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diff --git a/doc/sources/libguile-tools.texi b/doc/sources/libguile-tools.texi deleted file mode 100644 index d434406e9..000000000 --- a/doc/sources/libguile-tools.texi +++ /dev/null @@ -1,191 +0,0 @@ -@node Tools to automate adding libraries -@chapter Tools to automate adding libraries - -You want to ... - -The chapters @ref{Libguile -- high level interface} and @ref{Libguile -- -SCM interface} showed how to make C libraries available from Scheme. -Here I will describe some automated tools that the Guile team has made -available. Some have been written especially for Guile (the Guile Magic -Snarfer), and some are also in use with other languages (Python, Perl, -...) - -@menu -* By hand with gh_:: -* By hand with Guile Magic Snarfer:: -* Automatically using libtool:: -* Automatically using SWIG:: -@end menu - -@node By hand with gh_ -@section By hand with gh_ - -@node By hand with Guile Magic Snarfer -@section By hand with Guile Magic Snarfer - -When writing C code for use with Guile, you typically define a set of C -functions, and then make some of them visible to the Scheme world by -calling the @code{scm_make_gsubr} function; a C functions published in -this way is called a @dfn{subr}. If you have many subrs to publish, it -can sometimes be annoying to keep the list of calls to -@code{scm_make_gsubr} in sync with the list of function definitions. -Frequently, a programmer will define a new subr in C, recompile his -application, and then discover that the Scheme interpreter cannot see -the subr, because he forgot to call @code{scm_make_gsubr}. - -Guile provides the @code{guile-snarf} command to manage this problem. -Using this tool, you can keep all the information needed to define the -subr alongside the function definition itself; @code{guile-snarf} will -extract this information from your source code, and automatically -generate a file of calls to @code{scm_make_gsubr} which you can -@code{#include} into an initialization function. (The command name -comes from the verb ``to snarf'', here meaning ``to unceremoniously -extract information from a somewhat unwilling source.'') - -@menu -* How guile-snarf works:: Using the @code{guile-snarf} command. -* Macros guile-snarf recognizes:: How to mark up code for @code{guile-snarf}. -@end menu - -@node How guile-snarf works -@subsection How @code{guile-snarf} works - -For example, here is how you might define a new subr called -@code{clear-image}, implemented by the C function @code{clear_image}: - -@example -@group -#include <libguile.h> - -@dots{} - -SCM_PROC (s_clear_image, "clear-image", 1, 0, 0, clear_image); - -SCM -clear_image (SCM image_smob) -@{ - @dots{} -@} - -@dots{} - -void -init_image_type () -@{ -#include "image-type.x" -@} -@end group -@end example - -The @code{SCM_PROC} declaration says that the C function -@code{clear_image} implements a Scheme subr called @code{clear-image}, -which takes one required argument, no optional arguments, and no tail -argument. @code{SCM_PROC} also declares a static array of characters -named @code{s_clear_image}, initialized to the string -@code{"clear-image"}. The body of @code{clear_image} may use the array -in error messages, instead of writing out the literal string; this may -save string space on some systems. - -Assuming the text above lives in a file named @file{image-type.c}, you will -need to execute the following command to compile this file: -@example -guile-snarf image-type.c > image-type.x -@end example -@noindent This scans @file{image-type.c} for @code{SCM_PROC} -declarations, and sends the following output to the file -@file{image-type.x}: -@example -scm_make_gsubr (s_clear_image, 1, 0, 0, clear_image); -@end example -When compiled normally, @code{SCM_PROC} is a macro which expands to a -declaration of the @code{s_clear_image} string. - -In other words, @code{guile-snarf} scans source code looking for uses of -the @code{SCM_PROC} macro, and generates C code to define the -appropriate subrs. You need to provide all the same information you -would if you were using @code{scm_make_gsubr} yourself, but you can -place the information near the function definition itself, so it is less -likely to become incorrect or out-of-date. - -If you have many files that @code{guile-snarf} must process, you should -consider using a rule like the following in your Makefile: -@example -.SUFFIXES: .x -.c.x: - ./guile-snarf $(DEFS) $(INCLUDES) $(CPPFLAGS) $(CFLAGS) $< > $@ -@end example -This tells make to run @code{guile-snarf} to produce each needed -@file{.x} file from the corresponding @file{.c} file. - -@code{guile-snarf} passes all its command-line arguments directly to the -C preprocessor, which it uses to extract the information it needs from -the source code. this means you can pass normal compilation flags to -@code{guile-snarf} to define preprocessor symbols, add header file -directories, and so on. - - - -@node Macros guile-snarf recognizes -@subsection Macros @code{guile-snarf} recognizes - -Here are the macros you can use in your source code from which -@code{guile-snarf} can construct initialization code: - - -@defmac SCM_PROC (@var{namestr}, @var{name}, @var{req}, @var{opt}, @var{tail}, @var{c_func}) -Declare a new Scheme primitive function, or @dfn{subr}. The new subr -will be named @var{name} in Scheme code, and be implemented by the C -function @var{c_func}. The subr will take @var{req} required arguments -and @var{opt} optional arguments. If @var{tail} is non-zero, the -function will accept any remaining arguments as a list. - -Use this macro outside all function bodies, preferably above the -definition of @var{c_func} itself. When compiled, the @code{SCM_PROC} -declaration will expand to a definition for the @var{namestr} array, -initialized to @var{name}. The @code{guile-snarf} command uses this -declaration to automatically generate initialization code to create the -subr and bind it in the top-level environment. @xref{How guile-snarf -works}, for more info. - -@xref{Subrs}, for details on argument passing and how to write -@var{c_func}. -@end defmac - - -@defmac SCM_GLOBAL (@var{var}, @var{scheme_name}) -Declare a global Scheme variable named @var{scheme_name}, and a static C -variable named @var{var} to point to it. The value of the Scheme -variable lives in the @sc{cdr} of the cell @var{var} points to. -Initialize the variable to @code{#f}. - -Use this macro outside all function bodies. When compiled, the -@code{SCM_GLOBAL} macro will expand to a definition for the variable -@var{var}, initialized to an innocuous value. The @code{guile-snarf} -command will use this declaration to automatically generate code to -create a global variable named @var{scheme_name}, and store a pointer to -its cell in @var{var}. -@end defmac - - -@defmac SCM_CONST_LONG (@var{var}, @var{scheme_name}, @var{value}) -Like @code{SCM_GLOBAL}, but initialize the variable to @var{value}, -which must be an integer. -@end defmac - - -@defmac SCM_SYMBOL (@var{var}, @var{name}) -Declare a C variable of type @code{SCM} named @var{var}, and initialize -it to the Scheme symbol object whose name is @var{name}. - -Use this macro outside all function bodies. When compiled, the -@code{SCM_SYMBOL} macro will expand to a definition for the variable -@var{var}, initialized to an innocuous value. The @code{guile-snarf} -command will use this declaration to automatically generate code to -create a symbol named @var{name}, and store it in @var{var}. -@end defmac - -@node Automatically using libtool -@section Automatically using libtool - -@node Automatically using SWIG -@section Automatically using SWIG |