1 /*
2 * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 #include "jdk_internal_foreign_abi_fallback_LibFallback.h"
27
28 #include <ffi.h>
29
30 #include <errno.h>
31 #include <stdint.h>
32 #include <wchar.h>
33 #ifdef _WIN64
34 #include <Windows.h>
35 #include <Winsock2.h>
36 #endif
37
38 #include "jlong.h"
39
40 static JavaVM* VM;
41 static jclass LibFallback_class;
42 static jmethodID LibFallback_doUpcall_ID;
43 static const char* LibFallback_doUpcall_sig = "(JJLjava/lang/invoke/MethodHandle;)V";
44
45 JNIEXPORT void JNICALL
46 Java_jdk_internal_foreign_abi_fallback_LibFallback_init(JNIEnv* env, jclass cls) {
47 (*env)->GetJavaVM(env, &VM);
48 LibFallback_class = (*env)->FindClass(env, "jdk/internal/foreign/abi/fallback/LibFallback");
49 LibFallback_doUpcall_ID = (*env)->GetStaticMethodID(env,
50 LibFallback_class, "doUpcall", LibFallback_doUpcall_sig);
51 }
52
53 JNIEXPORT jlong JNICALL
54 Java_jdk_internal_foreign_abi_fallback_LibFallback_sizeofCif(JNIEnv* env, jclass cls) {
55 return sizeof(ffi_cif);
56 }
57
58 JNIEXPORT jint JNICALL
59 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1prep_1cif(JNIEnv* env, jclass cls, jlong cif, jint abi, jint nargs, jlong rtype, jlong atypes) {
60 return ffi_prep_cif(jlong_to_ptr(cif), (ffi_abi) abi, (unsigned int) nargs, jlong_to_ptr(rtype), jlong_to_ptr(atypes));
61 }
62 JNIEXPORT jint JNICALL
63 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1prep_1cif_1var(JNIEnv* env, jclass cls, jlong cif, jint abi, jint nfixedargs, jint ntotalargs, jlong rtype, jlong atypes) {
64 return ffi_prep_cif_var(jlong_to_ptr(cif), (ffi_abi) abi, (unsigned int) nfixedargs, (unsigned int) ntotalargs, jlong_to_ptr(rtype), jlong_to_ptr(atypes));
65 }
66 JNIEXPORT jint JNICALL
67 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1get_1struct_1offsets(JNIEnv* env, jclass cls, jint abi, jlong type, jlong offsets) {
68 return ffi_get_struct_offsets((ffi_abi) abi, jlong_to_ptr(type), jlong_to_ptr(offsets));
69 }
70
71 static void do_capture_state(int32_t* value_ptr, int captured_state_mask) {
72 // keep in synch with jdk.internal.foreign.abi.CapturableState
73 enum PreservableValues {
74 NONE = 0,
75 GET_LAST_ERROR = 1,
76 WSA_GET_LAST_ERROR = 1 << 1,
77 ERRNO = 1 << 2
78 };
79 #ifdef _WIN64
80 if (captured_state_mask & GET_LAST_ERROR) {
81 *value_ptr = GetLastError();
82 }
83 value_ptr++;
84 if (captured_state_mask & WSA_GET_LAST_ERROR) {
85 *value_ptr = WSAGetLastError();
86 }
87 value_ptr++;
88 #endif
89 if (captured_state_mask & ERRNO) {
90 *value_ptr = errno;
91 }
92 }
93
94 JNIEXPORT void JNICALL
95 Java_jdk_internal_foreign_abi_fallback_LibFallback_doDowncall(JNIEnv* env, jclass cls, jlong cif, jlong fn, jlong rvalue, jlong avalues, jlong jcaptured_state, jint captured_state_mask) {
96 ffi_call(jlong_to_ptr(cif), jlong_to_ptr(fn), jlong_to_ptr(rvalue), jlong_to_ptr(avalues));
97
98 if (captured_state_mask != 0) {
99 int32_t* captured_state = jlong_to_ptr(jcaptured_state);
100 do_capture_state(captured_state, captured_state_mask);
101 }
102 }
103
104 static void do_upcall(ffi_cif* cif, void* ret, void** args, void* user_data) {
105 // attach thread
106 JNIEnv* env;
107 jint result = (*VM)->AttachCurrentThreadAsDaemon(VM, (void**) &env, NULL);
108
109 // call into doUpcall in LibFallback
110 jobject upcall_data = (jobject) user_data;
111 (*env)->CallStaticVoidMethod(env, LibFallback_class, LibFallback_doUpcall_ID,
112 ptr_to_jlong(ret), ptr_to_jlong(args), upcall_data);
113
114 // always detach for now
115 (*VM)->DetachCurrentThread(VM);
116 }
117
118 static void free_closure(JNIEnv* env, void* closure, jobject upcall_data) {
119 ffi_closure_free(closure);
120 (*env)->DeleteGlobalRef(env, upcall_data);
121 }
122
123 JNIEXPORT jint JNICALL
124 Java_jdk_internal_foreign_abi_fallback_LibFallback_createClosure(JNIEnv* env, jclass cls, jlong cif, jobject upcall_data, jlongArray jptrs) {
125 void* code;
126 void* closure = ffi_closure_alloc(sizeof(ffi_closure), &code);
127
128 jobject global_upcall_data = (*env)->NewGlobalRef(env, upcall_data);
129
130 ffi_status status = ffi_prep_closure_loc(closure, jlong_to_ptr(cif), &do_upcall, (void*) global_upcall_data, code);
131
132 if (status != FFI_OK) {
133 free_closure(env,closure, global_upcall_data);
134 return status;
135 }
136
137 jlong* ptrs = (*env)->GetLongArrayElements(env, jptrs, NULL);
138 ptrs[0] = ptr_to_jlong(closure);
139 ptrs[1] = ptr_to_jlong(code);
140 ptrs[2] = ptr_to_jlong(global_upcall_data);
141 (*env)->ReleaseLongArrayElements(env, jptrs, ptrs, JNI_COMMIT);
142
143 return status;
144 }
145
146 JNIEXPORT void JNICALL
147 Java_jdk_internal_foreign_abi_fallback_LibFallback_freeClosure(JNIEnv* env, jclass cls, jlong closure, jlong upcall_data) {
148 free_closure(env, jlong_to_ptr(closure), jlong_to_ptr(upcall_data));
149 }
150
151 JNIEXPORT jint JNICALL
152 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1default_1abi(JNIEnv* env, jclass cls) {
153 return (jint) FFI_DEFAULT_ABI;
154 }
155
156 JNIEXPORT jshort JNICALL
157 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1struct(JNIEnv* env, jclass cls) {
158 return (jshort) FFI_TYPE_STRUCT;
159 }
160
161 JNIEXPORT jlong JNICALL
162 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1void(JNIEnv* env, jclass cls) {
163 return ptr_to_jlong(&ffi_type_void);
164 }
165
166 JNIEXPORT jlong JNICALL
167 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1uint8(JNIEnv* env, jclass cls) {
168 return ptr_to_jlong(&ffi_type_uint8);
169 }
170 JNIEXPORT jlong JNICALL
171 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1sint8(JNIEnv* env, jclass cls) {
172 return ptr_to_jlong(&ffi_type_sint8);
173 }
174 JNIEXPORT jlong JNICALL
175 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1uint16(JNIEnv* env, jclass cls) {
176 return ptr_to_jlong(&ffi_type_uint16);
177 }
178 JNIEXPORT jlong JNICALL
179 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1sint16(JNIEnv* env, jclass cls) {
180 return ptr_to_jlong(&ffi_type_sint16);
181 }
182 JNIEXPORT jlong JNICALL
183 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1uint32(JNIEnv* env, jclass cls) {
184 return ptr_to_jlong(&ffi_type_uint32);
185 }
186 JNIEXPORT jlong JNICALL
187 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1sint32(JNIEnv* env, jclass cls) {
188 return ptr_to_jlong(&ffi_type_sint32);
189 }
190 JNIEXPORT jlong JNICALL
191 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1uint64(JNIEnv* env, jclass cls) {
192 return ptr_to_jlong(&ffi_type_uint64);
193 }
194 JNIEXPORT jlong JNICALL
195 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1sint64(JNIEnv* env, jclass cls) {
196 return ptr_to_jlong(&ffi_type_sint64);
197 }
198 JNIEXPORT jlong JNICALL
199 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1float(JNIEnv* env, jclass cls) {
200 return ptr_to_jlong(&ffi_type_float);
201 }
202 JNIEXPORT jlong JNICALL
203 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1double(JNIEnv* env, jclass cls) {
204 return ptr_to_jlong(&ffi_type_double);
205 }
206 JNIEXPORT jlong JNICALL
207 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1type_1pointer(JNIEnv* env, jclass cls) {
208 return ptr_to_jlong(&ffi_type_pointer);
209 }
210
211 JNIEXPORT jint JNICALL
212 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1sizeof_1short(JNIEnv* env, jclass cls) {
213 return sizeof(short);
214 }
215
216 JNIEXPORT jint JNICALL
217 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1sizeof_1int(JNIEnv* env, jclass cls) {
218 return sizeof(int);
219 }
220
221 JNIEXPORT jint JNICALL
222 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1sizeof_1long(JNIEnv* env, jclass cls) {
223 return sizeof(long);
224 }
225
226 JNIEXPORT jint JNICALL
227 Java_jdk_internal_foreign_abi_fallback_LibFallback_ffi_1sizeof_1wchar(JNIEnv* env, jclass cls) {
228 return sizeof(wchar_t);
229 }