reflection.cc revision ab9a0dbf3b63d517da5278b8298e6cd316e09f68 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "reflection.h"
18
19#include "class_linker.h"
20#include "common_throws.h"
21#include "dex_file-inl.h"
22#include "jni_internal.h"
23#include "method_helper-inl.h"
24#include "mirror/art_field-inl.h"
25#include "mirror/art_method-inl.h"
26#include "mirror/class-inl.h"
27#include "mirror/class.h"
28#include "mirror/object_array-inl.h"
29#include "mirror/object_array.h"
30#include "nth_caller_visitor.h"
31#include "scoped_thread_state_change.h"
32#include "stack.h"
33#include "well_known_classes.h"
34
35namespace art {
36
37class ArgArray {
38 public:
39  explicit ArgArray(const char* shorty, uint32_t shorty_len)
40      : shorty_(shorty), shorty_len_(shorty_len), num_bytes_(0) {
41    size_t num_slots = shorty_len + 1;  // +1 in case of receiver.
42    if (LIKELY((num_slots * 2) < kSmallArgArraySize)) {
43      // We can trivially use the small arg array.
44      arg_array_ = small_arg_array_;
45    } else {
46      // Analyze shorty to see if we need the large arg array.
47      for (size_t i = 1; i < shorty_len; ++i) {
48        char c = shorty[i];
49        if (c == 'J' || c == 'D') {
50          num_slots++;
51        }
52      }
53      if (num_slots <= kSmallArgArraySize) {
54        arg_array_ = small_arg_array_;
55      } else {
56        large_arg_array_.reset(new uint32_t[num_slots]);
57        arg_array_ = large_arg_array_.get();
58      }
59    }
60  }
61
62  uint32_t* GetArray() {
63    return arg_array_;
64  }
65
66  uint32_t GetNumBytes() {
67    return num_bytes_;
68  }
69
70  void Append(uint32_t value) {
71    arg_array_[num_bytes_ / 4] = value;
72    num_bytes_ += 4;
73  }
74
75  void Append(mirror::Object* obj) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
76    Append(StackReference<mirror::Object>::FromMirrorPtr(obj).AsVRegValue());
77  }
78
79  void AppendWide(uint64_t value) {
80    // For ARM and MIPS portable, align wide values to 8 bytes (ArgArray starts at offset of 4).
81#if defined(ART_USE_PORTABLE_COMPILER) && (defined(__arm__) || defined(__mips__))
82    if (num_bytes_ % 8 == 0) {
83      num_bytes_ += 4;
84    }
85#endif
86    arg_array_[num_bytes_ / 4] = value;
87    arg_array_[(num_bytes_ / 4) + 1] = value >> 32;
88    num_bytes_ += 8;
89  }
90
91  void AppendFloat(float value) {
92    jvalue jv;
93    jv.f = value;
94    Append(jv.i);
95  }
96
97  void AppendDouble(double value) {
98    jvalue jv;
99    jv.d = value;
100    AppendWide(jv.j);
101  }
102
103  void BuildArgArrayFromVarArgs(const ScopedObjectAccessAlreadyRunnable& soa,
104                                mirror::Object* receiver, va_list ap)
105      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
106    // Set receiver if non-null (method is not static)
107    if (receiver != nullptr) {
108      Append(receiver);
109    }
110    for (size_t i = 1; i < shorty_len_; ++i) {
111      switch (shorty_[i]) {
112        case 'Z':
113        case 'B':
114        case 'C':
115        case 'S':
116        case 'I':
117          Append(va_arg(ap, jint));
118          break;
119        case 'F':
120          AppendFloat(va_arg(ap, jdouble));
121          break;
122        case 'L':
123          Append(soa.Decode<mirror::Object*>(va_arg(ap, jobject)));
124          break;
125        case 'D':
126          AppendDouble(va_arg(ap, jdouble));
127          break;
128        case 'J':
129          AppendWide(va_arg(ap, jlong));
130          break;
131#ifndef NDEBUG
132        default:
133          LOG(FATAL) << "Unexpected shorty character: " << shorty_[i];
134#endif
135      }
136    }
137  }
138
139  void BuildArgArrayFromJValues(const ScopedObjectAccessAlreadyRunnable& soa,
140                                mirror::Object* receiver, jvalue* args)
141      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
142    // Set receiver if non-null (method is not static)
143    if (receiver != nullptr) {
144      Append(receiver);
145    }
146    for (size_t i = 1, args_offset = 0; i < shorty_len_; ++i, ++args_offset) {
147      switch (shorty_[i]) {
148        case 'Z':
149          Append(args[args_offset].z);
150          break;
151        case 'B':
152          Append(args[args_offset].b);
153          break;
154        case 'C':
155          Append(args[args_offset].c);
156          break;
157        case 'S':
158          Append(args[args_offset].s);
159          break;
160        case 'I':
161        case 'F':
162          Append(args[args_offset].i);
163          break;
164        case 'L':
165          Append(soa.Decode<mirror::Object*>(args[args_offset].l));
166          break;
167        case 'D':
168        case 'J':
169          AppendWide(args[args_offset].j);
170          break;
171#ifndef NDEBUG
172        default:
173          LOG(FATAL) << "Unexpected shorty character: " << shorty_[i];
174#endif
175      }
176    }
177  }
178
179  void BuildArgArrayFromFrame(ShadowFrame* shadow_frame, uint32_t arg_offset)
180      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
181    // Set receiver if non-null (method is not static)
182    size_t cur_arg = arg_offset;
183    if (!shadow_frame->GetMethod()->IsStatic()) {
184      Append(shadow_frame->GetVReg(cur_arg));
185      cur_arg++;
186    }
187    for (size_t i = 1; i < shorty_len_; ++i) {
188      switch (shorty_[i]) {
189        case 'Z':
190        case 'B':
191        case 'C':
192        case 'S':
193        case 'I':
194        case 'F':
195        case 'L':
196          Append(shadow_frame->GetVReg(cur_arg));
197          cur_arg++;
198          break;
199        case 'D':
200        case 'J':
201          AppendWide(shadow_frame->GetVRegLong(cur_arg));
202          cur_arg++;
203          cur_arg++;
204          break;
205#ifndef NDEBUG
206        default:
207          LOG(FATAL) << "Unexpected shorty character: " << shorty_[i];
208#endif
209      }
210    }
211  }
212
213  static void ThrowIllegalPrimitiveArgumentException(const char* expected,
214                                                     const char* found_descriptor)
215      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
216    ThrowIllegalArgumentException(nullptr,
217        StringPrintf("Invalid primitive conversion from %s to %s", expected,
218                     PrettyDescriptor(found_descriptor).c_str()).c_str());
219  }
220
221  bool BuildArgArrayFromObjectArray(const ScopedObjectAccessAlreadyRunnable& soa,
222                                    mirror::Object* receiver,
223                                    mirror::ObjectArray<mirror::Object>* args, MethodHelper& mh)
224      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
225    const DexFile::TypeList* classes = mh.GetMethod()->GetParameterTypeList();
226    // Set receiver if non-null (method is not static)
227    if (receiver != nullptr) {
228      Append(receiver);
229    }
230    for (size_t i = 1, args_offset = 0; i < shorty_len_; ++i, ++args_offset) {
231      mirror::Object* arg = args->Get(args_offset);
232      if (((shorty_[i] == 'L') && (arg != nullptr)) || ((arg == nullptr && shorty_[i] != 'L'))) {
233        mirror::Class* dst_class =
234            mh.GetClassFromTypeIdx(classes->GetTypeItem(args_offset).type_idx_);
235        if (UNLIKELY(arg == nullptr || !arg->InstanceOf(dst_class))) {
236          ThrowIllegalArgumentException(nullptr,
237              StringPrintf("method %s argument %zd has type %s, got %s",
238                  PrettyMethod(mh.GetMethod(), false).c_str(),
239                  args_offset + 1,  // Humans don't count from 0.
240                  PrettyDescriptor(dst_class).c_str(),
241                  PrettyTypeOf(arg).c_str()).c_str());
242          return false;
243        }
244      }
245
246#define DO_FIRST_ARG(match_descriptor, get_fn, append) { \
247          if (LIKELY(arg != nullptr && arg->GetClass<>()->DescriptorEquals(match_descriptor))) { \
248            mirror::ArtField* primitive_field = arg->GetClass()->GetIFields()->Get(0); \
249            append(primitive_field-> get_fn(arg));
250
251#define DO_ARG(match_descriptor, get_fn, append) \
252          } else if (LIKELY(arg != nullptr && \
253                            arg->GetClass<>()->DescriptorEquals(match_descriptor))) { \
254            mirror::ArtField* primitive_field = arg->GetClass()->GetIFields()->Get(0); \
255            append(primitive_field-> get_fn(arg));
256
257#define DO_FAIL(expected) \
258          } else { \
259            if (arg->GetClass<>()->IsPrimitive()) { \
260              std::string temp; \
261              ThrowIllegalPrimitiveArgumentException(expected, \
262                                                     arg->GetClass<>()->GetDescriptor(&temp)); \
263            } else { \
264              ThrowIllegalArgumentException(nullptr, \
265                  StringPrintf("method %s argument %zd has type %s, got %s", \
266                      PrettyMethod(mh.GetMethod(), false).c_str(), \
267                      args_offset + 1, \
268                      expected, \
269                      PrettyTypeOf(arg).c_str()).c_str()); \
270            } \
271            return false; \
272          } }
273
274      switch (shorty_[i]) {
275        case 'L':
276          Append(arg);
277          break;
278        case 'Z':
279          DO_FIRST_ARG("Ljava/lang/Boolean;", GetBoolean, Append)
280          DO_FAIL("boolean")
281          break;
282        case 'B':
283          DO_FIRST_ARG("Ljava/lang/Byte;", GetByte, Append)
284          DO_FAIL("byte")
285          break;
286        case 'C':
287          DO_FIRST_ARG("Ljava/lang/Character;", GetChar, Append)
288          DO_FAIL("char")
289          break;
290        case 'S':
291          DO_FIRST_ARG("Ljava/lang/Short;", GetShort, Append)
292          DO_ARG("Ljava/lang/Byte;", GetByte, Append)
293          DO_FAIL("short")
294          break;
295        case 'I':
296          DO_FIRST_ARG("Ljava/lang/Integer;", GetInt, Append)
297          DO_ARG("Ljava/lang/Character;", GetChar, Append)
298          DO_ARG("Ljava/lang/Short;", GetShort, Append)
299          DO_ARG("Ljava/lang/Byte;", GetByte, Append)
300          DO_FAIL("int")
301          break;
302        case 'J':
303          DO_FIRST_ARG("Ljava/lang/Long;", GetLong, AppendWide)
304          DO_ARG("Ljava/lang/Integer;", GetInt, AppendWide)
305          DO_ARG("Ljava/lang/Character;", GetChar, AppendWide)
306          DO_ARG("Ljava/lang/Short;", GetShort, AppendWide)
307          DO_ARG("Ljava/lang/Byte;", GetByte, AppendWide)
308          DO_FAIL("long")
309          break;
310        case 'F':
311          DO_FIRST_ARG("Ljava/lang/Float;", GetFloat, AppendFloat)
312          DO_ARG("Ljava/lang/Long;", GetLong, AppendFloat)
313          DO_ARG("Ljava/lang/Integer;", GetInt, AppendFloat)
314          DO_ARG("Ljava/lang/Character;", GetChar, AppendFloat)
315          DO_ARG("Ljava/lang/Short;", GetShort, AppendFloat)
316          DO_ARG("Ljava/lang/Byte;", GetByte, AppendFloat)
317          DO_FAIL("float")
318          break;
319        case 'D':
320          DO_FIRST_ARG("Ljava/lang/Double;", GetDouble, AppendDouble)
321          DO_ARG("Ljava/lang/Float;", GetFloat, AppendDouble)
322          DO_ARG("Ljava/lang/Long;", GetLong, AppendDouble)
323          DO_ARG("Ljava/lang/Integer;", GetInt, AppendDouble)
324          DO_ARG("Ljava/lang/Character;", GetChar, AppendDouble)
325          DO_ARG("Ljava/lang/Short;", GetShort, AppendDouble)
326          DO_ARG("Ljava/lang/Byte;", GetByte, AppendDouble)
327          DO_FAIL("double")
328          break;
329#ifndef NDEBUG
330        default:
331          LOG(FATAL) << "Unexpected shorty character: " << shorty_[i];
332#endif
333      }
334#undef DO_FIRST_ARG
335#undef DO_ARG
336#undef DO_FAIL
337    }
338    return true;
339  }
340
341 private:
342  enum { kSmallArgArraySize = 16 };
343  const char* const shorty_;
344  const uint32_t shorty_len_;
345  uint32_t num_bytes_;
346  uint32_t* arg_array_;
347  uint32_t small_arg_array_[kSmallArgArraySize];
348  std::unique_ptr<uint32_t[]> large_arg_array_;
349};
350
351static void CheckMethodArguments(mirror::ArtMethod* m, uint32_t* args)
352    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
353  const DexFile::TypeList* params = m->GetParameterTypeList();
354  if (params == nullptr) {
355    return;  // No arguments so nothing to check.
356  }
357  uint32_t offset = 0;
358  uint32_t num_params = params->Size();
359  size_t error_count = 0;
360  if (!m->IsStatic()) {
361    offset = 1;
362  }
363  // TODO: If args contain object references, it may cause problems
364  Thread* self = Thread::Current();
365  StackHandleScope<1> hs(self);
366  Handle<mirror::ArtMethod> h_m(hs.NewHandle(m));
367  MethodHelper mh(h_m);
368  for (uint32_t i = 0; i < num_params; i++) {
369    uint16_t type_idx = params->GetTypeItem(i).type_idx_;
370    mirror::Class* param_type = mh.GetClassFromTypeIdx(type_idx);
371    if (param_type == nullptr) {
372      CHECK(self->IsExceptionPending());
373      LOG(ERROR) << "Internal error: unresolvable type for argument type in JNI invoke: "
374          << h_m->GetTypeDescriptorFromTypeIdx(type_idx) << "\n"
375          << self->GetException(nullptr)->Dump();
376      self->ClearException();
377      ++error_count;
378    } else if (!param_type->IsPrimitive()) {
379      // TODO: check primitives are in range.
380      // TODO: There is a compaction bug here since GetClassFromTypeIdx can cause thread suspension,
381      // this is a hard to fix problem since the args can contain Object*, we need to save and
382      // restore them by using a visitor similar to the ones used in the trampoline entrypoints.
383      mirror::Object* argument = reinterpret_cast<mirror::Object*>(args[i + offset]);
384      if (argument != nullptr && !argument->InstanceOf(param_type)) {
385        LOG(ERROR) << "JNI ERROR (app bug): attempt to pass an instance of "
386                   << PrettyTypeOf(argument) << " as argument " << (i + 1)
387                   << " to " << PrettyMethod(h_m.Get());
388        ++error_count;
389      }
390    } else if (param_type->IsPrimitiveLong() || param_type->IsPrimitiveDouble()) {
391      offset++;
392    }
393  }
394  if (error_count > 0) {
395    // TODO: pass the JNI function name (such as "CallVoidMethodV") through so we can call JniAbort
396    // with an argument.
397    JniAbortF(nullptr, "bad arguments passed to %s (see above for details)",
398              PrettyMethod(h_m.Get()).c_str());
399  }
400}
401
402static mirror::ArtMethod* FindVirtualMethod(mirror::Object* receiver,
403                                            mirror::ArtMethod* method)
404    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
405  return receiver->GetClass()->FindVirtualMethodForVirtualOrInterface(method);
406}
407
408
409static void InvokeWithArgArray(const ScopedObjectAccessAlreadyRunnable& soa,
410                               mirror::ArtMethod* method, ArgArray* arg_array, JValue* result,
411                               const char* shorty)
412    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
413  uint32_t* args = arg_array->GetArray();
414  if (UNLIKELY(soa.Env()->check_jni)) {
415    CheckMethodArguments(method, args);
416  }
417  method->Invoke(soa.Self(), args, arg_array->GetNumBytes(), result, shorty);
418}
419
420JValue InvokeWithVarArgs(const ScopedObjectAccessAlreadyRunnable& soa, jobject obj, jmethodID mid,
421                         va_list args)
422    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
423  mirror::ArtMethod* method = soa.DecodeMethod(mid);
424  mirror::Object* receiver = method->IsStatic() ? nullptr : soa.Decode<mirror::Object*>(obj);
425  uint32_t shorty_len = 0;
426  const char* shorty = method->GetShorty(&shorty_len);
427  JValue result;
428  ArgArray arg_array(shorty, shorty_len);
429  arg_array.BuildArgArrayFromVarArgs(soa, receiver, args);
430  InvokeWithArgArray(soa, method, &arg_array, &result, shorty);
431  return result;
432}
433
434JValue InvokeWithJValues(const ScopedObjectAccessAlreadyRunnable& soa, mirror::Object* receiver,
435                         jmethodID mid, jvalue* args) {
436  mirror::ArtMethod* method = soa.DecodeMethod(mid);
437  uint32_t shorty_len = 0;
438  const char* shorty = method->GetShorty(&shorty_len);
439  JValue result;
440  ArgArray arg_array(shorty, shorty_len);
441  arg_array.BuildArgArrayFromJValues(soa, receiver, args);
442  InvokeWithArgArray(soa, method, &arg_array, &result, shorty);
443  return result;
444}
445
446JValue InvokeVirtualOrInterfaceWithJValues(const ScopedObjectAccessAlreadyRunnable& soa,
447                                           mirror::Object* receiver, jmethodID mid, jvalue* args) {
448  mirror::ArtMethod* method = FindVirtualMethod(receiver, soa.DecodeMethod(mid));
449  uint32_t shorty_len = 0;
450  const char* shorty = method->GetShorty(&shorty_len);
451  JValue result;
452  ArgArray arg_array(shorty, shorty_len);
453  arg_array.BuildArgArrayFromJValues(soa, receiver, args);
454  InvokeWithArgArray(soa, method, &arg_array, &result, shorty);
455  return result;
456}
457
458JValue InvokeVirtualOrInterfaceWithVarArgs(const ScopedObjectAccessAlreadyRunnable& soa,
459                                           jobject obj, jmethodID mid, va_list args) {
460  mirror::Object* receiver = soa.Decode<mirror::Object*>(obj);
461  mirror::ArtMethod* method = FindVirtualMethod(receiver, soa.DecodeMethod(mid));
462  uint32_t shorty_len = 0;
463  const char* shorty = method->GetShorty(&shorty_len);
464  JValue result;
465  ArgArray arg_array(shorty, shorty_len);
466  arg_array.BuildArgArrayFromVarArgs(soa, receiver, args);
467  InvokeWithArgArray(soa, method, &arg_array, &result, shorty);
468  return result;
469}
470
471void InvokeWithShadowFrame(Thread* self, ShadowFrame* shadow_frame, uint16_t arg_offset,
472                           MethodHelper& mh, JValue* result) {
473  ArgArray arg_array(mh.GetShorty(), mh.GetShortyLength());
474  arg_array.BuildArgArrayFromFrame(shadow_frame, arg_offset);
475  shadow_frame->GetMethod()->Invoke(self, arg_array.GetArray(), arg_array.GetNumBytes(), result,
476                                    mh.GetShorty());
477}
478
479jobject InvokeMethod(const ScopedObjectAccessAlreadyRunnable& soa, jobject javaMethod,
480                     jobject javaReceiver, jobject javaArgs, bool accessible) {
481  mirror::ArtMethod* m = mirror::ArtMethod::FromReflectedMethod(soa, javaMethod);
482
483  mirror::Class* declaring_class = m->GetDeclaringClass();
484  if (UNLIKELY(!declaring_class->IsInitialized())) {
485    StackHandleScope<1> hs(soa.Self());
486    Handle<mirror::Class> h_class(hs.NewHandle(declaring_class));
487    if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(h_class, true, true)) {
488      return nullptr;
489    }
490    declaring_class = h_class.Get();
491  }
492
493  mirror::Object* receiver = nullptr;
494  if (!m->IsStatic()) {
495    // Check that the receiver is non-null and an instance of the field's declaring class.
496    receiver = soa.Decode<mirror::Object*>(javaReceiver);
497    if (!VerifyObjectIsClass(receiver, declaring_class)) {
498      return NULL;
499    }
500
501    // Find the actual implementation of the virtual method.
502    m = receiver->GetClass()->FindVirtualMethodForVirtualOrInterface(m);
503  }
504
505  // Get our arrays of arguments and their types, and check they're the same size.
506  mirror::ObjectArray<mirror::Object>* objects =
507      soa.Decode<mirror::ObjectArray<mirror::Object>*>(javaArgs);
508  const DexFile::TypeList* classes = m->GetParameterTypeList();
509  uint32_t classes_size = (classes == nullptr) ? 0 : classes->Size();
510  uint32_t arg_count = (objects != nullptr) ? objects->GetLength() : 0;
511  if (arg_count != classes_size) {
512    ThrowIllegalArgumentException(NULL,
513                                  StringPrintf("Wrong number of arguments; expected %d, got %d",
514                                               classes_size, arg_count).c_str());
515    return NULL;
516  }
517
518  // If method is not set to be accessible, verify it can be accessed by the caller.
519  if (!accessible && !VerifyAccess(receiver, declaring_class, m->GetAccessFlags())) {
520    ThrowIllegalAccessException(nullptr, StringPrintf("Cannot access method: %s",
521                                                      PrettyMethod(m).c_str()).c_str());
522    return nullptr;
523  }
524
525  // Invoke the method.
526  JValue result;
527  uint32_t shorty_len = 0;
528  const char* shorty = m->GetShorty(&shorty_len);
529  ArgArray arg_array(shorty, shorty_len);
530  StackHandleScope<1> hs(soa.Self());
531  MethodHelper mh(hs.NewHandle(m));
532  if (!arg_array.BuildArgArrayFromObjectArray(soa, receiver, objects, mh)) {
533    CHECK(soa.Self()->IsExceptionPending());
534    return nullptr;
535  }
536
537  InvokeWithArgArray(soa, m, &arg_array, &result, shorty);
538
539  // Wrap any exception with "Ljava/lang/reflect/InvocationTargetException;" and return early.
540  if (soa.Self()->IsExceptionPending()) {
541    jthrowable th = soa.Env()->ExceptionOccurred();
542    soa.Env()->ExceptionClear();
543    jclass exception_class = soa.Env()->FindClass("java/lang/reflect/InvocationTargetException");
544    jmethodID mid = soa.Env()->GetMethodID(exception_class, "<init>", "(Ljava/lang/Throwable;)V");
545    jobject exception_instance = soa.Env()->NewObject(exception_class, mid, th);
546    soa.Env()->Throw(reinterpret_cast<jthrowable>(exception_instance));
547    return NULL;
548  }
549
550  // Box if necessary and return.
551  return soa.AddLocalReference<jobject>(BoxPrimitive(mh.GetReturnType()->GetPrimitiveType(),
552                                                     result));
553}
554
555bool VerifyObjectIsClass(mirror::Object* o, mirror::Class* c) {
556  if (o == NULL) {
557    ThrowNullPointerException(NULL, "null receiver");
558    return false;
559  } else if (!o->InstanceOf(c)) {
560    std::string expected_class_name(PrettyDescriptor(c));
561    std::string actual_class_name(PrettyTypeOf(o));
562    ThrowIllegalArgumentException(NULL,
563                                  StringPrintf("Expected receiver of type %s, but got %s",
564                                               expected_class_name.c_str(),
565                                               actual_class_name.c_str()).c_str());
566    return false;
567  }
568  return true;
569}
570
571static std::string PrettyDescriptor(Primitive::Type type) {
572  return PrettyDescriptor(Primitive::Descriptor(type));
573}
574
575bool ConvertPrimitiveValue(const ThrowLocation* throw_location, bool unbox_for_result,
576                           Primitive::Type srcType, Primitive::Type dstType,
577                           const JValue& src, JValue* dst) {
578  DCHECK(srcType != Primitive::kPrimNot && dstType != Primitive::kPrimNot);
579  if (LIKELY(srcType == dstType)) {
580    dst->SetJ(src.GetJ());
581    return true;
582  }
583  switch (dstType) {
584  case Primitive::kPrimBoolean:  // Fall-through.
585  case Primitive::kPrimChar:  // Fall-through.
586  case Primitive::kPrimByte:
587    // Only expect assignment with source and destination of identical type.
588    break;
589  case Primitive::kPrimShort:
590    if (srcType == Primitive::kPrimByte) {
591      dst->SetS(src.GetI());
592      return true;
593    }
594    break;
595  case Primitive::kPrimInt:
596    if (srcType == Primitive::kPrimByte || srcType == Primitive::kPrimChar ||
597        srcType == Primitive::kPrimShort) {
598      dst->SetI(src.GetI());
599      return true;
600    }
601    break;
602  case Primitive::kPrimLong:
603    if (srcType == Primitive::kPrimByte || srcType == Primitive::kPrimChar ||
604        srcType == Primitive::kPrimShort || srcType == Primitive::kPrimInt) {
605      dst->SetJ(src.GetI());
606      return true;
607    }
608    break;
609  case Primitive::kPrimFloat:
610    if (srcType == Primitive::kPrimByte || srcType == Primitive::kPrimChar ||
611        srcType == Primitive::kPrimShort || srcType == Primitive::kPrimInt) {
612      dst->SetF(src.GetI());
613      return true;
614    } else if (srcType == Primitive::kPrimLong) {
615      dst->SetF(src.GetJ());
616      return true;
617    }
618    break;
619  case Primitive::kPrimDouble:
620    if (srcType == Primitive::kPrimByte || srcType == Primitive::kPrimChar ||
621        srcType == Primitive::kPrimShort || srcType == Primitive::kPrimInt) {
622      dst->SetD(src.GetI());
623      return true;
624    } else if (srcType == Primitive::kPrimLong) {
625      dst->SetD(src.GetJ());
626      return true;
627    } else if (srcType == Primitive::kPrimFloat) {
628      dst->SetD(src.GetF());
629      return true;
630    }
631    break;
632  default:
633    break;
634  }
635  if (!unbox_for_result) {
636    ThrowIllegalArgumentException(throw_location,
637                                  StringPrintf("Invalid primitive conversion from %s to %s",
638                                               PrettyDescriptor(srcType).c_str(),
639                                               PrettyDescriptor(dstType).c_str()).c_str());
640  } else {
641    ThrowClassCastException(throw_location,
642                            StringPrintf("Couldn't convert result of type %s to %s",
643                                         PrettyDescriptor(srcType).c_str(),
644                                         PrettyDescriptor(dstType).c_str()).c_str());
645  }
646  return false;
647}
648
649mirror::Object* BoxPrimitive(Primitive::Type src_class, const JValue& value) {
650  if (src_class == Primitive::kPrimNot) {
651    return value.GetL();
652  }
653  if (src_class == Primitive::kPrimVoid) {
654    // There's no such thing as a void field, and void methods invoked via reflection return null.
655    return nullptr;
656  }
657
658  jmethodID m = nullptr;
659  const char* shorty;
660  switch (src_class) {
661  case Primitive::kPrimBoolean:
662    m = WellKnownClasses::java_lang_Boolean_valueOf;
663    shorty = "LZ";
664    break;
665  case Primitive::kPrimByte:
666    m = WellKnownClasses::java_lang_Byte_valueOf;
667    shorty = "LB";
668    break;
669  case Primitive::kPrimChar:
670    m = WellKnownClasses::java_lang_Character_valueOf;
671    shorty = "LC";
672    break;
673  case Primitive::kPrimDouble:
674    m = WellKnownClasses::java_lang_Double_valueOf;
675    shorty = "LD";
676    break;
677  case Primitive::kPrimFloat:
678    m = WellKnownClasses::java_lang_Float_valueOf;
679    shorty = "LF";
680    break;
681  case Primitive::kPrimInt:
682    m = WellKnownClasses::java_lang_Integer_valueOf;
683    shorty = "LI";
684    break;
685  case Primitive::kPrimLong:
686    m = WellKnownClasses::java_lang_Long_valueOf;
687    shorty = "LJ";
688    break;
689  case Primitive::kPrimShort:
690    m = WellKnownClasses::java_lang_Short_valueOf;
691    shorty = "LS";
692    break;
693  default:
694    LOG(FATAL) << static_cast<int>(src_class);
695    shorty = nullptr;
696  }
697
698  ScopedObjectAccessUnchecked soa(Thread::Current());
699  DCHECK_EQ(soa.Self()->GetState(), kRunnable);
700
701  ArgArray arg_array(shorty, 2);
702  JValue result;
703  if (src_class == Primitive::kPrimDouble || src_class == Primitive::kPrimLong) {
704    arg_array.AppendWide(value.GetJ());
705  } else {
706    arg_array.Append(value.GetI());
707  }
708
709  soa.DecodeMethod(m)->Invoke(soa.Self(), arg_array.GetArray(), arg_array.GetNumBytes(),
710                              &result, shorty);
711  return result.GetL();
712}
713
714static std::string UnboxingFailureKind(mirror::ArtField* f)
715    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
716  if (f != nullptr) {
717    return "field " + PrettyField(f, false);
718  }
719  return "result";
720}
721
722static bool UnboxPrimitive(const ThrowLocation* throw_location, mirror::Object* o,
723                           mirror::Class* dst_class, mirror::ArtField* f,
724                           JValue* unboxed_value)
725    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
726  bool unbox_for_result = (f == nullptr);
727  if (!dst_class->IsPrimitive()) {
728    if (UNLIKELY(o != nullptr && !o->InstanceOf(dst_class))) {
729      if (!unbox_for_result) {
730        ThrowIllegalArgumentException(throw_location,
731                                      StringPrintf("%s has type %s, got %s",
732                                                   UnboxingFailureKind(f).c_str(),
733                                                   PrettyDescriptor(dst_class).c_str(),
734                                                   PrettyTypeOf(o).c_str()).c_str());
735      } else {
736        ThrowClassCastException(throw_location,
737                                StringPrintf("Couldn't convert result of type %s to %s",
738                                             PrettyTypeOf(o).c_str(),
739                                             PrettyDescriptor(dst_class).c_str()).c_str());
740      }
741      return false;
742    }
743    unboxed_value->SetL(o);
744    return true;
745  }
746  if (UNLIKELY(dst_class->GetPrimitiveType() == Primitive::kPrimVoid)) {
747    ThrowIllegalArgumentException(throw_location,
748                                  StringPrintf("Can't unbox %s to void",
749                                               UnboxingFailureKind(f).c_str()).c_str());
750    return false;
751  }
752  if (UNLIKELY(o == nullptr)) {
753    if (!unbox_for_result) {
754      ThrowIllegalArgumentException(throw_location,
755                                    StringPrintf("%s has type %s, got null",
756                                                 UnboxingFailureKind(f).c_str(),
757                                                 PrettyDescriptor(dst_class).c_str()).c_str());
758    } else {
759      ThrowNullPointerException(throw_location,
760                                StringPrintf("Expected to unbox a '%s' primitive type but was returned null",
761                                             PrettyDescriptor(dst_class).c_str()).c_str());
762    }
763    return false;
764  }
765
766  JValue boxed_value;
767  mirror::Class* klass = o->GetClass();
768  mirror::Class* src_class = nullptr;
769  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
770  mirror::ArtField* primitive_field = o->GetClass()->GetIFields()->Get(0);
771  if (klass->DescriptorEquals("Ljava/lang/Boolean;")) {
772    src_class = class_linker->FindPrimitiveClass('Z');
773    boxed_value.SetZ(primitive_field->GetBoolean(o));
774  } else if (klass->DescriptorEquals("Ljava/lang/Byte;")) {
775    src_class = class_linker->FindPrimitiveClass('B');
776    boxed_value.SetB(primitive_field->GetByte(o));
777  } else if (klass->DescriptorEquals("Ljava/lang/Character;")) {
778    src_class = class_linker->FindPrimitiveClass('C');
779    boxed_value.SetC(primitive_field->GetChar(o));
780  } else if (klass->DescriptorEquals("Ljava/lang/Float;")) {
781    src_class = class_linker->FindPrimitiveClass('F');
782    boxed_value.SetF(primitive_field->GetFloat(o));
783  } else if (klass->DescriptorEquals("Ljava/lang/Double;")) {
784    src_class = class_linker->FindPrimitiveClass('D');
785    boxed_value.SetD(primitive_field->GetDouble(o));
786  } else if (klass->DescriptorEquals("Ljava/lang/Integer;")) {
787    src_class = class_linker->FindPrimitiveClass('I');
788    boxed_value.SetI(primitive_field->GetInt(o));
789  } else if (klass->DescriptorEquals("Ljava/lang/Long;")) {
790    src_class = class_linker->FindPrimitiveClass('J');
791    boxed_value.SetJ(primitive_field->GetLong(o));
792  } else if (klass->DescriptorEquals("Ljava/lang/Short;")) {
793    src_class = class_linker->FindPrimitiveClass('S');
794    boxed_value.SetS(primitive_field->GetShort(o));
795  } else {
796    std::string temp;
797    ThrowIllegalArgumentException(throw_location,
798        StringPrintf("%s has type %s, got %s", UnboxingFailureKind(f).c_str(),
799            PrettyDescriptor(dst_class).c_str(),
800            PrettyDescriptor(o->GetClass()->GetDescriptor(&temp)).c_str()).c_str());
801    return false;
802  }
803
804  return ConvertPrimitiveValue(throw_location, unbox_for_result,
805                               src_class->GetPrimitiveType(), dst_class->GetPrimitiveType(),
806                               boxed_value, unboxed_value);
807}
808
809bool UnboxPrimitiveForField(mirror::Object* o, mirror::Class* dst_class, mirror::ArtField* f,
810                            JValue* unboxed_value) {
811  DCHECK(f != nullptr);
812  return UnboxPrimitive(nullptr, o, dst_class, f, unboxed_value);
813}
814
815bool UnboxPrimitiveForResult(const ThrowLocation& throw_location, mirror::Object* o,
816                             mirror::Class* dst_class, JValue* unboxed_value) {
817  return UnboxPrimitive(&throw_location, o, dst_class, nullptr, unboxed_value);
818}
819
820bool VerifyAccess(mirror::Object* obj, mirror::Class* declaring_class, uint32_t access_flags) {
821  NthCallerVisitor visitor(Thread::Current(), 2);
822  visitor.WalkStack();
823  if (UNLIKELY(visitor.caller == nullptr)) {
824    // The caller is an attached native thread.
825    return (access_flags & kAccPublic) != 0;
826  }
827  mirror::Class* caller_class = visitor.caller->GetDeclaringClass();
828
829  if (((access_flags & kAccPublic) != 0) || (caller_class == declaring_class)) {
830    return true;
831  }
832  if ((access_flags & kAccPrivate) != 0) {
833    return false;
834  }
835  if ((access_flags & kAccProtected) != 0) {
836    if (obj != nullptr && !obj->InstanceOf(caller_class) &&
837        !declaring_class->IsInSamePackage(caller_class)) {
838      return false;
839    } else if (declaring_class->IsAssignableFrom(caller_class)) {
840      return true;
841    }
842  }
843  if (!declaring_class->IsInSamePackage(caller_class)) {
844    return false;
845  }
846  return true;
847}
848
849}  // namespace art
850