Include/pystate.h

   1
   2 /* Thread and interpreter state structures and their interfaces */
   3
   4
   5 #ifndef Py_PYSTATE_H
   6 #define Py_PYSTATE_H
   7 #ifdef __cplusplus
   8 extern "C" {
   9 #endif
  10
  11 /* State shared between threads */
  12
  13 struct _ts; /* Forward */
  14 struct _is; /* Forward */
  15
  16 typedef struct _is {
  17
  18     struct _is *next;
  19     struct _ts *tstate_head;
  20
  21     PyObject *modules;
  22     PyObject *sysdict;
  23     PyObject *builtins;
  24     PyObject *modules_reloading;
  25
  26     PyObject *codec_search_path;
  27     PyObject *codec_search_cache;
  28     PyObject *codec_error_registry;
  29
  30 #ifdef HAVE_DLOPEN
  31     int dlopenflags;
  32 #endif
  33 #ifdef WITH_TSC
  34     int tscdump;
  35 #endif
  36
  37 } PyInterpreterState;
  38
  39
  40 /* State unique per thread */
  41
  42 struct _frame; /* Avoid including frameobject.h */
  43
  44 /* Py_tracefunc return -1 when raising an exception, or 0 for success. */
  45 typedef int (*Py_tracefunc)(PyObject *, struct _frame *, int, PyObject *);
  46
  47 /* The following values are used for 'what' for tracefunc functions: */
  48 #define PyTrace_CALL 0
  49 #define PyTrace_EXCEPTION 1
  50 #define PyTrace_LINE 2
  51 #define PyTrace_RETURN 3
  52 #define PyTrace_C_CALL 4
  53 #define PyTrace_C_EXCEPTION 5
  54 #define PyTrace_C_RETURN 6
  55
  56 typedef struct _ts {
  57     /* See Python/ceval.c for comments explaining most fields */
  58
  59     struct _ts *next;
  60     PyInterpreterState *interp;
  61
  62     struct _frame *frame;
  63     int recursion_depth;
  64     /* 'tracing' keeps track of the execution depth when tracing/profiling.
  65        This is to prevent the actual trace/profile code from being recorded in
  66        the trace/profile. */
  67     int tracing;
  68     int use_tracing;
  69
  70     Py_tracefunc c_profilefunc;
  71     Py_tracefunc c_tracefunc;
  72     PyObject *c_profileobj;
  73     PyObject *c_traceobj;
  74
  75     PyObject *curexc_type;
  76     PyObject *curexc_value;
  77     PyObject *curexc_traceback;
  78
  79     PyObject *exc_type;
  80     PyObject *exc_value;
  81     PyObject *exc_traceback;
  82
  83     PyObject *dict;  /* Stores per-thread state */
  84
  85     /* tick_counter is incremented whenever the check_interval ticker
  86      * reaches zero. The purpose is to give a useful measure of the number
  87      * of interpreted bytecode instructions in a given thread.  This
  88      * extremely lightweight statistic collector may be of interest to
  89      * profilers (like psyco.jit()), although nothing in the core uses it.
  90      */
  91     int tick_counter;
  92
  93     int gilstate_counter;
  94
  95     PyObject *async_exc; /* Asynchronous exception to raise */
  96     long thread_id; /* Thread id where this tstate was created */
  97
  98     /* XXX signal handlers should also be here */
  99
 100 } PyThreadState;
 101
 102
 103 PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_New(void);
 104 PyAPI_FUNC(void) PyInterpreterState_Clear(PyInterpreterState *);
 105 PyAPI_FUNC(void) PyInterpreterState_Delete(PyInterpreterState *);
 106
 107 PyAPI_FUNC(PyThreadState *) PyThreadState_New(PyInterpreterState *);
 108 PyAPI_FUNC(void) PyThreadState_Clear(PyThreadState *);
 109 PyAPI_FUNC(void) PyThreadState_Delete(PyThreadState *);
 110 #ifdef WITH_THREAD
 111 PyAPI_FUNC(void) PyThreadState_DeleteCurrent(void);
 112 #endif
 113
 114 PyAPI_FUNC(PyThreadState *) PyThreadState_Get(void);
 115 PyAPI_FUNC(PyThreadState *) PyThreadState_Swap(PyThreadState *);
 116 PyAPI_FUNC(PyObject *) PyThreadState_GetDict(void);
 117 PyAPI_FUNC(int) PyThreadState_SetAsyncExc(long, PyObject *);
 118
 119
 120 /* Variable and macro for in-line access to current thread state */
 121
 122 PyAPI_DATA(PyThreadState *) _PyThreadState_Current;
 123
 124 #ifdef Py_DEBUG
 125 #define PyThreadState_GET() PyThreadState_Get()
 126 #else
 127 #define PyThreadState_GET() (_PyThreadState_Current)
 128 #endif
 129
 130 typedef
 131     enum {PyGILState_LOCKED, PyGILState_UNLOCKED}
 132         PyGILState_STATE;
 133
 134 /* Ensure that the current thread is ready to call the Python
 135    C API, regardless of the current state of Python, or of its
 136    thread lock.  This may be called as many times as desired
 137    by a thread so long as each call is matched with a call to
 138    PyGILState_Release().  In general, other thread-state APIs may
 139    be used between _Ensure() and _Release() calls, so long as the
 140    thread-state is restored to its previous state before the Release().
 141    For example, normal use of the Py_BEGIN_ALLOW_THREADS/
 142    Py_END_ALLOW_THREADS macros are acceptable.
 143
 144    The return value is an opaque "handle" to the thread state when
 145    PyGILState_Ensure() was called, and must be passed to
 146    PyGILState_Release() to ensure Python is left in the same state. Even
 147    though recursive calls are allowed, these handles can *not* be shared -
 148    each unique call to PyGILState_Ensure must save the handle for its
 149    call to PyGILState_Release.
 150
 151    When the function returns, the current thread will hold the GIL.
 152
 153    Failure is a fatal error.
 154 */
 155 PyAPI_FUNC(PyGILState_STATE) PyGILState_Ensure(void);
 156
 157 /* Release any resources previously acquired.  After this call, Python's
 158    state will be the same as it was prior to the corresponding
 159    PyGILState_Ensure() call (but generally this state will be unknown to
 160    the caller, hence the use of the GILState API.)
 161
 162    Every call to PyGILState_Ensure must be matched by a call to
 163    PyGILState_Release on the same thread.
 164 */
 165 PyAPI_FUNC(void) PyGILState_Release(PyGILState_STATE);
 166
 167 /* Helper/diagnostic function - get the current thread state for
 168    this thread.  May return NULL if no GILState API has been used
 169    on the current thread.  Note the main thread always has such a
 170    thread-state, even if no auto-thread-state call has been made
 171    on the main thread.
 172 */
 173 PyAPI_FUNC(PyThreadState *) PyGILState_GetThisThreadState(void);
 174
 175 /* The implementation of sys._current_frames()  Returns a dict mapping
 176    thread id to that thread's current frame.
 177 */
 178 PyAPI_FUNC(PyObject *) _PyThread_CurrentFrames(void);
 179
 180 /* Routines for advanced debuggers, requested by David Beazley.
 181    Don't use unless you know what you are doing! */
 182 PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Head(void);
 183 PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Next(PyInterpreterState *);
 184 PyAPI_FUNC(PyThreadState *) PyInterpreterState_ThreadHead(PyInterpreterState *);
 185 PyAPI_FUNC(PyThreadState *) PyThreadState_Next(PyThreadState *);
 186
 187 typedef struct _frame *(*PyThreadFrameGetter)(PyThreadState *self_);
 188
 189 /* hook for PyEval_GetFrame(), requested for Psyco */
 190 PyAPI_DATA(PyThreadFrameGetter) _PyThreadState_GetFrame;
 191
 192 #ifdef __cplusplus
 193 }
 194 #endif
 195 #endif /* !Py_PYSTATE_H */