]> granicus.if.org Git - python/commitdiff
Patch #957398: Add public API for Generator Object/Type.
authorMartin v. Löwis <martin@v.loewis.de>
Tue, 1 Jun 2004 15:22:42 +0000 (15:22 +0000)
committerMartin v. Löwis <martin@v.loewis.de>
Tue, 1 Jun 2004 15:22:42 +0000 (15:22 +0000)
Doc/api/concrete.tex
Include/ceval.h
Include/genobject.h [new file with mode: 0644]
Makefile.pre.in
Misc/NEWS
Objects/genobject.c [new file with mode: 0644]
Python/ceval.c

index e60252878c45f2cff6f807971d8ae5e06609745c..62084bd699922e2ccf92af02cdd9774d48a12a53 100644 (file)
@@ -2603,3 +2603,34 @@ when accessed.  Cell objects are not likely to be useful elsewhere.
   reference counts are adjusted, and no checks are made for safety;
   \var{cell} must be non-\NULL{} and must be a cell object.
 \end{cfuncdesc}
+
+
+\subsection{Generator Objects \label{gen-objects}}
+
+Generator objects are what Python uses to implement generator iterators.
+They are normally created by iterating over a function that yields values,
+rather than explicitly calling \cfunction{PyGen_New}.
+
+\begin{ctypedesc}{PyGenObject}
+  The C structure used for generator objects.
+\end{ctypedesc}
+
+\begin{cvardesc}{PyTypeObject}{PyGen_Type}
+  The type object corresponding to generator objects
+\end{cvardesc}
+
+\begin{cfuncdesc}{int}{PyGen_Check}{ob}
+  Return true if \var{ob} is a generator object; \var{ob} must not be
+  \NULL.
+\end{cfuncdesc}
+
+\begin{cfuncdesc}{int}{PyGen_CheckExact}{ob}
+  Return true if \var{ob}'s type is \var{PyGen_Type}
+  is a generator object; \var{ob} must not be
+  \NULL.
+\end{cfuncdesc}
+
+\begin{cfuncdesc}{PyObject*}{PyGen_New}{PyFrameObject *frame}
+  Create and return a new generator object based on the \var{frame} object.
+  The parameter must not be \NULL.
+\end{cfuncdesc}
index dc3864b8eb3dbf0ef37c495de51a67a834d255a7..ae6de3a2856697d08d28668574b6944c7c128031 100644 (file)
@@ -64,6 +64,7 @@ PyAPI_FUNC(char *) PyEval_GetFuncName(PyObject *);
 PyAPI_FUNC(char *) PyEval_GetFuncDesc(PyObject *);
 
 PyAPI_FUNC(PyObject *) PyEval_GetCallStats(PyObject *);
+PyAPI_FUNC(PyObject *) PyEval_EvaluateFrame(PyObject *);
 
 /* this used to be handled on a per-thread basis - now just two globals */
 PyAPI_DATA(volatile int) _Py_Ticker;
diff --git a/Include/genobject.h b/Include/genobject.h
new file mode 100644 (file)
index 0000000..c9b7c19
--- /dev/null
@@ -0,0 +1,33 @@
+
+/* Generator object interface */
+
+#ifndef Py_GENOBJECT_H
+#define Py_GENOBJECT_H
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+       PyObject_HEAD
+       /* The gi_ prefix is intended to remind of generator-iterator. */
+
+       PyFrameObject *gi_frame;
+
+       /* True if generator is being executed. */
+       int gi_running;
+
+       /* List of weak reference. */
+       PyObject *gi_weakreflist;
+} PyGenObject;
+
+PyAPI_DATA(PyTypeObject) PyGen_Type;
+
+#define PyGen_Check(op) PyObject_TypeCheck(op, &PyGen_Type)
+#define PyGen_CheckExact(op) ((op)->ob_type == &PyGen_Type)
+
+PyAPI_FUNC(PyObject *) PyGen_New(PyFrameObject *);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* !Py_GENOBJECT_H */
index 9a5003998e0912bafbde4bc2aec56279e54b835a..074fba464ee17ec67ec1ea6314ce9bf153105eca 100644 (file)
@@ -261,6 +261,7 @@ OBJECT_OBJS=        \
                Objects/complexobject.o \
                Objects/descrobject.o \
                Objects/enumobject.o \
+               Objects/genobject.o \
                Objects/fileobject.o \
                Objects/floatobject.o \
                Objects/frameobject.o \
@@ -478,6 +479,7 @@ PYTHON_HEADERS= \
                Include/descrobject.h \
                Include/dictobject.h \
                Include/enumobject.h \
+               Include/genobject.h \
                Include/fileobject.h \
                Include/floatobject.h \
                Include/funcobject.h \
index 2c5dfd9b95f04f5fcc68afba52376a7c8f2f49e3..33bfc43cecd439dcb3e11a4ca82a47967dc646fc 100644 (file)
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -497,6 +497,9 @@ Build
 C API
 -----
 
+- New public functions PyEval_EvaluateFrame and PyGen_New to expose
+  generator objects.
+
 - New public functions Py_IncRef() and Py_DecRef(), exposing the
   functionality of the Py_XINCREF() and Py_XDECREF macros. Useful for
   runtime dynamic embedding of Python.  See patch #938302, by Bob
diff --git a/Objects/genobject.c b/Objects/genobject.c
new file mode 100644 (file)
index 0000000..0f7373a
--- /dev/null
@@ -0,0 +1,129 @@
+/* Generator object implementation */
+
+#include "Python.h"
+#include "frameobject.h"
+#include "genobject.h"
+#include "ceval.h"
+#include "structmember.h"
+
+static int
+gen_traverse(PyGenObject *gen, visitproc visit, void *arg)
+{
+       return visit((PyObject *)gen->gi_frame, arg);
+}
+
+static void
+gen_dealloc(PyGenObject *gen)
+{
+       _PyObject_GC_UNTRACK(gen);
+       if (gen->gi_weakreflist != NULL)
+               PyObject_ClearWeakRefs((PyObject *) gen);
+       Py_DECREF(gen->gi_frame);
+       PyObject_GC_Del(gen);
+}
+
+static PyObject *
+gen_iternext(PyGenObject *gen)
+{
+       PyThreadState *tstate = PyThreadState_GET();
+       PyFrameObject *f = gen->gi_frame;
+       PyObject *result;
+
+       if (gen->gi_running) {
+               PyErr_SetString(PyExc_ValueError,
+                               "generator already executing");
+               return NULL;
+       }
+       if (f->f_stacktop == NULL)
+               return NULL;
+
+       /* Generators always return to their most recent caller, not
+        * necessarily their creator. */
+       Py_XINCREF(tstate->frame);
+       assert(f->f_back == NULL);
+       f->f_back = tstate->frame;
+
+       gen->gi_running = 1;
+       result = PyEval_EvaluateFrame((PyObject *)f);
+       gen->gi_running = 0;
+
+       /* Don't keep the reference to f_back any longer than necessary.  It
+        * may keep a chain of frames alive or it could create a reference
+        * cycle. */
+       Py_XDECREF(f->f_back);
+       f->f_back = NULL;
+
+       /* If the generator just returned (as opposed to yielding), signal
+        * that the generator is exhausted. */
+       if (result == Py_None && f->f_stacktop == NULL) {
+               Py_DECREF(result);
+               result = NULL;
+       }
+
+       return result;
+}
+
+static PyObject *
+gen_getiter(PyObject *gen)
+{
+       Py_INCREF(gen);
+       return gen;
+}
+
+static PyMemberDef gen_memberlist[] = {
+       {"gi_frame",    T_OBJECT, offsetof(PyGenObject, gi_frame),      RO},
+       {"gi_running",  T_INT,    offsetof(PyGenObject, gi_running),    RO},
+       {NULL}  /* Sentinel */
+};
+
+PyTypeObject PyGen_Type = {
+       PyObject_HEAD_INIT(&PyType_Type)
+       0,                                      /* ob_size */
+       "generator",                            /* tp_name */
+       sizeof(PyGenObject),                    /* tp_basicsize */
+       0,                                      /* tp_itemsize */
+       /* methods */
+       (destructor)gen_dealloc,                /* tp_dealloc */
+       0,                                      /* tp_print */
+       0,                                      /* tp_getattr */
+       0,                                      /* tp_setattr */
+       0,                                      /* tp_compare */
+       0,                                      /* tp_repr */
+       0,                                      /* tp_as_number */
+       0,                                      /* tp_as_sequence */
+       0,                                      /* tp_as_mapping */
+       0,                                      /* tp_hash */
+       0,                                      /* tp_call */
+       0,                                      /* tp_str */
+       PyObject_GenericGetAttr,                /* tp_getattro */
+       0,                                      /* tp_setattro */
+       0,                                      /* tp_as_buffer */
+       Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
+       0,                                      /* tp_doc */
+       (traverseproc)gen_traverse,             /* tp_traverse */
+       0,                                      /* tp_clear */
+       0,                                      /* tp_richcompare */
+       offsetof(PyGenObject, gi_weakreflist),  /* tp_weaklistoffset */
+       (getiterfunc)gen_getiter,               /* tp_iter */
+       (iternextfunc)gen_iternext,             /* tp_iternext */
+       0,                                      /* tp_methods */
+       gen_memberlist,                         /* tp_members */
+       0,                                      /* tp_getset */
+       0,                                      /* tp_base */
+       0,                                      /* tp_dict */
+};
+
+PyObject *
+PyGen_New(PyFrameObject *f)
+{
+       PyGenObject *gen = PyObject_GC_New(PyGenObject, &PyGen_Type);
+       if (gen == NULL) {
+               Py_DECREF(f);
+               return NULL;
+       }
+       gen->gi_frame = f;
+       gen->gi_running = 0;
+       gen->gi_weakreflist = NULL;
+       _PyObject_GC_TRACK(gen);
+       return (PyObject *)gen;
+}
index c103f1433947cf057e32dfed0f1cbe4cc2db139f..2cebf44a4c971214f7c9e73177aef71dbf35e9b2 100644 (file)
@@ -10,6 +10,7 @@
 
 #include "compile.h"
 #include "frameobject.h"
+#include "genobject.h"
 #include "eval.h"
 #include "opcode.h"
 #include "structmember.h"
@@ -139,143 +140,6 @@ PyEval_GetCallStats(PyObject *self)
 }
 #endif
 
-static PyTypeObject gentype;
-
-typedef struct {
-       PyObject_HEAD
-       /* The gi_ prefix is intended to remind of generator-iterator. */
-
-       PyFrameObject *gi_frame;
-
-       /* True if generator is being executed. */
-       int gi_running;
-
-       /* List of weak reference. */
-       PyObject *gi_weakreflist;
-} genobject;
-
-static PyObject *
-gen_new(PyFrameObject *f)
-{
-       genobject *gen = PyObject_GC_New(genobject, &gentype);
-       if (gen == NULL) {
-               Py_DECREF(f);
-               return NULL;
-       }
-       gen->gi_frame = f;
-       gen->gi_running = 0;
-       gen->gi_weakreflist = NULL;
-       _PyObject_GC_TRACK(gen);
-       return (PyObject *)gen;
-}
-
-static int
-gen_traverse(genobject *gen, visitproc visit, void *arg)
-{
-       return visit((PyObject *)gen->gi_frame, arg);
-}
-
-static void
-gen_dealloc(genobject *gen)
-{
-       _PyObject_GC_UNTRACK(gen);
-       if (gen->gi_weakreflist != NULL)
-               PyObject_ClearWeakRefs((PyObject *) gen);
-       Py_DECREF(gen->gi_frame);
-       PyObject_GC_Del(gen);
-}
-
-static PyObject *
-gen_iternext(genobject *gen)
-{
-       PyThreadState *tstate = PyThreadState_GET();
-       PyFrameObject *f = gen->gi_frame;
-       PyObject *result;
-
-       if (gen->gi_running) {
-               PyErr_SetString(PyExc_ValueError,
-                               "generator already executing");
-               return NULL;
-       }
-       if (f->f_stacktop == NULL)
-               return NULL;
-
-       /* Generators always return to their most recent caller, not
-        * necessarily their creator. */
-       Py_XINCREF(tstate->frame);
-       assert(f->f_back == NULL);
-       f->f_back = tstate->frame;
-
-       gen->gi_running = 1;
-       result = eval_frame(f);
-       gen->gi_running = 0;
-
-       /* Don't keep the reference to f_back any longer than necessary.  It
-        * may keep a chain of frames alive or it could create a reference
-        * cycle. */
-       Py_XDECREF(f->f_back);
-       f->f_back = NULL;
-
-       /* If the generator just returned (as opposed to yielding), signal
-        * that the generator is exhausted. */
-       if (result == Py_None && f->f_stacktop == NULL) {
-               Py_DECREF(result);
-               result = NULL;
-       }
-
-       return result;
-}
-
-static PyObject *
-gen_getiter(PyObject *gen)
-{
-       Py_INCREF(gen);
-       return gen;
-}
-
-static PyMemberDef gen_memberlist[] = {
-       {"gi_frame",    T_OBJECT, offsetof(genobject, gi_frame),        RO},
-       {"gi_running",  T_INT,    offsetof(genobject, gi_running),      RO},
-       {NULL}  /* Sentinel */
-};
-
-static PyTypeObject gentype = {
-       PyObject_HEAD_INIT(&PyType_Type)
-       0,                                      /* ob_size */
-       "generator",                            /* tp_name */
-       sizeof(genobject),                      /* tp_basicsize */
-       0,                                      /* tp_itemsize */
-       /* methods */
-       (destructor)gen_dealloc,                /* tp_dealloc */
-       0,                                      /* tp_print */
-       0,                                      /* tp_getattr */
-       0,                                      /* tp_setattr */
-       0,                                      /* tp_compare */
-       0,                                      /* tp_repr */
-       0,                                      /* tp_as_number */
-       0,                                      /* tp_as_sequence */
-       0,                                      /* tp_as_mapping */
-       0,                                      /* tp_hash */
-       0,                                      /* tp_call */
-       0,                                      /* tp_str */
-       PyObject_GenericGetAttr,                /* tp_getattro */
-       0,                                      /* tp_setattro */
-       0,                                      /* tp_as_buffer */
-       Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
-       0,                                      /* tp_doc */
-       (traverseproc)gen_traverse,             /* tp_traverse */
-       0,                                      /* tp_clear */
-       0,                                      /* tp_richcompare */
-       offsetof(genobject, gi_weakreflist),    /* tp_weaklistoffset */
-       (getiterfunc)gen_getiter,               /* tp_iter */
-       (iternextfunc)gen_iternext,             /* tp_iternext */
-       0,                                      /* tp_methods */
-       gen_memberlist,                         /* tp_members */
-       0,                                      /* tp_getset */
-       0,                                      /* tp_base */
-       0,                                      /* tp_dict */
-};
-
 
 #ifdef WITH_THREAD
 
@@ -2673,7 +2537,7 @@ PyEval_EvalCodeEx(PyCodeObject *co, PyObject *globals, PyObject *locals,
 
                /* Create a new generator that owns the ready to run frame
                 * and return that as the value. */
-               return gen_new(f);
+               return PyGen_New(f);
        }
 
         retval = eval_frame(f);
@@ -3407,6 +3271,12 @@ PyEval_GetFuncDesc(PyObject *func)
        }
 }
 
+PyObject *
+PyEval_EvaluateFrame(PyObject *fo)
+{
+       return eval_frame((PyFrameObject *)fo);
+}
+
 #define EXT_POP(STACK_POINTER) (*--(STACK_POINTER))
 
 static void