xpcom/io/nsEscape.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 1998
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either of the GNU General Public License Version 2 or later (the "GPL"),
  26  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  27  * in which case the provisions of the GPL or the LGPL are applicable instead
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  36  * ***** END LICENSE BLOCK ***** */
  37
  38 /*      First checked in on 98/12/03 by John R. McMullen, derived from net.h/mkparse.c. */
  39
  40 #ifndef _ESCAPE_H_
  41 #define _ESCAPE_H_
  42
  43 #include "prtypes.h"
  44 #include "nscore.h"
  45 #include "nsError.h"
  46 #include "nsString.h"
  47
  48 /**
  49  * Valid mask values for nsEscape
  50  * Note: these values are copied in nsINetUtil.idl. Any changes should be kept
  51  * in sync.
  52  */
  53 typedef enum {
  54         url_All       = 0         /**< %-escape every byte uncondtionally */
  55 ,       url_XAlphas   = PR_BIT(0) /**< Normal escape - leave alphas intact, escape the rest */
  56 ,       url_XPAlphas  = PR_BIT(1) /**< As url_XAlphas, but convert spaces (0x20) to '+' and plus to %2B */
  57 ,       url_Path      = PR_BIT(2) /**< As url_XAlphas, but don't escape slash ('/') */
  58 } nsEscapeMask;
  59
  60 #ifdef __cplusplus
  61 extern "C" {
  62 #endif
  63
  64 /**
  65  * Escape the given string according to mask
  66  * @param str The string to escape
  67  * @param mask How to escape the string
  68  * @return A newly allocated escaped string that must be free'd with
  69  *         nsCRT::free, or null on failure
  70  */
  71 NS_COM char * nsEscape(const char * str, nsEscapeMask mask);
  72
  73 NS_COM char * nsUnescape(char * str);
  74         /* decode % escaped hex codes into character values,
  75          * modifies the parameter, returns the same buffer
  76          */
  77
  78 NS_COM PRInt32 nsUnescapeCount (char * str);
  79         /* decode % escaped hex codes into character values,
  80          * modifies the parameter buffer, returns the length of the result
  81          * (result may contain \0's).
  82          */
  83
  84 NS_COM char *
  85 nsEscapeHTML(const char * string);
  86
  87 NS_COM PRUnichar *
  88 nsEscapeHTML2(const PRUnichar *aSourceBuffer,
  89               PRInt32 aSourceBufferLen = -1);
  90  /*
  91   * Escape problem char's for HTML display
  92   */
  93
  94
  95 #ifdef __cplusplus
  96 }
  97 #endif
  98
  99
 100 /**
 101  * NS_EscapeURL/NS_UnescapeURL constants for |flags| parameter:
 102  *
 103  * Note: These values are copied to nsINetUtil.idl
 104  *       Any changes should be kept in sync
 105  */
 106 enum EscapeMask {
 107   /** url components **/
 108   esc_Scheme         = PR_BIT(0),
 109   esc_Username       = PR_BIT(1),
 110   esc_Password       = PR_BIT(2),
 111   esc_Host           = PR_BIT(3),
 112   esc_Directory      = PR_BIT(4),
 113   esc_FileBaseName   = PR_BIT(5),
 114   esc_FileExtension  = PR_BIT(6),
 115   esc_FilePath       = esc_Directory | esc_FileBaseName | esc_FileExtension,
 116   esc_Param          = PR_BIT(7),
 117   esc_Query          = PR_BIT(8),
 118   esc_Ref            = PR_BIT(9),
 119   /** special flags **/
 120   esc_Minimal        = esc_Scheme | esc_Username | esc_Password | esc_Host | esc_FilePath | esc_Param | esc_Query | esc_Ref,
 121   esc_Forced         = PR_BIT(10), /* forces escaping of existing escape sequences */
 122   esc_OnlyASCII      = PR_BIT(11), /* causes non-ascii octets to be skipped */
 123   esc_OnlyNonASCII   = PR_BIT(12), /* causes _graphic_ ascii octets (0x20-0x7E)
 124                                     * to be skipped when escaping. causes all
 125                                     * ascii octets (<= 0x7F) to be skipped when unescaping */
 126   esc_AlwaysCopy     = PR_BIT(13), /* copy input to result buf even if escaping is unnecessary */
 127   esc_Colon          = PR_BIT(14), /* forces escape of colon */
 128   esc_SkipControl    = PR_BIT(15)  /* skips C0 and DEL from unescaping */
 129 };
 130
 131 /**
 132  * NS_EscapeURL
 133  *
 134  * Escapes invalid char's in an URL segment.  Has no side-effect if the URL
 135  * segment is already escaped.  Otherwise, the escaped URL segment is appended
 136  * to |result|.
 137  *
 138  * @param  str     url segment string
 139  * @param  len     url segment string length (-1 if unknown)
 140  * @param  flags   url segment type flag
 141  * @param  result  result buffer, untouched if part is already escaped
 142  *
 143  * @return TRUE if escaping was performed, FALSE otherwise.
 144  */
 145 NS_COM PRBool NS_EscapeURL(const char *str,
 146                            PRInt32 len,
 147                            PRUint32 flags,
 148                            nsACString &result);
 149
 150 /**
 151  * Expands URL escape sequences... beware embedded null bytes!
 152  *
 153  * @param  str     url string to unescape
 154  * @param  len     length of |str|
 155  * @param  flags   only esc_OnlyNonASCII, esc_SkipControl and esc_AlwaysCopy
 156  *                 are recognized
 157  * @param  result  result buffer, untouched if |str| is already unescaped
 158  *
 159  * @return TRUE if unescaping was performed, FALSE otherwise.
 160  */
 161 NS_COM PRBool NS_UnescapeURL(const char *str,
 162                              PRInt32 len,
 163                              PRUint32 flags,
 164                              nsACString &result);
 165
 166 /** returns resultant string length **/
 167 inline PRInt32 NS_UnescapeURL(char *str) {
 168     return nsUnescapeCount(str);
 169 }
 170
 171 /**
 172  * String friendly versions...
 173  */
 174 inline const nsCSubstring &
 175 NS_EscapeURL(const nsCSubstring &str, PRUint32 flags, nsCSubstring &result) {
 176     if (NS_EscapeURL(str.Data(), str.Length(), flags, result))
 177         return result;
 178     return str;
 179 }
 180 inline const nsCSubstring &
 181 NS_UnescapeURL(const nsCSubstring &str, PRUint32 flags, nsCSubstring &result) {
 182     if (NS_UnescapeURL(str.Data(), str.Length(), flags, result))
 183         return result;
 184     return str;
 185 }
 186
 187 /**
 188  * CString version of nsEscape. Returns true on success, false
 189  * on out of memory. To reverse this function, use NS_UnescapeURL.
 190  */
 191 inline PRBool
 192 NS_Escape(const nsCString& aOriginal, nsCString& aEscaped,
 193           nsEscapeMask aMask)
 194 {
 195   char* esc = nsEscape(aOriginal.get(), aMask);
 196   if (! esc)
 197     return PR_FALSE;
 198   aEscaped.Adopt(esc);
 199   return PR_TRUE;
 200 }
 201
 202 /**
 203  * Inline unescape of mutable string object.
 204  */
 205 inline nsCString &
 206 NS_UnescapeURL(nsCString &str)
 207 {
 208     str.SetLength(nsUnescapeCount(str.BeginWriting()));
 209     return str;
 210 }
 211
 212 #endif //  _ESCAPE_H_