1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* 3 * The contents of this file are subject to the Mozilla Public 4 * License Version 1.1 (the "License"); you may not use this file 5 * except in compliance with the License. You may obtain a copy of 6 * the License at http://www.mozilla.org/MPL/ 7 * 8 * Software distributed under the License is distributed on an "AS 9 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or 10 * implied. See the License for the specific language governing 11 * rights and limitations under the License. 12 * 13 * The Original Code is the Netscape Portable Runtime (NSPR). 14 * 15 * The Initial Developer of the Original Code is Netscape 16 * Communications Corporation. Portions created by Netscape are 17 * Copyright (C) 1998-2000 Netscape Communications Corporation. All 18 * Rights Reserved. 19 * 20 * Contributor(s): 21 * 22 * Alternatively, the contents of this file may be used under the 23 * terms of the GNU General Public License Version 2 or later (the 24 * "GPL"), in which case the provisions of the GPL are applicable 25 * instead of those above. If you wish to allow use of your 26 * version of this file only under the terms of the GPL and not to 27 * allow others to use your version of this file under the MPL, 28 * indicate your decision by deleting the provisions above and 29 * replace them with the notice and other provisions required by 30 * the GPL. If you do not delete the provisions above, a recipient 31 * may use your version of this file under either the MPL or the 32 * GPL. 33 */ 34 35 #ifndef prerror_h___ 36 #define prerror_h___ 37 38 #include "prtypes.h" 39 40 PR_BEGIN_EXTERN_C 41 42 typedef PRInt32 PRErrorCode; 43 44 #define PR_NSPR_ERROR_BASE -6000 45 46 #include "prerr.h" 47 48 /* 49 ** Set error will preserve an error condition within a thread context. 50 ** The values stored are the NSPR (platform independent) translation of 51 ** the error. Also, if available, the platform specific oserror is stored. 52 ** If there is no appropriate OS error number, a zero my be supplied. 53 */ 54 NSPR_API(void) PR_SetError(PRErrorCode errorCode, PRInt32 oserr); 55 56 /* 57 ** The text value specified may be NULL. If it is not NULL and the text length 58 ** is zero, the string is assumed to be a null terminated C string. Otherwise 59 ** the text is assumed to be the length specified and possibly include NULL 60 ** characters (e.g., a multi-national string). 61 ** 62 ** The text will be copied into to thread structure and remain there 63 ** until the next call to PR_SetError. 64 */ 65 NSPR_API(void) PR_SetErrorText( 66 PRIntn textLength, const char *text); 67 68 /* 69 ** Return the current threads last set error code. 70 */ 71 NSPR_API(PRErrorCode) PR_GetError(void); 72 73 /* 74 ** Return the current threads last set os error code. This is used for 75 ** machine specific code that desires the underlying os error. 76 */ 77 NSPR_API(PRInt32) PR_GetOSError(void); 78 79 /* 80 ** Get the length of the error text. If a zero is returned, then there 81 ** is no text. Otherwise, the value returned is sufficient to contain 82 ** the error text currently available. 83 */ 84 NSPR_API(PRInt32) PR_GetErrorTextLength(void); 85 86 /* 87 ** Copy the current threads current error text. Then actual number of bytes 88 ** copied is returned as the result. If the result is zero, the 'text' area 89 ** is unaffected. 90 */ 91 NSPR_API(PRInt32) PR_GetErrorText(char *text); 92 93 94 /* 95 Copyright (C) 1987, 1988 Student Information Processing Board of the 96 Massachusetts Institute of Technology. 97 98 Permission to use, copy, modify, and distribute this software and its 99 documentation for any purpose and without fee is hereby granted, provided 100 that the above copyright notice appear in all copies and that both that 101 copyright notice and this permission notice appear in supporting 102 documentation, and that the names of M.I.T. and the M.I.T. S.I.P.B. not be 103 used in advertising or publicity pertaining to distribution of the software 104 without specific, written prior permission. M.I.T. and the M.I.T. S.I.P.B. 105 make no representations about the suitability of this software for any 106 purpose. It is provided "as is" without express or implied warranty. 107 */ 108 109 110 /* 111 * NOTE: 112 * The interfaces for error-code-translation described in the rest of 113 * this file are preliminary in the 3.1 release of nspr and are subject 114 * to change in future releases. 115 */ 116 117 /* 118 ** Description: Localizable error code to string function. 119 ** 120 ** 121 ** NSPR provides a mechanism for converting an error code to a 122 ** descriptive string, in a caller-specified language. 123 ** 124 ** Error codes themselves are 32 bit (signed) integers. Typically, 125 ** the high order 24 bits are an identifier of which error table the 126 ** error code is from, and the low order 8 bits are a sequential error 127 ** number within the table. NSPR supports error tables whose first 128 ** error code is not a multiple of 256, such error code assignments 129 ** should be avoided when possible. 130 ** 131 ** Error table 0 is defined to match the UNIX system call error table 132 ** (sys_errlist); this allows errno values to be used directly in the 133 ** library. Other error table numbers are typically formed by 134 ** compacting together the first four characters of the error table 135 ** name. The mapping between characters in the name and numeric 136 ** values in the error code are defined in a system-independent 137 ** fashion, so that two systems that can pass integral values between 138 ** them can reliably pass error codes without loss of meaning; this 139 ** should work even if the character sets used are not the 140 ** same. (However, if this is to be done, error table 0 should be 141 ** avoided, since the local system call error tables may differ.) 142 ** 143 ** Libraries defining error codes need only provide a table mapping 144 ** error code numbers to names and default English descriptions, 145 ** calling a routine to install the table, making it ``known'' to NSPR 146 ** library. Once installed, a table may not be removed. Any error 147 ** code the library generates can be converted to the corresponding 148 ** error message. There is also a default format for error codes 149 ** accidentally returned before making the table known, which is of 150 ** the form "unknown code foo 32", where "foo" would be the name of 151 ** the table. 152 ** 153 ** Normally, the error code conversion routine only supports the 154 ** languages "i-default" and "en", returning the error-table-provided 155 ** English description for both languages. The application may 156 ** provide a localization plugin, allowing support for additional 157 ** languages. 158 ** 159 **/ 160 161 /**********************************************************************/ 162 /************************* TYPES AND CONSTANTS ************************/ 163 /**********************************************************************/ 164 165 /* 166 * PRLanguageCode -- 167 * 168 * NSPR represents a language code as a non-negative integer. 169 * Languages 0 is always "i-default" the language you get without 170 * explicit negotiation. Language 1 is always "en", English 171 * which has been explicitly negotiated. Additional language 172 * codes are defined by an application-provided localization plugin. 173 */ 174 typedef PRUint32 PRLanguageCode; 175 #define PR_LANGUAGE_I_DEFAULT 0 /* i-default, the default language */ 176 #define PR_LANGUAGE_EN 1 /* English, explicitly negotiated */ 177 178 /* 179 * struct PRErrorMessage -- 180 * 181 * An error message in an error table. 182 */ 183 struct PRErrorMessage { 184 const char * name; /* Macro name for error */ 185 const char * en_text; /* Default English text */ 186 }; 187 188 /* 189 * struct PRErrorTable -- 190 * 191 * An error table, provided by a library. 192 */ 193 struct PRErrorTable { 194 const struct PRErrorMessage * msgs; /* Array of error information */ 195 const char *name; /* Name of error table source */ 196 PRErrorCode base; /* Error code for first error in table */ 197 int n_msgs; /* Number of codes in table */ 198 }; 199 200 /* 201 * struct PRErrorCallbackPrivate -- 202 * 203 * A private structure for the localization plugin 204 */ 205 struct PRErrorCallbackPrivate; 206 207 /* 208 * struct PRErrorCallbackTablePrivate -- 209 * 210 * A data structure under which the localization plugin may store information, 211 * associated with an error table, that is private to itself. 212 */ 213 struct PRErrorCallbackTablePrivate; 214 215 /* 216 * PRErrorCallbackLookupFn -- 217 * 218 * A function of PRErrorCallbackLookupFn type is a localization 219 * plugin callback which converts an error code into a description 220 * in the requested language. The callback is provided the 221 * appropriate error table, private data for the plugin and the table. 222 * The callback returns the appropriate UTF-8 encoded description, or NULL 223 * if no description can be found. 224 */ 225 typedef const char * 226 PRErrorCallbackLookupFn(PRErrorCode code, PRLanguageCode language, 227 const struct PRErrorTable *table, 228 struct PRErrorCallbackPrivate *cb_private, 229 struct PRErrorCallbackTablePrivate *table_private); 230 231 /* 232 * PRErrorCallbackNewTableFn -- 233 * 234 * A function PRErrorCallbackNewTableFn type is a localization plugin 235 * callback which is called once with each error table registered 236 * with NSPR. The callback is provided with the error table and 237 * the plugin's private structure. The callback returns any table private 238 * data it wishes to associate with the error table. Does not need to be thread 239 * safe. 240 */ 241 typedef struct PRErrorCallbackTablePrivate * 242 PRErrorCallbackNewTableFn(const struct PRErrorTable *table, 243 struct PRErrorCallbackPrivate *cb_private); 244 245 /**********************************************************************/ 246 /****************************** FUNCTIONS *****************************/ 247 /**********************************************************************/ 248 249 /*********************************************************************** 250 ** FUNCTION: PR_ErrorToString 251 ** DESCRIPTION: 252 ** Returns the UTF-8 message for an error code in 253 ** the requested language. May return the message 254 ** in the default language if a translation in the requested 255 ** language is not available. The returned string is 256 ** valid for the duration of the process. Never returns NULL. 257 ** 258 ***********************************************************************/ 259 NSPR_API(const char *) PR_ErrorToString(PRErrorCode code, 260 PRLanguageCode language); 261 262 263 /*********************************************************************** 264 ** FUNCTION: PR_ErrorToName 265 ** DESCRIPTION: 266 ** Returns the macro name for an error code, or NULL 267 ** if the error code is not known. The returned string is 268 ** valid for the duration of the process. 269 ** 270 ** Does not work for error table 0, the system error codes. 271 ** 272 ***********************************************************************/ 273 NSPR_API(const char *) PR_ErrorToName(PRErrorCode code); 274 275 276 /*********************************************************************** 277 ** FUNCTION: PR_ErrorLanguages 278 ** DESCRIPTION: 279 ** Returns the RFC 1766 language tags for the language 280 ** codes PR_ErrorToString() supports. The returned array is valid 281 ** for the duration of the process. Never returns NULL. The first 282 ** item in the returned array is the language tag for PRLanguageCode 0, 283 ** the second is for PRLanguageCode 1, and so on. The array is terminated 284 ** with a null pointer. 285 ** 286 ***********************************************************************/ 287 NSPR_API(const char * const *) PR_ErrorLanguages(void); 288 289 290 /*********************************************************************** 291 ** FUNCTION: PR_ErrorInstallTable 292 ** DESCRIPTION: 293 ** Registers an error table with NSPR. Must be done exactly once per 294 ** table. Memory pointed to by `table' must remain valid for the life 295 ** of the process. 296 ** 297 ** NOT THREAD SAFE! 298 ** 299 ***********************************************************************/ 300 NSPR_API(PRErrorCode) PR_ErrorInstallTable(const struct PRErrorTable *table); 301 302 303 /*********************************************************************** 304 ** FUNCTION: PR_ErrorInstallCallback 305 ** DESCRIPTION: 306 ** Registers an error localization plugin with NSPR. May be called 307 ** at most one time. `languages' contains the language codes supported 308 ** by this plugin. Languages 0 and 1 must be "i-default" and "en" 309 ** respectively. `lookup' and `newtable' contain pointers to 310 ** the plugin callback functions. `cb_private' contains any information 311 ** private to the plugin functions. 312 ** 313 ** NOT THREAD SAFE! 314 ** 315 ***********************************************************************/ 316 NSPR_API(void) PR_ErrorInstallCallback(const char * const * languages, 317 PRErrorCallbackLookupFn *lookup, 318 PRErrorCallbackNewTableFn *newtable, 319 struct PRErrorCallbackPrivate *cb_private); 320 321 PR_END_EXTERN_C 322 323 #endif /* prerror_h___ */ 324