-<book>
-
- <bookinfo>
- <title>&uffi; Reference Guide</title>
- <author>
- <firstname>Kevin</firstname>
- <othername>M.</othername>
- <surname>Rosenberg</surname>
- <affiliation>
- <orgname>Heart Hospital of New Mexico</orgname>
- <address>
- <email>kevin@rosenberg.net</email>
- <street>504 Elm Street N.E.</street>
- <city>Albuquerque</city>
- <state>New Mexico</state>
- <postcode>87102</postcode>
- </address>
- </affiliation>
- </author>
-
- <printhistory>
- <simpara>$Id: bookinfo.sgml 7990 2003-10-12 21:26:56Z kevin $</simpara>
- <simpara>File $Date: 2003-10-12 15:26:56 -0600 (Sun, 12 Oct 2003) $</simpara>
- </printhistory>
- <copyright>
- <year>2002-2003</year>
- <holder>Kevin M. Rosenberg</holder>
- </copyright>
- <legalnotice>
- <itemizedlist>
- <listitem>
- <para>The &uffi; package was designed and
- written by Kevin M. Rosenberg.
- </para>
- </listitem>
-<listitem>
-<para>
- Permission is granted to copy, distribute and/or modify this document
- under the terms of the GNU Free Documentation License, Version 1.1
- or any later version published by the Free Software Foundation;
- with no Invariant Sections, with the no
- Front-Cover Texts, and with no Back-Cover Texts.
- A copy of the license is included in the &uffi; distribution.
-</para>
-</listitem>
- <listitem>
- <para><application>Allegro CL</application>® is a registered
- trademark of Franz Inc.
- </para>
- </listitem>
- <listitem>
- <para><application>Lispworks</application>® is a registered
- trademark of Xanalys Inc.
- </para>
- </listitem>
- <listitem>
- <para><application>Microsoft
- Windows</application>® is a registered trademark of
- Microsoft Inc.
- </para>
- </listitem>
- <listitem>
- <para>Other brand or
- product names are the registered trademarks or trademarks of
- their respective holders.
- </para>
- </listitem>
- </itemizedlist>
- </legalnotice>
- </bookinfo>
-
-<preface>
- <title>Preface</title>
- <para>This reference guide describes the usage and features
- of &uffi;. The first
- chapter provides an overview to the design of &uffi;.
- Following that chapter is the reference section for all user
- accessible functions of &uffi;. The appendix covers the
- installation and implementation-specifc features of &uffi;.
- </para>
-</preface>
-
-
-<chapter>
- <title>Introduction</title>
- <sect1>
- <title>Purpose</title>
- <para> This reference guide describes
- &uffi;, a package that provides a cross-implementation
- interface from Common Lisp to C-language compatible libraries.
- </para>
- </sect1>
-
- <sect1>
- <title>Background
- </title>
- <para>
- Every Common Lisp implementation has
- a method for interfacing to C-language compatible
- libraries. These methods are often termed a
- <emphasis>Foreign Function Library Interface</emphasis>
- (&ffi;). Unfortunately, these methods vary widely
- amongst
- implementations, thus preventing the writing of a portable FFI to a
-particular C-library.
- </para>
- <para>
- &uffi; gathers a common subset of functionality between Common Lisp
- implementations. &uffi; wraps this common subset of functionality with
- it's own syntax and provides macro translation of uffi functions into
- the specific syntax of supported Common Lisp implementations.
- </para>
- <para>
- Developers who use &uffi; to interface with C libraries will
- automatically have their code function in each of uffi's supported
- implementations.
- </para>
- </sect1>
-
- <sect1>
- <title>Supported Implementations</title>
- <para>The primary tested and supported platforms for &uffi; are:
- </para>
- <itemizedlist mark="opencircle">
- <listitem><para>&acl; v6.2 on Debian GNU/Linux
-FreeBSD 4.5, Solaris v2.8, and Microsoft Windows XP.</para></listitem>
- <listitem><para>&lw; v4.2 on Debian GNU/Linux and Microsoft Windows XP.</para></listitem>
- <listitem><para>&cmucl; 18d on Debian GNU/Linux, FreeBSD 4.5, and Solaris 2.8</para></listitem>
- <listitem><para>&sbcl; 0.7.8 on Debian GNU/Linux</para></listitem>
- <listitem><para>&scl; 1.1.1 on Debian GNU/Linux</para></listitem>
- <listitem><para>&openmcl; 0.13 on Debian GNU/Linux for PowerPC</para></listitem>
- </itemizedlist>
- <para>Beta code is included with &uffi; for
- </para>
- <itemizedlist mark="opencircle">
- <listitem><para>&openmcl; and &mcl; with MacOSX</para></listitem>
- </itemizedlist>
- </sect1>
-
- <sect1>
- <title>Design</title>
- <sect2>
- <title>Overview</title>
- <para>
- &uffi; was designed as a cross-implementation
- compatible <emphasis>Foreign Function Interface</emphasis>.
- Necessarily,
- only a common subset of functionality can be
- provided. Likewise, not every optimization for that a specific
- implementation provides can be supported. Wherever possible,
- though, implementation-specific optimizations are invoked.
- </para>
- </sect2>
-
- <sect2>
- <title>Priorities</title>
- <para>
- The design of &uffi; is dictated by the order of these priorities:
- </para>
- <itemizedlist>
- <listitem>
- <para>
- Code using &uffi; must operate correctly on all
- supported implementations.
- </para>
- </listitem>
- <listitem>
- <para>
- Take advantage of implementation-specific optimizations. Ideally,
- there will not a situation where an implementation-specific
- &ffi; will be chosen due to lack of optimizations in &uffi;.
- </para>
- </listitem>
- <listitem>
- <para>Provide a simple interface to developers using
-&uffi;. This priority is quite a bit lower than the above priorities.
-This lower priority is manifest by programmers having to pass types in
-pointer and array dereferencing, needing to use
-<constant>cstring</constant> wrapper functions, and the use of
-ensure-char-character and ensure-char-integer functions. My hope is
-that the developer inconvenience will be outweighed by the generation
-of optimized code that is cross-implementation compatible.
- </para>
- </listitem>
- </itemizedlist>
- </sect2>
- </sect1>
-
-</chapter>
-
-
-<chapter>
- <title>Programming Notes</title>
-
- <sect1>
- <title>Implementation Specific Notes</title>
- <para>
- </para>
- <sect2>
- <title>&acl;</title>
- <para>
- </para>
- </sect2>
- <sect2>
- <title>&lw;</title>
- <para>
- </para>
- </sect2>
- <sect2>
- <title>&cmucl;</title>
- <para>
- </para>
- </sect2>
- </sect1>
-
- <sect1>
- <title>Foreign Object Representation and Access</title>
- <para> There are two main approaches used to represent foreign
- objects: an integer that represents an address in memory, and a
- object that also includes run-time typing. The advantage of
- run-time typing is the system can dereference pointers and perform
- array access without those functions requiring a type at the cost
- of additional overhead to generate and store the run-time
- typing. The advantage of integer representation, at least for
- &acl;, is that the compiler can generate inline code to
- dereference pointers. Further, the overhead of the run-time type
- information is eliminated. The disadvantage is the program must
- then supply
- the type to the functions to dereference objects and array.
- </para>
- </sect1>
-
- <sect1>
- <title>Optimizing Code Using UFFI</title>
- <sect2>
- <title>Background</title>
- <para>
- Two implementions have different techniques to optimize
- (open-code) foreign objects. &acl; can open-code foreign
- object
- access if pointers are integers and the type of object is
- specified in the access function. Thus, &uffi; represents objects
- in &acl; as integers which don't have type information.
- </para> <para>
- &cmucl; works best when keeping objects as typed
- objects. However, it's compiler can open-code object access when
- the object type is specified in <function>declare</function>
- commands and in <varname>:type</varname> specifiers in
- <function>defstruct</function> and <function>defclass</function>.
- </para> <para> &lw;, in converse to &acl; and &cmucl; does not do
- any open coding of object access. &lw;, by default, maintains
- objects with run-time typing. </para>
- </sect2>
- <sect2>
- <title>Cross-Implementation Optimization</title>
- <para>
- To fully optimize across platforms, both explicit type
- information must be passed to dereferencing of pointers and
- arrays. Though this optimization only helps with &acl;, &uffi;
- is designed to require this type information be passed the
- dereference functions. Second, declarations of type should be
- made in functions, structures, and classes where foreign
- objects will be help. This will optimize access for &lw;
- </para>
- <para>
- Here is an example that should both methods being used for
- maximum cross-implementation optimization:
- <programlisting>
-(uffi:def-type the-struct-type-def the-struct-type)
-(let ((a-foreign-struct (allocate-foreign-object 'the-struct-type)))
- (declare 'the-struct-type-def a-foreign-struct)
- (get-slot-value a-foreign-struct 'the-struct-type 'field-name))
- </programlisting>
- </para>
- </sect2>
- </sect1>
-
-</chapter>
-
-
-<reference>
- <title>Declarations</title>
-
- <partintro>
- <sect1>
- <title>Overview</title>
- <para>Declarations are used to give the compiler optimizing
- information about foreign types. Currently, only &cmucl;
- supports declarations. On &acl; and &lw;, these expressions
- declare the type generically as &t;
- </para>
- </sect1>
- </partintro>
-
- <refentry id="def-type">
- <refnamediv>
- <refname>def-type</refname>
- <refpurpose>Defines a Common Lisp type.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>def-type</function> <replaceable>name type</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>name</parameter></term>
- <listitem>
- <para>A symbol naming the type</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>A form that is evaluated that specifies the &uffi; type.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>Defines a Common Lisp type based on a &uffi; type.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-type char-ptr '(* :char))
-...
-(defun foo (ptr)
- (declare (type char-ptr ptr))
- ...
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>Defines a new &cl; type.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
- </reference>
-
-
- <reference>
- <title>Primitive Types</title>
- <partintro>
- <title>Overview</title>
- <para>
- Primitive types have a single value, these include
- characters, numbers, and pointers. They are all symbols in
- the keyword package.
- </para>
- <itemizedlist>
- <listitem>
- <para><constant>:char</constant> - Signed 8-bits. A
-dereferenced :char pointer returns an character.</para>
- </listitem>
- <listitem>
- <para><constant>:unsigned-char</constant> - Unsigned 8-bits. A dereferenced :unsigned-char
-pointer returns an character.</para>
- </listitem>
- <listitem>
- <para><constant>:byte</constant> - Signed 8-bits. A
-dereferenced :byte pointer returns an integer.</para>
- </listitem>
- <listitem>
- <para><constant>:unsigned-byte</constant> - Unsigned 8-bits. A
-dereferenced :unsigned-byte pointer returns an integer.</para>
- </listitem>
- <listitem>
- <para><constant>:short</constant> - Signed 16-bits.</para>
- </listitem>
- <listitem>
- <para><constant>:unsigned-short</constant> - Unsigned 16-bits.</para>
- </listitem>
- <listitem>
- <para><constant>:int</constant> - Signed 32-bits.</para>
- </listitem>
- <listitem>
- <para><constant>:unsigned-int</constant> - Unsigned 32-bits.</para>
- </listitem>
- <listitem>
- <para><constant>:long</constant> - Signed 32 or 64 bits, depending upon the platform.</para>
- </listitem>
- <listitem>
- <para><constant>:unsigned-long</constant> - Unsigned 32 or 64 bits, depending upon the platform.</para>
- </listitem>
- <listitem>
- <para><constant>:float</constant> - 32-bit floating point.</para>
- </listitem>
- <listitem>
- <para><constant>:double</constant> - 64-bit floating point.</para>
- </listitem>
- <listitem>
- <para><constant>:cstring</constant> -
-A &null; terminated string used for passing and returning characters strings with a &c; function.
- </para>
- </listitem>
- <listitem>
- <para><constant>:void</constant> -
-The absence of a value. Used to indicate that a function does not return a value.</para>
- </listitem>
- <listitem>
- <para><constant>:pointer-void</constant> -
-Points to a generic object.</para>
- </listitem>
- <listitem>
- <para><constant>*</constant> - Used to declare a pointer to an object</para>
- </listitem>
- </itemizedlist>
- </partintro>
-
- <refentry id="def-constant">
- <refnamediv>
- <refname>def-constant</refname>
- <refpurpose>Binds a symbol to a constant.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>def-constant</function> <replaceable>name value &key export</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>name</parameter></term>
- <listitem>
- <para>A symbol that will be bound to the value.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>value</parameter></term>
- <listitem>
- <para>An evaluated form that is bound the the name.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>export</parameter></term>
- <listitem>
- <para>When &t;, the name is exported from the current package. The default is &nil;</para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- This is a thin wrapper around
- <function>defconstant</function>. It evaluates at
- compile-time and optionally exports the symbol from the package.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-constant pi2 (* 2 pi))
-(def-constant exported-pi2 (* 2 pi) :export t)
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>Creates a new special variable..</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="def-foreign-type">
- <refnamediv>
- <refname>def-foreign-type</refname>
- <refpurpose>Defines a new foreign type.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsect1>
- <title>Syntax</title>
-<synopsis>
- <function>def-foreign-type</function> <replaceable>name type</replaceable>
-</synopsis>
- </refsect1>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>name</parameter></term>
- <listitem>
- <para>A symbol naming the new foreign type.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>value</parameter></term>
- <listitem>
- <para>A form that is not evaluated that defines the new
-foreign type.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>Defines a new foreign type.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-foreign-type my-generic-pointer :pointer-void)
-(def-foreign-type a-double-float :double-float)
-(def-foreign-type char-ptr (* :char))
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>Defines a new foreign type.
- </para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="null-char-p">
- <refnamediv>
- <refname>null-char-p</refname>
- <refpurpose>Tests a character for &null; value.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsect1>
- <title>Syntax</title>
-<synopsis>
- <function>null-char-p</function> <replaceable>char</replaceable> => <returnvalue>is-null</returnvalue>
-</synopsis>
- </refsect1>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>char</parameter></term>
- <listitem>
- <para>A character or integer.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>is-null</parameter></term>
- <listitem>
- <para>A boolean flag indicating if char is a &null; value.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- A predicate testing if a character or integer is &null;. This
-abstracts the difference in implementations where some return a
-<computeroutput>character</computeroutput> and some return a
-<computeroutput>integer</computeroutput> whence dereferencing a
-<computeroutput>C</computeroutput> character pointer.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-array-pointer ca :unsigned-char)
-(let ((fs (convert-to-foreign-string "ab")))
- (values (null-char-p (deref-array fs 'ca 0))
- (null-char-p (deref-array fs 'ca 2))))
-=> &nil;
- &t;
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.
- </para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
- </reference>
-
- <reference>
- <title>Aggregate Types</title>
- <partintro>
- <title>Overview</title>
- <para>
- Aggregate types are comprised of one or more primitive types.
- </para>
- </partintro>
-
- <refentry id="def-enum">
- <refnamediv>
- <refname>def-enum</refname>
- <refpurpose>Defines a &c; enumeration.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>def-enum</function> <replaceable>name fields &key separator-string</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>name</parameter></term>
- <listitem>
- <para>A symbol that names the enumeration.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>fields</parameter></term>
- <listitem>
- <para>A list of field defintions. Each definition can be
-a symbol or a list of two elements. Symbols get assigned a value of the
-current counter which starts at <computeroutput>0</computeroutput> and
-increments by <computeroutput>1</computeroutput> for each subsequent symbol. It the field definition is a list, the first position is the symbol and the second
-position is the value to assign the the symbol. The current counter gets set
-to <computeroutput>1+</computeroutput> this value.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>separator-string</parameter></term>
- <listitem>
- <para>A string that governs the creation of constants. The
-default is <computeroutput>"#"</computeroutput>.</para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Declares a &c; enumeration. It generates constants with integer values for the elements of the enumeration. The symbols for the these constant
-values are created by the <function>concatenation</function> of the
-enumeration name, separator-string, and field symbol. Also creates
-a foreign type with the name <parameter>name</parameter> of type
-<constant>:int</constant>.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-enum abc (:a :b :c))
-;; Creates constants abc#a (1), abc#b (2), abc#c (3) and defines
-;; the foreign type "abc" to be :int
-
-(def-enum efoo (:e1 (:e2 10) :e3) :separator-string "-")
-;; Creates constants efoo-e1 (1), efoo-e2 (10), efoo-e3 (11) and defines
-;; the foreign type efoo to be :int
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>Creates a :int foreign type, defines constants.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="def-struct">
- <refnamediv>
- <refname>def-struct</refname>
- <refpurpose>Defines a &c; structure.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>def-struct</function> <replaceable>name &rest fields</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>name</parameter></term>
- <listitem>
- <para>A symbol that names the structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>fields</parameter></term>
- <listitem>
- <para>A variable number of field defintions. Each definition is a list consisting of a symbol naming the field followed by its foreign type.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Declares a structure. A special type is available as a slot
-in the field. It is a pointer that points to an instance of the parent
-structure. It's type is <constant>:pointer-self</constant>.
-
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-struct foo (a :unsigned-int)
- (b (* :char))
- (c (:array :int 10))
- (next :pointer-self))
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>Creates a foreign type.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="get-slot-value">
- <refnamediv>
- <refname>get-slot-value</refname>
- <refpurpose>Retrieves a value from a slot of a structure.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>get-slot-value</function> <replaceable>obj type field</replaceable> => <returnvalue>value</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>obj</parameter></term>
- <listitem>
- <para>A pointer to foreign structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>A name of the foreign structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>field</parameter></term>
- <listitem>
- <para>A name of the desired field in foreign structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>value</returnvalue></term>
- <listitem>
- <para>The value of the field in the structure.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Accesses a slot value from a structure.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(get-slot-value foo-ptr 'foo-structure 'field-name)
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="get-slot-pointer">
- <refnamediv>
- <refname>get-slot-pointer</refname>
- <refpurpose>Retrieves a pointer from a slot of a structure.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>get-slot-pointer</function> <replaceable>obj type field</replaceable> => <returnvalue>pointer</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>obj</parameter></term>
- <listitem>
- <para>A pointer to foreign structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>A name of the foreign structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>field</parameter></term>
- <listitem>
- <para>A name of the desired field in foreign structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>pointer</returnvalue></term>
- <listitem>
- <para>The value of the field in the structure.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- This is similar to <function>get-slot-value</function>. It
- is used when the value of a slot is a pointer type.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(get-slot-pointer foo-ptr 'foo-structure 'my-char-ptr)
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="def-array-pointer">
- <refnamediv>
- <refname>def-array-pointer</refname>
- <refpurpose>Defines a pointer to a array of type.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>def-array-pointer</function> <replaceable>name type</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>name</parameter></term>
- <listitem>
- <para>A name of the new foreign type.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>The foreign type of the array elements.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Defines a type tat is a pointer to an array of type.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-array-pointer byte-array-pointer :unsigned-char)
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>Defines a new foreign type.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="deref-array">
- <refnamediv>
- <refname>deref-array</refname>
- <refpurpose>Deference an array.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>deref-array</function> <replaceable>array type positon</replaceable> => <returnvalue>value</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>array</parameter></term>
- <listitem>
- <para>A foreign array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>The foreign type of the array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>position</parameter></term>
- <listitem>
- <para>An integer specifying the position to retrieve from
-the array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>value</returnvalue></term>
- <listitem>
- <para>The value stored in the position of the array.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Dereferences (retrieves) the value of an array element.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-array-pointer ca :char)
-(let ((fs (convert-to-foreign-string "ab")))
- (values (null-char-p (deref-array fs 'ca 0))
- (null-char-p (deref-array fs 'ca 2))))
-=> &nil;
- &t;
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Notes</title>
- <para>
- The TYPE argument is ignored for CL implementations other than
- AllegroCL. If you want to cast a pointer to another type use
- WITH-CAST-POINTER together with DEREF-POINTER/DEREF-ARRAY.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="def-union">
- <refnamediv>
- <refname>def-union</refname>
- <refpurpose>Defines a foreign union type.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>def-union</function> <replaceable>name &rest fields</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>name</parameter></term>
- <listitem>
- <para>A name of the new union type.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>fields</parameter></term>
- <listitem>
- <para>A list of fields of the union.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Defines a foreign union type.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-union test-union
- (a-char :char)
- (an-int :int))
-
-(let ((u (allocate-foreign-object 'test-union))
- (setf (get-slot-value u 'test-union 'an-int) (+ 65 (* 66 256)))
- (prog1
- (ensure-char-character (get-slot-value u 'test-union 'a-char))
- (free-foreign-object u)))
-=> #\A
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>Defines a new foreign type.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
-</reference>
-
-<reference>
- <title>Objects</title>
-<partintro>
-<title>Overview</title>
- <para>
- Objects are entities that can allocated, referred to by pointers, and
-can be freed.
- </para>
-</partintro>
-
-
- <refentry id="allocate-foreign-object">
- <refnamediv>
- <refname>allocate-foreign-object</refname>
- <refpurpose>Allocates an instance of a foreign object.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>allocate-foreign-object</function> <replaceable>type &optional size</replaceable> => <returnvalue>ptr</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>The type of foreign object to allocate. This parameter is evaluated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>size</parameter></term>
- <listitem>
- <para>An optional size parameter that is evaluated. If specified, allocates and returns an
-array of <parameter>type</parameter> that is <parameter>size</parameter> members long. This parameter is evaluated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>ptr</returnvalue></term>
- <listitem>
- <para>A pointer to the foreign object.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Allocates an instance of a foreign object. It returns a pointer to the object.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-struct ab (a :int) (b :double))
-(allocate-foreign-object 'ab)
-=> #<ptr>
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="free-foreign-object">
- <refnamediv>
- <refname>free-foreign-object</refname>
- <refpurpose>Frees memory that was allocated for a foreign boject.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>free-foreign-object</function> <replaceable>ptr</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>ptr</parameter></term>
- <listitem>
- <para>A pointer to the allocated foreign object to free.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Frees the memory used by the allocation of a foreign object.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="with-foreign-object">
- <refnamediv>
- <refname>with-foreign-object</refname>
- <refpurpose>Wraps the allocation of a foreign object around a body of code.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>with-foreign-object</function> <replaceable>(var type) &body body</replaceable> => <returnvalue>form-return</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>var</parameter></term>
- <listitem>
- <para>The variable name to bind.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>The type of foreign object to allocate. This parameter is evaluated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>form-return</returnvalue></term>
- <listitem>
- <para>The result of evaluating the <parameter>body</parameter>.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
-This function wraps the allocation, binding, and destruction of a foreign object.
-On &cmucl; and
-&lw; platforms the object is stack allocated for efficiency. Benchmarks show that &acl; performs
-much better with static allocation.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(defun gethostname2 ()
- "Returns the hostname"
- (uffi:with-foreign-object (name '(:array :unsigned-char 256))
- (if (zerop (c-gethostname (uffi:char-array-to-pointer name) 256))
- (uffi:convert-from-foreign-string name)
- (error "gethostname() failed."))))
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="size-of-foreign-type">
- <refnamediv>
- <refname>size-of-foreign-type</refname>
- <refpurpose>Returns the number of data bytes used by a foreign object type.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>size-of-foreign-type</function> <replaceable>ftype</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>ftype</parameter></term>
- <listitem>
- <para>A foreign type specifier. This parameter is evaluated.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Returns the number of data bytes used by a foreign object type. This does not include any Lisp storage overhead.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <para>
-<programlisting>
-(size-of-foreign-object :unsigned-byte)
-=> 1
-(size-of-foreign-object 'my-100-byte-vector-type)
-=> 100
-</programlisting>
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1> <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="pointer-address">
- <refnamediv>
- <refname>pointer-address</refname>
- <refpurpose>Returns the address of a pointer.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>pointer-address</function> <replaceable>ptr</replaceable> => <returnvalue>address</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>ptr</parameter></term>
- <listitem>
- <para>A pointer to a foreign object.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>address</parameter></term>
- <listitem>
- <para>An integer representing the pointer's address.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Returns the address as an integer of a pointer.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="deref-pointer">
- <refnamediv>
- <refname>deref-pointer</refname>
- <refpurpose>Deferences a pointer.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>deref-pointer</function> <replaceable>ptr type</replaceable> => <returnvalue>value</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>ptr</parameter></term>
- <listitem>
- <para>A pointer to a foreign object.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>A foreign type of the object being pointed to.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>value</returnvalue></term>
- <listitem>
- <para>The value of the object where the pointer points.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Returns the object to which a pointer points.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <para>
-<programlisting>
-(let ((intp (allocate-foreign-object :int)))
- (setf (deref-pointer intp :int) 10)
- (prog1
- (deref-pointer intp :int)
- (free-foreign-object intp)))
-=> 10
-</programlisting>
- </para>
- </refsect1>
- <refsect1>
- <title>Notes</title>
- <para>
- The TYPE argument is ignored for CL implementations other than
- AllegroCL. If you want to cast a pointer to another type use
- WITH-CAST-POINTER together with DEREF-POINTER/DEREF-ARRAY.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="ensure-char-character">
- <refnamediv>
- <refname>ensure-char-character</refname>
- <refpurpose>Ensures that a dereferenced <constant>:char</constant> pointer is
-a character.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>ensure-char-character</function> <replaceable>object</replaceable> => <returnvalue>char</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>object</parameter></term>
- <listitem>
- <para>Either a character or a integer specifying a character code.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>char</returnvalue></term>
- <listitem>
- <para>A character.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Ensures that an objects obtained by dereferencing
-<constant>:char</constant> and <constant>:unsigned-char</constant>
-pointers are a lisp character.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <para>
-<programlisting>
-(let ((fs (convert-to-foreign-string "a")))
- (prog1
- (ensure-char-character (deref-pointer fs :char))
- (free-foreign-object fs)))
-=> #\a
-</programlisting>
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>Depending upon the implementation and what &uffi; expects, this
-macro may signal an error if the object is not a character or
-integer.</para>
- </refsect1>
- </refentry>
-
- <refentry id="ensure-char-integer">
- <refnamediv>
- <refname>ensure-char-integer</refname>
- <refpurpose>Ensures that a dereferenced <constant>:char</constant> pointer is
-an integer.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>ensure-char-integer</function> <replaceable>object</replaceable> => <returnvalue>int</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>object</parameter></term>
- <listitem>
- <para>Either a character or a integer specifying a character code.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>int</returnvalue></term>
- <listitem>
- <para>An integer.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Ensures that an object obtained by dereferencing a
-<constant>:char</constant> pointer is an integer.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <para>
-<programlisting>
-(let ((fs (convert-to-foreign-string "a")))
- (prog1
- (ensure-char-integer (deref-pointer fs :char))
- (free-foreign-object fs)))
-=> 96
-</programlisting>
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>Depending upon the implementation and what &uffi; expects, this
-macro may signal an error if the object is not a character or
-integer.</para>
- </refsect1>
- </refentry>
-
- <refentry id="make-null-pointer">
- <refnamediv>
- <refname>make-null-pointer</refname>
- <refpurpose>Create a &null; pointer.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>make-null-pointer</function> <replaceable>type</replaceable> => <returnvalue>ptr</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>A type of object to which the pointer refers.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>ptr</parameter></term>
- <listitem>
- <para>The &null; pointer of type <parameter>type</parameter>.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Creates a &null; pointer of a specified type.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="null-pointer-p">
- <refnamediv>
- <refname>null-pointer-p</refname>
- <refpurpose>Tests a pointer for &null; value.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>null-pointer-p</function> <replaceable>ptr</replaceable> => <returnvalue>is-null</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>ptr</parameter></term>
- <listitem>
- <para>A foreign object pointer.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>is-null</returnvalue></term>
- <listitem>
- <para>The boolean flag.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- A predicate testing if a pointer is has a &null; value.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="null-cstring-pointer">
- <refnamediv>
- <refname>+null-cstring-pointer+</refname>
- <refpurpose>A constant &null; cstring pointer.
- </refpurpose>
- <refclass>Constant</refclass>
- </refnamediv>
- <refsect1>
- <title>Description</title>
- <para>
- A &null; cstring pointer. This can be used for testing
-if a cstring returned by a function is &null;.
- </para>
- </refsect1>
- </refentry>
-
- <refentry id="with-cast-pointer">
- <refnamediv>
- <refname>with-cast-pointer</refname>
- <refpurpose>Wraps a body of code with a pointer cast to a new type.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>with-cast-pointer</function> (<replaceable>binding-name ptr type) & body body</replaceable> => <returnvalue>value</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>ptr</parameter></term>
- <listitem>
- <para>A pointer to a foreign object.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>A foreign type of the object being pointed to.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>value</returnvalue></term>
- <listitem>
- <para>The value of the object where the pointer points.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Executes BODY with POINTER cast to be a pointer to type TYPE. If
- BINDING-NAME is provided the cast pointer will be bound to this
- name during the execution of BODY. If BINDING-NAME is not provided
- POINTER must be a name bound to the pointer which should be
- cast. This name will be bound to the cast pointer during the
- execution of BODY.
-
- This is a no-op in AllegroCL but will wrap BODY in a LET form if
- BINDING-NAME is provided.
-
- This macro is meant to be used in conjunction with DEREF-POINTER or
- DEREF-ARRAY. In Allegro CL the "cast" will actually take place in
- DEREF-POINTER or DEREF-ARRAY.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
-<programlisting>
-(with-foreign-object (size :int)
- ;; FOO is a foreign function returning a :POINTER-VOID
- (let ((memory (foo size)))
- (when (mumble)
- ;; at this point we know for some reason that MEMORY points
- ;; to an array of unsigned bytes
- (with-cast-pointer (memory :unsigned-byte)
- (dotimes (i (deref-pointer size :int))
- (do-something-with
- (deref-array memory '(:array :unsigned-byte) i)))))))
-</programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="def-foreign-var">
- <refnamediv>
- <refname>def-foreign-var</refname>
- <refpurpose>
-Defines a symbol macro to access a variable in foreign code
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>def-foreign-var</function> <replaceable>name type module</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>name</parameter></term>
- <listitem>
- <para>
-A string or list specificying the symbol macro's name. If it is a
- string, that names the foreign variable. A Lisp name is created
- by translating #\_ to #\- and by converting to upper-case in
- case-insensitive Lisp implementations. If it is a list, the first
- item is a string specifying the foreign variable name and the
- second it is a symbol stating the Lisp name.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>type</parameter></term>
- <listitem>
- <para>A foreign type of the foreign variable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>module</returnvalue></term>
- <listitem>
- <para>
- A string specifying the module (or library) the foreign variable
- resides in. (Required by Lispworks)
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
-Defines a symbol macro which can be used to access (get and set) the
-value of a variable in foreign code.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <refsect2>
- <title>C code</title>
-<programlisting>
- int baz = 3;
-
- typedef struct {
- int x;
- double y;
- } foo_struct;
-
- foo_struct the_struct = { 42, 3.2 };
-
- int foo () {
- return baz;
- }
-</programlisting>
-</refsect2>
-<refsect2>
-<title>Lisp code</title>
-<programlisting>
- (uffi:def-struct foo-struct
- (x :int)
- (y :double))
-
- (uffi:def-function ("foo" foo)
- ()
- :returning :int
- :module "foo")
-
- (uffi:def-foreign-var ("baz" *baz*) :int "foo")
- (uffi:def-foreign-var ("the_struct" *the-struct*) foo-struct "foo")
-
-
-*baz*
- => 3
-
-(incf *baz*)
- => 4
-
-(foo)
- => 4
-</programlisting>
-</refsect2>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-</reference>
-
- <reference>
- <title>Strings</title>
-<partintro>
-<title>Overview</title>
-<para>
-
- &uffi; has functions to two types of
-<varname>C</varname>-compatible
- strings: <emphasis>cstring</emphasis> and
-<emphasis>foreign</emphasis> strings.
-
-cstrings are used <emphasis>only</emphasis> as parameters to and from
-functions. In some implementations a cstring is not a foreign type but
-rather the Lisp string itself. On other platforms a cstring is a newly
-allocated foreign vector for storing characters. The following is an
-example of using cstrings to both send and return a value.
-</para>
-
-<programlisting>
-(uffi:def-function ("getenv" c-getenv)
- ((name :cstring))
- :returning :cstring)
-
-(defun my-getenv (key)
- "Returns an environment variable, or NIL if it does not exist"
- (check-type key string)
- (uffi:with-cstring (key-native key)
- (uffi:convert-from-cstring (c-getenv key-native))))
-</programlisting>
-
-<para> In contrast, foreign strings are always a foreign vector of
-characters which have memory allocated. Thus, if you need to allocate
-memory to hold the return value of a string, you must use a foreign
-string and not a cstring. The following is an example of using a foreign
-string for a return value. </para>
-
-<programlisting>
-(uffi:def-function ("gethostname" c-gethostname)
- ((name (* :unsigned-char))
- (len :int))
- :returning :int)
-
-(defun gethostname ()
- "Returns the hostname"
- (let* ((name (uffi:allocate-foreign-string 256))
- (result-code (c-gethostname name 256))
- (hostname (when (zerop result-code)
- (uffi:convert-from-foreign-string name))))
- (uffi:free-foreign-object name)
- (unless (zerop result-code)
- (error "gethostname() failed."))))
-</programlisting>
-
-<para> Foreign functions that return pointers to freshly allocated
-strings should in general not return cstrings, but foreign strings.
-(There is no portable way to release such cstrings from Lisp.) The
-following is an example of handling such a function. </para>
-
-<programlisting>
-(uffi:def-function ("readline" c-readline)
- ((prompt :cstring))
- :returning (* :char))
-
-(defun readline (prompt)
- "Reads a string from console with line-editing."
- (with-cstring (c-prompt prompt)
- (let* ((c-str (c-readline c-prompt))
- (str (convert-from-foreign-string c-str)))
- (uffi:free-foreign-object c-str)
- str)))
-</programlisting>
-
-</partintro>
-
- <refentry id="convert-from-cstring">
- <refnamediv>
- <refname>convert-from-cstring</refname>
- <refpurpose>Converts a cstring to a Lisp string.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>convert-from-cstring</function> <replaceable>cstring</replaceable> => <returnvalue>string</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>cstring</parameter></term>
- <listitem>
- <para>A cstring.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>string</returnvalue></term>
- <listitem>
- <para>A Lisp string.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Converts a Lisp string to a <constant>cstring</constant>. This is
-most often used when processing the results of a foreign function
-that returns a cstring.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="convert-to-cstring">
- <refnamediv>
- <refname>convert-to-cstring</refname>
- <refpurpose>Converts a Lisp string to a cstring.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>convert-to-cstring</function> <replaceable>string</replaceable> => <returnvalue>cstring</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>string</parameter></term>
- <listitem>
- <para>A Lisp string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>cstring</returnvalue></term>
- <listitem>
- <para>A cstring.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Converts a Lisp string to a
- <varname>cstring</varname>. The
- <varname>cstring</varname> should be freed with
- <function>free-cstring</function>.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>On some implementations, this function allocates memory.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="free-cstring">
- <refnamediv>
- <refname>free-cstring</refname>
- <refpurpose>Free memory used by cstring.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>free-cstring</function> <replaceable>cstring</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>cstring</parameter></term>
- <listitem>
- <para>A cstring.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Frees any memory possibly allocated by
- <function>convert-to-cstring</function>. On some implementions, a cstring is just the Lisp string itself.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="with-cstring">
- <refnamediv>
- <refname>with-cstring</refname>
- <refpurpose>Binds a newly created cstring.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>with-cstring</function> <replaceable>(cstring string) {body}</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>cstring</parameter></term>
- <listitem>
- <para>A symbol naming the cstring to be created.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>string</parameter></term>
- <listitem>
- <para>A Lisp string that will be translated to a cstring.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>body</parameter></term>
- <listitem>
- <para>The body of where the cstring will be bound.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Binds a symbol to a cstring created from conversion of a string. Automatically frees the <varname>cstring</varname>.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <para>
- <programlisting>
-(def-function ("getenv" c-getenv)
- ((name :cstring))
- :returning :cstring)
-
-(defun getenv (key)
- "Returns an environment variable, or NIL if it does not exist"
- (check-type key string)
- (with-cstring (key-cstring key)
- (convert-from-cstring (c-getenv key-cstring))))
- </programlisting>
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="convert-from-foreign-string">
- <refnamediv>
- <refname>convert-from-foreign-string</refname>
- <refpurpose>Converts a foreign string into a Lisp string.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>convert-from-foreign-string</function> <replaceable>foreign-string &key length null-terminated-p</replaceable> => <returnvalue>string</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>foreign-string</parameter></term>
- <listitem>
- <para>A foreign string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>length</parameter></term>
- <listitem>
- <para>The length of the foreign string to
-convert. The default is the length of the string until a &null;
-character is reached.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>null-terminated-p</parameter></term>
- <listitem>
- <para>A boolean flag with a default value of &t; When true,
-the string is converted until the first &null; character is reached.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>string</returnvalue></term>
- <listitem>
- <para>A Lisp string.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Returns a Lisp string from a foreign string.
-Can translated ASCII and binary strings.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
- <refentry id="convert-to-foreign-string">
- <refnamediv>
- <refname>convert-to-foreign-string</refname>
- <refpurpose>Converts a Lisp string to a foreign string.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>convert-to-foreign-string</function> <replaceable>string</replaceable> => <returnvalue>foreign-string</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>string</parameter></term>
- <listitem>
- <para>A Lisp string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>foreign-string</returnvalue></term>
- <listitem>
- <para>A foreign string.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Converts a Lisp string to a foreign string. Memory should be
- freed with <function>free-foreign-object</function>.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-
-
- <refentry id="allocate-foreign-string">
- <refnamediv>
- <refname>allocate-foreign-string</refname>
- <refpurpose>Allocates space for a foreign string.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>allocate-foreign-string</function> <replaceable>size &key unsigned</replaceable> => <returnvalue>foreign-string</returnvalue>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>size</parameter></term>
- <listitem>
- <para>The size of the space to be allocated in bytes.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>unsigned</parameter></term>
- <listitem>
- <para>A boolean flag with a default value of &t;. When true,
-marks the pointer as an <constant>:unsigned-char</constant>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>foreign-string</returnvalue></term>
- <listitem>
- <para>A foreign string which has undefined contents.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>
- Allocates space for a foreign string. Memory should
- be freed with <function>free-foreign-object</function>.
- </para>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- </reference>
-
- <reference>
- <title>Functions & Libraries</title>
-
- <refentry id="def-function">
- <refnamediv>
- <refname>def-function</refname>
- <refpurpose>Declares a function.
- </refpurpose>
- <refclass>Macro</refclass>
- </refnamediv>
- <refsynopsisdiv>
- <title>Syntax</title>
- <synopsis>
- <function>def-function</function> <replaceable>name args &key module returning</replaceable>
- </synopsis>
- </refsynopsisdiv>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>name</parameter></term>
- <listitem>
- <para>A string or list specificying the function name. If it is a string, that names the foreign function. A Lisp name is created by translating #\_ to #\- and by converting to upper-case in case-insensitive Lisp implementations. If it is a list, the first item is a string specifying the foreign function name and the second it is a symbol stating the Lisp name.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>args</parameter></term>
- <listitem>
- <para>A list of argument declarations. If &nil;, indicates that the function does not take any arguments.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>module</parameter></term>
- <listitem>
- <para>A string specifying which module (or library) that the foreign function resides. (Required by Lispworks)</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>returning</returnvalue></term>
- <listitem>
- <para>A declaration specifying the result type of the
-foreign function. If <constant>:void</constant> indicates module does not return any value.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>Declares a foreign function.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(def-function "gethostname"
- ((name (* :unsigned-char))
- (len :int))
- :returning :int)
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="load-foreign-library">
- <refnamediv>
- <refname>load-foreign-library</refname>
- <refpurpose>Loads a foreign library.
- </refpurpose>
- <refclass>Function</refclass>
- </refnamediv>
- <refsect1>
- <title>Syntax</title>
-<synopsis>
- <function>load-foreign-library</function> <replaceable>filename &key module supporting-libraries force-load</replaceable> => <returnvalue>success</returnvalue>
-</synopsis>
- </refsect1>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>filename</parameter></term>
- <listitem>
- <para>A string or pathname specifying the library location
-in the filesystem. At least one implementation (&lw;) can not
-accept a logical pathname.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>module</parameter></term>
- <listitem>
- <para>A string designating the name of the module to apply
-to functions in this library. (Required for Lispworks)
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>supporting-libraries</parameter></term>
- <listitem>
- <para>A list of strings naming the libraries required to
-link the foreign library. (Required by CMUCL)
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>force-load</parameter></term>
- <listitem>
- <para>Forces the loading of the library if it has been previously loaded.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>success</returnvalue></term>
- <listitem>
- <para>A boolean flag, &t; if the library was able to be
-loaded successfully or if the library has been previously loaded,
-otherwise &nil;.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>Loads a foreign library. Applies a module name to functions
-within the library. Ensures that a library is only loaded once during
-a session. A library can be reloaded by using the <symbol>:force-load</symbol> key.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
- (load-foreign-library #p"/usr/lib/libmysqlclient.so"
- :module "mysql"
- :supporting-libraries '("c"))
- => T
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>Loads the foreign code into the Lisp system.
- </para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>Ability to load the file.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
- <refentry id="find-foreign-library">
- <refnamediv>
- <refname>find-foreign-library</refname>
- <refpurpose>Finds a foreign library file.
- </refpurpose>
- <refclass>Function</refclass>
- </refnamediv>
- <refsect1>
- <title>Syntax</title>
-<synopsis>
- <function>find-foreign-library</function> <replaceable>names directories & drive-letters types</replaceable> => <returnvalue>path</returnvalue>
-</synopsis>
- </refsect1>
- <refsect1>
- <title>Arguments and Values</title>
- <variablelist>
- <varlistentry>
- <term><parameter>names</parameter></term>
- <listitem>
- <para>A string or list of strings containing the base name of the library file.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>directories</parameter></term>
- <listitem>
- <para>A string or list of strings containing the directory the library file.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>drive-letters</parameter></term>
- <listitem>
- <para>A string or list of strings containing the drive letters for the library file.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>types</parameter></term>
- <listitem>
- <para>A string or list of strings containing the file type of the library file. Default
-is &nil;. If &nil;, will use a default type based on the currently running implementation.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><returnvalue>path</returnvalue></term>
- <listitem>
- <para>A path containing the path found, or &nil; if the library file was not found.
- </para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
- <refsect1>
- <title>Description</title>
- <para>Finds a foreign library by searching through a number of possible locations. Returns
-the path of the first found file.
- </para>
- </refsect1>
- <refsect1>
- <title>Examples</title>
- <programlisting>
-(find-foreign-library '("libmysqlclient" "libmysql")
- '("/opt/mysql/lib/mysql/" "/usr/local/lib/" "/usr/lib/" "/mysql/lib/opt/")
- :types '("so" "dll")
- :drive-letters '("C" "D" "E"))
-=> #P"D:\\mysql\\lib\\opt\\libmysql.dll"
- </programlisting>
- </refsect1>
- <refsect1>
- <title>Side Effects</title>
- <para>None.
- </para>
- </refsect1>
- <refsect1>
- <title>Affected by</title>
- <para>None.</para>
- </refsect1>
- <refsect1>
- <title>Exceptional Situations</title>
- <para>None.</para>
- </refsect1>
- </refentry>
-
-</reference>
-
-
-<appendix>
- <title>Installation</title>
- <sect1>
- <title>Download &uffi;</title>
- <para>
-You need to download the &uffi; package from its web
-<ulink url="http://uffi.med-info.com"><citetitle>home</citetitle></ulink>.
-You also need to have a copy of &asdf;. If you need a copy of
-&asdf;, it is included in the
- <ulink
- url="http://www.sourceforge.net/projects/cclan">
- <citetitle>CCLAN</citetitle></ulink> package. You can download
-the file <filename>defsystem.lisp</filename> from the CVS
-<ulink url="http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/cclan/asdf/asdf.lisp"><citetitle>tree</citetitle></ulink>.
- </para>
- </sect1>
- <sect1>
- <title>Installation</title>
- <para>
- After downloading and installing &asdf;, simply
- <function>push</function> the
- directory containing &uffi; into
- <varname>asdf:*central-registry*</varname> variable. Whenever you
-want to load the &uffi; package, use the function
- <computeroutput>(asdf:oos 'asdf:load-op :uffi)</computeroutput>.
- </para>
- </sect1>
-</appendix>
-
-
-<glossary>
- <glossentry id="gloss-ffi">
- <glossterm>Foreign Function Interface
- <acronym>FFI</acronym>)
- </glossterm>
- <glossdef>
- <para>
- An interface to a C-compatible library.
- </para>
- </glossdef>
- </glossentry>
-</glossary>
-
-