1 | #!/usr/bin/env python |
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2 | #============================================================================ |
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3 | # This library is free software; you can redistribute it and/or |
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4 | # modify it under the terms of version 2.1 of the GNU Lesser General Public |
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5 | # License as published by the Free Software Foundation. |
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6 | # |
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7 | # This library is distributed in the hope that it will be useful, |
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8 | # but WITHOUT ANY WARRANTY; without even the implied warranty of |
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9 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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10 | # Lesser General Public License for more details. |
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11 | # |
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12 | # You should have received a copy of the GNU Lesser General Public |
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13 | # License along with this library; if not, write to the Free Software |
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14 | # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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15 | #============================================================================ |
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16 | # Copyright (C) 2004, 2005 Mike Wray <mike.wray@hp.com> |
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17 | #============================================================================ |
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18 | |
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19 | """ |
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20 | Input-driven parsing for s-expression (sxp) format. |
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21 | Create a parser: pin = Parser(); |
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22 | Then call pin.input(buf) with your input. |
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23 | Call pin.input_eof() when done. |
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24 | Use pin.read() to see if a value has been parsed, pin.get_val() |
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25 | to get a parsed value. You can call ready and get_val at any time - |
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26 | you don't have to wait until after calling input_eof. |
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27 | |
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28 | """ |
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29 | from __future__ import generators |
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30 | |
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31 | import sys |
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32 | import types |
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33 | import errno |
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34 | import string |
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35 | from StringIO import StringIO |
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36 | |
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37 | __all__ = [ |
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38 | "mime_type", |
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39 | "ParseError", |
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40 | "Parser", |
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41 | "atomp", |
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42 | "show", |
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43 | "show_xml", |
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44 | "elementp", |
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45 | "name", |
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46 | "attributes", |
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47 | "attribute", |
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48 | "children", |
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49 | "child", |
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50 | "child_at", |
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51 | "child0", |
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52 | "child1", |
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53 | "child2", |
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54 | "child3", |
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55 | "child4", |
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56 | "child_value", |
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57 | "has_id", |
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58 | "with_id", |
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59 | "child_with_id", |
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60 | "elements", |
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61 | "merge", |
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62 | "to_string", |
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63 | "from_string", |
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64 | "all_from_string", |
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65 | "parse", |
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66 | ] |
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67 | |
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68 | mime_type = "application/sxp" |
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69 | |
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70 | escapes = { |
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71 | 'a': '\a', |
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72 | 'b': '\b', |
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73 | 't': '\t', |
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74 | 'n': '\n', |
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75 | 'v': '\v', |
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76 | 'f': '\f', |
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77 | 'r': '\r', |
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78 | '\\': '\\', |
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79 | '\'': '\'', |
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80 | '\"': '\"'} |
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81 | |
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82 | k_list_open = "(" |
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83 | k_list_close = ")" |
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84 | k_attr_open = "@" |
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85 | k_eval = "!" |
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86 | |
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87 | escapes_rev = {} |
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88 | for k in escapes: |
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89 | escapes_rev[escapes[k]] = k |
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90 | |
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91 | class ParseError(StandardError): |
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92 | |
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93 | def __init__(self, parser, value): |
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94 | self.parser = parser |
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95 | self.value = value |
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96 | |
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97 | def __str__(self): |
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98 | return self.value |
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99 | |
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100 | class ParserState: |
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101 | |
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102 | def __init__(self, fn, parent=None): |
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103 | self.parent = parent |
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104 | self.buf = '' |
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105 | self.val = [] |
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106 | self.delim = None |
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107 | self.fn = fn |
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108 | |
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109 | def push(self, fn): |
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110 | return ParserState(fn, parent=self) |
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111 | |
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112 | class Parser: |
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113 | |
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114 | def __init__(self): |
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115 | self.error = sys.stderr |
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116 | self.reset() |
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117 | |
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118 | def reset(self): |
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119 | self.val = [] |
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120 | self.eof = 0 |
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121 | self.err = 0 |
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122 | self.line_no = 0 |
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123 | self.char_no = 0 |
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124 | self.state = None |
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125 | |
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126 | def push_state(self, fn): |
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127 | self.state = self.state.push(fn) |
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128 | |
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129 | def pop_state(self): |
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130 | val = self.state |
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131 | self.state = self.state.parent |
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132 | if self.state and self.state.fn == self.state_start: |
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133 | # Return to start state - produce the value. |
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134 | self.val += self.state.val |
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135 | self.state.val = [] |
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136 | return val |
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137 | |
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138 | def in_class(self, c, s): |
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139 | return s.find(c) >= 0 |
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140 | |
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141 | def in_space_class(self, c): |
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142 | return self.in_class(c, ' \t\n\v\f\r') |
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143 | |
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144 | def is_separator(self, c): |
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145 | return self.in_class(c, '{}()<>[]!;') |
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146 | |
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147 | def in_comment_class(self, c): |
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148 | return self.in_class(c, '#') |
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149 | |
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150 | def in_string_quote_class(self, c): |
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151 | return self.in_class(c, '"\'') |
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152 | |
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153 | def in_printable_class(self, c): |
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154 | return self.in_class(c, string.printable) |
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155 | |
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156 | def set_error_stream(self, error): |
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157 | self.error = error |
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158 | |
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159 | def has_error(self): |
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160 | return self.err > 0 |
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161 | |
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162 | def at_eof(self): |
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163 | return self.eof |
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164 | |
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165 | def input_eof(self): |
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166 | self.eof = 1 |
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167 | self.input_char(-1) |
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168 | |
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169 | def input(self, buf): |
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170 | if not buf or len(buf) == 0: |
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171 | self.input_eof() |
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172 | else: |
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173 | for c in buf: |
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174 | self.input_char(c) |
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175 | |
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176 | def input_char(self, c): |
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177 | if self.at_eof(): |
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178 | pass |
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179 | elif c == '\n': |
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180 | self.line_no += 1 |
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181 | self.char_no = 0 |
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182 | else: |
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183 | self.char_no += 1 |
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184 | |
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185 | if self.state is None: |
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186 | self.begin_start(None) |
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187 | self.state.fn(c) |
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188 | |
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189 | def ready(self): |
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190 | return len(self.val) > 0 |
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191 | |
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192 | def get_val(self): |
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193 | v = self.val[0] |
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194 | self.val = self.val[1:] |
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195 | return v |
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196 | |
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197 | def get_all(self): |
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198 | return self.val |
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199 | |
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200 | def begin_start(self, c): |
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201 | self.state = ParserState(self.state_start) |
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202 | |
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203 | def end_start(self): |
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204 | self.val += self.state.val |
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205 | self.pop_state() |
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206 | |
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207 | def state_start(self, c): |
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208 | if self.at_eof(): |
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209 | self.end_start() |
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210 | elif self.in_space_class(c): |
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211 | pass |
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212 | elif self.in_comment_class(c): |
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213 | self.begin_comment(c) |
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214 | elif c == k_list_open: |
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215 | self.begin_list(c) |
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216 | elif c == k_list_close: |
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217 | raise ParseError(self, "syntax error: "+c) |
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218 | elif self.in_string_quote_class(c): |
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219 | self.begin_string(c) |
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220 | elif self.in_printable_class(c): |
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221 | self.begin_atom(c) |
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222 | elif c == chr(4): |
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223 | # ctrl-D, EOT: end-of-text. |
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224 | self.input_eof() |
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225 | else: |
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226 | raise ParseError(self, "invalid character: code %d" % ord(c)) |
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227 | |
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228 | def begin_comment(self, c): |
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229 | self.push_state(self.state_comment) |
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230 | self.state.buf += c |
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231 | |
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232 | def end_comment(self): |
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233 | self.pop_state() |
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234 | |
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235 | def state_comment(self, c): |
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236 | if c == '\n' or self.at_eof(): |
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237 | self.end_comment() |
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238 | else: |
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239 | self.state.buf += c |
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240 | |
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241 | def begin_string(self, c): |
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242 | self.push_state(self.state_string) |
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243 | self.state.delim = c |
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244 | |
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245 | def end_string(self): |
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246 | val = self.state.buf |
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247 | self.state.parent.val.append(val) |
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248 | self.pop_state() |
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249 | |
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250 | def state_string(self, c): |
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251 | if self.at_eof(): |
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252 | raise ParseError(self, "unexpected EOF") |
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253 | elif c == self.state.delim: |
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254 | self.end_string() |
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255 | elif c == '\\': |
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256 | self.push_state(self.state_escape) |
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257 | else: |
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258 | self.state.buf += c |
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259 | |
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260 | def state_escape(self, c): |
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261 | if self.at_eof(): |
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262 | raise ParseError(self, "unexpected EOF") |
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263 | d = escapes.get(c) |
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264 | if d: |
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265 | self.state.parent.buf += d |
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266 | self.pop_state() |
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267 | elif c == 'x': |
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268 | self.state.fn = self.state_hex |
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269 | self.state.val = 0 |
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270 | elif c in string.octdigits: |
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271 | self.state.fn = self.state_octal |
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272 | self.state.val = 0 |
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273 | self.input_char(c) |
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274 | else: |
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275 | # ignore escape if it doesn't match anything we know |
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276 | self.state.parent.buf += '\\' |
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277 | self.pop_state() |
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278 | |
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279 | def state_octal(self, c): |
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280 | def octaldigit(c): |
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281 | self.state.val *= 8 |
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282 | self.state.val += ord(c) - ord('0') |
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283 | self.state.buf += c |
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284 | if self.state.val < 0 or self.state.val > 0xff: |
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285 | raise ParseError(self, "invalid octal escape: out of range " + self.state.buf) |
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286 | if len(self.state.buf) == 3: |
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287 | octaldone() |
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288 | |
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289 | def octaldone(): |
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290 | d = chr(self.state.val) |
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291 | self.state.parent.buf += d |
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292 | self.pop_state() |
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293 | |
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294 | if self.at_eof(): |
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295 | raise ParseError(self, "unexpected EOF") |
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296 | elif '0' <= c <= '7': |
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297 | octaldigit(c) |
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298 | elif len(self.state.buf): |
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299 | octaldone() |
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300 | self.input_char(c) |
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301 | |
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302 | def state_hex(self, c): |
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303 | def hexdone(): |
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304 | d = chr(self.state.val) |
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305 | self.state.parent.buf += d |
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306 | self.pop_state() |
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307 | |
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308 | def hexdigit(c, d): |
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309 | self.state.val *= 16 |
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310 | self.state.val += ord(c) - ord(d) |
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311 | self.state.buf += c |
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312 | if self.state.val < 0 or self.state.val > 0xff: |
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313 | raise ParseError(self, "invalid hex escape: out of range " + self.state.buf) |
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314 | if len(self.state.buf) == 2: |
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315 | hexdone() |
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316 | |
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317 | if self.at_eof(): |
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318 | raise ParseError(self, "unexpected EOF") |
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319 | elif '0' <= c <= '9': |
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320 | hexdigit(c, '0') |
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321 | elif 'A' <= c <= 'F': |
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322 | hexdigit(c, 'A') |
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323 | elif 'a' <= c <= 'f': |
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324 | hexdigit(c, 'a') |
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325 | elif len(buf): |
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326 | hexdone() |
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327 | self.input_char(c) |
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328 | |
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329 | def begin_atom(self, c): |
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330 | self.push_state(self.state_atom) |
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331 | self.state.buf = c |
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332 | |
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333 | def end_atom(self): |
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334 | val = self.state.buf |
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335 | self.state.parent.val.append(val) |
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336 | self.pop_state() |
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337 | |
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338 | def state_atom(self, c): |
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339 | if self.at_eof(): |
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340 | self.end_atom() |
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341 | elif (self.is_separator(c) or |
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342 | self.in_space_class(c) or |
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343 | self.in_comment_class(c)): |
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344 | self.end_atom() |
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345 | self.input_char(c) |
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346 | else: |
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347 | self.state.buf += c |
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348 | |
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349 | def begin_list(self, c): |
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350 | self.push_state(self.state_list) |
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351 | |
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352 | def end_list(self): |
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353 | val = self.state.val |
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354 | self.state.parent.val.append(val) |
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355 | self.pop_state() |
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356 | |
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357 | def state_list(self, c): |
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358 | if self.at_eof(): |
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359 | raise ParseError(self, "unexpected EOF") |
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360 | elif c == k_list_close: |
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361 | self.end_list() |
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362 | else: |
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363 | self.state_start(c) |
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364 | |
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365 | def atomp(sxpr): |
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366 | """Check if an sxpr is an atom. |
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367 | """ |
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368 | if sxpr.isalnum() or sxpr == '@': |
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369 | return 1 |
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370 | for c in sxpr: |
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371 | if c in string.whitespace: return 0 |
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372 | if c in '"\'\\(){}[]<>$#&%^': return 0 |
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373 | if c in string.ascii_letters: continue |
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374 | if c in string.digits: continue |
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375 | if c in '.-_:/~': continue |
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376 | return 0 |
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377 | return 1 |
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378 | |
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379 | def show(sxpr, out=sys.stdout): |
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380 | """Print an sxpr in bracketed (lisp-style) syntax. |
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381 | """ |
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382 | if isinstance(sxpr, (types.ListType, types.TupleType)): |
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383 | out.write(k_list_open) |
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384 | i = 0 |
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385 | for x in sxpr: |
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386 | if i: out.write(' ') |
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387 | show(x, out) |
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388 | i += 1 |
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389 | out.write(k_list_close) |
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390 | elif isinstance(sxpr, (types.IntType, types.FloatType)): |
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391 | out.write(str(sxpr)) |
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392 | elif isinstance(sxpr, types.StringType) and atomp(sxpr): |
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393 | out.write(sxpr) |
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394 | else: |
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395 | out.write(repr(str(sxpr))) |
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396 | |
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397 | def show_xml(sxpr, out=sys.stdout): |
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398 | """Print an sxpr in XML syntax. |
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399 | """ |
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400 | if isinstance(sxpr, (types.ListType, types.TupleType)): |
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401 | element = name(sxpr) |
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402 | out.write('<%s' % element) |
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403 | for attr in attributes(sxpr): |
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404 | out.write(' %s=%s' % (attr[0], attr[1])) |
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405 | out.write('>') |
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406 | i = 0 |
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407 | for x in children(sxpr): |
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408 | if i: out.write(' ') |
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409 | show_xml(x, out) |
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410 | i += 1 |
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411 | out.write('</%s>' % element) |
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412 | elif isinstance(sxpr, types.StringType) and atomp(sxpr): |
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413 | out.write(sxpr) |
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414 | else: |
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415 | out.write(str(sxpr)) |
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416 | |
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417 | def elementp(sxpr, elt=None): |
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418 | """Check if an sxpr is an element of the given type. |
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419 | |
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420 | sxpr sxpr |
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421 | elt element type |
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422 | """ |
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423 | return (isinstance(sxpr, (types.ListType, types.TupleType)) |
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424 | and len(sxpr) |
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425 | and (None == elt or sxpr[0] == elt)) |
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426 | |
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427 | def name(sxpr): |
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428 | """Get the element name of an sxpr. |
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429 | If the sxpr is not an element (i.e. it's an atomic value) its name |
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430 | is None. |
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431 | |
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432 | sxpr |
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433 | |
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434 | returns name (None if not an element). |
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435 | """ |
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436 | val = None |
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437 | if isinstance(sxpr, types.StringType): |
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438 | val = sxpr |
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439 | elif isinstance(sxpr, (types.ListType, types.TupleType)) and len(sxpr): |
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440 | val = sxpr[0] |
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441 | return val |
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442 | |
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443 | def attributes(sxpr): |
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444 | """Get the attribute list of an sxpr. |
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445 | |
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446 | sxpr |
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447 | |
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448 | returns attribute list |
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449 | """ |
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450 | val = [] |
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451 | if isinstance(sxpr, (types.ListType, types.TupleType)) and len(sxpr) > 1: |
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452 | attr = sxpr[1] |
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453 | if elementp(attr, k_attr_open): |
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454 | val = attr[1:] |
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455 | return val |
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456 | |
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457 | def attribute(sxpr, key, val=None): |
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458 | """Get an attribute of an sxpr. |
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459 | |
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460 | sxpr sxpr |
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461 | key attribute key |
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462 | val default value (default None) |
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463 | |
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464 | returns attribute value |
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465 | """ |
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466 | for x in attributes(sxpr): |
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467 | if x[0] == key: |
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468 | val = x[1] |
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469 | break |
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470 | return val |
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471 | |
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472 | def children(sxpr, elt=None): |
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473 | """Get children of an sxpr. |
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474 | |
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475 | sxpr sxpr |
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476 | elt optional element type to filter by |
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477 | |
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478 | returns children (filtered by elt if specified) |
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479 | """ |
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480 | val = [] |
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481 | if isinstance(sxpr, (types.ListType, types.TupleType)) and len(sxpr) > 1: |
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482 | i = 1 |
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483 | x = sxpr[i] |
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484 | if elementp(x, k_attr_open): |
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485 | i += 1 |
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486 | val = sxpr[i : ] |
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487 | if elt: |
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488 | def iselt(x): |
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489 | return elementp(x, elt) |
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490 | val = filter(iselt, val) |
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491 | return val |
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492 | |
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493 | def child(sxpr, elt, val=None): |
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494 | """Get the first child of the given element type. |
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495 | |
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496 | sxpr sxpr |
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497 | elt element type |
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498 | val default value |
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499 | """ |
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500 | for x in children(sxpr): |
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501 | if elementp(x, elt): |
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502 | val = x |
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503 | break |
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504 | return val |
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505 | |
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506 | def child_at(sxpr, index, val=None): |
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507 | """Get the child at the given index (zero-based). |
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508 | |
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509 | sxpr sxpr |
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510 | index index |
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511 | val default value |
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512 | """ |
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513 | kids = children(sxpr) |
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514 | if len(kids) > index: |
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515 | val = kids[index] |
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516 | return val |
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517 | |
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518 | def child0(sxpr, val=None): |
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519 | """Get the zeroth child. |
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520 | """ |
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521 | return child_at(sxpr, 0, val) |
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522 | |
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523 | def child1(sxpr, val=None): |
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524 | """Get the first child. |
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525 | """ |
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526 | return child_at(sxpr, 1, val) |
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527 | |
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528 | def child2(sxpr, val=None): |
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529 | """Get the second child. |
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530 | """ |
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531 | return child_at(sxpr, 2, val) |
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532 | |
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533 | def child3(sxpr, val=None): |
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534 | """Get the third child. |
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535 | """ |
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536 | return child_at(sxpr, 3, val) |
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537 | |
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538 | def child4(sxpr, val=None): |
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539 | """Get the fourth child. |
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540 | """ |
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541 | return child_at(sxpr, 4, val) |
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542 | |
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543 | def child_value(sxpr, elt, val=None): |
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544 | """Get the value of the first child of the given element type. |
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545 | Assumes the child has an atomic value. |
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546 | |
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547 | sxpr sxpr |
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548 | elt element type |
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549 | val default value |
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550 | """ |
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551 | kid = child(sxpr, elt) |
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552 | if kid: |
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553 | val = child_at(kid, 0, val) |
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554 | return val |
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555 | |
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556 | def has_id(sxpr, id): |
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557 | """Test if an s-expression has a given id. |
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558 | """ |
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559 | return attribute(sxpr, 'id') == id |
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560 | |
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561 | def with_id(sxpr, id, val=None): |
---|
562 | """Find the first s-expression with a given id, at any depth. |
---|
563 | |
---|
564 | sxpr s-exp or list |
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565 | id id |
---|
566 | val value if not found (default None) |
---|
567 | |
---|
568 | return s-exp or val |
---|
569 | """ |
---|
570 | if isinstance(sxpr, (types.ListType, types.TupleType)): |
---|
571 | for n in sxpr: |
---|
572 | if has_id(n, id): |
---|
573 | val = n |
---|
574 | break |
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575 | v = with_id(n, id) |
---|
576 | if v is None: continue |
---|
577 | val = v |
---|
578 | break |
---|
579 | return val |
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580 | |
---|
581 | def child_with_id(sxpr, id, val=None): |
---|
582 | """Find the first child with a given id. |
---|
583 | |
---|
584 | sxpr s-exp or list |
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585 | id id |
---|
586 | val value if not found (default None) |
---|
587 | |
---|
588 | return s-exp or val |
---|
589 | """ |
---|
590 | if isinstance(sxpr, (types.ListType, types.TupleType)): |
---|
591 | for n in sxpr: |
---|
592 | if has_id(n, id): |
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593 | val = n |
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594 | break |
---|
595 | return val |
---|
596 | |
---|
597 | def elements(sxpr, ctxt=None): |
---|
598 | """Generate elements (at any depth). |
---|
599 | Visit elements in pre-order. |
---|
600 | Values generated are (node, context) |
---|
601 | The context is None if there is no parent, otherwise |
---|
602 | (index, parent, context) where index is the node's index w.r.t its parent, |
---|
603 | and context is the parent's context. |
---|
604 | |
---|
605 | sxpr s-exp |
---|
606 | |
---|
607 | returns generator |
---|
608 | """ |
---|
609 | yield (sxpr, ctxt) |
---|
610 | i = 0 |
---|
611 | for n in children(sxpr): |
---|
612 | if isinstance(n, (types.ListType, types.TupleType)): |
---|
613 | # Calling elements() recursively does not generate recursively, |
---|
614 | # it just returns a generator object. So we must iterate over it. |
---|
615 | for v in elements(n, (i, sxpr, ctxt)): |
---|
616 | yield v |
---|
617 | i += 1 |
---|
618 | |
---|
619 | def merge(s1, s2): |
---|
620 | """Merge sxprs s1 and s2. |
---|
621 | Returns an sxpr containing all the fields from s1 and s2, with |
---|
622 | entries in s1 overriding s2. Recursively merges fields. |
---|
623 | |
---|
624 | @param s1 sxpr |
---|
625 | @param s2 sxpr |
---|
626 | @return merged sxpr |
---|
627 | """ |
---|
628 | if s1 is None: |
---|
629 | val = s2 |
---|
630 | elif s2 is None: |
---|
631 | val = s1 |
---|
632 | elif elementp(s1): |
---|
633 | name1 = name(s1) |
---|
634 | (m1, v1) = child_map(s1) |
---|
635 | (m2, v2) = child_map(s2) |
---|
636 | val = [name1] |
---|
637 | for (k1, f1) in m1.items(): |
---|
638 | merge_list(val, f1, m2.get(k1, [])) |
---|
639 | for (k2, f2) in m2.items(): |
---|
640 | if k2 in m1: continue |
---|
641 | val.extend(f2) |
---|
642 | val.extend(v1) |
---|
643 | else: |
---|
644 | val = s1 |
---|
645 | return val |
---|
646 | |
---|
647 | def merge_list(sxpr, l1, l2): |
---|
648 | """Merge element lists l1 and l2 into sxpr. |
---|
649 | The lists l1 and l2 are all element with the same name. |
---|
650 | Values from l1 are merged with values in l2 and stored in sxpr. |
---|
651 | If one list is longer than the other the excess values are used |
---|
652 | as they are. |
---|
653 | |
---|
654 | @param sxpr to merge into |
---|
655 | @param l1 sxpr list |
---|
656 | @param l2 sxpr list |
---|
657 | @return modified sxpr |
---|
658 | """ |
---|
659 | n1 = len(l1) |
---|
660 | n2 = len(l2) |
---|
661 | nmin = min(n1, n2) |
---|
662 | for i in range(0, nmin): |
---|
663 | sxpr.append(merge(l1[i], l2[i])) |
---|
664 | for i in range(nmin, n1): |
---|
665 | sxpr.append(l1[i]) |
---|
666 | for i in range(nmin, n2): |
---|
667 | sxpr.append(l2[i]) |
---|
668 | return sxpr |
---|
669 | |
---|
670 | def child_map(sxpr): |
---|
671 | """Get a dict of the elements in sxpr and a list of its values. |
---|
672 | The dict maps element name to the list of elements with that name, |
---|
673 | and the list is the non-element children. |
---|
674 | |
---|
675 | @param sxpr |
---|
676 | @return (dict, list) |
---|
677 | """ |
---|
678 | m = {} |
---|
679 | v = [] |
---|
680 | for x in children(sxpr): |
---|
681 | if elementp(x): |
---|
682 | n = name(x) |
---|
683 | l = m.get(n, []) |
---|
684 | l.append(x) |
---|
685 | m[n] = l |
---|
686 | else: |
---|
687 | v.append(x) |
---|
688 | return (m, v) |
---|
689 | |
---|
690 | def to_string(sxpr): |
---|
691 | """Convert an sxpr to a string. |
---|
692 | |
---|
693 | sxpr sxpr |
---|
694 | returns string |
---|
695 | """ |
---|
696 | io = StringIO() |
---|
697 | show(sxpr, io) |
---|
698 | io.seek(0) |
---|
699 | val = io.getvalue() |
---|
700 | io.close() |
---|
701 | return val |
---|
702 | |
---|
703 | def from_string(s): |
---|
704 | """Create an sxpr by parsing a string. |
---|
705 | |
---|
706 | s string |
---|
707 | returns sxpr |
---|
708 | """ |
---|
709 | if s == '': |
---|
710 | return [] |
---|
711 | |
---|
712 | io = StringIO(s) |
---|
713 | vals = parse(io) |
---|
714 | if vals is []: |
---|
715 | return None |
---|
716 | else: |
---|
717 | return vals[0] |
---|
718 | |
---|
719 | |
---|
720 | def all_from_string(s): |
---|
721 | """Create an sxpr list by parsing a string. |
---|
722 | |
---|
723 | s string |
---|
724 | returns sxpr list |
---|
725 | """ |
---|
726 | io = StringIO(s) |
---|
727 | vals = parse(io) |
---|
728 | return vals |
---|
729 | |
---|
730 | def parse(io): |
---|
731 | """Completely parse all input from 'io'. |
---|
732 | |
---|
733 | io input file object |
---|
734 | returns list of values, None if incomplete |
---|
735 | raises ParseError on parse error |
---|
736 | """ |
---|
737 | pin = Parser() |
---|
738 | while 1: |
---|
739 | buf = io.readline() |
---|
740 | pin.input(buf) |
---|
741 | if len(buf) == 0: |
---|
742 | break |
---|
743 | if pin.ready(): |
---|
744 | val = pin.get_all() |
---|
745 | else: |
---|
746 | val = None |
---|
747 | return val |
---|
748 | |
---|
749 | |
---|
750 | if __name__ == '__main__': |
---|
751 | print ">main" |
---|
752 | pin = Parser() |
---|
753 | while 1: |
---|
754 | buf = sys.stdin.read(1024) |
---|
755 | #buf = sys.stdin.readline() |
---|
756 | pin.input(buf) |
---|
757 | while pin.ready(): |
---|
758 | val = pin.get_val() |
---|
759 | print |
---|
760 | print '****** val=', val |
---|
761 | if len(buf) == 0: |
---|
762 | break |
---|
763 | |
---|