libraries/pyshapelib/dbflibmodule.c

#include "pyshapelib_common.h"

/* --- DBFFile ------------------------------------------------------------------------------------------------------- */

typedef struct {
        PyObject_HEAD
        DBFHandle handle;
} DBFFileObject;


/* allocator 
*/
static PyObject* dbffile_new(PyTypeObject* type, PyObject* args, PyObject* kwds)
{
        DBFFileObject* self;    
        self = (DBFFileObject*) type->tp_alloc(type, 0);
        self->handle = NULL;
        return (PyObject*) self;
}


/* deallocator
*/
static void dbffile_dealloc(DBFFileObject* self)
{
        DBFClose(self->handle);
        self->handle = NULL;
        self->ob_type->tp_free((PyObject*)self);
}


/* constructor
*/
static int dbffile_init(DBFFileObject* self, PyObject* args, PyObject* kwds)
{
        char* file;
        char* mode = "rb";
        static char *kwlist[] = {"name", "mode", NULL};
        if (!PyArg_ParseTupleAndKeywords(args, kwds, "et|s:__init__", kwlist, 
                Py_FileSystemDefaultEncoding, &file, &mode)) return -1;
        
        self->handle = DBFOpen(file, mode);     
        if (!self->handle)
        {
                PyErr_SetFromErrnoWithFilename(PyExc_IOError, file);
        }

        PyMem_Free(file);
        return self->handle ? 0 : -1;
}


static PyObject* dbffile_close(DBFFileObject* self)
{
        DBFClose(self->handle);
        self->handle = NULL;
        Py_RETURN_NONE;
}


static PyObject* dbffile_field_count(DBFFileObject* self)
{
        return PyInt_FromLong((long)DBFGetFieldCount(self->handle));
}


static PyObject* dbffile_record_count(DBFFileObject* self)
{
        return PyInt_FromLong((long)DBFGetRecordCount(self->handle));
}


static PyObject* dbffile_field_info(DBFFileObject* self, PyObject* args)
{
        char field_name[12];
        int field, width = 0, decimals = 0, field_type;
        
        if (!PyArg_ParseTuple(args, "i:field_info", &field)) return NULL;
        
        field_name[0] = '\0';
        field_type = DBFGetFieldInfo(self->handle, field, field_name, &width, &decimals);
        
        return Py_BuildValue("isii", field_type, field_name, width, decimals);
}


static PyObject* dbffile_add_field(DBFFileObject* self, PyObject* args)
{
        char* name;
        int type, width, decimals;
        int field;
        
        if (!PyArg_ParseTuple(args, "siii:add_field", &name, &type, &width, &decimals)) return NULL;
        
        field = DBFAddField(self->handle, name, (DBFFieldType)type, width, decimals);
        
        if (field < 0)
        {
                PyErr_SetString(PyExc_ValueError, "Failed to add field due to inappropriate field definition");
                return NULL;
        }
        return PyInt_FromLong((long)field);
}


/* Read one attribute from the dbf handle and return it as a new python object
*
* If an error occurs, set the appropriate Python exception and return
* NULL.
*
* Assume that the values of the record and field arguments are valid.
* The name argument will be passed to DBFGetFieldInfo as is and should
* thus be either NULL or a pointer to an array of at least 12 chars
*/
static PyObject* do_read_attribute(DBFHandle handle, int record, int field, char * name)
{
        int type, width;
        const char* temp;
        type = DBFGetFieldInfo(handle, field, name, &width, NULL);
        
        /* For strings NULL and the empty string are indistinguishable
        * in DBF files. We prefer empty strings instead for backwards
        * compatibility reasons because older wrapper versions returned
        * emtpy strings as empty strings.
        */
        if (type != FTString && DBFIsAttributeNULL(handle, record, field))
        {
                Py_RETURN_NONE;
        }
        else
        {
                switch (type)
                {
                case FTString:
                        temp = DBFReadStringAttribute(handle, record, field);
                        if (temp) return PyString_FromString(temp);

                case FTInteger:
                        return PyInt_FromLong((long)DBFReadIntegerAttribute(handle, record, field));

                case FTDouble:
                        return PyFloat_FromDouble(DBFReadDoubleAttribute(handle, record, field));
                        
                case FTLogical:
                        temp = DBFReadLogicalAttribute(handle, record, field);
                        if (temp)
                        {
                                switch (temp[0])
                                {
                                case 'F':
                                case 'N':
                                        Py_RETURN_FALSE;
                                case 'T':
                                case 'Y':
                                        Py_RETURN_TRUE;
                                }
                        }
                        break;

                default:
                        PyErr_Format(PyExc_TypeError, "Invalid field data type %d", type);
                        return NULL;
                }
        }
        
        PyErr_Format(PyExc_IOError,     "Can't read value for row %d column %d", record, field);
        return NULL;
}    


/* the read_attribute method. Return the value of the given record and
* field as a python object of the appropriate type.
*/
static PyObject* dbffile_read_attribute(DBFFileObject* self, PyObject* args)
{
        int record, field;

        if (!PyArg_ParseTuple(args, "ii:read_field", &record, &field)) return NULL;
        
        if (record < 0 || record >= DBFGetRecordCount(self->handle))
        {
                PyErr_Format(PyExc_ValueError,
                                "record index %d out of bounds (record count: %d)",
                                record, DBFGetRecordCount(self->handle));
                return NULL;
        }

        if (field < 0 || field >= DBFGetFieldCount(self->handle))
        {
                PyErr_Format(PyExc_ValueError,
                                "field index %d out of bounds (field count: %d)",
                                field, DBFGetFieldCount(self->handle));
                return NULL;
        }

        return do_read_attribute(self->handle, record, field, NULL);
}


/* the read_record method. Return the record record as a dictionary with
* whose keys are the names of the fields, and their values as the
* appropriate Python type.
*/
static PyObject* dbffile_read_record(DBFFileObject* self, PyObject* args)
{
        int record;
        int num_fields;
        int i;
        char name[12];
        PyObject *dict;
        PyObject *value = NULL;

        if (!PyArg_ParseTuple(args, "i:read_record", &record)) return NULL;

        if (record < 0 || record >= DBFGetRecordCount(self->handle))
        {
                PyErr_Format(PyExc_ValueError,
                        "record index %d out of bounds (record count: %d)",
                        record, DBFGetRecordCount(self->handle));
                return NULL;
        }

        dict = PyDict_New();
        if (!dict) return NULL;
        
        num_fields = DBFGetFieldCount(self->handle);
        for (i = 0; i < num_fields; i++)
        {
                value = do_read_attribute(self->handle, record, i, name);
                if (!value || PyDict_SetItemString(dict, name, value) < 0) goto fail;
                Py_DECREF(value);
                value = NULL;
        }

        return dict;

fail:
        Py_XDECREF(value);
        Py_DECREF(dict);
        return NULL;
}


/* write a single field of a record. */
static int do_write_field(DBFHandle handle, int record, int field, int type, PyObject* value)
{
        char * string_value;
        int int_value;
        double double_value;
        int logical_value;

        if (value == Py_None)
        {
                if (DBFWriteNULLAttribute(handle, record, field)) return 1;
        }
        else
        {
                switch (type)
                {
                case FTString:
                        string_value = PyString_AsString(value);
                        if (!string_value) return 0;
                        if (DBFWriteStringAttribute(handle, record, field, string_value)) return 1;
                        break;

                case FTInteger:
                        int_value = PyInt_AsLong(value);
                        if (int_value == -1 && PyErr_Occurred()) return 0;
                        if (DBFWriteIntegerAttribute(handle, record, field, int_value)) return 1;
                        break;

                case FTDouble:
                        double_value = PyFloat_AsDouble(value);
                        if (double_value == -1 && PyErr_Occurred()) return 0;
                        if (DBFWriteDoubleAttribute(handle, record, field, double_value)) return 1;
                        break;
                        
                case FTLogical:
                        logical_value = PyObject_IsTrue(value);
                        if (logical_value == -1) return 0;
                        if (DBFWriteLogicalAttribute(handle, record, field, logical_value ? 'T' : 'F')) return 1;
                        break;

                default:
                        PyErr_Format(PyExc_TypeError, "Invalid field data type %d", type);
                        return 0;
                }
        }

        PyErr_Format(PyExc_IOError,     "can't write field %d of record %d", field, record);
        return 0;
}


static PyObject* dbffile_write_field(DBFFileObject* self, PyObject* args)
{
        int record, field;
        PyObject* value;
        int type;

        if (!PyArg_ParseTuple(args, "iiO:write_field", &record, &field, &value)) return NULL;
        
        if (field < 0 || field >= DBFGetFieldCount(self->handle))
        {
                PyErr_Format(PyExc_ValueError,
                                "field index %d out of bounds (field count: %d)",
                                field, DBFGetFieldCount(self->handle));
                return NULL;
        }

        type = DBFGetFieldInfo(self->handle, field, NULL, NULL, NULL);
        if (!do_write_field(self->handle, record, field, type, value)) return NULL;
        Py_RETURN_NONE;
}


static PyObject* dbffile_write_record(DBFFileObject* self, PyObject* args)
{
        int record;
        PyObject* record_object;
        int i, num_fields;
        
        int type;
        char name[12];
        PyObject* value = NULL;
        
        if (!PyArg_ParseTuple(args, "iO:write_record", &record, &record_object)) return NULL;
        
        num_fields = DBFGetFieldCount(self->handle);
        
        /* mimic ShapeFile functionality where id = -1 means appending */
        if (record == -1)
        {
                record = num_fields;
        }

        if (PySequence_Check(record_object))
        {
                /* It's a sequence object. Iterate through all items in the
                * sequence and write them to the appropriate field.
                */
                if (PySequence_Length(record_object) != num_fields)
                {
                        PyErr_SetString(PyExc_TypeError, "record must have one item for each field");
                        return NULL;
                }
                for (i = 0; i < num_fields; ++i)
                {
                        type = DBFGetFieldInfo(self->handle, i, NULL, NULL, NULL); 
                        value = PySequence_GetItem(record_object, i);
                        if (!value) return NULL;
                        if (!do_write_field(self->handle, record, i, type, value)) 
                        {
                                Py_DECREF(value);
                                return NULL;
                        }
                        Py_DECREF(value);
                }
        }
        else
        {
                /* It's a dictionary-like object. Iterate over the names of the
                * known fields and write the corresponding item
                */
                for (i = 0; i < num_fields; ++i)
                {
                        name[0] = '\0';
                        type = DBFGetFieldInfo(self->handle, i, name, NULL, NULL);
                        value = PyDict_GetItemString(record_object, name);
                        if (value && !do_write_field(self->handle, record, i, type, value)) return NULL;
                }
        }
        
        return PyInt_FromLong((long)record);
}


static PyObject* dbffile_repr(DBFFileObject* self)
{
        /* TODO: it would be nice to do something like "dbflib.DBFFile(filename, mode)" instead */
        return PyString_FromFormat("<dbflib.DBFFile object at %p>", self->handle);
}


/* The commit method implementation
*
* The method relies on the DBFUpdateHeader method which is not
* available in shapelib <= 1.2.10.  setup.py defines
* HAVE_UPDATE_HEADER's value depending on whether the function is
* available in the shapelib version the code is compiled with.
*/
#if HAVE_UPDATE_HEADER
static PyObject* dbffile_commit(DBFFileObject* self)
{
        DBFUpdateHeader(self->handle);
        Py_RETURN_NONE;
}
#endif


static struct PyMethodDef dbffile_methods[] = 
{
        {"close", (PyCFunction)dbffile_close, METH_NOARGS, 
                "close() -> None\n\n"
                "closes DBFFile"},
        {"field_count", (PyCFunction)dbffile_field_count, METH_NOARGS, 
                "field_count() -> integer\n\n"
                "returns number of fields currently defined"},
        {"record_count", (PyCFunction)dbffile_record_count, METH_NOARGS, 
                "record_count() -> integer\n\n"
                "returns number of records that currently exist"},
        {"field_info", (PyCFunction)dbffile_field_info, METH_VARARGS,
                "field_info(field_index) -> (type, name, width, decimals)\n\n"
                "returns info of a field as a tuple with:\n"
                "- type: the type of the field corresponding to the integer value of one "
                " of the constants FTString, FTInteger, ...\n"
                "- name: the name of the field as a string\n"
                "- width: the width of the field as a number of characters\n"
                "- decimals: the number of decimal digits" },
        {"add_field", (PyCFunction)dbffile_add_field, METH_VARARGS,
                "add_field(type, name, width, decimals) -> field_index\n\n"
                "adds a new field and returns field index if successful\n"
                "- type: the type of the field corresponding to the integer value of one "
                " of the constants FTString, FTInteger, ...\n"
                "- name: the name of the field as a string\n"
                "- width: the width of the field as a number of characters\n"
                "- decimals: the number of decimal digits" },
        {"read_attribute", (PyCFunction)dbffile_read_attribute, METH_VARARGS, 
                "read_attribute(record_index, field_index) -> value\n\n"
                "returns the value of one field of a record"},
        {"read_record", (PyCFunction)dbffile_read_record, METH_VARARGS, 
                "read_record(record_index) -> dict\n\n"
                "returns an entire record as a dictionary of field names and values"},
        {"write_field", (PyCFunction)dbffile_write_field, METH_VARARGS, 
                "write_field(record_index, field_index, new_value)\n"
                "writes a single field of a record"},
        {"write_record", (PyCFunction)dbffile_write_record, METH_VARARGS, 
                "write_record(record_index, record) -> record_index\n\n"
                "Writes an entire record as a dict or a sequence, and return index of record\n"
                "Record can either be a dictionary in which case the keys are used as field names, "
                "or a sequence that must have an item for every field (length = field_count())"},
#if HAVE_UPDATE_HEADER
        {"commit", (PyCFunction)dbffile_read_record, METH_NOARGS, 
                "commit() -> None"},
#endif
        {NULL}
};


static struct PyGetSetDef dbffile_getsetters[] = 
{
        {NULL}
};


static PyTypeObject DBFFileType = PYSHAPELIB_DEFINE_TYPE(DBFFileObject, dbffile, "shapelib.DBFFile", 0);


/* --- dbflib -------------------------------------------------------------------------------------------------------- */

static PyObject* dbflib_open(PyObject* module, PyObject* args)
{
        return PyObject_CallObject((PyObject*)&DBFFileType, args);
}


static PyObject* dbflib_create(PyObject* module, PyObject* args)
{
        char* file;
        DBFFileObject* result;
        
        if (!PyArg_ParseTuple(args, "et:create", Py_FileSystemDefaultEncoding, &file)) return NULL;
        
        result = PyObject_New(DBFFileObject, &DBFFileType);
        if (!result)
        {
                return PyErr_NoMemory();
        }
        
        result->handle = DBFCreate(file);
        if (!result->handle)
        {
                PyObject_Del((PyObject*)result);
                PyErr_SetString(PyExc_RuntimeError, "Failed to create DBFFile");
                return NULL;
        }
        
        return (PyObject*) result;
}


static struct PyMethodDef dbflib_methods[] = 
{
        {"open", (PyCFunction)dbflib_open, METH_VARARGS, 
                "open(name [, mode]) -> DBFFile\n\n"
                "opens a DBFFile" },
        {"create", (PyCFunction)dbflib_create, METH_VARARGS, 
                "create(name) -> DBFFile\n\n"
                "create a DBFFile" },
        {NULL}
};


PyMODINIT_FUNC initdbflib(void)
{
        PyObject* module = Py_InitModule("dbflib", dbflib_methods);
        if (!module) return;
        
        PYSHAPELIB_ADD_TYPE(DBFFileType, "DBFFile");
        
        PYSHAPELIB_ADD_CONSTANT(FTString);
        PYSHAPELIB_ADD_CONSTANT(FTInteger);
        PYSHAPELIB_ADD_CONSTANT(FTDouble);
        PYSHAPELIB_ADD_CONSTANT(FTLogical);
        PYSHAPELIB_ADD_CONSTANT(FTInvalid);
        PyModule_AddIntConstant(module, "_have_commit", HAVE_UPDATE_HEADER);
}
1	#include "pyshapelib_common.h"
2
3	/* --- DBFFile ------------------------------------------------------------------------------------------------------- */
4
5	typedef struct {
6	PyObject_HEAD
7	DBFHandle handle;
8	} DBFFileObject;
9
10
11
12	/* allocator
13	*/
14	static PyObject* dbffile_new(PyTypeObject* type, PyObject* args, PyObject* kwds)
15	{
16	DBFFileObject* self;
17	self = (DBFFileObject*) type->tp_alloc(type, 0);
18	self->handle = NULL;
19	return (PyObject*) self;
20	}
21
22
23
24	/* deallocator
25	*/
26	static void dbffile_dealloc(DBFFileObject* self)
27	{
28	DBFClose(self->handle);
29	self->handle = NULL;
30	self->ob_type->tp_free((PyObject*)self);
31	}
32
33
34
35	/* constructor
36	*/
37	static int dbffile_init(DBFFileObject* self, PyObject* args, PyObject* kwds)
38	{
39	char* file;
40	char* mode = "rb";
41	static char *kwlist[] = {"name", "mode", NULL};
42	if (!PyArg_ParseTupleAndKeywords(args, kwds, "et\|s:__init__", kwlist,
43	Py_FileSystemDefaultEncoding, &file, &mode)) return -1;
44
45	self->handle = DBFOpen(file, mode);
46	if (!self->handle)
47	{
48	PyErr_SetFromErrnoWithFilename(PyExc_IOError, file);
49	}
50
51	PyMem_Free(file);
52	return self->handle ? 0 : -1;
53	}
54
55
56
57	static PyObject* dbffile_close(DBFFileObject* self)
58	{
59	DBFClose(self->handle);
60	self->handle = NULL;
61	Py_RETURN_NONE;
62	}
63
64
65
66	static PyObject* dbffile_field_count(DBFFileObject* self)
67	{
68	return PyInt_FromLong((long)DBFGetFieldCount(self->handle));
69	}
70
71
72
73	static PyObject* dbffile_record_count(DBFFileObject* self)
74	{
75	return PyInt_FromLong((long)DBFGetRecordCount(self->handle));
76	}
77
78
79
80	static PyObject* dbffile_field_info(DBFFileObject* self, PyObject* args)
81	{
82	char field_name[12];
83	int field, width = 0, decimals = 0, field_type;
84
85	if (!PyArg_ParseTuple(args, "i:field_info", &field)) return NULL;
86
87	field_name[0] = '\0';
88	field_type = DBFGetFieldInfo(self->handle, field, field_name, &width, &decimals);
89
90	return Py_BuildValue("isii", field_type, field_name, width, decimals);
91	}
92
93
94
95	static PyObject* dbffile_add_field(DBFFileObject* self, PyObject* args)
96	{
97	char* name;
98	int type, width, decimals;
99	int field;
100
101	if (!PyArg_ParseTuple(args, "siii:add_field", &name, &type, &width, &decimals)) return NULL;
102
103	field = DBFAddField(self->handle, name, (DBFFieldType)type, width, decimals);
104
105	if (field < 0)
106	{
107	PyErr_SetString(PyExc_ValueError, "Failed to add field due to inappropriate field definition");
108	return NULL;
109	}
110	return PyInt_FromLong((long)field);
111	}
112
113
114
115	/* Read one attribute from the dbf handle and return it as a new python object
116	*
117	* If an error occurs, set the appropriate Python exception and return
118	* NULL.
119	*
120	* Assume that the values of the record and field arguments are valid.
121	* The name argument will be passed to DBFGetFieldInfo as is and should
122	* thus be either NULL or a pointer to an array of at least 12 chars
123	*/
124	static PyObject* do_read_attribute(DBFHandle handle, int record, int field, char * name)
125	{
126	int type, width;
127	const char* temp;
128	type = DBFGetFieldInfo(handle, field, name, &width, NULL);
129
130	/* For strings NULL and the empty string are indistinguishable
131	* in DBF files. We prefer empty strings instead for backwards
132	* compatibility reasons because older wrapper versions returned
133	* emtpy strings as empty strings.
134	*/
135	if (type != FTString && DBFIsAttributeNULL(handle, record, field))
136	{
137	Py_RETURN_NONE;
138	}
139	else
140	{
141	switch (type)
142	{
143	case FTString:
144	temp = DBFReadStringAttribute(handle, record, field);
145	if (temp) return PyString_FromString(temp);
146
147	case FTInteger:
148	return PyInt_FromLong((long)DBFReadIntegerAttribute(handle, record, field));
149
150	case FTDouble:
151	return PyFloat_FromDouble(DBFReadDoubleAttribute(handle, record, field));
152
153	case FTLogical:
154	temp = DBFReadLogicalAttribute(handle, record, field);
155	if (temp)
156	{
157	switch (temp[0])
158	{
159	case 'F':
160	case 'N':
161	Py_RETURN_FALSE;
162	case 'T':
163	case 'Y':
164	Py_RETURN_TRUE;
165	}
166	}
167	break;
168
169	default:
170	PyErr_Format(PyExc_TypeError, "Invalid field data type %d", type);
171	return NULL;
172	}
173	}
174
175	PyErr_Format(PyExc_IOError, "Can't read value for row %d column %d", record, field);
176	return NULL;
177	}
178
179
180
181	/* the read_attribute method. Return the value of the given record and
182	* field as a python object of the appropriate type.
183	*/
184	static PyObject* dbffile_read_attribute(DBFFileObject* self, PyObject* args)
185	{
186	int record, field;
187
188	if (!PyArg_ParseTuple(args, "ii:read_field", &record, &field)) return NULL;
189
190	if (record < 0 \|\| record >= DBFGetRecordCount(self->handle))
191	{
192	PyErr_Format(PyExc_ValueError,
193	"record index %d out of bounds (record count: %d)",
194	record, DBFGetRecordCount(self->handle));
195	return NULL;
196	}
197
198	if (field < 0 \|\| field >= DBFGetFieldCount(self->handle))
199	{
200	PyErr_Format(PyExc_ValueError,
201	"field index %d out of bounds (field count: %d)",
202	field, DBFGetFieldCount(self->handle));
203	return NULL;
204	}
205
206	return do_read_attribute(self->handle, record, field, NULL);
207	}
208
209
210
211	/* the read_record method. Return the record record as a dictionary with
212	* whose keys are the names of the fields, and their values as the
213	* appropriate Python type.
214	*/
215	static PyObject* dbffile_read_record(DBFFileObject* self, PyObject* args)
216	{
217	int record;
218	int num_fields;
219	int i;
220	char name[12];
221	PyObject *dict;
222	PyObject *value = NULL;
223
224	if (!PyArg_ParseTuple(args, "i:read_record", &record)) return NULL;
225
226	if (record < 0 \|\| record >= DBFGetRecordCount(self->handle))
227	{
228	PyErr_Format(PyExc_ValueError,
229	"record index %d out of bounds (record count: %d)",
230	record, DBFGetRecordCount(self->handle));
231	return NULL;
232	}
233
234	dict = PyDict_New();
235	if (!dict) return NULL;
236
237	num_fields = DBFGetFieldCount(self->handle);
238	for (i = 0; i < num_fields; i++)
239	{
240	value = do_read_attribute(self->handle, record, i, name);
241	if (!value \|\| PyDict_SetItemString(dict, name, value) < 0) goto fail;
242	Py_DECREF(value);
243	value = NULL;
244	}
245
246	return dict;
247
248	fail:
249	Py_XDECREF(value);
250	Py_DECREF(dict);
251	return NULL;
252	}
253
254
255
256	/* write a single field of a record. */
257	static int do_write_field(DBFHandle handle, int record, int field, int type, PyObject* value)
258	{
259	char * string_value;
260	int int_value;
261	double double_value;
262	int logical_value;
263
264	if (value == Py_None)
265	{
266	if (DBFWriteNULLAttribute(handle, record, field)) return 1;
267	}
268	else
269	{
270	switch (type)
271	{
272	case FTString:
273	string_value = PyString_AsString(value);
274	if (!string_value) return 0;
275	if (DBFWriteStringAttribute(handle, record, field, string_value)) return 1;
276	break;
277
278	case FTInteger:
279	int_value = PyInt_AsLong(value);
280	if (int_value == -1 && PyErr_Occurred()) return 0;
281	if (DBFWriteIntegerAttribute(handle, record, field, int_value)) return 1;
282	break;
283
284	case FTDouble:
285	double_value = PyFloat_AsDouble(value);
286	if (double_value == -1 && PyErr_Occurred()) return 0;
287	if (DBFWriteDoubleAttribute(handle, record, field, double_value)) return 1;
288	break;
289
290	case FTLogical:
291	logical_value = PyObject_IsTrue(value);
292	if (logical_value == -1) return 0;
293	if (DBFWriteLogicalAttribute(handle, record, field, logical_value ? 'T' : 'F')) return 1;
294	break;
295
296	default:
297	PyErr_Format(PyExc_TypeError, "Invalid field data type %d", type);
298	return 0;
299	}
300	}
301
302	PyErr_Format(PyExc_IOError, "can't write field %d of record %d", field, record);
303	return 0;
304	}
305
306
307
308	static PyObject* dbffile_write_field(DBFFileObject* self, PyObject* args)
309	{
310	int record, field;
311	PyObject* value;
312	int type;
313
314	if (!PyArg_ParseTuple(args, "iiO:write_field", &record, &field, &value)) return NULL;
315
316	if (field < 0 \|\| field >= DBFGetFieldCount(self->handle))
317	{
318	PyErr_Format(PyExc_ValueError,
319	"field index %d out of bounds (field count: %d)",
320	field, DBFGetFieldCount(self->handle));
321	return NULL;
322	}
323
324	type = DBFGetFieldInfo(self->handle, field, NULL, NULL, NULL);
325	if (!do_write_field(self->handle, record, field, type, value)) return NULL;
326	Py_RETURN_NONE;
327	}
328
329
330
331	static PyObject* dbffile_write_record(DBFFileObject* self, PyObject* args)
332	{
333	int record;
334	PyObject* record_object;
335	int i, num_fields;
336
337	int type;
338	char name[12];
339	PyObject* value = NULL;
340
341	if (!PyArg_ParseTuple(args, "iO:write_record", &record, &record_object)) return NULL;
342
343	num_fields = DBFGetFieldCount(self->handle);
344
345	/* mimic ShapeFile functionality where id = -1 means appending */
346	if (record == -1)
347	{
348	record = num_fields;
349	}
350
351	if (PySequence_Check(record_object))
352	{
353	/* It's a sequence object. Iterate through all items in the
354	* sequence and write them to the appropriate field.
355	*/
356	if (PySequence_Length(record_object) != num_fields)
357	{
358	PyErr_SetString(PyExc_TypeError, "record must have one item for each field");
359	return NULL;
360	}
361	for (i = 0; i < num_fields; ++i)
362	{
363	type = DBFGetFieldInfo(self->handle, i, NULL, NULL, NULL);
364	value = PySequence_GetItem(record_object, i);
365	if (!value) return NULL;
366	if (!do_write_field(self->handle, record, i, type, value))
367	{
368	Py_DECREF(value);
369	return NULL;
370	}
371	Py_DECREF(value);
372	}
373	}
374	else
375	{
376	/* It's a dictionary-like object. Iterate over the names of the
377	* known fields and write the corresponding item
378	*/
379	for (i = 0; i < num_fields; ++i)
380	{
381	name[0] = '\0';
382	type = DBFGetFieldInfo(self->handle, i, name, NULL, NULL);
383	value = PyDict_GetItemString(record_object, name);
384	if (value && !do_write_field(self->handle, record, i, type, value)) return NULL;
385	}
386	}
387
388	return PyInt_FromLong((long)record);
389	}
390
391
392
393	static PyObject* dbffile_repr(DBFFileObject* self)
394	{
395	/* TODO: it would be nice to do something like "dbflib.DBFFile(filename, mode)" instead */
396	return PyString_FromFormat("<dbflib.DBFFile object at %p>", self->handle);
397	}
398
399
400
401	/* The commit method implementation
402	*
403	* The method relies on the DBFUpdateHeader method which is not
404	* available in shapelib <= 1.2.10. setup.py defines
405	* HAVE_UPDATE_HEADER's value depending on whether the function is
406	* available in the shapelib version the code is compiled with.
407	*/
408	#if HAVE_UPDATE_HEADER
409	static PyObject* dbffile_commit(DBFFileObject* self)
410	{
411	DBFUpdateHeader(self->handle);
412	Py_RETURN_NONE;
413	}
414	#endif
415
416
417
418	static struct PyMethodDef dbffile_methods[] =
419	{
420	{"close", (PyCFunction)dbffile_close, METH_NOARGS,
421	"close() -> None\n\n"
422	"closes DBFFile"},
423	{"field_count", (PyCFunction)dbffile_field_count, METH_NOARGS,
424	"field_count() -> integer\n\n"
425	"returns number of fields currently defined"},
426	{"record_count", (PyCFunction)dbffile_record_count, METH_NOARGS,
427	"record_count() -> integer\n\n"
428	"returns number of records that currently exist"},
429	{"field_info", (PyCFunction)dbffile_field_info, METH_VARARGS,
430	"field_info(field_index) -> (type, name, width, decimals)\n\n"
431	"returns info of a field as a tuple with:\n"
432	"- type: the type of the field corresponding to the integer value of one "
433	" of the constants FTString, FTInteger, ...\n"
434	"- name: the name of the field as a string\n"
435	"- width: the width of the field as a number of characters\n"
436	"- decimals: the number of decimal digits" },
437	{"add_field", (PyCFunction)dbffile_add_field, METH_VARARGS,
438	"add_field(type, name, width, decimals) -> field_index\n\n"
439	"adds a new field and returns field index if successful\n"
440	"- type: the type of the field corresponding to the integer value of one "
441	" of the constants FTString, FTInteger, ...\n"
442	"- name: the name of the field as a string\n"
443	"- width: the width of the field as a number of characters\n"
444	"- decimals: the number of decimal digits" },
445	{"read_attribute", (PyCFunction)dbffile_read_attribute, METH_VARARGS,
446	"read_attribute(record_index, field_index) -> value\n\n"
447	"returns the value of one field of a record"},
448	{"read_record", (PyCFunction)dbffile_read_record, METH_VARARGS,
449	"read_record(record_index) -> dict\n\n"
450	"returns an entire record as a dictionary of field names and values"},
451	{"write_field", (PyCFunction)dbffile_write_field, METH_VARARGS,
452	"write_field(record_index, field_index, new_value)\n"
453	"writes a single field of a record"},
454	{"write_record", (PyCFunction)dbffile_write_record, METH_VARARGS,
455	"write_record(record_index, record) -> record_index\n\n"
456	"Writes an entire record as a dict or a sequence, and return index of record\n"
457	"Record can either be a dictionary in which case the keys are used as field names, "
458	"or a sequence that must have an item for every field (length = field_count())"},
459	#if HAVE_UPDATE_HEADER
460	{"commit", (PyCFunction)dbffile_read_record, METH_NOARGS,
461	"commit() -> None"},
462	#endif
463	{NULL}
464	};
465
466
467
468	static struct PyGetSetDef dbffile_getsetters[] =
469	{
470	{NULL}
471	};
472
473
474
475	static PyTypeObject DBFFileType = PYSHAPELIB_DEFINE_TYPE(DBFFileObject, dbffile, "shapelib.DBFFile", 0);
476
477
478
479	/* --- dbflib -------------------------------------------------------------------------------------------------------- */
480
481	static PyObject* dbflib_open(PyObject* module, PyObject* args)
482	{
483	return PyObject_CallObject((PyObject*)&DBFFileType, args);
484	}
485
486
487
488	static PyObject* dbflib_create(PyObject* module, PyObject* args)
489	{
490	char* file;
491	DBFFileObject* result;
492
493	if (!PyArg_ParseTuple(args, "et:create", Py_FileSystemDefaultEncoding, &file)) return NULL;
494
495	result = PyObject_New(DBFFileObject, &DBFFileType);
496	if (!result)
497	{
498	return PyErr_NoMemory();
499	}
500
501	result->handle = DBFCreate(file);
502	if (!result->handle)
503	{
504	PyObject_Del((PyObject*)result);
505	PyErr_SetString(PyExc_RuntimeError, "Failed to create DBFFile");
506	return NULL;
507	}
508
509	return (PyObject*) result;
510	}
511
512
513
514	static struct PyMethodDef dbflib_methods[] =
515	{
516	{"open", (PyCFunction)dbflib_open, METH_VARARGS,
517	"open(name [, mode]) -> DBFFile\n\n"
518	"opens a DBFFile" },
519	{"create", (PyCFunction)dbflib_create, METH_VARARGS,
520	"create(name) -> DBFFile\n\n"
521	"create a DBFFile" },
522	{NULL}
523	};
524
525
526
527	PyMODINIT_FUNC initdbflib(void)
528	{
529	PyObject* module = Py_InitModule("dbflib", dbflib_methods);
530	if (!module) return;
531
532	PYSHAPELIB_ADD_TYPE(DBFFileType, "DBFFile");
533
534	PYSHAPELIB_ADD_CONSTANT(FTString);
535	PYSHAPELIB_ADD_CONSTANT(FTInteger);
536	PYSHAPELIB_ADD_CONSTANT(FTDouble);
537	PYSHAPELIB_ADD_CONSTANT(FTLogical);
538	PYSHAPELIB_ADD_CONSTANT(FTInvalid);
539	PyModule_AddIntConstant(module, "_have_commit", HAVE_UPDATE_HEADER);
540	}
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