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