1 # Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 # Use of this source code is governed by a BSD-style license that can be 3 # found in the LICENSE file. 4 5 import json 6 import struct_generator 7 8 def _JSONToCString16(json_string_literal): 9 """Converts a JSON string literal to a C++ UTF-16 string literal. This is 10 done by converting \\u#### to \\x####. 11 """ 12 c_string_literal = json_string_literal 13 escape_index = c_string_literal.find('\\') 14 while escape_index > 0: 15 if c_string_literal[escape_index + 1] == 'u': 16 # We close the C string literal after the 4 hex digits and reopen it right 17 # after, otherwise the Windows compiler will sometimes try to get more 18 # than 4 characters in the hex string. 19 c_string_literal = (c_string_literal[0:escape_index + 1] + 'x' + 20 c_string_literal[escape_index + 2:escape_index + 6] + '" L"' + 21 c_string_literal[escape_index + 6:]) 22 escape_index = c_string_literal.find('\\', escape_index + 6) 23 return c_string_literal 24 25 def _GenerateString(content, lines): 26 """Generates an UTF-8 string to be included in a static structure initializer. 27 If content is not specified, uses NULL. 28 """ 29 if content is None: 30 lines.append(' NULL,') 31 else: 32 # json.dumps quotes the string and escape characters as required. 33 lines.append(' %s,' % json.dumps(content)) 34 35 def _GenerateString16(content, lines): 36 """Generates an UTF-16 string to be included in a static structure 37 initializer. If content is not specified, uses NULL. 38 """ 39 if content is None: 40 lines.append(' NULL,') 41 else: 42 # json.dumps quotes the string and escape characters as required. 43 lines.append(' L%s,' % _JSONToCString16(json.dumps(content))) 44 45 def _GenerateArray(element_name, field_info, content, lines): 46 """Generates an array to be included in a static structure initializer. If 47 content is not specified, uses NULL. The array is assigned to a temporary 48 variable which is initialized before the structure. 49 """ 50 if content is None: 51 lines.append(' NULL,') 52 lines.append(' 0,') # Size of the array. 53 return 54 55 # Create a new array variable and use it in the structure initializer. 56 # This prohibits nested arrays. Add a clash detection and renaming mechanism 57 # to solve the problem. 58 var = 'array_%s_%s' % (element_name, field_info['field']); 59 lines.append(' %s,' % var) 60 lines.append(' %s,' % len(content)) # Size of the array. 61 # Generate the array content. 62 array_lines = [] 63 field_info['contents']['field'] = var; 64 array_lines.append(struct_generator.GenerateField( 65 field_info['contents']) + '[] = {') 66 for subcontent in content: 67 GenerateFieldContent(element_name, field_info['contents'], subcontent, 68 array_lines) 69 array_lines.append('};') 70 # Prepend the generated array so it is initialized before the structure. 71 lines.reverse() 72 array_lines.reverse() 73 lines.extend(array_lines) 74 lines.reverse() 75 76 def GenerateFieldContent(element_name, field_info, content, lines): 77 """Generate the content of a field to be included in the static structure 78 initializer. If the field's content is not specified, uses the default value 79 if one exists. 80 """ 81 if content is None: 82 content = field_info.get('default', None) 83 type = field_info['type'] 84 if type == 'int' or type == 'enum': 85 lines.append(' %s,' % content) 86 elif type == 'string': 87 _GenerateString(content, lines) 88 elif type == 'string16': 89 _GenerateString16(content, lines) 90 elif type == 'array': 91 _GenerateArray(element_name, field_info, content, lines) 92 else: 93 raise RuntimeError('Unknown field type "%s"' % type) 94 95 def GenerateElement(type_name, schema, element_name, element): 96 """Generate the static structure initializer for one element. 97 """ 98 lines = []; 99 lines.append('const %s %s = {' % (type_name, element_name)); 100 for field_info in schema: 101 content = element.get(field_info['field'], None) 102 if (content == None and not field_info.get('optional', False)): 103 raise RuntimeError('Mandatory field "%s" omitted in element "%s".' % 104 (field_info['field'], element_name)) 105 GenerateFieldContent(element_name, field_info, content, lines) 106 lines.append('};') 107 return '\n'.join(lines) 108 109 def GenerateElements(type_name, schema, description): 110 """Generate the static structure initializer for all the elements in the 111 description['elements'] dictionary, as well as for any variables in 112 description['int_variables']. 113 """ 114 result = []; 115 for var_name, value in description.get('int_variables', {}).items(): 116 result.append('const int %s = %s;' % (var_name, value)) 117 result.append('') 118 119 for element_name, element in description.get('elements', {}).items(): 120 result.append(GenerateElement(type_name, schema, element_name, element)) 121 result.append('') 122 return '\n'.join(result) 123
