mapi/glapi: Use ElementTree instead of libxml2.

It is quite hard to meet the dependency of the libxml2 python bindings
outside Linux, and in particularly on MacOSX; whereas ElementTree is
part of Python's standard library.  ElementTree is more limited than
libxml2: no DTD verification, defaults from DTD, or XInclude support,
but none of these limitations is serious enough to justify using
libxml2.

In fact, it was easier to refactor the code to use ElementTree than to
try to get libxml2 python bindings.

In the process, gl_item_factory class was refactored so that there is
one method for each kind of object to be created, as it simplifies
things substantially.

I confirmed that precisely the same output is generated for GL/GLX/GLES.

v2: Remove m4/ax_python_module.m4 as suggested by Matt Turner.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

8 files changed, 141 insertions, 221 deletions

diff --git a/SConstruct b/SConstruct
index de735e9..0e10818 100644
--- a/SConstruct
+++ b/SConstruct
@@ -59,13 +59,6 @@ else:
 
 Help(opts.GenerateHelpText(env))
 
-# fail early for a common error on windows
-if env['gles']:
-    try:
-        import libxml2
-    except ImportError:
-        raise SCons.Errors.UserError, "GLES requires libxml2-python to build"
-
 #######################################################################
 # Environment setup
 
diff --git a/configure.ac b/configure.ac
index 97d7dc5..1e5e496 100644
--- a/configure.ac
+++ b/configure.ac
@@ -54,7 +54,6 @@ AM_PROG_CC_C_O
 AM_PROG_AS
 AC_CHECK_PROGS([MAKE], [gmake make])
 AC_CHECK_PROGS([PYTHON2], [python2 python])
-AX_PYTHON_MODULE([libxml2], [needed])
 AC_PROG_SED
 AC_PROG_MKDIR_P
 
diff --git a/docs/README.WIN32 b/docs/README.WIN32
index 0cd007c..c8759f6 100644
--- a/docs/README.WIN32
+++ b/docs/README.WIN32
@@ -36,17 +36,15 @@ Recipe
 Building on windows requires several open-source packages. These are
 steps that work as of this writing.
 
-1) install python 2.7
-2) install scons (latest)
-3) install mingw, flex, and bison
-4) install libxml2 from here: http://www.lfd.uci.edu/~gohlke/pythonlibs
-  get libxml2-python-2.9.1.win-amd64-py2.7.exe
-5) install pywin32 from here: http://www.lfd.uci.edu/~gohlke/pythonlibs
+- install python 2.7
+- install scons (latest)
+- install mingw, flex, and bison
+- install pywin32 from here: http://www.lfd.uci.edu/~gohlke/pythonlibs
   get pywin32-218.4.win-amd64-py2.7.exe
-6) install git
-7) download mesa from git
+- install git
+- download mesa from git
   see http://www.mesa3d.org/repository.html
-8) run scons
+- run scons
 
 General
 -------
diff --git a/docs/install.html b/docs/install.html
index 24492a7..5061ede 100644
--- a/docs/install.html
+++ b/docs/install.html
@@ -44,10 +44,6 @@ On Windows with MinGW, install flex and bison with:
 </li>
 <li>python - Python is needed for building the Gallium components.
 Version 2.6.4 or later should work.
-<br>
-<br>
-To build OpenGL ES 1.1 and 2.0 you'll also need
-<a href="http://xmlsoft.org/sources/win32/python/libxml2-python-2.7.7.win32-py2.7.exe">libxml2-python</a>.
 </li>
 </ul>
 
diff --git a/m4/ax_python_module.m4 b/m4/ax_python_module.m4
deleted file mode 100644
index 2e6670a..0000000
--- a/m4/ax_python_module.m4
+++ /dev/null
@@ -1,49 +0,0 @@
-# ===========================================================================
-#     http://www.gnu.org/software/autoconf-archive/ax_python_module.html
-# ===========================================================================
-#
-# SYNOPSIS
-#
-#   AX_PYTHON_MODULE(modname[, fatal])
-#
-# DESCRIPTION
-#
-#   Checks for Python module.
-#
-#   If fatal is non-empty then absence of a module will trigger an error.
-#
-# LICENSE
-#
-#   Copyright (c) 2008 Andrew Collier
-#
-#   Copying and distribution of this file, with or without modification, are
-#   permitted in any medium without royalty provided the copyright notice
-#   and this notice are preserved. This file is offered as-is, without any
-#   warranty.
-
-#serial 6
-
-AU_ALIAS([AC_PYTHON_MODULE], [AX_PYTHON_MODULE])
-AC_DEFUN([AX_PYTHON_MODULE],[
-    if test -z $PYTHON2;
-    then
-        PYTHON2="python"
-    fi
-    PYTHON_NAME=`basename $PYTHON2`
-    AC_MSG_CHECKING($PYTHON_NAME module: $1)
-	$PYTHON2 -c "import $1" 2>/dev/null
-	if test $? -eq 0;
-	then
-		AC_MSG_RESULT(yes)
-		eval AS_TR_CPP(HAVE_PYMOD_$1)=yes
-	else
-		AC_MSG_RESULT(no)
-		eval AS_TR_CPP(HAVE_PYMOD_$1)=no
-		#
-		if test -n "$2"
-		then
-			AC_MSG_ERROR(failed to find required module $1)
-			exit 1
-		fi
-	fi
-])
diff --git a/src/mapi/glapi/gen/glX_XML.py b/src/mapi/glapi/gen/glX_XML.py
index 03a35b7..12ff291 100644
--- a/src/mapi/glapi/gen/glX_XML.py
+++ b/src/mapi/glapi/gen/glX_XML.py
@@ -33,29 +33,27 @@ import sys, getopt, string
 class glx_item_factory(gl_XML.gl_item_factory):
     """Factory to create GLX protocol oriented objects derived from gl_item."""
 
-    def create_item(self, name, element, context):
-        if name == "function":
-            return glx_function(element, context)
-        elif name == "enum":
-            return glx_enum(element, context)
-        elif name == "api":
-            return glx_api(self)
-        else:
-            return gl_XML.gl_item_factory.create_item(self, name, element, context)
+    def create_function(self, element, context):
+        return glx_function(element, context)
+
+    def create_enum(self, element, context, category):
+        return glx_enum(element, context, category)
+
+    def create_api(self):
+        return glx_api(self)
 
 
 class glx_enum(gl_XML.gl_enum):
-    def __init__(self, element, context):
-        gl_XML.gl_enum.__init__(self, element, context)
+    def __init__(self, element, context, category):
+        gl_XML.gl_enum.__init__(self, element, context, category)
 
         self.functions = {}
 
-        child = element.children
-        while child:
-            if child.type == "element" and child.name == "size":
-                n = child.nsProp( "name", None )
-                c = child.nsProp( "count", None )
-                m = child.nsProp( "mode", None )
+        for child in element.getchildren():
+            if child.tag == "size":
+                n = child.get( "name" )
+                c = child.get( "count" )
+                m = child.get( "mode", "set" )
 
                 if not c:
                     c = self.default_count
@@ -70,8 +68,6 @@ class glx_enum(gl_XML.gl_enum):
                 if not self.functions.has_key(n):
                     self.functions[ n ] = [c, mode]
 
-            child = child.next
-
         return
 
 
@@ -120,10 +116,10 @@ class glx_function(gl_XML.gl_function):
         # appears after the function that it aliases.
 
         if not self.vectorequiv:
-            self.vectorequiv = element.nsProp("vectorequiv", None)
+            self.vectorequiv = element.get("vectorequiv")
 
 
-        name = element.nsProp("name", None)
+        name = element.get("name")
         if name == self.name:
             for param in self.parameters:
                 self.parameters_by_name[ param.name ] = param
@@ -135,12 +131,11 @@ class glx_function(gl_XML.gl_function):
                     self.counter_list.append(param.counter)
 
 
-        child = element.children
-        while child:
-            if child.type == "element" and child.name == "glx":
-                rop = child.nsProp( 'rop', None )
-                sop = child.nsProp( 'sop', None )
-                vop = child.nsProp( 'vendorpriv', None )
+        for child in element.getchildren():
+            if child.tag == "glx":
+                rop = child.get( 'rop' )
+                sop = child.get( 'sop' )
+                vop = child.get( 'vendorpriv' )
 
                 if rop:
                     self.glx_rop = int(rop)
@@ -152,12 +147,12 @@ class glx_function(gl_XML.gl_function):
                     self.glx_vendorpriv = int(vop)
                     self.glx_vendorpriv_names.append(name)
 
-                self.img_reset = child.nsProp( 'img_reset', None )
+                self.img_reset = child.get( 'img_reset' )
 
                 # The 'handcode' attribute can be one of 'true',
                 # 'false', 'client', or 'server'.
 
-                handcode = child.nsProp( 'handcode', None )
+                handcode = child.get( 'handcode', 'false' )
                 if handcode == "false":
                     self.server_handcode = 0
                     self.client_handcode = 0
@@ -179,8 +174,6 @@ class glx_function(gl_XML.gl_function):
                 self.reply_always_array   = gl_XML.is_attr_true( child, 'always_array' )
                 self.dimensions_in_reply  = gl_XML.is_attr_true( child, 'dimensions_in_reply' )
 
-            child = child.next
-
 
         # Do some validation of the GLX protocol information.  As
         # new tests are discovered, they should be added here.
diff --git a/src/mapi/glapi/gen/glX_proto_common.py b/src/mapi/glapi/gen/glX_proto_common.py
index 86d9189..ae2c2d5 100644
--- a/src/mapi/glapi/gen/glX_proto_common.py
+++ b/src/mapi/glapi/gen/glX_proto_common.py
@@ -32,18 +32,15 @@ import string
 class glx_proto_item_factory(glX_XML.glx_item_factory):
     """Factory to create GLX protocol oriented objects derived from gl_item."""
 
-    def create_item(self, name, element, context):
-        if name == "type":
-            return glx_proto_type(element, context)
-        else:
-            return glX_XML.glx_item_factory.create_item(self, name, element, context)
+    def create_type(self, element, context, category):
+        return glx_proto_type(element, context, category)
 
 
 class glx_proto_type(gl_XML.gl_type):
-    def __init__(self, element, context):
-        gl_XML.gl_type.__init__(self, element, context)
+    def __init__(self, element, context, category):
+        gl_XML.gl_type.__init__(self, element, context, category)
 
-        self.glx_name = element.nsProp( "glx_name", None )
+        self.glx_name = element.get( "glx_name" )
         return
 
 
diff --git a/src/mapi/glapi/gen/gl_XML.py b/src/mapi/glapi/gen/gl_XML.py
index 3bbc794..1a2bc2b 100644
--- a/src/mapi/glapi/gen/gl_XML.py
+++ b/src/mapi/glapi/gen/gl_XML.py
@@ -26,20 +26,19 @@
 #    Ian Romanick <idr@us.ibm.com>
 
 from decimal import Decimal
-import libxml2
+import xml.etree.ElementTree as ET
 import re, sys, string
+import os.path
 import typeexpr
 
 
 def parse_GL_API( file_name, factory = None ):
-    doc = libxml2.readFile( file_name, None, libxml2.XML_PARSE_XINCLUDE + libxml2.XML_PARSE_NOBLANKS + libxml2.XML_PARSE_DTDVALID + libxml2.XML_PARSE_DTDATTR + libxml2.XML_PARSE_DTDLOAD + libxml2.XML_PARSE_NOENT )
-    ret = doc.xincludeProcess()
 
     if not factory:
         factory = gl_item_factory()
 
-    api = factory.create_item( "api", None, None )
-    api.process_element( doc )
+    api = factory.create_api()
+    api.parse_file( file_name )
 
     # After the XML has been processed, we need to go back and assign
     # dispatch offsets to the functions that request that their offsets
@@ -51,12 +50,10 @@ def parse_GL_API( file_name, factory = None ):
             func.offset = api.next_offset;
             api.next_offset += 1
 
-    doc.freeDoc()
-
     return api
 
 
-def is_attr_true( element, name ):
+def is_attr_true( element, name, default = "false" ):
     """Read a name value from an element's attributes.
 
     The value read from the attribute list must be either 'true' or
@@ -64,7 +61,7 @@ def is_attr_true( element, name ):
     value is 'true', non-zero will be returned.  An exception will be
     raised for any other value."""
 
-    value = element.nsProp( name, None )
+    value = element.get( name, default )
     if value == "true":
         return 1
     elif value == "false":
@@ -254,8 +251,8 @@ class gl_print_base(object):
 
 
 def real_function_name(element):
-    name = element.nsProp( "name", None )
-    alias = element.nsProp( "alias", None )
+    name = element.get( "name" )
+    alias = element.get( "alias" )
 
     if alias:
         return alias
@@ -324,21 +321,22 @@ def create_parameter_string(parameters, include_names):
 
 
 class gl_item(object):
-    def __init__(self, element, context):
+    def __init__(self, element, context, category):
         self.context = context
-        self.name = element.nsProp( "name", None )
-        self.category = real_category_name( element.parent.nsProp( "name", None ) )
+        self.name = element.get( "name" )
+        self.category = real_category_name( category )
+
         return
 
 
 class gl_type( gl_item ):
-    def __init__(self, element, context):
-        gl_item.__init__(self, element, context)
-        self.size = int( element.nsProp( "size", None ), 0 )
+    def __init__(self, element, context, category):
+        gl_item.__init__(self, element, context, category)
+        self.size = int( element.get( "size" ), 0 )
 
         te = typeexpr.type_expression( None )
         tn = typeexpr.type_node()
-        tn.size = int( element.nsProp( "size", None ), 0 )
+        tn.size = int( element.get( "size" ), 0 )
         tn.integer = not is_attr_true( element, "float" )
         tn.unsigned = is_attr_true( element, "unsigned" )
         tn.pointer = is_attr_true( element, "pointer" )
@@ -354,11 +352,11 @@ class gl_type( gl_item ):
 
 
 class gl_enum( gl_item ):
-    def __init__(self, element, context):
-        gl_item.__init__(self, element, context)
-        self.value = int( element.nsProp( "value", None ), 0 )
+    def __init__(self, element, context, category):
+        gl_item.__init__(self, element, context, category)
+        self.value = int( element.get( "value" ), 0 )
 
-        temp = element.nsProp( "count", None )
+        temp = element.get( "count" )
         if not temp or temp == "?":
             self.default_count = -1
         else:
@@ -404,12 +402,12 @@ class gl_enum( gl_item ):
 
 class gl_parameter(object):
     def __init__(self, element, context):
-        self.name = element.nsProp( "name", None )
+        self.name = element.get( "name" )
 
-        ts = element.nsProp( "type", None )
+        ts = element.get( "type" )
         self.type_expr = typeexpr.type_expression( ts, context )
 
-        temp = element.nsProp( "variable_param", None )
+        temp = element.get( "variable_param" )
         if temp:
             self.count_parameter_list = temp.split( ' ' )
         else:
@@ -420,7 +418,7 @@ class gl_parameter(object):
         # statement will throw an exception, and the except block will
         # take over.
 
-        c = element.nsProp( "count", None )
+        c = element.get( "count" )
         try: 
             count = int(c)
             self.count = count
@@ -430,7 +428,7 @@ class gl_parameter(object):
             self.count = 0
             self.counter = c
 
-        self.count_scale = int(element.nsProp( "count_scale", None ))
+        self.count_scale = int(element.get( "count_scale", "1" ))
 
         elements = (count * self.count_scale)
         if elements == 1:
@@ -450,19 +448,19 @@ class gl_parameter(object):
 
         # Pixel data has special parameters.
 
-        self.width      = element.nsProp('img_width',  None)
-        self.height     = element.nsProp('img_height', None)
-        self.depth      = element.nsProp('img_depth',  None)
-        self.extent     = element.nsProp('img_extent', None)
+        self.width      = element.get('img_width')
+        self.height     = element.get('img_height')
+        self.depth      = element.get('img_depth')
+        self.extent     = element.get('img_extent')
 
-        self.img_xoff   = element.nsProp('img_xoff',   None)
-        self.img_yoff   = element.nsProp('img_yoff',   None)
-        self.img_zoff   = element.nsProp('img_zoff',   None)
-        self.img_woff   = element.nsProp('img_woff',   None)
+        self.img_xoff   = element.get('img_xoff')
+        self.img_yoff   = element.get('img_yoff')
+        self.img_zoff   = element.get('img_zoff')
+        self.img_woff   = element.get('img_woff')
 
-        self.img_format = element.nsProp('img_format', None)
-        self.img_type   = element.nsProp('img_type',   None)
-        self.img_target = element.nsProp('img_target', None)
+        self.img_format = element.get('img_format')
+        self.img_type   = element.get('img_type')
+        self.img_target = element.get('img_target')
 
         self.img_pad_dimensions = is_attr_true( element, 'img_pad_dimensions' )
         self.img_null_flag      = is_attr_true( element, 'img_null_flag' )
@@ -648,17 +646,17 @@ class gl_function( gl_item ):
 
 
     def process_element(self, element):
-        name = element.nsProp( "name", None )
-        alias = element.nsProp( "alias", None )
+        name = element.get( "name" )
+        alias = element.get( "alias" )
 
-        if is_attr_true(element, "static_dispatch"):
+        if is_attr_true(element, "static_dispatch", "true"):
             self.static_entry_points.append(name)
 
         self.entry_points.append( name )
 
         self.entry_point_api_map[name] = {}
         for api in ('es1', 'es2'):
-            version_str = element.nsProp(api, None)
+            version_str = element.get(api, 'none')
             assert version_str is not None
             if version_str != 'none':
                 version_decimal = Decimal(version_str)
@@ -667,15 +665,15 @@ class gl_function( gl_item ):
                         version_decimal < self.api_map[api]:
                     self.api_map[api] = version_decimal
 
-        exec_flavor = element.nsProp('exec', None)
+        exec_flavor = element.get('exec')
         if exec_flavor:
             self.exec_flavor = exec_flavor
 
-        deprecated = element.nsProp('deprecated', None)
+        deprecated = element.get('deprecated', 'none')
         if deprecated != 'none':
             self.deprecated = Decimal(deprecated)
 
-        if not is_attr_true(element, 'desktop'):
+        if not is_attr_true(element, 'desktop', 'true'):
             self.desktop = False
 
         if alias:
@@ -686,7 +684,7 @@ class gl_function( gl_item ):
             # Only try to set the offset when a non-alias entry-point
             # is being processed.
 
-            offset = element.nsProp( "offset", None )
+            offset = element.get( "offset" )
             if offset:
                 try:
                     o = int( offset )
@@ -712,16 +710,12 @@ class gl_function( gl_item ):
 
         parameters = []
         return_type = "void"
-        child = element.children
-        while child:
-            if child.type == "element":
-                if child.name == "return":
-                    return_type = child.nsProp( "type", None )
-                elif child.name == "param":
-                    param = self.context.factory.create_item( "parameter", child, self.context)
-                    parameters.append( param )
-
-            child = child.next
+        for child in element.getchildren():
+            if child.tag == "return":
+                return_type = child.get( "type", "void" )
+            elif child.tag == "param":
+                param = self.context.factory.create_parameter(child, self.context)
+                parameters.append( param )
 
 
         if self.initialized:
@@ -746,7 +740,7 @@ class gl_function( gl_item ):
                 if param.is_image():
                     self.images.append( param )
 
-        if element.children:
+        if element.getchildren():
             self.initialized = 1
             self.entry_point_parameters[name] = parameters
         else:
@@ -848,19 +842,20 @@ class gl_function( gl_item ):
 class gl_item_factory(object):
     """Factory to create objects derived from gl_item."""
 
-    def create_item(self, item_name, element, context):
-        if item_name == "function":
-            return gl_function(element, context)
-        if item_name == "type":
-            return gl_type(element, context)
-        elif item_name == "enum":
-            return gl_enum(element, context)
-        elif item_name == "parameter":
-            return gl_parameter(element, context)
-        elif item_name == "api":
-            return gl_api(self)
-        else:
-            return None
+    def create_function(self, element, context):
+        return gl_function(element, context)
+
+    def create_type(self, element, context, category):
+        return gl_type(element, context, category)
+
+    def create_enum(self, element, context, category):
+        return gl_enum(element, context, category)
+
+    def create_parameter(self, element, context):
+        return gl_parameter(element, context)
+
+    def create_api(self):
+        return gl_api(self)
 
 
 class gl_api(object):
@@ -903,66 +898,64 @@ class gl_api(object):
 
         self.functions_by_name = functions_by_name
 
-    def process_element(self, doc):
-        element = doc.children
-        while element.type != "element" or element.name != "OpenGLAPI":
-            element = element.next
 
-        if element:
-            self.process_OpenGLAPI(element)
-        return
+    def parse_file(self, file_name):
+        doc = ET.parse( file_name )
+        self.process_element(file_name, doc)
 
 
-    def process_OpenGLAPI(self, element):
-        child = element.children
-        while child:
-            if child.type == "element":
-                if child.name == "category":
-                    self.process_category( child )
-                elif child.name == "OpenGLAPI":
-                    self.process_OpenGLAPI( child )
+    def process_element(self, file_name, doc):
+        element = doc.getroot()
+        if element.tag == "OpenGLAPI":
+            self.process_OpenGLAPI(file_name, element)
+        return
+
 
-            child = child.next
+    def process_OpenGLAPI(self, file_name, element):
+        for child in element.getchildren():
+            if child.tag == "category":
+                self.process_category( child )
+            elif child.tag == "OpenGLAPI":
+                self.process_OpenGLAPI( file_name, child )
+            elif child.tag == '{http://www.w3.org/2001/XInclude}include':
+                href = child.get('href')
+                href = os.path.join(os.path.dirname(file_name), href)
+                self.parse_file(href)
 
         return
 
 
     def process_category(self, cat):
-        cat_name = cat.nsProp( "name", None )
-        cat_number = cat.nsProp( "number", None )
+        cat_name = cat.get( "name" )
+        cat_number = cat.get( "number" )
 
         [cat_type, key] = classify_category(cat_name, cat_number)
         self.categories[cat_type][key] = [cat_name, cat_number]
 
-        child = cat.children
-        while child:
-            if child.type == "element":
-                if child.name == "function":
-                    func_name = real_function_name( child )
-
-                    temp_name = child.nsProp( "name", None )
-                    self.category_dict[ temp_name ] = [cat_name, cat_number]
-
-                    if self.functions_by_name.has_key( func_name ):
-                        func = self.functions_by_name[ func_name ]
-                        func.process_element( child )
-                    else:
-                        func = self.factory.create_item( "function", child, self )
-                        self.functions_by_name[ func_name ] = func
+        for child in cat.getchildren():
+            if child.tag == "function":
+                func_name = real_function_name( child )
 
-                    if func.offset >= self.next_offset:
-                        self.next_offset = func.offset + 1
+                temp_name = child.get( "name" )
+                self.category_dict[ temp_name ] = [cat_name, cat_number]
 
+                if self.functions_by_name.has_key( func_name ):
+                    func = self.functions_by_name[ func_name ]
+                    func.process_element( child )
+                else:
+                    func = self.factory.create_function( child, self )
+                    self.functions_by_name[ func_name ] = func
 
-                elif child.name == "enum":
-                    enum = self.factory.create_item( "enum", child, self )
-                    self.enums_by_name[ enum.name ] = enum
-                elif child.name == "type":
-                    t = self.factory.create_item( "type", child, self )
-                    self.types_by_name[ "GL" + t.name ] = t
+                if func.offset >= self.next_offset:
+                    self.next_offset = func.offset + 1
 
 
-            child = child.next
+            elif child.tag == "enum":
+                enum = self.factory.create_enum( child, self, cat_name )
+                self.enums_by_name[ enum.name ] = enum
+            elif child.tag == "type":
+                t = self.factory.create_type( child, self, cat_name )
+                self.types_by_name[ "GL" + t.name ] = t
 
         return