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diff --git a/Include/abstract.h b/Include/abstract.h new file mode 100644 index 0000000..8d8900b --- /dev/null +++ b/Include/abstract.h @@ -0,0 +1,810 @@ +#ifndef Py_ABSTRACTOBJECT_H +#define Py_ABSTRACTOBJECT_H +#ifdef __cplusplus +extern "C" { +#endif + +/*********************************************************** +Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam, +The Netherlands. + + All Rights Reserved + +Permission to use, copy, modify, and distribute this software and its +documentation for any purpose and without fee is hereby granted, +provided that the above copyright notice appear in all copies and that +both that copyright notice and this permission notice appear in +supporting documentation, and that the names of Stichting Mathematisch +Centrum or CWI not be used in advertising or publicity pertaining to +distribution of the software without specific, written prior permission. + +STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO +THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND +FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE +FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT +OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + +******************************************************************/ + +/* Abstract Object Interface (many thanks to Jim Fulton) */ + +/* + PROPOSAL: A Generic Python Object Interface for Python C Modules + +Problem + + Python modules written in C that must access Python objects must do + so through routines whose interfaces are described by a set of + include files. Unfortunately, these routines vary according to the + object accessed. To use these routines, the C programmer must check + the type of the object being used and must call a routine based on + the object type. For example, to access an element of a sequence, + the programmer must determine whether the sequence is a list or a + tuple: + + if(is_tupleobject(o)) + e=gettupleitem(o,i) + else if(is_listitem(o)) + e=getlistitem(o,i) + + If the programmer wants to get an item from another type of object + that provides sequence behavior, there is no clear way to do it + correctly. + + The persistent programmer may peruse object.h and find that the + _typeobject structure provides a means of invoking up to (currently + about) 41 special operators. So, for example, a routine can get an + item from any object that provides sequence behavior. However, to + use this mechanism, the programmer must make their code dependent on + the current Python implementation. + + Also, certain semantics, especially memory management semantics, may + differ by the type of object being used. Unfortunately, these + semantics are not clearly described in the current include files. + An abstract interface providing more consistent semantics is needed. + +Proposal + + I propose the creation of a standard interface (with an associated + library of routines and/or macros) for generically obtaining the + services of Python objects. This proposal can be viewed as one + components of a Python C interface consisting of several components. + + From the viewpoint of of C access to Python services, we have (as + suggested by Guido in off-line discussions): + + - "Very high level layer": two or three functions that let you exec or + eval arbitrary Python code given as a string in a module whose name is + given, passing C values in and getting C values out using + mkvalue/getargs style format strings. This does not require the user + to declare any variables of type "PyObject *". This should be enough + to write a simple application that gets Python code from the user, + execs it, and returns the output or errors. (Error handling must also + be part of this API.) + + - "Abstract objects layer": which is the subject of this proposal. + It has many functions operating on objects, and lest you do many + things from C that you can also write in Python, without going + through the Python parser. + + - "Concrete objects layer": This is the public type-dependent + interface provided by the standard built-in types, such as floats, + strings, and lists. This interface exists and is currently + documented by the collection of include files provides with the + Python distributions. + + From the point of view of Python accessing services provided by C + modules: + + - "Python module interface": this interface consist of the basic + routines used to define modules and their members. Most of the + current extensions-writing guide deals with this interface. + + - "Built-in object interface": this is the interface that a new + built-in type must provide and the mechanisms and rules that a + developer of a new built-in type must use and follow. + + This proposal is a "first-cut" that is intended to spur + discussion. See especially the lists of notes. + + The Python C object interface will provide four protocols: object, + numeric, sequence, and mapping. Each protocol consists of a + collection of related operations. If an operation that is not + provided by a particular type is invoked, then a standard exception, + NotImplementedError is raised with a operation name as an argument. + In addition, for convenience this interface defines a set of + constructors for building objects of built-in types. This is needed + so new objects can be returned from C functions that otherwise treat + objects generically. + +Memory Management + + For all of the functions described in this proposal, if a function + retains a reference to a Python object passed as an argument, then the + function will increase the reference count of the object. It is + unnecessary for the caller to increase the reference count of an + argument in anticipation of the object's retention. + + All Python objects returned from functions should be treated as new + objects. Functions that return objects assume that the caller will + retain a reference and the reference count of the object has already + been incremented to account for this fact. A caller that does not + retain a reference to an object that is returned from a function + must decrement the reference count of the object (using + DECREF(object)) to prevent memory leaks. + + Note that the behavior mentioned here is different from the current + behavior for some objects (e.g. lists and tuples) when certain + type-specific routines are called directly (e.g. setlistitem). The + proposed abstraction layer will provide a consistent memory + management interface, correcting for inconsistent behavior for some + built-in types. + +Protocols + +xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx*/ + +/* Object Protocol: */ + + /* Implemented elsewhere: + + int PyObject_Print(PyObject *o, FILE *fp, int flags); + + Print an object, o, on file, fp. Returns -1 on + error. The flags argument is used to enable certain printing + options. The only option currently supported is Py_Print_RAW. + + (What should be said about Py_Print_RAW?) + + */ + + /* Implemented elsewhere: + + int PyObject_HasAttrString(PyObject *o, char *attr_name); + + Returns 1 if o has the attribute attr_name, and 0 otherwise. + This is equivalent to the Python expression: + hasattr(o,attr_name). + + This function always succeeds. + + */ + + /* Implemented elsewhere: + + PyObject* PyObject_GetAttrString(PyObject *o, char *attr_name); + + Retrieve an attributed named attr_name form object o. + Returns the attribute value on success, or NULL on failure. + This is the equivalent of the Python expression: o.attr_name. + + */ + + /* Implemented elsewhere: + + int PyObject_HasAttr(PyObject *o, PyObject *attr_name); + + Returns 1 if o has the attribute attr_name, and 0 otherwise. + This is equivalent to the Python expression: + hasattr(o,attr_name). + + This function always succeeds. + + */ + + /* Implemented elsewhere: + + PyObject* PyObject_GetAttr(PyObject *o, PyObject *attr_name); + + Retrieve an attributed named attr_name form object o. + Returns the attribute value on success, or NULL on failure. + This is the equivalent of the Python expression: o.attr_name. + + */ + + + /* Implemented elsewhere: + + int PyObject_SetAttrString(PyObject *o, char *attr_name, PyObject *v); + + Set the value of the attribute named attr_name, for object o, + to the value, v. Returns -1 on failure. This is + the equivalent of the Python statement: o.attr_name=v. + + */ + + /* Implemented elsewhere: + + int PyObject_SetAttr(PyObject *o, PyObject *attr_name, PyObject *v); + + Set the value of the attribute named attr_name, for object o, + to the value, v. Returns -1 on failure. This is + the equivalent of the Python statement: o.attr_name=v. + + */ + + /* implemented as a macro: + + int PyObject_DelAttrString(PyObject *o, char *attr_name); + + Delete attribute named attr_name, for object o. Returns + -1 on failure. This is the equivalent of the Python + statement: del o.attr_name. + + */ +#define PyObject_DelAttrString(O,A) PyObject_SetAttrString((O),(A),NULL) + + /* implemented as a macro: + + int PyObject_DelAttr(PyObject *o, PyObject *attr_name); + + Delete attribute named attr_name, for object o. Returns -1 + on failure. This is the equivalent of the Python + statement: del o.attr_name. + + */ +#define PyObject_DelAttr(O,A) PyObject_SetAttr((O),(A),NULL) + + int PyObject_Cmp(PyObject *o1, PyObject *o2, int *result); + + /* + Compare the values of o1 and o2 using a routine provided by + o1, if one exists, otherwise with a routine provided by o2. + The result of the comparison is returned in result. Returns + -1 on failure. This is the equivalent of the Python + statement: result=cmp(o1,o2). + + */ + + /* Implemented elsewhere: + + int PyObject_Compare(PyObject *o1, PyObject *o2); + + Compare the values of o1 and o2 using a routine provided by + o1, if one exists, otherwise with a routine provided by o2. + Returns the result of the comparison on success. On error, + the value returned is undefined. This is equivalent to the + Python expression: cmp(o1,o2). + + */ + + /* Implemented elsewhere: + + PyObject *PyObject_Repr(PyObject *o); + + Compute the string representation of object, o. Returns the + string representation on success, NULL on failure. This is + the equivalent of the Python expression: repr(o). + + Called by the repr() built-in function and by reverse quotes. + + */ + + /* Implemented elsewhere: + + PyObject *PyObject_Str(PyObject *o); + + Compute the string representation of object, o. Returns the + string representation on success, NULL on failure. This is + the equivalent of the Python expression: str(o).) + + Called by the str() built-in function and by the print + statement. + + */ + + int PyCallable_Check(PyObject *o); + + /* + Determine if the object, o, is callable. Return 1 if the + object is callable and 0 otherwise. + + This function always succeeds. + + */ + + + + PyObject *PyObject_CallObject(PyObject *callable_object, PyObject *args); + + /* + + Call a callable Python object, callable_object, with + arguments given by the tuple, args. If no arguments are + needed, then args may be NULL. Returns the result of the + call on success, or NULL on failure. This is the equivalent + of the Python expression: apply(o,args). + + */ + + PyObject *PyObject_CallFunction(PyObject *callable_object, char *format, ...); + + /* + Call a callable Python object, callable_object, with a + variable number of C arguments. The C arguments are described + using a mkvalue-style format string. The format may be NULL, + indicating that no arguments are provided. Returns the + result of the call on success, or NULL on failure. This is + the equivalent of the Python expression: apply(o,args). + + */ + + + PyObject *PyObject_CallMethod(PyObject *o, char *m, char *format, ...); + + /* + Call the method named m of object o with a variable number of + C arguments. The C arguments are described by a mkvalue + format string. The format may be NULL, indicating that no + arguments are provided. Returns the result of the call on + success, or NULL on failure. This is the equivalent of the + Python expression: o.method(args). + + Note that Special method names, such as "__add__", + "__getitem__", and so on are not supported. The specific + abstract-object routines for these must be used. + + */ + + + /* Implemented elsewhere: + + long PyObject_Hash(PyObject *o); + + Compute and return the hash, hash_value, of an object, o. On + failure, return -1. This is the equivalent of the Python + expression: hash(o). + + */ + + + /* Implemented elsewhere: + + int PyObject_IsTrue(PyObject *o); + + Returns 1 if the object, o, is considered to be true, and + 0 otherwise. This is equivalent to the Python expression: + not not o + + This function always succeeds. + + */ + + PyObject *PyObject_Type(PyObject *o); + + /* + On success, returns a type object corresponding to the object + type of object o. On failure, returns NULL. This is + equivalent to the Python expression: type(o). + */ + + int PyObject_Length(PyObject *o); + + /* + Return the length of object o. If the object, o, provides + both sequence and mapping protocols, the sequence length is + returned. On error, -1 is returned. This is the equivalent + to the Python expression: len(o). + + */ + + PyObject *PyObject_GetItem(PyObject *o, PyObject *key); + + /* + Return element of o corresponding to the object, key, or NULL + on failure. This is the equivalent of the Python expression: + o[key]. + + */ + + int PyObject_SetItem(PyObject *o, PyObject *key, PyObject *v); + + /* + Map the object, key, to the value, v. Returns + -1 on failure. This is the equivalent of the Python + statement: o[key]=v. + */ + + +/* Number Protocol:*/ + + int PyNumber_Check(PyObject *o); + + /* + Returns 1 if the object, o, provides numeric protocols, and + false otherwise. + + This function always succeeds. + + */ + + PyObject *PyNumber_Add(PyObject *o1, PyObject *o2); + + /* + Returns the result of adding o1 and o2, or null on failure. + This is the equivalent of the Python expression: o1+o2. + + + */ + + PyObject *PyNumber_Subtract(PyObject *o1, PyObject *o2); + + /* + Returns the result of subtracting o2 from o1, or null on + failure. This is the equivalent of the Python expression: + o1-o2. + + */ + + PyObject *PyNumber_Multiply(PyObject *o1, PyObject *o2); + + /* + Returns the result of multiplying o1 and o2, or null on + failure. This is the equivalent of the Python expression: + o1*o2. + + + */ + + PyObject *PyNumber_Divide(PyObject *o1, PyObject *o2); + + /* + Returns the result of dividing o1 by o2, or null on failure. + This is the equivalent of the Python expression: o1/o2. + + + */ + + PyObject *PyNumber_Remainder(PyObject *o1, PyObject *o2); + + /* + Returns the remainder of dividing o1 by o2, or null on + failure. This is the equivalent of the Python expression: + o1%o2. + + + */ + + PyObject *PyNumber_Divmod(PyObject *o1, PyObject *o2); + + /* + See the built-in function divmod. Returns NULL on failure. + This is the equivalent of the Python expression: + divmod(o1,o2). + + + */ + + PyObject *PyNumber_Power(PyObject *o1, PyObject *o2, PyObject *o3); + + /* + See the built-in function pow. Returns NULL on failure. + This is the equivalent of the Python expression: + pow(o1,o2,o3), where o3 is optional. + + */ + + PyObject *PyNumber_Negative(PyObject *o); + + /* + Returns the negation of o on success, or null on failure. + This is the equivalent of the Python expression: -o. + + */ + + PyObject *PyNumber_Positive(PyObject *o); + + /* + Returns the (what?) of o on success, or NULL on failure. + This is the equivalent of the Python expression: +o. + + */ + + PyObject *PyNumber_Absolute(PyObject *o); + + /* + Returns the absolute value of o, or null on failure. This is + the equivalent of the Python expression: abs(o). + + */ + + PyObject *PyNumber_Invert(PyObject *o); + + /* + Returns the bitwise negation of o on success, or NULL on + failure. This is the equivalent of the Python expression: + ~o. + + + */ + + PyObject *PyNumber_Lshift(PyObject *o1, PyObject *o2); + + /* + Returns the result of left shifting o1 by o2 on success, or + NULL on failure. This is the equivalent of the Python + expression: o1 << o2. + + + */ + + PyObject *PyNumber_Rshift(PyObject *o1, PyObject *o2); + + /* + Returns the result of right shifting o1 by o2 on success, or + NULL on failure. This is the equivalent of the Python + expression: o1 >> o2. + + */ + + PyObject *PyNumber_And(PyObject *o1, PyObject *o2); + + /* + Returns the result of "anding" o2 and o2 on success and NULL + on failure. This is the equivalent of the Python + expression: o1 and o2. + + + */ + + PyObject *PyNumber_Xor(PyObject *o1, PyObject *o2); + + /* + Returns the bitwise exclusive or of o1 by o2 on success, or + NULL on failure. This is the equivalent of the Python + expression: o1^o2. + + + */ + + PyObject *PyNumber_Or(PyObject *o1, PyObject *o2); + + /* + Returns the result or o1 and o2 on success, or NULL on + failure. This is the equivalent of the Python expression: + o1 or o2. + + */ + + /* Implemented elsewhere: + + int PyNumber_Coerce(PyObject *o1, PyObject *o2); + + On success, returns a tuple containing o1 and o2 converted to + a common numeric type, or None if no conversion is possible. + Returns -1 on failure. This is equivalent to the Python + expression: coerce(o1,o2). + + */ + + PyObject *PyNumber_Int(PyObject *o); + + /* + Returns the o converted to an integer object on success, or + NULL on failure. This is the equivalent of the Python + expression: int(o). + + */ + + PyObject *PyNumber_Long(PyObject *o); + + /* + Returns the o converted to a long integer object on success, + or NULL on failure. This is the equivalent of the Python + expression: long(o). + + */ + + PyObject *PyNumber_Float(PyObject *o); + + /* + Returns the o converted to a float object on success, or NULL + on failure. This is the equivalent of the Python expression: + float(o). + */ + + +/* Sequence protocol:*/ + + int PySequence_Check(PyObject *o); + + /* + Return 1 if the object provides sequence protocol, and zero + otherwise. + + This function always succeeds. + + */ + + PyObject *PySequence_Concat(PyObject *o1, PyObject *o2); + + /* + Return the concatination of o1 and o2 on success, and NULL on + failure. This is the equivalent of the Python + expression: o1+o2. + + */ + + PyObject *PySequence_Repeat(PyObject *o, int count); + + /* + Return the result of repeating sequence object o count times, + or NULL on failure. This is the equivalent of the Python + expression: o1*count. + + */ + + PyObject *PySequence_GetItem(PyObject *o, int i); + + /* + Return the ith element of o, or NULL on failure. This is the + equivalent of the Python expression: o[i]. + + */ + + PyObject *PySequence_GetSlice(PyObject *o, int i1, int i2); + + /* + Return the slice of sequence object o between i1 and i2, or + NULL on failure. This is the equivalent of the Python + expression: o[i1:i2]. + + */ + + int PySequence_SetItem(PyObject *o, int i, PyObject *v); + + /* + Assign object v to the ith element of o. Returns + -1 on failure. This is the equivalent of the Python + statement: o[i]=v. + + */ + + int PySequence_SetSlice(PyObject *o, int i1, int i2, PyObject *v); + + /* + Assign the sequence object, v, to the slice in sequence + object, o, from i1 to i2. Returns -1 on failure. This is the + equivalent of the Python statement: o[i1:i2]=v. + */ + + PyObject *PySequence_Tuple(PyObject *o); + + /* + Returns the o as a tuple on success, and NULL on failure. + This is equivalent to the Python expression: tuple(o) + */ + + int PySequence_Count(PyObject *o, PyObject *value); + + /* + Return the number of occurrences on value on o, that is, + return the number of keys for which o[key]==value. On + failure, return -1. This is equivalent to the Python + expression: o.count(value). + */ + + int PySequence_In(PyObject *o, PyObject *value); + + /* + Determine if o contains value. If an item in o is equal to + X, return 1, otherwise return 0. On error, return -1. This + is equivalent to the Python expression: value in o. + */ + + int PySequence_Index(PyObject *o, PyObject *value); + + /* + Return the first index for which o[i]=value. On error, + return -1. This is equivalent to the Python + expression: o.index(value). + */ + +/* Mapping protocol:*/ + + int PyMapping_Check(PyObject *o); + + /* + Return 1 if the object provides mapping protocol, and zero + otherwise. + + This function always succeeds. + */ + + int PyMapping_Length(PyObject *o); + + /* + Returns the number of keys in object o on success, and -1 on + failure. For objects that do not provide sequence protocol, + this is equivalent to the Python expression: len(o). + */ + + int PyMapping_DelItemString(PyObject *o, char *key); + + /* + Remove the mapping for object, key, from the object *o. + Returns -1 on failure. This is equivalent to + the Python statement: del o[key]. + */ + + int PyMapping_DelItem(PyObject *o, PyObject *key); + + /* + Remove the mapping for object, key, from the object *o. + Returns -1 on failure. This is equivalent to + the Python statement: del o[key]. + */ + + int PyMapping_HasKeyString(PyObject *o, char *key); + + /* + On success, return 1 if the mapping object has the key, key, + and 0 otherwise. This is equivalent to the Python expression: + o.has_key(key). + + This function always succeeds. + */ + + int PyMapping_HasKey(PyObject *o, PyObject *key); + + /* + Return 1 if the mapping object has the key, key, + and 0 otherwise. This is equivalent to the Python expression: + o.has_key(key). + + This function always succeeds. + + */ + + /* Implemented as macro: + + PyObject *PyMapping_Keys(PyObject *o); + + On success, return a list of the keys in object o. On + failure, return NULL. This is equivalent to the Python + expression: o.keys(). + */ +#define PyMapping_Keys(O) PyObject_CallMethod(O,"keys",NULL) + + /* Implemented as macro: + + PyObject *PyMapping_Values(PyObject *o); + + On success, return a list of the values in object o. On + failure, return NULL. This is equivalent to the Python + expression: o.values(). + */ +#define PyMapping_Values(O) PyObject_CallMethod(O,"values",NULL) + + /* Implemented as macro: + + PyObject *PyMapping_Items(PyObject *o); + + On success, return a list of the items in object o, where + each item is a tuple containing a key-value pair. On + failure, return NULL. This is equivalent to the Python + expression: o.items(). + + */ +#define PyMapping_Items(O) PyObject_CallMethod(O,"items",NULL) + + PyObject *PyMapping_GetItemString(PyObject *o, char *key); + + /* + Return element of o corresponding to the object, key, or NULL + on failure. This is the equivalent of the Python expression: + o[key]. + */ + + int PyMapping_SetItemString(PyObject *o, char *key, PyObject *value); + + /* + Map the object, key, to the value, v. Returns + -1 on failure. This is the equivalent of the Python + statement: o[key]=v. + */ + + +#endif /* Py_ABSTRACTOBJECT_H */ |