newlib-cygwin/winsup/cygwin/dlfcn.cc

170 lines
3.9 KiB
C++

/* dlfcn.cc
Copyright 1998, 2000, 2001, 2002, 2003, 2004 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include <psapi.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <ctype.h>
#include "cygerrno.h"
#include "security.h"
#include "path.h"
#include "fhandler.h"
#include "perprocess.h"
#include "thread.h"
#include "dlfcn.h"
#include "dll_init.h"
#include "cygtls.h"
static void __stdcall
set_dl_error (const char *str)
{
strcpy (_my_tls.locals.dl_buffer, strerror (get_errno ()));
_my_tls.locals.dl_error = 1;
}
/* Look for an executable file given the name and the environment
variable to use for searching (eg., PATH); returns the full
pathname (static buffer) if found or NULL if not. */
inline const char * __stdcall
check_path_access (const char *mywinenv, const char *name, path_conv& buf)
{
return find_exec (name, buf, mywinenv, FE_NNF | FE_NATIVE | FE_CWD | FE_DLL);
}
/* Search LD_LIBRARY_PATH for dll, if it exists.
Return Windows version of given path. */
static const char * __stdcall
get_full_path_of_dll (const char* str, char *name)
{
int len = strlen (str);
/* empty string or too long to be legal win32 pathname? */
if (len == 0 || len >= CYG_MAX_PATH)
return str; /* Yes. Let caller deal with it. */
const char *ret;
strcpy (name, str); /* Put it somewhere where we can manipulate it. */
/* Add extension if necessary */
if (str[len - 1] != '.')
{
/* Add .dll only if no extension provided. */
const char *p = strrchr (str, '.');
if (!p || strpbrk (p, "\\/"))
strcat (name, ".dll");
}
path_conv real_filename;
if (isabspath (name) ||
(ret = check_path_access ("LD_LIBRARY_PATH=", name, real_filename)
?: check_path_access ("/usr/lib", name, real_filename)) == NULL)
real_filename.check (name, PC_SYM_FOLLOW | PC_NOFULL | PC_NULLEMPTY); /* Convert */
if (!real_filename.error)
ret = strcpy (name, real_filename);
else
{
set_errno (real_filename.error);
ret = NULL;
}
return ret;
}
void *
dlopen (const char *name, int)
{
void *ret;
if (name == NULL)
ret = (void *) GetModuleHandle (NULL); /* handle for the current module */
else
{
char buf[CYG_MAX_PATH];
/* handle for the named library */
const char *fullpath = get_full_path_of_dll (name, buf);
if (!fullpath)
ret = NULL;
else
{
ret = (void *) LoadLibrary (fullpath);
if (ret == NULL)
__seterrno ();
}
}
if (!ret)
set_dl_error ("dlopen");
debug_printf ("ret %p", ret);
return ret;
}
void *
dlsym (void *handle, const char *name)
{
void *ret = NULL;
if (handle == RTLD_DEFAULT)
{ /* search all modules */
HANDLE cur_proc = GetCurrentProcess ();
HMODULE *modules;
DWORD needed, i;
if (!EnumProcessModules (cur_proc, NULL, 0, &needed))
{
dlsym_fail:
set_dl_error ("dlsym");
return NULL;
}
modules = (HMODULE*) alloca (needed);
if (!EnumProcessModules (cur_proc, modules, needed, &needed))
goto dlsym_fail;
for (i = 0; i < needed / sizeof (HMODULE); i++)
if ((ret = (void *) GetProcAddress (modules[i], name)))
break;
}
else
ret = (void *) GetProcAddress ((HMODULE)handle, name);
if (!ret)
set_dl_error ("dlsym");
debug_printf ("ret %p", ret);
return ret;
}
int
dlclose (void *handle)
{
int ret = -1;
void *temphandle = (void *) GetModuleHandle (NULL);
if (temphandle == handle || FreeLibrary ((HMODULE) handle))
ret = 0;
if (ret)
set_dl_error ("dlclose");
CloseHandle ((HMODULE) temphandle);
return ret;
}
char *
dlerror ()
{
char *res;
if (!_my_tls.locals.dl_error)
res = NULL;
else
{
_my_tls.locals.dl_error = 0;
res = _my_tls.locals.dl_buffer;
}
return res;
}