gecko-dev/xpcom/base/nsError.h

262 lines
8.4 KiB
C

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsError_h__
#define nsError_h__
#include "mozilla/Likely.h"
#include "mozilla/TypedEnum.h"
#include <stdint.h>
/*
* To add error code to your module, you need to do the following:
*
* 1) Add a module offset code. Add yours to the bottom of the list
* right below this comment, adding 1.
*
* 2) In your module, define a header file which uses one of the
* NE_ERROR_GENERATExxxxxx macros. Some examples below:
*
* #define NS_ERROR_MYMODULE_MYERROR1 NS_ERROR_GENERATE(NS_ERROR_SEVERITY_ERROR,NS_ERROR_MODULE_MYMODULE,1)
* #define NS_ERROR_MYMODULE_MYERROR2 NS_ERROR_GENERATE_SUCCESS(NS_ERROR_MODULE_MYMODULE,2)
* #define NS_ERROR_MYMODULE_MYERROR3 NS_ERROR_GENERATE_FAILURE(NS_ERROR_MODULE_MYMODULE,3)
*
*/
/**
* @name Standard Module Offset Code. Each Module should identify a unique number
* and then all errors associated with that module become offsets from the
* base associated with that module id. There are 16 bits of code bits for
* each module.
*/
#define NS_ERROR_MODULE_XPCOM 1
#define NS_ERROR_MODULE_BASE 2
#define NS_ERROR_MODULE_GFX 3
#define NS_ERROR_MODULE_WIDGET 4
#define NS_ERROR_MODULE_CALENDAR 5
#define NS_ERROR_MODULE_NETWORK 6
#define NS_ERROR_MODULE_PLUGINS 7
#define NS_ERROR_MODULE_LAYOUT 8
#define NS_ERROR_MODULE_HTMLPARSER 9
#define NS_ERROR_MODULE_RDF 10
#define NS_ERROR_MODULE_UCONV 11
#define NS_ERROR_MODULE_REG 12
#define NS_ERROR_MODULE_FILES 13
#define NS_ERROR_MODULE_DOM 14
#define NS_ERROR_MODULE_IMGLIB 15
#define NS_ERROR_MODULE_MAILNEWS 16
#define NS_ERROR_MODULE_EDITOR 17
#define NS_ERROR_MODULE_XPCONNECT 18
#define NS_ERROR_MODULE_PROFILE 19
#define NS_ERROR_MODULE_LDAP 20
#define NS_ERROR_MODULE_SECURITY 21
#define NS_ERROR_MODULE_DOM_XPATH 22
/* 23 used to be NS_ERROR_MODULE_DOM_RANGE (see bug 711047) */
#define NS_ERROR_MODULE_URILOADER 24
#define NS_ERROR_MODULE_CONTENT 25
#define NS_ERROR_MODULE_PYXPCOM 26
#define NS_ERROR_MODULE_XSLT 27
#define NS_ERROR_MODULE_IPC 28
#define NS_ERROR_MODULE_SVG 29
#define NS_ERROR_MODULE_STORAGE 30
#define NS_ERROR_MODULE_SCHEMA 31
#define NS_ERROR_MODULE_DOM_FILE 32
#define NS_ERROR_MODULE_DOM_INDEXEDDB 33
#define NS_ERROR_MODULE_DOM_FILEHANDLE 34
#define NS_ERROR_MODULE_SIGNED_JAR 35
#define NS_ERROR_MODULE_DOM_FILESYSTEM 36
#define NS_ERROR_MODULE_DOM_BLUETOOTH 37
#define NS_ERROR_MODULE_SIGNED_APP 38
/* NS_ERROR_MODULE_GENERAL should be used by modules that do not
* care if return code values overlap. Callers of methods that
* return such codes should be aware that they are not
* globally unique. Implementors should be careful about blindly
* returning codes from other modules that might also use
* the generic base.
*/
#define NS_ERROR_MODULE_GENERAL 51
/**
* @name Severity Code. This flag identifies the level of warning
*/
#define NS_ERROR_SEVERITY_SUCCESS 0
#define NS_ERROR_SEVERITY_ERROR 1
/**
* @name Mozilla Code. This flag separates consumers of mozilla code
* from the native platform
*/
#define NS_ERROR_MODULE_BASE_OFFSET 0x45
/* Helpers for defining our enum, to be undef'd later */
#define SUCCESS_OR_FAILURE(sev, module, code) \
((uint32_t)(sev) << 31) | \
((uint32_t)(module + NS_ERROR_MODULE_BASE_OFFSET) << 16) | \
(uint32_t)(code)
#define SUCCESS(code) \
SUCCESS_OR_FAILURE(NS_ERROR_SEVERITY_SUCCESS, MODULE, code)
#define FAILURE(code) \
SUCCESS_OR_FAILURE(NS_ERROR_SEVERITY_ERROR, MODULE, code)
/**
* @name Standard return values
*/
/*@{*/
/* Unfortunately, our workaround for compilers that don't support enum class
* doesn't really work for nsresult. We need constants like NS_OK with type
* nsresult, but they can't be used in (e.g.) switch cases if they're objects.
* But if we define them to be of type nsresult::Enum instead, that causes
* return foo ? F() : NS_ERROR_FAILURE;
* to fail, because nsresult and nsresult::Enum are two distinct types and
* either can be converted to the other, so it's ambiguous. So we have to fall
* back to a regular enum.
*/
#if defined(MOZ_HAVE_CXX11_STRONG_ENUMS)
typedef enum class tag_nsresult : uint32_t
{
#undef ERROR
#define ERROR(key, val) key = val
#include "ErrorList.h"
#undef ERROR
} nsresult;
/*
* enum classes don't place their initializers in the global scope, so we need
* #define's for compatibility with old code.
*/
#include "ErrorListCxxDefines.h"
#elif defined(MOZ_HAVE_CXX11_ENUM_TYPE)
typedef enum tag_nsresult : uint32_t
{
#undef ERROR
#define ERROR(key, val) key = val
#include "ErrorList.h"
#undef ERROR
} nsresult;
#elif defined(__cplusplus)
/*
* We're C++ in an old compiler lacking enum classes *and* typed enums (likely
* gcc < 4.5.1 as clang/MSVC have long supported one or both), or compiler
* support is unknown. Yet nsresult must have unsigned 32-bit representation.
* So just make it a typedef, and implement the constants with global consts.
*/
typedef uint32_t nsresult;
const nsresult
#undef ERROR
#define ERROR(key, val) key = val
#include "ErrorList.h"
#undef ERROR
;
#else
/*
* C doesn't have any way to fix the type underlying an enum, and enum
* initializers can't have values outside the range of 'int'. So typedef
* nsresult to the correct unsigned type, and fall back to using #defines for
* all error constants.
*/
typedef uint32_t nsresult;
#include "ErrorListCDefines.h"
#endif
#undef SUCCESS_OR_FAILURE
#undef SUCCESS
#undef FAILURE
/**
* @name Standard Error Handling Macros
* @return 0 or 1 (false/true with bool type for C++)
*/
#ifdef __cplusplus
inline uint32_t
NS_FAILED_impl(nsresult aErr)
{
return static_cast<uint32_t>(aErr) & 0x80000000;
}
#define NS_FAILED(_nsresult) ((bool)MOZ_UNLIKELY(NS_FAILED_impl(_nsresult)))
#define NS_SUCCEEDED(_nsresult) ((bool)MOZ_LIKELY(!NS_FAILED_impl(_nsresult)))
/* Check that our enum type is actually uint32_t as expected */
static_assert(((nsresult)0) < ((nsresult)-1),
"nsresult must be an unsigned type");
static_assert(sizeof(nsresult) == sizeof(uint32_t),
"nsresult must be 32 bits");
#else
#define NS_FAILED_impl(_nsresult) ((_nsresult) & 0x80000000)
#define NS_FAILED(_nsresult) (MOZ_UNLIKELY(NS_FAILED_impl(_nsresult)))
#define NS_SUCCEEDED(_nsresult) (MOZ_LIKELY(!NS_FAILED_impl(_nsresult)))
#endif
/**
* @name Standard Error Generating Macros
*/
#define NS_ERROR_GENERATE(sev, module, code) \
(nsresult)(((uint32_t)(sev) << 31) | \
((uint32_t)(module + NS_ERROR_MODULE_BASE_OFFSET) << 16) | \
((uint32_t)(code)))
#define NS_ERROR_GENERATE_SUCCESS(module, code) \
NS_ERROR_GENERATE(NS_ERROR_SEVERITY_SUCCESS, module, code)
#define NS_ERROR_GENERATE_FAILURE(module, code) \
NS_ERROR_GENERATE(NS_ERROR_SEVERITY_ERROR, module, code)
/*
* This will return the nsresult corresponding to the most recent NSPR failure
* returned by PR_GetError.
*
***********************************************************************
* Do not depend on this function. It will be going away!
***********************************************************************
*/
extern nsresult
NS_ErrorAccordingToNSPR();
/**
* @name Standard Macros for retrieving error bits
*/
#ifdef __cplusplus
inline uint16_t
NS_ERROR_GET_CODE(nsresult aErr)
{
return uint32_t(aErr) & 0xffff;
}
inline uint16_t
NS_ERROR_GET_MODULE(nsresult aErr)
{
return ((uint32_t(aErr) >> 16) - NS_ERROR_MODULE_BASE_OFFSET) & 0x1fff;
}
inline bool
NS_ERROR_GET_SEVERITY(nsresult aErr)
{
return uint32_t(aErr) >> 31;
}
#else
#define NS_ERROR_GET_CODE(err) ((err) & 0xffff)
#define NS_ERROR_GET_MODULE(err) ((((err) >> 16) - NS_ERROR_MODULE_BASE_OFFSET) & 0x1fff)
#define NS_ERROR_GET_SEVERITY(err) (((err) >> 31) & 0x1)
#endif
#ifdef _MSC_VER
#pragma warning(disable: 4251) /* 'nsCOMPtr<class nsIInputStream>' needs to have dll-interface to be used by clients of class 'nsInputStream' */
#pragma warning(disable: 4275) /* non dll-interface class 'nsISupports' used as base for dll-interface class 'nsIRDFNode' */
#endif
#endif