X-Git-Url: http://git.hcoop.net/bpt/guile.git/blobdiff_plain/e2ab7927bfab05cb08b611ec8827258a395b72ae..9bc6fb0a7d91ae9a6c57cedb76022043db413ba5:/libguile/extensions.c

diff --git a/libguile/extensions.c b/libguile/extensions.c
index 3d4f7d8cd..83bcee2a1 100644
--- a/libguile/extensions.c
+++ b/libguile/extensions.c
@@ -41,6 +41,8 @@
  * whether to permit this exception to apply to your modifications.
  * If you do not wish that, delete this exception notice.  */
 
+#include <string.h>
+
 #include "libguile/_scm.h"
 #include "libguile/strings.h"
 #include "libguile/gc.h"
@@ -48,24 +50,36 @@
 
 #include "libguile/extensions.h"
 
-struct extension {
-  struct extension *next;
+typedef struct extension_t
+{
+  struct extension_t *next;
   const char *lib;
   const char *init;
   void (*func)(void *);
   void *data;
-};
+} extension_t;
 
-static struct extension *registered_extensions;
+static extension_t *registered_extensions;
+
+/* Register a LIB/INIT pair for use by `scm_load_extension'.  LIB is
+   allowed to be NULL and then only INIT is used to identify the
+   registered entry.  This is useful when you don't know the library
+   name (which isn't really relevant anyway in a completely linked
+   program) and you are sure that INIT is unique (which it must be for
+   static linking).  Hmm, given this reasoning, what use is LIB
+   anyway?
+*/
 
 void
 scm_c_register_extension (const char *lib, const char *init,
 			  void (*func) (void *), void *data)
 {
-  struct extension *ext = scm_must_malloc (sizeof(struct extension),
-					   "scm_register_extension");
-  ext->lib = scm_must_strdup (lib);
-  ext->init = scm_must_strdup (init);
+  extension_t *ext = scm_malloc (sizeof(extension_t));
+  if (lib)
+    ext->lib = scm_strdup (lib);
+  else
+    ext->lib = NULL;
+  ext->init = scm_strdup (init);
   ext->func = func;
   ext->data = data;
 
@@ -78,10 +92,10 @@ load_extension (SCM lib, SCM init)
 {
   /* Search the registry. */
   {
-    struct extension *ext;
+    extension_t *ext;
 
     for (ext = registered_extensions; ext; ext = ext->next)
-      if (!strcmp (ext->lib, SCM_STRING_CHARS (lib))
+      if ((ext->lib == NULL || !strcmp (ext->lib, SCM_STRING_CHARS (lib)))
 	  && !strcmp (ext->init, SCM_STRING_CHARS (init)))
 	{
 	  ext->func (ext->data);
@@ -102,36 +116,40 @@ scm_c_load_extension (const char *lib, const char *init)
 
 SCM_DEFINE (scm_load_extension, "load-extension", 2, 0, 0,
 	    (SCM lib, SCM init),
-	    "Load and initilize the extension designated by LIB and INIT."
-"When there is no pre-registered function for LIB/INIT, this is "
-"equivalent to "
-" "
-"   (dynamic-call INIT (dynamic-link LIB)) "
-" "
-"When there is a pre-registered function, that function is called "
-"instead. "
-" "
-"Normally, there is no pre-registered function.  This option exists "
-"only for situations where dynamic linking is unavailable or unwanted. "
-"In that case, you would statically link your program with the desired "
-"library, and register its init function right after Guile has been "
-"initialized. "
-" "
-"LIB should be a string denoting a shared library without any file type "
-"suffix such as \".so\".  The suffix is provided automatically.  It "
-"should also not contain any directory components.  Libraries that "
-"implement Guile Extensions should be put into the normal locations for "
-"shared libraries.  We recommend to use the naming convention "
-"libguile-bla-blum for a extension related to a module `(bla blum)'. "
-" "
-"The normal way for a extension to be used is to write a small Scheme "
-"file that defines a module, and to load the extension into this "
-"module.  When the module is auto-loaded, the extension is loaded as "
-"well.  For example, "
-" "
-"   (define-module (bla blum)) "
-" "
-"   (load-extension \"libguile-bla-blum\" \"bla_init_blum\")")
+	    "Load and initialize the extension designated by LIB and INIT.\n"
+	    "When there is no pre-registered function for LIB/INIT, this is\n"
+	    "equivalent to\n"
+	    "\n"
+	    "@lisp\n"
+	    "(dynamic-call INIT (dynamic-link LIB))\n"
+	    "@end lisp\n"
+	    "\n"
+	    "When there is a pre-registered function, that function is called\n"
+	    "instead.\n"
+	    "\n"
+	    "Normally, there is no pre-registered function.  This option exists\n"
+	    "only for situations where dynamic linking is unavailable or unwanted.\n"
+	    "In that case, you would statically link your program with the desired\n"
+	    "library, and register its init function right after Guile has been\n"
+	    "initialized.\n"
+	    "\n"
+	    "LIB should be a string denoting a shared library without any file type\n"
+	    "suffix such as \".so\".  The suffix is provided automatically.  It\n"
+	    "should also not contain any directory components.  Libraries that\n"
+	    "implement Guile Extensions should be put into the normal locations for\n"
+	    "shared libraries.  We recommend to use the naming convention\n"
+	    "libguile-bla-blum for a extension related to a module `(bla blum)'.\n"
+	    "\n"
+	    "The normal way for a extension to be used is to write a small Scheme\n"
+	    "file that defines a module, and to load the extension into this\n"
+	    "module.  When the module is auto-loaded, the extension is loaded as\n"
+	    "well.  For example,\n"
+	    "\n"
+	    "@lisp\n"
+	    "(define-module (bla blum))\n"
+	    "\n"
+	    "(load-extension \"libguile-bla-blum\" \"bla_init_blum\")\n"
+	    "@end lisp")
 #define FUNC_NAME s_scm_load_extension
 {
   SCM_VALIDATE_STRING (1, lib);