dalvik/vm/JniInternal.h

   1 /*
   2  * Copyright (C) 2008 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  * JNI innards, common to the regular and "checked" interfaces.
  18  */
  19 #ifndef DALVIK_JNIINTERNAL_H_
  20 #define DALVIK_JNIINTERNAL_H_
  21
  22 #include "jni.h"
  23
  24 /* system init/shutdown */
  25 bool dvmJniStartup(void);
  26 void dvmJniShutdown(void);
  27
  28 /*
  29  * Our data structures for JNIEnv and JavaVM.
  30  *
  31  * Native code thinks it has a pointer to a pointer.  We know better.
  32  */
  33 struct JavaVMExt;
  34
  35 struct JNIEnvExt {
  36     const struct JNINativeInterface* funcTable;     /* must be first */
  37
  38     const struct JNINativeInterface* baseFuncTable;
  39
  40     u4      envThreadId;
  41     Thread* self;
  42
  43     /* if nonzero, we are in a "critical" JNI call */
  44     int     critical;
  45
  46     struct JNIEnvExt* prev;
  47     struct JNIEnvExt* next;
  48 };
  49
  50 struct JavaVMExt {
  51     const struct JNIInvokeInterface* funcTable;     /* must be first */
  52
  53     const struct JNIInvokeInterface* baseFuncTable;
  54
  55     /* head of list of JNIEnvs associated with this VM */
  56     JNIEnvExt*      envList;
  57     pthread_mutex_t envListLock;
  58 };
  59
  60 /*
  61  * Native function return type; used by dvmPlatformInvoke().
  62  *
  63  * This is part of Method.jniArgInfo, and must fit in 3 bits.
  64  * Note: Assembly code in arch/<arch>/Call<arch>.S relies on
  65  * the enum values defined here.
  66  */
  67 enum DalvikJniReturnType {
  68     DALVIK_JNI_RETURN_VOID = 0,     /* must be zero */
  69     DALVIK_JNI_RETURN_FLOAT = 1,
  70     DALVIK_JNI_RETURN_DOUBLE = 2,
  71     DALVIK_JNI_RETURN_S8 = 3,
  72     DALVIK_JNI_RETURN_S4 = 4,
  73     DALVIK_JNI_RETURN_S2 = 5,
  74     DALVIK_JNI_RETURN_U2 = 6,
  75     DALVIK_JNI_RETURN_S1 = 7
  76 };
  77
  78 #define DALVIK_JNI_NO_ARG_INFO  0x80000000
  79 #define DALVIK_JNI_RETURN_MASK  0x70000000
  80 #define DALVIK_JNI_RETURN_SHIFT 28
  81 #define DALVIK_JNI_COUNT_MASK   0x0f000000
  82 #define DALVIK_JNI_COUNT_SHIFT  24
  83
  84
  85 /*
  86  * Pop the JNI local stack when we return from a native method.  "saveArea"
  87  * points to the StackSaveArea for the method we're leaving.
  88  *
  89  * (This may be implemented directly in assembly in mterp, so changes here
  90  * may only affect the portable interpreter.)
  91  */
  92 INLINE void dvmPopJniLocals(Thread* self, StackSaveArea* saveArea)
  93 {
  94     self->jniLocalRefTable.segmentState.all = saveArea->xtra.localRefCookie;
  95 }
  96
  97 /*
  98  * Set the envThreadId field.
  99  */
 100 INLINE void dvmSetJniEnvThreadId(JNIEnv* pEnv, Thread* self)
 101 {
 102     ((JNIEnvExt*)pEnv)->envThreadId = self->threadId;
 103     ((JNIEnvExt*)pEnv)->self = self;
 104 }
 105
 106 void dvmCallJNIMethod(const u4* args, JValue* pResult,
 107     const Method* method, Thread* self);
 108 void dvmCheckCallJNIMethod(const u4* args, JValue* pResult,
 109     const Method* method, Thread* self);
 110
 111 /*
 112  * Configure "method" to use the JNI bridge to call "func".
 113  */
 114 void dvmUseJNIBridge(Method* method, void* func);
 115
 116
 117 /*
 118  * Enable the "checked" versions.
 119  */
 120 void dvmUseCheckedJniEnv(JNIEnvExt* pEnv);
 121 void dvmUseCheckedJniVm(JavaVMExt* pVm);
 122 void dvmLateEnableCheckedJni(void);
 123
 124 /*
 125  * Decode a local, global, or weak-global reference.
 126  */
 127 Object* dvmDecodeIndirectRef(Thread* self, jobject jobj);
 128
 129 /*
 130  * Verify that a reference passed in from native code is valid.  Returns
 131  * an indication of local/global/invalid.
 132  */
 133 jobjectRefType dvmGetJNIRefType(Thread* self, jobject jobj);
 134
 135 /*
 136  * Get the last method called on the interp stack.  This is the method
 137  * "responsible" for calling into JNI.
 138  */
 139 const Method* dvmGetCurrentJNIMethod(void);
 140
 141 /*
 142  * Create/destroy a JNIEnv for the current thread.
 143  */
 144 JNIEnv* dvmCreateJNIEnv(Thread* self);
 145 void dvmDestroyJNIEnv(JNIEnv* env);
 146
 147 /*
 148  * Find the JNIEnv associated with the current thread.
 149  */
 150 JNIEnvExt* dvmGetJNIEnvForThread(void);
 151
 152 /*
 153  * Release all MonitorEnter-acquired locks that are still held.  Called at
 154  * DetachCurrentThread time.
 155  */
 156 void dvmReleaseJniMonitors(Thread* self);
 157
 158 /*
 159  * Dump the contents of the JNI reference tables to the log file.
 160  *
 161  * The local ref tables associated with other threads are not included.
 162  */
 163 void dvmDumpJniReferenceTables(void);
 164
 165 #endif  // DALVIK_JNIINTERNAL_H_