1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "base/android/jni_string.h"
6
7#include "base/android/jni_android.h"
8#include "base/logging.h"
9#include "base/strings/utf_string_conversions.h"
10
11namespace {
12
13// Internal version that does not use a scoped local pointer.
14jstring ConvertUTF16ToJavaStringImpl(JNIEnv* env,
15                                     const base::StringPiece16& str) {
16  jstring result = env->NewString(str.data(), str.length());
17  base::android::CheckException(env);
18  return result;
19}
20
21}  // namespace
22
23namespace base {
24namespace android {
25
26void ConvertJavaStringToUTF8(JNIEnv* env, jstring str, std::string* result) {
27  DCHECK(str);
28  if (!str) {
29    LOG(WARNING) << "ConvertJavaStringToUTF8 called with null string.";
30    result->clear();
31    return;
32  }
33  const jsize length = env->GetStringLength(str);
34  if (!length) {
35    result->clear();
36    CheckException(env);
37    return;
38  }
39  // JNI's GetStringUTFChars() returns strings in Java "modified" UTF8, so
40  // instead get the String in UTF16 and convert using chromium's conversion
41  // function that yields plain (non Java-modified) UTF8.
42  const jchar* chars = env->GetStringChars(str, NULL);
43  DCHECK(chars);
44  UTF16ToUTF8(chars, length, result);
45  env->ReleaseStringChars(str, chars);
46  CheckException(env);
47}
48
49std::string ConvertJavaStringToUTF8(JNIEnv* env, jstring str) {
50  std::string result;
51  ConvertJavaStringToUTF8(env, str, &result);
52  return result;
53}
54
55std::string ConvertJavaStringToUTF8(const JavaRef<jstring>& str) {
56  return ConvertJavaStringToUTF8(AttachCurrentThread(), str.obj());
57}
58
59std::string ConvertJavaStringToUTF8(JNIEnv* env, const JavaRef<jstring>& str) {
60  return ConvertJavaStringToUTF8(env, str.obj());
61}
62
63ScopedJavaLocalRef<jstring> ConvertUTF8ToJavaString(
64    JNIEnv* env,
65    const base::StringPiece& str) {
66  // JNI's NewStringUTF expects "modified" UTF8 so instead create the string
67  // via our own UTF16 conversion utility.
68  // Further, Dalvik requires the string passed into NewStringUTF() to come from
69  // a trusted source. We can't guarantee that all UTF8 will be sanitized before
70  // it gets here, so constructing via UTF16 side-steps this issue.
71  // (Dalvik stores strings internally as UTF16 anyway, so there shouldn't be
72  // a significant performance hit by doing it this way).
73  return ScopedJavaLocalRef<jstring>(env, ConvertUTF16ToJavaStringImpl(
74      env, UTF8ToUTF16(str)));
75}
76
77void ConvertJavaStringToUTF16(JNIEnv* env, jstring str, string16* result) {
78  DCHECK(str);
79  if (!str) {
80    LOG(WARNING) << "ConvertJavaStringToUTF16 called with null string.";
81    result->clear();
82    return;
83  }
84  const jsize length = env->GetStringLength(str);
85  if (!length) {
86    result->clear();
87    CheckException(env);
88    return;
89  }
90  const jchar* chars = env->GetStringChars(str, NULL);
91  DCHECK(chars);
92  // GetStringChars isn't required to NULL-terminate the strings
93  // it returns, so the length must be explicitly checked.
94  result->assign(chars, length);
95  env->ReleaseStringChars(str, chars);
96  CheckException(env);
97}
98
99string16 ConvertJavaStringToUTF16(JNIEnv* env, jstring str) {
100  string16 result;
101  ConvertJavaStringToUTF16(env, str, &result);
102  return result;
103}
104
105string16 ConvertJavaStringToUTF16(const JavaRef<jstring>& str) {
106  return ConvertJavaStringToUTF16(AttachCurrentThread(), str.obj());
107}
108
109string16 ConvertJavaStringToUTF16(JNIEnv* env, const JavaRef<jstring>& str) {
110  return ConvertJavaStringToUTF16(env, str.obj());
111}
112
113ScopedJavaLocalRef<jstring> ConvertUTF16ToJavaString(
114    JNIEnv* env,
115    const base::StringPiece16& str) {
116  return ScopedJavaLocalRef<jstring>(env,
117                                     ConvertUTF16ToJavaStringImpl(env, str));
118}
119
120}  // namespace android
121}  // namespace base
122