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diff --git a/doc/src/sgml/html/extend-pgxs.html b/doc/src/sgml/html/extend-pgxs.html new file mode 100644 index 0000000..e196ad8 --- /dev/null +++ b/doc/src/sgml/html/extend-pgxs.html @@ -0,0 +1,230 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>38.18. Extension Building Infrastructure</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="extend-extensions.html" title="38.17. Packaging Related Objects into an Extension" /><link rel="next" href="triggers.html" title="Chapter 39. Triggers" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">38.18. Extension Building Infrastructure</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="extend-extensions.html" title="38.17. Packaging Related Objects into an Extension">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="extend.html" title="Chapter 38. Extending SQL">Up</a></td><th width="60%" align="center">Chapter 38. Extending <acronym class="acronym">SQL</acronym></th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="triggers.html" title="Chapter 39. Triggers">Next</a></td></tr></table><hr /></div><div class="sect1" id="EXTEND-PGXS"><div class="titlepage"><div><div><h2 class="title" style="clear: both">38.18. Extension Building Infrastructure</h2></div></div></div><a id="id-1.8.3.21.2" class="indexterm"></a><p> + If you are thinking about distributing your + <span class="productname">PostgreSQL</span> extension modules, setting up a + portable build system for them can be fairly difficult. Therefore + the <span class="productname">PostgreSQL</span> installation provides a build + infrastructure for extensions, called <acronym class="acronym">PGXS</acronym>, so + that simple extension modules can be built simply against an + already installed server. <acronym class="acronym">PGXS</acronym> is mainly intended + for extensions that include C code, although it can be used for + pure-SQL extensions too. Note that <acronym class="acronym">PGXS</acronym> is not + intended to be a universal build system framework that can be used + to build any software interfacing to <span class="productname">PostgreSQL</span>; + it simply automates common build rules for simple server extension + modules. For more complicated packages, you might need to write your + own build system. + </p><p> + To use the <acronym class="acronym">PGXS</acronym> infrastructure for your extension, + you must write a simple makefile. + In the makefile, you need to set some variables + and include the global <acronym class="acronym">PGXS</acronym> makefile. + Here is an example that builds an extension module named + <code class="literal">isbn_issn</code>, consisting of a shared library containing + some C code, an extension control file, an SQL script, an include file + (only needed if other modules might need to access the extension functions + without going via SQL), and a documentation text file: +</p><pre class="programlisting"> +MODULES = isbn_issn +EXTENSION = isbn_issn +DATA = isbn_issn--1.0.sql +DOCS = README.isbn_issn +HEADERS_isbn_issn = isbn_issn.h + +PG_CONFIG = pg_config +PGXS := $(shell $(PG_CONFIG) --pgxs) +include $(PGXS) +</pre><p> + The last three lines should always be the same. Earlier in the + file, you assign variables or add custom + <span class="application">make</span> rules. + </p><p> + Set one of these three variables to specify what is built: + + </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="varname">MODULES</code></span></dt><dd><p> + list of shared-library objects to be built from source files with same + stem (do not include library suffixes in this list) + </p></dd><dt><span class="term"><code class="varname">MODULE_big</code></span></dt><dd><p> + a shared library to build from multiple source files + (list object files in <code class="varname">OBJS</code>) + </p></dd><dt><span class="term"><code class="varname">PROGRAM</code></span></dt><dd><p> + an executable program to build + (list object files in <code class="varname">OBJS</code>) + </p></dd></dl></div><p> + + The following variables can also be set: + + </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="varname">EXTENSION</code></span></dt><dd><p> + extension name(s); for each name you must provide an + <code class="literal"><em class="replaceable"><code>extension</code></em>.control</code> file, + which will be installed into + <code class="literal"><em class="replaceable"><code>prefix</code></em>/share/extension</code> + </p></dd><dt><span class="term"><code class="varname">MODULEDIR</code></span></dt><dd><p> + subdirectory of <code class="literal"><em class="replaceable"><code>prefix</code></em>/share</code> + into which DATA and DOCS files should be installed + (if not set, default is <code class="literal">extension</code> if + <code class="varname">EXTENSION</code> is set, + or <code class="literal">contrib</code> if not) + </p></dd><dt><span class="term"><code class="varname">DATA</code></span></dt><dd><p> + random files to install into <code class="literal"><em class="replaceable"><code>prefix</code></em>/share/$MODULEDIR</code> + </p></dd><dt><span class="term"><code class="varname">DATA_built</code></span></dt><dd><p> + random files to install into + <code class="literal"><em class="replaceable"><code>prefix</code></em>/share/$MODULEDIR</code>, + which need to be built first + </p></dd><dt><span class="term"><code class="varname">DATA_TSEARCH</code></span></dt><dd><p> + random files to install under + <code class="literal"><em class="replaceable"><code>prefix</code></em>/share/tsearch_data</code> + </p></dd><dt><span class="term"><code class="varname">DOCS</code></span></dt><dd><p> + random files to install under + <code class="literal"><em class="replaceable"><code>prefix</code></em>/doc/$MODULEDIR</code> + </p></dd><dt><span class="term"><code class="varname">HEADERS</code><br /></span><span class="term"><code class="varname">HEADERS_built</code></span></dt><dd><p> + Files to (optionally build and) install under + <code class="literal"><em class="replaceable"><code>prefix</code></em>/include/server/$MODULEDIR/$MODULE_big</code>. + </p><p> + Unlike <code class="literal">DATA_built</code>, files in <code class="literal">HEADERS_built</code> + are not removed by the <code class="literal">clean</code> target; if you want them removed, + also add them to <code class="literal">EXTRA_CLEAN</code> or add your own rules to do it. + </p></dd><dt><span class="term"><code class="varname">HEADERS_$MODULE</code><br /></span><span class="term"><code class="varname">HEADERS_built_$MODULE</code></span></dt><dd><p> + Files to install (after building if specified) under + <code class="literal"><em class="replaceable"><code>prefix</code></em>/include/server/$MODULEDIR/$MODULE</code>, + where <code class="literal">$MODULE</code> must be a module name used + in <code class="literal">MODULES</code> or <code class="literal">MODULE_big</code>. + </p><p> + Unlike <code class="literal">DATA_built</code>, files in <code class="literal">HEADERS_built_$MODULE</code> + are not removed by the <code class="literal">clean</code> target; if you want them removed, + also add them to <code class="literal">EXTRA_CLEAN</code> or add your own rules to do it. + </p><p> + It is legal to use both variables for the same module, or any + combination, unless you have two module names in the + <code class="literal">MODULES</code> list that differ only by the presence of a + prefix <code class="literal">built_</code>, which would cause ambiguity. In + that (hopefully unlikely) case, you should use only the + <code class="literal">HEADERS_built_$MODULE</code> variables. + </p></dd><dt><span class="term"><code class="varname">SCRIPTS</code></span></dt><dd><p> + script files (not binaries) to install into + <code class="literal"><em class="replaceable"><code>prefix</code></em>/bin</code> + </p></dd><dt><span class="term"><code class="varname">SCRIPTS_built</code></span></dt><dd><p> + script files (not binaries) to install into + <code class="literal"><em class="replaceable"><code>prefix</code></em>/bin</code>, + which need to be built first + </p></dd><dt><span class="term"><code class="varname">REGRESS</code></span></dt><dd><p> + list of regression test cases (without suffix), see below + </p></dd><dt><span class="term"><code class="varname">REGRESS_OPTS</code></span></dt><dd><p> + additional switches to pass to <span class="application">pg_regress</span> + </p></dd><dt><span class="term"><code class="varname">ISOLATION</code></span></dt><dd><p> + list of isolation test cases, see below for more details + </p></dd><dt><span class="term"><code class="varname">ISOLATION_OPTS</code></span></dt><dd><p> + additional switches to pass to + <span class="application">pg_isolation_regress</span> + </p></dd><dt><span class="term"><code class="varname">TAP_TESTS</code></span></dt><dd><p> + switch defining if TAP tests need to be run, see below + </p></dd><dt><span class="term"><code class="varname">NO_INSTALL</code></span></dt><dd><p> + don't define an <code class="literal">install</code> target, useful for test + modules that don't need their build products to be installed + </p></dd><dt><span class="term"><code class="varname">NO_INSTALLCHECK</code></span></dt><dd><p> + don't define an <code class="literal">installcheck</code> target, useful e.g., if tests require special configuration, or don't use <span class="application">pg_regress</span> + </p></dd><dt><span class="term"><code class="varname">EXTRA_CLEAN</code></span></dt><dd><p> + extra files to remove in <code class="literal">make clean</code> + </p></dd><dt><span class="term"><code class="varname">PG_CPPFLAGS</code></span></dt><dd><p> + will be prepended to <code class="varname">CPPFLAGS</code> + </p></dd><dt><span class="term"><code class="varname">PG_CFLAGS</code></span></dt><dd><p> + will be appended to <code class="varname">CFLAGS</code> + </p></dd><dt><span class="term"><code class="varname">PG_CXXFLAGS</code></span></dt><dd><p> + will be appended to <code class="varname">CXXFLAGS</code> + </p></dd><dt><span class="term"><code class="varname">PG_LDFLAGS</code></span></dt><dd><p> + will be prepended to <code class="varname">LDFLAGS</code> + </p></dd><dt><span class="term"><code class="varname">PG_LIBS</code></span></dt><dd><p> + will be added to <code class="varname">PROGRAM</code> link line + </p></dd><dt><span class="term"><code class="varname">SHLIB_LINK</code></span></dt><dd><p> + will be added to <code class="varname">MODULE_big</code> link line + </p></dd><dt><span class="term"><code class="varname">PG_CONFIG</code></span></dt><dd><p> + path to <span class="application">pg_config</span> program for the + <span class="productname">PostgreSQL</span> installation to build against + (typically just <code class="literal">pg_config</code> to use the first one in your + <code class="varname">PATH</code>) + </p></dd></dl></div><p> + </p><p> + Put this makefile as <code class="literal">Makefile</code> in the directory + which holds your extension. Then you can do + <code class="literal">make</code> to compile, and then <code class="literal">make + install</code> to install your module. By default, the extension is + compiled and installed for the + <span class="productname">PostgreSQL</span> installation that + corresponds to the first <code class="command">pg_config</code> program + found in your <code class="varname">PATH</code>. You can use a different installation by + setting <code class="varname">PG_CONFIG</code> to point to its + <code class="command">pg_config</code> program, either within the makefile + or on the <code class="literal">make</code> command line. + </p><p> + You can also run <code class="literal">make</code> in a directory outside the source + tree of your extension, if you want to keep the build directory separate. + This procedure is also called a + <a id="id-1.8.3.21.7.2" class="indexterm"></a><em class="firstterm">VPATH</em> + build. Here's how: +</p><pre class="programlisting"> +mkdir build_dir +cd build_dir +make -f /path/to/extension/source/tree/Makefile +make -f /path/to/extension/source/tree/Makefile install +</pre><p> + </p><p> + Alternatively, you can set up a directory for a VPATH build in a similar + way to how it is done for the core code. One way to do this is using the + core script <code class="filename">config/prep_buildtree</code>. Once this has been done + you can build by setting the <code class="literal">make</code> variable + <code class="varname">VPATH</code> like this: +</p><pre class="programlisting"> +make VPATH=/path/to/extension/source/tree +make VPATH=/path/to/extension/source/tree install +</pre><p> + This procedure can work with a greater variety of directory layouts. + </p><p> + The scripts listed in the <code class="varname">REGRESS</code> variable are used for + regression testing of your module, which can be invoked by <code class="literal">make + installcheck</code> after doing <code class="literal">make install</code>. For this to + work you must have a running <span class="productname">PostgreSQL</span> server. + The script files listed in <code class="varname">REGRESS</code> must appear in a + subdirectory named <code class="literal">sql/</code> in your extension's directory. + These files must have extension <code class="literal">.sql</code>, which must not be + included in the <code class="varname">REGRESS</code> list in the makefile. For each + test there should also be a file containing the expected output in a + subdirectory named <code class="literal">expected/</code>, with the same stem and + extension <code class="literal">.out</code>. <code class="literal">make installcheck</code> + executes each test script with <span class="application">psql</span>, and compares the + resulting output to the matching expected file. Any differences will be + written to the file <code class="literal">regression.diffs</code> in <code class="command">diff + -c</code> format. Note that trying to run a test that is missing its + expected file will be reported as <span class="quote">“<span class="quote">trouble</span>”</span>, so make sure you + have all expected files. + </p><p> + The scripts listed in the <code class="varname">ISOLATION</code> variable are used + for tests stressing behavior of concurrent session with your module, which + can be invoked by <code class="literal">make installcheck</code> after doing + <code class="literal">make install</code>. For this to work you must have a + running <span class="productname">PostgreSQL</span> server. The script files + listed in <code class="varname">ISOLATION</code> must appear in a subdirectory + named <code class="literal">specs/</code> in your extension's directory. These files + must have extension <code class="literal">.spec</code>, which must not be included + in the <code class="varname">ISOLATION</code> list in the makefile. For each test + there should also be a file containing the expected output in a + subdirectory named <code class="literal">expected/</code>, with the same stem and + extension <code class="literal">.out</code>. <code class="literal">make installcheck</code> + executes each test script, and compares the resulting output to the + matching expected file. Any differences will be written to the file + <code class="literal">output_iso/regression.diffs</code> in + <code class="command">diff -c</code> format. Note that trying to run a test that is + missing its expected file will be reported as <span class="quote">“<span class="quote">trouble</span>”</span>, so + make sure you have all expected files. + </p><p> + <code class="literal">TAP_TESTS</code> enables the use of TAP tests. Data from each + run is present in a subdirectory named <code class="literal">tmp_check/</code>. + See also <a class="xref" href="regress-tap.html" title="33.4. TAP Tests">Section 33.4</a> for more details. + </p><div class="tip"><h3 class="title">Tip</h3><p> + The easiest way to create the expected files is to create empty files, + then do a test run (which will of course report differences). Inspect + the actual result files found in the <code class="literal">results/</code> + directory (for tests in <code class="literal">REGRESS</code>), or + <code class="literal">output_iso/results/</code> directory (for tests in + <code class="literal">ISOLATION</code>), then copy them to + <code class="literal">expected/</code> if they match what you expect from the test. + </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="extend-extensions.html" title="38.17. Packaging Related Objects into an Extension">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="extend.html" title="Chapter 38. 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