00001 /******************************************************************************* 00002 00003 @file TokenStack.d 00004 00005 Copyright (C) 2004 Kris Bell 00006 00007 This software is provided 'as-is', without any express or implied 00008 warranty. In no event will the authors be held liable for damages 00009 of any kind arising from the use of this software. 00010 00011 Permission is hereby granted to anyone to use this software for any 00012 purpose, including commercial applications, and to alter it and/or 00013 redistribute it freely, subject to the following restrictions: 00014 00015 1. The origin of this software must not be misrepresented; you must 00016 not claim that you wrote the original software. If you use this 00017 software in a product, an acknowledgment within documentation of 00018 said product would be appreciated but is not required. 00019 00020 2. Altered source versions must be plainly marked as such, and must 00021 not be misrepresented as being the original software. 00022 00023 3. This notice may not be removed or altered from any distribution 00024 of the source. 00025 00026 00027 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 00028 00029 00030 @version Initial version, April 2004 00031 @author Kris, John Reimer 00032 00033 00034 *******************************************************************************/ 00035 00036 module mango.http.utils.TokenStack; 00037 00038 private import mango.io.Token, 00039 mango.io.Exception; 00040 00041 /****************************************************************************** 00042 00043 linux doesn't appear to have a memicmp() ... JJR notes that the 00044 strncasecmp() is available instead. 00045 00046 ******************************************************************************/ 00047 00048 version (Win32) 00049 { 00050 extern (C) int memicmp (char *, char *, uint); 00051 } 00052 00053 version (linux) 00054 { 00055 extern (C) int strncasecmp (char *, char*, uint); 00056 } 00057 00058 /****************************************************************************** 00059 00060 A stack of Tokens, used for capturing http headers. The tokens 00061 themselves are typically mapped onto the content of a Buffer, 00062 or some other external content, so there's minimal allocation 00063 involved (typically zero). 00064 00065 ******************************************************************************/ 00066 00067 class TokenStack 00068 { 00069 private int depth; 00070 private Token[] tokens; 00071 00072 private static const int MaxTokenStackSize = 256; 00073 00074 /********************************************************************** 00075 00076 Construct a TokenStack with the specified initial size. 00077 The stack will later be resized as necessary. 00078 00079 **********************************************************************/ 00080 00081 this (int size = 10) 00082 { 00083 tokens = new Token[0]; 00084 resize (tokens, size); 00085 } 00086 00087 /********************************************************************** 00088 00089 Clone this stack of tokens 00090 00091 **********************************************************************/ 00092 00093 TokenStack clone () 00094 { 00095 // setup a new tokenstack of the same depth 00096 TokenStack clone = new TokenStack(depth); 00097 00098 clone.depth = depth; 00099 00100 // duplicate the content of each original token 00101 for (int i=0; i < depth; ++i) 00102 clone.tokens[i].set (tokens[i].toString().dup); 00103 00104 return clone; 00105 } 00106 00107 /********************************************************************** 00108 00109 Iterate over all tokens in stack 00110 00111 **********************************************************************/ 00112 00113 int opApply (int delegate(inout Token) dg) 00114 { 00115 int result = 0; 00116 00117 for (int i=0; i < depth; ++i) 00118 if ((result = dg (tokens[i])) != 0) 00119 break; 00120 return result; 00121 } 00122 00123 /********************************************************************** 00124 00125 Pop the stack all the way back to zero 00126 00127 **********************************************************************/ 00128 00129 final void reset () 00130 { 00131 depth = 0; 00132 } 00133 00134 /********************************************************************** 00135 00136 Scan the tokens looking for the first one with a matching 00137 name. Returns the matching Token, or null if there is no 00138 such match. 00139 00140 **********************************************************************/ 00141 00142 final Token findToken (char[] match) 00143 { 00144 Token tok; 00145 00146 for (int i=0; i < depth; ++i) 00147 { 00148 tok = tokens[i]; 00149 if (isMatch (tok, match)) 00150 return tok; 00151 } 00152 return null; 00153 } 00154 00155 /********************************************************************** 00156 00157 Return the current stack depth 00158 00159 **********************************************************************/ 00160 00161 final int size () 00162 { 00163 return depth; 00164 } 00165 00166 /********************************************************************** 00167 00168 Push a new token onto the stack, and set it content to 00169 that provided. Returns the new Token. 00170 00171 **********************************************************************/ 00172 00173 final Token push (char[] content) 00174 { 00175 return push().set (content); 00176 } 00177 00178 /********************************************************************** 00179 00180 Push a new token onto the stack, and set it content to 00181 be that of the specified token. Returns the new Token. 00182 00183 **********************************************************************/ 00184 00185 final Token push (Token token) 00186 { 00187 return push (token.toString()); 00188 } 00189 00190 /********************************************************************** 00191 00192 Push a new token onto the stack, and return it. 00193 00194 **********************************************************************/ 00195 00196 final Token push () 00197 { 00198 if (depth == tokens.length) 00199 resize (tokens, depth * 2); 00200 return tokens[depth++]; 00201 } 00202 00203 /********************************************************************** 00204 00205 Pop the stack by one. 00206 00207 **********************************************************************/ 00208 00209 final void pop () 00210 { 00211 if (depth) 00212 --depth; 00213 else 00214 throw new IOException ("illegal attempt to pop Token stack"); 00215 } 00216 00217 /********************************************************************** 00218 00219 See if the given token matches the specified text. The 00220 two must match the minimal extent exactly. 00221 00222 **********************************************************************/ 00223 00224 final static bool isMatch (Token token, char[] match) 00225 { 00226 char[] target = token.toString(); 00227 00228 int length = target.length; 00229 if (length > match.length) 00230 length = match.length; 00231 00232 version (Win32) 00233 return memicmp (target, match, length) == 0; 00234 version (linux) 00235 return strncasecmp (cast(char *)target, cast(char *)match, length) == 0; 00236 } 00237 00238 /********************************************************************** 00239 00240 Resize this stack by extending the array. 00241 00242 **********************************************************************/ 00243 00244 final static void resize (inout Token[] tokens, int size) 00245 { 00246 int i = tokens.length; 00247 00248 // this should *never* realistically happen 00249 if (size > MaxTokenStackSize) 00250 throw new IOException ("Token stack exceeds maximum depth"); 00251 00252 for (tokens.length=size; i < tokens.length; ++i) 00253 tokens[i] = new Token(); 00254 } 00255 }