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author | xiubuzhe <xiubuzhe@sina.com> | 2023-10-08 20:59:00 +0800 |
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committer | xiubuzhe <xiubuzhe@sina.com> | 2023-10-08 20:59:00 +0800 |
commit | 1dac2263372df2b85db5d029a45721fa158a5c9d (patch) | |
tree | 0365f9c57df04178a726d7584ca6a6b955a7ce6a /lib/pycparser/_ast_gen.py | |
parent | b494be364bb39e1de128ada7dc576a729d99907e (diff) | |
download | sunhpc-1dac2263372df2b85db5d029a45721fa158a5c9d.tar.gz sunhpc-1dac2263372df2b85db5d029a45721fa158a5c9d.tar.bz2 sunhpc-1dac2263372df2b85db5d029a45721fa158a5c9d.zip |
first add files
Diffstat (limited to 'lib/pycparser/_ast_gen.py')
-rw-r--r-- | lib/pycparser/_ast_gen.py | 336 |
1 files changed, 336 insertions, 0 deletions
diff --git a/lib/pycparser/_ast_gen.py b/lib/pycparser/_ast_gen.py new file mode 100644 index 0000000..0f7d330 --- /dev/null +++ b/lib/pycparser/_ast_gen.py @@ -0,0 +1,336 @@ +#----------------------------------------------------------------- +# _ast_gen.py +# +# Generates the AST Node classes from a specification given in +# a configuration file +# +# The design of this module was inspired by astgen.py from the +# Python 2.5 code-base. +# +# Eli Bendersky [https://eli.thegreenplace.net/] +# License: BSD +#----------------------------------------------------------------- +from string import Template + + +class ASTCodeGenerator(object): + def __init__(self, cfg_filename='_c_ast.cfg'): + """ Initialize the code generator from a configuration + file. + """ + self.cfg_filename = cfg_filename + self.node_cfg = [NodeCfg(name, contents) + for (name, contents) in self.parse_cfgfile(cfg_filename)] + + def generate(self, file=None): + """ Generates the code into file, an open file buffer. + """ + src = Template(_PROLOGUE_COMMENT).substitute( + cfg_filename=self.cfg_filename) + + src += _PROLOGUE_CODE + for node_cfg in self.node_cfg: + src += node_cfg.generate_source() + '\n\n' + + file.write(src) + + def parse_cfgfile(self, filename): + """ Parse the configuration file and yield pairs of + (name, contents) for each node. + """ + with open(filename, "r") as f: + for line in f: + line = line.strip() + if not line or line.startswith('#'): + continue + colon_i = line.find(':') + lbracket_i = line.find('[') + rbracket_i = line.find(']') + if colon_i < 1 or lbracket_i <= colon_i or rbracket_i <= lbracket_i: + raise RuntimeError("Invalid line in %s:\n%s\n" % (filename, line)) + + name = line[:colon_i] + val = line[lbracket_i + 1:rbracket_i] + vallist = [v.strip() for v in val.split(',')] if val else [] + yield name, vallist + + +class NodeCfg(object): + """ Node configuration. + + name: node name + contents: a list of contents - attributes and child nodes + See comment at the top of the configuration file for details. + """ + + def __init__(self, name, contents): + self.name = name + self.all_entries = [] + self.attr = [] + self.child = [] + self.seq_child = [] + + for entry in contents: + clean_entry = entry.rstrip('*') + self.all_entries.append(clean_entry) + + if entry.endswith('**'): + self.seq_child.append(clean_entry) + elif entry.endswith('*'): + self.child.append(clean_entry) + else: + self.attr.append(entry) + + def generate_source(self): + src = self._gen_init() + src += '\n' + self._gen_children() + src += '\n' + self._gen_iter() + src += '\n' + self._gen_attr_names() + return src + + def _gen_init(self): + src = "class %s(Node):\n" % self.name + + if self.all_entries: + args = ', '.join(self.all_entries) + slots = ', '.join("'{0}'".format(e) for e in self.all_entries) + slots += ", 'coord', '__weakref__'" + arglist = '(self, %s, coord=None)' % args + else: + slots = "'coord', '__weakref__'" + arglist = '(self, coord=None)' + + src += " __slots__ = (%s)\n" % slots + src += " def __init__%s:\n" % arglist + + for name in self.all_entries + ['coord']: + src += " self.%s = %s\n" % (name, name) + + return src + + def _gen_children(self): + src = ' def children(self):\n' + + if self.all_entries: + src += ' nodelist = []\n' + + for child in self.child: + src += ( + ' if self.%(child)s is not None:' + + ' nodelist.append(("%(child)s", self.%(child)s))\n') % ( + dict(child=child)) + + for seq_child in self.seq_child: + src += ( + ' for i, child in enumerate(self.%(child)s or []):\n' + ' nodelist.append(("%(child)s[%%d]" %% i, child))\n') % ( + dict(child=seq_child)) + + src += ' return tuple(nodelist)\n' + else: + src += ' return ()\n' + + return src + + def _gen_iter(self): + src = ' def __iter__(self):\n' + + if self.all_entries: + for child in self.child: + src += ( + ' if self.%(child)s is not None:\n' + + ' yield self.%(child)s\n') % (dict(child=child)) + + for seq_child in self.seq_child: + src += ( + ' for child in (self.%(child)s or []):\n' + ' yield child\n') % (dict(child=seq_child)) + + if not (self.child or self.seq_child): + # Empty generator + src += ( + ' return\n' + + ' yield\n') + else: + # Empty generator + src += ( + ' return\n' + + ' yield\n') + + return src + + def _gen_attr_names(self): + src = " attr_names = (" + ''.join("%r, " % nm for nm in self.attr) + ')' + return src + + +_PROLOGUE_COMMENT = \ +r'''#----------------------------------------------------------------- +# ** ATTENTION ** +# This code was automatically generated from the file: +# $cfg_filename +# +# Do not modify it directly. Modify the configuration file and +# run the generator again. +# ** ** *** ** ** +# +# pycparser: c_ast.py +# +# AST Node classes. +# +# Eli Bendersky [https://eli.thegreenplace.net/] +# License: BSD +#----------------------------------------------------------------- + +''' + +_PROLOGUE_CODE = r''' +import sys + +def _repr(obj): + """ + Get the representation of an object, with dedicated pprint-like format for lists. + """ + if isinstance(obj, list): + return '[' + (',\n '.join((_repr(e).replace('\n', '\n ') for e in obj))) + '\n]' + else: + return repr(obj) + +class Node(object): + __slots__ = () + """ Abstract base class for AST nodes. + """ + def __repr__(self): + """ Generates a python representation of the current node + """ + result = self.__class__.__name__ + '(' + + indent = '' + separator = '' + for name in self.__slots__[:-2]: + result += separator + result += indent + result += name + '=' + (_repr(getattr(self, name)).replace('\n', '\n ' + (' ' * (len(name) + len(self.__class__.__name__))))) + + separator = ',' + indent = '\n ' + (' ' * len(self.__class__.__name__)) + + result += indent + ')' + + return result + + def children(self): + """ A sequence of all children that are Nodes + """ + pass + + def show(self, buf=sys.stdout, offset=0, attrnames=False, nodenames=False, showcoord=False, _my_node_name=None): + """ Pretty print the Node and all its attributes and + children (recursively) to a buffer. + + buf: + Open IO buffer into which the Node is printed. + + offset: + Initial offset (amount of leading spaces) + + attrnames: + True if you want to see the attribute names in + name=value pairs. False to only see the values. + + nodenames: + True if you want to see the actual node names + within their parents. + + showcoord: + Do you want the coordinates of each Node to be + displayed. + """ + lead = ' ' * offset + if nodenames and _my_node_name is not None: + buf.write(lead + self.__class__.__name__+ ' <' + _my_node_name + '>: ') + else: + buf.write(lead + self.__class__.__name__+ ': ') + + if self.attr_names: + if attrnames: + nvlist = [(n, getattr(self,n)) for n in self.attr_names] + attrstr = ', '.join('%s=%s' % nv for nv in nvlist) + else: + vlist = [getattr(self, n) for n in self.attr_names] + attrstr = ', '.join('%s' % v for v in vlist) + buf.write(attrstr) + + if showcoord: + buf.write(' (at %s)' % self.coord) + buf.write('\n') + + for (child_name, child) in self.children(): + child.show( + buf, + offset=offset + 2, + attrnames=attrnames, + nodenames=nodenames, + showcoord=showcoord, + _my_node_name=child_name) + + +class NodeVisitor(object): + """ A base NodeVisitor class for visiting c_ast nodes. + Subclass it and define your own visit_XXX methods, where + XXX is the class name you want to visit with these + methods. + + For example: + + class ConstantVisitor(NodeVisitor): + def __init__(self): + self.values = [] + + def visit_Constant(self, node): + self.values.append(node.value) + + Creates a list of values of all the constant nodes + encountered below the given node. To use it: + + cv = ConstantVisitor() + cv.visit(node) + + Notes: + + * generic_visit() will be called for AST nodes for which + no visit_XXX method was defined. + * The children of nodes for which a visit_XXX was + defined will not be visited - if you need this, call + generic_visit() on the node. + You can use: + NodeVisitor.generic_visit(self, node) + * Modeled after Python's own AST visiting facilities + (the ast module of Python 3.0) + """ + + _method_cache = None + + def visit(self, node): + """ Visit a node. + """ + + if self._method_cache is None: + self._method_cache = {} + + visitor = self._method_cache.get(node.__class__.__name__, None) + if visitor is None: + method = 'visit_' + node.__class__.__name__ + visitor = getattr(self, method, self.generic_visit) + self._method_cache[node.__class__.__name__] = visitor + + return visitor(node) + + def generic_visit(self, node): + """ Called if no explicit visitor function exists for a + node. Implements preorder visiting of the node. + """ + for c in node: + self.visit(c) + +''' |