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C API for Handwritten Code

In this section we describe the API that can be used by handwritten code in specification files.

SIP_API_MAJOR_NR
This is a C preprocessor symbol that defines the major number of the SIP API. Its value is a number. There is no direct relationship between this and the SIP version number.
SIP_API_MINOR_NR
This is a C preprocessor symbol that defines the minor number of the SIP API. Its value is a number. There is no direct relationship between this and the SIP version number.
SIP_BLOCK_THREADS
This is a C preprocessor macro that will make sure the Python Global Interpreter Lock (GIL) is acquired. Python API calls must only be made when the GIL has been acquired. There must be a corresponding SIP_UNBLOCK_THREADS at the same lexical scope.
SIP_NO_CONVERTORS
This is a flag used by various type convertors that suppresses the use of a type’s %ConvertToTypeCode.
SIP_NOT_NONE
This is a flag used by various type convertors that causes the conversion to fail if the Python object being converted is Py_None.
SIP_PROTECTED_IS_PUBLIC

New in version 4.10.

This is a C preprocessor macro that is set automatically by the build system to specify that the generated code is being compiled with protected redefined as public. This allows handwritten code to determine if the generated helper functions for accessing protected C++ functions are available (see %MethodCode).

SIP_SSIZE_T
This is a C preprocessor macro that is defined as Py_ssize_t for Python v2.5 and later, and as int for earlier versions of Python. It makes it easier to write PEP 353 compliant handwritten code.
SIP_UNBLOCK_THREADS
This is a C preprocessor macro that will restore the Python Global Interpreter Lock (GIL) to the state it was prior to the corresponding SIP_BLOCK_THREADS.
SIP_VERSION
This is a C preprocessor symbol that defines the SIP version number represented as a 3 part hexadecimal number (e.g. v4.0.0 is represented as 0x040000).
SIP_VERSION_STR
This is a C preprocessor symbol that defines the SIP version number represented as a string. For development snapshots it will start with snapshot-.
sipErrorState sipBadCallableArg(int arg_nr, PyObject *arg)

New in version 4.10.

This is called from %MethodCode to raise a Python exception when an argument to a function, a C++ constructor or method is found to have an unexpected type. This should be used when the %MethodCode does additional type checking of the supplied arguments.

Parameters:
  • arg_nr – the number of the argument. Arguments are numbered from 0 but are numbered from 1 in the detail of the exception.
  • arg – the argument.
Returns:

the value that should be assigned to sipError.
void sipBadCatcherResult(PyObject *method)

This raises a Python exception when the result of a Python reimplementation of a C++ method doesn’t have the expected type. It is normally called by handwritten code specified with the %VirtualCatcherCode directive.

Parameter:method – the Python method and would normally be the supplied sipMethod.
void sipBadLengthForSlice(SIP_SSIZE_T seqlen, SIP_SSIZE_T slicelen)

This raises a Python exception when the length of a slice object is inappropriate for a sequence-like object. It is normally called by handwritten code specified for __setitem__() methods.

Parameters:
  • seqlen – the length of the sequence.
  • slicelen – the length of the slice.
PyObject *sipBuildResult(int *iserr, const char *format, ...)

This creates a Python object based on a format string and associated values in a similar way to the Python Py_BuildValue() function.

Parameters:
  • iserr – if this is not NULL then the location it points to is set to a non-zero value.
  • format – the string of format characters.
Returns:

If there was an error then NULL is returned and a Python exception is raised.

If the format string begins and ends with parentheses then a tuple of objects is created. If it contains more than one format character then parentheses must be specified.

In the following description the first letter is the format character, the entry in parentheses is the Python object type that the format character will create, and the entry in brackets are the types of the C/C++ values to be passed.

a (string) [char]
Convert a C/C++ char to a Python v2 or v3 string object.
b (boolean) [int]
Convert a C/C++ int to a Python boolean.
c (string/bytes) [char]
Convert a C/C++ char to a Python v2 string object or a Python v3 bytes object.
d (float) [double]
Convert a C/C++ double to a Python floating point number.
e (integer) [enum]
Convert an anonymous C/C++ enum to a Python integer.
f (float) [float]
Convert a C/C++ float to a Python floating point number.
g (string/bytes) [char *, SIP_SSIZE_T]
Convert a C/C++ character array and its length to a Python v2 string object or a Python v3 bytes object. If the array is NULL then the length is ignored and the result is Py_None.
h (integer) [short]
Convert a C/C++ short to a Python integer.
i (integer) [int]
Convert a C/C++ int to a Python integer.
l (long) [long]
Convert a C/C++ long to a Python integer.
m (long) [unsigned long]
Convert a C/C++ unsigned long to a Python long.
n (long) [long long]
Convert a C/C++ long long to a Python long.
o (long) [unsigned long long]
Convert a C/C++ unsigned long long to a Python long.
r (wrapped instance) [type *, SIP_SSIZE_T, const sipTypeDef *]
Convert an array of C structures, C++ classes or mapped type instances to a Python tuple. Note that copies of the array elements are made.
s (string/bytes) [char *]
Convert a C/C++ '\0' terminated string to a Python v2 string object or a Python v3 bytes object. If the string pointer is NULL then the result is Py_None.
t (long) [unsigned short]
Convert a C/C++ unsigned short to a Python long.
u (long) [unsigned int]
Convert a C/C++ unsigned int to a Python long.
w (tqunicode/string) [wchar_t]
Convert a C/C++ wide character to a Python v2 tqunicode object or a Python v3 string object.
x (tqunicode/string) [wchar_t *]
Convert a C/C++ L'\0' terminated wide character string to a Python v2 tqunicode object or a Python v3 string object. If the string pointer is NULL then the result is Py_None.
A (string) [char *]
Convert a C/C++ '\0' terminated string to a Python v2 or v3 string object. If the string pointer is NULL then the result is Py_None.
B (wrapped instance) [type *, sipWrapperType *, PyObject *]

Convert a new C structure or a new C++ class instance to a Python class instance object. Ownership of the structure or instance is determined by the PyObject * argument. If it is NULL and the instance has already been wrapped then the ownership is unchanged. If it is NULL or Py_None then ownership will be with Python. Otherwise ownership will be with C/C++ and the instance associated with the PyObject * argument. The Python class is influenced by any applicable %ConvertToSubClassCode code.

Note

This is deprecated from SIP v4.8. Instead you should use N.

C (wrapped instance) [type *, sipWrapperType *, PyObject *]

Convert a C structure or a C++ class instance to a Python class instance object. If the structure or class instance has already been wrapped then the result is a new reference to the existing class instance object. Ownership of the structure or instance is determined by the PyObject * argument. If it is NULL and the instance has already been wrapped then the ownership is unchanged. If it is NULL and the instance is newly wrapped then ownership will be with C/C++. If it is Py_None then ownership is transferred to Python via a call to sipTransferBack(). Otherwise ownership is transferred to C/C++ and the instance associated with the PyObject * argument via a call to sipTransferTo(). The Python class is influenced by any applicable %ConvertToSubClassCode code.

Note

This is deprecated from SIP v4.8. Instead you should use D.

D (wrapped instance) [type *, const sipTypeDef *, PyObject *]
Convert a C structure, C++ class or mapped type instance to a Python object. If the instance has already been wrapped then the result is a new reference to the existing object. Ownership of the instance is determined by the PyObject * argument. If it is NULL and the instance has already been wrapped then the ownership is unchanged. If it is NULL and the instance is newly wrapped then ownership will be with C/C++. If it is Py_None then ownership is transferred to Python via a call to sipTransferBack(). Otherwise ownership is transferred to C/C++ and the instance associated with the PyObject * argument via a call to sipTransferTo(). The Python class is influenced by any applicable %ConvertToSubClassCode code.
E (wrapped enum) [enum, PyTypeObject *]

Convert a named C/C++ enum to an instance of the corresponding Python named enum type.

Note

This is deprecated from SIP v4.8. Instead you should use F.

F (wrapped enum) [enum, sipTypeDef *]
Convert a named C/C++ enum to an instance of the corresponding Python named enum type.
G (tqunicode) [wchar_t *, SIP_SSIZE_T]
Convert a C/C++ wide character array and its length to a Python tqunicode object. If the array is NULL then the length is ignored and the result is Py_None.
N (wrapped instance) [type *, sipTypeDef *, PyObject *]
Convert a new C structure, C++ class or mapped type instance to a Python object. Ownership of the instance is determined by the PyObject * argument. If it is NULL and the instance has already been wrapped then the ownership is unchanged. If it is NULL or Py_None then ownership will be with Python. Otherwise ownership will be with C/C++ and the instance associated with the PyObject * argument. The Python class is influenced by any applicable %ConvertToSubClassCode code.
R (object) [PyObject *]
The result is value passed without any conversions. The reference count is unaffected, i.e. a reference is taken.
S (object) [PyObject *]
The result is value passed without any conversions. The reference count is incremented.
V (sip.voidptr) [void *]
Convert a C/C++ void * Python sip.voidptr object.
PyObject *sipCallMethod(int *iserr, PyObject *method, const char *format, ...)

This calls a Python method passing a tuple of arguments based on a format string and associated values in a similar way to the Python PyObject_CallObject() function.

Parameters:
  • iserr – if this is not NULL then the location it points to is set to a non-zero value if there was an error.
  • method – the Python bound method to call.
  • format – the string of format characters (see sipBuildResult()).
Returns:

If there was an error then NULL is returned and a Python exception is raised.

It is normally called by handwritten code specified with the %VirtualCatcherCode directive with method being the supplied sipMethod.

int sipCanConvertToEnum(PyObject *obj, const sipTypeDef *td)

This checks if a Python object can be converted to a named enum.

Parameters:
Returns:

a non-zero value if the object can be converted.
int sipCanConvertToInstance(PyObject *obj, sipWrapperType *type, int flags)

This checks if a Python object can be converted to an instance of a C structure or C++ class.

Parameters:
Returns:

a non-zero value if the object can be converted.

Note

This is deprecated from SIP v4.8. Instead you should use sipCanConvertToType().

int sipCanConvertToMappedType(PyObject *obj, const sipMappedType *mt, int flags)

This checks if a Python object can be converted to an instance of a C structure or C++ class which has been implemented as a mapped type.

Parameters:
Returns:

a non-zero value if the object can be converted.

Note

This is deprecated from SIP v4.8. Instead you should use sipCanConvertToType().

int sipCanConvertToType(PyObject *obj, const sipTypeDef *td, int flags)

This checks if a Python object can be converted to an instance of a C structure, C++ class or mapped type.

Parameters:
Returns:

a non-zero value if the object can be converted.
PyObject *sipClassName(PyObject *obj)

This gets the class name of a wrapped instance as a Python string. It comes with a reference.

Parameter:obj – the wrapped instance.
Returns:the name of the instance’s class.

Note

This is deprecated from SIP v4.8. Instead you should use the following:

PyString_FromString(obj->ob_type->tp_name)
PyObject *sipConvertFromConstVoidPtr(const void *cpp)

This creates a sip.voidptr object for a memory address. The object will not be writeable and has no associated size.

Parameter:cpp – the memory address.
Returns:the sip.voidptr object.
PyObject *sipConvertFromConstVoidPtrAndSize(const void *cpp, SIP_SSIZE_T size)

This creates a sip.voidptr object for a memory address. The object will not be writeable and can be used as an immutable buffer object.

Parameters:
  • cpp – the memory address.
  • size – the size associated with the address.
Returns:

the sip.voidptr object.
PyObject *sipConvertFromEnum(int eval, const sipTypeDef *td)

This converts a named C/C++ enum to an instance of the corresponding generated Python type.

Parameters:
Returns:

the Python object.
PyObject *sipConvertFromInstance(void *cpp, sipWrapperType *type, PyObject *transferObj)

This converts a C structure or a C++ class instance to an instance of the corresponding generated Python type.

Parameters:
  • cpp – the C/C++ instance.
  • type – the type’s generated type object.
  • transferObj – this controls the ownership of the returned value.
Returns:

the Python object.

If the C/C++ instance has already been wrapped then the result is a new reference to the existing class instance object.

If transferObj is NULL and the instance has already been wrapped then the ownership is unchanged.

If transferObj is NULL and the instance is newly wrapped then ownership will be with C/C++.

If transferObj is Py_None then ownership is transferred to Python via a call to sipTransferBack().

Otherwise ownership is transferred to C/C++ and the instance associated with transferObj via a call to sipTransferTo().

The Python type is influenced by any applicable %ConvertToSubClassCode code.

Note

This is deprecated from SIP v4.8. Instead you should use sipConvertFromType().

PyObject *sipConvertFromMappedType(void *cpp, const sipMappedType *mt, PyObject *transferObj)

This converts a C structure or a C++ class instance wrapped as a mapped type to an instance of the corresponding generated Python type.

Parameters:
  • cpp – the C/C++ instance.
  • mt – the opaque structure returned by sipFindMappedType().
  • transferObj – this controls the ownership of the returned value.
Returns:

the Python object.

If transferObj is NULL then the ownership is unchanged.

If transferObj is Py_None then ownership is transferred to Python via a call to sipTransferBack().

Otherwise ownership is transferred to C/C++ and the instance associated with transferObj argument via a call to sipTransferTo().

Note

This is deprecated from SIP v4.8. Instead you should use sipConvertFromType().

PyObject *sipConvertFromNamedEnum(int eval, PyTypeObject *type)

This converts a named C/C++ enum to an instance of the corresponding generated Python type.

Parameters:
Returns:

the Python object.

Note

This is deprecated from SIP v4.8. Instead you should use sipConvertFromEnum().

PyObject *sipConvertFromNewInstance(void *cpp, sipWrapperType *type, PyObject *transferObj)

This converts a new C structure or a C++ class instance to an instance of the corresponding generated Python type.

Parameters:
  • cpp – the C/C++ instance.
  • type – the type’s generated type object.
  • transferObj – this controls the ownership of the returned value.
Returns:

the Python object.

If transferObj is NULL or Py_None then ownership will be with Python.

Otherwise ownership will be with C/C++ and the instance associated with transferObj.

The Python type is influenced by any applicable %ConvertToSubClassCode code.

Note

This is deprecated from SIP v4.8. Instead you should use sipConvertFromNewType().

PyObject *sipConvertFromNewType(void *cpp, const sipTypeDef *td, PyObject *transferObj)

This converts a new C structure or a C++ class instance to an instance of the corresponding generated Python type.

Parameters:
  • cpp – the C/C++ instance.
  • td – the type’s generated type structure.
  • transferObj – this controls the ownership of the returned value.
Returns:

the Python object.

If transferObj is NULL or Py_None then ownership will be with Python.

Otherwise ownership will be with C/C++ and the instance associated with transferObj.

The Python type is influenced by any applicable %ConvertToSubClassCode code.

SIP_SSIZE_T sipConvertFromSequenceIndex(SIP_SSIZE_T idx, SIP_SSIZE_T len)

This converts a Python sequence index (i.e. where a negative value refers to the offset from the end of the sequence) to a C/C++ array index. If the index was out of range then a negative value is returned and a Python exception raised.

Parameters:
  • idx – the sequence index.
  • len – the length of the sequence.
Returns:

the unsigned array index.
int sipConvertFromSliceObject(PyObject *slice, SIP_SSIZE_T length, SIP_SSIZE_T *start, SIP_SSIZE_T *stop, SIP_SSIZE_T *step, SIP_SSIZE_T *slicelength)
This is a thin wrapper around the Python PySlice_GetIndicesEx() function provided to make it easier to write handwritten code that is compatible with SIP v3.x and versions of Python earlier that v2.3.
PyObject *sipConvertFromType(void *cpp, const sipTypeDef *td, PyObject *transferObj)

This converts a C structure or a C++ class instance to an instance of the corresponding generated Python type.

Parameters:
  • cpp – the C/C++ instance.
  • td – the type’s generated type structure.
  • transferObj – this controls the ownership of the returned value.
Returns:

the Python object.

If the C/C++ instance has already been wrapped then the result is a new reference to the existing object.

If transferObj is NULL and the instance has already been wrapped then the ownership is unchanged.

If transferObj is NULL and the instance is newly wrapped then ownership will be with C/C++.

If transferObj is Py_None then ownership is transferred to Python via a call to sipTransferBack().

Otherwise ownership is transferred to C/C++ and the instance associated with transferObj via a call to sipTransferTo().

The Python class is influenced by any applicable %ConvertToSubClassCode code.

PyObject *sipConvertFromVoidPtr(void *cpp)

This creates a sip.voidptr object for a memory address. The object will be writeable but has no associated size.

Parameter:cpp – the memory address.
Returns:the sip.voidptr object.
PyObject *sipConvertFromVoidPtrAndSize(void *cpp, SIP_SSIZE_T size)

This creates a sip.voidptr object for a memory address. The object will be writeable and can be used as a mutable buffer object.

Parameters:
  • cpp – the memory address.
  • size – the size associated with the address.
Returns:

the sip.voidptr object.
void *sipConvertToInstance(PyObject *obj, sipWrapperType *type, PyObject *transferObj, int flags, int *state, int *iserr)

This converts a Python object to an instance of a C structure or C++ class assuming that a previous call to sipCanConvertToInstance() has been successful.

Parameters:
  • obj – the Python object.
  • type – the type’s generated type object.
  • transferObj – this controls any ownership changes to obj.
  • flags – any combination of the SIP_NOT_NONE and SIP_NO_CONVERTORS flags.
  • state – the state of the returned C/C++ instance is returned via this pointer.
  • iserr – the error flag is passed and updated via this pointer.
Returns:

the C/C++ instance.

If transferObj is NULL then the ownership is unchanged.

If transferObj is Py_None then ownership is transferred to Python via a call to sipTransferBack().

Otherwise ownership is transferred to C/C++ and obj associated with transferObj via a call to sipTransferTo().

If state is not NULL then the location it points to is set to describe the state of the returned C/C++ instance and is the value returned by any %ConvertToTypeCode. The calling code must then release the value at some point to prevent a memory leak by calling sipReleaseInstance().

If there is an error then the location iserr points to is set to a non-zero value. If it was initially a non-zero value then the conversion isn’t attempted in the first place. (This allows several calls to be made that share the same error flag so that it only needs to be tested once rather than after each call.)

Note

This is deprecated from SIP v4.8. Instead you should use sipConvertToType().

void *sipConvertToMappedType(PyObject *obj, const sipMappedType *mt, PyObject *transferObj, int flags, int *state, int *iserr)

This converts a Python object to an instance of a C structure or C++ class that is implemented as a mapped type assuming that a previous call to sipCanConvertToMappedType() has been successful.

Parameters:
  • obj – the Python object.
  • mt – the opaque structure returned by sipFindMappedType().
  • transferObj – this controls any ownership changes to obj.
  • flags – this may be the SIP_NOT_NONE flag.
  • state – the state of the returned C/C++ instance is returned via this pointer.
  • iserr – the error flag is passed and updated via this pointer.
Returns:

the C/C++ instance.

If transferObj is NULL then the ownership is unchanged.

If transferObj is Py_None then ownership is transferred to Python via a call to sipTransferBack().

Otherwise ownership is transferred to C/C++ and obj associated with transferObj via a call to sipTransferTo().

If state is not NULL then the location it points to is set to describe the state of the returned C/C++ instance and is the value returned by any %ConvertToTypeCode. The calling code must then release the value at some point to prevent a memory leak by calling sipReleaseMappedType().

If there is an error then the location iserr points to is set to a non-zero value. If it was initially a non-zero value then the conversion isn’t attempted in the first place. (This allows several calls to be made that share the same error flag so that it only needs to be tested once rather than after each call.)

Note

This is deprecated from SIP v4.8. Instead you should use sipConvertToType()

void *sipConvertToType(PyObject *obj, const sipTypeDef *td, PyObject *transferObj, int flags, int *state, int *iserr)

This converts a Python object to an instance of a C structure, C++ class or mapped type assuming that a previous call to sipCanConvertToType() has been successful.

Parameters:
  • obj – the Python object.
  • td – the type’s generated type structure.
  • transferObj – this controls any ownership changes to obj.
  • flags – any combination of the SIP_NOT_NONE and SIP_NO_CONVERTORS flags.
  • state – the state of the returned C/C++ instance is returned via this pointer.
  • iserr – the error flag is passed and updated via this pointer.
Returns:

the C/C++ instance.

If transferObj is NULL then the ownership is unchanged. If it is Py_None then ownership is transferred to Python via a call to sipTransferBack().

Otherwise ownership is transferred to C/C++ and obj associated with transferObj via a call to sipTransferTo().

If state is not NULL then the location it points to is set to describe the state of the returned C/C++ instance and is the value returned by any %ConvertToTypeCode. The calling code must then release the value at some point to prevent a memory leak by calling sipReleaseType().

If there is an error then the location iserr points to is set to a non-zero value. If it was initially a non-zero value then the conversion isn’t attempted in the first place. (This allows several calls to be made that share the same error flag so that it only needs to be tested once rather than after each call.)

void *sipConvertToVoidPtr(PyObject *obj)

This converts a Python object to a memory address. PyErr_Occurred() must be used to determine if the conversion was successful.

Parameter:obj – the Python object which may be Py_None, a sip.voidptr or a PyCObject.
Returns:the memory address.
int sipExportSymbol(const char *name, void *sym)

Python does not allow extension modules to directly access symbols in another extension module. This exports a symbol, referenced by a name, that can subsequently be imported, using sipImportSymbol(), by another module.

Parameters:
  • name – the name of the symbol.
  • sym – the value of the symbol.
Returns:

0 if there was no error. A negative value is returned if name is already associated with a symbol or there was some other error.
sipWrapperType *sipFindClass(const char *type)

This returns a pointer to the generated type object corresponding to a C/C++ type.

Parameter:type – the C/C++ declaration of the type.
Returns:the generated type object. This will not change and may be saved in a static cache. NULL is returned if the C/C++ type doesn’t exist.

Note

This is deprecated from SIP v4.8. Instead you should use sipFindType().

const sipMappedType *sipFindMappedType(const char *type)

This returns a pointer to an opaque structure describing a mapped type.

Parameter:type – the C/C++ declaration of the type.
Returns:the opaque structure. This will not change and may be saved in a static cache. NULL is returned if the C/C++ type doesn’t exist.

Note

This is deprecated from SIP v4.8. Instead you should use sipFindType().

PyTypeObject *sipFindNamedEnum(const char *type)

This returns a pointer to the generated Python type object corresponding to a named C/C++ enum.

Parameter:type – the C/C++ declaration of the enum.
Returns:the generated Python type object. This will not change and may be saved in a static cache. NULL is returned if the C/C++ enum doesn’t exist.

Note

This is deprecated from SIP v4.8. Instead you should use sipFindType().

const sipTypeDef *sipFindType(const char *type)

This returns a pointer to the generated type structure corresponding to a C/C++ type.

Parameter:type – the C/C++ declaration of the type.
Returns:the generated type structure. This will not change and may be saved in a static cache. NULL is returned if the C/C++ type doesn’t exist.
void *sipForceConvertToInstance(PyObject *obj, sipWrapperType *type, PyObject *transferObj, int flags, int *state, int *iserr)

This converts a Python object to an instance of a C structure or C++ class by calling sipCanConvertToInstance() and, if it is successfull, calling sipConvertToInstance().

See sipConvertToInstance() for a full description of the arguments.

Note

This is deprecated from SIP v4.8. Instead you should use sipForceConvertToType().

void *sipForceConvertToMappedType(PyObject *obj, const sipMappedType *mt, PyObject *transferObj, int flags, int *state, int *iserr)

This converts a Python object to an instance of a C structure or C++ class which has been implemented as a mapped type by calling sipCanConvertToMappedType() and, if it is successfull, calling sipConvertToMappedType().

See sipConvertToMappedType() for a full description of the arguments.

Note

This is deprecated from SIP v4.8. Instead you should use sipForceConvertToType().

void *sipForceConvertToType(PyObject *obj, const sipTypeDef *td, PyObject *transferObj, int flags, int *state, int *iserr)

This converts a Python object to an instance of a C structure, C++ class or mapped type by calling sipCanConvertToType() and, if it is successfull, calling sipConvertToType().

See sipConvertToType() for a full description of the arguments.

void sipFree(void *mem)

This returns an area of memory allocated by sipMalloc() to the heap.

Parameter:mem – the memory address.
PyObject *sipGetPyObject(void *cppptr, const sipTypeDef *td)

This returns a borrowed reference to the Python object for a C structure or C++ class instance.

Parameters:
Returns:

the Python object or NULL (and no exception is raised) if the C/C++ instance hasn’t been wrapped.
int sipGetState(PyObject *transferObj)

The %ConvertToTypeCode directive requires that the provided code returns an int describing the state of the converted value. The state usually depends on any transfers of ownership that have been requested. This is a convenience function that returns the correct state when the converted value is a temporary.

Parameter:transferObj – the object that describes the requested transfer of ownership.
Returns:the state of the converted value.
PyObject *sipGetWrapper(void *cppptr, sipWrapperType *type)

This returns a borrowed reference to the wrapped instance object for a C structure or C++ class instance.

Parameters:
  • cppptr – the pointer to the C/C++ instance.
  • type – the generated type object corresponding to the C/C++ type.
Returns:

the Python object or NULL (and no exception is raised) if the C/C++ instance hasn’t been wrapped.

Note

This is deprecated from SIP v4.8. Instead you should use sipGetPyObject().

void *sipImportSymbol(const char *name)

Python does not allow extension modules to directly access symbols in another extension module. This imports a symbol, referenced by a name, that has previously been exported, using sipExportSymbol(), by another module.

Parameter:name – the name of the symbol.
Returns:the value of the symbol. NULL is returned if there is no such symbol.
sipIntTypeClassMap

This C structure is used with sipMapIntToClass() to define a mapping between integer based RTTI and generated type objects. The structure elements are as follows.

int typeInt
The integer RTTI.
sipWrapperType **pyType.
A pointer to the corresponding generated type object.

Note

This is deprecated from SIP v4.8.

int sipIsAPIEnabled(const char *name, int from, int to)

New in version 4.9.

This checks to see if the current version number of an API falls within a given range. See Managing Incompatible APIs for more detail.

Parameters:
  • name – the name of the API.
  • from – the lower bound of the range. For the API to be enabled its version number must be greater than or equal to from. If from is 0 then this check isn’t made.
  • to – the upper bound of the range. For the API to be enabled its version number must be less than to. If to is 0 then this check isn’t made.
Returns:

a non-zero value if the API is enabled.
unsigned long sipLong_AsUnsignedLong(PyObject *obj)
This function is a thin wrapper around PyLong_AsUnsignedLong() that works around a bug in Python v2.3.x and earlier when converting integer objects.
void *sipMalloc(size_t nbytes)

This allocates an area of memory on the heap using the Python PyMem_Malloc() function. The memory is freed by calling sipFree().

Parameter:nbytes – the number of bytes to allocate.
Returns:the memory address. If there was an error then NULL is returned and a Python exception raised.
sipWrapperType *sipMapIntToClass(int type, const sipIntTypeClassMap *map, int maplen)

This can be used in %ConvertToSubClassCode code as a convenient way of converting integer based RTTI to the corresponding generated type object.

Parameters:
  • type – the integer RTTI.
  • map – the table of known RTTI and the corresponding type objects (see sipIntTypeClassMap). The entries in the table must be sorted in ascending order of RTTI.
  • maplen – the number of entries in the table.
Returns:

the corresponding type object, or NULL if type wasn’t in map.

Note

This is deprecated from SIP v4.8.

sipWrapperType *sipMapStringToClass(char *type, const sipStringTypeClassMap *map, int maplen)

This can be used in %ConvertToSubClassCode code as a convenient way of converting '\0' terminated string based RTTI to the corresponding generated type object.

Parameters:
  • type – the string RTTI.
  • map – the table of known RTTI and the corresponding type objects (see sipStringTypeClassMap). The entries in the table must be sorted in ascending order of RTTI.
  • maplen – the number of entries in the table.
Returns:

the corresponding type object, or NULL if type wasn’t in map.

Note

This is deprecated from SIP v4.8.

int sipParseResult(int *iserr, PyObject *method, PyObject *result, const char *format, ...)

This converts a Python object (usually returned by a method) to C/C++ based on a format string and associated values in a similar way to the Python PyArg_ParseTuple() function.

Parameters:
  • iserr – if this is not NULL then the location it points to is set to a non-zero value if there was an error.
  • method – the Python method that returned result.
  • result – the Python object returned by method.
  • format – the format string.
Returns:

0 if there was no error. Otherwise a negative value is returned, and an exception raised.

This is normally called by handwritten code specified with the %VirtualCatcherCode directive with method being the supplied sipMethod and result being the value returned by sipCallMethod().

If format begins and ends with parentheses then result must be a Python tuple and the rest of format is applied to the tuple contents.

In the following description the first letter is the format character, the entry in parentheses is the Python object type that the format character will convert, and the entry in brackets are the types of the C/C++ values to be passed.

ae (object) [char *]
Convert a Python string-like object of length 1 to a C/C++ char according to the encoding e. e can either be A for ASCII, L for Latin-1, or 8 for UTF-8. For Python v2 the object may be either a string or a tqunicode object that can be encoded. For Python v3 the object may either be a bytes object or a string object that can be encoded. An object that supports the buffer protocol may also be used.
b (integer) [bool *]
Convert a Python integer to a C/C++ bool.
c (string/bytes) [char *]
Convert a Python v2 string object or a Python v3 bytes object of length 1 to a C/C++ char.
d (float) [double *]
Convert a Python floating point number to a C/C++ double.
e (integer) [enum *]
Convert a Python integer to an anonymous C/C++ enum.
f (float) [float *]
Convert a Python floating point number to a C/C++ float.
g (string/bytes) [const char **, SIP_SSIZE_T *]
Convert a Python v2 string object or a Python v3 bytes object to a C/C++ character array and its length. If the Python object is Py_None then the array and length are NULL and zero respectively.
h (integer) [short *]
Convert a Python integer to a C/C++ short.
i (integer) [int *]
Convert a Python integer to a C/C++ int.
l (long) [long *]
Convert a Python long to a C/C++ long.
m (long) [unsigned long *]
Convert a Python long to a C/C++ unsigned long.
n (long) [long long *]
Convert a Python long to a C/C++ long long.
o (long) [unsigned long long *]
Convert a Python long to a C/C++ unsigned long long.
s (string/bytes) [const char **]

Convert a Python v2 string object or a Python v3 bytes object to a C/C++ '\0' terminated string. If the Python object is Py_None then the string is NULL.

Note

This is deprecated from SIP v4.8. Instead you should use B.

t (long) [unsigned short *]
Convert a Python long to a C/C++ unsigned short.
u (long) [unsigned int *]
Convert a Python long to a C/C++ unsigned int.
w (tqunicode/string) [wchar_t *]
Convert a Python v2 string or tqunicode object or a Python v3 string object of length 1 to a C/C++ wide character.
x (tqunicode/string) [wchar_t **]
Convert a Python v2 string or tqunicode object or a Python v3 string object to a C/C++ L'\0' terminated wide character string. If the Python object is Py_None then the string is NULL.
Ae (object) [int, const char **]
Convert a Python string-like object to a C/C++ '\0' terminated string according to the encoding e. e can either be A for ASCII, L for Latin-1, or 8 for UTF-8. If the Python object is Py_None then the string is NULL. The integer uniquely identifies the object in the context defined by the S format character and allows an extra reference to the object to be kept to ensure that the string remains valid. For Python v2 the object may be either a string or a tqunicode object that can be encoded. For Python v3 the object may either be a bytes object or a string object that can be encoded. An object that supports the buffer protocol may also be used.
B (string/bytes) [int, const char **]
Convert a Python v2 string object or a Python v3 bytes object to a C/C++ '\0' terminated string. If the Python object is Py_None then the string is NULL. The integer uniquely identifies the object in the context defined by the S format character and allows an extra reference to the object to be kept to ensure that the string remains valid.
Cf (wrapped class) [sipWrapperType *, int *, void **]

Convert a Python object to a C structure or a C++ class instance and return its state as described in sipConvertToInstance(). f is a combination of the following flags encoded as an ASCII character by adding 0 to the combined value:

0x01 disallows the conversion of Py_None to NULL

0x02 implements the Factory and TransferBack
annotations
0x04 suppresses the return of the state of the returned C/C++
instance. Note that the int * used to return the state is not passed if this flag is specified.

Note

This is deprecated from SIP v4.8. Instead you should use Hf.

Df (wrapped instance) [const sipTypeDef *, int *, void **]

Convert a Python object to a C structure, C++ class or mapped type instance and return its state as described in sipConvertToType(). f is a combination of the following flags encoded as an ASCII character by adding 0 to the combined value:

0x01 disallows the conversion of Py_None to NULL

0x02 implements the Factory and TransferBack
annotations
0x04 suppresses the return of the state of the returned C/C++
instance. Note that the int * used to return the state is not passed if this flag is specified.

Note

This is deprecated from SIP v4.10.1. Instead you should use Hf.

E (wrapped enum) [PyTypeObject *, enum *]

Convert a Python named enum type to the corresponding C/C++ enum.

Note

This is deprecated from SIP v4.8. Instead you should use F.

F (wrapped enum) [sipTypeDef *, enum *]
Convert a Python named enum type to the corresponding C/C++ enum.
G (tqunicode/string) [wchar_t **, SIP_SSIZE_T *]
Convert a Python v2 string or tqunicode object or a Python v3 string object to a C/C++ wide character array and its length. If the Python object is Py_None then the array and length are NULL and zero respectively.
Hf (wrapped instance) [const sipTypeDef *, int *, void **]

Convert a Python object to a C structure, C++ class or mapped type instance as described in sipConvertToType(). f is a combination of the following flags encoded as an ASCII character by adding 0 to the combined value:

0x01 disallows the conversion of Py_None to NULL

0x02 implements the Factory and TransferBack
annotations

0x04 returns a copy of the C/C++ instance.

N (object) [PyTypeObject *, :PyObject **]
A Python object is checked to see if it is a certain type and then returned without any conversions. The reference count is incremented. The Python object may be Py_None.
O (object) [PyObject **]
A Python object is returned without any conversions. The reference count is incremented.
S [sipSimpleWrapper *]
This format character, if used, must be the first. It is used with other format characters to define a context and doesn’t itself convert an argument.
T (object) [PyTypeObject *, PyObject **]
A Python object is checked to see if it is a certain type and then returned without any conversions. The reference count is incremented. The Python object may not be Py_None.
V (sip.voidptr) [void *]
Convert a Python sip.voidptr object to a C/C++ void *.
Z (object) []
Check that a Python object is Py_None. No value is returned.
int sipRegisterAttributeGetter(const sipTypeDef *td, sipAttrGetterFunc getter)

This registers a handler that will called just before SIP needs to get an attribute from a wrapped type’s dictionary for the first time. The handler must then populate the type’s dictionary with any lazy attributes.

Parameters:
  • td – the optional generated type structure that determines which types the handler will be called for.
  • getter – the handler function.
Returns:

0 if there was no error, otherwise -1 is returned.

If td is not NULL then the handler will only be called for types with that type or that are sub-classed from it. Otherwise the handler will be called for all types.

A handler has the following signature.

int handler(const sipTypeDef *td, PyObject *dict)

td is the generated type definition of the type whose dictionary is to be populated.

dict is the dictionary to be populated.

0 if there was no error, otherwise -1 is returned.

See the section Lazy Type Attributes for more details.

int sipRegisterPyType(PyTypeObject *type)

This registers a Python type object that can be used as the meta-type or super-type of a wrapped C++ type.

Parameter:type – the type object.
Returns:0 if there was no error, otherwise -1 is returned.

See the section Types and Meta-types for more details.

void sipReleaseInstance(void *cpp, sipWrapperType *type, int state)

This destroys a wrapped C/C++ instance if it was a temporary instance. It is called after a call to either sipConvertToInstance() or sipForceConvertToInstance().

Parameters:
  • cpp – the C/C++ instance.
  • type – the type’s generated type object.
  • state – describes the state of the C/C++ instance.

Note

This is deprecated from SIP v4.8. Instead you should use sipReleaseType().

void sipReleaseMappedType(void *cpp, const sipMappedType *mt, int state)

This destroys a wrapped C/C++ mapped type if it was a temporary instance. It is called after a call to either sipConvertToMappedType() or sipForceConvertToMappedType().

Parameters:
  • cpp – the C/C++ instance.
  • mt – the opaque structure returned by sipFindMappedType().
  • state – describes the state of the C/C++ instance.

Note

This is deprecated from SIP v4.8. Instead you should use sipReleaseType().

void sipReleaseType(void *cpp, const sipTypeDef *td, int state)

This destroys a wrapped C/C++ or mapped type instance if it was a temporary instance. It is called after a call to either sipConvertToType() or sipForceConvertToType().

Parameters:
  • cpp – the C/C++ instance.
  • td – the type’s generated type structure.
  • state – describes the state of the C/C++ instance.
const char *sipResolveTypedef(const char *name)

This returns the value of a C/C++ typedef.

Parameter:name – the name of the typedef.
Returns:the value of the typedef or NULL if there was no such typedef.
sipSimpleWrapper

This is a C structure that represents a Python wrapped instance whose type is sip.simplewrapper. It is an extension of the PyObject structure and so may be safely cast to it.

PyObject *user
This can be used for any purpose by handwritten code and will automatically be garbage collected at the appropriate time.
PyTypeObject *sipSimpleWrapper_Type
This is the type of a sipSimpleWrapper structure and is the C implementation of sip.simplewrapper. It may be safely cast to sipWrapperType.
sipStringTypeClassMap

This C structure is used with sipMapStringToClass() to define a mapping between '\0' terminated string based RTTI and Generated Type Objects. The structure elements are as follows.

char *typeString
The '\0' terminated string RTTI.
sipWrapperType **pyType.
A pointer to the corresponding generated type object.

Note

This is deprecated from SIP v4.8.

void sipTransferBack(PyObject *obj)

This transfers ownership of a Python wrapped instance to Python (see Ownership of Objects).

Parameter:obj – the wrapped instance.

In addition, any association of the instance with regard to the cyclic garbage collector with another instance is removed.

void sipTransferBreak(PyObject *obj)

Any association of a Python wrapped instance with regard to the cyclic garbage collector with another instance is removed. Ownership of the instance should be with C++.

Parameter:obj – the wrapped instance.
void sipTransferTo(PyObject *obj, PyObject *owner)

This transfers ownership of a Python wrapped instance to C++ (see Ownership of Objects).

Parameters:
  • obj – the wrapped instance.
  • owner – an optional wrapped instance that obj becomes associated with with regard to the cyclic garbage collector. If owner is NULL then no such association is made. If owner is the same value as obj then any reference cycles involving obj can never be detected or broken by the cyclic garbage collector. Responsibility for calling the C++ instance’s destructor is always transfered to C++.
PyTypeObject *sipTypeAsPyTypeObject(sipTypeDef *td)

This returns a pointer to the Python type object that SIP creates for a generated type structure.

Parameter:td – the type structure.
Returns:the Python type object. If the type structure refers to a mapped type then NULL will be returned.

If the type structure refers to a C structure or C++ class then the Python type object may be safely cast to a sipWrapperType.

const sipTypeDef *sipTypeFromPyTypeObject(PyTypeObject *py_type)

This returns the generated type structure for a Python type object.

Parameter:py_type – the Python type object.
Returns:the type structure or NULL if the Python type object doesn’t correspond to a type structure.
int sipTypeIsClass(sipTypeDef *td)

This checks if a generated type structure refers to a C structure or C++ class.

Parameter:td – the type structure.
Returns:a non-zero value if the type structure refers to a structure or class.
int sipTypeIsEnum(sipTypeDef *td)

This checks if a generated type structure refers to a named enum.

Parameter:td – the type structure.
Returns:a non-zero value if the type structure refers to an enum.
int sipTypeIsMapped(sipTypeDef *td)

This checks if a generated type structure refers to a mapped type.

Parameter:td – the type structure.
Returns:a non-zero value if the type structure refers to a mapped type.
int sipTypeIsNamespace(sipTypeDef *td)

This checks if a generated type structure refers to a C++ namespace.

Parameter:td – the type structure.
Returns:a non-zero value if the type structure refers to a namespace.
const char *sipTypeName(const sipTypeDef *td)

This returns the C/C++ name of a wrapped type.

Parameter:td – the type’s generated type structure.
Returns:the name of the C/C++ type.
const sipTypeDef *sipTypeScope(const sipTypeDef *td)

This returns the generated type structure of the enclosing scope of another generated type structure.

Parameter:td – the type structure.
Returns:the type structure of the scope or NULL if the type has no scope.
PyTypeObject *sipVoidPtr_Type
This is the type of a PyObject structure that is used to wrap a void *.
sipWrapper
This is a C structure that represents a Python wrapped instance whose type is sip.wrapper. It is an extension of the sipSimpleWrapper and PyObject structures and so may be safely cast to both.
int sipWrapper_Check(PyObject *obj)

This checks if a Python object is a wrapped instance.

Parameter:obj – the Python object.
Returns:a non-zero value if the Python object is a wrapped instance.

Note

This is deprecated from SIP v4.8. Instead you should use the following:

PyObject_TypeCheck(obj, sipWrapper_Type)
PyTypeObject *sipWrapper_Type
This is the type of a sipWrapper structure and is the C implementation of sip.wrapper. It may be safely cast to sipWrapperType.
sipWrapperType
This is a C structure that represents a SIP generated type object. It is an extension of the PyTypeObject structure (which is itself an extension of the PyObject structure) and so may be safely cast to PyTypeObject (and PyObject).
PyTypeObject *sipWrapperType_Type
This is the type of a sipWrapperType structure and is the C implementation of sip.wrappertype.

Generated Type Structures

SIP generates an opaque type structure for each C structure, C++ class, C++ namespace, named enum or mapped type being wrapped. These are sipTypeDef structures and are used extensively by the SIP API.

The names of these structure are prefixed by sipType_.

For those structures that correspond to C structures, C++ classes, C++ namespaces or named enums the remaining part of the name is the fully qualified name of the structure, class, namespace or enum name. Any :: scope separators are replaced by an underscore. For example, the type object for class Klass is sipType_Klass.

For those structure that correspond to mapped types the remaining part of the name is generated by SIP. The only way for handwritten code to obtain a pointer to a structure for a mapped type is to use sipFindType().

The type structures of all imported types are available to handwritten code.

Generated Type Objects

SIP generates a sipWrapperType type object for each C structure or C++ class being wrapped.

These objects are named with the structure or class name prefixed by sipClass_. For example, the type object for class Klass is sipClass_Klass.

Note

Using these names is deprecated from SIP v4.8. Instead use the corresponding generated type structure (see Generated Type Structures) and sipTypeAsPyTypeObject().

Generated Named Enum Type Objects

SIP generates a type object for each named enum being wrapped. These are PyTypeObject structures. (Anonymous enums are wrapped as Python integers.)

These objects are named with the fully qualified enum name (i.e. including any enclosing scope) prefixed by sipEnum_. For example, the type object for enum Enum defined in class Klass is sipEnum_Klass_Enum.

Note

Using these names is deprecated from SIP v4.8. Instead use the corresponding generated type structure (see Generated Type Structures) and sipTypeAsPyTypeObject().

Generated Derived Classes

For most C++ classes being wrapped SIP generates a derived class with the same name prefixed by sip. For example, the derived class for class Klass is sipKlass.

If a C++ class doesn’t have any virtual or protected methods in it or any of it’s super-class hierarchy, or does not emit any TQt signals, then a derived class is not generated.

Most of the time handwritten code should ignore the derived classes. The only exception is that handwritten constructor code specified using the %MethodCode directive should call the derived class’s constructor (which has the same C++ signature) rather then the wrapped class’s constructor.

Generated Exception Objects

SIP generates a Python object for each exception defined with the %Exception directive.

These objects are named with the fully qualified exception name (i.e. including any enclosing scope) prefixed by sipException_. For example, the type object for enum Except defined in class Klass is sipException_Klass_Except.

The objects of all imported exceptions are available to handwritten code.

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