git.bitcoin.ninja 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     MACOS = 3
   9
  10 class Consts:
  11     def __init__(self, DEBUG: bool, target: Target, **kwargs):
  12         self.target = target
  13         self.c_array_class_caches = set()
  14         self.c_type_map = dict(
  15             bool = ['boolean'],
  16             uint8_t = ['byte'],
  17             uint16_t = ['short'],
  18             uint32_t = ['int'],
  19             uint64_t = ['long'],
  20             int64_t = ['long'],
  21         )
  22         self.java_type_map = dict(
  23             String = "String"
  24         )
  25         self.java_hu_type_map = dict(
  26             String = "String"
  27         )
  28
  29         self.to_hu_conv_templates = dict(
  30             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}); }',
  31             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}); }'
  32         )
  33
  34         self.bindings_header = """package org.ldk.impl;
  35 import org.ldk.enums.*;
  36 import org.ldk.impl.version;
  37 import java.io.File;
  38 import java.io.InputStream;
  39 import java.io.IOException;
  40 import java.nio.file.Files;
  41 import java.nio.file.Path;
  42 import java.nio.file.StandardCopyOption;
  43
  44 public class bindings {
  45         static {
  46                 try {
  47                         // Try to load natively first, this works on Android and in testing.
  48                         System.loadLibrary(\"lightningjni\");
  49                 } catch (UnsatisfiedLinkError system_load_err) {
  50                         // Otherwise try to load from the library jar.
  51                         File tmpdir = new File(System.getProperty("java.io.tmpdir"), "ldk-java-nativelib");
  52                         tmpdir.mkdir(); // If it fails to create, assume it was there already
  53                         tmpdir.deleteOnExit();
  54                         String libname = "liblightningjni_" + System.getProperty("os.name").replaceAll(" ", "") +
  55                                 "-" + System.getProperty("os.arch").replaceAll(" ", "") + ".nativelib";
  56                         try (InputStream is = bindings.class.getResourceAsStream("/" + libname)) {
  57                                 Path libpath = new File(tmpdir.toPath().toString(), "liblightningjni.so").toPath();
  58                                 Files.copy(is, libpath, StandardCopyOption.REPLACE_EXISTING);
  59                                 Runtime.getRuntime().load(libpath.toString());
  60                         } catch (Exception e) {
  61                                 System.err.println("Failed to load LDK native library.");
  62                                 System.err.println("System LDK native library load failed with: " + system_load_err);
  63                                 System.err.println("Resource-based LDK native library load failed with: " + e);
  64                                 throw new IllegalArgumentException(e);
  65                         }
  66                 }
  67                 init(java.lang.Enum.class);
  68                 init_class_cache();
  69                 if (!get_lib_version_string().equals(version.get_ldk_java_bindings_version()))
  70                         throw new IllegalArgumentException("Compiled LDK library and LDK class failes do not match");
  71                 // Fetching the LDK versions from C also checks that the header and binaries match
  72                 System.err.println("Loaded LDK-Java Bindings " + version.get_ldk_java_bindings_version() + " with LDK " + get_ldk_version() + " and LDK-C-Bindings " + get_ldk_c_bindings_version());
  73         }
  74         static native void init(java.lang.Class c);
  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 """
  82         self.bindings_version_file = """package org.ldk.impl;
  83
  84 public class version {
  85         public static String get_ldk_java_bindings_version() {
  86                 return "<git_version_ldk_garbagecollected>";
  87         }
  88 }"""
  89
  90         self.util_fn_pfx = """package org.ldk.structs;
  91 import org.ldk.impl.bindings;
  92 import org.ldk.enums.*;
  93 import org.ldk.util.*;
  94 import java.util.Arrays;
  95 import java.lang.ref.Reference;
  96 import javax.annotation.Nullable;
  97
  98 public class UtilMethods {
  99 """
 100         self.util_fn_sfx = "}"
 101         self.common_base = """package org.ldk.structs;
 102 import java.util.LinkedList;
 103 class CommonBase {
 104         long ptr;
 105         LinkedList<Object> ptrs_to = new LinkedList();
 106         protected CommonBase(long ptr) { assert ptr < 0 || ptr > 4096; this.ptr = ptr; }
 107 }
 108 """
 109
 110         self.txout_defn = """public class TxOut extends CommonBase {
 111         /** The script_pubkey in this output */
 112         public final byte[] script_pubkey;
 113         /** The value, in satoshis, of this output */
 114         public final long value;
 115
 116         TxOut(java.lang.Object _dummy, long ptr) {
 117                 super(ptr);
 118                 this.script_pubkey = bindings.TxOut_get_script_pubkey(ptr);
 119                 this.value = bindings.TxOut_get_value(ptr);
 120         }
 121         public TxOut(long value, byte[] script_pubkey) {
 122                 super(bindings.TxOut_new(script_pubkey, value));
 123                 this.script_pubkey = bindings.TxOut_get_script_pubkey(ptr);
 124                 this.value = bindings.TxOut_get_value(ptr);
 125         }
 126
 127         @Override @SuppressWarnings(\"deprecation\")
 128         protected void finalize() throws Throwable {
 129                 super.finalize();
 130                 if (ptr != 0) { bindings.TxOut_free(ptr); }
 131         }
 132 }"""
 133
 134         self.txin_defn = """public class TxIn extends CommonBase {
 135         /** The witness in this input, in serialized form */
 136         public final byte[] witness;
 137         /** The script_sig in this input */
 138         public final byte[] script_sig;
 139         /** The transaction output's sequence number */
 140         public final int sequence;
 141         /** The txid this input is spending */
 142         public final byte[] previous_txid;
 143         /** The output index within the spent transaction of the output this input is spending */
 144         public final int previous_vout;
 145
 146         TxIn(java.lang.Object _dummy, long ptr) {
 147                 super(ptr);
 148                 this.witness = bindings.TxIn_get_witness(ptr);
 149                 this.script_sig = bindings.TxIn_get_script_sig(ptr);
 150                 this.sequence = bindings.TxIn_get_sequence(ptr);
 151                 this.previous_txid = bindings.TxIn_get_previous_txid(ptr);
 152                 this.previous_vout = bindings.TxIn_get_previous_vout(ptr);
 153         }
 154         /** Constructs a new TxIn, note that previous_txid must be exactly 32 bytes */
 155         public TxIn(byte[] witness, byte[] script_sig, int sequence, byte[] previous_txid, int previous_vout) {
 156                 this(null, bindings.TxIn_new(witness, script_sig, sequence, previous_txid, previous_vout));
 157         }
 158
 159         @Override @SuppressWarnings(\"deprecation\")
 160         protected void finalize() throws Throwable {
 161                 super.finalize();
 162                 if (ptr != 0) { bindings.TxIn_free(ptr); }
 163         }
 164 }"""
 165
 166         self.scalar_defn = """public class BigEndianScalar extends CommonBase {
 167         /** The bytes of the scalar value, in big endian */
 168         public final byte[] scalar_bytes;
 169
 170         BigEndianScalar(java.lang.Object _dummy, long ptr) {
 171                 super(ptr);
 172                 this.scalar_bytes = bindings.BigEndianScalar_get_bytes(ptr);
 173         }
 174         public BigEndianScalar(byte[] scalar_bytes) {
 175                 super(bindings.BigEndianScalar_new(scalar_bytes));
 176                 this.scalar_bytes = bindings.BigEndianScalar_get_bytes(ptr);
 177         }
 178
 179         @Override @SuppressWarnings(\"deprecation\")
 180         protected void finalize() throws Throwable {
 181                 super.finalize();
 182                 if (ptr != 0) { bindings.BigEndianScalar_free(ptr); }
 183         }
 184 }"""
 185
 186
 187         self.c_file_pfx = """#include <jni.h>
 188 // On OSX jlong (ie long long) is not equivalent to int64_t, so we override here
 189 #define int64_t jlong
 190 #include \"org_ldk_impl_bindings.h\"
 191 #include <lightning.h>
 192 #include <string.h>
 193 #include <stdatomic.h>
 194 #include <stdlib.h>
 195
 196 #define LIKELY(v) __builtin_expect(!!(v), 1)
 197 #define UNLIKELY(v) __builtin_expect(!!(v), 0)
 198
 199 """
 200
 201         if self.target == Target.ANDROID:
 202             self.c_file_pfx = self.c_file_pfx + """
 203 #include <android/log.h>
 204 #define DEBUG_PRINT(...) __android_log_print(ANDROID_LOG_ERROR, "LDK", __VA_ARGS__)
 205
 206 #include <unistd.h>
 207 #include <pthread.h>
 208 static void* redirect_stderr(void* ignored) {
 209         int pipes[2];
 210         pipe(pipes);
 211         dup2(pipes[1], STDERR_FILENO);
 212         char buf[8192];
 213         memset(buf, 0, 8192);
 214         ssize_t len;
 215         while ((len = read(pipes[0], buf, 8191)) > 0) {
 216                 DEBUG_PRINT("%s\\n", buf);
 217                 memset(buf, 0, 8192);
 218         }
 219         DEBUG_PRINT("End of stderr???\\n");
 220         return 0;
 221 }
 222 void __attribute__((constructor)) spawn_stderr_redirection() {
 223         pthread_t thread;
 224         pthread_create(&thread, NULL, &redirect_stderr, NULL);
 225 }
 226 """
 227         else:
 228             self.c_file_pfx = self.c_file_pfx + "#define DEBUG_PRINT(...) fprintf(stderr, __VA_ARGS__)\n"
 229
 230         if not DEBUG or self.target == Target.MACOS:
 231             self.c_file_pfx = self.c_file_pfx + """#define MALLOC(a, _) malloc(a)
 232 #define FREE(p) if ((uint64_t)(p) > 4096) { free(p); }
 233 #define CHECK_ACCESS(p)
 234 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v)
 235 """
 236         if not DEBUG:
 237             self.c_file_pfx += """#define DO_ASSERT(a) (void)(a)
 238 #define CHECK(a)
 239 """
 240         if DEBUG:
 241             self.c_file_pfx = self.c_file_pfx + """#include <assert.h>
 242 // Always run a, then assert it is true:
 243 #define DO_ASSERT(a) do { bool _assert_val = (a); assert(_assert_val); } while(0)
 244 // Assert a is true or do nothing
 245 #define CHECK(a) DO_ASSERT(a)
 246
 247 void __attribute__((constructor)) debug_log_version() {
 248         if (check_get_ldk_version() == NULL)
 249                 DEBUG_PRINT("LDK version did not match the header we built against\\n");
 250         if (check_get_ldk_bindings_version() == NULL)
 251                 DEBUG_PRINT("LDK C Bindings version did not match the header we built against\\n");
 252 }
 253 """
 254
 255             if self.target != Target.MACOS:
 256                 self.c_file_pfx += """
 257 // Running a leak check across all the allocations and frees of the JDK is a mess,
 258 // so instead we implement our own naive leak checker here, relying on the -wrap
 259 // linker option to wrap malloc/calloc/realloc/free, tracking everyhing allocated
 260 // and free'd in Rust or C across the generated bindings shared library.
 261 #include <threads.h>
 262 """
 263
 264                 if self.target == Target.ANDROID:
 265                     self.c_file_pfx = self.c_file_pfx + """
 266 #include <unwind.h>
 267 #include <dlfcn.h>
 268
 269 // Implement the execinfo functions using _Unwind_backtrace. This seems to miss many Rust
 270 // symbols, so we only use it on Android, where execinfo.h is unavailable.
 271
 272 struct BacktraceState {
 273         void** current;
 274         void** end;
 275 };
 276 static _Unwind_Reason_Code unwind_callback(struct _Unwind_Context* context, void* arg) {
 277         struct BacktraceState* state = (struct BacktraceState*)arg;
 278         uintptr_t pc = _Unwind_GetIP(context);
 279         if (pc) {
 280                 if (state->current == state->end) {
 281                         return _URC_END_OF_STACK;
 282                 } else {
 283                         *state->current++ = (void*)(pc);
 284                 }
 285         }
 286         return _URC_NO_REASON;
 287 }
 288
 289 int backtrace(void** buffer, int max) {
 290         struct BacktraceState state = { buffer, buffer + max };
 291         _Unwind_Backtrace(unwind_callback, &state);
 292         return state.current - buffer;
 293 }
 294
 295 void backtrace_symbols_fd(void ** buffer, int count, int _fd) {
 296         for (int idx = 0; idx < count; ++idx) {
 297                 Dl_info info;
 298                 if (dladdr(buffer[idx], &info) && info.dli_sname) {
 299                         DEBUG_PRINT("%p: %s", buffer[idx], info.dli_sname);
 300                 } else {
 301                         DEBUG_PRINT("%p: ???", buffer[idx]);
 302                 }
 303         }
 304 }
 305 """
 306                 else:
 307                     self.c_file_pfx = self.c_file_pfx + "#include <execinfo.h>\n"
 308                 self.c_file_pfx = self.c_file_pfx + """
 309 #include <unistd.h>
 310 #include <pthread.h>
 311 static pthread_mutex_t allocation_mtx;
 312
 313 void __attribute__((constructor)) init_mtx() {
 314         DO_ASSERT(!pthread_mutex_init(&allocation_mtx, NULL));
 315 }
 316
 317 #define BT_MAX 128
 318 typedef struct allocation {
 319         struct allocation* next;
 320         void* ptr;
 321         const char* struct_name;
 322         void* bt[BT_MAX];
 323         int bt_len;
 324         unsigned long alloc_len;
 325 } allocation;
 326 static allocation* allocation_ll = NULL;
 327
 328 void* __real_malloc(size_t len);
 329 void* __real_calloc(size_t nmemb, size_t len);
 330 static void new_allocation(void* res, const char* struct_name, size_t len) {
 331         allocation* new_alloc = __real_malloc(sizeof(allocation));
 332         new_alloc->ptr = res;
 333         new_alloc->struct_name = struct_name;
 334         new_alloc->bt_len = backtrace(new_alloc->bt, BT_MAX);
 335         new_alloc->alloc_len = len;
 336         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 337         new_alloc->next = allocation_ll;
 338         allocation_ll = new_alloc;
 339         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 340 }
 341 static void* MALLOC(size_t len, const char* struct_name) {
 342         void* res = __real_malloc(len);
 343         new_allocation(res, struct_name, len);
 344         return res;
 345 }
 346 void __real_free(void* ptr);
 347 static void alloc_freed(void* ptr) {
 348         allocation* p = NULL;
 349         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 350         allocation* it = allocation_ll;
 351         while (it->ptr != ptr) {
 352                 p = it; it = it->next;
 353                 if (it == NULL) {
 354                         DEBUG_PRINT("ERROR: Tried to free unknown pointer %p at:\\n", ptr);
 355                         void* bt[BT_MAX];
 356                         int bt_len = backtrace(bt, BT_MAX);
 357                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
 358                         DEBUG_PRINT("\\n\\n");
 359                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 360                         return; // addrsan should catch malloc-unknown and print more info than we have
 361                 }
 362         }
 363         if (p) { p->next = it->next; } else { allocation_ll = it->next; }
 364         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 365         DO_ASSERT(it->ptr == ptr);
 366         __real_free(it);
 367 }
 368 static void FREE(void* ptr) {
 369         if ((uint64_t)ptr <= 4096) return; // Rust loves to create pointers to the NULL page for dummys
 370         alloc_freed(ptr);
 371         __real_free(ptr);
 372 }
 373
 374 void* __wrap_malloc(size_t len) {
 375         void* res = __real_malloc(len);
 376         new_allocation(res, "malloc call", len);
 377         return res;
 378 }
 379 void* __wrap_calloc(size_t nmemb, size_t len) {
 380         void* res = __real_calloc(nmemb, len);
 381         new_allocation(res, "calloc call", len);
 382         return res;
 383 }
 384 void __wrap_free(void* ptr) {
 385         if (ptr == NULL) return;
 386         alloc_freed(ptr);
 387         __real_free(ptr);
 388 }
 389
 390 static void CHECK_ACCESS(const void* ptr) {
 391         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 392         allocation* it = allocation_ll;
 393         while (it->ptr != ptr) {
 394                 it = it->next;
 395                 if (it == NULL) {
 396                         DEBUG_PRINT("ERROR: Tried to access unknown pointer %p at:\\n", ptr);
 397                         void* bt[BT_MAX];
 398                         int bt_len = backtrace(bt, BT_MAX);
 399                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
 400                         DEBUG_PRINT("\\n\\n");
 401                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 402                         return; // addrsan should catch and print more info than we have
 403                 }
 404         }
 405         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 406 }
 407 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v) \\
 408         if (v.is_owned && v.inner != NULL) { \\
 409                 const void *p = __unmangle_inner_ptr(v.inner); \\
 410                 if (p != NULL) { \\
 411                         CHECK_ACCESS(p); \\
 412                 } \\
 413         }
 414
 415 void* __real_realloc(void* ptr, size_t newlen);
 416 void* __wrap_realloc(void* ptr, size_t len) {
 417         if (ptr != NULL) alloc_freed(ptr);
 418         void* res = __real_realloc(ptr, len);
 419         new_allocation(res, "realloc call", len);
 420         return res;
 421 }
 422 void __wrap_reallocarray(void* ptr, size_t new_sz) {
 423         // Rust doesn't seem to use reallocarray currently
 424         DO_ASSERT(false);
 425 }
 426
 427 void __attribute__((destructor)) check_leaks() {
 428         unsigned long alloc_count = 0;
 429         unsigned long alloc_size = 0;
 430         DEBUG_PRINT("The following LDK-allocated blocks still remain.\\n");
 431         DEBUG_PRINT("Note that this is only accurate if System.gc(); System.runFinalization()\\n");
 432         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
 433         for (allocation* a = allocation_ll; a != NULL; a = a->next) {
 434                 DEBUG_PRINT("%s %p (%lu bytes) remains:\\n", a->struct_name, a->ptr, a->alloc_len);
 435                 backtrace_symbols_fd(a->bt, a->bt_len, STDERR_FILENO);
 436                 DEBUG_PRINT("\\n\\n");
 437                 alloc_count++;
 438                 alloc_size += a->alloc_len;
 439         }
 440         DEBUG_PRINT("%lu allocations remained for %lu bytes.\\n", alloc_count, alloc_size);
 441         DEBUG_PRINT("Note that this is only accurate if System.gc(); System.runFinalization()\\n");
 442         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
 443 }
 444 """
 445         self.c_file_pfx = self.c_file_pfx + """
 446 static jmethodID ordinal_meth = NULL;
 447 JNIEXPORT void Java_org_ldk_impl_bindings_init(JNIEnv * env, jclass _b, jclass enum_class) {
 448         ordinal_meth = (*env)->GetMethodID(env, enum_class, "ordinal", "()I");
 449         CHECK(ordinal_meth != NULL);
 450 }
 451
 452 // We assume that CVec_u8Z and u8slice are the same size and layout (and thus pointers to the two can be mixed)
 453 _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKu8slice), "Vec<u8> and [u8] need to have been mapped identically");
 454 _Static_assert(offsetof(LDKCVec_u8Z, data) == offsetof(LDKu8slice, data), "Vec<u8> and [u8] need to have been mapped identically");
 455 _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKu8slice, datalen), "Vec<u8> and [u8] need to have been mapped identically");
 456
 457 _Static_assert(sizeof(jlong) == sizeof(int64_t), "We assume that j-types are the same as C types");
 458 _Static_assert(sizeof(jbyte) == sizeof(char), "We assume that j-types are the same as C types");
 459 _Static_assert(sizeof(void*) <= 8, "Pointers must fit into 64 bits");
 460
 461 typedef jlongArray int64_tArray;
 462 typedef jbyteArray int8_tArray;
 463 typedef jshortArray int16_tArray;
 464
 465 static inline jstring str_ref_to_java(JNIEnv *env, const char* chars, size_t len) {
 466         // Sadly we need to create a temporary because Java can't accept a char* without a 0-terminator
 467         char* conv_buf = MALLOC(len + 1, "str conv buf");
 468         memcpy(conv_buf, chars, len);
 469         conv_buf[len] = 0;
 470         jstring ret = (*env)->NewStringUTF(env, conv_buf);
 471         FREE(conv_buf);
 472         return ret;
 473 }
 474 static inline LDKStr java_to_owned_str(JNIEnv *env, jstring str) {
 475         uint64_t str_len = (*env)->GetStringUTFLength(env, str);
 476         char* newchars = MALLOC(str_len + 1, "String chars");
 477         const char* jchars = (*env)->GetStringUTFChars(env, str, NULL);
 478         memcpy(newchars, jchars, str_len);
 479         newchars[str_len] = 0;
 480         (*env)->ReleaseStringUTFChars(env, str, jchars);
 481         LDKStr res = {
 482                 .chars = newchars,
 483                 .len = str_len,
 484                 .chars_is_owned = true
 485         };
 486         return res;
 487 }
 488
 489 JNIEXPORT jstring JNICALL Java_org_ldk_impl_bindings_get_1ldk_1c_1bindings_1version(JNIEnv *env, jclass _c) {
 490         return str_ref_to_java(env, check_get_ldk_bindings_version(), strlen(check_get_ldk_bindings_version()));
 491 }
 492 JNIEXPORT jstring JNICALL Java_org_ldk_impl_bindings_get_1ldk_1version(JNIEnv *env, jclass _c) {
 493         return str_ref_to_java(env, check_get_ldk_version(), strlen(check_get_ldk_version()));
 494 }
 495 #include "version.c"
 496 """
 497         self.c_version_file = """JNIEXPORT jstring JNICALL Java_org_ldk_impl_bindings_get_1lib_1version_1string(JNIEnv *env, jclass _c) {
 498         return str_ref_to_java(env, "<git_version_ldk_garbagecollected>", strlen("<git_version_ldk_garbagecollected>"));
 499 }"""
 500
 501         self.hu_struct_file_prefix = """package org.ldk.structs;
 502
 503 import org.ldk.impl.bindings;
 504 import org.ldk.enums.*;
 505 import org.ldk.util.*;
 506 import java.util.Arrays;
 507 import java.lang.ref.Reference;
 508 import javax.annotation.Nullable;
 509
 510 """
 511         self.hu_struct_file_suffix = ""
 512         self.c_fn_ty_pfx = "JNIEXPORT "
 513         self.c_fn_args_pfx = "JNIEnv *env, jclass clz"
 514         self.file_ext = ".java"
 515         self.ptr_c_ty = "int64_t"
 516         self.ptr_native_ty = "long"
 517         self.u128_native_ty = "UInt128"
 518         self.usize_c_ty = "int64_t"
 519         self.usize_native_ty = "long"
 520         self.native_zero_ptr = "0"
 521         self.result_c_ty = "jclass"
 522         self.ptr_arr = "jobjectArray"
 523         self.is_arr_some_check = ("", " != NULL")
 524         self.get_native_arr_len_call = ("(*env)->GetArrayLength(env, ", ")")
 525
 526     def bindings_footer(self):
 527         return "}\n"
 528
 529     def construct_jenv(self):
 530         res =  "JNIEnv *env;\n"
 531         res += "jint get_jenv_res = (*j_calls->vm)->GetEnv(j_calls->vm, (void**)&env, JNI_VERSION_1_6);\n"
 532         res += "if (get_jenv_res == JNI_EDETACHED) {\n"
 533         if self.target == Target.ANDROID:
 534             res += "\tDO_ASSERT((*j_calls->vm)->AttachCurrentThread(j_calls->vm, &env, NULL) == JNI_OK);\n"
 535         else:
 536             res += "\tDO_ASSERT((*j_calls->vm)->AttachCurrentThread(j_calls->vm, (void**)&env, NULL) == JNI_OK);\n"
 537         res += "} else {\n"
 538         res += "\tDO_ASSERT(get_jenv_res == JNI_OK);\n"
 539         res += "}\n"
 540         return res
 541     def deconstruct_jenv(self):
 542         res = "if (get_jenv_res == JNI_EDETACHED) {\n"
 543         res += "\tDO_ASSERT((*j_calls->vm)->DetachCurrentThread(j_calls->vm) == JNI_OK);\n"
 544         res += "}\n"
 545         return res
 546
 547     def release_native_arr_ptr_call(self, ty_info, arr_var, arr_ptr_var):
 548         if ty_info.subty is None or not ty_info.subty.c_ty.endswith("Array"):
 549             return "(*env)->ReleasePrimitiveArrayCritical(env, " + arr_var + ", " + arr_ptr_var + ", 0)"
 550         return None
 551     def create_native_arr_call(self, arr_len, ty_info):
 552         if ty_info.c_ty == "int8_tArray":
 553             return "(*env)->NewByteArray(env, " + arr_len + ")"
 554         elif ty_info.subty.c_ty.endswith("Array"):
 555             clz_var = ty_info.java_fn_ty_arg[1:].replace("[", "arr_of_")
 556             self.c_array_class_caches.add(clz_var)
 557             return "(*env)->NewObjectArray(env, " + arr_len + ", " + clz_var + "_clz, NULL);\n"
 558         elif ty_info.subty.c_ty == "jstring":
 559             return "(*env)->NewObjectArray(env, " + arr_len + ", String_clz, NULL);\n"
 560         else:
 561             return "(*env)->New" + ty_info.java_ty.strip("[]").title() + "Array(env, " + arr_len + ")"
 562     def set_native_arr_contents(self, arr_name, arr_len, ty_info):
 563         if ty_info.c_ty == "int8_tArray":
 564             return ("(*env)->SetByteArrayRegion(env, " + arr_name + ", 0, " + arr_len + ", ", ")")
 565         elif ty_info.c_ty == "int16_tArray":
 566             return ("(*env)->SetShortArrayRegion(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 "String" in ty_info.java_ty:
 571             return None
 572         if ty_info.c_ty == "int8_tArray" or ty_info.c_ty == "int16_tArray":
 573             fn_ty = "Byte" if ty_info.c_ty == "int8_tArray" else "Short"
 574             if copy:
 575                 return "(*env)->Get" + fn_ty + "ArrayRegion(env, " + arr_name + ", 0, " + arr_len + ", " + dest_name + ")"
 576             else:
 577                 return "(*env)->Get" + fn_ty + "ArrayElements (env, " + arr_name + ", NULL)"
 578         elif not ty_info.java_ty[:len(ty_info.java_ty) - 2].endswith("[]"):
 579             return "(*env)->Get" + ty_info.subty.java_ty.title() + "ArrayElements (env, " + arr_name + ", NULL)"
 580         else:
 581             return None
 582     def get_native_arr_elem(self, arr_name, idxc, ty_info):
 583         if self.get_native_arr_contents(arr_name, "", "", ty_info, False) is None:
 584             return "(*env)->GetObjectArrayElement(env, " + arr_name + ", " + idxc + ")"
 585         else:
 586             assert False # Only called if above is None
 587     def get_native_arr_ptr_call(self, ty_info):
 588         if ty_info.subty is not None and ty_info.subty.c_ty.endswith("Array"):
 589             return None
 590         return ("(*env)->GetPrimitiveArrayCritical(env, ", ", NULL)")
 591     def get_native_arr_entry_call(self, ty_info, arr_name, idxc, entry_access):
 592         if ty_info.subty is None or not ty_info.subty.c_ty.endswith("Array"):
 593             return None
 594         return "(*env)->SetObjectArrayElement(env, " + arr_name + ", " + idxc + ", " + entry_access + ")"
 595     def cleanup_native_arr_ref_contents(self, arr_name, dest_name, arr_len, ty_info):
 596         if ty_info.c_ty == "int8_tArray":
 597             return "(*env)->ReleaseByteArrayElements(env, " + arr_name + ", (int8_t*)" + dest_name + ", 0);"
 598         else:
 599             return "(*env)->Release" + ty_info.java_ty.strip("[]").title() + "ArrayElements(env, " + arr_name + ", " + dest_name + ", 0)"
 600
 601     def map_hu_array_elems(self, arr_name, conv_name, arr_ty, elem_ty):
 602         if elem_ty.java_ty == "long" and elem_ty.java_hu_ty != "long":
 603             return arr_name + " != null ? Arrays.stream(" + arr_name + ").mapToLong(" + conv_name + " -> " + elem_ty.from_hu_conv[0] + ").toArray() : null"
 604         elif elem_ty.java_ty == "long":
 605             return arr_name + " != null ? Arrays.stream(" + arr_name + ").map(" + conv_name + " -> " + elem_ty.from_hu_conv[0] + ").toArray() : null"
 606         elif elem_ty.java_hu_ty == "UInt5":
 607             return arr_name + " != null ? InternalUtils.convUInt5Array(" + arr_name + ") : null"
 608         elif elem_ty.java_hu_ty == "WitnessVersion":
 609             return arr_name + " != null ? InternalUtils.convWitnessVersionArray(" + arr_name + ") : null"
 610         else:
 611             return arr_name + " != null ? Arrays.stream(" + arr_name + ").map(" + conv_name + " -> " + elem_ty.from_hu_conv[0] + ").toArray(" + arr_ty.java_ty + "::new) : null"
 612
 613     def str_ref_to_native_call(self, var_name, str_len):
 614         return "str_ref_to_java(env, " + var_name + ", " + str_len + ")"
 615     def str_ref_to_c_call(self, var_name):
 616         return "java_to_owned_str(env, " + var_name + ")"
 617     def str_to_hu_conv(self, var_name):
 618         return None
 619     def str_from_hu_conv(self, var_name):
 620         return None
 621
 622     def c_fn_name_define_pfx(self, fn_name, has_args):
 623         if has_args:
 624             return "JNICALL Java_org_ldk_impl_bindings_" + fn_name.replace("_", "_1") + "(JNIEnv *env, jclass clz, "
 625         return "JNICALL Java_org_ldk_impl_bindings_" + fn_name.replace("_", "_1") + "(JNIEnv *env, jclass clz"
 626
 627     def init_str(self):
 628         res = ""
 629         for ty in sorted(self.c_array_class_caches):
 630             res = res + "static jclass " + ty + "_clz = NULL;\n"
 631         res = res + "static jclass String_clz = NULL;\n"
 632         res = res + "JNIEXPORT void Java_org_ldk_impl_bindings_init_1class_1cache(JNIEnv * env, jclass clz) {\n"
 633         for ty in sorted(self.c_array_class_caches):
 634             res = res + "\t" + ty + "_clz = (*env)->FindClass(env, \"" + ty.replace("arr_of_", "[") + "\");\n"
 635             res = res + "\tCHECK(" + ty + "_clz != NULL);\n"
 636             res = res + "\t" + ty + "_clz = (*env)->NewGlobalRef(env, " + ty + "_clz);\n"
 637         res = res + "\tString_clz = (*env)->FindClass(env, \"java/lang/String\");\n"
 638         res = res + "\tCHECK(String_clz != NULL);\n"
 639         res = res + "\tString_clz = (*env)->NewGlobalRef(env, String_clz);\n"
 640
 641         res = res + "}\n"
 642         return res
 643
 644     def var_decl_statement(self, ty_string, var_name, statement):
 645         return ty_string + " " + var_name + " = " + statement
 646
 647     def get_java_arr_len(self, arr_name):
 648         return arr_name + ".length"
 649     def get_java_arr_elem(self, elem_ty, arr_name, idx):
 650         return arr_name + "[" + idx + "]"
 651     def constr_hu_array(self, ty_info, arr_len):
 652         base_ty = ty_info.subty.java_hu_ty.split("[")[0].split("<")[0]
 653         conv = "new " + base_ty + "[" + arr_len + "]"
 654         if "[" in ty_info.subty.java_hu_ty.split("<")[0]:
 655             # Do a bit of a dance to move any excess [] to the end
 656             conv += "[" + ty_info.subty.java_hu_ty.split("<")[0].split("[")[1]
 657         return conv
 658     def cleanup_converted_native_array(self, ty_info, arr_name):
 659         return None
 660
 661     def primitive_arr_from_hu(self, arr_ty, fixed_len, arr_name):
 662         mapped_ty = arr_ty.subty
 663         if arr_ty.rust_obj == "LDKU128":
 664             return ("" + arr_name + ".getLEBytes()", "")
 665         if fixed_len is not None:
 666             if mapped_ty.c_ty == "int8_t" or mapped_ty.c_ty == "uint8_t":
 667                 return ("InternalUtils.check_arr_len(" + arr_name + ", " + fixed_len + ")", "")
 668             elif mapped_ty.c_ty == "int16_t" or mapped_ty.c_ty == "uint16_t":
 669                 return ("InternalUtils.check_arr_16_len(" + arr_name + ", " + fixed_len + ")", "")
 670             else:
 671                 print(arr_ty.c_ty)
 672                 assert False
 673         return None
 674     def primitive_arr_to_hu(self, arr_ty, fixed_len, arr_name, conv_name):
 675         if arr_ty.rust_obj == "LDKU128":
 676             return "org.ldk.util.UInt128 " + conv_name + " = new org.ldk.util.UInt128(" + arr_name + ");"
 677         return None
 678
 679     def java_arr_ty_str(self, elem_ty_str):
 680         return elem_ty_str + "[]"
 681
 682     def for_n_in_range(self, n, minimum, maximum):
 683         return "for (int " + n + " = " + minimum + "; " + n + " < " + maximum + "; " + n + "++) {"
 684     def for_n_in_arr(self, n, arr_name, arr_elem_ty):
 685         return ("for (" + arr_elem_ty.java_hu_ty + " " + n + ": " + arr_name + ") { ", " }")
 686
 687     def get_ptr(self, var):
 688         return var + ".ptr"
 689     def set_null_skip_free(self, var):
 690         return var + ".ptr" + " = 0;"
 691
 692     def add_ref(self, holder, referent):
 693         return "if (" + holder + " != null) { " + holder + ".ptrs_to.add(" + referent + "); }"
 694
 695     def fully_qualified_hu_ty_path(self, ty):
 696         if ty.java_fn_ty_arg.startswith("L") and ty.java_fn_ty_arg.endswith(";"):
 697             return ty.java_fn_ty_arg.strip("L;").replace("/", ".")
 698         if ty.java_hu_ty == "UnqualifiedError" or ty.java_hu_ty == "UInt128" or ty.java_hu_ty == "UInt5" or ty.java_hu_ty == "WitnessVersion":
 699             return "org.ldk.util." + ty.java_hu_ty
 700         if not ty.is_native_primitive and ty.rust_obj is not None and not "[]" in ty.java_hu_ty:
 701             return "org.ldk.structs." + ty.java_hu_ty
 702         return ty.java_hu_ty
 703
 704     def native_c_unitary_enum_map(self, struct_name, variants, enum_doc_comment):
 705         out_java_enum = "package org.ldk.enums;\n\n"
 706         out_java = ""
 707         out_c = ""
 708         out_c += "static inline LDK" + struct_name + " LDK" + struct_name + "_from_java(" + self.c_fn_args_pfx + ") {\n"
 709         out_c += "\tjint ord = (*env)->CallIntMethod(env, clz, ordinal_meth);\n"
 710         out_c += "\tif (UNLIKELY((*env)->ExceptionCheck(env))) {\n"
 711         out_c += "\t\t(*env)->ExceptionDescribe(env);\n"
 712         out_c += "\t\t(*env)->FatalError(env, \"A call to " + struct_name + ".ordinal() from rust threw an exception.\");\n"
 713         out_c += "\t}\n"
 714         out_c += "\tswitch (ord) {\n"
 715
 716         if enum_doc_comment is not None:
 717             out_java_enum += "/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
 718         out_java_enum += "public enum " + struct_name + " {\n"
 719         ord_v = 0
 720         for var, var_docs in variants:
 721             if var_docs is not None:
 722                 out_java_enum += "\t/**\n\t * " + var_docs.replace("\n", "\n\t * ") + "\n\t */\n"
 723             out_java_enum += "\t" + var + ",\n"
 724             out_c = out_c + "\t\tcase %d: return %s;\n" % (ord_v, var)
 725             ord_v = ord_v + 1
 726         out_java_enum = out_java_enum + "\t; static native void init();\n"
 727         out_java_enum = out_java_enum + "\tstatic { init(); }\n"
 728         out_java_enum = out_java_enum + "}"
 729         out_java = out_java + "\tstatic { " + struct_name + ".values(); /* Force enum statics to run */ }\n"
 730         out_c += "\t}\n"
 731         out_c += "\t(*env)->FatalError(env, \"A call to " + struct_name + ".ordinal() from rust returned an invalid value.\");\n"
 732         out_c += "\tabort(); // Unreachable, but will let the compiler know we don't return here\n"
 733         out_c += "}\n"
 734
 735         out_c = out_c + "static jclass " + struct_name + "_class = NULL;\n"
 736         for var, _ in variants:
 737             out_c = out_c + "static jfieldID " + struct_name + "_" + var + " = NULL;\n"
 738         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"
 739         out_c = out_c + "\t" + struct_name + "_class = (*env)->NewGlobalRef(env, clz);\n"
 740         out_c = out_c + "\tCHECK(" + struct_name + "_class != NULL);\n"
 741         for var, _ in variants:
 742             out_c = out_c + "\t" + struct_name + "_" + var + " = (*env)->GetStaticFieldID(env, " + struct_name + "_class, \"" + var + "\", \"Lorg/ldk/enums/" + struct_name + ";\");\n"
 743             out_c = out_c + "\tCHECK(" + struct_name + "_" + var + " != NULL);\n"
 744         out_c = out_c + "}\n"
 745         out_c = out_c + "static inline jclass LDK" + struct_name + "_to_java(JNIEnv *env, LDK" + struct_name + " val) {\n"
 746         out_c = out_c + "\tswitch (val) {\n"
 747         ord_v = 0
 748         for var, _ in variants:
 749             out_c = out_c + "\t\tcase " + var + ":\n"
 750             out_c = out_c + "\t\t\treturn (*env)->GetStaticObjectField(env, " + struct_name + "_class, " + struct_name + "_" + var + ");\n"
 751             ord_v = ord_v + 1
 752         out_c = out_c + "\t\tdefault: abort();\n"
 753         out_c = out_c + "\t}\n"
 754         out_c = out_c + "}\n\n"
 755
 756         return (out_c, out_java_enum, out_java)
 757
 758     def c_unitary_enum_to_native_call(self, ty_info):
 759         return (ty_info.rust_obj + "_to_java(env, ", ")")
 760     def native_unitary_enum_to_c_call(self, ty_info):
 761         return (ty_info.rust_obj + "_from_java(env, ", ")")
 762
 763     def c_complex_enum_pfx(self, struct_name, variants, init_meth_jty_strs):
 764         out_c = ""
 765         for var in variants:
 766             out_c = out_c + "static jclass " + struct_name + "_" + var + "_class = NULL;\n"
 767             out_c = out_c + "static jmethodID " + struct_name + "_" + var + "_meth = NULL;\n"
 768         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"
 769         for var_name in variants:
 770             out_c += "\t" + struct_name + "_" + var_name + "_class =\n"
 771             out_c += "\t\t(*env)->NewGlobalRef(env, (*env)->FindClass(env, \"org/ldk/impl/bindings$" + struct_name + "$" + var_name + "\"));\n"
 772             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_class != NULL);\n"
 773             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"
 774             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_meth != NULL);\n"
 775         out_c = out_c + "}\n"
 776         return out_c
 777
 778     def c_complex_enum_pass_ty(self, struct_name):
 779         return "jobject"
 780
 781     def c_constr_native_complex_enum(self, struct_name, variant, c_params):
 782         ret = "(*env)->NewObject(env, " + struct_name + "_" + variant + "_class, " + struct_name + "_" + variant + "_meth"
 783         for param in c_params:
 784             ret = ret + ", " + param
 785         return ret + ")"
 786
 787     def native_c_map_trait(self, struct_name, field_vars, flattened_field_vars, field_fns, trait_doc_comment):
 788         out_java_trait = ""
 789         out_java = ""
 790
 791         # First generate most of the Java code, note that we need information about java method argument strings for C
 792         out_java_trait = out_java_trait + self.hu_struct_file_prefix
 793         if trait_doc_comment is not None:
 794             out_java_trait += "/**\n * " + trait_doc_comment.replace("\n", "\n * ") + "\n */\n"
 795         out_java_trait += "@SuppressWarnings(\"unchecked\") // We correctly assign various generic arrays\n"
 796         out_java_trait = out_java_trait + "public class " + struct_name.replace("LDK","") + " extends CommonBase {\n"
 797         out_java_trait = out_java_trait + "\tfinal bindings." + struct_name + " bindings_instance;\n"
 798         out_java_trait = out_java_trait + "\t" + struct_name.replace("LDK", "") + "(Object _dummy, long ptr) { super(ptr); bindings_instance = null; }\n"
 799         out_java_trait = out_java_trait + "\tprivate " + struct_name.replace("LDK", "") + "(bindings." + struct_name + " arg"
 800         for var in flattened_field_vars:
 801             if isinstance(var, ConvInfo):
 802                 out_java_trait = out_java_trait + ", " + var.java_hu_ty + " " + var.arg_name
 803             else:
 804                 out_java_trait = out_java_trait + ", bindings." + var[0] + " " + var[1]
 805         out_java_trait = out_java_trait + ") {\n"
 806         out_java_trait = out_java_trait + "\t\tsuper(bindings." + struct_name + "_new(arg"
 807         for var in flattened_field_vars:
 808             if isinstance(var, ConvInfo):
 809                 if var.from_hu_conv is not None:
 810                     out_java_trait = out_java_trait + ", " + var.from_hu_conv[0]
 811                 else:
 812                     out_java_trait = out_java_trait + ", " + var.arg_name
 813             else:
 814                 out_java_trait = out_java_trait + ", " + var[1]
 815         out_java_trait = out_java_trait + "));\n"
 816         out_java_trait = out_java_trait + "\t\tthis.ptrs_to.add(arg);\n"
 817         for var in flattened_field_vars:
 818             if isinstance(var, ConvInfo):
 819                 if var.from_hu_conv is not None and var.from_hu_conv[1] != "":
 820                     out_java_trait = out_java_trait + "\t\t" + var.from_hu_conv[1].replace("\n", "\n\t\t") + ";\n"
 821             else:
 822                 out_java_trait = out_java_trait + "\t\tthis.ptrs_to.add(" + var[1] + ");\n"
 823         out_java_trait += f"""          this.bindings_instance = arg;
 824         }}
 825         @Override @SuppressWarnings("deprecation")
 826         protected void finalize() throws Throwable {{
 827                 if (ptr != 0) {{ bindings.{struct_name.replace("LDK","")}_free(ptr); }} super.finalize();
 828         }}
 829         /**
 830          * Destroys the object, freeing associated resources. After this call, any access
 831          * to this object may result in a SEGFAULT or worse.
 832          *
 833          * You should generally NEVER call this method. You should let the garbage collector
 834          * do this for you when it finalizes objects. However, it may be useful for types
 835          * which represent locks and should be closed immediately to avoid holding locks
 836          * until the GC runs.
 837          */
 838         public void destroy() {{
 839                 if (ptr != 0) {{ bindings.{struct_name.replace("LDK","")}_free(ptr); }}
 840                 ptr = 0;
 841         }}
 842 """
 843
 844         java_trait_constr = "\tprivate static class " + struct_name + "Holder { " + struct_name.replace("LDK", "") + " held; }\n"
 845         java_trait_constr = java_trait_constr + "\tpublic static " + struct_name.replace("LDK", "") + " new_impl(" + struct_name.replace("LDK", "") + "Interface arg"
 846         for var in flattened_field_vars:
 847             if isinstance(var, ConvInfo):
 848                 java_trait_constr = java_trait_constr + ", " + var.java_hu_ty + " " + var.arg_name
 849             else:
 850                 # Ideally we'd be able to take any instance of the interface, but our C code can only represent
 851                 # Java-implemented version, so we require users pass a Java implementation here :/
 852                 java_trait_constr = java_trait_constr + ", " + var[0].replace("LDK", "") + "." + var[0].replace("LDK", "") + "Interface " + var[1] + "_impl"
 853         java_trait_constr = java_trait_constr + ") {\n\t\tfinal " + struct_name + "Holder impl_holder = new " + struct_name + "Holder();\n"
 854         java_trait_constr = java_trait_constr + "\t\timpl_holder.held = new " + struct_name.replace("LDK", "") + "(new bindings." + struct_name + "() {\n"
 855         out_java_trait = out_java_trait + "\tpublic static interface " + struct_name.replace("LDK", "") + "Interface {\n"
 856         out_java = out_java + "\tpublic interface " + struct_name + " {\n"
 857         java_meths = []
 858         for fn_line in field_fns:
 859             java_meth_descr = "("
 860             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 861                 out_java = out_java + "\t\t " + fn_line.ret_ty_info.java_ty + " " + fn_line.fn_name + "("
 862                 java_trait_constr = java_trait_constr + "\t\t\t@Override public " + fn_line.ret_ty_info.java_ty + " " + fn_line.fn_name + "("
 863                 out_java_trait += "\t\t/**\n\t\t * " + fn_line.docs.replace("\n", "\n\t\t * ") + "\n\t\t */\n"
 864                 out_java_trait = out_java_trait + "\t\t" + fn_line.ret_ty_info.java_hu_ty + " " + fn_line.fn_name + "("
 865
 866                 for idx, arg_conv_info in enumerate(fn_line.args_ty):
 867                     if idx >= 1:
 868                         out_java = out_java + ", "
 869                         java_trait_constr = java_trait_constr + ", "
 870                         out_java_trait = out_java_trait + ", "
 871                     out_java = out_java + arg_conv_info.java_ty + " " + arg_conv_info.arg_name
 872                     out_java_trait = out_java_trait + arg_conv_info.java_hu_ty + " " + arg_conv_info.arg_name
 873                     java_trait_constr = java_trait_constr + arg_conv_info.java_ty + " " + arg_conv_info.arg_name
 874                     java_meth_descr = java_meth_descr + arg_conv_info.java_fn_ty_arg
 875                 java_meth_descr = java_meth_descr + ")" + fn_line.ret_ty_info.java_fn_ty_arg
 876                 java_meths.append((fn_line.fn_name, java_meth_descr))
 877
 878                 out_java = out_java + ");\n"
 879                 out_java_trait = out_java_trait + ");\n"
 880                 java_trait_constr = java_trait_constr + ") {\n"
 881
 882                 for arg_info in fn_line.args_ty:
 883                     if arg_info.to_hu_conv is not None:
 884                         java_trait_constr = java_trait_constr + "\t\t\t\t" + arg_info.to_hu_conv.replace("\n", "\n\t\t\t\t") + "\n"
 885
 886                 if fn_line.ret_ty_info.java_ty != "void":
 887                     java_trait_constr = java_trait_constr + "\t\t\t\t" + fn_line.ret_ty_info.java_hu_ty + " ret = arg." + fn_line.fn_name + "("
 888                 else:
 889                     java_trait_constr = java_trait_constr + "\t\t\t\targ." + fn_line.fn_name + "("
 890
 891                 for idx, arg_info in enumerate(fn_line.args_ty):
 892                     if idx != 0:
 893                         java_trait_constr = java_trait_constr + ", "
 894                     if arg_info.to_hu_conv_name is not None:
 895                         java_trait_constr = java_trait_constr + arg_info.to_hu_conv_name
 896                     else:
 897                         java_trait_constr = java_trait_constr + arg_info.arg_name
 898
 899                 java_trait_constr += ");\n"
 900                 java_trait_constr += "\t\t\t\tReference.reachabilityFence(arg);\n"
 901                 if fn_line.ret_ty_info.java_ty != "void":
 902                     if fn_line.ret_ty_info.from_hu_conv is not None:
 903                         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"
 904                         if fn_line.ret_ty_info.from_hu_conv[1] != "":
 905                             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"
 906                         #if fn_line.ret_ty_info.rust_obj in result_types:
 907                         java_trait_constr = java_trait_constr + "\t\t\t\treturn result;\n"
 908                     else:
 909                         java_trait_constr = java_trait_constr + "\t\t\t\treturn ret;\n"
 910                 java_trait_constr = java_trait_constr + "\t\t\t}\n"
 911         java_trait_constr = java_trait_constr + "\t\t}"
 912         for var in field_vars:
 913             if isinstance(var, ConvInfo):
 914                 java_trait_constr = java_trait_constr + ", " + var.arg_name
 915             else:
 916                 java_trait_constr += ", " + var[1] + ".new_impl(" + var[1] + "_impl"
 917                 suptrait_constr = ""
 918                 for suparg in var[2]:
 919                     if isinstance(suparg, ConvInfo):
 920                         suptrait_constr += ", " + suparg.arg_name
 921                     else:
 922                         suptrait_constr += ", " + suparg[1] + "_impl"
 923                 java_trait_constr += suptrait_constr + ").bindings_instance"
 924                 for suparg in var[2]:
 925                     if isinstance(suparg, ConvInfo):
 926                         java_trait_constr += ", " + suparg.arg_name
 927                     else:
 928                         java_trait_constr += ", " + suparg[1] + ".new_impl("
 929                         # Blindly assume that we can just strip the first arg to build the args for the supertrait
 930                         java_trait_constr += suptrait_constr.split(", ", 1)[1]
 931                         java_trait_constr += ").bindings_instance"
 932         out_java_trait = out_java_trait + "\t}\n"
 933         out_java_trait = out_java_trait + java_trait_constr + ");\n\t\treturn impl_holder.held;\n\t}\n"
 934
 935         out_java = out_java + "\t}\n"
 936
 937         out_java = out_java + "\tpublic static native long " + struct_name + "_new(" + struct_name + " impl"
 938         for var in flattened_field_vars:
 939             if isinstance(var, ConvInfo):
 940                 out_java = out_java + ", " + var.java_ty + " " + var.arg_name
 941             else:
 942                 out_java = out_java + ", " + var[0] + " " + var[1]
 943         out_java = out_java + ");\n"
 944
 945         # Now that we've written out our java code (and created java_meths), generate C
 946         out_c = "typedef struct " + struct_name + "_JCalls {\n"
 947         out_c = out_c + "\tatomic_size_t refcnt;\n"
 948         out_c = out_c + "\tJavaVM *vm;\n"
 949         out_c = out_c + "\tjweak o;\n"
 950         for var in flattened_field_vars:
 951             if isinstance(var, ConvInfo):
 952                 # We're a regular ol' field
 953                 pass
 954             else:
 955                 # We're a supertrait
 956                 out_c = out_c + "\t" + var[0] + "_JCalls* " + var[1] + ";\n"
 957         for fn in field_fns:
 958             if fn.fn_name != "free" and fn.fn_name != "cloned":
 959                 out_c = out_c + "\tjmethodID " + fn.fn_name + "_meth;\n"
 960         out_c = out_c + "} " + struct_name + "_JCalls;\n"
 961
 962         for fn_line in field_fns:
 963             if fn_line.fn_name == "free":
 964                 out_c = out_c + "static void " + struct_name + "_JCalls_free(void* this_arg) {\n"
 965                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
 966                 out_c = out_c + "\tif (atomic_fetch_sub_explicit(&j_calls->refcnt, 1, memory_order_acquire) == 1) {\n"
 967                 out_c += "\t\t" + self.construct_jenv().replace("\n", "\n\t\t").strip() + "\n"
 968                 out_c = out_c + "\t\t(*env)->DeleteWeakGlobalRef(env, j_calls->o);\n"
 969                 out_c += "\t\t" + self.deconstruct_jenv().replace("\n", "\n\t\t").strip() + "\n"
 970                 out_c = out_c + "\t\tFREE(j_calls);\n"
 971                 out_c = out_c + "\t}\n}\n"
 972
 973         for idx, fn_line in enumerate(field_fns):
 974             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 975                 assert fn_line.ret_ty_info.ty_info.get_full_rust_ty()[1] == ""
 976                 out_c = out_c + fn_line.ret_ty_info.ty_info.get_full_rust_ty()[0] + " " + fn_line.fn_name + "_" + struct_name + "_jcall("
 977                 if fn_line.self_is_const:
 978                     out_c = out_c + "const void* this_arg"
 979                 else:
 980                     out_c = out_c + "void* this_arg"
 981
 982                 for idx, arg in enumerate(fn_line.args_ty):
 983                     out_c = out_c + ", " + arg.ty_info.get_full_rust_ty()[0] + " " + arg.arg_name + arg.ty_info.get_full_rust_ty()[1]
 984
 985                 out_c = out_c + ") {\n"
 986                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
 987                 out_c += "\t" + self.construct_jenv().replace("\n", "\n\t").strip() + "\n"
 988
 989                 for arg_info in fn_line.args_ty:
 990                     if arg_info.ret_conv is not None:
 991                         out_c = out_c + "\t" + arg_info.ret_conv[0].replace('\n', '\n\t')
 992                         out_c = out_c + arg_info.arg_name
 993                         out_c = out_c + arg_info.ret_conv[1].replace('\n', '\n\t') + "\n"
 994
 995                 out_c = out_c + "\tjobject obj = (*env)->NewLocalRef(env, j_calls->o);\n\tCHECK(obj != NULL);\n"
 996                 if fn_line.ret_ty_info.c_ty.endswith("Array"):
 997                     out_c = out_c + "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->CallObjectMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 998                 elif fn_line.ret_ty_info.c_ty == "void":
 999                     out_c += "\t(*env)->CallVoidMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
1000                 elif fn_line.ret_ty_info.java_hu_ty == "String" or "org/ldk/enums" in fn_line.ret_ty_info.java_fn_ty_arg:
1001                     # Manually write out String methods as they're just an Object
1002                     out_c += "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->CallObjectMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
1003                 elif not fn_line.ret_ty_info.passed_as_ptr:
1004                     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"
1005                 else:
1006                     out_c = out_c + "\tuint64_t ret = (*env)->CallLongMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
1007
1008                 for idx, arg_info in enumerate(fn_line.args_ty):
1009                     if arg_info.ret_conv is not None:
1010                         out_c = out_c + ", " + arg_info.ret_conv_name
1011                     else:
1012                         out_c = out_c + ", " + arg_info.arg_name
1013                 out_c = out_c + ");\n"
1014
1015                 out_c += "\tif (UNLIKELY((*env)->ExceptionCheck(env))) {\n"
1016                 out_c += "\t\t(*env)->ExceptionDescribe(env);\n"
1017                 out_c += "\t\t(*env)->FatalError(env, \"A call to " + fn_line.fn_name + " in " + struct_name + " from rust threw an exception.\");\n"
1018                 out_c += "\t}\n"
1019
1020                 if fn_line.ret_ty_info.arg_conv is not None:
1021                     out_c += "\t" + fn_line.ret_ty_info.arg_conv.replace("\n", "\n\t") + "\n"
1022                     out_c += "\t" + self.deconstruct_jenv().replace("\n", "\n\t").strip() + "\n"
1023                     out_c += "\treturn " + fn_line.ret_ty_info.arg_conv_name + ";\n"
1024                 else:
1025                     out_c += "\t" + self.deconstruct_jenv().replace("\n", "\n\t").strip() + "\n"
1026                     if not fn_line.ret_ty_info.passed_as_ptr and fn_line.ret_ty_info.c_ty != "void":
1027                         out_c += "\treturn ret;\n"
1028
1029                 out_c = out_c + "}\n"
1030
1031         # If we can, write out a clone function whether we need one or not, as we use them in moving to rust
1032         can_clone_with_ptr = True
1033         for var in field_vars:
1034             if isinstance(var, ConvInfo):
1035                 can_clone_with_ptr = False
1036         if can_clone_with_ptr:
1037             out_c = out_c + "static void " + struct_name + "_JCalls_cloned(" + struct_name + "* new_obj) {\n"
1038             out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) new_obj->this_arg;\n"
1039             out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->refcnt, 1, memory_order_release);\n"
1040             for var in flattened_field_vars:
1041                 if not isinstance(var, ConvInfo):
1042                     out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->" + var[2].replace(".", "->") + "->refcnt, 1, memory_order_release);\n"
1043             out_c = out_c + "}\n"
1044
1045         out_c = out_c + "static inline " + struct_name + " " + struct_name + "_init (" + self.c_fn_args_pfx + ", jobject o"
1046         for var in flattened_field_vars:
1047             if isinstance(var, ConvInfo):
1048                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
1049             else:
1050                 out_c = out_c + ", jobject " + var[1]
1051         out_c = out_c + ") {\n"
1052
1053         out_c = out_c + "\tjclass c = (*env)->GetObjectClass(env, o);\n"
1054         out_c = out_c + "\tCHECK(c != NULL);\n"
1055         out_c = out_c + "\t" + struct_name + "_JCalls *calls = MALLOC(sizeof(" + struct_name + "_JCalls), \"" + struct_name + "_JCalls\");\n"
1056         out_c = out_c + "\tatomic_init(&calls->refcnt, 1);\n"
1057         out_c = out_c + "\tDO_ASSERT((*env)->GetJavaVM(env, &calls->vm) == 0);\n"
1058         out_c = out_c + "\tcalls->o = (*env)->NewWeakGlobalRef(env, o);\n"
1059
1060         for (fn_name, java_meth_descr) in java_meths:
1061             if fn_name != "free" and fn_name != "cloned":
1062                 out_c = out_c + "\tcalls->" + fn_name + "_meth = (*env)->GetMethodID(env, c, \"" + fn_name + "\", \"" + java_meth_descr + "\");\n"
1063                 out_c = out_c + "\tCHECK(calls->" + fn_name + "_meth != NULL);\n"
1064
1065         for var in flattened_field_vars:
1066             if isinstance(var, ConvInfo) and var.arg_conv is not None:
1067                 out_c = out_c + "\n\t" + var.arg_conv.replace("\n", "\n\t") +"\n"
1068         out_c = out_c + "\n\t" + struct_name + " ret = {\n"
1069         out_c = out_c + "\t\t.this_arg = (void*) calls,\n"
1070         for fn_line in field_fns:
1071             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
1072                 out_c = out_c + "\t\t." + fn_line.fn_name + " = " + fn_line.fn_name + "_" + struct_name + "_jcall,\n"
1073             elif fn_line.fn_name == "free":
1074                 out_c = out_c + "\t\t.free = " + struct_name + "_JCalls_free,\n"
1075             else:
1076                 out_c = out_c + "\t\t.cloned = " + struct_name + "_JCalls_cloned,\n"
1077         for var in field_vars:
1078             if isinstance(var, ConvInfo):
1079                 if var.arg_conv_name is not None:
1080                     out_c = out_c + "\t\t." + var.arg_name + " = " + var.arg_conv_name + ",\n"
1081                     out_c = out_c + "\t\t.set_" + var.arg_name + " = NULL,\n"
1082                 else:
1083                     out_c = out_c + "\t\t." + var.var_name + " = " + var.var_name + ",\n"
1084                     out_c = out_c + "\t\t.set_" + var.var_name + " = NULL,\n"
1085             else:
1086                 out_c += "\t\t." + var[1] + " = " + var[0] + "_init(env, clz, " + var[1]
1087                 for suparg in var[2]:
1088                     if isinstance(suparg, ConvInfo):
1089                         out_c = out_c + ", " + suparg.arg_name
1090                     else:
1091                         out_c = out_c + ", " + suparg[1]
1092                 out_c += "),\n"
1093         out_c = out_c + "\t};\n"
1094         for var in flattened_field_vars:
1095             if not isinstance(var, ConvInfo):
1096                 out_c = out_c + "\tcalls->" + var[1] + " = ret." + var[2] + ".this_arg;\n"
1097         out_c = out_c + "\treturn ret;\n"
1098         out_c = out_c + "}\n"
1099
1100         out_c = out_c + self.c_fn_ty_pfx + "int64_t " + self.c_fn_name_define_pfx(struct_name + "_new", True) + "jobject o"
1101         for var in flattened_field_vars:
1102             if isinstance(var, ConvInfo):
1103                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
1104             else:
1105                 out_c = out_c + ", jobject " + var[1]
1106         out_c = out_c + ") {\n"
1107         out_c = out_c + "\t" + struct_name + " *res_ptr = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n"
1108         out_c = out_c + "\t*res_ptr = " + struct_name + "_init(env, clz, o"
1109         for var in flattened_field_vars:
1110             if isinstance(var, ConvInfo):
1111                 out_c = out_c + ", " + var.arg_name
1112             else:
1113                 out_c = out_c + ", " + var[1]
1114         out_c = out_c + ");\n"
1115         out_c = out_c + "\treturn tag_ptr(res_ptr, true);\n"
1116         out_c = out_c + "}\n"
1117
1118         for var in flattened_field_vars:
1119             if not isinstance(var, ConvInfo):
1120                 out_java_trait += "\n\t/**\n"
1121                 out_java_trait += "\t * Gets the underlying " + var[1] + ".\n"
1122                 out_java_trait += "\t */\n"
1123                 underscore_name = ''.join('_' + c.lower() if c.isupper() else c for c in var[1]).strip('_')
1124                 out_java_trait += "\tpublic " + var[1] + " get_" + underscore_name + "() {\n"
1125                 out_java_trait += "\t\t" + var[1] + " res = new " + var[1] + "(null, bindings." + struct_name + "_get_" + var[1] + "(this.ptr));\n"
1126                 out_java_trait += "\t\tres.ptrs_to.add(this);\n"
1127                 out_java_trait += "\t\treturn res;\n"
1128                 out_java_trait += "\t}\n"
1129                 out_java_trait += "\n"
1130
1131                 out_java += "\tpublic static native long " + struct_name + "_get_" + var[1] + "(long arg);\n"
1132
1133                 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"
1134                 out_c += "\t" + struct_name + " *inp = (" + struct_name + " *)untag_ptr(arg);\n"
1135                 out_c += "\treturn tag_ptr(&inp->" + var[2] + ", false);\n"
1136                 out_c += "}\n"
1137
1138         return (out_java, out_java_trait, out_c)
1139
1140     def trait_struct_inc_refcnt(self, ty_info):
1141         base_conv = "\nif (" + ty_info.var_name + "_conv.free == " + ty_info.rust_obj + "_JCalls_free) {\n"
1142         base_conv = base_conv + "\t// If this_arg is a JCalls struct, then we need to increment the refcnt in it.\n"
1143         base_conv = base_conv + "\t" + ty_info.rust_obj + "_JCalls_cloned(&" + ty_info.var_name + "_conv);\n}"
1144         return base_conv
1145
1146     def map_complex_enum(self, struct_name, variant_list, camel_to_snake, enum_doc_comment):
1147         java_hu_type = struct_name.replace("LDK", "").replace("COption", "Option")
1148         out_java_enum = ""
1149         out_java = ""
1150         out_c = ""
1151
1152         out_java_enum += (self.hu_struct_file_prefix)
1153         out_java_enum += "\n/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
1154         out_java_enum += "@SuppressWarnings(\"unchecked\") // We correctly assign various generic arrays\n"
1155         out_java_enum += ("public class " + java_hu_type + " extends CommonBase {\n")
1156         out_java_enum += ("\tprivate " + java_hu_type + "(Object _dummy, long ptr) { super(ptr); }\n")
1157         out_java_enum += ("\t@Override @SuppressWarnings(\"deprecation\")\n")
1158         out_java_enum += ("\tprotected void finalize() throws Throwable {\n")
1159         out_java_enum += ("\t\tsuper.finalize();\n")
1160         out_java_enum += ("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK", "") + "_free(ptr); }\n")
1161         out_java_enum += ("\t}\n")
1162         out_java_enum += ("\tstatic " + java_hu_type + " constr_from_ptr(long ptr) {\n")
1163         out_java_enum += ("\t\tbindings." + struct_name + " raw_val = bindings." + struct_name + "_ref_from_ptr(ptr);\n")
1164         java_hu_subclasses = ""
1165
1166         init_meth_jty_strs = {}
1167
1168         out_java +=  ("\tpublic static class " + struct_name + " {\n")
1169         out_java +=  ("\t\tprivate " + struct_name + "() {}\n")
1170         for var in variant_list:
1171             out_java +=  ("\t\tpublic final static class " + var.var_name + " extends " + struct_name + " {\n")
1172             if var.var_docs is not None:
1173                 java_hu_subclasses += "\t/**\n\t * " + var.var_docs.replace("\n", "\n\t * ") + "\n\t */\n"
1174             java_hu_subclasses += "\tpublic final static class " + var.var_name + " extends " + java_hu_type + " {\n"
1175             out_java_enum += ("\t\tif (raw_val.getClass() == bindings." + struct_name + "." + var.var_name + ".class) {\n")
1176             out_java_enum += ("\t\t\treturn new " + var.var_name + "(ptr, (bindings." + struct_name + "." + var.var_name + ")raw_val);\n")
1177             init_meth_jty_str = ""
1178             init_meth_params = ""
1179             init_meth_body = ""
1180             hu_conv_body = ""
1181             for idx, (field_ty, field_docs) in enumerate(var.fields):
1182                 if idx > 0:
1183                     init_meth_params = init_meth_params + ", "
1184
1185                 java_ty = field_ty.java_ty
1186                 if field_ty.java_fn_ty_arg.startswith("L") and field_ty.java_fn_ty_arg.endswith(";"):
1187                     # If this is a simple enum, we have to reference it in the low-level bindings differently:
1188                     java_ty = field_ty.java_fn_ty_arg.strip("L;").replace("/", ".")
1189                 out_java += "\t\t\tpublic " + java_ty + " " + field_ty.arg_name + ";\n"
1190                 if field_docs is not None:
1191                     java_hu_subclasses += "\t\t/**\n\t\t * " + field_docs.replace("\n", "\n\t\t * ") + "\n\t\t*/\n"
1192                 java_hu_subclasses += "\t\t"
1193                 if field_ty.nullable:
1194                     java_hu_subclasses += "@Nullable "
1195                 java_hu_subclasses += "public final " + self.fully_qualified_hu_ty_path(field_ty) + " " + field_ty.arg_name + ";\n"
1196                 init_meth_params = init_meth_params + java_ty + " " + field_ty.arg_name
1197
1198                 init_meth_body = init_meth_body + "this." + field_ty.arg_name + " = " + field_ty.arg_name + "; "
1199                 if field_ty.to_hu_conv is not None:
1200                     hu_conv_body = hu_conv_body + "\t\t\t" + field_ty.java_ty + " " + field_ty.arg_name + " = obj." + field_ty.arg_name + ";\n"
1201                     hu_conv_body = hu_conv_body + "\t\t\t" + field_ty.to_hu_conv.replace("\n", "\n\t\t\t") + "\n"
1202                     hu_conv_body = hu_conv_body + "\t\t\tthis." + field_ty.arg_name + " = " + field_ty.to_hu_conv_name + ";\n"
1203                 else:
1204                     hu_conv_body = hu_conv_body + "\t\t\tthis." + field_ty.arg_name + " = obj." + field_ty.arg_name + ";\n"
1205                 init_meth_jty_str = init_meth_jty_str + field_ty.java_fn_ty_arg
1206             out_java +=  ("\t\t\t" + var.var_name + "(" + init_meth_params + ") { ")
1207             out_java +=  (init_meth_body)
1208             out_java +=  ("}\n")
1209             out_java += ("\t\t}\n")
1210             out_java_enum += ("\t\t}\n")
1211             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"
1212             java_hu_subclasses = java_hu_subclasses + hu_conv_body
1213             java_hu_subclasses = java_hu_subclasses + "\t\t}\n\t}\n"
1214             init_meth_jty_strs[var.var_name] = init_meth_jty_str
1215         out_java += ("\t\tstatic native void init();\n")
1216         out_java += ("\t}\n")
1217         out_java_enum += ("\t\tassert false; return null; // Unreachable without extending the (internal) bindings interface\n\t}\n\n")
1218         out_java_enum += (java_hu_subclasses)
1219         out_java += ("\tstatic { " + struct_name + ".init(); }\n")
1220         out_java += ("\tpublic static native " + struct_name + " " + struct_name + "_ref_from_ptr(long ptr);\n");
1221
1222         out_c += (self.c_complex_enum_pfx(struct_name, [x.var_name for x in variant_list], init_meth_jty_strs))
1223
1224         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")
1225         out_c += ("\t" + struct_name + " *obj = (" + struct_name + "*)untag_ptr(ptr);\n")
1226         out_c += ("\tswitch(obj->tag) {\n")
1227         for var in variant_list:
1228             out_c += ("\t\tcase " + struct_name + "_" + var.var_name + ": {\n")
1229             c_params = []
1230             for idx, (field_map, field_docs) in enumerate(var.fields):
1231                 if field_map.ret_conv is not None:
1232                     out_c += ("\t\t\t" + field_map.ret_conv[0].replace("\n", "\n\t\t\t"))
1233                     if var.tuple_variant:
1234                         out_c += "obj->" + camel_to_snake(var.var_name)
1235                     else:
1236                         out_c += "obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name
1237                     out_c += (field_map.ret_conv[1].replace("\n", "\n\t\t\t") + "\n")
1238                     c_params.append(field_map.ret_conv_name)
1239                 else:
1240                     if var.tuple_variant:
1241                         c_params.append("obj->" + camel_to_snake(var.var_name))
1242                     else:
1243                         c_params.append("obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name)
1244             out_c += ("\t\t\treturn " + self.c_constr_native_complex_enum(struct_name, var.var_name, c_params) + ";\n")
1245             out_c += ("\t\t}\n")
1246         out_c += ("\t\tdefault: abort();\n")
1247         out_c += ("\t}\n}\n")
1248         return (out_java, out_java_enum, out_c)
1249
1250     def map_opaque_struct(self, struct_name, struct_doc_comment):
1251         out_opaque_struct_human = ""
1252         out_opaque_struct_human += self.hu_struct_file_prefix
1253         out_opaque_struct_human += "\n/**\n * " + struct_doc_comment.replace("\n", "\n * ") + "\n */\n"
1254         out_opaque_struct_human += "@SuppressWarnings(\"unchecked\") // We correctly assign various generic arrays\n"
1255         hu_name = struct_name.replace("LDKC2Tuple", "TwoTuple").replace("LDKC3Tuple", "ThreeTuple").replace("LDK", "")
1256         out_opaque_struct_human += ("public class " + hu_name + " extends CommonBase")
1257         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1258             out_opaque_struct_human += (" implements AutoCloseable")
1259         out_opaque_struct_human += (" {\n")
1260         out_opaque_struct_human += ("\t" + hu_name + "(Object _dummy, long ptr) { super(ptr); }\n")
1261         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1262             out_opaque_struct_human += ("\t@Override public void close() {\n")
1263         else:
1264             out_opaque_struct_human += ("\t@Override @SuppressWarnings(\"deprecation\")\n")
1265             out_opaque_struct_human += ("\tprotected void finalize() throws Throwable {\n")
1266             out_opaque_struct_human += ("\t\tsuper.finalize();\n")
1267         out_opaque_struct_human += ("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); }\n")
1268         out_opaque_struct_human += ("\t}\n\n")
1269         return out_opaque_struct_human
1270
1271     def map_tuple(self, struct_name):
1272         return self.map_opaque_struct(struct_name, "A Tuple")
1273
1274     def map_result(self, struct_name, res_map, err_map):
1275         human_ty = struct_name.replace("LDKCResult", "Result")
1276         java_hu_struct = ""
1277         java_hu_struct += self.hu_struct_file_prefix
1278         java_hu_struct += "public class " + human_ty + " extends CommonBase {\n"
1279         java_hu_struct += "\tprivate " + human_ty + "(Object _dummy, long ptr) { super(ptr); }\n"
1280         java_hu_struct += "\tprotected void finalize() throws Throwable {\n"
1281         java_hu_struct += "\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); } super.finalize();\n"
1282         java_hu_struct += "\t}\n\n"
1283         java_hu_struct += "\tstatic " + human_ty + " constr_from_ptr(long ptr) {\n"
1284         java_hu_struct += "\t\tif (bindings." + struct_name.replace("LDK", "") + "_is_ok(ptr)) {\n"
1285         java_hu_struct += "\t\t\treturn new " + human_ty + "_OK(null, ptr);\n"
1286         java_hu_struct += "\t\t} else {\n"
1287         java_hu_struct += "\t\t\treturn new " + human_ty + "_Err(null, ptr);\n"
1288         java_hu_struct += "\t\t}\n"
1289         java_hu_struct += "\t}\n"
1290
1291         java_hu_struct += "\tpublic static final class " + human_ty + "_OK extends " + human_ty + " {\n"
1292
1293         if res_map.java_hu_ty != "void":
1294             java_hu_struct += "\t\tpublic final " + res_map.java_hu_ty + " res;\n"
1295         java_hu_struct += "\t\tprivate " + human_ty + "_OK(Object _dummy, long ptr) {\n"
1296         java_hu_struct += "\t\t\tsuper(_dummy, ptr);\n"
1297         if res_map.java_hu_ty == "void":
1298             pass
1299         elif res_map.to_hu_conv is not None:
1300             java_hu_struct += "\t\t\t" + res_map.java_ty + " res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1301             java_hu_struct += "\t\t\t" + res_map.to_hu_conv.replace("\n", "\n\t\t\t")
1302             java_hu_struct += "\n\t\t\tthis.res = " + res_map.to_hu_conv_name + ";\n"
1303         else:
1304             java_hu_struct += "\t\t\tthis.res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1305         java_hu_struct += "\t\t}\n"
1306         java_hu_struct += "\t}\n\n"
1307
1308         java_hu_struct += "\tpublic static final class " + human_ty + "_Err extends " + human_ty + " {\n"
1309         if err_map.java_hu_ty != "void":
1310             java_hu_struct += "\t\tpublic final " + err_map.java_hu_ty + " err;\n"
1311         java_hu_struct += "\t\tprivate " + human_ty + "_Err(Object _dummy, long ptr) {\n"
1312         java_hu_struct += "\t\t\tsuper(_dummy, ptr);\n"
1313         if err_map.java_hu_ty == "void":
1314             pass
1315         elif err_map.to_hu_conv is not None:
1316             java_hu_struct += "\t\t\t" + err_map.java_ty + " err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1317             java_hu_struct += "\t\t\t" + err_map.to_hu_conv.replace("\n", "\n\t\t\t")
1318             java_hu_struct += "\n\t\t\tthis.err = " + err_map.to_hu_conv_name + ";\n"
1319         else:
1320             java_hu_struct += "\t\t\tthis.err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1321         java_hu_struct += "\t\t}\n"
1322
1323         java_hu_struct += "\t}\n\n"
1324         return java_hu_struct
1325
1326     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):
1327         out_java = ""
1328         out_c = ""
1329         out_java_struct = None
1330
1331         out_java += ("\tpublic static native ")
1332         out_c += (self.c_fn_ty_pfx)
1333         out_c += (return_type_info.c_ty)
1334         out_java += (return_type_info.java_ty)
1335         if return_type_info.ret_conv is not None:
1336             ret_conv_pfx, ret_conv_sfx = return_type_info.ret_conv
1337         out_java += (" " + method_name + "(")
1338         have_args = len(argument_types) > 1 or (len(argument_types) > 0 and argument_types[0].c_ty != "void")
1339         out_c += (" " + self.c_fn_name_define_pfx(method_name, have_args))
1340
1341         for idx, arg_conv_info in enumerate(argument_types):
1342             if idx != 0:
1343                 out_java += (", ")
1344                 out_c += (", ")
1345             if arg_conv_info.c_ty != "void":
1346                 out_c += (arg_conv_info.c_ty + " " + arg_conv_info.arg_name)
1347                 out_java += (arg_conv_info.java_ty + " " + arg_conv_info.arg_name)
1348
1349         out_java_struct = ""
1350         extra_java_struct_out = ""
1351         if not args_known:
1352             out_java_struct += ("\t// Skipped " + method_name + "\n")
1353         else:
1354             if doc_comment is not None:
1355                 out_java_struct += "\t/**\n\t * " + doc_comment.replace("\n", "\n\t * ") + "\n\t */\n"
1356             if return_type_info.nullable:
1357                 out_java_struct += "\t@Nullable\n"
1358             if not takes_self:
1359                 if meth_n == "new":
1360                     out_java_struct += "\tpublic static " + return_type_info.java_hu_ty + " of("
1361                 elif meth_n == "default":
1362                     out_java_struct += "\tpublic static " + return_type_info.java_hu_ty + " with_default("
1363                 else:
1364                     out_java_struct += "\tpublic static " + return_type_info.java_hu_ty + " " + meth_n + "("
1365             elif meth_n == "clone_ptr" or (struct_meth.startswith("LDKCResult") and (meth_n == "get_ok" or meth_n == "get_err")):
1366                 out_java_struct += ("\t" + return_type_info.java_hu_ty + " " + meth_n + "(")
1367             else:
1368                 if meth_n == "hash" and return_type_info.java_hu_ty == "long":
1369                     extra_java_struct_out = "\t@Override public int hashCode() {\n"
1370                     extra_java_struct_out += "\t\treturn (int)this.hash();\n"
1371                     extra_java_struct_out += "\t}\n"
1372                 elif meth_n == "eq" and return_type_info.java_hu_ty == "boolean":
1373                     extra_java_struct_out = "\t@Override public boolean equals(Object o) {\n"
1374                     extra_java_struct_out += "\t\tif (!(o instanceof " + struct_meth + ")) return false;\n"
1375                     extra_java_struct_out += "\t\treturn this.eq((" + struct_meth + ")o);\n"
1376                     extra_java_struct_out += "\t}\n"
1377                 if meth_n == "wait":
1378                     meth_n = "wait_indefinite"
1379                 out_java_struct += ("\tpublic " + return_type_info.java_hu_ty + " " + meth_n + "(")
1380             for idx, arg in enumerate(argument_types):
1381                 if idx != 0:
1382                     if not takes_self or idx > 1:
1383                         out_java_struct += ", "
1384                 elif takes_self:
1385                     continue
1386                 if arg.java_ty != "void":
1387                     if arg.arg_name in default_constructor_args:
1388                         assert not arg.nullable
1389                         for explode_idx, explode_arg in enumerate(default_constructor_args[arg.arg_name]):
1390                             if explode_idx != 0:
1391                                 out_java_struct += (", ")
1392                             out_java_struct += (
1393                                 explode_arg.java_hu_ty + " " + arg.arg_name + "_" + explode_arg.arg_name)
1394                     else:
1395                         if arg.nullable:
1396                             out_java_struct += "@Nullable "
1397                         ty_string = self.fully_qualified_hu_ty_path(arg)
1398                         out_java_struct += ty_string + " " + arg.arg_name
1399         out_java += (");\n")
1400         out_c += (") {\n")
1401         if out_java_struct is not None:
1402             out_java_struct += (") {\n")
1403         for info in argument_types:
1404             if info.arg_conv is not None:
1405                 out_c += ("\t" + info.arg_conv.replace('\n', "\n\t") + "\n")
1406         if return_type_info.ret_conv is not None:
1407             out_c += ("\t" + ret_conv_pfx.replace('\n', '\n\t'))
1408         elif return_type_info.c_ty != "void":
1409             out_c += ("\t" + return_type_info.c_ty + " ret_val = ")
1410         else:
1411             out_c += ("\t")
1412         if c_call_string is None:
1413             out_c += (method_name + "(")
1414         else:
1415             out_c += (c_call_string)
1416         for idx, info in enumerate(argument_types):
1417             if info.arg_conv_name is not None:
1418                 if idx != 0:
1419                     out_c += (", ")
1420                 elif c_call_string is not None:
1421                     continue
1422                 out_c += (info.arg_conv_name)
1423         out_c += (")")
1424         if return_type_info.ret_conv is not None:
1425             out_c += (ret_conv_sfx.replace('\n', '\n\t'))
1426         else:
1427             out_c += (";")
1428         for info in argument_types:
1429             if info.arg_conv_cleanup is not None:
1430                 out_c += ("\n\t" + info.arg_conv_cleanup.replace("\n", "\n\t"))
1431         if return_type_info.ret_conv is not None:
1432             out_c += ("\n\treturn " + return_type_info.ret_conv_name + ";")
1433         elif return_type_info.c_ty != "void":
1434             out_c += ("\n\treturn ret_val;")
1435         out_c += ("\n}\n\n")
1436
1437         if args_known:
1438             out_java_struct += ("\t\t")
1439             if return_type_info.java_ty != "void":
1440                 out_java_struct += (return_type_info.java_ty + " ret = ")
1441             out_java_struct += ("bindings." + method_name + "(")
1442             for idx, info in enumerate(argument_types):
1443                 if idx != 0:
1444                     out_java_struct += (", ")
1445                 if idx == 0 and takes_self:
1446                     out_java_struct += ("this.ptr")
1447                 elif info.arg_name in default_constructor_args:
1448                     out_java_struct += ("bindings." + info.java_hu_ty + "_new(")
1449                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1450                         if explode_idx != 0:
1451                             out_java_struct += (", ")
1452                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1453                         if explode_arg.from_hu_conv is not None:
1454                             out_java_struct += (
1455                                 explode_arg.from_hu_conv[0].replace(explode_arg.arg_name, expl_arg_name))
1456                         else:
1457                             out_java_struct += (expl_arg_name)
1458                     out_java_struct += (")")
1459                 elif info.from_hu_conv is not None:
1460                     out_java_struct += (info.from_hu_conv[0])
1461                 else:
1462                     out_java_struct += (info.arg_name)
1463             out_java_struct += (");\n")
1464
1465             # This is completely nuts. The OpenJDK JRE JIT will optimize out a object which is on
1466             # the stack, calling its finalizer immediately even if member methods are *actively
1467             # executing* on the same object, as long as said object is on the stack. There is no
1468             # concrete specification for when the optimizer is allowed to do this, and when it is
1469             # not, so there is absolutely no way to be certain that this fix suffices.
1470             #
1471             # Instead, the "Java Language Specification" says only that an object is reachable
1472             # (i.e. will not yet be finalized) if it "can be accessed in any potential continuing
1473             # computation from any live thread". To any sensible reader this would mean actively
1474             # executing a member function on an object would make it not eligible for finalization.
1475             # But, no, dear reader, this statement does not say that. Well, okay, it says that,
1476             # very explicitly in fact, but those are just, like, words, man.
1477             #
1478             # In the seemingly non-normative text further down, a few examples of things the
1479             # optimizer can do are given, including "if the values in an object's fields are
1480             # stored in registers[, t]he may then access the registers instead of the object, and
1481             # never access the object again[, implying] that the object is garbage". This appears
1482             # to fully contradict both the above statement, the API documentation in java.lang.ref
1483             # regarding when a reference is "strongly reachable", and basic common sense. There is
1484             # no concrete set of limitations stated, however, seemingly implying the JIT could
1485             # decide your code would run faster by simply garbage collecting everything
1486             # immediately, ensuring your code finishes soon, just by SEGFAULT. Thus, we're really
1487             # entirely flying blind here. We add some fences and hope that its sufficient, but
1488             # with no specification to rely on, we cannot be certain of anything.
1489             #
1490             # TL;DR: The Java Language "Specification" provides no real guarantees on when an
1491             # object will be considered available for garbage collection once the JIT kicks in, so
1492             # we put in some fences and hope to god the JIT doesn't get smarter/more broken.
1493             for idx, info in enumerate(argument_types):
1494                 if idx == 0 and takes_self:
1495                     out_java_struct += ("\t\tReference.reachabilityFence(this);\n")
1496                 elif info.arg_name in default_constructor_args:
1497                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1498                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1499                         out_java_struct += ("\t\tReference.reachabilityFence(" + expl_arg_name + ");\n")
1500                 elif info.c_ty != "void":
1501                     out_java_struct += ("\t\tReference.reachabilityFence(" + info.arg_name + ");\n")
1502
1503             if return_type_info.java_ty == "long" and return_type_info.java_hu_ty != "long":
1504                 out_java_struct += "\t\tif (ret >= 0 && ret <= 4096) { return null; }\n"
1505
1506             if return_type_info.to_hu_conv is not None:
1507                 if not takes_self:
1508                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t").replace("this",
1509                                                                                                                return_type_info.to_hu_conv_name) + "\n")
1510                 else:
1511                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t") + "\n")
1512
1513             for idx, info in enumerate(argument_types):
1514                 if idx == 0 and takes_self:
1515                     pass
1516                 elif info.arg_name in default_constructor_args:
1517                     for explode_arg in default_constructor_args[info.arg_name]:
1518                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1519                         if explode_arg.from_hu_conv is not None and return_type_info.to_hu_conv_name:
1520                             out_java_struct += ("\t\t" + explode_arg.from_hu_conv[1].replace(explode_arg.arg_name,
1521                                                                                                expl_arg_name).replace(
1522                                 "this", return_type_info.to_hu_conv_name) + ";\n")
1523                 elif info.from_hu_conv is not None and info.from_hu_conv[1] != "":
1524                     if not takes_self and return_type_info.to_hu_conv_name is not None:
1525                         out_java_struct += (
1526                             "\t\t" + info.from_hu_conv[1].replace("this", return_type_info.to_hu_conv_name).replace("\n", "\n\t\t") + ";\n")
1527                     else:
1528                         out_java_struct += ("\t\t" + info.from_hu_conv[1].replace("\n", "\n\t\t") + ";\n")
1529
1530             if takes_self and not takes_self_as_ref:
1531                 out_java_struct += "\t\t" + argument_types[0].from_hu_conv[1].replace("\n", "\n\t\t").replace("this_arg", "this") + ";\n"
1532             if return_type_info.to_hu_conv_name is not None:
1533                 out_java_struct += ("\t\treturn " + return_type_info.to_hu_conv_name + ";\n")
1534             elif return_type_info.java_ty != "void" and return_type_info.rust_obj != "LDK" + struct_meth:
1535                 out_java_struct += ("\t\treturn ret;\n")
1536             out_java_struct += ("\t}\n\n")
1537
1538         return (out_java, out_c, out_java_struct + extra_java_struct_out)
1539
1540     def cleanup(self):
1541         pass