1/*
2 * Copyright (C) 2004, 2008, 2009 Apple Inc. All rights reserved.
3 * Copyright (C) 2008 Collabora Ltd.
4 * Copyright (C) 2011 Peter Varga (pvarga@webkit.org), University of Szeged
5 * Copyright (C) 2013 Google Inc. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
17 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
20 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
23 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
24 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include "config.h"
30#include "bindings/core/v8/ScriptRegexp.h"
31
32#include "bindings/core/v8/V8Binding.h"
33#include "bindings/core/v8/V8PerIsolateData.h"
34#include "bindings/core/v8/V8ScriptRunner.h"
35#include "platform/ScriptForbiddenScope.h"
36
37namespace blink {
38
39ScriptRegexp::ScriptRegexp(const String& pattern, TextCaseSensitivity caseSensitivity, MultilineMode multilineMode)
40{
41    v8::Isolate* isolate = v8::Isolate::GetCurrent();
42    v8::HandleScope handleScope(isolate);
43    v8::Context::Scope contextScope(V8PerIsolateData::from(isolate)->ensureScriptRegexpContext());
44    v8::TryCatch tryCatch;
45
46    unsigned flags = v8::RegExp::kNone;
47    if (caseSensitivity == TextCaseInsensitive)
48        flags |= v8::RegExp::kIgnoreCase;
49    if (multilineMode == MultilineEnabled)
50        flags |= v8::RegExp::kMultiline;
51
52    v8::Local<v8::RegExp> regex = v8::RegExp::New(v8String(isolate, pattern), static_cast<v8::RegExp::Flags>(flags));
53
54    // If the regex failed to compile we'll get an empty handle.
55    if (!regex.IsEmpty())
56        m_regex.set(isolate, regex);
57}
58
59int ScriptRegexp::match(const String& string, int startFrom, int* matchLength) const
60{
61    if (matchLength)
62        *matchLength = 0;
63
64    if (m_regex.isEmpty() || string.isNull())
65        return -1;
66
67    // v8 strings are limited to int.
68    if (string.length() > INT_MAX)
69        return -1;
70
71    ScriptForbiddenScope::AllowUserAgentScript allowScript;
72
73    v8::Isolate* isolate = v8::Isolate::GetCurrent();
74    v8::HandleScope handleScope(isolate);
75    v8::Context::Scope contextScope(V8PerIsolateData::from(isolate)->ensureScriptRegexpContext());
76    v8::TryCatch tryCatch;
77
78    v8::Local<v8::RegExp> regex = m_regex.newLocal(isolate);
79    v8::Local<v8::Function> exec = regex->Get(v8AtomicString(isolate, "exec")).As<v8::Function>();
80    v8::Handle<v8::Value> argv[] = { v8String(isolate, string.substring(startFrom)) };
81    v8::Local<v8::Value> returnValue = V8ScriptRunner::callInternalFunction(exec, regex, WTF_ARRAY_LENGTH(argv), argv, isolate);
82
83    if (tryCatch.HasCaught())
84        return -1;
85
86    // RegExp#exec returns null if there's no match, otherwise it returns an
87    // Array of strings with the first being the whole match string and others
88    // being subgroups. The Array also has some random properties tacked on like
89    // "index" which is the offset of the match.
90    //
91    // https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/RegExp/exec
92
93    ASSERT(!returnValue.IsEmpty());
94    if (!returnValue->IsArray())
95        return -1;
96
97    v8::Local<v8::Array> result = returnValue.As<v8::Array>();
98    int matchOffset = result->Get(v8AtomicString(isolate, "index"))->ToInt32()->Value();
99    if (matchLength) {
100        v8::Local<v8::String> match = result->Get(0).As<v8::String>();
101        *matchLength = match->Length();
102    }
103
104    return matchOffset + startFrom;
105}
106
107} // namespace blink
108