src/util/uFcontext.h

   1 #ifndef CMK_FCONTEXT_H
   2 #define CMK_FCONTEXT_H
   3
   4 #ifdef __cplusplus
   5 extern "C" {
   6 #endif
   7   typedef void * fcontext_t;
   8
   9   typedef struct uFcontext_stack_t {
  10     void *ss_sp;
  11     int ss_flags;
  12     size_t ss_size;
  13   } uFcontext_stack_t;
  14
  15   typedef struct transfer_t {
  16     fcontext_t fctx;
  17     void * data;
  18   } transfer_t;
  19
  20   extern void CthStartThread(transfer_t);
  21   typedef void (*uFcontext_fn_t)(transfer_t);
  22
  23   typedef struct data_t {
  24     void * from;
  25     void * data;
  26   } data_t;
  27
  28   typedef struct uFcontext_t {
  29     fcontext_t fctx;
  30     void (* func)(void *);
  31     uFcontext_stack_t uc_stack;
  32     struct uFcontext_t *uc_link;
  33     void *arg;
  34     data_t param;
  35   } uFcontext_t;
  36
  37   transfer_t jump_fcontext(fcontext_t const to, void *vp);
  38   fcontext_t make_fcontext(void *sp, size_t size, void (*fn)(transfer_t));
  39   transfer_t ontop_fcontext(fcontext_t const to, void *vp, transfer_t (*fn)(transfer_t));
  40
  41 /* Get user context and store it in variable pointed to by UCP.  */
  42   extern int getJcontext (uFcontext_t *__ucp);
  43
  44 /* Set user context from information of variable pointed to by UCP.  */
  45   extern int setJcontext (uFcontext_t *__ucp);
  46
  47 /* Save current context in context variable pointed to by OUCP and set
  48    context from variable pointed to by UCP.  */
  49   extern int swapJcontext (uFcontext_t *__oucp, uFcontext_t *__ucp);
  50
  51   extern void makeJcontext(uFcontext_t *__ucp, uFcontext_fn_t, void (*fn)(void*), void *arg);
  52 /* To keep the interface of uFcontext the same as the ucontext and uJcontext*/
  53   int getJcontext (uFcontext_t *__ucp) {
  54     return 0;
  55   }
  56
  57   int setJcontext (uFcontext_t *__ucp) {
  58     return swapJcontext(NULL, __ucp);
  59   }
  60
  61   void makeJcontext (uFcontext_t *__ucp, uFcontext_fn_t __func, void (*fn)(void *), void *arg) {
  62     __ucp->arg = arg;
  63     __ucp->uc_link = NULL;
  64     __ucp->func = fn;
  65     fcontext_t t = make_fcontext(__ucp->uc_stack.ss_sp, __ucp->uc_stack.ss_size, __func);
  66     __ucp->fctx = t;
  67   }
  68
  69   int swapJcontext(uFcontext_t *old_ucp,  uFcontext_t *new_ucp) {
  70      new_ucp->param.from = old_ucp;
  71      new_ucp->param.data = new_ucp;
  72      transfer_t t = jump_fcontext(new_ucp->fctx, &(new_ucp->param));
  73      data_t *old_data = (data_t *)t.data;
  74      uFcontext_t *prev_ucp = (uFcontext_t *)old_data->from;
  75      if (prev_ucp)
  76        prev_ucp->fctx = t.fctx;
  77      return 0;
  78   }
  79 #ifdef __cplusplus
  80 }
  81 #endif
  82 #endif