Add support for Python 3

Installation of the missing py_compile module was factored out into a
standalone script which is only compatible with Python 2.

Author: westphahl

Adafruit_I2C.py

@@ -4,8 +4,8 @@
 
 # ===========================================================================
 # Adafruit_I2C Class
-# Adafruit_I2C.py is essentially a fork of the Adafruit Raspberry Pi I2C module. 
-# Any pull requests for this module should be directed to the following, and I 
+# Adafruit_I2C.py is essentially a fork of the Adafruit Raspberry Pi I2C module.
+# Any pull requests for this module should be directed to the following, and I
 # can pull them. I'd rather not deviate from the original:
 # https://github.com/adafruit/Adafruit-Raspberry-Pi-Python-Code/tree/master/Adafruit_I2C
 # ===========================================================================
@@ -28,59 +28,59 @@ def reverseByteOrder(self, data):
     return val
 
   def errMsg(self):
-    print "Error accessing 0x%02X: Check your I2C address" % self.address
+    print("Error accessing 0x%02X: Check your I2C address" % self.address)
     return -1
 
   def write8(self, reg, value):
     "Writes an 8-bit value to the specified register/address"
     try:
       self.bus.write_byte_data(self.address, reg, value)
       if self.debug:
-        print "I2C: Wrote 0x%02X to register 0x%02X" % (value, reg)
-    except IOError, err:
+        print("I2C: Wrote 0x%02X to register 0x%02X" % (value, reg))
+    except IOError as err:
       return self.errMsg()
 
   def write16(self, reg, value):
     "Writes a 16-bit value to the specified register/address pair"
     try:
       self.bus.write_word_data(self.address, reg, value)
       if self.debug:
-        print ("I2C: Wrote 0x%02X to register pair 0x%02X,0x%02X" %
+        print("I2C: Wrote 0x%02X to register pair 0x%02X,0x%02X" %
          (value, reg, reg+1))
-    except IOError, err:
+    except IOError as err:
       return self.errMsg()
 
   def writeList(self, reg, list):
     "Writes an array of bytes using I2C format"
     try:
       if self.debug:
-        print "I2C: Writing list to register 0x%02X:" % reg
-        print list
+        print("I2C: Writing list to register 0x%02X:" % reg)
+        print(list)
       self.bus.write_i2c_block_data(self.address, reg, list)
-    except IOError, err:
+    except IOError as err:
       return self.errMsg()
 
   def readList(self, reg, length):
     "Read a list of bytes from the I2C device"
     try:
       results = self.bus.read_i2c_block_data(self.address, reg, length)
       if self.debug:
-        print ("I2C: Device 0x%02X returned the following from reg 0x%02X" %
+        print("I2C: Device 0x%02X returned the following from reg 0x%02X" %
          (self.address, reg))
-        print results
+        print(results)
       return results
-    except IOError, err:
+    except IOError as err:
       return self.errMsg()
 
   def readU8(self, reg):
     "Read an unsigned byte from the I2C device"
     try:
       result = self.bus.read_byte_data(self.address, reg)
       if self.debug:
-        print ("I2C: Device 0x%02X returned 0x%02X from reg 0x%02X" %
+        print("I2C: Device 0x%02X returned 0x%02X from reg 0x%02X" %
          (self.address, result & 0xFF, reg))
       return result
-    except IOError, err:
+    except IOError as err:
       return self.errMsg()
 
   def readS8(self, reg):
@@ -89,35 +89,35 @@ def readS8(self, reg):
       result = self.bus.read_byte_data(self.address, reg)
       if result > 127: result -= 256
       if self.debug:
-        print ("I2C: Device 0x%02X returned 0x%02X from reg 0x%02X" %
+        print("I2C: Device 0x%02X returned 0x%02X from reg 0x%02X" %
          (self.address, result & 0xFF, reg))
       return result
-    except IOError, err:
+    except IOError as err:
       return self.errMsg()
 
   def readU16(self, reg):
     "Reads an unsigned 16-bit value from the I2C device"
     try:
       result = self.bus.read_word_data(self.address,reg)
       if (self.debug):
-        print "I2C: Device 0x%02X returned 0x%04X from reg 0x%02X" % (self.address, result & 0xFFFF, reg)
+        print("I2C: Device 0x%02X returned 0x%04X from reg 0x%02X" % (self.address, result & 0xFFFF, reg))
       return result
-    except IOError, err:
+    except IOError as err:
       return self.errMsg()
 
   def readS16(self, reg):
     "Reads a signed 16-bit value from the I2C device"
     try:
       result = self.bus.read_word_data(self.address,reg)
       if (self.debug):
-        print "I2C: Device 0x%02X returned 0x%04X from reg 0x%02X" % (self.address, result & 0xFFFF, reg)
+        print("I2C: Device 0x%02X returned 0x%04X from reg 0x%02X" % (self.address, result & 0xFFFF, reg))
       return result
-    except IOError, err:
+    except IOError as err:
       return self.errMsg()
 
 if __name__ == '__main__':
   try:
     bus = Adafruit_I2C(address=0)
-    print "Default I2C bus is accessible"
+    print("Default I2C bus is accessible")
   except:
-    print "Error accessing default I2C bus"
+    print("Error accessing default I2C bus")

fix_py_compile.py

@@ -0,0 +1,22 @@
+#!/usr/bin/env python2
+# Some Angstrom images are missing the py_compile module; get it if not
+# present:
+# Fix credit:https://github.com/alexanderhiam/PyBBIO/blob/master/setup.py
+import random, os
+python_lib_path = random.__file__.split('random')[0]
+if not os.path.exists(python_lib_path + 'py_compile.py'):
+  print "py_compile module missing; installing to %spy_compile.py" %\
+                                                          python_lib_path
+  import urllib2
+  url = "http://hg.python.org/cpython/raw-file/4ebe1ede981e/Lib/py_compile.py"
+  py_compile = urllib2.urlopen(url)
+  with open(python_lib_path+'py_compile.py', 'w') as f:
+    f.write(py_compile.read())
+  print "testing py_compile..."
+  try:
+    import py_compile
+    print "py_compile installed successfully"
+  except Exception, e:
+    print "*py_compile install failed, could not import"
+    print "*Exception raised:"
+    raise e

setup.py

@@ -1,25 +1,3 @@
-# Some Angstrom images are missing the py_compile module; get it if not
-# present:
-# Fix credit:https://github.com/alexanderhiam/PyBBIO/blob/master/setup.py
-import random, os
-python_lib_path = random.__file__.split('random')[0]
-if not os.path.exists(python_lib_path + 'py_compile.py'):
-  print "py_compile module missing; installing to %spy_compile.py" %\
-                                                          python_lib_path
-  import urllib2
-  url = "http://hg.python.org/cpython/raw-file/4ebe1ede981e/Lib/py_compile.py"
-  py_compile = urllib2.urlopen(url)
-  with open(python_lib_path+'py_compile.py', 'w') as f:
-    f.write(py_compile.read())
-  print "testing py_compile..."
-  try:
-    import py_compile
-    print "py_compile installed successfully"
-  except Exception, e:
-    print "*py_compile install failed, could not import"
-    print "*Exception raised:"
-    raise e
-
 try:
     from overlays import builder
     builder.compile()
@@ -35,7 +13,6 @@
                'Operating System :: POSIX :: Linux',
                'License :: OSI Approved :: MIT License',
                'Intended Audience :: Developers',
-               'Programming Language :: Python :: 2.6',
                'Programming Language :: Python :: 2.7',
                'Programming Language :: Python :: 3',
                'Topic :: Software Development',
@@ -54,7 +31,7 @@
       classifiers      = classifiers,
       packages         = find_packages(),
       py_modules       = ['Adafruit_I2C'],
-      ext_modules      = [Extension('Adafruit_BBIO.GPIO', ['source/py_gpio.c', 'source/event_gpio.c', 'source/constants.c', 'source/common.c'], extra_compile_args=['-Wno-format-security']), 
+      ext_modules      = [Extension('Adafruit_BBIO.GPIO', ['source/py_gpio.c', 'source/event_gpio.c', 'source/constants.c', 'source/common.c'], extra_compile_args=['-Wno-format-security']),
                           Extension('Adafruit_BBIO.PWM', ['source/py_pwm.c', 'source/c_pwm.c', 'source/constants.c', 'source/common.c'], extra_compile_args=['-Wno-format-security']),
                           Extension('Adafruit_BBIO.ADC', ['source/py_adc.c', 'source/c_adc.c', 'source/constants.c', 'source/common.c'], extra_compile_args=['-Wno-format-security']),
                           Extension('Adafruit_BBIO.SPI', ['source/spimodule.c', 'source/constants.c', 'source/common.c'], extra_compile_args=['-Wno-format-security']),

source/spimodule.c

@@ -33,6 +33,12 @@
 #include <sys/ioctl.h>
 #include "common.h"
 
+#if PY_MAJOR_VERSION < 3
+#	define PyLong_AS_LONG(val) PyInt_AS_LONG(val)
+#	define PyLong_AsLong(val) PyInt_AsLong(val)
+#	define PyLong_Check(val) PyInt_Check(val)
+#endif
+
 PyDoc_STRVAR(SPI_module_doc,
 	"This module defines an object type that allows SPI transactions\n"
 	"on hosts running the Linux kernel. The host kernel must have SPI\n"
@@ -94,7 +100,7 @@ SPI_dealloc(SPI *self)
 	PyObject *ref = SPI_close(self);
 	Py_XDECREF(ref);
 
-	self->ob_type->tp_free((PyObject *)self);
+	Py_TYPE(self)->tp_free((PyObject *)self);
 }
 
 #define MAXPATH 16
@@ -131,11 +137,11 @@ SPI_writebytes(SPI *self, PyObject *args)
 
 	for (ii = 0; ii < len; ii++) {
 		PyObject *val = PyList_GET_ITEM(list, ii);
-		if (!PyInt_Check(val)) {
+		if (!PyLong_Check(val)) {
 			PyErr_SetString(PyExc_TypeError, wrmsg);
 			return NULL;
 		}
-		buf[ii] = (__u8)PyInt_AS_LONG(val);
+		buf[ii] = (__u8)PyLong_AS_LONG(val);
 	}
 
 	status = write(self->fd, &buf[0], len);
@@ -237,14 +243,14 @@ SPI_xfer(SPI *self, PyObject *args)
 
 	for (ii = 0; ii < len; ii++) {
 		PyObject *val = PyList_GET_ITEM(list, ii);
-		if (!PyInt_Check(val)) {
+		if (!PyLong_Check(val)) {
 			free(txbuf);
 			free(rxbuf);
 			free(xferptr);
 			PyErr_SetString(PyExc_TypeError, wrmsg);
 			return NULL;
 		}
-		txbuf[ii] = (__u8)PyInt_AS_LONG(val);
+		txbuf[ii] = (__u8)PyLong_AS_LONG(val);
 		xferptr[ii].tx_buf = (unsigned long)&txbuf[ii];
 		xferptr[ii].rx_buf = (unsigned long)&rxbuf[ii];
 		xferptr[ii].len = 1;
@@ -315,13 +321,13 @@ SPI_xfer2(SPI *self, PyObject *args)
 
 	for (ii = 0; ii < len; ii++) {
 		PyObject *val = PyList_GET_ITEM(list, ii);
-		if (!PyInt_Check(val)) {
+		if (!PyLong_Check(val)) {
 			free(txbuf);
 			free(rxbuf);
 			PyErr_SetString(PyExc_TypeError, msg);
 			return NULL;
 		}
-		txbuf[ii] = (__u8)PyInt_AS_LONG(val);
+		txbuf[ii] = (__u8)PyLong_AS_LONG(val);
 	}
 
 	xfer.tx_buf = (unsigned long)txbuf;
@@ -447,13 +453,13 @@ SPI_set_mode(SPI *self, PyObject *val, void *closure)
 			"Cannot delete attribute");
 		return -1;
 	}
-	else if (!PyInt_Check(val)) {
+	else if (!PyLong_Check(val)) {
 		PyErr_SetString(PyExc_TypeError,
 			"The mode attribute must be an integer");
 		return -1;
 	}
 
-	mode = PyInt_AsLong(val);
+	mode = PyLong_AsLong(val);
 
 	if ( mode > 3 ) {
 		PyErr_SetString(PyExc_TypeError,
@@ -601,13 +607,13 @@ SPI_set_bpw(SPI *self, PyObject *val, void *closure)
 			"Cannot delete attribute");
 		return -1;
 	}
-	else if (!PyInt_Check(val)) {
+	else if (!PyLong_Check(val)) {
 		PyErr_SetString(PyExc_TypeError,
 			"The bpw attribute must be an integer");
 		return -1;
 	}
 
-	bits = PyInt_AsLong(val);
+	bits = PyLong_AsLong(val);
 
         if (bits < 8 || bits > 16) {
 		PyErr_SetString(PyExc_TypeError,
@@ -642,13 +648,13 @@ SPI_set_msh(SPI *self, PyObject *val, void *closure)
 			"Cannot delete attribute");
 		return -1;
 	}
-	else if (!PyInt_Check(val)) {
+	else if (!PyLong_Check(val)) {
 		PyErr_SetString(PyExc_TypeError,
 			"The msh attribute must be an integer");
 		return -1;
 	}
 
-	msh = PyInt_AsLong(val);
+	msh = PyLong_AsLong(val);
 	// DAW - 8/12/12 - removed limitation on SPI speed
 	// if (8000000 < msh) {
 		// PyErr_SetString(PyExc_TypeError,
@@ -793,8 +799,7 @@ static PyMethodDef SPI_methods[] = {
 };
 
 static PyTypeObject SPI_type = {
-	PyObject_HEAD_INIT(NULL)
-	0,				/* ob_size */
+	PyVarObject_HEAD_INIT(NULL, 0)
 	"SPI",			/* tp_name */
 	sizeof(SPI),			/* tp_basicsize */
 	0,				/* tp_itemsize */
@@ -838,20 +843,47 @@ static PyMethodDef SPI_module_methods[] = {
 	{NULL}
 };
 
+#if PY_MAJOR_VERSION >= 3
+static struct PyModuleDef moduledef = {
+	PyModuleDef_HEAD_INIT,
+	"SPI",               /* m_name */
+	SPI_module_doc,      /* m_doc */
+	-1,                  /* m_size */
+	SPI_module_methods,  /* m_methods */
+	NULL,                /* m_reload */
+	NULL,                /* m_traverse */
+	NULL,                /* m_clear */
+	NULL,                /* m_free */
+};
+#endif
+
 #ifndef PyMODINIT_FUNC	/* declarations for DLL import/export */
 #define PyMODINIT_FUNC void
 #endif
 PyMODINIT_FUNC
+#if PY_MAJOR_VERSION >= 3
+PyInit_SPI(void)
+#else
 initSPI(void)
+#endif
 {
 	PyObject* m;
 
 	if (PyType_Ready(&SPI_type) < 0)
 		return;
 
+#if PY_MAJOR_VERSION >= 3
+	m = PyModule_Create(&moduledef);
+#else
 	m = Py_InitModule3("SPI", SPI_module_methods, SPI_module_doc);
+#endif
+
 	Py_INCREF(&SPI_type);
 	PyModule_AddObject(m, "SPI", (PyObject *)&SPI_type);
+
+#if PY_MAJOR_VERSION >= 3
+	return m;
+#endif
 }