js/src/jsexn.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * vim: set ts=8 sts=2 et sw=2 tw=80:
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /*
   8  * JS runtime exception classes.
   9  */
  10
  11 #ifndef jsexn_h
  12 #define jsexn_h
  13
  14 #include "mozilla/Assertions.h"
  15
  16 #include "jspubtd.h"
  17 #include "jstypes.h"
  18 #include "NamespaceImports.h"
  19
  20 #include "js/ErrorReport.h"
  21 #include "js/Exception.h"
  22 #include "js/friend/ErrorMessages.h"  // JSErr_Limit
  23 #include "js/RootingAPI.h"
  24 #include "js/TypeDecls.h"
  25 #include "js/UniquePtr.h"
  26 #include "js/Utility.h"
  27
  28 extern const JSErrorFormatString js_ErrorFormatString[JSErr_Limit];
  29
  30 namespace js {
  31
  32 class ErrorObject;
  33
  34 UniquePtr<JSErrorNotes::Note> CopyErrorNote(JSContext* cx,
  35                                             JSErrorNotes::Note* note);
  36
  37 UniquePtr<JSErrorReport> CopyErrorReport(JSContext* cx, JSErrorReport* report);
  38
  39 bool CaptureStack(JSContext* cx, MutableHandleObject stack);
  40
  41 JSString* ComputeStackString(JSContext* cx);
  42
  43 /*
  44  * Given a JSErrorReport, check to see if there is an exception associated with
  45  * the error number.  If there is, then create an appropriate Error object,
  46  * set it as the pending exception.
  47  *
  48  * It's possible we fail (due to OOM or some other error) and end up setting
  49  * JSContext::unwrappedException to a different exception.
  50  * The original error described by reportp typically won't be reported anywhere
  51  * in this case.
  52  *
  53  * If the error code is unrecognized, or if we decided to do nothing in order to
  54  * avoid recursion, we simply return and this error is just being swept under
  55  * the rug.
  56  */
  57 extern void ErrorToException(JSContext* cx, JSErrorReport* reportp,
  58                              JSErrorCallback callback, void* userRef);
  59
  60 extern JSErrorReport* ErrorFromException(JSContext* cx, HandleObject obj);
  61
  62 /*
  63  * Make a copy of errobj parented to cx's compartment's global.
  64  *
  65  * errobj may be in a different compartment than cx, but it must be an Error
  66  * object (not a wrapper of one) and it must not be one of the standard error
  67  * prototype objects (errobj->getPrivate() must not be nullptr).
  68  */
  69 extern JSObject* CopyErrorObject(JSContext* cx,
  70                                  JS::Handle<ErrorObject*> errobj);
  71
  72 static_assert(
  73     JSEXN_ERR == 0 &&
  74         JSProto_Error + JSEXN_INTERNALERR == JSProto_InternalError &&
  75         JSProto_Error + JSEXN_AGGREGATEERR == JSProto_AggregateError &&
  76         JSProto_Error + JSEXN_EVALERR == JSProto_EvalError &&
  77         JSProto_Error + JSEXN_RANGEERR == JSProto_RangeError &&
  78         JSProto_Error + JSEXN_REFERENCEERR == JSProto_ReferenceError &&
  79         JSProto_Error + JSEXN_SYNTAXERR == JSProto_SyntaxError &&
  80         JSProto_Error + JSEXN_TYPEERR == JSProto_TypeError &&
  81         JSProto_Error + JSEXN_URIERR == JSProto_URIError &&
  82         JSProto_Error + JSEXN_DEBUGGEEWOULDRUN == JSProto_DebuggeeWouldRun &&
  83         JSProto_Error + JSEXN_WASMCOMPILEERROR == JSProto_CompileError &&
  84         JSProto_Error + JSEXN_WASMLINKERROR == JSProto_LinkError &&
  85         JSProto_Error + JSEXN_WASMRUNTIMEERROR == JSProto_RuntimeError &&
  86         JSEXN_WASMRUNTIMEERROR + 1 == JSEXN_WARN &&
  87         JSEXN_WARN + 1 == JSEXN_NOTE && JSEXN_NOTE + 1 == JSEXN_LIMIT,
  88     "GetExceptionProtoKey and ExnTypeFromProtoKey require that "
  89     "each corresponding JSExnType and JSProtoKey value be separated "
  90     "by the same constant value");
  91
  92 static inline constexpr JSProtoKey GetExceptionProtoKey(JSExnType exn) {
  93   MOZ_ASSERT(JSEXN_ERR <= exn);
  94   MOZ_ASSERT(exn < JSEXN_WARN);
  95   return JSProtoKey(JSProto_Error + int(exn));
  96 }
  97
  98 static inline JSExnType ExnTypeFromProtoKey(JSProtoKey key) {
  99   JSExnType type = static_cast<JSExnType>(key - JSProto_Error);
 100   MOZ_ASSERT(type >= JSEXN_ERR);
 101   MOZ_ASSERT(type < JSEXN_ERROR_LIMIT);
 102   return type;
 103 }
 104
 105 static inline bool IsErrorProtoKey(JSProtoKey key) {
 106   int type = key - JSProto_Error;
 107   return type >= JSEXN_ERR && type < JSEXN_ERROR_LIMIT;
 108 }
 109
 110 class AutoClearPendingException {
 111   JSContext* cx;
 112
 113  public:
 114   explicit AutoClearPendingException(JSContext* cxArg) : cx(cxArg) {}
 115
 116   ~AutoClearPendingException() { JS_ClearPendingException(cx); }
 117 };
 118
 119 extern const char* ValueToSourceForError(JSContext* cx, HandleValue val,
 120                                          JS::UniqueChars& bytes);
 121
 122 bool GetInternalError(JSContext* cx, unsigned errorNumber,
 123                       MutableHandleValue error);
 124 bool GetTypeError(JSContext* cx, unsigned errorNumber,
 125                   MutableHandleValue error);
 126 bool GetAggregateError(JSContext* cx, unsigned errorNumber,
 127                        MutableHandleValue error);
 128
 129 }  // namespace js
 130
 131 #endif /* jsexn_h */