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/* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil; -*- */
/*
* Copyright (c) 2008 litl, LLC
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include <config.h>
#include "jsapi-util.h"
#include "jsapi-wrapper.h"
#include "gi/gerror.h"
#include <util/log.h>
#include <string.h>
/*
* See:
* https://bugzilla.mozilla.org/show_bug.cgi?id=166436
* https://bugzilla.mozilla.org/show_bug.cgi?id=215173
*
* Very surprisingly, jsapi.h lacks any way to "throw new Error()"
*
* So here is an awful hack inspired by
* http://egachine.berlios.de/embedding-sm-best-practice/embedding-sm-best-practice.html#error-handling
*/
static void
G_GNUC_PRINTF(4, 0)
gjs_throw_valist(JSContext *context,
const char *error_class,
const char *error_name,
const char *format,
va_list args)
{
char *s;
bool result;
s = g_strdup_vprintf(format, args);
JSAutoCompartment compartment(context, gjs_get_import_global(context));
JS_BeginRequest(context);
if (JS_IsExceptionPending(context)) {
/* Often it's unclear whether a given jsapi.h function
* will throw an exception, so we will throw ourselves
* "just in case"; in those cases, we don't want to
* overwrite an exception that already exists.
* (Do log in case our second exception adds more info,
* but don't log as topic ERROR because if the exception is
* caught we don't want an ERROR in the logs.)
*/
gjs_debug(GJS_DEBUG_CONTEXT,
"Ignoring second exception: '%s'",
s);
g_free(s);
JS_EndRequest(context);
return;
}
JS::RootedObject constructor(context);
JS::RootedObject global(context, JS::CurrentGlobalOrNull(context));
JS::RootedValue v_constructor(context), exc_val(context);
JS::RootedObject new_exc(context);
JS::AutoValueArray<1> error_args(context);
result = false;
if (!gjs_string_from_utf8(context, s, -1, error_args[0])) {
JS_ReportErrorUTF8(context, "Failed to copy exception string");
goto out;
}
if (!JS_GetProperty(context, global, error_class, &v_constructor) ||
!v_constructor.isObject()) {
JS_ReportErrorUTF8(context, "??? Missing Error constructor in global object?");
goto out;
}
/* throw new Error(message) */
constructor = &v_constructor.toObject();
new_exc = JS_New(context, constructor, error_args);
if (new_exc == NULL)
goto out;
if (error_name != NULL) {
JS::RootedValue name_value(context);
if (!gjs_string_from_utf8(context, error_name, -1, &name_value) ||
!gjs_object_set_property(context, new_exc, GJS_STRING_NAME,
name_value))
goto out;
}
exc_val.setObject(*new_exc);
JS_SetPendingException(context, exc_val);
result = true;
out:
if (!result) {
/* try just reporting it to error handler? should not
* happen though pretty much
*/
JS_ReportErrorUTF8(context, "Failed to throw exception '%s'", s);
}
g_free(s);
JS_EndRequest(context);
}
/* Throws an exception, like "throw new Error(message)"
*
* If an exception is already set in the context, this will
* NOT overwrite it. That's an important semantic since
* we want the "root cause" exception. To overwrite,
* use JS_ClearPendingException() first.
*/
void
gjs_throw(JSContext *context,
const char *format,
...)
{
va_list args;
va_start(args, format);
gjs_throw_valist(context, "Error", NULL, format, args);
va_end(args);
}
/*
* Like gjs_throw, but allows to customize the error
* class and 'name' property. Mainly used for throwing TypeError instead of
* error.
*/
void
gjs_throw_custom(JSContext *context,
const char *error_class,
const char *error_name,
const char *format,
...)
{
va_list args;
va_start(args, format);
gjs_throw_valist(context, error_class, error_name, format, args);
va_end(args);
}
/**
* gjs_throw_literal:
*
* Similar to gjs_throw(), but does not treat its argument as
* a format string.
*/
void
gjs_throw_literal(JSContext *context,
const char *string)
{
gjs_throw(context, "%s", string);
}
/**
* gjs_throw_g_error:
*
* Convert a GError into a JavaScript Exception, and
* frees the GError. Differently from gjs_throw(), it
* will overwrite an existing exception, as it is used
* to report errors from C functions.
*/
void
gjs_throw_g_error (JSContext *context,
GError *error)
{
if (error == NULL)
return;
JS_BeginRequest(context);
JS::RootedValue err(context,
JS::ObjectOrNullValue(gjs_error_from_gerror(context, error, true)));
g_error_free (error);
if (!err.isNull())
JS_SetPendingException(context, err);
JS_EndRequest(context);
}
/**
* gjs_format_stack_trace:
* @cx: the #JSContext
* @saved_frame: a SavedFrame #JSObject
*
* Formats a stack trace as a string in filename encoding, suitable for
* printing to stderr. Ignores any errors.
*
* Returns: unique string in filename encoding, or nullptr if no stack trace
*/
GjsAutoChar
gjs_format_stack_trace(JSContext *cx,
JS::HandleObject saved_frame)
{
JS::AutoSaveExceptionState saved_exc(cx);
JS::RootedString stack_trace(cx);
GjsAutoJSChar stack_utf8(cx);
if (JS::BuildStackString(cx, saved_frame, &stack_trace, 2))
stack_utf8.reset(cx, JS_EncodeStringToUTF8(cx, stack_trace));
saved_exc.restore();
if (!stack_utf8)
return nullptr;
return g_filename_from_utf8(stack_utf8, -1, nullptr, nullptr, nullptr);
}
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