/* */
DEFINITIONS
This source file includes following definitions.
- w32_coredll
- w32_dlclose
- fiddle_handle_free
- fiddle_handle_memsize
- rb_fiddle_handle_close
- rb_fiddle_handle_s_allocate
- predefined_fiddle_handle
- rb_fiddle_handle_initialize
- rb_fiddle_handle_enable_close
- rb_fiddle_handle_disable_close
- rb_fiddle_handle_close_enabled_p
- rb_fiddle_handle_to_i
- rb_fiddle_handle_sym
- rb_fiddle_handle_s_sym
- fiddle_handle_sym
- Init_fiddle_handle
#include <ruby.h>
#include <fiddle.h>
#define SafeStringValueCStr(v) (rb_check_safe_obj(rb_string_value(&v)), StringValueCStr(v))
VALUE rb_cHandle;
struct dl_handle {
void *ptr;
int open;
int enable_close;
};
#ifdef _WIN32
# ifndef _WIN32_WCE
static void *
w32_coredll(void)
{
MEMORY_BASIC_INFORMATION m;
memset(&m, 0, sizeof(m));
if( !VirtualQuery(_errno, &m, sizeof(m)) ) return NULL;
return m.AllocationBase;
}
# endif
static int
w32_dlclose(void *ptr)
{
# ifndef _WIN32_WCE
if( ptr == w32_coredll() ) return 0;
# endif
if( FreeLibrary((HMODULE)ptr) ) return 0;
return errno = rb_w32_map_errno(GetLastError());
}
#define dlclose(ptr) w32_dlclose(ptr)
#endif
static void
fiddle_handle_free(void *ptr)
{
struct dl_handle *fiddle_handle = ptr;
if( fiddle_handle->ptr && fiddle_handle->open && fiddle_handle->enable_close ){
dlclose(fiddle_handle->ptr);
}
xfree(ptr);
}
static size_t
fiddle_handle_memsize(const void *ptr)
{
return sizeof(struct dl_handle);
}
static const rb_data_type_t fiddle_handle_data_type = {
"fiddle/handle",
{0, fiddle_handle_free, fiddle_handle_memsize,},
};
/*
* call-seq: close
*
* Close this handle.
*
* Calling close more than once will raise a Fiddle::DLError exception.
*/
static VALUE
rb_fiddle_handle_close(VALUE self)
{
struct dl_handle *fiddle_handle;
TypedData_Get_Struct(self, struct dl_handle, &fiddle_handle_data_type, fiddle_handle);
if(fiddle_handle->open) {
int ret = dlclose(fiddle_handle->ptr);
fiddle_handle->open = 0;
/* Check dlclose for successful return value */
if(ret) {
#if defined(HAVE_DLERROR)
rb_raise(rb_eFiddleError, "%s", dlerror());
#else
rb_raise(rb_eFiddleError, "could not close handle");
#endif
}
return INT2NUM(ret);
}
rb_raise(rb_eFiddleError, "dlclose() called too many times");
UNREACHABLE;
}
static VALUE
rb_fiddle_handle_s_allocate(VALUE klass)
{
VALUE obj;
struct dl_handle *fiddle_handle;
obj = TypedData_Make_Struct(rb_cHandle, struct dl_handle, &fiddle_handle_data_type, fiddle_handle);
fiddle_handle->ptr = 0;
fiddle_handle->open = 0;
fiddle_handle->enable_close = 0;
return obj;
}
static VALUE
predefined_fiddle_handle(void *handle)
{
VALUE obj = rb_fiddle_handle_s_allocate(rb_cHandle);
struct dl_handle *fiddle_handle = DATA_PTR(obj);
fiddle_handle->ptr = handle;
fiddle_handle->open = 1;
OBJ_FREEZE(obj);
return obj;
}
/*
* call-seq:
* new(library = nil, flags = Fiddle::RTLD_LAZY | Fiddle::RTLD_GLOBAL)
*
* Create a new handler that opens +library+ with +flags+.
*
* If no +library+ is specified or +nil+ is given, DEFAULT is used, which is
* the equivalent to RTLD_DEFAULT. See <code>man 3 dlopen</code> for more.
*
* lib = Fiddle::Handle.new
*
* The default is dependent on OS, and provide a handle for all libraries
* already loaded. For example, in most cases you can use this to access +libc+
* functions, or ruby functions like +rb_str_new+.
*/
static VALUE
rb_fiddle_handle_initialize(int argc, VALUE argv[], VALUE self)
{
void *ptr;
struct dl_handle *fiddle_handle;
VALUE lib, flag;
char *clib;
int cflag;
const char *err;
switch( rb_scan_args(argc, argv, "02", &lib, &flag) ){
case 0:
clib = NULL;
cflag = RTLD_LAZY | RTLD_GLOBAL;
break;
case 1:
clib = NIL_P(lib) ? NULL : SafeStringValueCStr(lib);
cflag = RTLD_LAZY | RTLD_GLOBAL;
break;
case 2:
clib = NIL_P(lib) ? NULL : SafeStringValueCStr(lib);
cflag = NUM2INT(flag);
break;
default:
rb_bug("rb_fiddle_handle_new");
}
#if defined(_WIN32)
if( !clib ){
HANDLE rb_libruby_handle(void);
ptr = rb_libruby_handle();
}
else if( STRCASECMP(clib, "libc") == 0
# ifdef RUBY_COREDLL
|| STRCASECMP(clib, RUBY_COREDLL) == 0
|| STRCASECMP(clib, RUBY_COREDLL".dll") == 0
# endif
){
# ifdef _WIN32_WCE
ptr = dlopen("coredll.dll", cflag);
# else
(void)cflag;
ptr = w32_coredll();
# endif
}
else
#endif
ptr = dlopen(clib, cflag);
#if defined(HAVE_DLERROR)
if( !ptr && (err = dlerror()) ){
rb_raise(rb_eFiddleError, "%s", err);
}
#else
if( !ptr ){
err = dlerror();
rb_raise(rb_eFiddleError, "%s", err);
}
#endif
TypedData_Get_Struct(self, struct dl_handle, &fiddle_handle_data_type, fiddle_handle);
if( fiddle_handle->ptr && fiddle_handle->open && fiddle_handle->enable_close ){
dlclose(fiddle_handle->ptr);
}
fiddle_handle->ptr = ptr;
fiddle_handle->open = 1;
fiddle_handle->enable_close = 0;
if( rb_block_given_p() ){
rb_ensure(rb_yield, self, rb_fiddle_handle_close, self);
}
return Qnil;
}
/*
* call-seq: enable_close
*
* Enable a call to dlclose() when this handle is garbage collected.
*/
static VALUE
rb_fiddle_handle_enable_close(VALUE self)
{
struct dl_handle *fiddle_handle;
TypedData_Get_Struct(self, struct dl_handle, &fiddle_handle_data_type, fiddle_handle);
fiddle_handle->enable_close = 1;
return Qnil;
}
/*
* call-seq: disable_close
*
* Disable a call to dlclose() when this handle is garbage collected.
*/
static VALUE
rb_fiddle_handle_disable_close(VALUE self)
{
struct dl_handle *fiddle_handle;
TypedData_Get_Struct(self, struct dl_handle, &fiddle_handle_data_type, fiddle_handle);
fiddle_handle->enable_close = 0;
return Qnil;
}
/*
* call-seq: close_enabled?
*
* Returns +true+ if dlclose() will be called when this handle is garbage collected.
*
* See man(3) dlclose() for more info.
*/
static VALUE
rb_fiddle_handle_close_enabled_p(VALUE self)
{
struct dl_handle *fiddle_handle;
TypedData_Get_Struct(self, struct dl_handle, &fiddle_handle_data_type, fiddle_handle);
if(fiddle_handle->enable_close) return Qtrue;
return Qfalse;
}
/*
* call-seq: to_i
*
* Returns the memory address for this handle.
*/
static VALUE
rb_fiddle_handle_to_i(VALUE self)
{
struct dl_handle *fiddle_handle;
TypedData_Get_Struct(self, struct dl_handle, &fiddle_handle_data_type, fiddle_handle);
return PTR2NUM(fiddle_handle);
}
static VALUE fiddle_handle_sym(void *handle, VALUE symbol);
/*
* Document-method: sym
*
* call-seq: sym(name)
*
* Get the address as an Integer for the function named +name+.
*/
static VALUE
rb_fiddle_handle_sym(VALUE self, VALUE sym)
{
struct dl_handle *fiddle_handle;
TypedData_Get_Struct(self, struct dl_handle, &fiddle_handle_data_type, fiddle_handle);
if( ! fiddle_handle->open ){
rb_raise(rb_eFiddleError, "closed handle");
}
return fiddle_handle_sym(fiddle_handle->ptr, sym);
}
#ifndef RTLD_NEXT
#define RTLD_NEXT NULL
#endif
#ifndef RTLD_DEFAULT
#define RTLD_DEFAULT NULL
#endif
/*
* Document-method: sym
*
* call-seq: sym(name)
*
* Get the address as an Integer for the function named +name+. The function
* is searched via dlsym on RTLD_NEXT.
*
* See man(3) dlsym() for more info.
*/
static VALUE
rb_fiddle_handle_s_sym(VALUE self, VALUE sym)
{
return fiddle_handle_sym(RTLD_NEXT, sym);
}
static VALUE
fiddle_handle_sym(void *handle, VALUE symbol)
{
#if defined(HAVE_DLERROR)
const char *err;
# define CHECK_DLERROR if ((err = dlerror()) != 0) { func = 0; }
#else
# define CHECK_DLERROR
#endif
void (*func)();
const char *name = SafeStringValueCStr(symbol);
#ifdef HAVE_DLERROR
dlerror();
#endif
func = (void (*)())(VALUE)dlsym(handle, name);
CHECK_DLERROR;
#if defined(FUNC_STDCALL)
if( !func ){
int i;
int len = (int)strlen(name);
char *name_n;
#if defined(__CYGWIN__) || defined(_WIN32) || defined(__MINGW32__)
{
char *name_a = (char*)xmalloc(len+2);
strcpy(name_a, name);
name_n = name_a;
name_a[len] = 'A';
name_a[len+1] = '\0';
func = dlsym(handle, name_a);
CHECK_DLERROR;
if( func ) goto found;
name_n = xrealloc(name_a, len+6);
}
#else
name_n = (char*)xmalloc(len+6);
#endif
memcpy(name_n, name, len);
name_n[len++] = '@';
for( i = 0; i < 256; i += 4 ){
sprintf(name_n + len, "%d", i);
func = dlsym(handle, name_n);
CHECK_DLERROR;
if( func ) break;
}
if( func ) goto found;
name_n[len-1] = 'A';
name_n[len++] = '@';
for( i = 0; i < 256; i += 4 ){
sprintf(name_n + len, "%d", i);
func = dlsym(handle, name_n);
CHECK_DLERROR;
if( func ) break;
}
found:
xfree(name_n);
}
#endif
if( !func ){
rb_raise(rb_eFiddleError, "unknown symbol \"%"PRIsVALUE"\"", symbol);
}
return PTR2NUM(func);
}
void
Init_fiddle_handle(void)
{
/*
* Document-class: Fiddle::Handle
*
* The Fiddle::Handle is the manner to access the dynamic library
*
* == Example
*
* === Setup
*
* libc_so = "/lib64/libc.so.6"
* => "/lib64/libc.so.6"
* @handle = Fiddle::Handle.new(libc_so)
* => #<Fiddle::Handle:0x00000000d69ef8>
*
* === Setup, with flags
*
* libc_so = "/lib64/libc.so.6"
* => "/lib64/libc.so.6"
* @handle = Fiddle::Handle.new(libc_so, Fiddle::RTLD_LAZY | Fiddle::RTLD_GLOBAL)
* => #<Fiddle::Handle:0x00000000d69ef8>
*
* See RTLD_LAZY and RTLD_GLOBAL
*
* === Addresses to symbols
*
* strcpy_addr = @handle['strcpy']
* => 140062278451968
*
* or
*
* strcpy_addr = @handle.sym('strcpy')
* => 140062278451968
*
*/
rb_cHandle = rb_define_class_under(mFiddle, "Handle", rb_cObject);
rb_define_alloc_func(rb_cHandle, rb_fiddle_handle_s_allocate);
rb_define_singleton_method(rb_cHandle, "sym", rb_fiddle_handle_s_sym, 1);
rb_define_singleton_method(rb_cHandle, "[]", rb_fiddle_handle_s_sym, 1);
/* Document-const: NEXT
*
* A predefined pseudo-handle of RTLD_NEXT
*
* Which will find the next occurrence of a function in the search order
* after the current library.
*/
rb_define_const(rb_cHandle, "NEXT", predefined_fiddle_handle(RTLD_NEXT));
/* Document-const: DEFAULT
*
* A predefined pseudo-handle of RTLD_DEFAULT
*
* Which will find the first occurrence of the desired symbol using the
* default library search order
*/
rb_define_const(rb_cHandle, "DEFAULT", predefined_fiddle_handle(RTLD_DEFAULT));
/* Document-const: RTLD_GLOBAL
*
* rtld Fiddle::Handle flag.
*
* The symbols defined by this library will be made available for symbol
* resolution of subsequently loaded libraries.
*/
rb_define_const(rb_cHandle, "RTLD_GLOBAL", INT2NUM(RTLD_GLOBAL));
/* Document-const: RTLD_LAZY
*
* rtld Fiddle::Handle flag.
*
* Perform lazy binding. Only resolve symbols as the code that references
* them is executed. If the symbol is never referenced, then it is never
* resolved. (Lazy binding is only performed for function references;
* references to variables are always immediately bound when the library
* is loaded.)
*/
rb_define_const(rb_cHandle, "RTLD_LAZY", INT2NUM(RTLD_LAZY));
/* Document-const: RTLD_NOW
*
* rtld Fiddle::Handle flag.
*
* If this value is specified or the environment variable LD_BIND_NOW is
* set to a nonempty string, all undefined symbols in the library are
* resolved before Fiddle.dlopen returns. If this cannot be done an error
* is returned.
*/
rb_define_const(rb_cHandle, "RTLD_NOW", INT2NUM(RTLD_NOW));
rb_define_method(rb_cHandle, "initialize", rb_fiddle_handle_initialize, -1);
rb_define_method(rb_cHandle, "to_i", rb_fiddle_handle_to_i, 0);
rb_define_method(rb_cHandle, "close", rb_fiddle_handle_close, 0);
rb_define_method(rb_cHandle, "sym", rb_fiddle_handle_sym, 1);
rb_define_method(rb_cHandle, "[]", rb_fiddle_handle_sym, 1);
rb_define_method(rb_cHandle, "disable_close", rb_fiddle_handle_disable_close, 0);
rb_define_method(rb_cHandle, "enable_close", rb_fiddle_handle_enable_close, 0);
rb_define_method(rb_cHandle, "close_enabled?", rb_fiddle_handle_close_enabled_p, 0);
}
/* vim: set noet sws=4 sw=4: */