_ 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 class Consts:
   9     def __init__(self, DEBUG: bool, target: Target, **kwargs):
  10         self.target = target
  11         self.c_array_class_caches = set()
  12         self.c_type_map = dict(
  13             bool = ['bool'],
  14             uint8_t = ['byte'],
  15             uint16_t = ['short'],
  16             uint32_t = ['int'],
  17             uint64_t = ['long'],
  18             int64_t = ['long'],
  19         )
  20         self.java_type_map = dict(
  21             String = "string"
  22         )
  23         self.java_hu_type_map = dict(
  24             String = "string"
  25         )
  26
  27         self.to_hu_conv_templates = dict(
  28             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}); }',
  29             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}); }'
  30         )
  31
  32         self.bindings_header = """
  33 using org.ldk.enums;
  34 using org.ldk.impl;
  35 using System;
  36 using System.Runtime.InteropServices;
  37
  38 namespace org { namespace ldk { namespace impl {
  39
  40 internal class bindings {
  41         internal class ArrayCoder : ICustomMarshaler {
  42                 int size = 0;
  43                 GCHandle pinnedArray;
  44                 public static ICustomMarshaler GetInstance(string pstrCookie) {
  45                         return new ArrayCoder();
  46                 }
  47
  48                 public Object MarshalNativeToManaged(IntPtr pNativeData) { throw new NotImplementedException(); }
  49                 public IntPtr MarshalManagedToNative(Object obj) {
  50                         if (obj.GetType() == typeof(byte[])) {
  51                                 byte[] inp = (byte[])obj;
  52                                 IntPtr data = Marshal.AllocHGlobal(inp.Length + 8);
  53                                 Marshal.WriteInt64(data, inp.Length);
  54                                 Marshal.Copy(inp, 0, data + 8, inp.Length);
  55                                 this.size = inp.Length + 8;
  56                                 return data;
  57                         } else {
  58                                 throw new NotImplementedException();
  59                         }
  60                 }
  61                 public void CleanUpNativeData(IntPtr pNativeData) {
  62                         Marshal.FreeHGlobal(pNativeData);
  63                 }
  64                 public void CleanUpManagedData(Object ManagedObj) { }
  65                 public int GetNativeDataSize() {
  66                         // Blindly guess based on the last allocation, no idea how else to implement this.
  67                         return this.size;
  68                 }
  69         }
  70
  71         /*static {
  72                 init(java.lang.Enum.class, VecOrSliceDef.class);
  73                 init_class_cache();
  74                 if (!get_lib_version_string().equals(version.get_ldk_java_bindings_version()))
  75                         throw new ArgumentException("Compiled LDK library and LDK class failes do not match");
  76                 // Fetching the LDK versions from C also checks that the header and binaries match
  77                 Console.Error.WriteLine("Loaded LDK-Java Bindings " + version.get_ldk_java_bindings_version() + " with LDK " + get_ldk_version() + " and LDK-C-Bindings " + get_ldk_c_bindings_version());
  78         }*/
  79         //static extern void init(java.lang.Class c);
  80         //static native void init_class_cache();
  81 """
  82         self.bindings_header += self.native_meth_decl("get_lib_version_string", "string") + "();\n"
  83         self.bindings_header += self.native_meth_decl("get_ldk_c_bindings_version", "string") + "();\n"
  84         self.bindings_header += self.native_meth_decl("get_ldk_version", "string") + "();\n\n"
  85
  86         self.bindings_version_file = """
  87
  88 public class version {
  89         public static string get_ldk_java_bindings_version() {
  90                 return "<git_version_ldk_garbagecollected>";
  91         }
  92 }"""
  93
  94         self.util_fn_pfx = """using org.ldk.impl;
  95 using org.ldk.enums;
  96 using org.ldk.util;
  97 using org.ldk.structs;
  98 using System;
  99
 100 namespace org { namespace ldk { namespace util {
 101 public class UtilMethods {
 102 """
 103         self.util_fn_sfx = "} } } }"
 104         self.common_base = """using System.Collections.Generic;
 105 using System.Diagnostics;
 106
 107 public class CommonBase {
 108         protected internal long ptr;
 109         protected internal LinkedList<object> ptrs_to = new LinkedList<object>();
 110         protected CommonBase(long ptr) { Trace.Assert(ptr < 0 || ptr > 4096); this.ptr = ptr; }
 111 }
 112 """
 113
 114         self.txin_defn = """public class TxIn : CommonBase {
 115         /** The witness in this input, in serialized form */
 116         public readonly byte[] witness;
 117         /** The script_sig in this input */
 118         public readonly byte[] script_sig;
 119         /** The transaction output's sequence number */
 120         public readonly int sequence;
 121         /** The txid this input is spending */
 122         public readonly byte[] previous_txid;
 123         /** The output index within the spent transaction of the output this input is spending */
 124         public readonly int previous_vout;
 125
 126         internal TxIn(object _dummy, long ptr) : base(ptr) {
 127                 this.witness = bindings.TxIn_get_witness(ptr);
 128                 this.script_sig = bindings.TxIn_get_script_sig(ptr);
 129                 this.sequence = bindings.TxIn_get_sequence(ptr);
 130                 this.previous_txid = bindings.TxIn_get_previous_txid(ptr);
 131                 this.previous_vout = bindings.TxIn_get_previous_vout(ptr);
 132         }
 133         public TxIn(byte[] witness, byte[] script_sig, int sequence, byte[] previous_txid, int previous_vout)
 134         : this(null, bindings.TxIn_new(witness, script_sig, sequence, previous_txid, previous_vout)) {}
 135
 136         ~TxIn() {
 137                 if (ptr != 0) { bindings.TxIn_free(ptr); }
 138         }
 139 }"""
 140
 141         self.txout_defn = """public class TxOut : CommonBase {
 142         /** The script_pubkey in this output */
 143         public readonly byte[] script_pubkey;
 144         /** The value, in satoshis, of this output */
 145         public readonly long value;
 146
 147     internal TxOut(object _dummy, long ptr) : base(ptr) {
 148                 this.script_pubkey = bindings.TxOut_get_script_pubkey(ptr);
 149                 this.value = bindings.TxOut_get_value(ptr);
 150         }
 151     public TxOut(long value, byte[] script_pubkey) : this(null, bindings.TxOut_new(script_pubkey, value)) {}
 152
 153         ~TxOut() {
 154                 if (ptr != 0) { bindings.TxOut_free(ptr); }
 155         }
 156 }"""
 157
 158         self.scalar_defn = """public class BigEndianScalar : CommonBase {
 159         /** The bytes of the scalar value, in big endian */
 160         public readonly byte[] scalar_bytes;
 161
 162     internal BigEndianScalar(object _dummy, long ptr) : base(ptr) {
 163                 this.scalar_bytes = bindings.BigEndianScalar_get_bytes(ptr);
 164         }
 165     public BigEndianScalar(byte[] scalar_bytes) : base(bindings.BigEndianScalar_new(scalar_bytes)) {
 166                 this.scalar_bytes = bindings.BigEndianScalar_get_bytes(ptr);
 167         }
 168
 169         ~BigEndianScalar() {
 170                 if (ptr != 0) { bindings.BigEndianScalar_free(ptr); }
 171         }
 172 }"""
 173
 174
 175         self.c_file_pfx = """
 176 // On OSX jlong (ie long long) is not equivalent to int64_t, so we override here
 177 #define int64_t jlong
 178 #include <lightning.h>
 179 #include <string.h>
 180 #include <stdatomic.h>
 181 #include <stdlib.h>
 182
 183 #define LIKELY(v) __builtin_expect(!!(v), 1)
 184 #define UNLIKELY(v) __builtin_expect(!!(v), 0)
 185
 186 """
 187
 188         self.c_file_pfx = self.c_file_pfx + "#include <stdio.h>\n#define DEBUG_PRINT(...) fprintf(stderr, __VA_ARGS__)\n"
 189
 190         if not DEBUG or sys.platform == "darwin":
 191             self.c_file_pfx = self.c_file_pfx + """#define do_MALLOC(a, _b, _c) malloc(a)
 192 #define MALLOC(a, _) malloc(a)
 193 #define FREE(p) if ((uint64_t)(p) > 4096) { free(p); }
 194 #define CHECK_ACCESS(p)
 195 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v)
 196 """
 197         if not DEBUG:
 198             self.c_file_pfx += """#define DO_ASSERT(a) (void)(a)
 199 #define CHECK(a)
 200 """
 201         if DEBUG:
 202             self.c_file_pfx = self.c_file_pfx + """#include <assert.h>
 203 // Always run a, then assert it is true:
 204 #define DO_ASSERT(a) do { bool _assert_val = (a); assert(_assert_val); } while(0)
 205 // Assert a is true or do nothing
 206 #define CHECK(a) DO_ASSERT(a)
 207
 208 void __attribute__((constructor)) debug_log_version() {
 209         if (check_get_ldk_version() == NULL)
 210                 DEBUG_PRINT("LDK version did not match the header we built against\\n");
 211         if (check_get_ldk_bindings_version() == NULL)
 212                 DEBUG_PRINT("LDK C Bindings version did not match the header we built against\\n");
 213 }
 214 """
 215
 216             if sys.platform != "darwin":
 217                 self.c_file_pfx += """
 218 // Running a leak check across all the allocations and frees of the JDK is a mess,
 219 // so instead we implement our own naive leak checker here, relying on the -wrap
 220 // linker option to wrap malloc/calloc/realloc/free, tracking everyhing allocated
 221 // and free'd in Rust or C across the generated bindings shared library.
 222 #include <threads.h>
 223 """
 224
 225                 self.c_file_pfx = self.c_file_pfx + "#include <execinfo.h>\n"
 226                 self.c_file_pfx = self.c_file_pfx + """
 227 #include <unistd.h>
 228 #include <pthread.h>
 229 static pthread_mutex_t allocation_mtx;
 230
 231 void __attribute__((constructor)) init_mtx() {
 232         DO_ASSERT(!pthread_mutex_init(&allocation_mtx, NULL));
 233 }
 234
 235 #define BT_MAX 128
 236 typedef struct allocation {
 237         struct allocation* next;
 238         void* ptr;
 239         const char* struct_name;
 240         void* bt[BT_MAX];
 241         int bt_len;
 242         unsigned long alloc_len;
 243 } allocation;
 244 static allocation* allocation_ll = NULL;
 245
 246 void* __real_malloc(size_t len);
 247 void* __real_calloc(size_t nmemb, size_t len);
 248 static void new_allocation(void* res, const char* struct_name, size_t len) {
 249         allocation* new_alloc = __real_malloc(sizeof(allocation));
 250         new_alloc->ptr = res;
 251         new_alloc->struct_name = struct_name;
 252         new_alloc->bt_len = backtrace(new_alloc->bt, BT_MAX);
 253         new_alloc->alloc_len = len;
 254         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 255         new_alloc->next = allocation_ll;
 256         allocation_ll = new_alloc;
 257         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 258 }
 259 static void* do_MALLOC(size_t len, const char* struct_name, int lineno) {
 260         void* res = __real_malloc(len);
 261         new_allocation(res, struct_name, lineno);
 262         return res;
 263 }
 264 #define MALLOC(len, struct_name) do_MALLOC(len, struct_name, __LINE__)
 265
 266 void __real_free(void* ptr);
 267 static void alloc_freed(void* ptr) {
 268         allocation* p = NULL;
 269         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 270         allocation* it = allocation_ll;
 271         while (it->ptr != ptr) {
 272                 p = it; it = it->next;
 273                 if (it == NULL) {
 274                         DEBUG_PRINT("ERROR: Tried to free unknown pointer %p at:\\n", ptr);
 275                         void* bt[BT_MAX];
 276                         int bt_len = backtrace(bt, BT_MAX);
 277                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
 278                         DEBUG_PRINT("\\n\\n");
 279                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 280                         return; // addrsan should catch malloc-unknown and print more info than we have
 281                 }
 282         }
 283         if (p) { p->next = it->next; } else { allocation_ll = it->next; }
 284         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 285         DO_ASSERT(it->ptr == ptr);
 286         __real_free(it);
 287 }
 288 static void FREE(void* ptr) {
 289         if ((uint64_t)ptr <= 4096) return; // Rust loves to create pointers to the NULL page for dummys
 290         alloc_freed(ptr);
 291         __real_free(ptr);
 292 }
 293
 294 void* __wrap_malloc(size_t len) {
 295         void* res = __real_malloc(len);
 296         new_allocation(res, "malloc call", len);
 297         return res;
 298 }
 299 void* __wrap_calloc(size_t nmemb, size_t len) {
 300         void* res = __real_calloc(nmemb, len);
 301         new_allocation(res, "calloc call", len);
 302         return res;
 303 }
 304 void __wrap_free(void* ptr) {
 305         if (ptr == NULL) return;
 306         alloc_freed(ptr);
 307         __real_free(ptr);
 308 }
 309
 310 static void CHECK_ACCESS(const void* ptr) {
 311         DO_ASSERT(!pthread_mutex_lock(&allocation_mtx));
 312         allocation* it = allocation_ll;
 313         while (it->ptr != ptr) {
 314                 it = it->next;
 315                 if (it == NULL) {
 316                         DEBUG_PRINT("ERROR: Tried to access unknown pointer %p at:\\n", ptr);
 317                         void* bt[BT_MAX];
 318                         int bt_len = backtrace(bt, BT_MAX);
 319                         backtrace_symbols_fd(bt, bt_len, STDERR_FILENO);
 320                         DEBUG_PRINT("\\n\\n");
 321                         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 322                         return; // addrsan should catch and print more info than we have
 323                 }
 324         }
 325         DO_ASSERT(!pthread_mutex_unlock(&allocation_mtx));
 326 }
 327 #define CHECK_INNER_FIELD_ACCESS_OR_NULL(v) \\
 328         if (v.is_owned && v.inner != NULL) { \\
 329                 const void *p = __unmangle_inner_ptr(v.inner); \\
 330                 if (p != NULL) { \\
 331                         CHECK_ACCESS(p); \\
 332                 } \\
 333         }
 334
 335 void* __real_realloc(void* ptr, size_t newlen);
 336 void* __wrap_realloc(void* ptr, size_t len) {
 337         if (ptr != NULL) alloc_freed(ptr);
 338         void* res = __real_realloc(ptr, len);
 339         new_allocation(res, "realloc call", len);
 340         return res;
 341 }
 342 void __wrap_reallocarray(void* ptr, size_t new_sz) {
 343         // Rust doesn't seem to use reallocarray currently
 344         DO_ASSERT(false);
 345 }
 346
 347 void __attribute__((destructor)) check_leaks() {
 348         unsigned long alloc_count = 0;
 349         unsigned long alloc_size = 0;
 350         DEBUG_PRINT("The following LDK-allocated blocks still remain.\\n");
 351         DEBUG_PRINT("Note that this is only accurate if System.gc(); System.runFinalization()\\n");
 352         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
 353         for (allocation* a = allocation_ll; a != NULL; a = a->next) {
 354                 DEBUG_PRINT("%s %p (%lu bytes) remains:\\n", a->struct_name, a->ptr, a->alloc_len);
 355                 backtrace_symbols_fd(a->bt, a->bt_len, STDERR_FILENO);
 356                 DEBUG_PRINT("\\n\\n");
 357                 alloc_count++;
 358                 alloc_size += a->alloc_len;
 359         }
 360         DEBUG_PRINT("%lu allocations remained for %lu bytes.\\n", alloc_count, alloc_size);
 361         DEBUG_PRINT("Note that this is only accurate if System.gc(); System.runFinalization()\\n");
 362         DEBUG_PRINT("was called prior to exit after all LDK objects were out of scope.\\n");
 363 }
 364 """
 365         self.c_file_pfx = self.c_file_pfx + """
 366
 367 // We assume that CVec_u8Z and u8slice are the same size and layout (and thus pointers to the two can be mixed)
 368 _Static_assert(sizeof(LDKCVec_u8Z) == sizeof(LDKu8slice), "Vec<u8> and [u8] need to have been mapped identically");
 369 _Static_assert(offsetof(LDKCVec_u8Z, data) == offsetof(LDKu8slice, data), "Vec<u8> and [u8] need to have been mapped identically");
 370 _Static_assert(offsetof(LDKCVec_u8Z, datalen) == offsetof(LDKu8slice, datalen), "Vec<u8> and [u8] need to have been mapped identically");
 371
 372 _Static_assert(sizeof(void*) <= 8, "Pointers must fit into 64 bits");
 373
 374 #define DECL_ARR_TYPE(ty, name) \\
 375         struct name##array { \\
 376                 uint64_t arr_len; /* uint32_t would suffice but we want to align uint64_ts as well */ \\
 377                 ty elems[]; \\
 378         }; \\
 379         typedef struct name##array * name##Array; \\
 380         static inline name##Array init_##name##Array(size_t arr_len, int lineno) { \\
 381                 name##Array arr = (name##Array)do_MALLOC(arr_len * sizeof(ty) + sizeof(uint64_t), #name" array init", lineno); \\
 382                 arr->arr_len = arr_len; \\
 383                 return arr; \\
 384         }
 385
 386 DECL_ARR_TYPE(int64_t, int64_t);
 387 DECL_ARR_TYPE(uint64_t, uint64_t);
 388 DECL_ARR_TYPE(int8_t, int8_t);
 389 DECL_ARR_TYPE(int16_t, int16_t);
 390 DECL_ARR_TYPE(uint32_t, uint32_t);
 391 DECL_ARR_TYPE(void*, ptr);
 392 DECL_ARR_TYPE(char, char);
 393 typedef charArray jstring;
 394
 395 static inline jstring str_ref_to_cs(const char* chars, size_t len) {
 396         charArray arr = init_charArray(len, __LINE__);
 397         memcpy(arr->elems, chars, len);
 398         return arr;
 399 }
 400 static inline LDKStr str_ref_to_owned_c(const jstring str) {
 401         char* newchars = MALLOC(str->arr_len + 1, "String chars");
 402         memcpy(newchars, str->elems, str->arr_len);
 403         newchars[str->arr_len] = 0;
 404         LDKStr res = {
 405                 .chars = newchars,
 406                 .len = str->arr_len,
 407                 .chars_is_owned = true
 408         };
 409         return res;
 410 }
 411
 412 jstring CS_LDK_get_ldk_c_bindings_version() {
 413         return str_ref_to_cs(check_get_ldk_bindings_version(), strlen(check_get_ldk_bindings_version()));
 414 }
 415 jstring CS_LDK_get_ldk_version() {
 416         return str_ref_to_cs(check_get_ldk_version(), strlen(check_get_ldk_version()));
 417 }
 418 #include "version.c"
 419 """
 420         self.c_version_file = """const char* CS_LDK_get_lib_version_string() {
 421         return "<git_version_ldk_garbagecollected>";
 422 }"""
 423
 424         self.hu_struct_file_prefix = """using org.ldk.impl;
 425 using org.ldk.enums;
 426 using org.ldk.util;
 427 using System;
 428
 429 namespace org { namespace ldk { namespace structs {
 430
 431 """
 432         self.hu_struct_file_suffix = "} } }\n"
 433         self.c_fn_args_pfx = ""
 434         self.c_fn_ty_pfx = ""
 435         self.file_ext = ".cs"
 436         self.ptr_c_ty = "int64_t"
 437         self.ptr_native_ty = "long"
 438         self.u128_native_ty = "UInt128"
 439         self.usize_c_ty = "int64_t"
 440         self.usize_native_ty = "long"
 441         self.native_zero_ptr = "0"
 442         self.result_c_ty = "jclass"
 443         self.ptr_arr = "jobjectArray"
 444         self.is_arr_some_check = ("", " != NULL")
 445         self.get_native_arr_len_call = ("(*env)->GetArrayLength(env, ", ")")
 446
 447         self.bindings_footer_wip = "\tstatic bindings() {\n"
 448     def bindings_footer(self):
 449         return self.bindings_footer_wip + "\t}\n}\n} } }\n"
 450
 451     def native_meth_decl(self, meth_name, ret_ty_str):
 452         return "\t[DllImport (\"ldkcsharp\", EntryPoint=\"CS_LDK_" + meth_name + "\")] public static extern " + ret_ty_str + " " + meth_name
 453
 454     def c_fn_name_define_pfx(self, fn_name, have_args):
 455         return " CS_LDK_" + fn_name + "("
 456
 457     def release_native_arr_ptr_call(self, ty_info, arr_var, arr_ptr_var):
 458         return None
 459     def create_native_arr_call(self, arr_len, ty_info):
 460         if ty_info.c_ty == "ptrArray":
 461             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"))
 462         return "init_" + ty_info.c_ty + "(" + arr_len + ", __LINE__)"
 463     def set_native_arr_contents(self, arr_name, arr_len, ty_info):
 464         if ty_info.c_ty == "int8_tArray":
 465             return ("memcpy(" + arr_name + "->elems, ", ", " + arr_len + ")")
 466         elif ty_info.c_ty == "int16_tArray":
 467             return ("memcpy(" + arr_name + "->elems, ", ", " + arr_len + " * 2)")
 468         else:
 469             assert False
 470     def get_native_arr_contents(self, arr_name, dest_name, arr_len, ty_info, copy):
 471         if ty_info.c_ty == "int8_tArray" or ty_info.c_ty == "int16_tArray":
 472             if copy:
 473                 byte_len = arr_len
 474                 if ty_info.c_ty == "int16_tArray":
 475                     byte_len = arr_len + " * 2"
 476                 return "memcpy(" + dest_name + ", " + arr_name + "->elems, " + byte_len + "); FREE(" + arr_name + ")"
 477         assert not copy
 478         if ty_info.c_ty == "ptrArray":
 479             return "(void*) " + arr_name + "->elems"
 480         else:
 481             return arr_name + "->elems"
 482     def get_native_arr_elem(self, arr_name, idxc, ty_info):
 483         assert False # Only called if above is None
 484     def get_native_arr_ptr_call(self, ty_info):
 485         if ty_info.subty is not None:
 486             return "(" + ty_info.subty.c_ty + "*)(((uint8_t*)", ") + 8)"
 487         return "(" + ty_info.c_ty + "*)(((uint8_t*)", ") + 8)"
 488     def get_native_arr_entry_call(self, ty_info, arr_name, idxc, entry_access):
 489         return None
 490     def cleanup_native_arr_ref_contents(self, arr_name, dest_name, arr_len, ty_info):
 491         if ty_info.c_ty == "int8_tArray":
 492             return "FREE(" + arr_name + ");"
 493         else:
 494             return "FREE(" + arr_name + ")"
 495
 496     def map_hu_array_elems(self, arr_name, conv_name, arr_ty, elem_ty):
 497         if elem_ty.java_hu_ty == "UInt5":
 498             return arr_name + " != null ? InternalUtils.convUInt5Array(" + arr_name + ") : null"
 499         elif elem_ty.java_hu_ty == "WitnessVersion":
 500             return arr_name + " != null ? InternalUtils.convWitnessVersionArray(" + arr_name + ") : null"
 501         else:
 502             return arr_name + " != null ? InternalUtils.mapArray(" + arr_name + ", " + conv_name + " => " + elem_ty.from_hu_conv[0] + ") : null"
 503
 504     def str_ref_to_native_call(self, var_name, str_len):
 505         return "str_ref_to_cs(" + var_name + ", " + str_len + ")"
 506     def str_ref_to_c_call(self, var_name):
 507         return "str_ref_to_owned_c(" + var_name + ")"
 508     def str_to_hu_conv(self, var_name):
 509         return None
 510     def str_from_hu_conv(self, var_name):
 511         return None
 512
 513     def init_str(self):
 514         return ""
 515
 516     def var_decl_statement(self, ty_string, var_name, statement):
 517         return ty_string + " " + var_name + " = " + statement
 518
 519     def get_java_arr_len(self, arr_name):
 520         return arr_name + ".Length"
 521     def get_java_arr_elem(self, elem_ty, arr_name, idx):
 522         return arr_name + "[" + idx + "]"
 523     def constr_hu_array(self, ty_info, arr_len):
 524         base_ty = ty_info.subty.java_hu_ty.split("[")[0].split("<")[0]
 525         conv = "new " + base_ty + "[" + arr_len + "]"
 526         if "[" in ty_info.subty.java_hu_ty.split("<")[0]:
 527             # Do a bit of a dance to move any excess [] to the end
 528             conv += "[" + ty_info.subty.java_hu_ty.split("<")[0].split("[")[1]
 529         return conv
 530     def cleanup_converted_native_array(self, ty_info, arr_name):
 531         return None
 532
 533     def primitive_arr_from_hu(self, arr_ty, fixed_len, arr_name):
 534         mapped_ty = arr_ty.subty
 535         if arr_ty.rust_obj == "LDKU128":
 536             return ("" + arr_name + ".getLEBytes()", "")
 537         if fixed_len is not None:
 538             return ("InternalUtils.check_arr_len(" + arr_name + ", " + fixed_len + ")", "")
 539         return None
 540     def primitive_arr_to_hu(self, arr_ty, fixed_len, arr_name, conv_name):
 541         if arr_ty.rust_obj == "LDKU128":
 542             return "org.ldk.util.UInt128 " + conv_name + " = new org.ldk.util.UInt128(" + arr_name + ");"
 543         return None
 544
 545     def java_arr_ty_str(self, elem_ty_str):
 546         return elem_ty_str + "[]"
 547
 548     def for_n_in_range(self, n, minimum, maximum):
 549         return "for (int " + n + " = " + minimum + "; " + n + " < " + maximum + "; " + n + "++) {"
 550     def for_n_in_arr(self, n, arr_name, arr_elem_ty):
 551         return ("foreach (" + arr_elem_ty.java_hu_ty + " " + n + " in " + arr_name + ") { ", " }")
 552
 553     def get_ptr(self, var):
 554         return var + ".ptr"
 555     def set_null_skip_free(self, var):
 556         return var + ".ptr" + " = 0;"
 557
 558     def add_ref(self, holder, referent):
 559         return "if (" + holder + " != null) { " + holder + ".ptrs_to.AddLast(" + referent + "); }"
 560
 561     def fully_qualified_hu_ty_path(self, ty):
 562         if ty.java_fn_ty_arg.startswith("L") and ty.java_fn_ty_arg.endswith(";"):
 563             return ty.java_hu_ty
 564         if ty.java_hu_ty == "UnqualifiedError" or ty.java_hu_ty == "UInt128" or ty.java_hu_ty == "UInt5" or ty.java_hu_ty == "WitnessVersion":
 565             return "org.ldk.util." + ty.java_hu_ty
 566         if not ty.is_native_primitive and ty.rust_obj is not None and not "[]" in ty.java_hu_ty:
 567             return "org.ldk.structs." + ty.java_hu_ty
 568         return ty.java_hu_ty
 569
 570     def native_c_unitary_enum_map(self, struct_name, variants, enum_doc_comment):
 571         out_java_enum = "namespace org { namespace ldk { namespace enums {"
 572         out_java = ""
 573         out_c = ""
 574
 575         out_c = "static inline LDK" + struct_name + " LDK" + struct_name + "_from_cs(int32_t ord) {\n"
 576         out_c += "\tswitch (ord) {\n"
 577
 578         if enum_doc_comment is not None:
 579             out_java_enum += "/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
 580         out_java_enum += "public enum " + struct_name + " {\n"
 581         ord_v = 0
 582         for var, var_docs in variants:
 583             if var_docs is not None:
 584                 out_java_enum += "\t/**\n\t * " + var_docs.replace("\n", "\n\t * ") + "\n\t */\n"
 585             out_java_enum += "\t" + var + ",\n"
 586             out_c = out_c + "\t\tcase %d: return %s;\n" % (ord_v, var)
 587             ord_v = ord_v + 1
 588         out_java_enum += "}"
 589         out_c += "\t\tdefault: abort();\n"
 590         out_c += "\t}\n"
 591         out_c += "}\n"
 592
 593         out_c = out_c + "static inline int32_t LDK" + struct_name + "_to_cs(LDK" + struct_name + " val) {\n"
 594         out_c = out_c + "\tswitch (val) {\n"
 595         ord_v = 0
 596         for var, _ in variants:
 597             out_c = out_c + "\t\tcase " + var + ": return %d;\n" % ord_v
 598             ord_v = ord_v + 1
 599         out_c = out_c + "\t\tdefault: abort();\n"
 600         out_c = out_c + "\t}\n"
 601         out_c = out_c + "}\n"
 602
 603         return (out_c, out_java_enum + "} } }\n", out_java)
 604
 605     def c_unitary_enum_to_native_call(self, ty_info):
 606         return (ty_info.rust_obj + "_to_cs(", ")")
 607     def native_unitary_enum_to_c_call(self, ty_info):
 608         return (ty_info.rust_obj + "_from_cs(", ")")
 609
 610     def c_complex_enum_pfx(self, struct_name, variants, init_meth_jty_strs):
 611         out_c = ""
 612         for var in variants:
 613             out_c = out_c + "static jclass " + struct_name + "_" + var + "_class = NULL;\n"
 614             out_c = out_c + "static jmethodID " + struct_name + "_" + var + "_meth = NULL;\n"
 615         out_c += "void" + self.c_fn_name_define_pfx(struct_name.replace("_", "_1") + "_init", True) + self.c_fn_args_pfx + ") {\n"
 616         for var_name in variants:
 617             out_c += "\t" + struct_name + "_" + var_name + "_class =\n"
 618             out_c += "\t\t(*env)->NewGlobalRef(env, (*env)->FindClass(env, \"org/ldk/impl/bindings$" + struct_name + "$" + var_name + "\"));\n"
 619             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_class != NULL);\n"
 620             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"
 621             out_c += "\tCHECK(" + struct_name + "_" + var_name + "_meth != NULL);\n"
 622         out_c = out_c + "}\n"
 623         return out_c
 624
 625     def c_complex_enum_pass_ty(self, struct_name):
 626         return "jobject"
 627
 628     def c_constr_native_complex_enum(self, struct_name, variant, c_params):
 629         ret = "(*env)->NewObject(env, " + struct_name + "_" + variant + "_class, " + struct_name + "_" + variant + "_meth"
 630         for param in c_params:
 631             ret = ret + ", " + param
 632         return ret + ")"
 633
 634     def native_c_map_trait(self, struct_name, field_vars, flattened_field_vars, field_fns, trait_doc_comment):
 635         out_java_trait = ""
 636         out_java = ""
 637
 638         # First generate most of the Java code, note that we need information about java method argument strings for C
 639         out_java_trait += self.hu_struct_file_prefix
 640         if trait_doc_comment is not None:
 641             out_java_trait += "/**\n * " + trait_doc_comment.replace("\n", "\n * ") + "\n */\n"
 642         out_java_trait = out_java_trait + "public class " + struct_name.replace("LDK","") + " : CommonBase {\n"
 643         out_java_trait = out_java_trait + "\tinternal readonly bindings." + struct_name + " bindings_instance;\n"
 644         out_java_trait = out_java_trait + "\tinternal " + struct_name.replace("LDK", "") + "(object _dummy, long ptr) : base(ptr) { bindings_instance = null; }\n"
 645         out_java_trait = out_java_trait + "\tprivate " + struct_name.replace("LDK", "") + "(bindings." + struct_name + " arg"
 646         for var in flattened_field_vars:
 647             if isinstance(var, ConvInfo):
 648                 out_java_trait += ", " + var.java_hu_ty + " " + var.arg_name
 649             else:
 650                 out_java_trait += ", bindings." + var[0] + " " + var[1]
 651         out_java_trait += ") : base(bindings." + struct_name + "_new(arg"
 652         for var in flattened_field_vars:
 653             if isinstance(var, ConvInfo):
 654                 if var.from_hu_conv is not None:
 655                     out_java_trait = out_java_trait + ", " + var.from_hu_conv[0]
 656                 else:
 657                     out_java_trait = out_java_trait + ", " + var.arg_name
 658             else:
 659                 out_java_trait = out_java_trait + ", " + var[1]
 660         out_java_trait = out_java_trait + ")) {\n"
 661         out_java_trait = out_java_trait + "\t\tthis.ptrs_to.AddLast(arg);\n"
 662         for var in flattened_field_vars:
 663             if isinstance(var, ConvInfo):
 664                 if var.from_hu_conv is not None and var.from_hu_conv[1] != "":
 665                     out_java_trait = out_java_trait + "\t\t" + var.from_hu_conv[1].replace("\n", "\n\t\t") + ";\n"
 666             else:
 667                 out_java_trait = out_java_trait + "\t\tthis.ptrs_to.AddLast(" + var[1] + ");\n"
 668         out_java_trait = out_java_trait + "\t\tthis.bindings_instance = arg;\n"
 669         out_java_trait = out_java_trait + "\t}\n"
 670         out_java_trait = out_java_trait + "\t~" + struct_name.replace("LDK","") + "() {\n"
 671         out_java_trait = out_java_trait + "\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); }\n"
 672         out_java_trait = out_java_trait + "\t}\n\n"
 673
 674         java_trait_wrapper = "\tprivate class " + struct_name + "Holder { internal " + struct_name.replace("LDK", "") + " held; }\n"
 675         java_trait_wrapper += "\tprivate class " + struct_name + "Impl : bindings." + struct_name + " {\n"
 676         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"
 677         java_trait_wrapper += "\t\tprivate " + struct_name.replace("LDK", "") + "Interface arg;\n"
 678         java_trait_wrapper += "\t\tprivate " + struct_name + "Holder impl_holder;\n"
 679         java_trait_constr = "\tpublic static " + struct_name.replace("LDK", "") + " new_impl(" + struct_name.replace("LDK", "") + "Interface arg"
 680         for var in flattened_field_vars:
 681             if isinstance(var, ConvInfo):
 682                 java_trait_constr += ", " + var.java_hu_ty + " " + var.arg_name
 683             else:
 684                 # Ideally we'd be able to take any instance of the interface, but our C code can only represent
 685                 # Java-implemented version, so we require users pass a Java implementation here :/
 686                 java_trait_constr += ", " + var[0].replace("LDK", "") + "." + var[0].replace("LDK", "") + "Interface " + var[1] + "_impl"
 687         java_trait_constr = java_trait_constr + ") {\n\t\t" + struct_name + "Holder impl_holder = new " + struct_name + "Holder();\n"
 688         java_trait_constr = java_trait_constr + "\t\timpl_holder.held = new " + struct_name.replace("LDK", "") + "(new " + struct_name + "Impl(arg, impl_holder)"
 689         out_java_trait += "\tpublic interface " + struct_name.replace("LDK", "") + "Interface {\n"
 690         out_java += "\tpublic interface " + struct_name + " {\n"
 691         java_meths = []
 692         for fn_line in field_fns:
 693             java_meth_descr = "("
 694             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 695                 fn_name = fn_line.fn_name
 696                 if fn_name == "lock": # reserved symbol
 697                     fn_name = "do_lock"
 698                 out_java += "\t\t" + fn_line.ret_ty_info.java_ty + " " + fn_name + "("
 699                 java_trait_wrapper += "\t\tpublic " + fn_line.ret_ty_info.java_ty + " " + fn_name + "("
 700                 out_java_trait += "\t\t/**\n\t\t * " + fn_line.docs.replace("\n", "\n\t\t * ") + "\n\t\t */\n"
 701                 out_java_trait += "\t\t" + fn_line.ret_ty_info.java_hu_ty + " " + fn_name + "("
 702
 703                 for idx, arg_conv_info in enumerate(fn_line.args_ty):
 704                     if idx >= 1:
 705                         out_java += ", "
 706                         java_trait_wrapper += ", "
 707                         out_java_trait += ", "
 708                     out_java += arg_conv_info.java_ty + " _" + arg_conv_info.arg_name
 709                     out_java_trait += arg_conv_info.java_hu_ty + " _" + arg_conv_info.arg_name
 710                     java_trait_wrapper += arg_conv_info.java_ty + " _" + arg_conv_info.arg_name
 711                     java_meth_descr = java_meth_descr + arg_conv_info.java_fn_ty_arg
 712                 java_meth_descr = java_meth_descr + ")" + fn_line.ret_ty_info.java_fn_ty_arg
 713                 java_meths.append((fn_line.fn_name, java_meth_descr))
 714
 715                 out_java += ");\n"
 716                 out_java_trait += ");\n"
 717                 java_trait_wrapper += ") {\n"
 718
 719                 for arg_info in fn_line.args_ty:
 720                     if arg_info.to_hu_conv is not None:
 721                         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"
 722
 723                 if fn_line.ret_ty_info.java_ty != "void":
 724                     java_trait_wrapper += "\t\t\t" + fn_line.ret_ty_info.java_hu_ty + " ret = arg." + fn_name + "("
 725                 else:
 726                     java_trait_wrapper += "\t\t\targ." + fn_name + "("
 727
 728                 for idx, arg_info in enumerate(fn_line.args_ty):
 729                     if idx != 0:
 730                         java_trait_wrapper += ", "
 731                     if arg_info.to_hu_conv_name is not None:
 732                         java_trait_wrapper += arg_info.to_hu_conv_name.replace(arg_info.arg_name, "_" + arg_info.arg_name)
 733                     else:
 734                         java_trait_wrapper += "_" + arg_info.arg_name
 735
 736                 java_trait_wrapper += ");\n"
 737                 java_trait_wrapper += "\t\t\t\tGC.KeepAlive(arg);\n"
 738                 if fn_line.ret_ty_info.java_ty != "void":
 739                     if fn_line.ret_ty_info.from_hu_conv is not None:
 740                         java_trait_wrapper += "\t\t\t" + fn_line.ret_ty_info.java_ty + " result = " + fn_line.ret_ty_info.from_hu_conv[0] + ";\n"
 741                         if fn_line.ret_ty_info.from_hu_conv[1] != "":
 742                             java_trait_wrapper += "\t\t\t" + fn_line.ret_ty_info.from_hu_conv[1].replace("this", "impl_holder.held") + ";\n"
 743                         java_trait_wrapper += "\t\t\treturn result;\n"
 744                     else:
 745                         java_trait_wrapper += "\t\t\treturn ret;\n"
 746                 java_trait_wrapper += "\t\t}\n"
 747         java_trait_wrapper += "\t}"
 748         for var in field_vars:
 749             if isinstance(var, ConvInfo):
 750                 java_trait_constr = java_trait_constr + ", " + var.arg_name
 751             else:
 752                 java_trait_constr += ", " + var[1] + ".new_impl(" + var[1] + "_impl"
 753                 suptrait_constr = ""
 754                 for suparg in var[2]:
 755                     if isinstance(suparg, ConvInfo):
 756                         suptrait_constr += ", " + suparg.arg_name
 757                     else:
 758                         suptrait_constr += ", " + suparg[1] + "_impl"
 759                 java_trait_constr += suptrait_constr + ").bindings_instance"
 760                 for suparg in var[2]:
 761                     if isinstance(suparg, ConvInfo):
 762                         java_trait_constr += ", " + suparg.arg_name
 763                     else:
 764                         java_trait_constr += ", " + suparg[1] + ".new_impl("
 765                         # Blindly assume that we can just strip the first arg to build the args for the supertrait
 766                         java_trait_constr += suptrait_constr.split(", ", 1)[1]
 767                         java_trait_constr += ").bindings_instance"
 768         out_java_trait += "\t}\n" + java_trait_wrapper + "\n"
 769         out_java_trait += java_trait_constr + ");\n\t\treturn impl_holder.held;\n\t}\n"
 770
 771         out_java += "\t}\n"
 772
 773         out_java += self.native_meth_decl(struct_name + "_new", "long") + "(" + struct_name + " impl"
 774         for var in flattened_field_vars:
 775             if isinstance(var, ConvInfo):
 776                 out_java += ", " + var.java_ty + " " + var.arg_name
 777             else:
 778                 out_java += ", " + var[0] + " " + var[1]
 779         out_java += ");\n"
 780
 781         # Now that we've written out our java code (and created java_meths), generate C
 782         out_c = "typedef struct " + struct_name + "_JCalls {\n"
 783         out_c = out_c + "\tatomic_size_t refcnt;\n"
 784         out_c = out_c + "\tJavaVM *vm;\n"
 785         out_c = out_c + "\tjweak o;\n"
 786         for var in flattened_field_vars:
 787             if isinstance(var, ConvInfo):
 788                 # We're a regular ol' field
 789                 pass
 790             else:
 791                 # We're a supertrait
 792                 out_c = out_c + "\t" + var[0] + "_JCalls* " + var[1] + ";\n"
 793         for fn in field_fns:
 794             if fn.fn_name != "free" and fn.fn_name != "cloned":
 795                 out_c = out_c + "\tjmethodID " + fn.fn_name + "_meth;\n"
 796         out_c = out_c + "} " + struct_name + "_JCalls;\n"
 797
 798         for fn_line in field_fns:
 799             if fn_line.fn_name == "free":
 800                 out_c = out_c + "static void " + struct_name + "_JCalls_free(void* this_arg) {\n"
 801                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
 802                 out_c = out_c + "\tif (atomic_fetch_sub_explicit(&j_calls->refcnt, 1, memory_order_acquire) == 1) {\n"
 803                 out_c = out_c + "\t\t(*env)->DeleteWeakGlobalRef(env, j_calls->o);\n"
 804                 out_c = out_c + "\t\tFREE(j_calls);\n"
 805                 out_c = out_c + "\t}\n}\n"
 806
 807         for idx, fn_line in enumerate(field_fns):
 808             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 809                 assert fn_line.ret_ty_info.ty_info.get_full_rust_ty()[1] == ""
 810                 out_c = out_c + fn_line.ret_ty_info.ty_info.get_full_rust_ty()[0] + " " + fn_line.fn_name + "_" + struct_name + "_jcall("
 811                 if fn_line.self_is_const:
 812                     out_c = out_c + "const void* this_arg"
 813                 else:
 814                     out_c = out_c + "void* this_arg"
 815
 816                 for idx, arg in enumerate(fn_line.args_ty):
 817                     out_c = out_c + ", " + arg.ty_info.get_full_rust_ty()[0] + " " + arg.arg_name + arg.ty_info.get_full_rust_ty()[1]
 818
 819                 out_c = out_c + ") {\n"
 820                 out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n"
 821
 822                 for arg_info in fn_line.args_ty:
 823                     if arg_info.ret_conv is not None:
 824                         out_c = out_c + "\t" + arg_info.ret_conv[0].replace('\n', '\n\t')
 825                         out_c = out_c + arg_info.arg_name
 826                         out_c = out_c + arg_info.ret_conv[1].replace('\n', '\n\t') + "\n"
 827
 828                 out_c = out_c + "\tjobject obj = (*env)->NewLocalRef(env, j_calls->o);\n\tCHECK(obj != NULL);\n"
 829                 if fn_line.ret_ty_info.c_ty.endswith("Array"):
 830                     out_c = out_c + "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->CallObjectMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 831                 elif fn_line.ret_ty_info.c_ty == "void":
 832                     out_c += "\t(*env)->CallVoidMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 833                 elif fn_line.ret_ty_info.java_hu_ty == "string" or "org/ldk/enums" in fn_line.ret_ty_info.java_fn_ty_arg:
 834                     # Manually write out string methods as they're just an Object
 835                     out_c += "\t" + fn_line.ret_ty_info.c_ty + " ret = (*env)->CallObjectMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 836                 elif not fn_line.ret_ty_info.passed_as_ptr:
 837                     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"
 838                 else:
 839                     out_c = out_c + "\tuint64_t ret = (*env)->CallLongMethod(env, obj, j_calls->" + fn_line.fn_name + "_meth"
 840
 841                 for idx, arg_info in enumerate(fn_line.args_ty):
 842                     if arg_info.ret_conv is not None:
 843                         out_c = out_c + ", " + arg_info.ret_conv_name
 844                     else:
 845                         out_c = out_c + ", " + arg_info.arg_name
 846                 out_c = out_c + ");\n"
 847
 848                 out_c += "\tif (UNLIKELY((*env)->ExceptionCheck(env))) {\n"
 849                 out_c += "\t\t(*env)->ExceptionDescribe(env);\n"
 850                 out_c += "\t\t(*env)->FatalError(env, \"A call to " + fn_line.fn_name + " in " + struct_name + " from rust threw an exception.\");\n"
 851                 out_c += "\t}\n"
 852
 853                 if fn_line.ret_ty_info.arg_conv is not None:
 854                     out_c += "\t" + fn_line.ret_ty_info.arg_conv.replace("\n", "\n\t") + "\n"
 855                     out_c += "\treturn " + fn_line.ret_ty_info.arg_conv_name + ";\n"
 856                 else:
 857                     if not fn_line.ret_ty_info.passed_as_ptr and fn_line.ret_ty_info.c_ty != "void":
 858                         out_c += "\treturn ret;\n"
 859
 860                 out_c = out_c + "}\n"
 861
 862         # If we can, write out a clone function whether we need one or not, as we use them in moving to rust
 863         can_clone_with_ptr = True
 864         for var in field_vars:
 865             if isinstance(var, ConvInfo):
 866                 can_clone_with_ptr = False
 867         if can_clone_with_ptr:
 868             out_c = out_c + "static void " + struct_name + "_JCalls_cloned(" + struct_name + "* new_obj) {\n"
 869             out_c = out_c + "\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) new_obj->this_arg;\n"
 870             out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->refcnt, 1, memory_order_release);\n"
 871             for var in field_vars:
 872                 if not isinstance(var, ConvInfo):
 873                     out_c = out_c + "\tatomic_fetch_add_explicit(&j_calls->" + var[1] + "->refcnt, 1, memory_order_release);\n"
 874             out_c = out_c + "}\n"
 875
 876         out_c = out_c + "static inline " + struct_name + " " + struct_name + "_init (" + self.c_fn_args_pfx + ", jobject o"
 877         for var in flattened_field_vars:
 878             if isinstance(var, ConvInfo):
 879                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
 880             else:
 881                 out_c = out_c + ", jobject " + var[1]
 882         out_c = out_c + ") {\n"
 883
 884         out_c = out_c + "\tjclass c = (*env)->GetObjectClass(env, o);\n"
 885         out_c = out_c + "\tCHECK(c != NULL);\n"
 886         out_c = out_c + "\t" + struct_name + "_JCalls *calls = MALLOC(sizeof(" + struct_name + "_JCalls), \"" + struct_name + "_JCalls\");\n"
 887         out_c = out_c + "\tatomic_init(&calls->refcnt, 1);\n"
 888         out_c = out_c + "\tDO_ASSERT((*env)->GetJavaVM(env, &calls->vm) == 0);\n"
 889         out_c = out_c + "\tcalls->o = (*env)->NewWeakGlobalRef(env, o);\n"
 890
 891         for (fn_name, java_meth_descr) in java_meths:
 892             if fn_name != "free" and fn_name != "cloned":
 893                 out_c = out_c + "\tcalls->" + fn_name + "_meth = (*env)->GetMethodID(env, c, \"" + fn_name + "\", \"" + java_meth_descr + "\");\n"
 894                 out_c = out_c + "\tCHECK(calls->" + fn_name + "_meth != NULL);\n"
 895
 896         for var in flattened_field_vars:
 897             if isinstance(var, ConvInfo) and var.arg_conv is not None:
 898                 out_c = out_c + "\n\t" + var.arg_conv.replace("\n", "\n\t") +"\n"
 899         out_c = out_c + "\n\t" + struct_name + " ret = {\n"
 900         out_c = out_c + "\t\t.this_arg = (void*) calls,\n"
 901         for fn_line in field_fns:
 902             if fn_line.fn_name != "free" and fn_line.fn_name != "cloned":
 903                 out_c = out_c + "\t\t." + fn_line.fn_name + " = " + fn_line.fn_name + "_" + struct_name + "_jcall,\n"
 904             elif fn_line.fn_name == "free":
 905                 out_c = out_c + "\t\t.free = " + struct_name + "_JCalls_free,\n"
 906             else:
 907                 out_c = out_c + "\t\t.cloned = " + struct_name + "_JCalls_cloned,\n"
 908         for var in field_vars:
 909             if isinstance(var, ConvInfo):
 910                 if var.arg_conv_name is not None:
 911                     out_c = out_c + "\t\t." + var.arg_name + " = " + var.arg_conv_name + ",\n"
 912                     out_c = out_c + "\t\t.set_" + var.arg_name + " = NULL,\n"
 913                 else:
 914                     out_c = out_c + "\t\t." + var.var_name + " = " + var.var_name + ",\n"
 915                     out_c = out_c + "\t\t.set_" + var.var_name + " = NULL,\n"
 916             else:
 917                 out_c += "\t\t." + var[1] + " = " + var[0] + "_init(env, clz, " + var[1]
 918                 for suparg in var[2]:
 919                     if isinstance(suparg, ConvInfo):
 920                         out_c = out_c + ", " + suparg.arg_name
 921                     else:
 922                         out_c = out_c + ", " + suparg[1]
 923                 out_c += "),\n"
 924         out_c = out_c + "\t};\n"
 925         for var in flattened_field_vars:
 926             if not isinstance(var, ConvInfo):
 927                 out_c = out_c + "\tcalls->" + var[1] + " = ret." + var[1] + ".this_arg;\n"
 928         out_c = out_c + "\treturn ret;\n"
 929         out_c = out_c + "}\n"
 930
 931         out_c += "int64_t " + self.c_fn_name_define_pfx(struct_name + "_new", True) + "jobject o"
 932         for var in flattened_field_vars:
 933             if isinstance(var, ConvInfo):
 934                 out_c = out_c + ", " + var.c_ty + " " + var.arg_name
 935             else:
 936                 out_c = out_c + ", jobject " + var[1]
 937         out_c = out_c + ") {\n"
 938         out_c = out_c + "\t" + struct_name + " *res_ptr = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n"
 939         out_c = out_c + "\t*res_ptr = " + struct_name + "_init(env, clz, o"
 940         for var in flattened_field_vars:
 941             if isinstance(var, ConvInfo):
 942                 out_c = out_c + ", " + var.arg_name
 943             else:
 944                 out_c = out_c + ", " + var[1]
 945         out_c = out_c + ");\n"
 946         out_c = out_c + "\treturn tag_ptr(res_ptr, true);\n"
 947         out_c = out_c + "}\n"
 948
 949         for var in flattened_field_vars:
 950             if not isinstance(var, ConvInfo):
 951                 out_java_trait += "\n\t/**\n"
 952                 out_java_trait += "\t * Gets the underlying " + var[1] + ".\n"
 953                 out_java_trait += "\t */\n"
 954                 underscore_name = ''.join('_' + c.lower() if c.isupper() else c for c in var[1]).strip('_')
 955                 out_java_trait += "\tpublic " + var[1] + " get_" + underscore_name + "() {\n"
 956                 out_java_trait += "\t\t" + var[1] + " res = new " + var[1] + "(null, bindings." + struct_name + "_get_" + var[1] + "(this.ptr));\n"
 957                 out_java_trait += "\t\tthis.ptrs_to.AddLast(res);\n"
 958                 out_java_trait += "\t\treturn res;\n"
 959                 out_java_trait += "\t}\n"
 960                 out_java_trait += "\n"
 961
 962                 out_java += self.native_meth_decl(struct_name + "_get_" + var[1], "long") + "(long arg);\n"
 963
 964                 out_c += "int64_t " + self.c_fn_name_define_pfx(struct_name + "_get_" + var[1], True) + "int64_t arg) {\n"
 965                 out_c += "\t" + struct_name + " *inp = (" + struct_name + " *)untag_ptr(arg);\n"
 966                 out_c += "\treturn tag_ptr(&inp->" + var[1] + ", false);\n"
 967                 out_c += "}\n"
 968
 969         return (out_java, out_java_trait, out_c)
 970
 971     def trait_struct_inc_refcnt(self, ty_info):
 972         base_conv = "\nif (" + ty_info.var_name + "_conv.free == " + ty_info.rust_obj + "_JCalls_free) {\n"
 973         base_conv = base_conv + "\t// If this_arg is a JCalls struct, then we need to increment the refcnt in it.\n"
 974         base_conv = base_conv + "\t" + ty_info.rust_obj + "_JCalls_cloned(&" + ty_info.var_name + "_conv);\n}"
 975         return base_conv
 976
 977     def map_complex_enum(self, struct_name, variant_list, camel_to_snake, enum_doc_comment):
 978         bindings_type = struct_name.replace("LDK", "")
 979         java_hu_type = struct_name.replace("LDK", "").replace("COption", "Option")
 980
 981         out_java_enum = ""
 982         out_java = ""
 983         out_c = ""
 984
 985         out_java_enum += (self.hu_struct_file_prefix)
 986
 987         java_hu_class = "/**\n * " + enum_doc_comment.replace("\n", "\n * ") + "\n */\n"
 988         java_hu_class += "public class " + java_hu_type + " : CommonBase {\n"
 989         java_hu_class += f"\tprotected {java_hu_type}(object _dummy, long ptr) : base(ptr)" + " { }\n"
 990         java_hu_class += "\t~" + java_hu_type + "() {\n"
 991         java_hu_class += "\t\tif (ptr != 0) { bindings." + bindings_type + "_free(ptr); }\n"
 992         java_hu_class += "\t}\n\n"
 993         java_hu_class += f"\tinternal static {java_hu_type} constr_from_ptr(long ptr) {{\n"
 994         java_hu_class += f"\t\tlong raw_ty = bindings." + struct_name + "_ty_from_ptr(ptr);\n"
 995         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"
 996         out_c += "\t" + struct_name + " *obj = (" + struct_name + "*)untag_ptr(ptr);\n"
 997         out_c += "\tswitch(obj->tag) {\n"
 998         java_hu_class += "\t\tswitch (raw_ty) {\n"
 999         java_hu_subclasses = ""
1000
1001         var_idx = 0
1002         for var in variant_list:
1003             java_hu_subclasses += "\t/** A " + java_hu_type + " of type " + var.var_name + " */\n"
1004             java_hu_subclasses += "\tpublic class " + java_hu_type + "_" + var.var_name + " : " + java_hu_type + " {\n"
1005             java_hu_class += f"\t\t\tcase {var_idx}: "
1006             java_hu_class += "return new " + java_hu_type + "_" + var.var_name + "(ptr);\n"
1007             out_c += f"\t\tcase {struct_name}_{var.var_name}: return {var_idx};\n"
1008             hu_conv_body = ""
1009             for idx, (field_ty, field_docs) in enumerate(var.fields):
1010                 if field_docs is not None:
1011                     java_hu_subclasses += "\t\t/**\n\t\t * " + field_docs.replace("\n", "\n\t\t * ") + "\n\t\t */\n"
1012                 java_hu_subclasses += f"\t\tpublic {field_ty.java_hu_ty} {field_ty.arg_name};\n"
1013                 if field_ty.to_hu_conv is not None:
1014                     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"
1015                     hu_conv_body += f"\t\t\t" + field_ty.to_hu_conv.replace("\n", "\n\t\t\t") + "\n"
1016                     hu_conv_body += f"\t\t\tthis." + field_ty.arg_name + " = " + field_ty.to_hu_conv_name + ";\n"
1017                 else:
1018                     hu_conv_body += f"\t\t\tthis.{field_ty.arg_name} = bindings.{struct_name}_{var.var_name}_get_{field_ty.arg_name}(ptr);\n"
1019             java_hu_subclasses += "\t\tinternal " + java_hu_type + "_" + var.var_name + "(long ptr) : base(null, ptr) {\n"
1020             java_hu_subclasses += hu_conv_body
1021             java_hu_subclasses += "\t\t}\n\t}\n"
1022             var_idx += 1
1023         java_hu_class += "\t\t\tdefault:\n\t\t\t\tthrow new ArgumentException(\"Impossible enum variant\");\n\t\t}\n\t}\n\n"
1024         out_java += self.native_meth_decl(struct_name + "_ty_from_ptr", "long") + "(long ptr);\n"
1025         out_c += ("\t\tdefault: abort();\n")
1026         out_c += ("\t}\n}\n")
1027
1028         for var in variant_list:
1029             for idx, (field_map, _) in enumerate(var.fields):
1030                 fn_name = f"{struct_name}_{var.var_name}_get_{field_map.arg_name}"
1031                 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"
1032                 out_c += "\t" + struct_name + " *obj = (" + struct_name + "*)untag_ptr(ptr);\n"
1033                 out_c += f"\tassert(obj->tag == {struct_name}_{var.var_name});\n"
1034                 if field_map.ret_conv is not None:
1035                     out_c += ("\t\t\t" + field_map.ret_conv[0].replace("\n", "\n\t\t\t"))
1036                     if var.tuple_variant:
1037                         out_c += "obj->" + camel_to_snake(var.var_name)
1038                     else:
1039                         out_c += "obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name
1040                     out_c += (field_map.ret_conv[1].replace("\n", "\n\t\t\t") + "\n")
1041                     out_c += "\treturn " + field_map.ret_conv_name + ";\n"
1042                 else:
1043                     if var.tuple_variant:
1044                         out_c += "\treturn " + "obj->" + camel_to_snake(var.var_name) + ";\n"
1045                     else:
1046                         out_c += "\treturn " + "obj->" + camel_to_snake(var.var_name) + "." + field_map.arg_name + ";\n"
1047                 out_c += "}\n"
1048                 out_java += self.native_meth_decl(fn_name, field_map.java_ty) + "(long ptr);\n"
1049         out_java_enum += java_hu_class
1050         out_java_enum += java_hu_subclasses
1051         return (out_java, out_java_enum, out_c)
1052
1053     def map_opaque_struct(self, struct_name, struct_doc_comment):
1054         out_opaque_struct_human = ""
1055         out_opaque_struct_human += self.hu_struct_file_prefix
1056         out_opaque_struct_human += "\n/**\n * " + struct_doc_comment.replace("\n", "\n * ") + "\n */\n"
1057         hu_name = struct_name.replace("LDKC2Tuple", "TwoTuple").replace("LDKC3Tuple", "ThreeTuple").replace("LDK", "")
1058         out_opaque_struct_human += ("public class " + hu_name + " : CommonBase")
1059         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1060             out_opaque_struct_human += (", IDisposable")
1061         out_opaque_struct_human += (" {\n")
1062         out_opaque_struct_human += ("\tinternal " + hu_name + "(object _dummy, long ptr) : base(ptr) { }\n")
1063         if struct_name.startswith("LDKLocked") or struct_name.startswith("LDKReadOnly"):
1064             out_opaque_struct_human += ("\tpublic void Dispose() {\n")
1065         else:
1066             out_opaque_struct_human += ("\t~" + hu_name + "() {\n")
1067         out_opaque_struct_human += ("\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); }\n")
1068         out_opaque_struct_human += ("\t}\n\n")
1069         return out_opaque_struct_human
1070
1071     def map_tuple(self, struct_name):
1072         return self.map_opaque_struct(struct_name, "A Tuple")
1073
1074     def map_result(self, struct_name, res_map, err_map):
1075         human_ty = struct_name.replace("LDKCResult", "Result")
1076         java_hu_struct = ""
1077         java_hu_struct += self.hu_struct_file_prefix
1078         java_hu_struct += "public class " + human_ty + " : CommonBase {\n"
1079         java_hu_struct += "\t" + human_ty + "(object _dummy, long ptr) : base(ptr) { }\n"
1080         java_hu_struct += "\t~" + human_ty + "() {\n"
1081         java_hu_struct += "\t\tif (ptr != 0) { bindings." + struct_name.replace("LDK","") + "_free(ptr); }\n"
1082         java_hu_struct += "\t}\n\n"
1083         java_hu_struct += "\tinternal static " + human_ty + " constr_from_ptr(long ptr) {\n"
1084         java_hu_struct += "\t\tif (bindings." + struct_name.replace("LDK", "") + "_is_ok(ptr)) {\n"
1085         java_hu_struct += "\t\t\treturn new " + human_ty + "_OK(null, ptr);\n"
1086         java_hu_struct += "\t\t} else {\n"
1087         java_hu_struct += "\t\t\treturn new " + human_ty + "_Err(null, ptr);\n"
1088         java_hu_struct += "\t\t}\n"
1089         java_hu_struct += "\t}\n"
1090
1091         java_hu_struct += "\tpublic class " + human_ty + "_OK : " + human_ty + " {\n"
1092
1093         if res_map.java_hu_ty != "void":
1094             java_hu_struct += "\t\tpublic readonly " + res_map.java_hu_ty + " res;\n"
1095         java_hu_struct += "\t\tinternal " + human_ty + "_OK(object _dummy, long ptr) : base(_dummy, ptr) {\n"
1096         if res_map.java_hu_ty == "void":
1097             pass
1098         elif res_map.to_hu_conv is not None:
1099             java_hu_struct += "\t\t\t" + res_map.java_ty + " res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1100             java_hu_struct += "\t\t\t" + res_map.to_hu_conv.replace("\n", "\n\t\t\t")
1101             java_hu_struct += "\n\t\t\tthis.res = " + res_map.to_hu_conv_name + ";\n"
1102         else:
1103             java_hu_struct += "\t\t\tthis.res = bindings." + struct_name.replace("LDK", "") + "_get_ok(ptr);\n"
1104         java_hu_struct += "\t\t}\n"
1105         java_hu_struct += "\t}\n\n"
1106
1107         java_hu_struct += "\tpublic class " + human_ty + "_Err : " + human_ty + " {\n"
1108         if err_map.java_hu_ty != "void":
1109             java_hu_struct += "\t\tpublic readonly " + err_map.java_hu_ty + " err;\n"
1110         java_hu_struct += "\t\tinternal " + human_ty + "_Err(object _dummy, long ptr) : base(_dummy, ptr) {\n"
1111         if err_map.java_hu_ty == "void":
1112             pass
1113         elif err_map.to_hu_conv is not None:
1114             java_hu_struct += "\t\t\t" + err_map.java_ty + " err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1115             java_hu_struct += "\t\t\t" + err_map.to_hu_conv.replace("\n", "\n\t\t\t")
1116             java_hu_struct += "\n\t\t\tthis.err = " + err_map.to_hu_conv_name + ";\n"
1117         else:
1118             java_hu_struct += "\t\t\tthis.err = bindings." + struct_name.replace("LDK", "") + "_get_err(ptr);\n"
1119         java_hu_struct += "\t\t}\n"
1120
1121         java_hu_struct += "\t}\n\n"
1122         return java_hu_struct
1123
1124     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):
1125         arg_name_repl = lambda s, arg_name: s.replace(arg_name, "_" + arg_name) if arg_name == "lock" or arg_name == "event" or arg_name == "params" else s
1126         out_java = ""
1127         out_c = ""
1128         out_java_struct = None
1129
1130         out_java += self.native_meth_decl(method_name, return_type_info.java_ty) + "("
1131         out_c += (return_type_info.c_ty)
1132         if return_type_info.ret_conv is not None:
1133             ret_conv_pfx, ret_conv_sfx = return_type_info.ret_conv
1134         have_args = len(argument_types) > 1 or (len(argument_types) > 0 and argument_types[0].c_ty != "void")
1135         out_c += (" " + self.c_fn_name_define_pfx(method_name, have_args))
1136
1137         for idx, arg_conv_info in enumerate(argument_types):
1138             if idx != 0:
1139                 out_java += (", ")
1140                 out_c += (", ")
1141             if arg_conv_info.c_ty != "void":
1142                 out_c += (arg_conv_info.c_ty + " " + arg_conv_info.arg_name)
1143                 if "[]" in arg_conv_info.java_ty:
1144                     out_java += "[MarshalAs(UnmanagedType.CustomMarshaler, MarshalType=\"org.ldk.impl.ArrayCoder\")] "
1145                 out_java += (arg_conv_info.java_ty + " _" + arg_conv_info.arg_name) # Add a _ to avoid using reserved words
1146
1147         out_java_struct = ""
1148         extra_java_struct_out = ""
1149         if not args_known:
1150             out_java_struct += ("\t// Skipped " + method_name + "\n")
1151         else:
1152             if doc_comment is not None:
1153                 out_java_struct += "\t/**\n\t * " + doc_comment.replace("\n", "\n\t * ") + "\n\t */\n"
1154             hu_ret_ty = return_type_info.java_hu_ty
1155             if return_type_info.nullable:
1156                 #hu_ret_ty += "?" - apparently mono doesn't support the nullable stuff
1157                 pass
1158             if not takes_self:
1159                 if meth_n == "new":
1160                     out_java_struct += "\tpublic static " + hu_ret_ty + " of("
1161                 elif meth_n == "default":
1162                     out_java_struct += "\tpublic static " + hu_ret_ty + " with_default("
1163                 else:
1164                     out_java_struct += "\tpublic static " + hu_ret_ty + " " + meth_n + "("
1165             elif meth_n == "clone_ptr" or (struct_meth.startswith("LDKCResult") and (meth_n == "get_ok" or meth_n == "get_err")):
1166                 out_java_struct += "\tinternal " + hu_ret_ty + " " + meth_n + "("
1167             else:
1168                 if meth_n == "hash" and return_type_info.java_hu_ty == "long":
1169                     extra_java_struct_out = "\tpublic override int GetHashCode() {\n"
1170                     extra_java_struct_out += "\t\treturn (int)this.hash();\n"
1171                     extra_java_struct_out += "\t}\n"
1172                 elif meth_n == "eq" and return_type_info.java_hu_ty == "bool":
1173                     extra_java_struct_out = "\tpublic override bool Equals(object o) {\n"
1174                     extra_java_struct_out += "\t\tif (!(o is " + struct_meth + ")) return false;\n"
1175                     extra_java_struct_out += "\t\treturn this.eq((" + struct_meth + ")o);\n"
1176                     extra_java_struct_out += "\t}\n"
1177                 if meth_n == "lock":
1178                     out_java_struct += "\tpublic " + hu_ret_ty + " do_lock("
1179                 else:
1180                     out_java_struct += "\tpublic " + hu_ret_ty + " " + meth_n + "("
1181             for idx, arg in enumerate(argument_types):
1182                 if idx != 0:
1183                     if not takes_self or idx > 1:
1184                         out_java_struct += ", "
1185                 elif takes_self:
1186                     continue
1187                 if arg.java_ty != "void":
1188                     if arg.arg_name in default_constructor_args:
1189                         assert not arg.nullable
1190                         for explode_idx, explode_arg in enumerate(default_constructor_args[arg.arg_name]):
1191                             if explode_idx != 0:
1192                                 out_java_struct += (", ")
1193                             out_java_struct += (
1194                                 explode_arg.java_hu_ty + " " + arg.arg_name + "_" + explode_arg.arg_name)
1195                     else:
1196                         ty_string = arg.java_hu_ty
1197                         if arg.nullable:
1198                             #ty_string += "?" - apparently mono doesn't support the nullable stuff
1199                             pass
1200                         ty_string = self.fully_qualified_hu_ty_path(arg)
1201                         out_java_struct += ty_string + " " + arg_name_repl(arg.arg_name, arg.arg_name)
1202         out_java += (");\n")
1203         out_c += (") {\n")
1204         if out_java_struct is not None:
1205             out_java_struct += (") {\n")
1206         for info in argument_types:
1207             if info.arg_conv is not None:
1208                 out_c += ("\t" + info.arg_conv.replace('\n', "\n\t") + "\n")
1209         if return_type_info.ret_conv is not None:
1210             out_c += ("\t" + ret_conv_pfx.replace('\n', '\n\t'))
1211         elif return_type_info.c_ty != "void":
1212             out_c += ("\t" + return_type_info.c_ty + " ret_val = ")
1213         else:
1214             out_c += ("\t")
1215         if c_call_string is None:
1216             out_c += (method_name + "(")
1217         else:
1218             out_c += (c_call_string)
1219         for idx, info in enumerate(argument_types):
1220             if info.arg_conv_name is not None:
1221                 if idx != 0:
1222                     out_c += (", ")
1223                 elif c_call_string is not None:
1224                     continue
1225                 out_c += (info.arg_conv_name)
1226         out_c += (")")
1227         if return_type_info.ret_conv is not None:
1228             out_c += (ret_conv_sfx.replace('\n', '\n\t'))
1229         else:
1230             out_c += (";")
1231         for info in argument_types:
1232             if info.arg_conv_cleanup is not None:
1233                 out_c += ("\n\t" + info.arg_conv_cleanup.replace("\n", "\n\t"))
1234         if return_type_info.ret_conv is not None:
1235             out_c += ("\n\treturn " + return_type_info.ret_conv_name + ";")
1236         elif return_type_info.c_ty != "void":
1237             out_c += ("\n\treturn ret_val;")
1238         out_c += ("\n}\n\n")
1239
1240         if args_known:
1241             out_java_struct += ("\t\t")
1242             if return_type_info.java_ty != "void":
1243                 out_java_struct += (return_type_info.java_ty + " ret = ")
1244             out_java_struct += ("bindings." + method_name + "(")
1245             for idx, info in enumerate(argument_types):
1246                 if idx != 0:
1247                     out_java_struct += (", ")
1248                 if idx == 0 and takes_self:
1249                     out_java_struct += ("this.ptr")
1250                 elif info.arg_name in default_constructor_args:
1251                     out_java_struct += ("bindings." + info.java_hu_ty + "_new(")
1252                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1253                         if explode_idx != 0:
1254                             out_java_struct += (", ")
1255                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1256                         if explode_arg.from_hu_conv is not None:
1257                             out_java_struct += (
1258                                 explode_arg.from_hu_conv[0].replace(explode_arg.arg_name, expl_arg_name))
1259                         else:
1260                             out_java_struct += (expl_arg_name)
1261                     out_java_struct += (")")
1262                 elif info.from_hu_conv is not None:
1263                     out_java_struct += arg_name_repl(info.from_hu_conv[0], info.arg_name)
1264                 else:
1265                     out_java_struct += arg_name_repl(info.arg_name, info.arg_name)
1266             out_java_struct += (");\n")
1267
1268             # Like Java, the C# GC is quite aggressive and can finalize an object while a method
1269             # on it is operating. Unlike Java, this behavior appears to be better documented,
1270             # which is nice.
1271             for idx, info in enumerate(argument_types):
1272                 if idx == 0 and takes_self:
1273                     out_java_struct += ("\t\tGC.KeepAlive(this);\n")
1274                 elif info.arg_name in default_constructor_args:
1275                     for explode_idx, explode_arg in enumerate(default_constructor_args[info.arg_name]):
1276                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1277                         out_java_struct += ("\t\tGC.KeepAlive(" + expl_arg_name + ");\n")
1278                 elif info.c_ty != "void":
1279                     out_java_struct += ("\t\tGC.KeepAlive(" + arg_name_repl(info.arg_name, info.arg_name) + ");\n")
1280
1281             if return_type_info.java_ty == "long" and return_type_info.java_hu_ty != "long":
1282                 out_java_struct += "\t\tif (ret >= 0 && ret <= 4096) { return null; }\n"
1283
1284             if return_type_info.to_hu_conv is not None:
1285                 if not takes_self:
1286                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t")
1287                         .replace("this", return_type_info.to_hu_conv_name) + "\n")
1288                 else:
1289                     out_java_struct += ("\t\t" + return_type_info.to_hu_conv.replace("\n", "\n\t\t") + "\n")
1290
1291             for idx, info in enumerate(argument_types):
1292                 if idx == 0 and takes_self:
1293                     pass
1294                 elif info.arg_name in default_constructor_args:
1295                     for explode_arg in default_constructor_args[info.arg_name]:
1296                         expl_arg_name = info.arg_name + "_" + explode_arg.arg_name
1297                         if explode_arg.from_hu_conv is not None and return_type_info.to_hu_conv_name:
1298                             out_java_struct += ("\t\t" +
1299                                 arg_name_repl(explode_arg.from_hu_conv[1], info.arg_name)
1300                                 .replace(explode_arg.arg_name, expl_arg_name)
1301                                 .replace("this", return_type_info.to_hu_conv_name) + ";\n")
1302                 elif info.from_hu_conv is not None and info.from_hu_conv[1] != "":
1303                     if not takes_self and return_type_info.to_hu_conv_name is not None:
1304                         out_java_struct += ("\t\t" + arg_name_repl(info.from_hu_conv[1], info.arg_name)
1305                             .replace("this", return_type_info.to_hu_conv_name)
1306                             .replace("\n", "\n\t\t") + ";\n")
1307                     else:
1308                         out_java_struct += ("\t\t" + arg_name_repl(info.from_hu_conv[1], info.arg_name)
1309                             .replace("\n", "\n\t\t") + ";\n")
1310
1311             if takes_self and not takes_self_as_ref:
1312                 out_java_struct += "\t\t" + argument_types[0].from_hu_conv[1].replace("\n", "\n\t\t").replace("this_arg", "this") + ";\n"
1313             if return_type_info.to_hu_conv_name is not None:
1314                 out_java_struct += ("\t\treturn " + return_type_info.to_hu_conv_name + ";\n")
1315             elif return_type_info.java_ty != "void" and return_type_info.rust_obj != "LDK" + struct_meth:
1316                 out_java_struct += ("\t\treturn ret;\n")
1317             out_java_struct += ("\t}\n\n")
1318
1319         return (out_java, out_c, out_java_struct + extra_java_struct_out)
1320
1321     def cleanup(self):
1322         pass