(C_SRC_OUTPUT)$(C_SRC_SHARED_EXTENSION)</em></span>, with the default +being <span class="emphasis"><em>$(CURDIR)/priv/$(PROJECT)</em></span> followed by the extension: +<code class="literal">.dll</code> on Windows, <code class="literal">.so</code> everywhere else.</p><p>For executables, the generated file name is +<span class="emphasis"><em>$(C_SRC_OUTPUT)$(C_SRC_EXECUTABLE_EXTENSION)</em></span>, with the same +default except for the extension: <code class="literal">.exe</code> on Windows, and otherwise +nothing.</p><p>Erlang.mk sets appropriate compile and linker flags by default. +These flags vary depending on the platform, and can of course +be overriden.</p><div class="variablelist"><dl class="variablelist"><dt><span class="term"> +<code class="literal">CC</code> +</span></dt><dd> + The compiler to be used. +</dd><dt><span class="term"> +<code class="literal">CFLAGS</code> +</span></dt><dd> + C compiler flags. +</dd><dt><span class="term"> +<code class="literal">CXXFLAGS</code> +</span></dt><dd> + C++ compiler flags. +</dd><dt><span class="term"> +<code class="literal">LDFLAGS</code> +</span></dt><dd> + Linker flags. +</dd><dt><span class="term"> +<code class="literal">LDLIBS</code> +</span></dt><dd> + Libraries to link against. +</dd></dl></div><p>The source files are automatically gathered from the contents +of <span class="emphasis"><em>$(C_SRC_DIR)</em></span>. Erlang.mk looks for <span class="emphasis"><em>.c</em></span>, <span class="emphasis"><em>.C</em></span>, <span class="emphasis"><em>.cc</em></span> and <span class="emphasis"><em>.cpp</em></span> +source files. You can define the variable <code class="literal">SOURCES</code> to manually +list the files to compile.</p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="deps.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="code.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="relx.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> </td></tr></table></div> +</main> +</body> +</html> |