_ Git - ldk-java/blob - csharp_strings.py

   1 from bindingstypes import *
   2 from enum import Enum
   3 import sys
   4
   5 class Target(Enum):
   6     CSHARP = 1,
   7
   8 def first_to_lower(string: str) -> str:
   9     first = string[0]
  10     return first.lower() + string[1:]
  11
  12 def safe_arg_name(arg_name):
  13     return "_" + arg_name if arg_name == "lock" or arg_name == "event" or arg_name == "params" else arg_name
  14
  15 def arg_name_repl(s, arg_name):
  16     return s.replace(arg_name, "_" + arg_name) if arg_name == "lock" or arg_name == "event" or arg_name == "params" else s
  17
  18 class Consts:
  19     def __init__(self, DEBUG: bool, target: Target, outdir: str, **kwargs):
  20         self.outdir = outdir
  21         self.target = target
  22         self.c_array_class_caches = set()
  23         self.function_ptr_counter = 0
  24         self.function_ptrs = {}
  25         self.c_type_map = dict(
  26             bool = ['bool', 'long', 'bool[]'],
  27             uint8_t = ['byte', 'long', 'byte[]'],
  28             uint16_t = ['short', 'long', 'short[]'],
  29             uint32_t = ['int', 'long', 'int[]'],
  30             uint64_t = ['long', 'long', 'long[]'],
  31             int64_t = ['long', 'long', 'long[]'],
  32             double = ['double', 'long', 'double[]'],
  33         )
  34         self.java_type_map = dict(
  35             String = "long"
  36         )
  37         self.java_hu_type_map = dict(
  38             String = "string"
  39         )
  40
  41         self.to_hu_conv_templates = dict(
  42             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}); }',
  43             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}); }'
  44         )
  45
  46         self.bindings_header = """
  47 using org.ldk.enums;
  48 using org.ldk.impl;
  49 using System;
  50 using System.Collections.Generic;
  51 using System.Runtime.InteropServices;
  52
  53 namespace org { namespace ldk { namespace impl {
  54
  55 internal class bindings {
  56         static List<WeakReference> js_objs = new List<WeakReference>();
  57
  58 """
  59         self.bindings_header += self.native_meth_decl("get_lib_version_string", "string") + "();\n"
  60         self.bindings_header += self.native_meth_decl("get_ldk_c_bindings_version", "string") + "();\n"
  61         self.bindings_header += self.native_meth_decl("get_ldk_version", "string") + "();\n\n"
  62         self.bindings_header += self.native_meth_decl("allocate_buffer", "long") + "(long buflen);\n\n"
  63         self.bindings_header += self.native_meth_decl("free_buffer", "void") + "(long buf);\n\n"
  64
  65         self.bindings_version_file = """
  66
  67 public class version {
  68         public static string get_ldk_java_bindings_version() {
  69                 return "<git_version_ldk_garbagecollected>";
  70         }
  71 }"""
  72
  73         self.util_fn_pfx = """using org.ldk.impl;
  74 using org.ldk.enums;
  75 using org.ldk.util;
  76 using org.ldk.structs;
  77 using System;
  78
  79 namespace org { namespace ldk { namespace util {
  80 public class UtilMethods {
  81 """
  82         self.util_fn_sfx = "} } } }"
  83         self.common_base = """using System.Collections.Generic;
  84 using System.Diagnostics;
  85
  86 public class CommonBase {
  87         protected internal long ptr;
  88         protected internal LinkedList<object> ptrs_to = new LinkedList<object>();
  89         protected CommonBase(long ptr) { Trace.Assert(ptr < 0 || ptr > 4096); this.ptr = ptr; }
  90 }
  91 """
  92
  93         self.txin_defn = """public class TxIn : CommonBase {
  94         /** The witness in this input, in serialized form */
  95         public readonly byte[] witness;
  96         /** The script_sig in this input */
  97         public readonly byte[] script_sig;
  98         /** The transaction output's sequence number */
  99         public readonly int sequence;
 100         /** The txid this input is spending */
 101         public readonly byte[] previous_txid;
 102         /** The output index within the spent transaction of the output this input is spending */
 103         public readonly int previous_vout;
 104
 105         internal TxIn(object _dummy, long ptr) : base(ptr) {
 106                 this.witness = InternalUtils.decodeUint8Array(bindings.TxIn_get_witness(ptr));
 107                 this.script_sig = InternalUtils.decodeUint8Array(bindings.TxIn_get_script_sig(ptr));
 108                 this.sequence = bindings.TxIn_get_sequence(ptr);
 109                 this.previous_txid = InternalUtils.decodeUint8Array(bindings.TxIn_get_previous_txid(ptr));
 110                 this.previous_vout = bindings.TxIn_get_previous_vout(ptr);
 111         }
 112         public TxIn(byte[] witness, byte[] script_sig, int sequence, byte[] previous_txid, int previous_vout)
 113         : this(null, bindings.TxIn_new(InternalUtils.encodeUint8Array(witness), InternalUtils.encodeUint8Array(script_sig), sequence, InternalUtils.encodeUint8Array(previous_txid), previous_vout)) {}
 114
 115         ~TxIn() {
 116                 if (ptr != 0) { bindings.TxIn_free(ptr); }
 117         }
 118 }"""
 119
 120         self.txout_defn = """public class TxOut : CommonBase {
 121         /** The script_pubkey in this output */
 122         public readonly byte[] script_pubkey;
 123         /** The value, in satoshis, of this output */
 124         public readonly long value;
 125
 126     internal TxOut(object _dummy, long ptr) : base(ptr) {
 127                 this.script_pubkey = InternalUtils.decodeUint8Array(bindings.TxOut_get_script_pubkey(ptr));
 128                 this.value = bindings.TxOut_get_value(ptr);
 129         }
 130     public TxOut(long value, byte[] script_pubkey) : this(null, bindings.TxOut_new(InternalUtils.encodeUint8Array(script_pubkey), value)) {}
 131
 132         ~TxOut() {
 133                 if (ptr != 0) { bindings.TxOut_free(ptr); }
 134         }
 135 }"""
 136
 137         self.scalar_defn = """public class BigEndianScalar : CommonBase {
 138         /** The bytes of the scalar value, in big endian */
 139         public readonly byte[] scalar_bytes;
 140
 141     internal BigEndianScalar(object _dummy, long ptr) : base(ptr) {
 142                 this.scalar_bytes = InternalUtils.decodeUint8Array(bindings.BigEndianScalar_get_bytes(ptr));
 143         }
 144     public BigEndianScalar(byte[] scalar_bytes) : base(bindings.BigEndianScalar_new(InternalUtils.encodeUint8Array(scalar_bytes))) {
 145                 this.scalar_bytes = InternalUtils.decodeUint8Array(bindings.BigEndianScalar_get_bytes(ptr));
 146         }
 147
 148         ~BigEndianScalar() {
 149                 if (ptr != 0) { bindings.BigEndianScalar_free(ptr); }
 150         }
 151 }"""
 152
 153
 154         self.c_file_pfx = """
 155 // On OSX jlong (ie long long) is not equivalent to int64_t, so we override here
 156 #define int64_t jlong
 157 #include <lightning.h>
 158 #include <string.h>
 159 #include <stdatomic.h>
 160 #include <stdlib.h>
 161
 162 #define LIKELY(v) __builtin_expect(!!(v), 1)
 163 #define UNLIKELY(v) __builtin_expect(!!(v), 0)
 164
 165 """
 166
 167         self.c_file_pfx = self.c_file_pfx + "#include <stdio.h>\n#define DEBUG_PRINT(...) fprintf(stderr, __VA_ARGS__)\n"
 168
 169         if not DEBUG or sys.platform == "darwin":
 170             self.c_file_pfx = self.c_file_pfx + """#define do_MALLOC(a, _b, _c) malloc(a)
 171 #define MALLOC(a, _) malloc(a)
 172 #define FREE(p) if ((uint64_t)(p) > 4096) { free(p); }
 173 #define CHECK_ACCESS(p)
 174 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v)
 175 """
 176         if not DEBUG:
 177             self.c_file_pfx += """#define DO_ASSERT(a) (void)(a)
 178 #define CHECK(a)
 179 """
 180         if DEBUG:
 181             self.c_file_pfx = self.c_file_pfx + """#include <assert.h>
 182 // Always run a, then assert it is true:
 183 #define DO_ASSERT(a) do { bool _assert_val = (a); assert(_assert_val); } while(0)
 184 // Assert a is true or do nothing
 185 #define CHECK(a) DO_ASSERT(a)
 186
 187 void __attribute__((constructor)) debug_log_version() {
 188         if (check_get_ldk_version() == NULL)
 189                 DEBUG_PRINT("LDK version did not match the header we built against\\n");
 190         if (check_get_ldk_bindings_version() == NULL)
 191                 DEBUG_PRINT("LDK C Bindings version did not match the header we built against\\n");
 192 }
 193 """
 194
 195             if sys.platform != "darwin":
 196                 self.c_file_pfx += """
 197 // Running a leak check across all the allocations and frees of the JDK is a mess,
 198 // so instead we implement our own naive leak checker here, relying on the -wrap
 199 // linker option to wrap malloc/calloc/realloc/free, tracking everyhing allocated
 200 // and free'd in Rust or C across the generated bindings shared library.
 201 #include <threads.h>
 202 """
 203
 204                 self.c_file_pfx = self.c_file_pfx + "#include <execinfo.h>\n"
 205                 self.c_file_pfx = self.c_file_pfx + """
 206 #include <unistd.h>
 207 #include <pthread.h>
 208 static pthread_mutex_t allocation_mtx;
 209
 210 void __attribute__((constructor)) init_mtx() {
 211         DO_ASSERT(!pthread_mutex_init(&allocation_mtx, NULL));
 212 }
 213
 214 #define BT_MAX 128
 215 typedef struct allocation {
 216         struct allocation* next;
 217         void* ptr;
 218         const char* struct_name;
 219         void* bt[BT_MAX];
 220         int bt_len;
 221         unsigned long alloc_len;
 222 } allocation;
 223 static allocation* allocation_ll = NULL;
 224
 225 void* __real_malloc(size_t len);
 226 void* __real_calloc(size_t nmemb, size_t len);
 227 static void new_allocation(void* res, const char* struct_name, size_t len) {
 228         allocation* new_alloc = __real_malloc(sizeof(allocation));
 229         new_alloc->ptr = res;
 230         new_alloc->struct_name = struct_name;
 231         new_alloc->bt_len = backtrace(new_alloc->bt, BT_MAX);
 232         new_alloc->alloc_len = len;
 233         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 234         new_alloc->next = allocation_ll;
 235         allocation_ll = new_alloc;
 236         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 237 }
 238 static void* do_MALLOC(size_t len, const char* struct_name, int lineno) {
 239         void* res = __real_malloc(len);
 240         new_allocation(res, struct_name, lineno);
 241         return res;
 242 }
 243 #define MALLOC(len, struct_name) do_MALLOC(len, struct_name, __LINE__)
 244
 245 void __real_free(void* ptr);
 246 static void alloc_freed(void* ptr) {
 247         allocation* p = NULL;
 248         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 249         allocation* it = allocation_ll;
 250         while (it->ptr != ptr) {
 251                 p = it; it = it->next;
 252                 if (it == NULL) {
 253                         DEBUG_PRINT("ERROR: Tried to free unknown pointer %p at:\\n", ptr);
 254                         void* bt[BT_MAX];
 255                         int bt_len = backtrace(bt, BT_MAX);
 256                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
 257                         DEBUG_PRINT("\\n\\n");
 258                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 259                         return; // addrsan should catch malloc-unknown and print more info than we have
 260                 }
 261         }
 262         if (p) { p->next = it->next; } else { allocation_ll = it->next; }
 263         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 264         DO_ASSERT(it->ptr == ptr);
 265         __real_free(it);
 266 }
 267 static void FREE(void* ptr) {
 268         if ((uint64_t)ptr <= 4096) return; // Rust loves to create pointers to the NULL page for dummys
 269         alloc_freed(ptr);
 270         __real_free(ptr);
 271 }
 272
 273 void* __wrap_malloc(size_t len) {
 274         void* res = __real_malloc(len);
 275         new_allocation(res, "malloc call", len);
 276         return res;
 277 }
 278 void* __wrap_calloc(size_t nmemb, size_t len) {
 279         void* res = __real_calloc(nmemb, len);
 280         new_allocation(res, "calloc call", len);
 281         return res;
 282 }
 283 void __wrap_free(void* ptr) {
 284         if (ptr == NULL) return;
 285         alloc_freed(ptr);
 286         __real_free(ptr);
 287 }
 288
 289 static void CHECK_ACCESS(const void* ptr) {
 290         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 291         allocation* it = allocation_ll;
 292         while (it->ptr != ptr) {
 293                 it = it->next;
 294                 if (it == NULL) {
 295                         DEBUG_PRINT("ERROR: Tried to access unknown pointer %p at:\\n", ptr);
 296                         void* bt[BT_MAX];
 297                         int bt_len = backtrace(bt, BT_MAX);
 298                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
 299                         DEBUG_PRINT("\\n\\n");
 300                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 301                         return; // addrsan should catch and print more info than we have
 302                 }
 303         }
 304         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 305 }
 306 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v) \\
 307         if (v.is_owned && v.inner != NULL) { \\
 308                 const void *p = __unmangle_inner_ptr(v.inner); \\
 309                 if (p != NULL) { \\
 310                         CHECK_ACCESS(p); \\
 311                 } \\
 312         }
 313
 314 void* __real_realloc(void* ptr, size_t newlen);
 315 void* __wrap_realloc(void* ptr, size_t len) {
 316         if (ptr != NULL) alloc_freed(ptr);
 317         void* res = __real_realloc(ptr, len);
 318         new_allocation(res, "realloc call", len);
 319         return res;
 320 }
 321 void __wrap_reallocarray(void* ptr, size_t new_sz) {
 322         // Rust doesn't seem to use reallocarray currently
 323         DO_ASSERT(false);
 324 }
 325
 326 void __attribute__((destructor)) check_leaks() {
 327         unsigned long alloc_count = 0;
 328         unsigned long alloc_size = 0;
 329         DEBUG_PRINT("The following LDK-allocated blocks still remain.\\n");
 330         DEBUG_PRINT("Note that this is only accurate if System.GC.Collect(); GC.WaitForPendingFinalizers();\\n");
 331         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
 332         for (allocation* a = allocation_ll; a != NULL; a = a->next) {
 333                 DEBUG_PRINT("%s %p (%lu bytes) remains:\\n", a->struct_name, a->ptr, a->alloc_len);
 334                 backtrace_symbols_fd(a->bt, a->bt_len, STDERR_FILENO);
 335                 DEBUG_PRINT("\\n\\n");
 336                 alloc_count++;
 337                 alloc_size += a->alloc_len;
 338         }
 339         DEBUG_PRINT("%lu allocations remained for %lu bytes.\\n", alloc_count, alloc_size);
 340         DEBUG_PRINT("Note that this is only accurate if System.GC.Collect(); GC.WaitForPendingFinalizers()\\n");
 341         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
 342 }
 343 """
 344         self.c_file_pfx = self.c_file_pfx + """
 345
 346 // We assume that CVec_u8Z and u8slice are the same size and layout (and thus pointers to the two can be mixed)
 347 _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKu8slice), "Vec<u8> and [u8] need to have been mapped identically");
 348 _Static_assert(offsetof(LDKCVec_u8Z, data) == offsetof(LDKu8slice, data), "Vec<u8> and [u8] need to have been mapped identically");
 349 _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKu8slice, datalen), "Vec<u8> and [u8] need to have been mapped identically");
 350
 351 _Static_assert(sizeof(void*) <= 8, "Pointers must fit into 64 bits");
 352
 353 // Int types across Windows/Linux are different, so make sure we're using the right headers.
 354 _Static_assert(sizeof(void*) == sizeof(uintptr_t), "stdints must be correct");
 355 _Static_assert(sizeof(void*) == sizeof(intptr_t), "stdints must be correct");
 356 _Static_assert(sizeof(uint64_t) == 8, "stdints must be correct");
 357 _Static_assert(sizeof(int64_t) == 8, "stdints must be correct");
 358 _Static_assert(sizeof(uint32_t) == 4, "stdints must be correct");
 359 _Static_assert(sizeof(int32_t) == 4, "stdints must be correct");
 360 _Static_assert(sizeof(uint16_t) == 2, "stdints must be correct");
 361 _Static_assert(sizeof(int16_t) == 2, "stdints must be correct");
 362 _Static_assert(sizeof(uint8_t) == 1, "stdints must be correct");
 363 _Static_assert(sizeof(int8_t) == 1, "stdints must be correct");
 364
 365 #define DECL_ARR_TYPE(ty, name) \\
 366         struct name##array { \\
 367                 uint64_t arr_len; /* uint32_t would suffice but we want to align uint64_ts as well */ \\
 368                 ty elems[]; \\
 369         }; \\
 370         typedef struct name##array * name##Array; \\
 371         static inline name##Array init_##name##Array(size_t arr_len, int lineno) { \\
 372                 name##Array arr = (name##Array)do_MALLOC(arr_len * sizeof(ty) + sizeof(uint64_t), #name" array init", lineno); \\
 373                 arr->arr_len = arr_len; \\
 374                 return arr; \\
 375         }
 376
 377 DECL_ARR_TYPE(int64_t, int64_t);
 378 DECL_ARR_TYPE(uint64_t, uint64_t);
 379 DECL_ARR_TYPE(int8_t, int8_t);
 380 DECL_ARR_TYPE(int16_t, int16_t);
 381 DECL_ARR_TYPE(uint32_t, uint32_t);
 382 DECL_ARR_TYPE(void*, ptr);
 383 DECL_ARR_TYPE(char, char);
 384 typedef charArray jstring;
 385
 386 static inline jstring str_ref_to_cs(const char* chars, size_t len) {
 387         charArray arr = init_charArray(len, __LINE__);
 388         memcpy(arr->elems, chars, len);
 389         return arr;
 390 }
 391 static inline LDKStr str_ref_to_owned_c(const jstring str) {
 392         char* newchars = MALLOC(str->arr_len + 1, "String chars");
 393         memcpy(newchars, str->elems, str->arr_len);
 394         newchars[str->arr_len] = 0;
 395         LDKStr res = {
 396                 .chars = newchars,
 397                 .len = str->arr_len,
 398                 .chars_is_owned = true
 399         };
 400         return res;
 401 }
 402
 403 typedef bool jboolean;
 404
 405 int64_t CS_LDK_allocate_buffer(int64_t len) {
 406         return (int64_t)MALLOC(len, "C#-requested buffer");
 407 }
 408
 409 void CS_LDK_free_buffer(int64_t buf) {
 410         FREE((void*)buf);
 411 }
 412
 413 jstring CS_LDK_get_ldk_c_bindings_version() {
 414         return str_ref_to_cs(check_get_ldk_bindings_version(), strlen(check_get_ldk_bindings_version()));
 415 }
 416 jstring CS_LDK_get_ldk_version() {
 417         return str_ref_to_cs(check_get_ldk_version(), strlen(check_get_ldk_version()));
 418 }
 419 #include "version.c"
 420 """
 421         self.c_version_file = """const char* CS_LDK_get_lib_version_string() {
 422         return "<git_version_ldk_garbagecollected>";
 423 }"""
 424
 425         self.hu_struct_file_prefix = """using org.ldk.impl;
 426 using org.ldk.enums;
 427 using org.ldk.util;
 428 using System;
 429
 430 namespace org { namespace ldk { namespace structs {
 431
 432 """
 433         self.hu_struct_file_suffix = "} } }\n"
 434         self.c_fn_args_pfx = ""
 435         self.c_fn_ty_pfx = ""
 436         self.file_ext = ".cs"
 437         self.ptr_c_ty = "int64_t"
 438         self.ptr_native_ty = "long"
 439         self.u128_native_ty = "UInt128"
 440         self.usize_c_ty = "int64_t"
 441         self.usize_native_ty = "long"
 442         self.native_zero_ptr = "0"
 443         self.unitary_enum_c_ty = "int32_t"
 444         self.ptr_arr = "ptrArray"
 445         self.is_arr_some_check = ("", " != NULL")
 446         self.get_native_arr_len_call = ("", "->arr_len")
 447
 448         self.bindings_footer_wip = "\tstatic bindings() {\n"
 449     def bindings_footer(self):
 450         return ""
 451
 452     def native_meth_decl(self, meth_name, ret_ty_str):
 453         return "\t[DllImport (\"ldkcsharp\", EntryPoint=\"CS_LDK_" + meth_name + "\")] public static extern " + ret_ty_str + " " + meth_name
 454
 455     def c_fn_name_define_pfx(self, fn_name, have_args):
 456         return " CS_LDK_" + fn_name + "("
 457
 458     def release_native_arr_ptr_call(self, ty_info, arr_var, arr_ptr_var):
 459         return None
 460     def create_native_arr_call(self, arr_len, ty_info):
 461         if ty_info.c_ty == "ptrArray":
 462             assert ty_info.rust_obj == "LDKCVec_U5Z" or (ty_info.subty is not None and (ty_info.subty.c_ty.endswith("Array") or ty_info.subty.rust_obj == "LDKStr"))
 463         return "init_" + ty_info.c_ty + "(" + arr_len + ", __LINE__)"
 464     def set_native_arr_contents(self, arr_name, arr_len, ty_info):
 465         if ty_info.c_ty == "int8_tArray":
 466             return ("memcpy(" + arr_name + "->elems, ", ", " + arr_len + ")")
 467         elif ty_info.c_ty == "int16_tArray":
 468             return ("memcpy(" + arr_name + "->elems, ", ", " + arr_len + " * 2)")
 469         else:
 470             assert False
 471     def get_native_arr_contents(self, arr_name, dest_name, arr_len, ty_info, copy):
 472         if ty_info.c_ty == "int8_tArray" or ty_info.c_ty == "int16_tArray":
 473             if copy:
 474                 byte_len = arr_len
 475                 if ty_info.c_ty == "int16_tArray":
 476                     byte_len = arr_len + " * 2"
 477                 return "memcpy(" + dest_name + ", " + arr_name + "->elems, " + byte_len + "); FREE(" + arr_name + ")"
 478         assert not copy
 479         if ty_info.c_ty == "ptrArray":
 480             return "(void*) " + arr_name + "->elems"
 481         else:
 482             return arr_name + "->elems"
 483     def get_native_arr_elem(self, arr_name, idxc, ty_info):
 484         assert False # Only called if above is None
 485     def get_native_arr_ptr_call(self, ty_info):
 486         if ty_info.subty is not None:
 487             return "(" + ty_info.subty.c_ty + "*)(((uint8_t*)", ") + 8)"
 488         return "(" + ty_info.c_ty + "*)(((uint8_t*)", ") + 8)"
 489     def get_native_arr_entry_call(self, ty_info, arr_name, idxc, entry_access):
 490         return None
 491     def cleanup_native_arr_ref_contents(self, arr_name, dest_name, arr_len, ty_info):
 492         if ty_info.c_ty == "int8_tArray":
 493             return "FREE(" + arr_name + ");"
 494         else:
 495             return "FREE(" + arr_name + ")"
 496
 497     def map_hu_array_elems(self, arr_name, conv_name, arr_ty, elem_ty, is_nullable):
 498         if elem_ty.java_hu_ty == "UInt5":
 499             return "InternalUtils.convUInt5Array(" + arr_name + ")"
 500         elif elem_ty.java_hu_ty == "WitnessVersion":
 501             return "InternalUtils.convWitnessVersionArray(" + arr_name + ")"
 502         else:
 503             return "InternalUtils.mapArray(" + arr_name + ", " + conv_name + " => " + elem_ty.from_hu_conv[0] + ")"
 504
 505     def str_ref_to_native_call(self, var_name, str_len):
 506         return "str_ref_to_cs(" + var_name + ", " + str_len + ")"
 507     def str_ref_to_c_call(self, var_name):
 508         return "str_ref_to_owned_c(" + var_name + ")"
 509     def str_to_hu_conv(self, var_name):
 510         return "string " + var_name + "_conv = InternalUtils.decodeString(" + var_name + ");"
 511     def str_from_hu_conv(self, var_name):
 512         return ("InternalUtils.encodeString(" + var_name + ")", "")
 513
 514     def init_str(self):
 515         ret = ""
 516         for fn_suffix in self.function_ptrs:
 517             cret = self.function_ptrs[fn_suffix]["ret"][1]
 518             cargs = self.function_ptrs[fn_suffix]["args"][1]
 519             ret += f"""
 520 typedef {cret} (*invoker_{fn_suffix})(int obj_ptr, int fn_id{cargs});
 521 static invoker_{fn_suffix} js_invoke_function_{fn_suffix};
 522 int CS_LDK_register_{fn_suffix}_invoker(invoker_{fn_suffix} invoker) {{
 523         js_invoke_function_{fn_suffix} = invoker;
 524         return 0;
 525 }}
 526 """
 527
 528         return ret
 529
 530     def var_decl_statement(self, ty_string, var_name, statement):
 531         return ty_string + " " + var_name + " = " + statement
 532
 533     def get_java_arr_len(self, arr_name):
 534         return "InternalUtils.getArrayLength(" + arr_name + ")"
 535
 536     def get_java_arr_elem(self, elem_ty, arr_name, idx):
 537         if elem_ty.c_ty == "int64_t" or elem_ty.c_ty == "uint64_t" or elem_ty.c_ty.endswith("Array") or elem_ty.c_ty == "uintptr_t":
 538             return "InternalUtils.getU64ArrayElem(" + arr_name + ", " + idx + ")"
 539         elif elem_ty.rust_obj == "LDKU5":
 540             return "InternalUtils.getU8ArrayElem(" + arr_name + ", " + idx + ")"
 541         elif elem_ty.rust_obj == "LDKStr":
 542             return "InternalUtils.getU32ArrayElem(" + arr_name + ", " + idx + ")"
 543         else:
 544             assert False
 545
 546     def constr_hu_array(self, ty_info, arr_len):
 547         base_ty = ty_info.subty.java_hu_ty.split("[")[0].split("<")[0]
 548         conv = "new " + base_ty + "[" + arr_len + "]"
 549         if "[" in ty_info.subty.java_hu_ty.split("<")[0]:
 550             # Do a bit of a dance to move any excess [] to the end
 551             conv += "[" + ty_info.subty.java_hu_ty.split("<")[0].split("[")[1]
 552         return conv
 553     def cleanup_converted_native_array(self, ty_info, arr_name):
 554         return "bindings.free_buffer(" + arr_name + ");"
 555
 556     def primitive_arr_from_hu(self, arr_ty, fixed_len, arr_name):
 557         mapped_ty = arr_ty.subty
 558         inner = arr_name
 559         if arr_ty.rust_obj == "LDKU128":
 560             return ("InternalUtils.encodeUint8Array(" + arr_name + ".getLEBytes())", "")
 561         if fixed_len is not None:
 562             inner = "InternalUtils.check_arr_len(" + arr_name + ", " + fixed_len + ")"
 563         if mapped_ty.c_ty.endswith("Array"):
 564             return ("InternalUtils.encodeUint64Array(" + inner + ")", "")
 565         elif mapped_ty.c_ty == "uint8_t" or mapped_ty.c_ty == "int8_t":
 566             return ("InternalUtils.encodeUint8Array(" + inner + ")", "")
 567         elif mapped_ty.c_ty == "uint16_t" or mapped_ty.c_ty == "int16_t":
 568             return ("InternalUtils.encodeUint16Array(" + inner + ")", "")
 569         elif mapped_ty.c_ty == "uint32_t":
 570             return ("InternalUtils.encodeUint32Array(" + inner + ")", "")
 571         elif mapped_ty.c_ty == "int64_t" or mapped_ty.c_ty == "uint64_t" or mapped_ty.rust_obj == "LDKStr":
 572             return ("InternalUtils.encodeUint64Array(" + inner + ")", "")
 573         else:
 574             print(mapped_ty.c_ty)
 575             assert False
 576
 577     def primitive_arr_to_hu(self, arr_ty, fixed_len, arr_name, conv_name):
 578         mapped_ty = arr_ty.subty
 579         if arr_ty.rust_obj == "LDKU128":
 580             return "org.ldk.util.UInt128 " + conv_name + " = new org.ldk.util.UInt128(" + arr_name + ");"
 581         elif mapped_ty.c_ty == "uint8_t" or mapped_ty.c_ty == "int8_t":
 582             return "byte[] " + conv_name + " = InternalUtils.decodeUint8Array(" + arr_name + ");"
 583         elif mapped_ty.c_ty == "uint16_t" or mapped_ty.c_ty == "int16_t":
 584             return "short[] " + conv_name + " = InternalUtils.decodeUint16Array(" + arr_name + ");"
 585         elif mapped_ty.c_ty == "uint64_t" or mapped_ty.c_ty == "int64_t":
 586             return "long[] " + conv_name + " = InternalUtils.decodeUint64Array(" + arr_name + ");"
 587         else:
 588             assert False
 589
 590     def java_arr_ty_str(self, elem_ty_str):
 591         return "long"
 592
 593     def for_n_in_range(self, n, minimum, maximum):
 594         return "for (int " + n + " = " + minimum + "; " + n + " < " + maximum + "; " + n + "++) {"
 595     def for_n_in_arr(self, n, arr_name, arr_elem_ty):
 596         return ("foreach (" + arr_elem_ty.java_hu_ty + " " + n + " in " + arr_name + ") { ", " }")
 597
 598     def get_ptr(self, var):
 599         return var + ".ptr"
 600     def set_null_skip_free(self, var):
 601         return var + ".ptr" + " = 0;"
 602
 603     def add_ref(self, holder, referent):
 604         return "if (" + holder + " != null) { " + holder + ".ptrs_to.AddLast(" + referent + "); }"
 605
 606     def fully_qualified_hu_ty_path(self, ty):
 607         if ty.java_fn_ty_arg.startswith("L") and ty.java_fn_ty_arg.endswith(";"):
 608             return ty.java_hu_ty
 609         if ty.java_hu_ty == "UnqualifiedError" or ty.java_hu_ty == "UInt128" or ty.java_hu_ty == "UInt5" or ty.java_hu_ty == "WitnessVersion":
 610             return "org.ldk.util." + ty.java_hu_ty
 611         if not ty.is_native_primitive and ty.rust_obj is not None and not "[]" in ty.java_hu_ty:
 612             return "org.ldk.structs." + ty.java_hu_ty
 613         return ty.java_hu_ty
 614
 615     def native_c_unitary_enum_map(self, struct_name, variants, enum_doc_comment):
 616         out_java_enum = "namespace org { namespace ldk { namespace enums {"
 617         out_java = ""
 618         out_c = ""
 619
 620         out_c = "static inline LDK" + struct_name + " LDK" + struct_name + "_from_cs(int32_t ord) {\n"
 621         out_c += "\tswitch (ord) {\n"
 622
 623         if enum_doc_comment is not None:
 624             out_java_enum += "/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
 625         out_java_enum += "public enum " + struct_name + " {\n"
 626         ord_v = 0
 627         for var, var_docs in variants:
 628             if var_docs is not None:
 629                 out_java_enum += "\t/**\n\t * " + var_docs.replace("\n", "\n\t * ") + "\n\t */\n"
 630             out_java_enum += "\t" + var + ",\n"
 631             out_c = out_c + "\t\tcase %d: return %s;\n" % (ord_v, var)
 632             ord_v = ord_v + 1
 633         out_java_enum += "}"
 634         out_c += "\t\tdefault: abort();\n"
 635         out_c += "\t}\n"
 636         out_c += "}\n"
 637
 638         out_c = out_c + "static inline int32_t LDK" + struct_name + "_to_cs(LDK" + struct_name + " val) {\n"
 639         out_c = out_c + "\tswitch (val) {\n"
 640         ord_v = 0
 641         for var, _ in variants:
 642             out_c = out_c + "\t\tcase " + var + ": return %d;\n" % ord_v
 643             ord_v = ord_v + 1
 644         out_c = out_c + "\t\tdefault: abort();\n"
 645         out_c = out_c + "\t}\n"
 646         out_c = out_c + "}\n"
 647
 648         return (out_c, out_java_enum + "} } }\n", out_java)
 649
 650     def c_unitary_enum_to_native_call(self, ty_info):
 651         return (ty_info.rust_obj + "_to_cs(", ")")
 652     def native_unitary_enum_to_c_call(self, ty_info):
 653         return (ty_info.rust_obj + "_from_cs(", ")")
 654
 655     def c_complex_enum_pfx(self, struct_name, variants, init_meth_jty_strs):
 656         out_c = ""
 657         for var in variants:
 658             out_c = out_c + "static jclass " + struct_name + "_" + var + "_class = NULL;\n"
 659             out_c = out_c + "static jmethodID " + struct_name + "_" + var + "_meth = NULL;\n"
 660         out_c += "void" + self.c_fn_name_define_pfx(struct_name.replace("_", "_1") + "_init", True) + self.c_fn_args_pfx + ") {\n"
 661         for var_name in variants:
 662             out_c += "\t" + struct_name + "_" + var_name + "_class =\n"
 663             out_c += "\t\t(*env)->NewGlobalRef(env, (*env)->FindClass(env, \"org/ldk/impl/bindings$" + struct_name + "$" + var_name + "\"));\n"
 664             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_class != NULL);\n"
 665             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"
 666             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_meth != NULL);\n"
 667         out_c = out_c + "}\n"
 668         return out_c
 669
 670     def c_complex_enum_pass_ty(self, struct_name):
 671         return "jobject"
 672
 673     def c_constr_native_complex_enum(self, struct_name, variant, c_params):
 674         ret = "(*env)->NewObject(env, " + struct_name + "_" + variant + "_class, " + struct_name + "_" + variant + "_meth"
 675         for param in c_params:
 676             ret = ret + ", " + param
 677         return ret + ")"
 678
 679     def native_c_map_trait(self, struct_name, field_var_conversions, flattened_field_var_conversions, field_function_lines, trait_doc_comment):
 680         out_typescript_bindings = ""
 681         super_instantiator = ""
 682         bindings_instantiator = ""
 683         pointer_to_adder = ""
 684         impl_constructor_arguments = ""
 685         for var in flattened_field_var_conversions:
 686             if isinstance(var, ConvInfo):
 687                 impl_constructor_arguments += f", {var.java_hu_ty} {var.arg_name}"
 688                 if var.from_hu_conv is not None:
 689                     bindings_instantiator += ", " + var.from_hu_conv[0]
 690                     if var.from_hu_conv[1] != "":
 691                         pointer_to_adder += "\t\t\t" + var.from_hu_conv[1] + ";\n"
 692                 else:
 693                     bindings_instantiator += ", " + first_to_lower(var.arg_name)
 694             else:
 695                 bindings_instantiator += ", " + first_to_lower(var[1]) + ".instance_idx"
 696                 pointer_to_adder += "\t\timpl_holder.held.ptrs_to.AddLast(" + first_to_lower(var[1]) + ");\n"
 697                 impl_constructor_arguments += f", {var[0].replace('LDK', '')}Interface {first_to_lower(var[1])}_impl"
 698
 699         super_constructor_statements = ""
 700         trait_constructor_arguments = ""
 701         for var in field_var_conversions:
 702             if isinstance(var, ConvInfo):
 703                 trait_constructor_arguments += ", " + var.arg_name
 704             else:
 705                 super_constructor_statements += "\t\t" + var[1] + " " + first_to_lower(var[1]) + " = " + var[1] + ".new_impl(" + first_to_lower(var[1]) + "_impl"
 706                 super_instantiator = ""
 707                 for suparg in var[2]:
 708                     if isinstance(suparg, ConvInfo):
 709                         super_instantiator += ", " + suparg.arg_name
 710                     else:
 711                         super_instantiator += ", " + first_to_lower(suparg[1]) + "_impl"
 712                 super_constructor_statements += super_instantiator + ");\n"
 713                 trait_constructor_arguments += ", " + first_to_lower(var[1]) + ".instance_idx"
 714                 for suparg in var[2]:
 715                     if isinstance(suparg, ConvInfo):
 716                         trait_constructor_arguments += ", " + suparg.arg_name
 717                     else:
 718                         # Blindly assume that we can just strip the first arg to build the args for the supertrait
 719                         super_constructor_statements += "\t\t" + suparg[1] + " " + first_to_lower(suparg[1]) + " = " + suparg[1] + ".new_impl(" + super_instantiator.split(", ", 1)[1] + ");\n"
 720                         trait_constructor_arguments += ", " + suparg[1]
 721
 722         # BUILD INTERFACE METHODS
 723
 724         java_trait_wrapper = "\tprivate class " + struct_name + "Holder { internal " + struct_name.replace("LDK", "") + " held; }\n"
 725         java_trait_wrapper += "\tprivate class " + struct_name + "Impl : bindings." + struct_name + " {\n"
 726         java_trait_wrapper += "\t\tinternal " + struct_name + "Impl(" + struct_name.replace("LDK", "") + "Interface arg, " + struct_name + "Holder impl_holder) { this.arg = arg; this.impl_holder = impl_holder; }\n"
 727         java_trait_wrapper += "\t\tprivate " + struct_name.replace("LDK", "") + "Interface arg;\n"
 728         java_trait_wrapper += "\t\tprivate " + struct_name + "Holder impl_holder;\n"
 729
 730         for fn_line in field_function_lines:
 731             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 732                 fn_name = fn_line.fn_name
 733                 if fn_name == "lock": # reserved symbol
 734                     fn_name = "do_lock"
 735                 java_trait_wrapper += "\t\tpublic " + fn_line.ret_ty_info.java_ty + " " + fn_name + "("
 736
 737                 for idx, arg_conv_info in enumerate(fn_line.args_ty):
 738                     if idx >= 1:
 739                         java_trait_wrapper += ", "
 740                     java_trait_wrapper += arg_conv_info.java_ty + " _" + arg_conv_info.arg_name
 741
 742                 java_trait_wrapper += ") {\n"
 743
 744                 for arg_info in fn_line.args_ty:
 745                     if arg_info.to_hu_conv is not None:
 746                         java_trait_wrapper += "\t\t\t" + arg_info.to_hu_conv.replace("\n", "\n\t\t\t").replace(arg_info.arg_name, "_" + arg_info.arg_name) + "\n"
 747
 748                 if fn_line.ret_ty_info.java_ty != "void":
 749                     java_trait_wrapper += "\t\t\t" + fn_line.ret_ty_info.java_hu_ty + " ret = arg." + fn_name + "("
 750                 else:
 751                     java_trait_wrapper += "\t\t\targ." + fn_name + "("
 752
 753                 for idx, arg_info in enumerate(fn_line.args_ty):
 754                     if idx != 0:
 755                         java_trait_wrapper += ", "
 756                     if arg_info.to_hu_conv_name is not None:
 757                         java_trait_wrapper += arg_info.to_hu_conv_name.replace(arg_info.arg_name, "_" + arg_info.arg_name)
 758                     else:
 759                         java_trait_wrapper += "_" + arg_info.arg_name
 760
 761                 java_trait_wrapper += ");\n"
 762                 java_trait_wrapper += "\t\t\t\tGC.KeepAlive(arg);\n"
 763                 if fn_line.ret_ty_info.java_ty != "void":
 764                     if fn_line.ret_ty_info.from_hu_conv is not None:
 765                         java_trait_wrapper += "\t\t\t" + fn_line.ret_ty_info.java_ty + " result = " + fn_line.ret_ty_info.from_hu_conv[0] + ";\n"
 766                         if fn_line.ret_ty_info.from_hu_conv[1] != "":
 767                             java_trait_wrapper += "\t\t\t" + fn_line.ret_ty_info.from_hu_conv[1].replace("this", "impl_holder.held") + ";\n"
 768                         java_trait_wrapper += "\t\t\treturn result;\n"
 769                     else:
 770                         java_trait_wrapper += "\t\t\treturn ret;\n"
 771                 java_trait_wrapper += "\t\t}\n"
 772         java_trait_wrapper += "\t}"
 773
 774         out_java_interface = ""
 775         java_methods = []
 776         for fn_line in field_function_lines:
 777             java_method_descriptor = ""
 778             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 779                 out_java_interface += "\t/**" + fn_line.docs.replace("\n", "\n\t * ") + "\n\t */\n"
 780                 out_java_interface += "\t" + fn_line.ret_ty_info.java_hu_ty + " " + fn_line.fn_name + "("
 781
 782                 for idx, arg_conv_info in enumerate(fn_line.args_ty):
 783                     if idx >= 1:
 784                         out_java_interface += ", "
 785                     out_java_interface += f"{arg_conv_info.java_hu_ty} {safe_arg_name(arg_conv_info.arg_name)}"
 786                     java_method_descriptor += arg_conv_info.java_fn_ty_arg
 787                 out_java_interface += f");\n"
 788                 java_method_descriptor += ")" + fn_line.ret_ty_info.java_fn_ty_arg
 789                 java_methods.append((fn_line.fn_name, java_method_descriptor))
 790
 791         formatted_trait_docs = trait_doc_comment.replace("\n", "\n * ")
 792         out_typescript_human = f"""
 793 {self.hu_struct_file_prefix}
 794
 795 /** An implementation of {struct_name.replace("LDK","")} */
 796 public interface {struct_name.replace("LDK", "")}Interface {{
 797 {out_java_interface}}}
 798
 799 /**
 800  * {formatted_trait_docs}
 801  */
 802 public class {struct_name.replace("LDK","")} : CommonBase {{
 803         internal bindings.{struct_name} bindings_instance;
 804         internal long instance_idx;
 805
 806         internal {struct_name.replace("LDK","")}(object _dummy, long ptr) : base(ptr) {{ bindings_instance = null; }}
 807         ~{struct_name.replace("LDK","")}() {{
 808                 if (ptr != 0) {{ bindings.{struct_name.replace("LDK","")}_free(ptr); }}
 809         }}
 810
 811 {java_trait_wrapper}
 812
 813         /** Creates a new instance of {struct_name.replace("LDK","")} from a given implementation */
 814         public static {struct_name.replace("LDK", "")} new_impl({struct_name.replace("LDK", "")}Interface arg{impl_constructor_arguments}) {{
 815                 {struct_name}Holder impl_holder = new {struct_name}Holder();
 816                 {struct_name}Impl impl = new {struct_name}Impl(arg, impl_holder);
 817 {super_constructor_statements}          long[] ptr_idx = bindings.{struct_name}_new(impl{bindings_instantiator});
 818
 819                 impl_holder.held = new {struct_name.replace("LDK", "")}(null, ptr_idx[0]);
 820                 impl_holder.held.instance_idx = ptr_idx[1];
 821                 impl_holder.held.bindings_instance = impl;
 822 {pointer_to_adder}              return impl_holder.held;
 823         }}
 824
 825 """
 826
 827         out_typescript_bindings += "\tpublic interface " + struct_name + " {\n"
 828         java_meths = []
 829         for fn_line in field_function_lines:
 830             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 831                 out_typescript_bindings += f"\t\t{fn_line.ret_ty_info.java_ty} {fn_line.fn_name}("
 832
 833                 for idx, arg_conv_info in enumerate(fn_line.args_ty):
 834                     if idx >= 1:
 835                         out_typescript_bindings = out_typescript_bindings + ", "
 836                     out_typescript_bindings += f"{arg_conv_info.java_ty} {safe_arg_name(arg_conv_info.arg_name)}"
 837
 838                 out_typescript_bindings += f");\n"
 839
 840         out_typescript_bindings += "\t}\n"
 841
 842         c_call_extra_args = ""
 843         native_fn_args = "long impl_idx"
 844         for var in flattened_field_var_conversions:
 845             if isinstance(var, ConvInfo):
 846                 native_fn_args += ", " + var.java_ty + " " + var.arg_name
 847             else:
 848                 native_fn_args += ", long " + var[1]
 849         out_typescript_bindings += self.native_meth_decl(struct_name + "_new", "long") + "_native(" + native_fn_args + ");\n"
 850         out_typescript_bindings += f"\tpublic static long[] {struct_name}_new({struct_name} impl"
 851         for var in flattened_field_var_conversions:
 852             if isinstance(var, ConvInfo):
 853                 out_typescript_bindings += f", {var.java_ty} {var.arg_name}"
 854                 c_call_extra_args += f", {var.arg_name}"
 855             else:
 856                 out_typescript_bindings += f", long {var[1]}"
 857                 c_call_extra_args += f", {var[1]}"
 858
 859
 860         out_typescript_bindings += f""") {{
 861                 long new_obj_idx = js_objs.Count;
 862                 int i = 0;
 863                 for (; i < js_objs.Count; i++) {{
 864                         if (js_objs[i] == null || !js_objs[i].IsAlive) {{ new_obj_idx = i; break; }}
 865                 }}
 866                 if (i == js_objs.Count) {{
 867                         js_objs.Add(new WeakReference(impl));
 868                 }} else {{
 869                         js_objs[i] = new WeakReference(impl);
 870                 }}
 871                 long[] ret = new long[2];
 872                 ret[0] = {struct_name}_new_native(i{c_call_extra_args});
 873                 ret[1] = i;
 874                 return ret;
 875         }}
 876 """
 877
 878         # Now that we've written out our java code (and created java_meths), generate C
 879         out_c = "typedef struct " + struct_name + "_JCalls {\n"
 880         out_c += "\tatomic_size_t refcnt;\n"
 881         out_c += "\tuint32_t instance_ptr;\n"
 882         for var in flattened_field_var_conversions:
 883             if isinstance(var, ConvInfo):
 884                 # We're a regular ol' field
 885                 pass
 886             else:
 887                 # We're a supertrait
 888                 out_c = out_c + "\t" + var[0] + "_JCalls* " + var[1] + ";\n"
 889         out_c = out_c + "} " + struct_name + "_JCalls;\n"
 890
 891         for fn_line in field_function_lines:
 892             if fn_line.fn_name == "free":
 893                 out_c = out_c + "static void " + struct_name + "_JCalls_free(void* this_arg) {\n"
 894                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
 895                 out_c = out_c + "\tif (atomic_fetch_sub_explicit(&j_calls->refcnt, 1, memory_order_acquire) == 1) {\n"
 896                 out_c = out_c + "\t\tFREE(j_calls);\n"
 897                 out_c = out_c + "\t}\n}\n"
 898
 899         for idx, fn_line in enumerate(field_function_lines):
 900             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 901                 assert fn_line.ret_ty_info.ty_info.get_full_rust_ty()[1] == ""
 902                 out_c = out_c + fn_line.ret_ty_info.ty_info.get_full_rust_ty()[0] + " " + fn_line.fn_name + "_" + struct_name + "_jcall("
 903                 if fn_line.self_is_const:
 904                     out_c = out_c + "const void* this_arg"
 905                 else:
 906                     out_c = out_c + "void* this_arg"
 907
 908                 for idx, arg in enumerate(fn_line.args_ty):
 909                     out_c = out_c + ", " + arg.ty_info.get_full_rust_ty()[0] + " " + arg.arg_name + arg.ty_info.get_full_rust_ty()[1]
 910
 911                 out_c = out_c + ") {\n"
 912                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
 913
 914                 for arg_info in fn_line.args_ty:
 915                     if arg_info.ret_conv is not None:
 916                         out_c = out_c + "\t" + arg_info.ret_conv[0].replace('\n', '\n\t')
 917                         out_c = out_c + arg_info.arg_name
 918                         out_c = out_c + arg_info.ret_conv[1].replace('\n', '\n\t') + "\n"
 919
 920                 ty_to_c = lambda jty, ty: "b" if jty == "bool" else "c" if jty == "char" else "s" if jty == "short" else "i" if jty == "int" else "l" if jty == "long" else "void" if jty == "void" else jty
 921
 922                 fn_java_callback_args = ""
 923                 fn_c_callback_args = ""
 924                 fn_callback_call_args = ""
 925                 fn_suffix = ty_to_c(fn_line.ret_ty_info.java_ty, fn_line.ret_ty_info) + "_"
 926                 idx = 0
 927                 for arg_info in fn_line.args_ty:
 928                     fn_suffix += ty_to_c(arg_info.java_ty, arg_info)
 929                     fn_java_callback_args += ", " + arg_info.java_ty + " " + chr(ord("a") + idx)
 930                     if arg_info.c_ty.endswith("Array") or arg_info.c_ty == "jstring":
 931                         fn_c_callback_args += ", int64_t " + chr(ord("a") + idx)
 932                     else:
 933                         fn_c_callback_args += ", " + arg_info.c_ty + " " + chr(ord("a") + idx)
 934                     if idx != 0:
 935                         fn_callback_call_args += ", "
 936                     fn_callback_call_args += chr(ord("a") + idx)
 937                     idx += 1
 938                 if fn_line.ret_ty_info.c_ty.endswith("Array"):
 939                     out_c += "\t" + fn_line.ret_ty_info.c_ty + " ret = (" + fn_line.ret_ty_info.c_ty + ")"
 940                     out_c += "js_invoke_function_" + fn_suffix + "(j_calls->instance_ptr, " + str(self.function_ptr_counter)
 941                 elif fn_line.ret_ty_info.java_ty == "void":
 942                     out_c = out_c + "\tjs_invoke_function_" + fn_suffix + "(j_calls->instance_ptr, " + str(self.function_ptr_counter)
 943                 elif fn_line.ret_ty_info.java_hu_ty == "string":
 944                     out_c += "\tjstring ret = (jstring)js_invoke_function_" + fn_suffix + "(j_calls->instance_ptr, " + str(self.function_ptr_counter)
 945                 elif fn_line.ret_ty_info.arg_conv is None:
 946                     out_c += "\treturn js_invoke_function_" + fn_suffix + "(j_calls->instance_ptr, " + str(self.function_ptr_counter)
 947                 else:
 948                     out_c += "\tuint64_t ret = js_invoke_function_" + fn_suffix + "(j_calls->instance_ptr, " + str(self.function_ptr_counter)
 949
 950                 if fn_suffix not in self.function_ptrs:
 951                     caller_ret_c_ty = fn_line.ret_ty_info.c_ty
 952                     if fn_line.ret_ty_info.c_ty.endswith("Array") or fn_line.ret_ty_info.c_ty == "jstring":
 953                         caller_ret_c_ty = "int64_t"
 954                     self.function_ptrs[fn_suffix] = {"args": [fn_java_callback_args, fn_c_callback_args], "ret": [fn_line.ret_ty_info.java_ty, caller_ret_c_ty]}
 955                 self.function_ptrs[fn_suffix][self.function_ptr_counter] = (struct_name, fn_line.fn_name, fn_callback_call_args)
 956                 self.function_ptr_counter += 1
 957
 958                 for idx, arg_info in enumerate(fn_line.args_ty):
 959                     if arg_info.ret_conv is not None:
 960                         if arg_info.c_ty.endswith("Array") or arg_info.c_ty == "jstring":
 961                             out_c += ", (int64_t)" + arg_info.ret_conv_name
 962                         else:
 963                             out_c += ", " + arg_info.ret_conv_name
 964                     else:
 965                         assert False # TODO: Would we need some conversion here?
 966                         out_c += ", (int64_t)" + arg_info.arg_name
 967                 out_c = out_c + ");\n"
 968                 if fn_line.ret_ty_info.arg_conv is not None:
 969                     out_c = out_c + "\t" + fn_line.ret_ty_info.arg_conv.replace("\n", "\n\t") + "\n\treturn " + fn_line.ret_ty_info.arg_conv_name + ";\n"
 970
 971                 out_c = out_c + "}\n"
 972
 973         # Write out a clone function whether we need one or not, as we use them in moving to rust
 974         out_c = out_c + "static void " + struct_name + "_JCalls_cloned(" + struct_name + "* new_obj) {\n"
 975         out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) new_obj->this_arg;\n"
 976         out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->refcnt, 1, memory_order_release);\n"
 977         for var in flattened_field_var_conversions:
 978             if not isinstance(var, ConvInfo):
 979                 out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->" + var[2].replace(".", "->") + "->refcnt, 1, memory_order_release);\n"
 980         out_c = out_c + "}\n"
 981
 982         out_c = out_c + "static inline " + struct_name + " " + struct_name + "_init (int64_t o"
 983         for var in flattened_field_var_conversions:
 984             if isinstance(var, ConvInfo):
 985                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
 986             else:
 987                 out_c = out_c + ", int64_t " + var[1]
 988         out_c = out_c + ") {\n"
 989
 990         out_c = out_c + "\t" + struct_name + "_JCalls *calls = MALLOC(sizeof(" + struct_name + "_JCalls), \"" + struct_name + "_JCalls\");\n"
 991         out_c = out_c + "\tatomic_init(&calls->refcnt, 1);\n"
 992         out_c = out_c + "\tcalls->instance_ptr = o;\n"
 993
 994         for (fn_name, java_meth_descr) in java_meths:
 995             if fn_name != "free" and fn_name != "cloned":
 996                 out_c = out_c + "\tcalls->" + fn_name + "_meth = (*env)->GetMethodID(env, c, \"" + fn_name + "\", \"" + java_meth_descr + "\");\n"
 997                 out_c = out_c + "\tCHECK(calls->" + fn_name + "_meth != NULL);\n"
 998
 999         for var in flattened_field_var_conversions:
1000             if isinstance(var, ConvInfo) and var.arg_conv is not None:
1001                 out_c = out_c + "\n\t" + var.arg_conv.replace("\n", "\n\t") +"\n"
1002         out_c = out_c + "\n\t" + struct_name + " ret = {\n"
1003         out_c = out_c + "\t\t.this_arg = (void*) calls,\n"
1004         for fn_line in field_function_lines:
1005             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
1006                 out_c = out_c + "\t\t." + fn_line.fn_name + " = " + fn_line.fn_name + "_" + struct_name + "_jcall,\n"
1007             elif fn_line.fn_name == "free":
1008                 out_c = out_c + "\t\t.free = " + struct_name + "_JCalls_free,\n"
1009             else:
1010                 out_c = out_c + "\t\t.cloned = " + struct_name + "_JCalls_cloned,\n"
1011         for var in field_var_conversions:
1012             if isinstance(var, ConvInfo):
1013                 if var.arg_conv_name is not None:
1014                     out_c = out_c + "\t\t." + var.arg_name + " = " + var.arg_conv_name + ",\n"
1015                     out_c = out_c + "\t\t.set_" + var.arg_name + " = NULL,\n"
1016                 else:
1017                     out_c = out_c + "\t\t." + var.var_name + " = " + var.var_name + ",\n"
1018                     out_c = out_c + "\t\t.set_" + var.var_name + " = NULL,\n"
1019             else:
1020                 out_c += "\t\t." + var[1] + " = " + var[0] + "_init(" + var[1]
1021                 for suparg in var[2]:
1022                     if isinstance(suparg, ConvInfo):
1023                         out_c += ", " + suparg.arg_name
1024                     else:
1025                         out_c += ", " + suparg[1]
1026                 out_c += "),\n"
1027         out_c = out_c + "\t};\n"
1028         for var in flattened_field_var_conversions:
1029             if not isinstance(var, ConvInfo):
1030                 out_c = out_c + "\tcalls->" + var[1] + " = ret." + var[2] + ".this_arg;\n"
1031         out_c = out_c + "\treturn ret;\n"
1032         out_c = out_c + "}\n"
1033
1034         out_c = out_c + self.c_fn_ty_pfx + "uint64_t " + self.c_fn_name_define_pfx(struct_name + "_new", True) + "int32_t o"
1035         for var in flattened_field_var_conversions:
1036             if isinstance(var, ConvInfo):
1037                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
1038             else:
1039                 out_c = out_c + ", int32_t " + var[1]
1040         out_c = out_c + ") {\n"
1041         out_c = out_c + "\t" + struct_name + " *res_ptr = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n"
1042         out_c = out_c + "\t*res_ptr = " + struct_name + "_init(o"
1043         for var in flattened_field_var_conversions:
1044             if isinstance(var, ConvInfo):
1045                 out_c = out_c + ", " + var.arg_name
1046             else:
1047                 out_c = out_c + ", " + var[1]
1048         out_c = out_c + ");\n"
1049         out_c = out_c + "\treturn tag_ptr(res_ptr, true);\n"
1050         out_c = out_c + "}\n"
1051
1052         return (out_typescript_bindings, out_typescript_human, out_c)
1053
1054     def trait_struct_inc_refcnt(self, ty_info):
1055         base_conv = "\nif (" + ty_info.var_name + "_conv.free == " + ty_info.rust_obj + "_JCalls_free) {\n"
1056         base_conv = base_conv + "\t// If this_arg is a JCalls struct, then we need to increment the refcnt in it.\n"
1057         base_conv = base_conv + "\t" + ty_info.rust_obj + "_JCalls_cloned(&" + ty_info.var_name + "_conv);\n}"
1058         return base_conv
1059
1060     def map_complex_enum(self, struct_name, variant_list, camel_to_snake, enum_doc_comment):
1061         bindings_type = struct_name.replace("LDK", "")
1062         java_hu_type = struct_name.replace("LDK", "").replace("COption", "Option")
1063
1064         out_java_enum = ""
1065         out_java = ""
1066         out_c = ""
1067
1068         out_java_enum += (self.hu_struct_file_prefix)
1069
1070         java_hu_class = "/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
1071         java_hu_class += "public class " + java_hu_type + " : CommonBase {\n"
1072         java_hu_class += f"\tprotected {java_hu_type}(object _dummy, long ptr) : base(ptr)" + " { }\n"
1073         java_hu_class += "\t~" + java_hu_type + "() {\n"
1074         java_hu_class += "\t\tif (ptr != 0) { bindings." + bindings_type + "_free(ptr); }\n"
1075         java_hu_class += "\t}\n\n"
1076         java_hu_class += f"\tinternal static {java_hu_type} constr_from_ptr(long ptr) {{\n"
1077         java_hu_class += f"\t\tlong raw_ty = bindings." + struct_name + "_ty_from_ptr(ptr);\n"
1078         out_c += self.c_fn_ty_pfx + "uint32_t" + self.c_fn_name_define_pfx(struct_name + "_ty_from_ptr", True) + self.ptr_c_ty + " ptr) {\n"
1079         out_c += "\t" + struct_name + " *obj = (" + struct_name + "*)untag_ptr(ptr);\n"
1080         out_c += "\tswitch(obj->tag) {\n"
1081         java_hu_class += "\t\tswitch (raw_ty) {\n"
1082         java_hu_subclasses = ""
1083
1084         var_idx = 0
1085         for var in variant_list:
1086             java_hu_subclasses += "\t/** A " + java_hu_type + " of type " + var.var_name + " */\n"
1087             java_hu_subclasses += "\tpublic class " + java_hu_type + "_" + var.var_name + " : " + java_hu_type + " {\n"
1088             java_hu_class += f"\t\t\tcase {var_idx}: "
1089             java_hu_class += "return new " + java_hu_type + "_" + var.var_name + "(ptr);\n"
1090             out_c += f"\t\tcase {struct_name}_{var.var_name}: return {var_idx};\n"
1091             hu_conv_body = ""
1092             for idx, (field_ty, field_docs) in enumerate(var.fields):
1093                 if field_docs is not None:
1094                     java_hu_subclasses += "\t\t/**\n\t\t * " + field_docs.replace("\n", "\n\t\t * ") + "\n\t\t */\n"
1095                 java_hu_subclasses += f"\t\tpublic {field_ty.java_hu_ty} {field_ty.arg_name};\n"
1096                 if field_ty.to_hu_conv is not None:
1097                     hu_conv_body += f"\t\t\t{field_ty.java_ty} {field_ty.arg_name} = bindings.{struct_name}_{var.var_name}_get_{field_ty.arg_name}(ptr);\n"
1098                     hu_conv_body += f"\t\t\t" + field_ty.to_hu_conv.replace("\n", "\n\t\t\t") + "\n"
1099                     hu_conv_body += f"\t\t\tthis." + field_ty.arg_name + " = " + field_ty.to_hu_conv_name + ";\n"
1100                 else:
1101                     hu_conv_body += f"\t\t\tthis.{field_ty.arg_name} = bindings.{struct_name}_{var.var_name}_get_{field_ty.arg_name}(ptr);\n"
1102             java_hu_subclasses += "\t\tinternal " + java_hu_type + "_" + var.var_name + "(long ptr) : base(null, ptr) {\n"
1103             java_hu_subclasses += hu_conv_body
1104             java_hu_subclasses += "\t\t}\n\t}\n"
1105             var_idx += 1
1106         java_hu_class += "\t\t\tdefault:\n\t\t\t\tthrow new ArgumentException(\"Impossible enum variant\");\n\t\t}\n\t}\n\n"
1107         out_java += self.native_meth_decl(struct_name + "_ty_from_ptr", "long") + "(long ptr);\n"
1108         out_c += ("\t\tdefault: abort();\n")
1109         out_c += ("\t}\n}\n")
1110
1111         for var in variant_list:
1112             for idx, (field_map, _) in enumerate(var.fields):
1113                 fn_name = f"{struct_name}_{var.var_name}_get_{field_map.arg_name}"
1114                 out_c += self.c_fn_ty_pfx + field_map.c_ty + self.c_fn_name_define_pfx(fn_name, True) + self.ptr_c_ty + " ptr) {\n"
1115                 out_c += "\t" + struct_name + " *obj = (" + struct_name + "*)untag_ptr(ptr);\n"
1116                 out_c += f"\tCHECK(obj->tag == {struct_name}_{var.var_name});\n"
1117                 if field_map.ret_conv is not None:
1118                     out_c += ("\t" + field_map.ret_conv[0].replace("\n", "\n\t"))
1119                     if var.tuple_variant:
1120                         out_c += "obj->" + camel_to_snake(var.var_name)
1121                     else:
1122                         out_c += "obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name
1123                     out_c += (field_map.ret_conv[1].replace("\n", "\n\t\t\t") + "\n")
1124                     out_c += "\treturn " + field_map.ret_conv_name + ";\n"
1125                 else:
1126                     if var.tuple_variant:
1127                         out_c += "\treturn " + "obj->" + camel_to_snake(var.var_name) + ";\n"
1128                     else:
1129                         out_c += "\treturn " + "obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name + ";\n"
1130                 out_c += "}\n"
1131                 out_java += self.native_meth_decl(fn_name, field_map.java_ty) + "(long ptr);\n"
1132         out_java_enum += java_hu_class
1133         out_java_enum += java_hu_subclasses
1134         return (out_java, out_java_enum, out_c)
1135
1136     def map_opaque_struct(self, struct_name, struct_doc_comment):
1137         out_opaque_struct_human = ""
1138         out_opaque_struct_human += self.hu_struct_file_prefix
1139         out_opaque_struct_human += "\n/**\n * " + struct_doc_comment.replace("\n", "\n * ") + "\n */\n"
1140         hu_name = struct_name.replace("LDKC2Tuple", "TwoTuple").replace("LDKC3Tuple", "ThreeTuple").replace("LDK", "")
1141         out_opaque_struct_human += ("public class " + hu_name + " : CommonBase")
1142         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1143             out_opaque_struct_human += (", IDisposable")
1144         out_opaque_struct_human += (" {\n")
1145         out_opaque_struct_human += ("\tinternal " + hu_name + "(object _dummy, long ptr) : base(ptr) { }\n")
1146         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1147             out_opaque_struct_human += ("\tpublic void Dispose() {\n")
1148         else:
1149             out_opaque_struct_human += ("\t~" + hu_name + "() {\n")
1150         out_opaque_struct_human += ("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); }\n")
1151         out_opaque_struct_human += ("\t}\n\n")
1152         return out_opaque_struct_human
1153
1154     def map_tuple(self, struct_name):
1155         return self.map_opaque_struct(struct_name, "A Tuple")
1156
1157     def map_result(self, struct_name, res_map, err_map):
1158         human_ty = struct_name.replace("LDKCResult", "Result")
1159         java_hu_struct = ""
1160         java_hu_struct += self.hu_struct_file_prefix
1161         java_hu_struct += "public class " + human_ty + " : CommonBase {\n"
1162         java_hu_struct += "\t" + human_ty + "(object _dummy, long ptr) : base(ptr) { }\n"
1163         java_hu_struct += "\t~" + human_ty + "() {\n"
1164         java_hu_struct += "\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); }\n"
1165         java_hu_struct += "\t}\n\n"
1166         java_hu_struct += "\tinternal static " + human_ty + " constr_from_ptr(long ptr) {\n"
1167         java_hu_struct += "\t\tif (bindings." + struct_name.replace("LDK", "") + "_is_ok(ptr)) {\n"
1168         java_hu_struct += "\t\t\treturn new " + human_ty + "_OK(null, ptr);\n"
1169         java_hu_struct += "\t\t} else {\n"
1170         java_hu_struct += "\t\t\treturn new " + human_ty + "_Err(null, ptr);\n"
1171         java_hu_struct += "\t\t}\n"
1172         java_hu_struct += "\t}\n"
1173
1174         java_hu_struct += "\tpublic class " + human_ty + "_OK : " + human_ty + " {\n"
1175
1176         if res_map.java_hu_ty != "void":
1177             java_hu_struct += "\t\tpublic readonly " + res_map.java_hu_ty + " res;\n"
1178         java_hu_struct += "\t\tinternal " + human_ty + "_OK(object _dummy, long ptr) : base(_dummy, ptr) {\n"
1179         if res_map.java_hu_ty == "void":
1180             pass
1181         elif res_map.to_hu_conv is not None:
1182             java_hu_struct += "\t\t\t" + res_map.java_ty + " res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1183             java_hu_struct += "\t\t\t" + res_map.to_hu_conv.replace("\n", "\n\t\t\t")
1184             java_hu_struct += "\n\t\t\tthis.res = " + res_map.to_hu_conv_name + ";\n"
1185         else:
1186             java_hu_struct += "\t\t\tthis.res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1187         java_hu_struct += "\t\t}\n"
1188         java_hu_struct += "\t}\n\n"
1189
1190         java_hu_struct += "\tpublic class " + human_ty + "_Err : " + human_ty + " {\n"
1191         if err_map.java_hu_ty != "void":
1192             java_hu_struct += "\t\tpublic readonly " + err_map.java_hu_ty + " err;\n"
1193         java_hu_struct += "\t\tinternal " + human_ty + "_Err(object _dummy, long ptr) : base(_dummy, ptr) {\n"
1194         if err_map.java_hu_ty == "void":
1195             pass
1196         elif err_map.to_hu_conv is not None:
1197             java_hu_struct += "\t\t\t" + err_map.java_ty + " err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1198             java_hu_struct += "\t\t\t" + err_map.to_hu_conv.replace("\n", "\n\t\t\t")
1199             java_hu_struct += "\n\t\t\tthis.err = " + err_map.to_hu_conv_name + ";\n"
1200         else:
1201             java_hu_struct += "\t\t\tthis.err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1202         java_hu_struct += "\t\t}\n"
1203
1204         java_hu_struct += "\t}\n\n"
1205         return java_hu_struct
1206
1207     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):
1208         out_java = ""
1209         out_c = ""
1210         out_java_struct = None
1211
1212         out_java += self.native_meth_decl(method_name, return_type_info.java_ty) + "("
1213         out_c += (return_type_info.c_ty)
1214         if return_type_info.ret_conv is not None:
1215             ret_conv_pfx, ret_conv_sfx = return_type_info.ret_conv
1216         have_args = len(argument_types) > 1 or (len(argument_types) > 0 and argument_types[0].c_ty != "void")
1217         out_c += (" " + self.c_fn_name_define_pfx(method_name, have_args))
1218
1219         for idx, arg_conv_info in enumerate(argument_types):
1220             if idx != 0:
1221                 out_java += (", ")
1222                 out_c += (", ")
1223             if arg_conv_info.c_ty != "void":
1224                 out_c += (arg_conv_info.c_ty + " " + arg_conv_info.arg_name)
1225                 out_java += (arg_conv_info.java_ty + " _" + arg_conv_info.arg_name) # Add a _ to avoid using reserved words
1226
1227         out_java_struct = ""
1228         extra_java_struct_out = ""
1229         if not args_known:
1230             out_java_struct += ("\t// Skipped " + method_name + "\n")
1231         else:
1232             if doc_comment is not None:
1233                 out_java_struct += "\t/**\n\t * " + doc_comment.replace("\n", "\n\t * ") + "\n\t */\n"
1234             hu_ret_ty = return_type_info.java_hu_ty
1235             if return_type_info.nullable:
1236                 #hu_ret_ty += "?" - apparently mono doesn't support the nullable stuff
1237                 pass
1238             if not takes_self:
1239                 if meth_n == "new":
1240                     out_java_struct += "\tpublic static " + hu_ret_ty + " of("
1241                 elif meth_n == "default":
1242                     out_java_struct += "\tpublic static " + hu_ret_ty + " with_default("
1243                 else:
1244                     out_java_struct += "\tpublic static " + hu_ret_ty + " " + meth_n + "("
1245             elif meth_n == "clone_ptr" or (struct_meth.startswith("LDKCResult") and (meth_n == "get_ok" or meth_n == "get_err")):
1246                 out_java_struct += "\tinternal " + hu_ret_ty + " " + meth_n + "("
1247             else:
1248                 if meth_n == "hash" and return_type_info.java_hu_ty == "long":
1249                     extra_java_struct_out = "\tpublic override int GetHashCode() {\n"
1250                     extra_java_struct_out += "\t\treturn (int)this.hash();\n"
1251                     extra_java_struct_out += "\t}\n"
1252                 elif meth_n == "eq" and return_type_info.java_hu_ty == "bool":
1253                     extra_java_struct_out = "\tpublic override bool Equals(object o) {\n"
1254                     extra_java_struct_out += "\t\tif (!(o is " + struct_meth + ")) return false;\n"
1255                     extra_java_struct_out += "\t\treturn this.eq((" + struct_meth + ")o);\n"
1256                     extra_java_struct_out += "\t}\n"
1257                 if meth_n == "lock":
1258                     out_java_struct += "\tpublic " + hu_ret_ty + " do_lock("
1259                 else:
1260                     out_java_struct += "\tpublic " + hu_ret_ty + " " + meth_n + "("
1261             for idx, arg in enumerate(argument_types):
1262                 if idx != 0:
1263                     if not takes_self or idx > 1:
1264                         out_java_struct += ", "
1265                 elif takes_self:
1266                     continue
1267                 if arg.java_ty != "void":
1268                     if arg.arg_name in default_constructor_args:
1269                         assert not arg.nullable
1270                         for explode_idx, explode_arg in enumerate(default_constructor_args[arg.arg_name]):
1271                             if explode_idx != 0:
1272                                 out_java_struct += (", ")
1273                             out_java_struct += (
1274                                 explode_arg.java_hu_ty + " " + arg.arg_name + "_" + explode_arg.arg_name)
1275                     else:
1276                         ty_string = arg.java_hu_ty
1277                         if arg.nullable:
1278                             #ty_string += "?" - apparently mono doesn't support the nullable stuff
1279                             pass
1280                         ty_string = self.fully_qualified_hu_ty_path(arg)
1281                         out_java_struct += ty_string + " " + arg_name_repl(arg.arg_name, arg.arg_name)
1282         out_java += (");\n")
1283         out_c += (") {\n")
1284         if out_java_struct is not None:
1285             out_java_struct += (") {\n")
1286         for info in argument_types:
1287             if info.arg_conv is not None:
1288                 out_c += ("\t" + info.arg_conv.replace('\n', "\n\t") + "\n")
1289         if return_type_info.ret_conv is not None:
1290             out_c += ("\t" + ret_conv_pfx.replace('\n', '\n\t'))
1291         elif return_type_info.c_ty != "void":
1292             out_c += ("\t" + return_type_info.c_ty + " ret_val = ")
1293         else:
1294             out_c += ("\t")
1295         if c_call_string is None:
1296             out_c += (method_name + "(")
1297         else:
1298             out_c += (c_call_string)
1299         for idx, info in enumerate(argument_types):
1300             if info.arg_conv_name is not None:
1301                 if idx != 0:
1302                     out_c += (", ")
1303                 elif c_call_string is not None:
1304                     continue
1305                 out_c += (info.arg_conv_name)
1306         out_c += (")")
1307         if return_type_info.ret_conv is not None:
1308             out_c += (ret_conv_sfx.replace('\n', '\n\t'))
1309         else:
1310             out_c += (";")
1311         for info in argument_types:
1312             if info.arg_conv_cleanup is not None:
1313                 out_c += ("\n\t" + info.arg_conv_cleanup.replace("\n", "\n\t"))
1314         if return_type_info.ret_conv is not None:
1315             out_c += ("\n\treturn " + return_type_info.ret_conv_name + ";")
1316         elif return_type_info.c_ty != "void":
1317             out_c += ("\n\treturn ret_val;")
1318         out_c += ("\n}\n\n")
1319
1320         if args_known:
1321             out_java_struct += ("\t\t")
1322             if return_type_info.java_ty != "void":
1323                 out_java_struct += (return_type_info.java_ty + " ret = ")
1324             out_java_struct += ("bindings." + method_name + "(")
1325             for idx, info in enumerate(argument_types):
1326                 if idx != 0:
1327                     out_java_struct += (", ")
1328                 if idx == 0 and takes_self:
1329                     out_java_struct += ("this.ptr")
1330                 elif info.arg_name in default_constructor_args:
1331                     out_java_struct += ("bindings." + info.java_hu_ty + "_new(")
1332                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1333                         if explode_idx != 0:
1334                             out_java_struct += (", ")
1335                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1336                         if explode_arg.from_hu_conv is not None:
1337                             out_java_struct += (
1338                                 explode_arg.from_hu_conv[0].replace(explode_arg.arg_name, expl_arg_name))
1339                         else:
1340                             out_java_struct += (expl_arg_name)
1341                     out_java_struct += (")")
1342                 elif info.from_hu_conv is not None:
1343                     out_java_struct += arg_name_repl(info.from_hu_conv[0], info.arg_name)
1344                 else:
1345                     out_java_struct += arg_name_repl(info.arg_name, info.arg_name)
1346             out_java_struct += (");\n")
1347
1348             # Like Java, the C# GC is quite aggressive and can finalize an object while a method
1349             # on it is operating. Unlike Java, this behavior appears to be better documented,
1350             # which is nice.
1351             for idx, info in enumerate(argument_types):
1352                 if idx == 0 and takes_self:
1353                     out_java_struct += ("\t\tGC.KeepAlive(this);\n")
1354                 elif info.arg_name in default_constructor_args:
1355                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1356                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1357                         out_java_struct += ("\t\tGC.KeepAlive(" + expl_arg_name + ");\n")
1358                 elif info.c_ty != "void":
1359                     out_java_struct += ("\t\tGC.KeepAlive(" + arg_name_repl(info.arg_name, info.arg_name) + ");\n")
1360
1361             if return_type_info.java_ty == "long" and return_type_info.java_hu_ty != "long":
1362                 out_java_struct += "\t\tif (ret >= 0 && ret <= 4096) { return null; }\n"
1363
1364             if return_type_info.to_hu_conv is not None:
1365                 if not takes_self:
1366                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t")
1367                         .replace("this", return_type_info.to_hu_conv_name) + "\n")
1368                 else:
1369                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t") + "\n")
1370
1371             for idx, info in enumerate(argument_types):
1372                 if idx == 0 and takes_self:
1373                     pass
1374                 elif info.arg_name in default_constructor_args:
1375                     for explode_arg in default_constructor_args[info.arg_name]:
1376                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1377                         if explode_arg.from_hu_conv is not None and return_type_info.to_hu_conv_name:
1378                             out_java_struct += ("\t\t" +
1379                                 arg_name_repl(explode_arg.from_hu_conv[1], info.arg_name)
1380                                 .replace(explode_arg.arg_name, expl_arg_name)
1381                                 .replace("this", return_type_info.to_hu_conv_name) + ";\n")
1382                 elif info.from_hu_conv is not None and info.from_hu_conv[1] != "":
1383                     if not takes_self and return_type_info.to_hu_conv_name is not None:
1384                         out_java_struct += ("\t\t" + arg_name_repl(info.from_hu_conv[1], info.arg_name)
1385                             .replace("this", return_type_info.to_hu_conv_name)
1386                             .replace("\n", "\n\t\t") + ";\n")
1387                     else:
1388                         out_java_struct += ("\t\t" + arg_name_repl(info.from_hu_conv[1], info.arg_name)
1389                             .replace("\n", "\n\t\t") + ";\n")
1390
1391             if takes_self and not takes_self_as_ref:
1392                 out_java_struct += "\t\t" + argument_types[0].from_hu_conv[1].replace("\n", "\n\t\t").replace("this_arg", "this") + ";\n"
1393             if return_type_info.to_hu_conv_name is not None:
1394                 out_java_struct += ("\t\treturn " + return_type_info.to_hu_conv_name + ";\n")
1395             elif return_type_info.java_ty != "void" and return_type_info.rust_obj != "LDK" + struct_meth:
1396                 out_java_struct += ("\t\treturn ret;\n")
1397             out_java_struct += ("\t}\n\n")
1398
1399         return (out_java, out_c, out_java_struct + extra_java_struct_out)
1400
1401     def cleanup(self):
1402         with open(self.outdir + "src/org/ldk/impl/bindings.cs", "a") as bindings:
1403             for fn_suffix in self.function_ptrs:
1404                 jret = self.function_ptrs[fn_suffix]["ret"][0]
1405                 jargs = self.function_ptrs[fn_suffix]["args"][0]
1406
1407                 bindings.write(f"""
1408         static {jret} c_callback_{fn_suffix}(int obj_ptr, int fn_id{jargs}) {{
1409                 if (obj_ptr >= js_objs.Count) {{
1410                         Console.Error.WriteLine("Got function call on unknown/free'd JS object in {fn_suffix}");
1411                         Console.Error.Flush();
1412                         Environment.Exit(42);
1413                 }}
1414                 object obj = js_objs[obj_ptr].Target;
1415                 if (obj == null) {{
1416                         Console.Error.WriteLine("Got function call on GC'd JS object in {fn_suffix}");
1417                         Console.Error.Flush();
1418                         Environment.Exit(43);
1419                 }}
1420 """)
1421                 bindings.write("\t\tswitch (fn_id) {\n")
1422                 for f in self.function_ptrs[fn_suffix]:
1423                     if f != "ret" and f != "args" and f != "call":
1424                         bindings.write(f"""\t\t\tcase {str(f)}:
1425                                 if (!(obj is {self.function_ptrs[fn_suffix][f][0]})) {{
1426                                         Console.Error.WriteLine("Got function call to object that wasn't a {self.function_ptrs[fn_suffix][f][0]} in {fn_suffix}");
1427                                         Console.Error.Flush();
1428                                         Environment.Exit(44);
1429                                 }}\n""")
1430                         call = f"(({self.function_ptrs[fn_suffix][f][0]})obj).{self.function_ptrs[fn_suffix][f][1]}({self.function_ptrs[fn_suffix][f][2]});"
1431                         if jret != "void":
1432                             bindings.write("\t\t\t\treturn " + call)
1433                         else:
1434                             bindings.write("\t\t\t\t" + call + "\n\t\t\t\treturn;")
1435                         bindings.write("\n")
1436
1437                 bindings.write(f"""\t\t\tdefault:
1438                                 Console.Error.WriteLine("Got unknown function call with id " + fn_id + " from C in {fn_suffix}");
1439                                 Console.Error.Flush();
1440                                 Environment.Exit(45);
1441                                 return{" false" if jret == "bool" else " 0" if jret != "void" else ""};
1442                 }}
1443         }}
1444         public delegate {jret} {fn_suffix}_callback(int obj_ptr, int fn_id{jargs});
1445         static {fn_suffix}_callback {fn_suffix}_callback_inst = c_callback_{fn_suffix};
1446 """)
1447                 bindings.write(self.native_meth_decl(f"register_{fn_suffix}_invoker", "int") + f"({fn_suffix}_callback callee);\n")
1448                 # Easiest way to get a static run is just define a variable, even if we dont care
1449                 bindings.write(f"\tstatic int _run_{fn_suffix}_registration = register_{fn_suffix}_invoker({fn_suffix}_callback_inst);")
1450
1451             bindings.write("""
1452 }
1453 } } }""")