#include "gras_config.h"
XBT_LOG_NEW_DEFAULT_SUBCATEGORY(context, xbt, "Context");
+/* #define WARNING(format, ...) (fprintf(stderr, "[%s , %s : %d] ", __FILE__, __FUNCTION__, __LINE__),\ */
+/* fprintf(stderr, format, ## __VA_ARGS__), \ */
+/* fprintf(stderr, "\n")) */
+/* #define VOIRP(expr) WARNING(" {" #expr " = %p }", expr) */
+
#ifndef HAVE_UCONTEXT_H
/* don't want to play with conditional compilation in automake tonight, sorry.
include directly the c file from here when needed. */
#endif
static xbt_context_t current_context = NULL;
-static xbt_dynar_t context_to_destroy = NULL;
+static xbt_context_t init_context = NULL;
+static xbt_swag_t context_to_destroy = NULL;
+static xbt_swag_t context_living = NULL;
-void context_init(void)
+static void __xbt_context_yield(xbt_context_t context)
+{
+ int return_value = 0;
+
+ xbt_assert0(current_context,"You have to call context_init() first.");
+
+/* WARNING("--------- current_context (%p) is yielding to context(%p) ---------",current_context,context); */
+/* VOIRP(current_context); */
+/* if(current_context) VOIRP(current_context->save); */
+/* VOIRP(context); */
+/* if(context) VOIRP(context->save); */
+
+ if (context) {
+ if(context->save==NULL) {
+/* WARNING("**** Yielding to somebody else ****"); */
+/* WARNING("Saving current_context value (%p) to context(%p)->save",current_context,context); */
+ context->save = current_context ;
+/* WARNING("current_context becomes context(%p) ",context); */
+ current_context = context ;
+/* WARNING("Current position memorized (context->save). Jumping to context (%p)",context); */
+ return_value = swapcontext (&(context->save->uc), &(context->uc));
+ xbt_assert0((return_value==0),"Context swapping failure");
+/* WARNING("I am (%p). Coming back\n",context); */
+ } else {
+ xbt_context_t old_context = context->save ;
+/* WARNING("**** Back ! ****"); */
+/* WARNING("Setting current_context (%p) to context(%p)->save",current_context,context); */
+ current_context = context->save ;
+/* WARNING("Setting context(%p)->save to NULL",context); */
+ context->save = NULL ;
+/* WARNING("Current position memorized (%p). Jumping to context (%p)",context,old_context); */
+ return_value = swapcontext (&(context->uc), &(old_context->uc));
+ xbt_assert0((return_value==0),"Context swapping failure");
+/* WARNING("I am (%p). Coming back\n",context); */
+ }
+ }
+
+ return;
+}
+
+static void xbt_context_destroy(xbt_context_t context)
+{
+ xbt_free(context);
+
+ return;
+}
+
+/** \name Functions
+ * \ingroup XBT_context
+ */
+/*@{*/
+/** Context module initialization
+ *
+ * \warning It has to be called before using any other function of this module.
+ */
+void xbt_context_init(void)
{
if(!current_context) {
- current_context = xbt_new0(s_xbt_context_t,1);
- context_to_destroy = xbt_dynar_new(sizeof(xbt_context_t),xbt_free);
+ current_context = init_context = xbt_new0(s_xbt_context_t,1);
+ context_to_destroy = xbt_swag_new(xbt_swag_offset(*current_context,hookup));
+ context_living = xbt_swag_new(xbt_swag_offset(*current_context,hookup));
+ xbt_swag_insert(init_context, context_living);
}
}
-void context_empty_trash(void)
+/** Garbage collection
+ *
+ * Should be called some time to time to free the memory allocated for contexts
+ * that have finished executing their main functions.
+ */
+void xbt_context_empty_trash(void)
{
- xbt_dynar_reset(context_to_destroy);
+ xbt_context_t context=NULL;
+
+ while((context=xbt_swag_extract(context_to_destroy)))
+ xbt_context_destroy(context);
}
static void *__context_wrapper(void *c)
/* msg_global->current_process = process; */
+ if(context->startup_func)
+ context->startup_func(context->startup_arg);
+
/* WARNING("Calling the main function"); */
+ /* xbt_context_yield(context); */
(context->code) (context->argc,context->argv);
for(i=0;i<context->argc; i++)
if(context->argv[i]) xbt_free(context->argv[i]);
if(context->argv) xbt_free(context->argv);
- xbt_dynar_push(context_to_destroy, &context);
+ if(context->cleanup_func)
+ context->cleanup_func(context->cleanup_arg);
- context_yield(context);
+ xbt_swag_remove(context, context_living);
+ xbt_swag_insert(context, context_to_destroy);
+ __xbt_context_yield(context);
+ xbt_assert0(0,"You're cannot be here!");
return NULL;
}
-void context_start(xbt_context_t context)
+/**
+ * \param context the context to start
+ *
+ * Calling this function prepares \a context to be run. It will
+ however run effectively only when calling #xbt_context_schedule
+ */
+void xbt_context_start(xbt_context_t context)
{
+/* xbt_fifo_insert(msg_global->process, process); */
+/* xbt_fifo_insert(msg_global->process_to_run, process); */
-/* TBX_FIFO_insert(msg_global->process, process); */
-/* TBX_FIFO_insert(msg_global->process_to_run, process); */
-
- /* WARNING("Assigning __MSG_process_launcher to context (%p)",context); */
makecontext (&(context->uc), (void (*) (void)) __context_wrapper,
1, context);
-
return;
}
-xbt_context_t context_create(xbt_context_function_t code,
- int argc, char *argv[])
+/**
+ * \param code a main function
+ * \param startup_func a function to call when running the context for
+ * the first time and just before the main function \a code
+ * \param startup_arg the argument passed to the previous function (\a startup_func)
+ * \param cleanup_func a function to call when running the context, just after
+ the termination of the main function \a code
+ * \param cleanup_arg the argument passed to the previous function (\a cleanup_func)
+ * \param argc first argument of function \a code
+ * \param argv seconde argument of function \a code
+ */
+xbt_context_t xbt_context_new(xbt_context_function_t code,
+ void_f_pvoid_t startup_func, void *startup_arg,
+ void_f_pvoid_t cleanup_func, void *cleanup_arg,
+ int argc, char *argv[])
{
xbt_context_t res = NULL;
res = xbt_new0(s_xbt_context_t,1);
- /* WARNING("Initializing context (%p)",res); */
+ /* FIXME: strerror is not thread safe */
+ xbt_assert2(getcontext(&(res->uc))==0,"Error in context saving: %d (%s)", errno, strerror(errno));
- xbt_assert0(getcontext(&(res->uc))==0,"Error in context saving.");
-
- /* VOIRP(res->uc); */
res->code = code;
- res->uc.uc_link = &(current_context->uc); /* FIXME LATER */
+ res->uc.uc_link = NULL;
+ res->argc = argc;
+ res->argv = argv;
+/* res->uc.uc_link = &(current_context->uc); */
/* WARNING : when this context is over, the current_context (i.e. the
- father), is awaken... May result in bugs later.*/
+ father), is awaken... Theorically, the wrapper should prevent using
+ this feature. */
res->uc.uc_stack.ss_sp = res->stack;
res->uc.uc_stack.ss_size = STACK_SIZE;
+ res->startup_func = startup_func;
+ res->startup_arg = startup_arg;
+ res->cleanup_func = cleanup_func;
+ res->cleanup_arg = cleanup_arg;
+
+ xbt_swag_insert(res, context_living);
+
return res;
}
-static void context_destroy(xbt_context_t context)
-{
- xbt_free(context);
- return;
+/**
+ * Calling this function makes the current context yield. The context
+ * that scheduled it returns from xbt_context_schedule as if nothing
+ * had happened.
+ */
+void xbt_context_yield(void)
+{
+ __xbt_context_yield(current_context);
}
-void context_yield(xbt_context_t context)
+
+/**
+ * \param context the winner
+ *
+ * Calling this function blocks the current context and schedule \a context.
+ * When \a context will call xbt_context_yield, it will return
+ * to this function as if nothing had happened.
+ */
+void xbt_context_schedule(xbt_context_t context)
{
+ xbt_assert0((current_context==init_context),
+ "You are not supposed to run this function here!");
+ __xbt_context_yield(context);
+}
- xbt_assert0(current_context,"You have to call context_init() first.");
+/**
+ * This function kill all existing context and free all the memory
+ * that has been allocated in this module.
+ */
+void xbt_context_exit(void) {
+ xbt_context_t context=NULL;
- /* __MSG_context_init(); */
- /* fprintf(stderr,"\n"); */
- /* WARNING("--------- current_context (%p) is yielding to context(%p) ---------",current_context,context); */
- /* VOIRP(current_context); */
- /* if(current_context) VOIRP(current_context->save); */
- /* VOIRP(context); */
- /* if(context) VOIRP(context->save); */
+ xbt_context_empty_trash();
+ xbt_swag_free(context_to_destroy);
- if (context) {
-/* m_process_t self = msg_global->current_process; */
- if(context->save==NULL) {
- /* WARNING("**** Yielding to somebody else ****"); */
- /* WARNING("Saving current_context value (%p) to context(%p)->save",current_context,context); */
- context->save = current_context ;
- context->uc.uc_link = &(current_context->uc);
- /* WARNING("current_context becomes context(%p) ",context); */
- current_context = context ;
- /* WARNING("Current position memorized (context->save). Jumping to context (%p)",context); */
- if(!swapcontext (&(context->save->uc), &(context->uc)))
- xbt_assert0(0,"Context swapping failure");
- /* WARNING("I am (%p). Coming back\n",context); */
- } else {
- xbt_context_t old_context = context->save ;
- /* WARNING("**** Back ! ****"); */
- /* WARNING("Setting current_context (%p) to context(%p)->save",current_context,context); */
- current_context = context->save ;
- /* WARNING("Setting context(%p)->save to NULL",current_context,context); */
- context->save = NULL ;
- /* WARNING("Current position memorized (%p). Jumping to context (%p)",context,old_context); */
- if(!swapcontext (&(context->uc), &(old_context->uc)) )
- xbt_assert0(0,"Context swapping failure");
- /* WARNING("I am (%p). Coming back\n",context); */
- }
-/* msg_global->current_process = self; */
- }
+ while((context=xbt_swag_extract(context_living)))
+ xbt_context_free(context);
+
+ xbt_swag_free(context_living);
+
+ init_context = current_context = NULL ;
+}
+
+/**
+ * \param context poor victim
+ *
+ * This function simply kills \a context... scarry isn't it ?
+ */
+void xbt_context_free(xbt_context_t context)
+{
+ int i ;
+
+ xbt_swag_remove(context, context_living);
+ for(i=0;i<context->argc; i++)
+ if(context->argv[i]) xbt_free(context->argv[i]);
+ if(context->argv) xbt_free(context->argv);
+
+ if(context->cleanup_func)
+ context->cleanup_func(context->cleanup_arg);
+ xbt_context_destroy(context);
return;
}
+/*@}*/
