xpcom/base/ErrorNames.cpp

   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 #include "mozilla/ArrayUtils.h"
   8 #include "mozilla/ErrorNames.h"
   9 #include "nsString.h"
  10 #include "prerror.h"
  11
  12 // Get the GetErrorNameInternal method
  13 #include "ErrorNamesInternal.h"
  14
  15 namespace mozilla {
  16
  17 const char* GetStaticErrorName(nsresult rv) { return GetErrorNameInternal(rv); }
  18
  19 void GetErrorName(nsresult rv, nsACString& name) {
  20   if (const char* errorName = GetErrorNameInternal(rv)) {
  21     name.AssignASCII(errorName);
  22     return;
  23   }
  24
  25   bool isSecurityError = NS_ERROR_GET_MODULE(rv) == NS_ERROR_MODULE_SECURITY;
  26
  27   // NS_ERROR_MODULE_SECURITY is the only module that is "allowed" to
  28   // synthesize nsresult error codes that are not listed in ErrorList.h. (The
  29   // NS_ERROR_MODULE_SECURITY error codes are synthesized from NSPR error
  30   // codes.)
  31   MOZ_ASSERT(isSecurityError);
  32
  33   if (NS_SUCCEEDED(rv)) {
  34     name.AssignLiteral("NS_ERROR_GENERATE_SUCCESS(");
  35   } else {
  36     name.AssignLiteral("NS_ERROR_GENERATE_FAILURE(");
  37   }
  38
  39   if (isSecurityError) {
  40     name.AppendLiteral("NS_ERROR_MODULE_SECURITY");
  41   } else {
  42     // This should never happen given the assertion above, so we don't bother
  43     // trying to print a symbolic name for the module here.
  44     name.AppendInt(NS_ERROR_GET_MODULE(rv));
  45   }
  46
  47   name.AppendLiteral(", ");
  48
  49   const char* nsprName = nullptr;
  50   if (isSecurityError) {
  51     // Invert the logic from NSSErrorsService::GetXPCOMFromNSSError
  52     PRErrorCode nsprCode = -1 * static_cast<PRErrorCode>(NS_ERROR_GET_CODE(rv));
  53     nsprName = PR_ErrorToName(nsprCode);
  54
  55     // All NSPR error codes defined by NSPR or NSS should have a name mapping.
  56     MOZ_ASSERT(nsprName);
  57   }
  58
  59   if (nsprName) {
  60     name.AppendASCII(nsprName);
  61   } else {
  62     name.AppendInt(NS_ERROR_GET_CODE(rv));
  63   }
  64
  65   name.AppendLiteral(")");
  66 }
  67
  68 }  // namespace mozilla
  69
  70 extern "C" {
  71
  72 // This is an extern "C" binding for the GetErrorName method which is used by
  73 // the nsresult rust bindings in xpcom/rust/nserror.
  74 void Gecko_GetErrorName(nsresult aRv, nsACString& aName) {
  75   mozilla::GetErrorName(aRv, aName);
  76 }
  77 }