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