Added Python 3 support

README.md

@@ -3,6 +3,12 @@ tesserpy
 
 A Python API for Tesseract
 
+Requirements
+------------
+* Python >= 2.7 or >= 3.2
+* NumPy >= 1.6
+* Tesseract >= 3.02
+
 Building
 --------
 It's the usual distutils dance -- run `python setup.py` for more details.

compat.hpp

@@ -0,0 +1,14 @@
+/* Compatibility changes for compiling against Python 3.x */
+
+#if PY_MAJOR_VERSION >= 3
+#define IS_PY3K
+#define Py_TPFLAGS_HAVE_ITER 0
+#define PyInt_FromLong PyLong_FromLong
+#define PyString_FromString PyUnicode_FromString
+#if PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION >= 3
+#define PyString_AsString(STR) PyUnicode_AsUTF8((STR))
+#else
+/* XXX reference leak below */
+#define PyString_AsString(STR) PyBytes_AsString(PyUnicode_AsUTF8String((STR)))
+#endif
+#endif

setup.py

@@ -6,8 +6,9 @@
 import os
 
 kVersionBase = '0.1dev'
+kStringEncoding = 'utf-8'
 
-version = kVersionBase + subprocess.check_output(['git', 'describe', '--dirty', '--always'])
+version = kVersionBase + subprocess.check_output(['git', 'describe', '--dirty', '--always']).decode(kStringEncoding)
 
 setup(
 		name = 'tesserpy',

tesserpy.cpp

@@ -7,6 +7,7 @@
 #include <structmember.h>
 #include <tesseract/baseapi.h>
 #include <numpy/arrayobject.h>
+#include "compat.hpp"
 
 #pragma GCC diagnostic ignored "-Wwrite-strings"
 
@@ -556,9 +557,17 @@ static int PyTesseract_init(PyTesseract *self, PyObject *args, PyObject *kwargs)
 	tesseract::OcrEngineMode oem = tesseract::OEM_TESSERACT_ONLY;
 
 	static const char *kwlist[] = { "data_path", "language", "oem", NULL };
+#ifdef IS_PY3K
+	PyObject *py_datapath;
+	if (!PyArg_ParseTupleAndKeywords(args, kwargs, "O&|si", (char **)kwlist, PyUnicode_FSConverter, &py_datapath, &language, &oem)) {
+#else
 	if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s|si", (char **)kwlist, &datapath, &language, &oem)) {
+#endif
 		return -1;
 	}
+#ifdef IS_PY3K
+	datapath = PyBytes_AsString(py_datapath);
+#endif
 	self->page = NULL;
 	self->iterators = PyList_New(0);
 	int result = self->tess->Init(datapath, language, oem);
@@ -585,7 +594,7 @@ static PyObject* PyTesseract_clear(PyTesseract *self) {
 
 static int PyTesseract_setattr(PyTesseract *self, PyObject *attr, PyObject *py_value) {
 	// attribute name must be a string, but value will be converted with str()
-	char *name = PyString_AsString(attr);
+	const char *name = PyString_AsString(attr);
 	if (!name) {
 		PyErr_SetString(PyExc_TypeError, "Attribute name must be a string");
 		return -1;
@@ -597,7 +606,7 @@ static int PyTesseract_setattr(PyTesseract *self, PyObject *attr, PyObject *py_v
 		return -1;
 	}
 
-	char *value = PyString_AsString(py_value_str);
+	const char *value = PyString_AsString(py_value_str);
 	bool result = self->tess->SetVariable(name, value);
 	Py_CLEAR(py_value_str);
 	if (!result) {
@@ -614,7 +623,7 @@ static PyObject* PyTesseract_getattr(PyTesseract *self, PyObject *attr) {
 	}
 	PyErr_Clear();
 	// attribute name must be a string
-	char *name = PyString_AsString(attr);
+	const char *name = PyString_AsString(attr);
 	if (!name) {
 		PyErr_SetString(PyExc_TypeError, "Attribute name is not a string");
 		return NULL;
@@ -791,37 +800,67 @@ static PyResultIterator* PyTesseract_blocks(PyTesseract *self) {
 	return iterator;
 }
 
+typedef struct {
+	// This module has no state
+} PyModuleState;
+
 static PyMethodDef TesserPyMethods[] = {
 	{ NULL, NULL } // sentinel
 };
 
+#ifdef IS_PY3K
+#define INITERROR return NULL
+
+static struct PyModuleDef TesserPyModuleDef {
+	PyModuleDef_HEAD_INIT,
+	"tesserpy", // m_name
+	PyDoc_STR("A Python API for Tesseract"), // m_doc
+	sizeof(PyModuleState), // m_size
+	TesserPyMethods, // m_methods
+	NULL, // m_reload
+	NULL, // m_traverse
+	NULL, // m_clear
+	NULL // m_free
+};
+
+PyMODINIT_FUNC PyInit_tesserpy(void) {
+#else
+#define INITERROR return
+
 PyMODINIT_FUNC inittesserpy(void) {
+#endif
+
 	PyBoundingBox_Type.tp_new = PyType_GenericNew;
 	if (PyType_Ready(&PyBoundingBox_Type) < 0) {
-		return;
+		INITERROR;
 	}
 
 	PyPageInfo_Type.tp_new = PyType_GenericNew;
 	if (PyType_Ready(&PyPageInfo_Type) < 0) {
-		return;
+		INITERROR;
 	}
 
 	PyResult_Type.tp_new = PyType_GenericNew;
 	if (PyType_Ready(&PyResult_Type) < 0) {
-		return;
+		INITERROR;
 	}
 
 	if (PyType_Ready(&PyResultIterator_Type) < 0) {
-		return;
+		INITERROR;
 	}
 
 	if (PyType_Ready(&PyTesseract_Type) < 0) {
-		return;
+		INITERROR;
 	}
 
+#ifdef IS_PY3K
+	PyObject *module = PyModule_Create(&TesserPyModuleDef);
+#else
 	PyObject *module = Py_InitModule("tesserpy", TesserPyMethods);
+#endif
+
 	if (module == NULL) {
-		return;
+		INITERROR;
 	}
 
 	import_array();
@@ -884,4 +923,7 @@ PyMODINIT_FUNC inittesserpy(void) {
 	PyModule_AddIntConstant(module, "TEXTLINE_ORDER_LEFT_TO_RIGHT", tesseract::TEXTLINE_ORDER_LEFT_TO_RIGHT);
 	PyModule_AddIntConstant(module, "TEXTLINE_ORDER_RIGHT_TO_LEFT", tesseract::TEXTLINE_ORDER_RIGHT_TO_LEFT);
 	PyModule_AddIntConstant(module, "TEXTLINE_ORDER_TOP_TO_BOTTOM", tesseract::TEXTLINE_ORDER_TOP_TO_BOTTOM);
+#ifdef IS_PY3K
+	return module;
+#endif
 }