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/* objc-load - Dynamically load in Obj-C modules (Classes, Categories)
Copyright (C) 1995 Free Software Foundation, Inc.
Written by: Adam Fedor, Pedja Bogdanovich
This file is part of the GNU Objective C Class Library.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
CAVEATS:
- unloading modules not implemented
- would like to raise exceptions without having to turn this into
a .m file (right now NSBundle does this for us, ok?)
*/
#include <stdio.h>
#include <stdlib.h>
#include <objc/objc-api.h>
#include <objc/list.h>
#include <Foundation/objc-load.h>
/* include the interface to the dynamic linker */
#include "dynamic-load.h"
/* From the objc runtime -- needed when invalidating the dtable */
extern void __objc_install_premature_dtable(Class);
extern void sarray_free(struct sarray*);
extern struct sarray *__objc_uninstalled_dtable;
/* Declaration from NSBundle.m */
const char *objc_executable_location( void );
/* This is the GNU name for the CTOR list */
#define CTOR_LIST "___CTOR_LIST__"
/* dynamic_loaded is YES if the dynamic loader was sucessfully initialized. */
static BOOL dynamic_loaded;
/* Our current callback function */
void (*_objc_load_load_callback)(Class, Category*) = 0;
/* List of modules we have loaded (by handle) */
static struct objc_list *dynamic_handles = NULL;
/* Check to see if there are any undefined symbols. Print them out.
*/
static int
objc_check_undefineds(FILE *errorStream)
{
int count = __objc_dynamic_undefined_symbol_count();
if (count != 0) {
int i;
char **undefs;
undefs = __objc_dynamic_list_undefined_symbols();
if (errorStream)
fprintf(errorStream, "Undefined symbols:\n");
for (i=0; i < count; i++)
if (errorStream)
fprintf(errorStream, " %s\n", undefs[i]);
return 1;
}
return 0;
}
/* Invalidate the dtable so it will be rebuild when a message is sent to
the object */
static void
objc_invalidate_dtable(Class class)
{
Class s;
if (class->dtable == __objc_uninstalled_dtable)
return;
sarray_free(class->dtable);
__objc_install_premature_dtable(class);
for (s=class->subclass_list; s; s=s->sibling_class)
objc_invalidate_dtable(s);
}
/* Initialize for dynamic loading */
static int
objc_initialize_loading(FILE *errorStream)
{
const char *path;
dynamic_loaded = NO;
path = objc_executable_location();
#ifdef DEBUG
printf("Debug (objc-load): initializing dynamic loader for %s\n", path);
#endif
if (__objc_dynamic_init(path)) {
if (errorStream)
__objc_dynamic_error(errorStream, "Error (objc-load): Cannot initialize dynamic linker");
return 1;
} else
dynamic_loaded = YES;
return 0;
}
/* A callback received from the Object initializer (_objc_exec_class).
Do what we need to do and call our own callback.
*/
static void
objc_load_callback(Class class, Category* category)
{
/* Invalidate the dtable, so it will be rebuilt correctly */
if (class != 0 && category != 0) {
objc_invalidate_dtable(class);
objc_invalidate_dtable(class->class_pointer);
}
if (_objc_load_load_callback)
_objc_load_load_callback(class, category);
}
long
objc_load_module(
const char *filename,
FILE *errorStream,
void (*loadCallback)(Class, Category*),
void **header,
char *debugFilename)
{
typedef void (*void_fn)();
void_fn *ctor_list;
dl_handle_t handle;
int i;
if (!dynamic_loaded)
if (objc_initialize_loading(errorStream))
return 1;
_objc_load_load_callback = loadCallback;
_objc_load_callback = objc_load_callback;
/* Link in the object file */
#ifdef DEBUG
printf("Debug (objc-load): Linking file %s\n", filename);
#endif
handle = __objc_dynamic_link(filename, 1, debugFilename);
if (handle == 0) {
if (errorStream)
__objc_dynamic_error(errorStream, "Error (objc-load)");
return 1;
}
dynamic_handles = list_cons(handle, dynamic_handles);
/* If there are any undefined symbols, we can't load the bundle */
if (objc_check_undefineds(errorStream)) {
__objc_dynamic_unlink(handle);
return 1;
}
#if !defined(__ELF__) && !defined(CON_AUTOLOAD)
/* Get the constructor list and load in the objects */
ctor_list = (void_fn *)__objc_dynamic_find_symbol(handle, CTOR_LIST);
if (!ctor_list) {
if (errorStream)
fprintf(errorStream, "Error (objc-load): Cannot load objects (no CTOR list)\n");
return 1;
}
#ifdef DEBUG
printf("Debug (objc-load): %d modules\n", (int)ctor_list[0]);
#endif
for (i=1; ctor_list[i]; i++) {
#ifdef DEBUG
printf("Debug (objc-load): Invoking CTOR %p\n", ctor_list[i]);
#endif
ctor_list[i]();
}
#endif /* not __ELF__ */
_objc_load_callback = 0;
_objc_load_load_callback = 0;
return 0;
}
long
objc_unload_module(
FILE *errorStream,
void (*unloadCallback)(Class, Category*))
{
if (!dynamic_loaded)
return 1;
if (errorStream)
fprintf(errorStream, "Warning: unloading modules not implemented\n");
return 0;
}
long objc_loadModules(char *files[],FILE *errorStream,
void (*callback)(Class,Category*),
void **header,
char *debugFilename)
{
while (*files) {
if (objc_load_module(*files, errorStream, callback,
(void *)header, debugFilename))
return 1;
files++;
}
return 0;
}
long
objc_unloadModules(
FILE *errorStream,
void (*unloadCallback)(Class, Category*))
{
if (!dynamic_loaded)
return 1;
if (errorStream)
fprintf(errorStream, "Warning: unloading modules not implemented\n");
return 0;
}
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