regina/mt_notmt.h

   1 /* This is a stub file to support single-threading.
   2  * We need the following globals:
   3  *
   4  * 1) THREAD_PROTECT(varname)
   5  *    = a pseudo code NOT TERMINATED BY A SEMICOLON. After this point all
   6  *      code until a THREAD_UNPROTECT is executed by one thread at once.
   7  *      This may be done by a call to a semaphore action or something else.
   8  *      THREAD_PROTECT and THREAD_UNPROTECT define a C block logically.
   9  *      varname ist a variable created by PROTECTION_VAR()
  10  * 2) THREAD_UNPROTECT(varname)
  11  *    = see above
  12  * 3) PROTECTION_VAR(varname)
  13  *    = a pseudo code NOT TERMINATED BY A SEMICOLON. This define will
  14  *      create and initialize a local variable which may be used by
  15  *      THREAD_PROTECT and THREAD_UNPROTECT.
  16  *      Typical examples are the protection of static local variables.
  17  * 4) GLOBAL_PROTECTION_VAR(varname)
  18  *    = a pseudo code NOT TERMINATED BY A SEMICOLON. This define will
  19  *      create and initialize a global variable which may be used by
  20  *      THREAD_PROTECT and THREAD_UNPROTECT.
  21  *      Typical examples are the usage of the parser or global variables
  22  *      like macro_serialno.
  23  * 5) EXPORT_GLOBAL_PROTECTION_VAR(varname)
  24  *    = a pseudo code NOT TERMINATED BY A SEMICOLON. This define will
  25  *      export the varname in header files. There must exist one declaration
  26  *      of the variable done by GLOBAL_PROTECTION_VAR.
  27  * 6) GLOBAL_ENTRY_POINT()
  28  *    = initializes the process specific data and the thread specific data.
  29  *      This pseudo function is only called by those functions which are
  30  *      external (rexxsaa.h).
  31  *      It should return (tsd_t *) of the current thread.
  32  * 7) __regina_get_tsd()
  33  *    = pointer to a variable of type tsd_t.
  34  *      This may only exist after a GLOBAL_ENTRY_POINT()-call and must then
  35  *      exist.
  36  *
  37  */
  38
  39 #ifndef MT_H_INCLUDED
  40 #  error This file should included by mt.h, only.
  41 #endif
  42
  43 #define THREAD_PROTECT(varname)    {
  44 #define THREAD_UNPROTECT(varname)  }
  45 #define PROTECTION_VAR(varname)
  46 #define EXPORT_GLOBAL_PROTECTION_VAR(varname)
  47 #define GLOBAL_PROTECTION_VAR(varname)
  48
  49
  50 tsd_t *ReginaInitializeProcess(void);
  51 #define GLOBAL_ENTRY_POINT() ((__regina_tsd_initialized) ? &__regina_tsd : \
  52                                                   ReginaInitializeProcess() )
  53
  54 extern tsd_t __regina_tsd;
  55 extern int __regina_tsd_initialized; /* We are single-threaded -> allowed! */
  56
  57 /* we need a pointer to tsd_t sometimes: */
  58 #define __regina_get_tsd() (&__regina_tsd)
  59
  60 /* NEVER USE __regina_get_tsd() IF YOU CAN GET THE VALUE FROM SOMEWHERE ELSE.
  61  * IT REDUCES THE EXECUTION SPEED SIGNIFICANTLY. TAKE THE VALUE FROM THE CALLER
  62  * WHERE IT IS POSSIBLE.
  63  */
  64
  65 #ifdef TRACK_TSD_USAGE
  66 tsd_t *__regina_WorkHeavy(void);
  67 # undef __regina_get_tsd
  68 # define __regina_get_tsd() __regina_WorkHeavy()
  69 #endif