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The Ring programming language version 1.5.3 book - Part 92 of 184
1. Ring Documentation, Release 1.5.3
71.16 Threads Support
Next, another part of the configutaiton file, it’s important because we can learn from it how to add threads to our Ring
applications by using a threads library.
The idea is using ring_vm_mutexfunctions() and ring_vm_runcodefromthread() to execute Ring code.
<comment>
Threads
</comment>
<code>
void *al_func_thread(ALLEGRO_THREAD *thread, void *pPointer)
{
List *pList;
VM *pVM;
const char *cStr;
pList = (List *) pPointer ;
pVM = (VM *) ring_list_getpointer(pList,2);
cStr = ring_list_getstring(pList,1);
ring_vm_runcodefromthread(pVM,cStr);
ring_list_delete(pList);
return NULL;
}
RING_FUNC(ring_al_create_thread)
{
ALLEGRO_THREAD *pThread;
List *pList;
if ( RING_API_PARACOUNT != 1 ) {
RING_API_ERROR(RING_API_MISS1PARA);
return ;
}
if ( ! RING_API_ISSTRING(1) ) {
RING_API_ERROR(RING_API_BADPARATYPE);
return ;
}
pList = ring_list_new(0);
ring_list_addstring(pList,RING_API_GETSTRING(1));
ring_list_addpointer(pList,pPointer);
ring_vm_mutexfunctions((VM *) pPointer,al_create_mutex,
al_lock_mutex,al_unlock_mutex,al_destroy_mutex);
pThread = al_create_thread(al_func_thread, pList);
al_start_thread(pThread);
RING_API_RETCPOINTER(pThread,"ALLEGRO_THREAD");
}
RING_FUNC(ring_al_run_detached_thread)
{
List *pList;
if ( RING_API_PARACOUNT != 1 ) {
RING_API_ERROR(RING_API_MISS1PARA);
return ;
}
if ( ! RING_API_ISSTRING(1) ) {
71.16. Threads Support 785
2. Ring Documentation, Release 1.5.3
RING_API_ERROR(RING_API_BADPARATYPE);
return ;
}
pList = ring_list_new(0);
ring_list_addstring(pList,RING_API_GETSTRING(1));
ring_list_addpointer(pList,pPointer);
ring_vm_mutexfunctions((VM *) pPointer,al_create_mutex,
al_lock_mutex,al_unlock_mutex,al_destroy_mutex);
al_run_detached_thread(al_func_thread, pList);
}
</code>
<register>
ALLEGRO_THREAD *al_create_thread(void)
void al_run_detached_thread(void)
</register>
void al_start_thread(ALLEGRO_THREAD *thread)
void al_join_thread(ALLEGRO_THREAD *thread, void **ret_value)
void al_set_thread_should_stop(ALLEGRO_THREAD *thread)
bool al_get_thread_should_stop(ALLEGRO_THREAD *thread)
void al_destroy_thread(ALLEGRO_THREAD *thread)
ALLEGRO_MUTEX *al_create_mutex(void)
ALLEGRO_MUTEX *al_create_mutex_recursive(void)
void al_lock_mutex(ALLEGRO_MUTEX *mutex)
void al_unlock_mutex(ALLEGRO_MUTEX *mutex)
void al_destroy_mutex(ALLEGRO_MUTEX *mutex)
ALLEGRO_COND *al_create_cond(void)
void al_destroy_cond(ALLEGRO_COND *cond)
void al_wait_cond(ALLEGRO_COND *cond, ALLEGRO_MUTEX *mutex)
71.17 Code Generator Rules for Wrapping C++ Classes
• We can define classes between <class> and </class>
• Between <class> and <class> we set attributes like “name, nonew, para, parent, codename, passvmpointer and
abstract”
• we set the attributes using the style attributename:value or attributename only if no values are required
• The “name” attribute determine the class name in C++ code and this name will be the default name in the Ring
code
• The nonew instruction means that we don’t need new/delete methods
• The parent attribute determine the parent class name
• The codename attribute determine another class name in C++ code
• The passvmpoint instruction means passing the Ring VM pointer to the class constructor when we create new
objects, this happens when we set the codename attribute to a class the we will define and this class need the
Virtual Machine pointer (for example to use it to execute Ring code from C++ code).
• The abstract instruction means that no new method is required for this class “no objects will be created”.
• Using <nodllstartup> we can avoid #include “ring.h”, We need this to write our startup code.
• Using <libinitfunc> we can change the function name that register the library functions
• Using <ignorecpointertype> we can ignore pointer type check
71.17. Code Generator Rules for Wrapping C++ Classes 786
3. Ring Documentation, Release 1.5.3
• Using the aStringTypes list when can defined new types that treated like const char *
• Using the aBeforeReturn list when can define code that is inserted after the variable name when we return that
variable from a function
• Using the aNewMethodName list we can define another method name to be used in Ring code when we call
the C++ method. this feature is required because some C++ method may be identical to Ring Keywords like
“load”,”next”,”end” and “done”.
• in method prototype - when we use @ in the method name, we mean that we have the same method with different
parameters (As in C++)
71.18 Using configuration file that wrap C++ Library
To run the code generator to generate code for using C++ library in the Ring application, we can do that as we did
with using C libraries but here we will generate .cpp file instead of *.c file. Also we will determine another file to be
generated (.ring). This file will contains classes in Ring code that wraps C++ functions for using C++ classes and
objects.
ring parsec.ring qt.cf ring_qt.cpp ring_qt.ring
71.19 Configuration file for the Qt Framework
The next configuration file is used to wrap many Qt classes The configuration file is around 3500 lines and generate
C++ code around 56000 lines and generate also Ring code around 9000 lines.
<nodllstartup>
<libinitfunc> ring_qt_start
<ignorecpointertype>
<code>
extern "C" {
#include "ring.h"
}
#include "ring_qt.h"
#include "gpushbutton.h"
#include "gaction.h"
#include "glineedit.h"
#include "gtextedit.h"
#include "glistwidget.h"
#include "gtreeview.h"
#include "gtreewidget.h"
#include "gcombobox.h"
#include "gtabwidget.h"
#include "gtablewidget.h"
#include "gprogressbar.h"
#include "gspinbox.h"
#include "gslider.h"
#include "gdial.h"
#include "gwebview.h"
#include "gcheckbox.h"
71.18. Using configuration file that wrap C++ Library 787