1 // Copyright 2012 The Chromium Authors
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/numerics/safe_conversions.h"
10 #include "base/strings/utf_string_conversions.h"
11
12 namespace {
13
14 // Internal version that does not use a scoped local pointer.
ConvertUTF16ToJavaStringImpl(JNIEnv * env,const base::StringPiece16 & str)15 jstring ConvertUTF16ToJavaStringImpl(JNIEnv* env,
16 const base::StringPiece16& str) {
17 jstring result = env->NewString(reinterpret_cast<const jchar*>(str.data()),
18 base::checked_cast<jsize>(str.length()));
19 base::android::CheckException(env);
20 return result;
21 }
22
23 } // namespace
24
25 namespace base {
26 namespace android {
27
ConvertJavaStringToUTF8(JNIEnv * env,jstring str,std::string * result)28 void ConvertJavaStringToUTF8(JNIEnv* env, jstring str, std::string* result) {
29 DCHECK(str);
30 if (!str) {
31 LOG(WARNING) << "ConvertJavaStringToUTF8 called with null string.";
32 result->clear();
33 return;
34 }
35 const jsize length = env->GetStringLength(str);
36 if (length <= 0) {
37 result->clear();
38 CheckException(env);
39 return;
40 }
41 // JNI's GetStringUTFChars() returns strings in Java "modified" UTF8, so
42 // instead get the String in UTF16 and convert using chromium's conversion
43 // function that yields plain (non Java-modified) UTF8.
44 const jchar* chars = env->GetStringChars(str, NULL);
45 DCHECK(chars);
46 UTF16ToUTF8(reinterpret_cast<const char16_t*>(chars),
47 static_cast<size_t>(length), result);
48 env->ReleaseStringChars(str, chars);
49 CheckException(env);
50 }
51
ConvertJavaStringToUTF8(JNIEnv * env,jstring str)52 std::string ConvertJavaStringToUTF8(JNIEnv* env, jstring str) {
53 std::string result;
54 ConvertJavaStringToUTF8(env, str, &result);
55 return result;
56 }
57
ConvertJavaStringToUTF8(const JavaRef<jstring> & str)58 std::string ConvertJavaStringToUTF8(const JavaRef<jstring>& str) {
59 return ConvertJavaStringToUTF8(AttachCurrentThread(), str.obj());
60 }
61
ConvertJavaStringToUTF8(JNIEnv * env,const JavaRef<jstring> & str)62 std::string ConvertJavaStringToUTF8(JNIEnv* env, const JavaRef<jstring>& str) {
63 return ConvertJavaStringToUTF8(env, str.obj());
64 }
65
ConvertUTF8ToJavaString(JNIEnv * env,const StringPiece & str)66 ScopedJavaLocalRef<jstring> ConvertUTF8ToJavaString(JNIEnv* env,
67 const StringPiece& str) {
68 // JNI's NewStringUTF expects "modified" UTF8 so instead create the string
69 // via our own UTF16 conversion utility.
70 // Further, Dalvik requires the string passed into NewStringUTF() to come from
71 // a trusted source. We can't guarantee that all UTF8 will be sanitized before
72 // it gets here, so constructing via UTF16 side-steps this issue.
73 // (Dalvik stores strings internally as UTF16 anyway, so there shouldn't be
74 // a significant performance hit by doing it this way).
75 return ScopedJavaLocalRef<jstring>(env, ConvertUTF16ToJavaStringImpl(
76 env, UTF8ToUTF16(str)));
77 }
78
ConvertJavaStringToUTF16(JNIEnv * env,jstring str,std::u16string * result)79 void ConvertJavaStringToUTF16(JNIEnv* env,
80 jstring str,
81 std::u16string* result) {
82 DCHECK(str);
83 if (!str) {
84 LOG(WARNING) << "ConvertJavaStringToUTF16 called with null string.";
85 result->clear();
86 return;
87 }
88 const jsize length = env->GetStringLength(str);
89 if (length <= 0) {
90 result->clear();
91 CheckException(env);
92 return;
93 }
94 const jchar* chars = env->GetStringChars(str, NULL);
95 DCHECK(chars);
96 // GetStringChars isn't required to NULL-terminate the strings
97 // it returns, so the length must be explicitly checked.
98 result->assign(reinterpret_cast<const char16_t*>(chars),
99 static_cast<size_t>(length));
100 env->ReleaseStringChars(str, chars);
101 CheckException(env);
102 }
103
ConvertJavaStringToUTF16(JNIEnv * env,jstring str)104 std::u16string ConvertJavaStringToUTF16(JNIEnv* env, jstring str) {
105 std::u16string result;
106 ConvertJavaStringToUTF16(env, str, &result);
107 return result;
108 }
109
ConvertJavaStringToUTF16(const JavaRef<jstring> & str)110 std::u16string ConvertJavaStringToUTF16(const JavaRef<jstring>& str) {
111 return ConvertJavaStringToUTF16(AttachCurrentThread(), str.obj());
112 }
113
ConvertJavaStringToUTF16(JNIEnv * env,const JavaRef<jstring> & str)114 std::u16string ConvertJavaStringToUTF16(JNIEnv* env,
115 const JavaRef<jstring>& str) {
116 return ConvertJavaStringToUTF16(env, str.obj());
117 }
118
ConvertUTF16ToJavaString(JNIEnv * env,const StringPiece16 & str)119 ScopedJavaLocalRef<jstring> ConvertUTF16ToJavaString(JNIEnv* env,
120 const StringPiece16& str) {
121 return ScopedJavaLocalRef<jstring>(env,
122 ConvertUTF16ToJavaStringImpl(env, str));
123 }
124
125 } // namespace android
126 } // namespace base
127