]> git.bitcoin.ninja Git - ldk-java/blob - java_strings.py
[TS] Be more aggressive with type checks
[ldk-java] / java_strings.py
1 from bindingstypes import *
2 from enum import Enum
3 import sys
4
5 class Target(Enum):
6     JAVA = 1,
7     ANDROID = 2
8
9 class Consts:
10     def __init__(self, DEBUG: bool, target: Target, **kwargs):
11         self.target = target
12         self.c_array_class_caches = set()
13         self.c_type_map = dict(
14             uint8_t = ['byte'],
15             uint16_t = ['short'],
16             uint32_t = ['int'],
17             uint64_t = ['long'],
18         )
19         self.java_type_map = dict(
20             String = "String"
21         )
22         self.java_hu_type_map = dict(
23             String = "String"
24         )
25
26         self.to_hu_conv_templates = dict(
27             ptr = '{human_type} {var_name}_hu_conv = null; if ({var_name} < 0 || {var_name} > 4096) { {var_name}_hu_conv = new {human_type}(null, {var_name}); }',
28             default = '{human_type} {var_name}_hu_conv = null; if ({var_name} < 0 || {var_name} > 4096) { {var_name}_hu_conv = new {human_type}(null, {var_name}); }'
29         )
30
31         self.bindings_header = """package org.ldk.impl;
32 import org.ldk.enums.*;
33 import org.ldk.impl.version;
34 import java.io.File;
35 import java.io.InputStream;
36 import java.io.IOException;
37 import java.nio.file.Files;
38 import java.nio.file.Path;
39 import java.nio.file.StandardCopyOption;
40
41 public class bindings {
42         public static class VecOrSliceDef {
43                 public long dataptr;
44                 public long datalen;
45                 public long stride;
46                 public VecOrSliceDef(long dataptr, long datalen, long stride) {
47                         this.dataptr = dataptr; this.datalen = datalen; this.stride = stride;
48                 }
49         }
50         static {
51                 try {
52                         // Try to load natively first, this works on Android and in testing.
53                         System.loadLibrary(\"lightningjni\");
54                 } catch (UnsatisfiedLinkError system_load_err) {
55                         // Otherwise try to load from the library jar.
56                         File tmpdir = new File(System.getProperty("java.io.tmpdir"), "ldk-java-nativelib");
57                         tmpdir.mkdir(); // If it fails to create, assume it was there already
58                         tmpdir.deleteOnExit();
59                         String libname = "liblightningjni_" + System.getProperty("os.name").replaceAll(" ", "") +
60                                 "-" + System.getProperty("os.arch").replaceAll(" ", "") + ".nativelib";
61                         try (InputStream is = bindings.class.getResourceAsStream("/" + libname)) {
62                                 Path libpath = new File(tmpdir.toPath().toString(), "liblightningjni.so").toPath();
63                                 Files.copy(is, libpath, StandardCopyOption.REPLACE_EXISTING);
64                                 Runtime.getRuntime().load(libpath.toString());
65                         } catch (Exception e) {
66                                 System.err.println("Failed to load LDK native library.");
67                                 System.err.println("System LDK native library load failed with: " + system_load_err);
68                                 System.err.println("Resource-based LDK native library load failed with: " + e);
69                                 throw new IllegalArgumentException(e);
70                         }
71                 }
72                 init(java.lang.Enum.class, VecOrSliceDef.class);
73                 init_class_cache();
74                 if (!get_lib_version_string().equals(version.get_ldk_java_bindings_version()))
75                         throw new IllegalArgumentException("Compiled LDK library and LDK class failes do not match");
76                 // Fetching the LDK versions from C also checks that the header and binaries match
77                 get_ldk_c_bindings_version();
78                 get_ldk_version();
79         }
80         static native void init(java.lang.Class c, java.lang.Class slicedef);
81         static native void init_class_cache();
82         static native String get_lib_version_string();
83
84         public static native String get_ldk_c_bindings_version();
85         public static native String get_ldk_version();
86
87         public static native boolean deref_bool(long ptr);
88         public static native long deref_long(long ptr);
89         public static native void free_heap_ptr(long ptr);
90         public static native byte[] read_bytes(long ptr, long len);
91         public static native byte[] get_u8_slice_bytes(long slice_ptr);
92         public static native long bytes_to_u8_vec(byte[] bytes);
93         public static native long new_txpointer_copy_data(byte[] txdata);
94         public static native void txpointer_free(long ptr);
95         public static native byte[] txpointer_get_buffer(long ptr);
96         public static native long vec_slice_len(long vec);
97         public static native long new_empty_slice_vec();
98
99 """
100         self.bindings_version_file = """package org.ldk.impl;
101
102 public class version {
103         public static String get_ldk_java_bindings_version() {
104                 return "<git_version_ldk_garbagecollected>";
105         }
106 }"""
107
108         self.bindings_footer = "}\n"
109
110         self.util_fn_pfx = """package org.ldk.structs;
111 import org.ldk.impl.bindings;
112 import org.ldk.enums.*;
113 import org.ldk.util.*;
114 import java.util.Arrays;
115 import java.lang.ref.Reference;
116 import javax.annotation.Nullable;
117
118 public class UtilMethods {
119 """
120         self.util_fn_sfx = "}"
121         self.common_base = """package org.ldk.structs;
122 import java.util.LinkedList;
123 class CommonBase {
124         long ptr;
125         LinkedList<Object> ptrs_to = new LinkedList();
126         protected CommonBase(long ptr) { assert ptr < 0 || ptr > 4096; this.ptr = ptr; }
127 }
128 """
129
130         self.txout_defn = """public class TxOut extends CommonBase {
131         /** The script_pubkey in this output */
132         public final byte[] script_pubkey;
133         /** The value, in satoshis, of this output */
134         public final long value;
135
136         TxOut(java.lang.Object _dummy, long ptr) {
137                 super(ptr);
138                 this.script_pubkey = bindings.TxOut_get_script_pubkey(ptr);
139                 this.value = bindings.TxOut_get_value(ptr);
140         }
141         public TxOut(long value, byte[] script_pubkey) {
142                 super(bindings.TxOut_new(script_pubkey, value));
143                 this.script_pubkey = bindings.TxOut_get_script_pubkey(ptr);
144                 this.value = bindings.TxOut_get_value(ptr);
145         }
146
147         @Override @SuppressWarnings(\"deprecation\")
148         protected void finalize() throws Throwable {
149                 super.finalize();
150                 if (ptr != 0) { bindings.TxOut_free(ptr); }
151         }
152 }"""
153
154         self.scalar_defn = """public class BigEndianScalar extends CommonBase {
155         /** The bytes of the scalar value, in big endian */
156         public final byte[] scalar_bytes;
157
158         BigEndianScalar(java.lang.Object _dummy, long ptr) {
159                 super(ptr);
160                 this.scalar_bytes = bindings.BigEndianScalar_get_bytes(ptr);
161         }
162         public BigEndianScalar(byte[] scalar_bytes) {
163                 super(bindings.BigEndianScalar_new(scalar_bytes));
164                 this.scalar_bytes = bindings.BigEndianScalar_get_bytes(ptr);
165         }
166
167         @Override @SuppressWarnings(\"deprecation\")
168         protected void finalize() throws Throwable {
169                 super.finalize();
170                 if (ptr != 0) { bindings.BigEndianScalar_free(ptr); }
171         }
172 }"""
173
174
175         self.c_file_pfx = """#include <jni.h>
176 // On OSX jlong (ie long long) is not equivalent to int64_t, so we override here
177 #define int64_t jlong
178 #include \"org_ldk_impl_bindings.h\"
179 #include <lightning.h>
180 #include <string.h>
181 #include <stdatomic.h>
182 #include <stdlib.h>
183
184 #define LIKELY(v) __builtin_expect(!!(v), 1)
185 #define UNLIKELY(v) __builtin_expect(!!(v), 0)
186
187 """
188
189         if self.target == Target.ANDROID:
190             self.c_file_pfx = self.c_file_pfx + """
191 #include <android/log.h>
192 #define DEBUG_PRINT(...) __android_log_print(ANDROID_LOG_ERROR, "LDK", __VA_ARGS__)
193
194 #include <unistd.h>
195 #include <pthread.h>
196 static void* redirect_stderr(void* ignored) {
197         int pipes[2];
198         pipe(pipes);
199         dup2(pipes[1], STDERR_FILENO);
200         char buf[8192];
201         memset(buf, 0, 8192);
202         ssize_t len;
203         while ((len = read(pipes[0], buf, 8191)) > 0) {
204                 DEBUG_PRINT("%s\\n", buf);
205                 memset(buf, 0, 8192);
206         }
207         DEBUG_PRINT("End of stderr???\\n");
208         return 0;
209 }
210 void __attribute__((constructor)) spawn_stderr_redirection() {
211         pthread_t thread;
212         pthread_create(&thread, NULL, &redirect_stderr, NULL);
213 }
214 """
215         else:
216             self.c_file_pfx = self.c_file_pfx + "#define DEBUG_PRINT(...) fprintf(stderr, __VA_ARGS__)\n"
217
218         if not DEBUG or sys.platform == "darwin":
219             self.c_file_pfx = self.c_file_pfx + """#define MALLOC(a, _) malloc(a)
220 #define FREE(p) if ((uint64_t)(p) > 4096) { free(p); }
221 #define CHECK_ACCESS(p)
222 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v)
223 """
224         if not DEBUG:
225             self.c_file_pfx += """#define DO_ASSERT(a) (void)(a)
226 #define CHECK(a)
227 """
228         if DEBUG:
229             self.c_file_pfx = self.c_file_pfx + """#include <assert.h>
230 // Always run a, then assert it is true:
231 #define DO_ASSERT(a) do { bool _assert_val = (a); assert(_assert_val); } while(0)
232 // Assert a is true or do nothing
233 #define CHECK(a) DO_ASSERT(a)
234
235 void __attribute__((constructor)) debug_log_version() {
236         if (check_get_ldk_version() == NULL)
237                 DEBUG_PRINT("LDK version did not match the header we built against\\n");
238         if (check_get_ldk_bindings_version() == NULL)
239                 DEBUG_PRINT("LDK C Bindings version did not match the header we built against\\n");
240         DEBUG_PRINT("Loaded LDK-Java Bindings with LDK %s and LDK-C-Bindings %s\\n", check_get_ldk_version(), check_get_ldk_bindings_version());
241 }
242 """
243
244             if sys.platform != "darwin":
245                 self.c_file_pfx += """
246 // Running a leak check across all the allocations and frees of the JDK is a mess,
247 // so instead we implement our own naive leak checker here, relying on the -wrap
248 // linker option to wrap malloc/calloc/realloc/free, tracking everyhing allocated
249 // and free'd in Rust or C across the generated bindings shared library.
250 #include <threads.h>
251 """
252
253                 if self.target == Target.ANDROID:
254                     self.c_file_pfx = self.c_file_pfx + """
255 #include <unwind.h>
256 #include <dlfcn.h>
257
258 // Implement the execinfo functions using _Unwind_backtrace. This seems to miss many Rust
259 // symbols, so we only use it on Android, where execinfo.h is unavailable.
260
261 struct BacktraceState {
262         void** current;
263         void** end;
264 };
265 static _Unwind_Reason_Code unwind_callback(struct _Unwind_Context* context, void* arg) {
266         struct BacktraceState* state = (struct BacktraceState*)arg;
267         uintptr_t pc = _Unwind_GetIP(context);
268         if (pc) {
269                 if (state->current == state->end) {
270                         return _URC_END_OF_STACK;
271                 } else {
272                         *state->current++ = (void*)(pc);
273                 }
274         }
275         return _URC_NO_REASON;
276 }
277
278 int backtrace(void** buffer, int max) {
279         struct BacktraceState state = { buffer, buffer + max };
280         _Unwind_Backtrace(unwind_callback, &state);
281         return state.current - buffer;
282 }
283
284 void backtrace_symbols_fd(void ** buffer, int count, int _fd) {
285         for (int idx = 0; idx < count; ++idx) {
286                 Dl_info info;
287                 if (dladdr(buffer[idx], &info) && info.dli_sname) {
288                         DEBUG_PRINT("%p: %s", buffer[idx], info.dli_sname);
289                 } else {
290                         DEBUG_PRINT("%p: ???", buffer[idx]);
291                 }
292         }
293 }
294 """
295                 else:
296                     self.c_file_pfx = self.c_file_pfx + "#include <execinfo.h>\n"
297                 self.c_file_pfx = self.c_file_pfx + """
298 #include <unistd.h>
299 #include <pthread.h>
300 static pthread_mutex_t allocation_mtx;
301
302 void __attribute__((constructor)) init_mtx() {
303         DO_ASSERT(!pthread_mutex_init(&allocation_mtx, NULL));
304 }
305
306 #define BT_MAX 128
307 typedef struct allocation {
308         struct allocation* next;
309         void* ptr;
310         const char* struct_name;
311         void* bt[BT_MAX];
312         int bt_len;
313         unsigned long alloc_len;
314 } allocation;
315 static allocation* allocation_ll = NULL;
316
317 void* __real_malloc(size_t len);
318 void* __real_calloc(size_t nmemb, size_t len);
319 static void new_allocation(void* res, const char* struct_name, size_t len) {
320         allocation* new_alloc = __real_malloc(sizeof(allocation));
321         new_alloc->ptr = res;
322         new_alloc->struct_name = struct_name;
323         new_alloc->bt_len = backtrace(new_alloc->bt, BT_MAX);
324         new_alloc->alloc_len = len;
325         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
326         new_alloc->next = allocation_ll;
327         allocation_ll = new_alloc;
328         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
329 }
330 static void* MALLOC(size_t len, const char* struct_name) {
331         void* res = __real_malloc(len);
332         new_allocation(res, struct_name, len);
333         return res;
334 }
335 void __real_free(void* ptr);
336 static void alloc_freed(void* ptr) {
337         allocation* p = NULL;
338         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
339         allocation* it = allocation_ll;
340         while (it->ptr != ptr) {
341                 p = it; it = it->next;
342                 if (it == NULL) {
343                         DEBUG_PRINT("ERROR: Tried to free unknown pointer %p at:\\n", ptr);
344                         void* bt[BT_MAX];
345                         int bt_len = backtrace(bt, BT_MAX);
346                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
347                         DEBUG_PRINT("\\n\\n");
348                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
349                         return; // addrsan should catch malloc-unknown and print more info than we have
350                 }
351         }
352         if (p) { p->next = it->next; } else { allocation_ll = it->next; }
353         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
354         DO_ASSERT(it->ptr == ptr);
355         __real_free(it);
356 }
357 static void FREE(void* ptr) {
358         if ((uint64_t)ptr <= 4096) return; // Rust loves to create pointers to the NULL page for dummys
359         alloc_freed(ptr);
360         __real_free(ptr);
361 }
362
363 void* __wrap_malloc(size_t len) {
364         void* res = __real_malloc(len);
365         new_allocation(res, "malloc call", len);
366         return res;
367 }
368 void* __wrap_calloc(size_t nmemb, size_t len) {
369         void* res = __real_calloc(nmemb, len);
370         new_allocation(res, "calloc call", len);
371         return res;
372 }
373 void __wrap_free(void* ptr) {
374         if (ptr == NULL) return;
375         alloc_freed(ptr);
376         __real_free(ptr);
377 }
378
379 static void CHECK_ACCESS(const void* ptr) {
380         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
381         allocation* it = allocation_ll;
382         while (it->ptr != ptr) {
383                 it = it->next;
384                 if (it == NULL) {
385                         DEBUG_PRINT("ERROR: Tried to access unknown pointer %p at:\\n", ptr);
386                         void* bt[BT_MAX];
387                         int bt_len = backtrace(bt, BT_MAX);
388                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
389                         DEBUG_PRINT("\\n\\n");
390                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
391                         return; // addrsan should catch and print more info than we have
392                 }
393         }
394         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
395 }
396 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v) \\
397         if (v.is_owned && v.inner != NULL) { \\
398                 const void *p = __unmangle_inner_ptr(v.inner); \\
399                 if (p != NULL) { \\
400                         CHECK_ACCESS(p); \\
401                 } \\
402         }
403
404 void* __real_realloc(void* ptr, size_t newlen);
405 void* __wrap_realloc(void* ptr, size_t len) {
406         if (ptr != NULL) alloc_freed(ptr);
407         void* res = __real_realloc(ptr, len);
408         new_allocation(res, "realloc call", len);
409         return res;
410 }
411 void __wrap_reallocarray(void* ptr, size_t new_sz) {
412         // Rust doesn't seem to use reallocarray currently
413         DO_ASSERT(false);
414 }
415
416 void __attribute__((destructor)) check_leaks() {
417         unsigned long alloc_count = 0;
418         unsigned long alloc_size = 0;
419         DEBUG_PRINT("The following LDK-allocated blocks still remain.\\n");
420         DEBUG_PRINT("Note that this is only accurate if System.gc(); System.runFinalization()\\n");
421         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
422         for (allocation* a = allocation_ll; a != NULL; a = a->next) {
423                 DEBUG_PRINT("%s %p (%lu bytes) remains:\\n", a->struct_name, a->ptr, a->alloc_len);
424                 backtrace_symbols_fd(a->bt, a->bt_len, STDERR_FILENO);
425                 DEBUG_PRINT("\\n\\n");
426                 alloc_count++;
427                 alloc_size += a->alloc_len;
428         }
429         DEBUG_PRINT("%lu allocations remained for %lu bytes.\\n", alloc_count, alloc_size);
430         DEBUG_PRINT("Note that this is only accurate if System.gc(); System.runFinalization()\\n");
431         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
432 }
433 """
434         self.c_file_pfx = self.c_file_pfx + """
435 static jmethodID ordinal_meth = NULL;
436 static jmethodID slicedef_meth = NULL;
437 static jclass slicedef_cls = NULL;
438 JNIEXPORT void Java_org_ldk_impl_bindings_init(JNIEnv * env, jclass _b, jclass enum_class, jclass slicedef_class) {
439         ordinal_meth = (*env)->GetMethodID(env, enum_class, "ordinal", "()I");
440         CHECK(ordinal_meth != NULL);
441         slicedef_meth = (*env)->GetMethodID(env, slicedef_class, "<init>", "(JJJ)V");
442         CHECK(slicedef_meth != NULL);
443         slicedef_cls = (*env)->NewGlobalRef(env, slicedef_class);
444         CHECK(slicedef_cls != NULL);
445 }
446
447 JNIEXPORT jboolean JNICALL Java_org_ldk_impl_bindings_deref_1bool (JNIEnv * env, jclass _a, jlong ptr) {
448         return *((bool*)ptr);
449 }
450 JNIEXPORT jlong JNICALL Java_org_ldk_impl_bindings_deref_1long (JNIEnv * env, jclass _a, jlong ptr) {
451         return *((long*)ptr);
452 }
453 JNIEXPORT void JNICALL Java_org_ldk_impl_bindings_free_1heap_1ptr (JNIEnv * env, jclass _a, jlong ptr) {
454         FREE((void*)ptr);
455 }
456 JNIEXPORT jbyteArray JNICALL Java_org_ldk_impl_bindings_read_1bytes (JNIEnv * env, jclass _b, jlong ptr, jlong len) {
457         jbyteArray ret_arr = (*env)->NewByteArray(env, len);
458         (*env)->SetByteArrayRegion(env, ret_arr, 0, len, (unsigned char*)ptr);
459         return ret_arr;
460 }
461 JNIEXPORT jbyteArray JNICALL Java_org_ldk_impl_bindings_get_1u8_1slice_1bytes (JNIEnv * env, jclass _b, jlong slice_ptr) {
462         LDKu8slice *slice = (LDKu8slice*)slice_ptr;
463         jbyteArray ret_arr = (*env)->NewByteArray(env, slice->datalen);
464         (*env)->SetByteArrayRegion(env, ret_arr, 0, slice->datalen, slice->data);
465         return ret_arr;
466 }
467 JNIEXPORT int64_t impl_bindings_bytes_1to_1u8_1vec (JNIEnv * env, jclass _b, jbyteArray bytes) {
468         LDKCVec_u8Z *vec = (LDKCVec_u8Z*)MALLOC(sizeof(LDKCVec_u8Z), "LDKCVec_u8");
469         vec->datalen = (*env)->GetArrayLength(env, bytes);
470         vec->data = (uint8_t*)MALLOC(vec->datalen, "LDKCVec_u8Z Bytes");
471         (*env)->GetByteArrayRegion (env, bytes, 0, vec->datalen, vec->data);
472         return (uint64_t)vec;
473 }
474 JNIEXPORT jbyteArray JNICALL Java_org_ldk_impl_bindings_txpointer_1get_1buffer (JNIEnv * env, jclass _b, jlong ptr) {
475         LDKTransaction *txdata = (LDKTransaction*)ptr;
476         LDKu8slice slice;
477         slice.data = txdata->data;
478         slice.datalen = txdata->datalen;
479         return Java_org_ldk_impl_bindings_get_1u8_1slice_1bytes(env, _b, (uint64_t)&slice);
480 }
481 JNIEXPORT int64_t JNICALL Java_org_ldk_impl_bindings_new_1txpointer_1copy_1data (JNIEnv * env, jclass _b, jbyteArray bytes) {
482         LDKTransaction *txdata = (LDKTransaction*)MALLOC(sizeof(LDKTransaction), "LDKTransaction");
483         txdata->datalen = (*env)->GetArrayLength(env, bytes);
484         txdata->data = (uint8_t*)MALLOC(txdata->datalen, "Tx Data Bytes");
485         txdata->data_is_owned = false;
486         (*env)->GetByteArrayRegion (env, bytes, 0, txdata->datalen, txdata->data);
487         return (uint64_t)txdata;
488 }
489 JNIEXPORT void JNICALL Java_org_ldk_impl_bindings_txpointer_1free (JNIEnv * env, jclass _b, jlong ptr) {
490         LDKTransaction *tx = (LDKTransaction*)ptr;
491         tx->data_is_owned = true;
492         Transaction_free(*tx);
493         FREE((void*)ptr);
494 }
495 JNIEXPORT jlong JNICALL Java_org_ldk_impl_bindings_vec_1slice_1len (JNIEnv * env, jclass _a, jlong ptr) {
496         // Check offsets of a few Vec types are all consistent as we're meant to be generic across types
497         _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKCVec_SignatureZ, datalen), "Vec<*> needs to be mapped identically");
498         _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKCVec_MessageSendEventZ, datalen), "Vec<*> needs to be mapped identically");
499         _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKCVec_EventZ, datalen), "Vec<*> needs to be mapped identically");
500         _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKCVec_C2Tuple_usizeTransactionZZ, datalen), "Vec<*> needs to be mapped identically");
501         LDKCVec_u8Z *vec = (LDKCVec_u8Z*)ptr;
502         return (uint64_t)vec->datalen;
503 }
504 JNIEXPORT int64_t JNICALL Java_org_ldk_impl_bindings_new_1empty_1slice_1vec (JNIEnv * env, jclass _b) {
505         // Check sizes of a few Vec types are all consistent as we're meant to be generic across types
506         _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKCVec_SignatureZ), "Vec<*> needs to be mapped identically");
507         _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKCVec_MessageSendEventZ), "Vec<*> needs to be mapped identically");
508         _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKCVec_EventZ), "Vec<*> needs to be mapped identically");
509         _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKCVec_C2Tuple_usizeTransactionZZ), "Vec<*> needs to be mapped identically");
510         LDKCVec_u8Z *vec = (LDKCVec_u8Z*)MALLOC(sizeof(LDKCVec_u8Z), "Empty LDKCVec");
511         vec->data = NULL;
512         vec->datalen = 0;
513         return (uint64_t)vec;
514 }
515
516 // We assume that CVec_u8Z and u8slice are the same size and layout (and thus pointers to the two can be mixed)
517 _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKu8slice), "Vec<u8> and [u8] need to have been mapped identically");
518 _Static_assert(offsetof(LDKCVec_u8Z, data) == offsetof(LDKu8slice, data), "Vec<u8> and [u8] need to have been mapped identically");
519 _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKu8slice, datalen), "Vec<u8> and [u8] need to have been mapped identically");
520
521 _Static_assert(sizeof(jlong) == sizeof(int64_t), "We assume that j-types are the same as C types");
522 _Static_assert(sizeof(jbyte) == sizeof(char), "We assume that j-types are the same as C types");
523 _Static_assert(sizeof(void*) <= 8, "Pointers must fit into 64 bits");
524
525 typedef jlongArray int64_tArray;
526 typedef jbyteArray int8_tArray;
527
528 static inline jstring str_ref_to_java(JNIEnv *env, const char* chars, size_t len) {
529         // Sadly we need to create a temporary because Java can't accept a char* without a 0-terminator
530         char* conv_buf = MALLOC(len + 1, "str conv buf");
531         memcpy(conv_buf, chars, len);
532         conv_buf[len] = 0;
533         jstring ret = (*env)->NewStringUTF(env, conv_buf);
534         FREE(conv_buf);
535         return ret;
536 }
537 static inline LDKStr java_to_owned_str(JNIEnv *env, jstring str) {
538         uint64_t str_len = (*env)->GetStringUTFLength(env, str);
539         char* newchars = MALLOC(str_len + 1, "String chars");
540         const char* jchars = (*env)->GetStringUTFChars(env, str, NULL);
541         memcpy(newchars, jchars, str_len);
542         newchars[str_len] = 0;
543         (*env)->ReleaseStringUTFChars(env, str, jchars);
544         LDKStr res = {
545                 .chars = newchars,
546                 .len = str_len,
547                 .chars_is_owned = true
548         };
549         return res;
550 }
551
552 JNIEXPORT jstring JNICALL Java_org_ldk_impl_bindings_get_1ldk_1c_1bindings_1version(JNIEnv *env, jclass _c) {
553         return str_ref_to_java(env, check_get_ldk_bindings_version(), strlen(check_get_ldk_bindings_version()));
554 }
555 JNIEXPORT jstring JNICALL Java_org_ldk_impl_bindings_get_1ldk_1version(JNIEnv *env, jclass _c) {
556         return str_ref_to_java(env, check_get_ldk_version(), strlen(check_get_ldk_version()));
557 }
558 #include "version.c"
559 """
560         self.c_version_file = """JNIEXPORT jstring JNICALL Java_org_ldk_impl_bindings_get_1lib_1version_1string(JNIEnv *env, jclass _c) {
561         return str_ref_to_java(env, "<git_version_ldk_garbagecollected>", strlen("<git_version_ldk_garbagecollected>"));
562 }"""
563
564         self.hu_struct_file_prefix = """package org.ldk.structs;
565
566 import org.ldk.impl.bindings;
567 import org.ldk.enums.*;
568 import org.ldk.util.*;
569 import java.util.Arrays;
570 import java.lang.ref.Reference;
571 import javax.annotation.Nullable;
572
573 """
574         self.c_fn_ty_pfx = "JNIEXPORT "
575         self.c_fn_args_pfx = "JNIEnv *env, jclass clz"
576         self.file_ext = ".java"
577         self.ptr_c_ty = "int64_t"
578         self.ptr_native_ty = "long"
579         self.usize_c_ty = "int64_t"
580         self.usize_native_ty = "long"
581         self.native_zero_ptr = "0"
582         self.result_c_ty = "jclass"
583         self.ptr_arr = "jobjectArray"
584         self.is_arr_some_check = ("", " != NULL")
585         self.get_native_arr_len_call = ("(*env)->GetArrayLength(env, ", ")")
586
587     def construct_jenv(self):
588         res =  "JNIEnv *env;\n"
589         res += "jint get_jenv_res = (*j_calls->vm)->GetEnv(j_calls->vm, (void**)&env, JNI_VERSION_1_6);\n"
590         res += "if (get_jenv_res == JNI_EDETACHED) {\n"
591         if self.target == Target.ANDROID:
592             res += "\tDO_ASSERT((*j_calls->vm)->AttachCurrentThread(j_calls->vm, &env, NULL) == JNI_OK);\n"
593         else:
594             res += "\tDO_ASSERT((*j_calls->vm)->AttachCurrentThread(j_calls->vm, (void**)&env, NULL) == JNI_OK);\n"
595         res += "} else {\n"
596         res += "\tDO_ASSERT(get_jenv_res == JNI_OK);\n"
597         res += "}\n"
598         return res
599     def deconstruct_jenv(self):
600         res = "if (get_jenv_res == JNI_EDETACHED) {\n"
601         res += "\tDO_ASSERT((*j_calls->vm)->DetachCurrentThread(j_calls->vm) == JNI_OK);\n"
602         res += "}\n"
603         return res
604
605     def release_native_arr_ptr_call(self, ty_info, arr_var, arr_ptr_var):
606         if ty_info.subty is None or not ty_info.subty.c_ty.endswith("Array"):
607             return "(*env)->ReleasePrimitiveArrayCritical(env, " + arr_var + ", " + arr_ptr_var + ", 0)"
608         return None
609     def create_native_arr_call(self, arr_len, ty_info):
610         if ty_info.c_ty == "int8_tArray":
611             return "(*env)->NewByteArray(env, " + arr_len + ")"
612         elif ty_info.subty.c_ty.endswith("Array"):
613             clz_var = ty_info.java_fn_ty_arg[1:].replace("[", "arr_of_")
614             self.c_array_class_caches.add(clz_var)
615             return "(*env)->NewObjectArray(env, " + arr_len + ", " + clz_var + "_clz, NULL);\n"
616         else:
617             return "(*env)->New" + ty_info.java_ty.strip("[]").title() + "Array(env, " + arr_len + ")"
618     def set_native_arr_contents(self, arr_name, arr_len, ty_info):
619         if ty_info.c_ty == "int8_tArray":
620             return ("(*env)->SetByteArrayRegion(env, " + arr_name + ", 0, " + arr_len + ", ", ")")
621         else:
622             assert False
623     def get_native_arr_contents(self, arr_name, dest_name, arr_len, ty_info, copy):
624         if ty_info.c_ty == "int8_tArray":
625             if copy:
626                 return "(*env)->GetByteArrayRegion(env, " + arr_name + ", 0, " + arr_len + ", " + dest_name + ")"
627             else:
628                 return "(*env)->GetByteArrayElements (env, " + arr_name + ", NULL)"
629         elif not ty_info.java_ty[:len(ty_info.java_ty) - 2].endswith("[]"):
630             return "(*env)->Get" + ty_info.subty.java_ty.title() + "ArrayElements (env, " + arr_name + ", NULL)"
631         else:
632             return None
633     def get_native_arr_elem(self, arr_name, idxc, ty_info):
634         if self.get_native_arr_contents(arr_name, "", "", ty_info, False) is None:
635             return "(*env)->GetObjectArrayElement(env, " + arr_name + ", " + idxc + ")"
636         else:
637             assert False # Only called if above is None
638     def get_native_arr_ptr_call(self, ty_info):
639         if ty_info.subty is not None and ty_info.subty.c_ty.endswith("Array"):
640             return None
641         return ("(*env)->GetPrimitiveArrayCritical(env, ", ", NULL)")
642     def get_native_arr_entry_call(self, ty_info, arr_name, idxc, entry_access):
643         if ty_info.subty is None or not ty_info.subty.c_ty.endswith("Array"):
644             return None
645         return "(*env)->SetObjectArrayElement(env, " + arr_name + ", " + idxc + ", " + entry_access + ")"
646     def cleanup_native_arr_ref_contents(self, arr_name, dest_name, arr_len, ty_info):
647         if ty_info.c_ty == "int8_tArray":
648             return "(*env)->ReleaseByteArrayElements(env, " + arr_name + ", (int8_t*)" + dest_name + ", 0);"
649         else:
650             return "(*env)->Release" + ty_info.java_ty.strip("[]").title() + "ArrayElements(env, " + arr_name + ", " + dest_name + ", 0)"
651
652     def map_hu_array_elems(self, arr_name, conv_name, arr_ty, elem_ty):
653         if elem_ty.java_ty == "long" and elem_ty.java_hu_ty != "long":
654             return arr_name + " != null ? Arrays.stream(" + arr_name + ").mapToLong(" + conv_name + " -> " + elem_ty.from_hu_conv[0] + ").toArray() : null"
655         elif elem_ty.java_ty == "long":
656             return arr_name + " != null ? Arrays.stream(" + arr_name + ").map(" + conv_name + " -> " + elem_ty.from_hu_conv[0] + ").toArray() : null"
657         elif elem_ty.java_hu_ty == "UInt5":
658             return arr_name + " != null ? InternalUtils.convUInt5Array(" + arr_name + ") : null"
659         elif elem_ty.java_hu_ty == "WitnessVersion":
660             return arr_name + " != null ? InternalUtils.convWitnessVersionArray(" + arr_name + ") : null"
661         else:
662             return arr_name + " != null ? Arrays.stream(" + arr_name + ").map(" + conv_name + " -> " + elem_ty.from_hu_conv[0] + ").toArray(" + arr_ty.java_ty + "::new) : null"
663
664     def str_ref_to_native_call(self, var_name, str_len):
665         return "str_ref_to_java(env, " + var_name + ", " + str_len + ")"
666     def str_ref_to_c_call(self, var_name):
667         return "java_to_owned_str(env, " + var_name + ")"
668     def str_to_hu_conv(self, var_name):
669         return None
670     def str_from_hu_conv(self, var_name):
671         return None
672
673     def c_fn_name_define_pfx(self, fn_name, has_args):
674         if has_args:
675             return "JNICALL Java_org_ldk_impl_bindings_" + fn_name.replace("_", "_1") + "(JNIEnv *env, jclass clz, "
676         return "JNICALL Java_org_ldk_impl_bindings_" + fn_name.replace("_", "_1") + "(JNIEnv *env, jclass clz"
677
678     def init_str(self):
679         res = ""
680         for ty in sorted(self.c_array_class_caches):
681             res = res + "static jclass " + ty + "_clz = NULL;\n"
682         res = res + "JNIEXPORT void Java_org_ldk_impl_bindings_init_1class_1cache(JNIEnv * env, jclass clz) {\n"
683         for ty in sorted(self.c_array_class_caches):
684             res = res + "\t" + ty + "_clz = (*env)->FindClass(env, \"" + ty.replace("arr_of_", "[") + "\");\n"
685             res = res + "\tCHECK(" + ty + "_clz != NULL);\n"
686             res = res + "\t" + ty + "_clz = (*env)->NewGlobalRef(env, " + ty + "_clz);\n"
687         res = res + "}\n"
688         return res
689
690     def var_decl_statement(self, ty_string, var_name, statement):
691         return ty_string + " " + var_name + " = " + statement
692
693     def get_java_arr_len(self, arr_name):
694         return arr_name + ".length"
695     def get_java_arr_elem(self, elem_ty, arr_name, idx):
696         return arr_name + "[" + idx + "]"
697     def constr_hu_array(self, ty_info, arr_len):
698         base_ty = ty_info.subty.java_hu_ty.split("[")[0].split("<")[0]
699         conv = "new " + base_ty + "[" + arr_len + "]"
700         if "[" in ty_info.subty.java_hu_ty.split("<")[0]:
701             # Do a bit of a dance to move any excess [] to the end
702             conv += "[" + ty_info.subty.java_hu_ty.split("<")[0].split("[")[1]
703         return conv
704     def cleanup_converted_native_array(self, ty_info, arr_name):
705         return None
706
707     def primitive_arr_from_hu(self, mapped_ty, fixed_len, arr_name):
708         if fixed_len is not None:
709             return ("InternalUtils.check_arr_len(" + arr_name + ", " + fixed_len + ")", "")
710         return None
711     def primitive_arr_to_hu(self, primitive_ty, fixed_len, arr_name, conv_name):
712         return None
713
714     def java_arr_ty_str(self, elem_ty_str):
715         return elem_ty_str + "[]"
716
717     def for_n_in_range(self, n, minimum, maximum):
718         return "for (int " + n + " = " + minimum + "; " + n + " < " + maximum + "; " + n + "++) {"
719     def for_n_in_arr(self, n, arr_name, arr_elem_ty):
720         return ("for (" + arr_elem_ty.java_hu_ty + " " + n + ": " + arr_name + ") { ", " }")
721
722     def get_ptr(self, var):
723         return var + ".ptr"
724     def set_null_skip_free(self, var):
725         return var + ".ptr" + " = 0;"
726
727     def add_ref(self, holder, referent):
728         return "if (" + holder + " != null) { " + holder + ".ptrs_to.add(" + referent + "); }"
729
730     def fully_qualified_hu_ty_path(self, ty):
731         if ty.java_fn_ty_arg.startswith("L") and ty.java_fn_ty_arg.endswith(";"):
732             return ty.java_fn_ty_arg.strip("L;").replace("/", ".")
733         if ty.java_hu_ty == "UnqualifiedError" or ty.java_hu_ty == "UInt5" or ty.java_hu_ty == "WitnessVersion":
734             return "org.ldk.util." + ty.java_hu_ty
735         if not ty.is_native_primitive and ty.rust_obj is not None and not "[]" in ty.java_hu_ty:
736             return "org.ldk.structs." + ty.java_hu_ty
737         return ty.java_hu_ty
738
739     def native_c_unitary_enum_map(self, struct_name, variants, enum_doc_comment):
740         out_java_enum = "package org.ldk.enums;\n\n"
741         out_java = ""
742         out_c = ""
743         out_c += "static inline LDK" + struct_name + " LDK" + struct_name + "_from_java(" + self.c_fn_args_pfx + ") {\n"
744         out_c += "\tjint ord = (*env)->CallIntMethod(env, clz, ordinal_meth);\n"
745         out_c += "\tif (UNLIKELY((*env)->ExceptionCheck(env))) {\n"
746         out_c += "\t\t(*env)->ExceptionDescribe(env);\n"
747         out_c += "\t\t(*env)->FatalError(env, \"A call to " + struct_name + ".ordinal() from rust threw an exception.\");\n"
748         out_c += "\t}\n"
749         out_c += "\tswitch (ord) {\n"
750
751         if enum_doc_comment is not None:
752             out_java_enum += "/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
753         out_java_enum += "public enum " + struct_name + " {\n"
754         ord_v = 0
755         for var, var_docs in variants:
756             if var_docs is not None:
757                 out_java_enum += "\t/**\n\t * " + var_docs.replace("\n", "\n\t * ") + "\n\t */\n"
758             out_java_enum += "\t" + var + ",\n"
759             out_c = out_c + "\t\tcase %d: return %s;\n" % (ord_v, var)
760             ord_v = ord_v + 1
761         out_java_enum = out_java_enum + "\t; static native void init();\n"
762         out_java_enum = out_java_enum + "\tstatic { init(); }\n"
763         out_java_enum = out_java_enum + "}"
764         out_java = out_java + "\tstatic { " + struct_name + ".values(); /* Force enum statics to run */ }\n"
765         out_c += "\t}\n"
766         out_c += "\t(*env)->FatalError(env, \"A call to " + struct_name + ".ordinal() from rust returned an invalid value.\");\n"
767         out_c += "\tabort(); // Unreachable, but will let the compiler know we don't return here\n"
768         out_c += "}\n"
769
770         out_c = out_c + "static jclass " + struct_name + "_class = NULL;\n"
771         for var, _ in variants:
772             out_c = out_c + "static jfieldID " + struct_name + "_" + var + " = NULL;\n"
773         out_c = out_c + self.c_fn_ty_pfx + "void JNICALL Java_org_ldk_enums_" + struct_name.replace("_", "_1") + "_init (" + self.c_fn_args_pfx + ") {\n"
774         out_c = out_c + "\t" + struct_name + "_class = (*env)->NewGlobalRef(env, clz);\n"
775         out_c = out_c + "\tCHECK(" + struct_name + "_class != NULL);\n"
776         for var, _ in variants:
777             out_c = out_c + "\t" + struct_name + "_" + var + " = (*env)->GetStaticFieldID(env, " + struct_name + "_class, \"" + var + "\", \"Lorg/ldk/enums/" + struct_name + ";\");\n"
778             out_c = out_c + "\tCHECK(" + struct_name + "_" + var + " != NULL);\n"
779         out_c = out_c + "}\n"
780         out_c = out_c + "static inline jclass LDK" + struct_name + "_to_java(JNIEnv *env, LDK" + struct_name + " val) {\n"
781         out_c = out_c + "\tswitch (val) {\n"
782         ord_v = 0
783         for var, _ in variants:
784             out_c = out_c + "\t\tcase " + var + ":\n"
785             out_c = out_c + "\t\t\treturn (*env)->GetStaticObjectField(env, " + struct_name + "_class, " + struct_name + "_" + var + ");\n"
786             ord_v = ord_v + 1
787         out_c = out_c + "\t\tdefault: abort();\n"
788         out_c = out_c + "\t}\n"
789         out_c = out_c + "}\n\n"
790
791         return (out_c, out_java_enum, out_java)
792
793     def c_unitary_enum_to_native_call(self, ty_info):
794         return (ty_info.rust_obj + "_to_java(env, ", ")")
795     def native_unitary_enum_to_c_call(self, ty_info):
796         return (ty_info.rust_obj + "_from_java(env, ", ")")
797
798     def c_complex_enum_pfx(self, struct_name, variants, init_meth_jty_strs):
799         out_c = ""
800         for var in variants:
801             out_c = out_c + "static jclass " + struct_name + "_" + var + "_class = NULL;\n"
802             out_c = out_c + "static jmethodID " + struct_name + "_" + var + "_meth = NULL;\n"
803         out_c = out_c + self.c_fn_ty_pfx + "void JNICALL Java_org_ldk_impl_bindings_00024" + struct_name.replace("_", "_1") + "_init (" + self.c_fn_args_pfx + ") {\n"
804         for var_name in variants:
805             out_c += "\t" + struct_name + "_" + var_name + "_class =\n"
806             out_c += "\t\t(*env)->NewGlobalRef(env, (*env)->FindClass(env, \"org/ldk/impl/bindings$" + struct_name + "$" + var_name + "\"));\n"
807             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_class != NULL);\n"
808             out_c += "\t" + struct_name + "_" + var_name + "_meth = (*env)->GetMethodID(env, " + struct_name + "_" + var_name + "_class, \"<init>\", \"(" + init_meth_jty_strs[var_name] + ")V\");\n"
809             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_meth != NULL);\n"
810         out_c = out_c + "}\n"
811         return out_c
812
813     def c_complex_enum_pass_ty(self, struct_name):
814         return "jobject"
815
816     def c_constr_native_complex_enum(self, struct_name, variant, c_params):
817         ret = "(*env)->NewObject(env, " + struct_name + "_" + variant + "_class, " + struct_name + "_" + variant + "_meth"
818         for param in c_params:
819             ret = ret + ", " + param
820         return ret + ")"
821
822     def native_c_map_trait(self, struct_name, field_vars, flattened_field_vars, field_fns, trait_doc_comment):
823         out_java_trait = ""
824         out_java = ""
825
826         # First generate most of the Java code, note that we need information about java method argument strings for C
827         out_java_trait = out_java_trait + self.hu_struct_file_prefix
828         if trait_doc_comment is not None:
829             out_java_trait += "/**\n * " + trait_doc_comment.replace("\n", "\n * ") + "\n */\n"
830         out_java_trait += "@SuppressWarnings(\"unchecked\") // We correctly assign various generic arrays\n"
831         out_java_trait = out_java_trait + "public class " + struct_name.replace("LDK","") + " extends CommonBase {\n"
832         out_java_trait = out_java_trait + "\tfinal bindings." + struct_name + " bindings_instance;\n"
833         out_java_trait = out_java_trait + "\t" + struct_name.replace("LDK", "") + "(Object _dummy, long ptr) { super(ptr); bindings_instance = null; }\n"
834         out_java_trait = out_java_trait + "\tprivate " + struct_name.replace("LDK", "") + "(bindings." + struct_name + " arg"
835         for var in flattened_field_vars:
836             if isinstance(var, ConvInfo):
837                 out_java_trait = out_java_trait + ", " + var.java_hu_ty + " " + var.arg_name
838             else:
839                 out_java_trait = out_java_trait + ", bindings." + var[0] + " " + var[1]
840         out_java_trait = out_java_trait + ") {\n"
841         out_java_trait = out_java_trait + "\t\tsuper(bindings." + struct_name + "_new(arg"
842         for var in flattened_field_vars:
843             if isinstance(var, ConvInfo):
844                 if var.from_hu_conv is not None:
845                     out_java_trait = out_java_trait + ", " + var.from_hu_conv[0]
846                 else:
847                     out_java_trait = out_java_trait + ", " + var.arg_name
848             else:
849                 out_java_trait = out_java_trait + ", " + var[1]
850         out_java_trait = out_java_trait + "));\n"
851         out_java_trait = out_java_trait + "\t\tthis.ptrs_to.add(arg);\n"
852         for var in flattened_field_vars:
853             if isinstance(var, ConvInfo):
854                 if var.from_hu_conv is not None and var.from_hu_conv[1] != "":
855                     out_java_trait = out_java_trait + "\t\t" + var.from_hu_conv[1].replace("\n", "\n\t\t") + ";\n"
856             else:
857                 out_java_trait = out_java_trait + "\t\tthis.ptrs_to.add(" + var[1] + ");\n"
858         out_java_trait = out_java_trait + "\t\tthis.bindings_instance = arg;\n"
859         out_java_trait = out_java_trait + "\t}\n"
860         out_java_trait = out_java_trait + "\t@Override @SuppressWarnings(\"deprecation\")\n"
861         out_java_trait = out_java_trait + "\tprotected void finalize() throws Throwable {\n"
862         out_java_trait = out_java_trait + "\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); } super.finalize();\n"
863         out_java_trait = out_java_trait + "\t}\n\n"
864
865         java_trait_constr = "\tprivate static class " + struct_name + "Holder { " + struct_name.replace("LDK", "") + " held; }\n"
866         java_trait_constr = java_trait_constr + "\tpublic static " + struct_name.replace("LDK", "") + " new_impl(" + struct_name.replace("LDK", "") + "Interface arg"
867         for var in flattened_field_vars:
868             if isinstance(var, ConvInfo):
869                 java_trait_constr = java_trait_constr + ", " + var.java_hu_ty + " " + var.arg_name
870             else:
871                 # Ideally we'd be able to take any instance of the interface, but our C code can only represent
872                 # Java-implemented version, so we require users pass a Java implementation here :/
873                 java_trait_constr = java_trait_constr + ", " + var[0].replace("LDK", "") + "." + var[0].replace("LDK", "") + "Interface " + var[1] + "_impl"
874         java_trait_constr = java_trait_constr + ") {\n\t\tfinal " + struct_name + "Holder impl_holder = new " + struct_name + "Holder();\n"
875         java_trait_constr = java_trait_constr + "\t\timpl_holder.held = new " + struct_name.replace("LDK", "") + "(new bindings." + struct_name + "() {\n"
876         out_java_trait = out_java_trait + "\tpublic static interface " + struct_name.replace("LDK", "") + "Interface {\n"
877         out_java = out_java + "\tpublic interface " + struct_name + " {\n"
878         java_meths = []
879         for fn_line in field_fns:
880             java_meth_descr = "("
881             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
882                 out_java = out_java + "\t\t " + fn_line.ret_ty_info.java_ty + " " + fn_line.fn_name + "("
883                 java_trait_constr = java_trait_constr + "\t\t\t@Override public " + fn_line.ret_ty_info.java_ty + " " + fn_line.fn_name + "("
884                 out_java_trait += "\t\t/**\n\t\t * " + fn_line.docs.replace("\n", "\n\t\t * ") + "\n\t\t */\n"
885                 out_java_trait = out_java_trait + "\t\t" + fn_line.ret_ty_info.java_hu_ty + " " + fn_line.fn_name + "("
886
887                 for idx, arg_conv_info in enumerate(fn_line.args_ty):
888                     if idx >= 1:
889                         out_java = out_java + ", "
890                         java_trait_constr = java_trait_constr + ", "
891                         out_java_trait = out_java_trait + ", "
892                     out_java = out_java + arg_conv_info.java_ty + " " + arg_conv_info.arg_name
893                     out_java_trait = out_java_trait + arg_conv_info.java_hu_ty + " " + arg_conv_info.arg_name
894                     java_trait_constr = java_trait_constr + arg_conv_info.java_ty + " " + arg_conv_info.arg_name
895                     java_meth_descr = java_meth_descr + arg_conv_info.java_fn_ty_arg
896                 java_meth_descr = java_meth_descr + ")" + fn_line.ret_ty_info.java_fn_ty_arg
897                 java_meths.append((fn_line.fn_name, java_meth_descr))
898
899                 out_java = out_java + ");\n"
900                 out_java_trait = out_java_trait + ");\n"
901                 java_trait_constr = java_trait_constr + ") {\n"
902
903                 for arg_info in fn_line.args_ty:
904                     if arg_info.to_hu_conv is not None:
905                         java_trait_constr = java_trait_constr + "\t\t\t\t" + arg_info.to_hu_conv.replace("\n", "\n\t\t\t\t") + "\n"
906
907                 if fn_line.ret_ty_info.java_ty != "void":
908                     java_trait_constr = java_trait_constr + "\t\t\t\t" + fn_line.ret_ty_info.java_hu_ty + " ret = arg." + fn_line.fn_name + "("
909                 else:
910                     java_trait_constr = java_trait_constr + "\t\t\t\targ." + fn_line.fn_name + "("
911
912                 for idx, arg_info in enumerate(fn_line.args_ty):
913                     if idx != 0:
914                         java_trait_constr = java_trait_constr + ", "
915                     if arg_info.to_hu_conv_name is not None:
916                         java_trait_constr = java_trait_constr + arg_info.to_hu_conv_name
917                     else:
918                         java_trait_constr = java_trait_constr + arg_info.arg_name
919
920                 java_trait_constr += ");\n"
921                 java_trait_constr += "\t\t\t\tReference.reachabilityFence(arg);\n"
922                 if fn_line.ret_ty_info.java_ty != "void":
923                     if fn_line.ret_ty_info.from_hu_conv is not None:
924                         java_trait_constr = java_trait_constr + "\t\t\t\t" + fn_line.ret_ty_info.java_ty + " result = " + fn_line.ret_ty_info.from_hu_conv[0] + ";\n"
925                         if fn_line.ret_ty_info.from_hu_conv[1] != "":
926                             java_trait_constr = java_trait_constr + "\t\t\t\t" + fn_line.ret_ty_info.from_hu_conv[1].replace("this", "impl_holder.held") + ";\n"
927                         #if fn_line.ret_ty_info.rust_obj in result_types:
928                         java_trait_constr = java_trait_constr + "\t\t\t\treturn result;\n"
929                     else:
930                         java_trait_constr = java_trait_constr + "\t\t\t\treturn ret;\n"
931                 java_trait_constr = java_trait_constr + "\t\t\t}\n"
932         java_trait_constr = java_trait_constr + "\t\t}"
933         for var in field_vars:
934             if isinstance(var, ConvInfo):
935                 java_trait_constr = java_trait_constr + ", " + var.arg_name
936             else:
937                 java_trait_constr += ", " + var[1] + ".new_impl(" + var[1] + "_impl"
938                 for suparg in var[2]:
939                     if isinstance(suparg, ConvInfo):
940                         java_trait_constr += ", " + suparg.arg_name
941                     else:
942                         java_trait_constr += ", " + suparg[1]
943                 java_trait_constr += ").bindings_instance"
944                 for suparg in var[2]:
945                     if isinstance(suparg, ConvInfo):
946                         java_trait_constr += ", " + suparg.arg_name
947                     else:
948                         java_trait_constr += ", " + suparg[1]
949         out_java_trait = out_java_trait + "\t}\n"
950         out_java_trait = out_java_trait + java_trait_constr + ");\n\t\treturn impl_holder.held;\n\t}\n"
951
952         out_java = out_java + "\t}\n"
953
954         out_java = out_java + "\tpublic static native long " + struct_name + "_new(" + struct_name + " impl"
955         for var in flattened_field_vars:
956             if isinstance(var, ConvInfo):
957                 out_java = out_java + ", " + var.java_ty + " " + var.arg_name
958             else:
959                 out_java = out_java + ", " + var[0] + " " + var[1]
960         out_java = out_java + ");\n"
961
962         # Now that we've written out our java code (and created java_meths), generate C
963         out_c = "typedef struct " + struct_name + "_JCalls {\n"
964         out_c = out_c + "\tatomic_size_t refcnt;\n"
965         out_c = out_c + "\tJavaVM *vm;\n"
966         out_c = out_c + "\tjweak o;\n"
967         for var in flattened_field_vars:
968             if isinstance(var, ConvInfo):
969                 # We're a regular ol' field
970                 pass
971             else:
972                 # We're a supertrait
973                 out_c = out_c + "\t" + var[0] + "_JCalls* " + var[1] + ";\n"
974         for fn in field_fns:
975             if fn.fn_name != "free" and fn.fn_name != "cloned":
976                 out_c = out_c + "\tjmethodID " + fn.fn_name + "_meth;\n"
977         out_c = out_c + "} " + struct_name + "_JCalls;\n"
978
979         for fn_line in field_fns:
980             if fn_line.fn_name == "free":
981                 out_c = out_c + "static void " + struct_name + "_JCalls_free(void* this_arg) {\n"
982                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
983                 out_c = out_c + "\tif (atomic_fetch_sub_explicit(&j_calls->refcnt, 1, memory_order_acquire) == 1) {\n"
984                 out_c += "\t\t" + self.construct_jenv().replace("\n", "\n\t\t").strip() + "\n"
985                 out_c = out_c + "\t\t(*env)->DeleteWeakGlobalRef(env, j_calls->o);\n"
986                 out_c += "\t\t" + self.deconstruct_jenv().replace("\n", "\n\t\t").strip() + "\n"
987                 out_c = out_c + "\t\tFREE(j_calls);\n"
988                 out_c = out_c + "\t}\n}\n"
989
990         for idx, fn_line in enumerate(field_fns):
991             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
992                 assert fn_line.ret_ty_info.ty_info.get_full_rust_ty()[1] == ""
993                 out_c = out_c + fn_line.ret_ty_info.ty_info.get_full_rust_ty()[0] + " " + fn_line.fn_name + "_" + struct_name + "_jcall("
994                 if fn_line.self_is_const:
995                     out_c = out_c + "const void* this_arg"
996                 else:
997                     out_c = out_c + "void* this_arg"
998
999                 for idx, arg in enumerate(fn_line.args_ty):
1000                     out_c = out_c + ", " + arg.ty_info.get_full_rust_ty()[0] + " " + arg.arg_name + arg.ty_info.get_full_rust_ty()[1]
1001
1002                 out_c = out_c + ") {\n"
1003                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
1004                 out_c += "\t" + self.construct_jenv().replace("\n", "\n\t").strip() + "\n"
1005
1006                 for arg_info in fn_line.args_ty:
1007                     if arg_info.ret_conv is not None:
1008                         out_c = out_c + "\t" + arg_info.ret_conv[0].replace('\n', '\n\t')
1009                         out_c = out_c + arg_info.arg_name
1010                         out_c = out_c + arg_info.ret_conv[1].replace('\n', '\n\t') + "\n"
1011
1012                 out_c = out_c + "\tjobject obj = (*env)->NewLocalRef(env, j_calls->o);\n\tCHECK(obj != NULL);\n"
1013                 if fn_line.ret_ty_info.c_ty.endswith("Array"):
1014                     out_c = out_c + "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->CallObjectMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
1015                 elif fn_line.ret_ty_info.c_ty == "void":
1016                     out_c += "\t(*env)->CallVoidMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
1017                 elif fn_line.ret_ty_info.java_hu_ty == "String" or "org/ldk/enums" in fn_line.ret_ty_info.java_fn_ty_arg:
1018                     # Manually write out String methods as they're just an Object
1019                     out_c += "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->CallObjectMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
1020                 elif not fn_line.ret_ty_info.passed_as_ptr:
1021                     out_c += "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->Call" + fn_line.ret_ty_info.java_ty.title() + "Method(env, obj, j_calls->" + fn_line.fn_name + "_meth"
1022                 else:
1023                     out_c = out_c + "\tuint64_t ret = (*env)->CallLongMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
1024
1025                 for idx, arg_info in enumerate(fn_line.args_ty):
1026                     if arg_info.ret_conv is not None:
1027                         out_c = out_c + ", " + arg_info.ret_conv_name
1028                     else:
1029                         out_c = out_c + ", " + arg_info.arg_name
1030                 out_c = out_c + ");\n"
1031
1032                 out_c += "\tif (UNLIKELY((*env)->ExceptionCheck(env))) {\n"
1033                 out_c += "\t\t(*env)->ExceptionDescribe(env);\n"
1034                 out_c += "\t\t(*env)->FatalError(env, \"A call to " + fn_line.fn_name + " in " + struct_name + " from rust threw an exception.\");\n"
1035                 out_c += "\t}\n"
1036
1037                 if fn_line.ret_ty_info.arg_conv is not None:
1038                     out_c += "\t" + fn_line.ret_ty_info.arg_conv.replace("\n", "\n\t") + "\n"
1039                     out_c += "\t" + self.deconstruct_jenv().replace("\n", "\n\t").strip() + "\n"
1040                     out_c += "\treturn " + fn_line.ret_ty_info.arg_conv_name + ";\n"
1041                 else:
1042                     out_c += "\t" + self.deconstruct_jenv().replace("\n", "\n\t").strip() + "\n"
1043                     if not fn_line.ret_ty_info.passed_as_ptr and fn_line.ret_ty_info.c_ty != "void":
1044                         out_c += "\treturn ret;\n"
1045
1046                 out_c = out_c + "}\n"
1047
1048         # If we can, write out a clone function whether we need one or not, as we use them in moving to rust
1049         can_clone_with_ptr = True
1050         for var in field_vars:
1051             if isinstance(var, ConvInfo):
1052                 can_clone_with_ptr = False
1053         if can_clone_with_ptr:
1054             out_c = out_c + "static void " + struct_name + "_JCalls_cloned(" + struct_name + "* new_obj) {\n"
1055             out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) new_obj->this_arg;\n"
1056             out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->refcnt, 1, memory_order_release);\n"
1057             for var in field_vars:
1058                 if not isinstance(var, ConvInfo):
1059                     out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->" + var[1] + "->refcnt, 1, memory_order_release);\n"
1060             out_c = out_c + "}\n"
1061
1062         out_c = out_c + "static inline " + struct_name + " " + struct_name + "_init (" + self.c_fn_args_pfx + ", jobject o"
1063         for var in flattened_field_vars:
1064             if isinstance(var, ConvInfo):
1065                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
1066             else:
1067                 out_c = out_c + ", jobject " + var[1]
1068         out_c = out_c + ") {\n"
1069
1070         out_c = out_c + "\tjclass c = (*env)->GetObjectClass(env, o);\n"
1071         out_c = out_c + "\tCHECK(c != NULL);\n"
1072         out_c = out_c + "\t" + struct_name + "_JCalls *calls = MALLOC(sizeof(" + struct_name + "_JCalls), \"" + struct_name + "_JCalls\");\n"
1073         out_c = out_c + "\tatomic_init(&calls->refcnt, 1);\n"
1074         out_c = out_c + "\tDO_ASSERT((*env)->GetJavaVM(env, &calls->vm) == 0);\n"
1075         out_c = out_c + "\tcalls->o = (*env)->NewWeakGlobalRef(env, o);\n"
1076
1077         for (fn_name, java_meth_descr) in java_meths:
1078             if fn_name != "free" and fn_name != "cloned":
1079                 out_c = out_c + "\tcalls->" + fn_name + "_meth = (*env)->GetMethodID(env, c, \"" + fn_name + "\", \"" + java_meth_descr + "\");\n"
1080                 out_c = out_c + "\tCHECK(calls->" + fn_name + "_meth != NULL);\n"
1081
1082         for var in flattened_field_vars:
1083             if isinstance(var, ConvInfo) and var.arg_conv is not None:
1084                 out_c = out_c + "\n\t" + var.arg_conv.replace("\n", "\n\t") +"\n"
1085         out_c = out_c + "\n\t" + struct_name + " ret = {\n"
1086         out_c = out_c + "\t\t.this_arg = (void*) calls,\n"
1087         for fn_line in field_fns:
1088             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
1089                 out_c = out_c + "\t\t." + fn_line.fn_name + " = " + fn_line.fn_name + "_" + struct_name + "_jcall,\n"
1090             elif fn_line.fn_name == "free":
1091                 out_c = out_c + "\t\t.free = " + struct_name + "_JCalls_free,\n"
1092             else:
1093                 out_c = out_c + "\t\t.cloned = " + struct_name + "_JCalls_cloned,\n"
1094         for var in field_vars:
1095             if isinstance(var, ConvInfo):
1096                 if var.arg_conv_name is not None:
1097                     out_c = out_c + "\t\t." + var.arg_name + " = " + var.arg_conv_name + ",\n"
1098                     out_c = out_c + "\t\t.set_" + var.arg_name + " = NULL,\n"
1099                 else:
1100                     out_c = out_c + "\t\t." + var.var_name + " = " + var.var_name + ",\n"
1101                     out_c = out_c + "\t\t.set_" + var.var_name + " = NULL,\n"
1102             else:
1103                 out_c += "\t\t." + var[1] + " = " + var[0] + "_init(env, clz, " + var[1]
1104                 for suparg in var[2]:
1105                     if isinstance(suparg, ConvInfo):
1106                         out_c = out_c + ", " + suparg.arg_name
1107                     else:
1108                         out_c = out_c + ", " + suparg[1]
1109                 out_c += "),\n"
1110         out_c = out_c + "\t};\n"
1111         for var in flattened_field_vars:
1112             if not isinstance(var, ConvInfo):
1113                 out_c = out_c + "\tcalls->" + var[1] + " = ret." + var[1] + ".this_arg;\n"
1114         out_c = out_c + "\treturn ret;\n"
1115         out_c = out_c + "}\n"
1116
1117         out_c = out_c + self.c_fn_ty_pfx + "int64_t " + self.c_fn_name_define_pfx(struct_name + "_new", True) + "jobject o"
1118         for var in flattened_field_vars:
1119             if isinstance(var, ConvInfo):
1120                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
1121             else:
1122                 out_c = out_c + ", jobject " + var[1]
1123         out_c = out_c + ") {\n"
1124         out_c = out_c + "\t" + struct_name + " *res_ptr = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n"
1125         out_c = out_c + "\t*res_ptr = " + struct_name + "_init(env, clz, o"
1126         for var in flattened_field_vars:
1127             if isinstance(var, ConvInfo):
1128                 out_c = out_c + ", " + var.arg_name
1129             else:
1130                 out_c = out_c + ", " + var[1]
1131         out_c = out_c + ");\n"
1132         out_c = out_c + "\treturn tag_ptr(res_ptr, true);\n"
1133         out_c = out_c + "}\n"
1134
1135         for var in flattened_field_vars:
1136             if not isinstance(var, ConvInfo):
1137                 out_java_trait += "\n\t/**\n"
1138                 out_java_trait += "\t * Gets the underlying " + var[1] + ".\n"
1139                 out_java_trait += "\t */\n"
1140                 underscore_name = ''.join('_' + c.lower() if c.isupper() else c for c in var[1]).strip('_')
1141                 out_java_trait += "\tpublic " + var[1] + " get_" + underscore_name + "() {\n"
1142                 out_java_trait += "\t\t" + var[1] + " res = new " + var[1] + "(null, bindings." + struct_name + "_get_" + var[1] + "(this.ptr));\n"
1143                 out_java_trait += "\t\tthis.ptrs_to.add(res);\n"
1144                 out_java_trait += "\t\treturn res;\n"
1145                 out_java_trait += "\t}\n"
1146                 out_java_trait += "\n"
1147
1148                 out_java += "\tpublic static native long " + struct_name + "_get_" + var[1] + "(long arg);\n"
1149
1150                 out_c += "JNIEXPORT int64_t JNICALL Java_org_ldk_impl_bindings_" + struct_name + "_1get_1" + var[1] + "(JNIEnv *env, jclass clz, int64_t arg) {\n"
1151                 out_c += "\t" + struct_name + " *inp = (" + struct_name + " *)untag_ptr(arg);\n"
1152                 out_c += "\treturn tag_ptr(&inp->" + var[1] + ", false);\n"
1153                 out_c += "}\n"
1154
1155         return (out_java, out_java_trait, out_c)
1156
1157     def trait_struct_inc_refcnt(self, ty_info):
1158         base_conv = "\nif (" + ty_info.var_name + "_conv.free == " + ty_info.rust_obj + "_JCalls_free) {\n"
1159         base_conv = base_conv + "\t// If this_arg is a JCalls struct, then we need to increment the refcnt in it.\n"
1160         base_conv = base_conv + "\t" + ty_info.rust_obj + "_JCalls_cloned(&" + ty_info.var_name + "_conv);\n}"
1161         return base_conv
1162
1163     def map_complex_enum(self, struct_name, variant_list, camel_to_snake, enum_doc_comment):
1164         java_hu_type = struct_name.replace("LDK", "").replace("COption", "Option")
1165         out_java_enum = ""
1166         out_java = ""
1167         out_c = ""
1168
1169         out_java_enum += (self.hu_struct_file_prefix)
1170         out_java_enum += "\n/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
1171         out_java_enum += "@SuppressWarnings(\"unchecked\") // We correctly assign various generic arrays\n"
1172         out_java_enum += ("public class " + java_hu_type + " extends CommonBase {\n")
1173         out_java_enum += ("\tprivate " + java_hu_type + "(Object _dummy, long ptr) { super(ptr); }\n")
1174         out_java_enum += ("\t@Override @SuppressWarnings(\"deprecation\")\n")
1175         out_java_enum += ("\tprotected void finalize() throws Throwable {\n")
1176         out_java_enum += ("\t\tsuper.finalize();\n")
1177         out_java_enum += ("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK", "") + "_free(ptr); }\n")
1178         out_java_enum += ("\t}\n")
1179         out_java_enum += ("\tstatic " + java_hu_type + " constr_from_ptr(long ptr) {\n")
1180         out_java_enum += ("\t\tbindings." + struct_name + " raw_val = bindings." + struct_name + "_ref_from_ptr(ptr);\n")
1181         java_hu_subclasses = ""
1182
1183         init_meth_jty_strs = {}
1184
1185         out_java +=  ("\tpublic static class " + struct_name + " {\n")
1186         out_java +=  ("\t\tprivate " + struct_name + "() {}\n")
1187         for var in variant_list:
1188             out_java +=  ("\t\tpublic final static class " + var.var_name + " extends " + struct_name + " {\n")
1189             if var.var_docs is not None:
1190                 java_hu_subclasses += "\t/**\n\t * " + var.var_docs.replace("\n", "\n\t * ") + "\n\t */\n"
1191             java_hu_subclasses += "\tpublic final static class " + var.var_name + " extends " + java_hu_type + " {\n"
1192             out_java_enum += ("\t\tif (raw_val.getClass() == bindings." + struct_name + "." + var.var_name + ".class) {\n")
1193             out_java_enum += ("\t\t\treturn new " + var.var_name + "(ptr, (bindings." + struct_name + "." + var.var_name + ")raw_val);\n")
1194             init_meth_jty_str = ""
1195             init_meth_params = ""
1196             init_meth_body = ""
1197             hu_conv_body = ""
1198             for idx, (field_ty, field_docs) in enumerate(var.fields):
1199                 if idx > 0:
1200                     init_meth_params = init_meth_params + ", "
1201
1202                 java_ty = field_ty.java_ty
1203                 if field_ty.java_fn_ty_arg.startswith("L") and field_ty.java_fn_ty_arg.endswith(";"):
1204                     # If this is a simple enum, we have to reference it in the low-level bindings differently:
1205                     java_ty = field_ty.java_fn_ty_arg.strip("L;").replace("/", ".")
1206                 out_java += "\t\t\tpublic " + java_ty + " " + field_ty.arg_name + ";\n"
1207                 if field_docs is not None:
1208                     java_hu_subclasses += "\t\t/**\n\t\t * " + field_docs.replace("\n", "\n\t\t * ") + "\n\t\t*/\n"
1209                 java_hu_subclasses += "\t\t"
1210                 if field_ty.nullable:
1211                     java_hu_subclasses += "@Nullable "
1212                 java_hu_subclasses += "public final " + self.fully_qualified_hu_ty_path(field_ty) + " " + field_ty.arg_name + ";\n"
1213                 init_meth_params = init_meth_params + java_ty + " " + field_ty.arg_name
1214
1215                 init_meth_body = init_meth_body + "this." + field_ty.arg_name + " = " + field_ty.arg_name + "; "
1216                 if field_ty.to_hu_conv is not None:
1217                     hu_conv_body = hu_conv_body + "\t\t\t" + field_ty.java_ty + " " + field_ty.arg_name + " = obj." + field_ty.arg_name + ";\n"
1218                     hu_conv_body = hu_conv_body + "\t\t\t" + field_ty.to_hu_conv.replace("\n", "\n\t\t\t") + "\n"
1219                     hu_conv_body = hu_conv_body + "\t\t\tthis." + field_ty.arg_name + " = " + field_ty.to_hu_conv_name + ";\n"
1220                 else:
1221                     hu_conv_body = hu_conv_body + "\t\t\tthis." + field_ty.arg_name + " = obj." + field_ty.arg_name + ";\n"
1222                 init_meth_jty_str = init_meth_jty_str + field_ty.java_fn_ty_arg
1223             out_java +=  ("\t\t\t" + var.var_name + "(" + init_meth_params + ") { ")
1224             out_java +=  (init_meth_body)
1225             out_java +=  ("}\n")
1226             out_java += ("\t\t}\n")
1227             out_java_enum += ("\t\t}\n")
1228             java_hu_subclasses = java_hu_subclasses + "\t\tprivate " + var.var_name + "(long ptr, bindings." + struct_name + "." + var.var_name + " obj) {\n\t\t\tsuper(null, ptr);\n"
1229             java_hu_subclasses = java_hu_subclasses + hu_conv_body
1230             java_hu_subclasses = java_hu_subclasses + "\t\t}\n\t}\n"
1231             init_meth_jty_strs[var.var_name] = init_meth_jty_str
1232         out_java += ("\t\tstatic native void init();\n")
1233         out_java += ("\t}\n")
1234         out_java_enum += ("\t\tassert false; return null; // Unreachable without extending the (internal) bindings interface\n\t}\n\n")
1235         out_java_enum += (java_hu_subclasses)
1236         out_java += ("\tstatic { " + struct_name + ".init(); }\n")
1237         out_java += ("\tpublic static native " + struct_name + " " + struct_name + "_ref_from_ptr(long ptr);\n");
1238
1239         out_c += (self.c_complex_enum_pfx(struct_name, [x.var_name for x in variant_list], init_meth_jty_strs))
1240
1241         out_c += (self.c_fn_ty_pfx + self.c_complex_enum_pass_ty(struct_name) + " " + self.c_fn_name_define_pfx(struct_name + "_ref_from_ptr", True) + self.ptr_c_ty + " ptr) {\n")
1242         out_c += ("\t" + struct_name + " *obj = (" + struct_name + "*)untag_ptr(ptr);\n")
1243         out_c += ("\tswitch(obj->tag) {\n")
1244         for var in variant_list:
1245             out_c += ("\t\tcase " + struct_name + "_" + var.var_name + ": {\n")
1246             c_params = []
1247             for idx, (field_map, field_docs) in enumerate(var.fields):
1248                 if field_map.ret_conv is not None:
1249                     out_c += ("\t\t\t" + field_map.ret_conv[0].replace("\n", "\n\t\t\t"))
1250                     if var.tuple_variant:
1251                         out_c += "obj->" + camel_to_snake(var.var_name)
1252                     else:
1253                         out_c += "obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name
1254                     out_c += (field_map.ret_conv[1].replace("\n", "\n\t\t\t") + "\n")
1255                     c_params.append(field_map.ret_conv_name)
1256                 else:
1257                     if var.tuple_variant:
1258                         c_params.append("obj->" + camel_to_snake(var.var_name))
1259                     else:
1260                         c_params.append("obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name)
1261             out_c += ("\t\t\treturn " + self.c_constr_native_complex_enum(struct_name, var.var_name, c_params) + ";\n")
1262             out_c += ("\t\t}\n")
1263         out_c += ("\t\tdefault: abort();\n")
1264         out_c += ("\t}\n}\n")
1265         return (out_java, out_java_enum, out_c)
1266
1267     def map_opaque_struct(self, struct_name, struct_doc_comment):
1268         out_opaque_struct_human = ""
1269         out_opaque_struct_human += self.hu_struct_file_prefix
1270         out_opaque_struct_human += "\n/**\n * " + struct_doc_comment.replace("\n", "\n * ") + "\n */\n"
1271         out_opaque_struct_human += "@SuppressWarnings(\"unchecked\") // We correctly assign various generic arrays\n"
1272         hu_name = struct_name.replace("LDKC2Tuple", "TwoTuple").replace("LDKC3Tuple", "ThreeTuple").replace("LDK", "")
1273         out_opaque_struct_human += ("public class " + hu_name + " extends CommonBase")
1274         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1275             out_opaque_struct_human += (" implements AutoCloseable")
1276         out_opaque_struct_human += (" {\n")
1277         out_opaque_struct_human += ("\t" + hu_name + "(Object _dummy, long ptr) { super(ptr); }\n")
1278         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1279             out_opaque_struct_human += ("\t@Override public void close() {\n")
1280         else:
1281             out_opaque_struct_human += ("\t@Override @SuppressWarnings(\"deprecation\")\n")
1282             out_opaque_struct_human += ("\tprotected void finalize() throws Throwable {\n")
1283             out_opaque_struct_human += ("\t\tsuper.finalize();\n")
1284         out_opaque_struct_human += ("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); }\n")
1285         out_opaque_struct_human += ("\t}\n\n")
1286         return out_opaque_struct_human
1287
1288     def map_tuple(self, struct_name):
1289         return self.map_opaque_struct(struct_name, "A Tuple")
1290
1291     def map_result(self, struct_name, res_map, err_map):
1292         human_ty = struct_name.replace("LDKCResult", "Result")
1293         java_hu_struct = ""
1294         java_hu_struct += self.hu_struct_file_prefix
1295         java_hu_struct += "public class " + human_ty + " extends CommonBase {\n"
1296         java_hu_struct += "\tprivate " + human_ty + "(Object _dummy, long ptr) { super(ptr); }\n"
1297         java_hu_struct += "\tprotected void finalize() throws Throwable {\n"
1298         java_hu_struct += "\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); } super.finalize();\n"
1299         java_hu_struct += "\t}\n\n"
1300         java_hu_struct += "\tstatic " + human_ty + " constr_from_ptr(long ptr) {\n"
1301         java_hu_struct += "\t\tif (bindings." + struct_name.replace("LDK", "") + "_is_ok(ptr)) {\n"
1302         java_hu_struct += "\t\t\treturn new " + human_ty + "_OK(null, ptr);\n"
1303         java_hu_struct += "\t\t} else {\n"
1304         java_hu_struct += "\t\t\treturn new " + human_ty + "_Err(null, ptr);\n"
1305         java_hu_struct += "\t\t}\n"
1306         java_hu_struct += "\t}\n"
1307
1308         java_hu_struct += "\tpublic static final class " + human_ty + "_OK extends " + human_ty + " {\n"
1309
1310         if res_map.java_hu_ty != "void":
1311             java_hu_struct += "\t\tpublic final " + res_map.java_hu_ty + " res;\n"
1312         java_hu_struct += "\t\tprivate " + human_ty + "_OK(Object _dummy, long ptr) {\n"
1313         java_hu_struct += "\t\t\tsuper(_dummy, ptr);\n"
1314         if res_map.java_hu_ty == "void":
1315             pass
1316         elif res_map.to_hu_conv is not None:
1317             java_hu_struct += "\t\t\t" + res_map.java_ty + " res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1318             java_hu_struct += "\t\t\t" + res_map.to_hu_conv.replace("\n", "\n\t\t\t")
1319             java_hu_struct += "\n\t\t\tthis.res = " + res_map.to_hu_conv_name + ";\n"
1320         else:
1321             java_hu_struct += "\t\t\tthis.res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1322         java_hu_struct += "\t\t}\n"
1323         java_hu_struct += "\t}\n\n"
1324
1325         java_hu_struct += "\tpublic static final class " + human_ty + "_Err extends " + human_ty + " {\n"
1326         if err_map.java_hu_ty != "void":
1327             java_hu_struct += "\t\tpublic final " + err_map.java_hu_ty + " err;\n"
1328         java_hu_struct += "\t\tprivate " + human_ty + "_Err(Object _dummy, long ptr) {\n"
1329         java_hu_struct += "\t\t\tsuper(_dummy, ptr);\n"
1330         if err_map.java_hu_ty == "void":
1331             pass
1332         elif err_map.to_hu_conv is not None:
1333             java_hu_struct += "\t\t\t" + err_map.java_ty + " err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1334             java_hu_struct += "\t\t\t" + err_map.to_hu_conv.replace("\n", "\n\t\t\t")
1335             java_hu_struct += "\n\t\t\tthis.err = " + err_map.to_hu_conv_name + ";\n"
1336         else:
1337             java_hu_struct += "\t\t\tthis.err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1338         java_hu_struct += "\t\t}\n"
1339
1340         java_hu_struct += "\t}\n\n"
1341         return java_hu_struct
1342
1343     def map_function(self, argument_types, c_call_string, method_name, meth_n, return_type_info, struct_meth, default_constructor_args, takes_self, takes_self_as_ref, args_known, type_mapping_generator, doc_comment):
1344         out_java = ""
1345         out_c = ""
1346         out_java_struct = None
1347
1348         out_java += ("\tpublic static native ")
1349         out_c += (self.c_fn_ty_pfx)
1350         out_c += (return_type_info.c_ty)
1351         out_java += (return_type_info.java_ty)
1352         if return_type_info.ret_conv is not None:
1353             ret_conv_pfx, ret_conv_sfx = return_type_info.ret_conv
1354         out_java += (" " + method_name + "(")
1355         have_args = len(argument_types) > 1 or (len(argument_types) > 0 and argument_types[0].c_ty != "void")
1356         out_c += (" " + self.c_fn_name_define_pfx(method_name, have_args))
1357
1358         for idx, arg_conv_info in enumerate(argument_types):
1359             if idx != 0:
1360                 out_java += (", ")
1361                 out_c += (", ")
1362             if arg_conv_info.c_ty != "void":
1363                 out_c += (arg_conv_info.c_ty + " " + arg_conv_info.arg_name)
1364                 out_java += (arg_conv_info.java_ty + " " + arg_conv_info.arg_name)
1365
1366         out_java_struct = ""
1367         extra_java_struct_out = ""
1368         if not args_known:
1369             out_java_struct += ("\t// Skipped " + method_name + "\n")
1370         else:
1371             if doc_comment is not None:
1372                 out_java_struct += "\t/**\n\t * " + doc_comment.replace("\n", "\n\t * ") + "\n\t */\n"
1373             if return_type_info.nullable:
1374                 out_java_struct += "\t@Nullable\n"
1375             if not takes_self:
1376                 if meth_n == "new":
1377                     out_java_struct += "\tpublic static " + return_type_info.java_hu_ty + " of("
1378                 elif meth_n == "default":
1379                     out_java_struct += "\tpublic static " + return_type_info.java_hu_ty + " with_default("
1380                 else:
1381                     out_java_struct += "\tpublic static " + return_type_info.java_hu_ty + " " + meth_n + "("
1382             elif meth_n == "clone_ptr" or (struct_meth.startswith("LDKCResult") and (meth_n == "get_ok" or meth_n == "get_err")):
1383                 out_java_struct += ("\t" + return_type_info.java_hu_ty + " " + meth_n + "(")
1384             else:
1385                 if meth_n == "hash" and return_type_info.java_hu_ty == "long":
1386                     extra_java_struct_out = "\t@Override public int hashCode() {\n"
1387                     extra_java_struct_out += "\t\treturn (int)this.hash();\n"
1388                     extra_java_struct_out += "\t}\n"
1389                 elif meth_n == "eq" and return_type_info.java_hu_ty == "boolean":
1390                     extra_java_struct_out = "\t@Override public boolean equals(Object o) {\n"
1391                     extra_java_struct_out += "\t\tif (!(o instanceof " + struct_meth + ")) return false;\n"
1392                     extra_java_struct_out += "\t\treturn this.eq((" + struct_meth + ")o);\n"
1393                     extra_java_struct_out += "\t}\n"
1394                 out_java_struct += ("\tpublic " + return_type_info.java_hu_ty + " " + meth_n + "(")
1395             for idx, arg in enumerate(argument_types):
1396                 if idx != 0:
1397                     if not takes_self or idx > 1:
1398                         out_java_struct += ", "
1399                 elif takes_self:
1400                     continue
1401                 if arg.java_ty != "void":
1402                     if arg.arg_name in default_constructor_args:
1403                         assert not arg.nullable
1404                         for explode_idx, explode_arg in enumerate(default_constructor_args[arg.arg_name]):
1405                             if explode_idx != 0:
1406                                 out_java_struct += (", ")
1407                             out_java_struct += (
1408                                 explode_arg.java_hu_ty + " " + arg.arg_name + "_" + explode_arg.arg_name)
1409                     else:
1410                         if arg.nullable:
1411                             out_java_struct += "@Nullable "
1412                         ty_string = arg.java_hu_ty
1413                         if arg.java_fn_ty_arg[0] == "L" and arg.java_fn_ty_arg[len(arg.java_fn_ty_arg) - 1] == ";":
1414                             ty_string = arg.java_fn_ty_arg.strip("L;").replace("/", ".")
1415                         out_java_struct += ty_string + " " + arg.arg_name
1416         out_java += (");\n")
1417         out_c += (") {\n")
1418         if out_java_struct is not None:
1419             out_java_struct += (") {\n")
1420         for info in argument_types:
1421             if info.arg_conv is not None:
1422                 out_c += ("\t" + info.arg_conv.replace('\n', "\n\t") + "\n")
1423         if return_type_info.ret_conv is not None:
1424             out_c += ("\t" + ret_conv_pfx.replace('\n', '\n\t'))
1425         elif return_type_info.c_ty != "void":
1426             out_c += ("\t" + return_type_info.c_ty + " ret_val = ")
1427         else:
1428             out_c += ("\t")
1429         if c_call_string is None:
1430             out_c += (method_name + "(")
1431         else:
1432             out_c += (c_call_string)
1433         for idx, info in enumerate(argument_types):
1434             if info.arg_conv_name is not None:
1435                 if idx != 0:
1436                     out_c += (", ")
1437                 elif c_call_string is not None:
1438                     continue
1439                 out_c += (info.arg_conv_name)
1440         out_c += (")")
1441         if return_type_info.ret_conv is not None:
1442             out_c += (ret_conv_sfx.replace('\n', '\n\t'))
1443         else:
1444             out_c += (";")
1445         for info in argument_types:
1446             if info.arg_conv_cleanup is not None:
1447                 out_c += ("\n\t" + info.arg_conv_cleanup.replace("\n", "\n\t"))
1448         if return_type_info.ret_conv is not None:
1449             out_c += ("\n\treturn " + return_type_info.ret_conv_name + ";")
1450         elif return_type_info.c_ty != "void":
1451             out_c += ("\n\treturn ret_val;")
1452         out_c += ("\n}\n\n")
1453
1454         if args_known:
1455             out_java_struct += ("\t\t")
1456             if return_type_info.java_ty != "void":
1457                 out_java_struct += (return_type_info.java_ty + " ret = ")
1458             out_java_struct += ("bindings." + method_name + "(")
1459             for idx, info in enumerate(argument_types):
1460                 if idx != 0:
1461                     out_java_struct += (", ")
1462                 if idx == 0 and takes_self:
1463                     out_java_struct += ("this.ptr")
1464                 elif info.arg_name in default_constructor_args:
1465                     out_java_struct += ("bindings." + info.java_hu_ty + "_new(")
1466                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1467                         if explode_idx != 0:
1468                             out_java_struct += (", ")
1469                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1470                         if explode_arg.from_hu_conv is not None:
1471                             out_java_struct += (
1472                                 explode_arg.from_hu_conv[0].replace(explode_arg.arg_name, expl_arg_name))
1473                         else:
1474                             out_java_struct += (expl_arg_name)
1475                     out_java_struct += (")")
1476                 elif info.from_hu_conv is not None:
1477                     out_java_struct += (info.from_hu_conv[0])
1478                 else:
1479                     out_java_struct += (info.arg_name)
1480             out_java_struct += (");\n")
1481
1482             # This is completely nuts. The OpenJDK JRE JIT will optimize out a object which is on
1483             # the stack, calling its finalizer immediately even if member methods are *actively
1484             # executing* on the same object, as long as said object is on the stack. There is no
1485             # concrete specification for when the optimizer is allowed to do this, and when it is
1486             # not, so there is absolutely no way to be certain that this fix suffices.
1487             #
1488             # Instead, the "Java Language Specification" says only that an object is reachable
1489             # (i.e. will not yet be finalized) if it "can be accessed in any potential continuing
1490             # computation from any live thread". To any sensible reader this would mean actively
1491             # executing a member function on an object would make it not eligible for finalization.
1492             # But, no, dear reader, this statement does not say that. Well, okay, it says that,
1493             # very explicitly in fact, but those are just, like, words, man.
1494             #
1495             # In the seemingly non-normative text further down, a few examples of things the
1496             # optimizer can do are given, including "if the values in an object's fields are
1497             # stored in registers[, t]he may then access the registers instead of the object, and
1498             # never access the object again[, implying] that the object is garbage". This appears
1499             # to fully contradict both the above statement, the API documentation in java.lang.ref
1500             # regarding when a reference is "strongly reachable", and basic common sense. There is
1501             # no concrete set of limitations stated, however, seemingly implying the JIT could
1502             # decide your code would run faster by simply garbage collecting everything
1503             # immediately, ensuring your code finishes soon, just by SEGFAULT. Thus, we're really
1504             # entirely flying blind here. We add some fences and hope that its sufficient, but
1505             # with no specification to rely on, we cannot be certain of anything.
1506             #
1507             # TL;DR: The Java Language "Specification" provides no real guarantees on when an
1508             # object will be considered available for garbage collection once the JIT kicks in, so
1509             # we put in some fences and hope to god the JIT doesn't get smarter/more broken.
1510             for idx, info in enumerate(argument_types):
1511                 if idx == 0 and takes_self:
1512                     out_java_struct += ("\t\tReference.reachabilityFence(this);\n")
1513                 elif info.arg_name in default_constructor_args:
1514                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1515                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1516                         out_java_struct += ("\t\tReference.reachabilityFence(" + expl_arg_name + ");\n")
1517                 elif info.c_ty != "void":
1518                     out_java_struct += ("\t\tReference.reachabilityFence(" + info.arg_name + ");\n")
1519
1520             if return_type_info.java_ty == "long" and return_type_info.java_hu_ty != "long":
1521                 out_java_struct += "\t\tif (ret >= 0 && ret <= 4096) { return null; }\n"
1522
1523             if return_type_info.to_hu_conv is not None:
1524                 if not takes_self:
1525                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t").replace("this",
1526                                                                                                                return_type_info.to_hu_conv_name) + "\n")
1527                 else:
1528                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t") + "\n")
1529
1530             for idx, info in enumerate(argument_types):
1531                 if idx == 0 and takes_self:
1532                     pass
1533                 elif info.arg_name in default_constructor_args:
1534                     for explode_arg in default_constructor_args[info.arg_name]:
1535                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1536                         if explode_arg.from_hu_conv is not None and return_type_info.to_hu_conv_name:
1537                             out_java_struct += ("\t\t" + explode_arg.from_hu_conv[1].replace(explode_arg.arg_name,
1538                                                                                                expl_arg_name).replace(
1539                                 "this", return_type_info.to_hu_conv_name) + ";\n")
1540                 elif info.from_hu_conv is not None and info.from_hu_conv[1] != "":
1541                     if not takes_self and return_type_info.to_hu_conv_name is not None:
1542                         out_java_struct += (
1543                             "\t\t" + info.from_hu_conv[1].replace("this", return_type_info.to_hu_conv_name).replace("\n", "\n\t\t") + ";\n")
1544                     else:
1545                         out_java_struct += ("\t\t" + info.from_hu_conv[1].replace("\n", "\n\t\t") + ";\n")
1546
1547             if takes_self and not takes_self_as_ref:
1548                 out_java_struct += "\t\t" + argument_types[0].from_hu_conv[1].replace("\n", "\n\t\t").replace("this_arg", "this") + ";\n"
1549             if return_type_info.to_hu_conv_name is not None:
1550                 out_java_struct += ("\t\treturn " + return_type_info.to_hu_conv_name + ";\n")
1551             elif return_type_info.java_ty != "void" and return_type_info.rust_obj != "LDK" + struct_meth:
1552                 out_java_struct += ("\t\treturn ret;\n")
1553             out_java_struct += ("\t}\n\n")
1554
1555         return (out_java, out_c, out_java_struct + extra_java_struct_out)
1556
1557     def cleanup(self):
1558         pass