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/*
* Copyright (c) 1997 The XFree86 Project, Inc.
*
* Permission to use, copy, modify, distribute, and sell this software
* and its documentation for any purpose is hereby granted without
* fee, provided that the above copyright notice appear in all copies
* and that both that copyright notice and this permission notice
* appear in supporting documentation, and that the name of the
* XFree86 Project, Inc. not be used in advertising or publicity
* pertaining to distribution of the software without specific,
* written prior permission. The Xfree86 Project, Inc. makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
*
* THE XFREE86 PROJECT, INC. DISCLAIMS ALL WARRANTIES WITH REGARD TO
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS, IN NO EVENT SHALL THE XFREE86 PROJECT, INC. BE LIABLE
* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
/*
* Once upon a time, X had multiple loader backends, three of which were
* essentially libdl reimplementations. This was nonsense so we chucked
* it, but we still retain the factorization between loader API and
* platform implementation. This file is the libdl implementation, and
* currently the only backend. If you find yourself porting to a platform
* without working libdl - hpux, win32, some forsaken a.out host, etc. -
* make a new backend rather than hacking up this file.
*/
#ifdef HAVE_XORG_CONFIG_H
#include <xorg-config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <dlfcn.h>
#include <X11/Xos.h>
#include "os.h"
#include "loader.h"
#include "dlloader.h"
#if defined(DL_LAZY)
#define DLOPEN_LAZY DL_LAZY
#elif defined(RTLD_LAZY)
#define DLOPEN_LAZY RTLD_LAZY
#elif defined(__FreeBSD__)
#define DLOPEN_LAZY 1
#else
#define DLOPEN_LAZY 0
#endif
#if defined(LD_GLOBAL)
#define DLOPEN_GLOBAL LD_GLOBAL
#elif defined(RTLD_GLOBAL)
#define DLOPEN_GLOBAL RTLD_GLOBAL
#else
#define DLOPEN_GLOBAL 0
#endif
#if defined(CSRG_BASED) && !defined(__ELF__)
#define DLSYM_PREFIX "_"
#else
#define DLSYM_PREFIX ""
#endif
/* Hooray, yet another open coded linked list! FIXME */
typedef struct DLModuleList {
void *module;
struct DLModuleList *next;
} DLModuleList;
static DLModuleList *dlModuleList = NULL;
static void *
DLFindSymbolLocal(pointer module, const char *name)
{
void *p;
char *n;
static const char symPrefix[] = DLSYM_PREFIX;
if (strlen(symPrefix)) {
n = malloc(strlen(symPrefix) + strlen(name) + 1);
sprintf(n, "%s%s", symPrefix, name);
} else {
n = name;
}
p = dlsym(module, n);
if (strlen(symPrefix))
free(n);
return p;
}
static void *global_scope = NULL;
void *
DLFindSymbol(const char *name)
{
DLModuleList *l;
void *p;
p = dlsym(RTLD_DEFAULT, name);
if (p != NULL)
return p;
for (l = dlModuleList; l != NULL; l = l->next) {
p = DLFindSymbolLocal(l->module, name);
if (p)
return p;
}
if (!global_scope)
global_scope = dlopen(NULL, DLOPEN_LAZY | DLOPEN_GLOBAL);
if (global_scope)
return DLFindSymbolLocal(global_scope, name);
return NULL;
}
void *
DLLoadModule(loaderPtr modrec, int flags)
{
void * dlfile;
DLModuleList *l;
int dlopen_flags;
if (flags & LD_FLAG_GLOBAL)
dlopen_flags = DLOPEN_LAZY | DLOPEN_GLOBAL;
else
dlopen_flags = DLOPEN_LAZY;
dlfile = dlopen(modrec->name, dlopen_flags);
if (dlfile == NULL) {
ErrorF("dlopen: %s\n", dlerror());
return NULL;
}
l = malloc(sizeof(DLModuleList));
l->module = dlfile;
l->next = dlModuleList;
dlModuleList = l;
return (void *)dlfile;
}
void
DLUnloadModule(void *modptr)
{
DLModuleList *l, *p;
/* remove it from dlModuleList. */
if (dlModuleList->module == modptr) {
l = dlModuleList;
dlModuleList = l->next;
free(l);
} else {
p = dlModuleList;
for (l = dlModuleList->next; l != NULL; l = l->next) {
if (l->module == modptr) {
p->next = l->next;
free(l);
break;
}
p = l;
}
}
dlclose(modptr);
}
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