1/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2/* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
5
6#ifndef prerror_h___
7#define prerror_h___
8
9#include "prtypes.h"
10
11PR_BEGIN_EXTERN_C
12
13typedef PRInt32 PRErrorCode;
14
15#define PR_NSPR_ERROR_BASE -6000
16
17#include "prerr.h"
18
19/*
20** Set error will preserve an error condition within a thread context.
21** The values stored are the NSPR (platform independent) translation of
22** the error. Also, if available, the platform specific oserror is stored.
23** If there is no appropriate OS error number, a zero my be supplied.
24*/
25NSPR_API(void) PR_SetError(PRErrorCode errorCode, PRInt32 oserr);
26
27/*
28** The text value specified may be NULL. If it is not NULL and the text length
29** is zero, the string is assumed to be a null terminated C string. Otherwise
30** the text is assumed to be the length specified and possibly include NULL
31** characters (e.g., a multi-national string).
32**
33** The text will be copied into to thread structure and remain there
34** until the next call to PR_SetError.
35*/
36NSPR_API(void) PR_SetErrorText(
37 PRIntn textLength, const char *text);
38
39/*
40** Return the current threads last set error code.
41*/
42NSPR_API(PRErrorCode) PR_GetError(void);
43
44/*
45** Return the current threads last set os error code. This is used for
46** machine specific code that desires the underlying os error.
47*/
48NSPR_API(PRInt32) PR_GetOSError(void);
49
50/*
51** Get the length of the error text. If a zero is returned, then there
52** is no text. Otherwise, the value returned is sufficient to contain
53** the error text currently available.
54*/
55NSPR_API(PRInt32) PR_GetErrorTextLength(void);
56
57/*
58** Copy the current threads current error text. Then actual number of bytes
59** copied is returned as the result. If the result is zero, the 'text' area
60** is unaffected.
61*/
62NSPR_API(PRInt32) PR_GetErrorText(char *text);
63
64
65/*
66Copyright (C) 1987, 1988 Student Information Processing Board of the
67Massachusetts Institute of Technology.
68
69Permission to use, copy, modify, and distribute this software and its
70documentation for any purpose and without fee is hereby granted, provided
71that the above copyright notice appear in all copies and that both that
72copyright notice and this permission notice appear in supporting
73documentation, and that the names of M.I.T. and the M.I.T. S.I.P.B. not be
74used in advertising or publicity pertaining to distribution of the software
75without specific, written prior permission. M.I.T. and the M.I.T. S.I.P.B.
76make no representations about the suitability of this software for any
77purpose. It is provided "as is" without express or implied warranty.
78*/
79
80
81/*
82 * NOTE:
83 * The interfaces for error-code-translation described in the rest of
84 * this file are preliminary in the 3.1 release of nspr and are subject
85 * to change in future releases.
86 */
87
88/*
89** Description: Localizable error code to string function.
90**
91**
92** NSPR provides a mechanism for converting an error code to a
93** descriptive string, in a caller-specified language.
94**
95** Error codes themselves are 32 bit (signed) integers. Typically,
96** the high order 24 bits are an identifier of which error table the
97** error code is from, and the low order 8 bits are a sequential error
98** number within the table. NSPR supports error tables whose first
99** error code is not a multiple of 256, such error code assignments
100** should be avoided when possible.
101**
102** Error table 0 is defined to match the UNIX system call error table
103** (sys_errlist); this allows errno values to be used directly in the
104** library. Other error table numbers are typically formed by
105** compacting together the first four characters of the error table
106** name. The mapping between characters in the name and numeric
107** values in the error code are defined in a system-independent
108** fashion, so that two systems that can pass integral values between
109** them can reliably pass error codes without loss of meaning; this
110** should work even if the character sets used are not the
111** same. (However, if this is to be done, error table 0 should be
112** avoided, since the local system call error tables may differ.)
113**
114** Libraries defining error codes need only provide a table mapping
115** error code numbers to names and default English descriptions,
116** calling a routine to install the table, making it ``known'' to NSPR
117** library. Once installed, a table may not be removed. Any error
118** code the library generates can be converted to the corresponding
119** error message. There is also a default format for error codes
120** accidentally returned before making the table known, which is of
121** the form "unknown code foo 32", where "foo" would be the name of
122** the table.
123**
124** Normally, the error code conversion routine only supports the
125** languages "i-default" and "en", returning the error-table-provided
126** English description for both languages. The application may
127** provide a localization plugin, allowing support for additional
128** languages.
129**
130**/
131
132/**********************************************************************/
133/************************* TYPES AND CONSTANTS ************************/
134/**********************************************************************/
135
136/*
137 * PRLanguageCode --
138 *
139 * NSPR represents a language code as a non-negative integer.
140 * Languages 0 is always "i-default" the language you get without
141 * explicit negotiation. Language 1 is always "en", English
142 * which has been explicitly negotiated. Additional language
143 * codes are defined by an application-provided localization plugin.
144 */
145typedef PRUint32 PRLanguageCode;
146#define PR_LANGUAGE_I_DEFAULT 0 /* i-default, the default language */
147#define PR_LANGUAGE_EN 1 /* English, explicitly negotiated */
148
149/*
150 * struct PRErrorMessage --
151 *
152 * An error message in an error table.
153 */
154struct PRErrorMessage {
155 const char * name; /* Macro name for error */
156 const char * en_text; /* Default English text */
157};
158
159/*
160 * struct PRErrorTable --
161 *
162 * An error table, provided by a library.
163 */
164struct PRErrorTable {
165 const struct PRErrorMessage * msgs; /* Array of error information */
166 const char *name; /* Name of error table source */
167 PRErrorCode base; /* Error code for first error in table */
168 int n_msgs; /* Number of codes in table */
169};
170
171/*
172 * struct PRErrorCallbackPrivate --
173 *
174 * A private structure for the localization plugin
175 */
176struct PRErrorCallbackPrivate;
177
178/*
179 * struct PRErrorCallbackTablePrivate --
180 *
181 * A data structure under which the localization plugin may store information,
182 * associated with an error table, that is private to itself.
183 */
184struct PRErrorCallbackTablePrivate;
185
186/*
187 * PRErrorCallbackLookupFn --
188 *
189 * A function of PRErrorCallbackLookupFn type is a localization
190 * plugin callback which converts an error code into a description
191 * in the requested language. The callback is provided the
192 * appropriate error table, private data for the plugin and the table.
193 * The callback returns the appropriate UTF-8 encoded description, or NULL
194 * if no description can be found.
195 */
196typedef const char *
197PRErrorCallbackLookupFn(PRErrorCode code, PRLanguageCode language,
198 const struct PRErrorTable *table,
199 struct PRErrorCallbackPrivate *cb_private,
200 struct PRErrorCallbackTablePrivate *table_private);
201
202/*
203 * PRErrorCallbackNewTableFn --
204 *
205 * A function PRErrorCallbackNewTableFn type is a localization plugin
206 * callback which is called once with each error table registered
207 * with NSPR. The callback is provided with the error table and
208 * the plugin's private structure. The callback returns any table private
209 * data it wishes to associate with the error table. Does not need to be thread
210 * safe.
211 */
212typedef struct PRErrorCallbackTablePrivate *
213PRErrorCallbackNewTableFn(const struct PRErrorTable *table,
214 struct PRErrorCallbackPrivate *cb_private);
215
216/**********************************************************************/
217/****************************** FUNCTIONS *****************************/
218/**********************************************************************/
219
220/***********************************************************************
221** FUNCTION: PR_ErrorToString
222** DESCRIPTION:
223** Returns the UTF-8 message for an error code in
224** the requested language. May return the message
225** in the default language if a translation in the requested
226** language is not available. The returned string is
227** valid for the duration of the process. Never returns NULL.
228**
229***********************************************************************/
230NSPR_API(const char *) PR_ErrorToString(PRErrorCode code,
231 PRLanguageCode language);
232
233
234/***********************************************************************
235** FUNCTION: PR_ErrorToName
236** DESCRIPTION:
237** Returns the macro name for an error code, or NULL
238** if the error code is not known. The returned string is
239** valid for the duration of the process.
240**
241** Does not work for error table 0, the system error codes.
242**
243***********************************************************************/
244NSPR_API(const char *) PR_ErrorToName(PRErrorCode code);
245
246
247/***********************************************************************
248** FUNCTION: PR_ErrorLanguages
249** DESCRIPTION:
250** Returns the RFC 1766 language tags for the language
251** codes PR_ErrorToString() supports. The returned array is valid
252** for the duration of the process. Never returns NULL. The first
253** item in the returned array is the language tag for PRLanguageCode 0,
254** the second is for PRLanguageCode 1, and so on. The array is terminated
255** with a null pointer.
256**
257***********************************************************************/
258NSPR_API(const char * const *) PR_ErrorLanguages(void);
259
260
261/***********************************************************************
262** FUNCTION: PR_ErrorInstallTable
263** DESCRIPTION:
264** Registers an error table with NSPR. Must be done exactly once per
265** table. Memory pointed to by `table' must remain valid for the life
266** of the process.
267**
268** NOT THREAD SAFE!
269**
270***********************************************************************/
271NSPR_API(PRErrorCode) PR_ErrorInstallTable(const struct PRErrorTable *table);
272
273
274/***********************************************************************
275** FUNCTION: PR_ErrorInstallCallback
276** DESCRIPTION:
277** Registers an error localization plugin with NSPR. May be called
278** at most one time. `languages' contains the language codes supported
279** by this plugin. Languages 0 and 1 must be "i-default" and "en"
280** respectively. `lookup' and `newtable' contain pointers to
281** the plugin callback functions. `cb_private' contains any information
282** private to the plugin functions.
283**
284** NOT THREAD SAFE!
285**
286***********************************************************************/
287NSPR_API(void) PR_ErrorInstallCallback(const char * const * languages,
288 PRErrorCallbackLookupFn *lookup,
289 PRErrorCallbackNewTableFn *newtable,
290 struct PRErrorCallbackPrivate *cb_private);
291
292PR_END_EXTERN_C
293
294#endif /* prerror_h___ */
295

source code of include/nspr/prerror.h