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

   1 #!/usr/bin/env python3
   2 import sys, re
   3
   4 if len(sys.argv) != 5:
   5     print("USAGE: /path/to/lightning.h /path/to/bindings/output.java /path/to/bindings/output.c debug")
   6     print("debug should be true or false and indicates whether to track allocations and ensure we don't leak")
   7     sys.exit(1)
   8
   9 class TypeInfo:
  10     def __init__(self, rust_obj, java_ty, java_fn_ty_arg, c_ty, passed_as_ptr, is_ptr, var_name, arr_len):
  11         self.rust_obj = rust_obj
  12         self.java_ty = java_ty
  13         self.java_fn_ty_arg = java_fn_ty_arg
  14         self.c_ty = c_ty
  15         self.passed_as_ptr = passed_as_ptr
  16         self.is_ptr = is_ptr
  17         self.var_name = var_name
  18         self.arr_len = arr_len
  19
  20 class ConvInfo:
  21     def __init__(self, ty_info, arg_name, arg_conv, arg_conv_name, ret_conv, ret_conv_name):
  22         assert(ty_info.c_ty is not None)
  23         assert(ty_info.java_ty is not None)
  24         assert(arg_name is not None)
  25         self.c_ty = ty_info.c_ty
  26         self.java_ty = ty_info.java_ty
  27         self.java_fn_ty_arg = ty_info.java_fn_ty_arg
  28         self.arg_name = arg_name
  29         self.arg_conv = arg_conv
  30         self.arg_conv_name = arg_conv_name
  31         self.ret_conv = ret_conv
  32         self.ret_conv_name = ret_conv_name
  33
  34     def print_ty(self):
  35         out_c.write(self.c_ty)
  36         out_java.write(self.java_ty)
  37
  38     def print_name(self):
  39         if self.arg_name != "":
  40             out_java.write(" " + self.arg_name)
  41             out_c.write(" " + self.arg_name)
  42         else:
  43             out_java.write(" arg")
  44             out_c.write(" arg")
  45
  46 with open(sys.argv[1]) as in_h, open(sys.argv[2], "w") as out_java, open(sys.argv[3], "w") as out_c:
  47     opaque_structs = set()
  48     trait_structs = set()
  49
  50     var_is_arr_regex = re.compile("\(\*([A-za-z_]*)\)\[([0-9]*)\]")
  51     var_ty_regex = re.compile("([A-za-z_0-9]*)(.*)")
  52     def java_c_types(fn_arg, ret_arr_len):
  53         fn_arg = fn_arg.strip()
  54         if fn_arg.startswith("MUST_USE_RES "):
  55             fn_arg = fn_arg[13:]
  56         is_const = False
  57         if fn_arg.startswith("const "):
  58             fn_arg = fn_arg[6:]
  59             is_const = True
  60
  61         is_ptr = False
  62         take_by_ptr = False
  63         rust_obj = None
  64         if fn_arg.startswith("void"):
  65             java_ty = "void"
  66             c_ty = "void"
  67             fn_ty_arg = "V"
  68             fn_arg = fn_arg[4:].strip()
  69         elif fn_arg.startswith("bool"):
  70             java_ty = "boolean"
  71             c_ty = "jboolean"
  72             fn_ty_arg = "Z"
  73             fn_arg = fn_arg[4:].strip()
  74         elif fn_arg.startswith("uint8_t"):
  75             java_ty = "byte"
  76             c_ty = "jbyte"
  77             fn_ty_arg = "B"
  78             fn_arg = fn_arg[7:].strip()
  79         elif fn_arg.startswith("uint16_t"):
  80             java_ty = "short"
  81             c_ty = "jshort"
  82             fn_ty_arg = "S"
  83             fn_arg = fn_arg[8:].strip()
  84         elif fn_arg.startswith("uint32_t"):
  85             java_ty = "int"
  86             c_ty = "jint"
  87             fn_ty_arg = "I"
  88             fn_arg = fn_arg[8:].strip()
  89         elif fn_arg.startswith("uint64_t"):
  90             java_ty = "long"
  91             c_ty = "jlong"
  92             fn_ty_arg = "J"
  93             fn_arg = fn_arg[8:].strip()
  94         elif is_const and fn_arg.startswith("char *"):
  95             java_ty = "String"
  96             c_ty = "const char*"
  97             fn_ty_arg = "Ljava/lang/String;"
  98             fn_arg = fn_arg[6:].strip()
  99         else:
 100             ma = var_ty_regex.match(fn_arg)
 101             java_ty = "long"
 102             c_ty = "jlong"
 103             fn_ty_arg = "J"
 104             fn_arg = ma.group(2).strip()
 105             rust_obj = ma.group(1).strip()
 106             take_by_ptr = True
 107
 108         if fn_arg.startswith(" *") or fn_arg.startswith("*"):
 109             fn_arg = fn_arg.replace("*", "").strip()
 110             is_ptr = True
 111             c_ty = "jlong"
 112             java_ty = "long"
 113
 114         var_is_arr = var_is_arr_regex.match(fn_arg)
 115         if var_is_arr is not None or ret_arr_len is not None:
 116             assert(not take_by_ptr)
 117             assert(not is_ptr)
 118             java_ty = java_ty + "[]"
 119             c_ty = c_ty + "Array"
 120             if var_is_arr is not None:
 121                 return TypeInfo(rust_obj=None, java_ty=java_ty, java_fn_ty_arg="[" + fn_ty_arg, c_ty=c_ty,
 122                     passed_as_ptr=False, is_ptr=False, var_name=var_is_arr.group(1), arr_len=var_is_arr.group(2))
 123         return TypeInfo(rust_obj=rust_obj, java_ty=java_ty, java_fn_ty_arg=fn_ty_arg, c_ty=c_ty, passed_as_ptr=is_ptr or take_by_ptr,
 124             is_ptr=is_ptr, var_name=fn_arg, arr_len=None)
 125
 126     def map_type(fn_arg, print_void, ret_arr_len, is_free):
 127         ty_info = java_c_types(fn_arg, ret_arr_len)
 128
 129         if ty_info.c_ty == "void":
 130             if not print_void:
 131                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 132                     arg_conv = None, arg_conv_name = None, ret_conv = None, ret_conv_name = None)
 133
 134         if ty_info.c_ty.endswith("Array"):
 135             arr_len = ty_info.arr_len
 136             if arr_len is not None:
 137                 arr_name = ty_info.var_name
 138             else:
 139                 arr_name = "ret"
 140                 arr_len = ret_arr_len
 141             assert(ty_info.c_ty == "jbyteArray")
 142             return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 143                 arg_conv = "unsigned char " + arr_name + "_arr[" + arr_len + "];\n" +
 144                     "(*_env)->GetByteArrayRegion (_env, """ + arr_name + ", 0, " + arr_len + ", " + arr_name + "_arr);\n" +
 145                     "unsigned char (*""" + arr_name + "_ref)[" + arr_len + "] = &" + arr_name + "_arr;",
 146                 arg_conv_name = arr_name + "_ref",
 147                 ret_conv = ("jbyteArray " + arr_name + "_arr = (*_env)->NewByteArray(_env, " + arr_len + ");\n" +
 148                     "(*_env)->SetByteArrayRegion(_env, " + arr_name + "_arr, 0, " + arr_len + ", *",
 149                     ");"),
 150                 ret_conv_name = arr_name + "_arr")
 151         elif ty_info.var_name != "":
 152             # If we have a parameter name, print it (noting that it may indicate its a pointer)
 153             if ty_info.rust_obj is not None:
 154                 assert(ty_info.passed_as_ptr)
 155                 if not ty_info.is_ptr:
 156                     base_conv = ty_info.rust_obj + " " + ty_info.var_name + "_conv = *(" + ty_info.rust_obj + "*)" + ty_info.var_name + ";";
 157                     if ty_info.rust_obj in trait_structs:
 158                         if not is_free:
 159                             base_conv = base_conv + "\n" + ty_info.rust_obj + "_JCalls_clone(" + ty_info.var_name + "_conv.this_arg);"
 160                         else:
 161                             base_conv = base_conv + "\n" + "FREE((void*)" + ty_info.var_name + ");"
 162                         return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 163                             arg_conv = base_conv,
 164                             arg_conv_name = ty_info.var_name + "_conv",
 165                             ret_conv = None, ret_conv_name = None)
 166                     base_conv = base_conv + "\nFREE((void*)" + ty_info.var_name + ");";
 167                     if ty_info.rust_obj in opaque_structs:
 168                         return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 169                             arg_conv = base_conv + "\n" + ty_info.var_name + "_conv._underlying_ref = false;",
 170                             arg_conv_name = ty_info.var_name + "_conv",
 171                             ret_conv = None, ret_conv_name = None)
 172
 173                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 174                         arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv",
 175                         ret_conv = None, ret_conv_name = None)
 176                 else:
 177                     assert(not is_free)
 178                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 179                         arg_conv = ty_info.rust_obj + "* " + ty_info.var_name + "_conv = (" + ty_info.rust_obj + "*)" + ty_info.var_name + ";",
 180                         arg_conv_name = ty_info.var_name + "_conv",
 181                         ret_conv = None, ret_conv_name = None)
 182             elif ty_info.is_ptr:
 183                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 184                     arg_conv = None, arg_conv_name = ty_info.var_name, ret_conv = None, ret_conv_name = None)
 185             elif ty_info.java_ty == "String":
 186                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 187                     arg_conv = None, arg_conv_name = None,
 188                     ret_conv = ("jstring " + ty_info.var_name + "_conv = (*_env)->NewStringUTF(_env, ", ");"), ret_conv_name = ty_info.var_name + "_conv")
 189             else:
 190                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 191                     arg_conv = None, arg_conv_name = ty_info.var_name, ret_conv = None, ret_conv_name = None)
 192         elif not print_void:
 193             # We don't have a parameter name, and want one, just call it arg
 194             if ty_info.rust_obj is not None:
 195                 assert(not is_free or ty_info.rust_obj not in opaque_structs);
 196                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 197                     arg_conv = ty_info.rust_obj + " arg_conv = *(" + ty_info.rust_obj + "*)arg;\nFREE((void*)arg);",
 198                     arg_conv_name = "arg_conv",
 199                     ret_conv = None, ret_conv_name = None)
 200             else:
 201                 assert(not is_free)
 202                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 203                     arg_conv = None, arg_conv_name = "arg", ret_conv = None, ret_conv_name = None)
 204         else:
 205             # We don't have a parameter name, and don't want one (cause we're returning)
 206             if ty_info.rust_obj is not None:
 207                 if not ty_info.is_ptr:
 208                     if ty_info.rust_obj in opaque_structs:
 209                         # If we're returning a newly-allocated struct, we don't want Rust to ever
 210                         # free, instead relying on the Java GC to lose the ref. We undo this in
 211                         # any _free function.
 212                         # To avoid any issues, we first assert that the incoming object is non-ref.
 213                         return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 214                             ret_conv = (ty_info.rust_obj + "* ret = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*ret = ", ";\nassert(!ret->_underlying_ref);\nret->_underlying_ref = true;"),
 215                             ret_conv_name = "(long)ret",
 216                             arg_conv = None, arg_conv_name = None)
 217                     else:
 218                         return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 219                             ret_conv = (ty_info.rust_obj + "* ret = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*ret = ", ";"),
 220                             ret_conv_name = "(long)ret",
 221                             arg_conv = None, arg_conv_name = None)
 222                 else:
 223                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 224                         ret_conv = ("long ret = (long)", ";"), ret_conv_name = "ret",
 225                         arg_conv = None, arg_conv_name = None)
 226             else:
 227                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 228                     arg_conv = None, arg_conv_name = None, ret_conv = None, ret_conv_name = None)
 229
 230     def map_fn(re_match, ret_arr_len):
 231         out_java.write("\t/// " + line)
 232         out_java.write("\tpublic static native ")
 233         out_c.write("JNIEXPORT ")
 234
 235         ret_info = map_type(re_match.group(1), True, ret_arr_len, False)
 236         ret_info.print_ty()
 237         if ret_info.ret_conv is not None:
 238             ret_conv_pfx, ret_conv_sfx = ret_info.ret_conv
 239
 240         out_java.write(" " + re_match.group(2) + "(")
 241         out_c.write(" JNICALL Java_org_ldk_impl_bindings_" + re_match.group(2).replace('_', '_1') + "(JNIEnv * _env, jclass _b")
 242
 243         arg_names = []
 244         for idx, arg in enumerate(re_match.group(3).split(',')):
 245             if idx != 0:
 246                 out_java.write(", ")
 247             if arg != "void":
 248                 out_c.write(", ")
 249             arg_conv_info = map_type(arg, False, None, re_match.group(2).endswith("_free"))
 250             if arg_conv_info.c_ty != "void":
 251                 arg_conv_info.print_ty()
 252                 arg_conv_info.print_name()
 253             arg_names.append(arg_conv_info)
 254
 255         out_java.write(");\n")
 256         out_c.write(") {\n")
 257
 258         for info in arg_names:
 259             if info.arg_conv is not None:
 260                 out_c.write("\t" + info.arg_conv.replace('\n', "\n\t") + "\n");
 261
 262         if ret_info.ret_conv is not None:
 263             out_c.write("\t" + ret_conv_pfx.replace('\n', '\n\t'));
 264         else:
 265             out_c.write("\treturn ");
 266
 267         out_c.write(re_match.group(2) + "(")
 268         for idx, info in enumerate(arg_names):
 269             if info.arg_conv_name is not None:
 270                 if idx != 0:
 271                     out_c.write(", ")
 272                 out_c.write(info.arg_conv_name)
 273         out_c.write(")")
 274         if ret_info.ret_conv is not None:
 275             out_c.write(ret_conv_sfx.replace('\n', '\n\t'))
 276             out_c.write("\n\treturn " + ret_info.ret_conv_name + ";")
 277         else:
 278             out_c.write(";")
 279         out_c.write("\n}\n\n")
 280
 281     def map_trait(struct_name, field_var_lines, trait_fn_lines):
 282         out_c.write("typedef struct " + struct_name + "_JCalls {\n")
 283         out_c.write("\tatomic_size_t refcnt;\n")
 284         out_c.write("\tJNIEnv *env;\n")
 285         out_c.write("\tjobject o;\n")
 286         for var_line in field_var_lines:
 287             if var_line.group(1) in trait_structs:
 288                 out_c.write("\t" + var_line.group(1) + "_JCalls* " + var_line.group(2) + ";\n")
 289         for fn_line in trait_fn_lines:
 290             if fn_line.group(2) != "free" and fn_line.group(2) != "clone":
 291                 out_c.write("\tjmethodID " + fn_line.group(2) + "_meth;\n")
 292         out_c.write("} " + struct_name + "_JCalls;\n")
 293
 294         out_java.write("\tpublic interface " + struct_name + " {\n")
 295         java_meths = []
 296         for fn_line in trait_fn_lines:
 297             java_meth_descr = "("
 298             if fn_line.group(2) != "free" and fn_line.group(2) != "clone":
 299                 ret_ty_info = java_c_types(fn_line.group(1), None)
 300
 301                 out_java.write("\t\t " + ret_ty_info.java_ty + " " + fn_line.group(2) + "(")
 302                 is_const = fn_line.group(3) is not None
 303                 out_c.write(fn_line.group(1) + fn_line.group(2) + "_jcall(")
 304                 if is_const:
 305                     out_c.write("const void* this_arg")
 306                 else:
 307                     out_c.write("void* this_arg")
 308
 309                 arg_names = []
 310                 for idx, arg in enumerate(fn_line.group(4).split(',')):
 311                     if arg == "":
 312                         continue
 313                     if idx >= 2:
 314                         out_java.write(", ")
 315                     out_c.write(", ")
 316                     arg_conv_info = map_type(arg, True, None, False)
 317                     out_c.write(arg.strip())
 318                     out_java.write(arg_conv_info.java_ty + " " + arg_conv_info.arg_name)
 319                     arg_names.append(arg_conv_info)
 320                     java_meth_descr = java_meth_descr + arg_conv_info.java_fn_ty_arg
 321                 java_meth_descr = java_meth_descr + ")" + ret_ty_info.java_fn_ty_arg
 322                 java_meths.append(java_meth_descr)
 323
 324                 out_java.write(");\n")
 325                 out_c.write(") {\n")
 326                 out_c.write("\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n")
 327
 328                 for arg_info in arg_names:
 329                     if arg_info.ret_conv is not None:
 330                         out_c.write("\t" + arg_info.ret_conv[0].replace('\n', '\n\t').replace("_env", "j_calls->env"));
 331                         out_c.write(arg_info.arg_name)
 332                         out_c.write(arg_info.ret_conv[1].replace('\n', '\n\t').replace("_env", "j_calls->env") + "\n")
 333
 334                 if not ret_ty_info.passed_as_ptr:
 335                     out_c.write("\treturn (*j_calls->env)->Call" + ret_ty_info.java_ty.title() + "Method(j_calls->env, j_calls->o, j_calls->" + fn_line.group(2) + "_meth")
 336                 else:
 337                     out_c.write("\t" + fn_line.group(1).strip() + "* ret = (" + fn_line.group(1).strip() + "*)(*j_calls->env)->CallLongMethod(j_calls->env, j_calls->o, j_calls->" + fn_line.group(2) + "_meth");
 338
 339                 for arg_info in arg_names:
 340                     if arg_info.ret_conv is not None:
 341                         out_c.write(", " + arg_info.ret_conv_name)
 342                     else:
 343                         out_c.write(", " + arg_info.arg_name)
 344                 out_c.write(");\n");
 345
 346                 if ret_ty_info.passed_as_ptr:
 347                     out_c.write("\t" + fn_line.group(1).strip() + " res = *ret;\n")
 348                     out_c.write("\tFREE(ret);\n")
 349                     out_c.write("\treturn res;\n")
 350                 out_c.write("}\n")
 351             elif fn_line.group(2) == "free":
 352                 out_c.write("static void " + struct_name + "_JCalls_free(void* this_arg) {\n")
 353                 out_c.write("\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n")
 354                 out_c.write("\tif (atomic_fetch_sub_explicit(&j_calls->refcnt, 1, memory_order_acquire) == 1) {\n")
 355                 out_c.write("\t\t(*j_calls->env)->DeleteGlobalRef(j_calls->env, j_calls->o);\n")
 356                 out_c.write("\t\tFREE(j_calls);\n")
 357                 out_c.write("\t}\n}\n")
 358
 359         # Write out a clone function whether we need one or not, as we use them in moving to rust
 360         out_c.write("static void* " + struct_name + "_JCalls_clone(const void* this_arg) {\n")
 361         out_c.write("\t" + struct_name + "_JCalls *j_calls = (" + struct_name + "_JCalls*) this_arg;\n")
 362         out_c.write("\tatomic_fetch_add_explicit(&j_calls->refcnt, 1, memory_order_release);\n")
 363         for var_line in field_var_lines:
 364             if var_line.group(1) in trait_structs:
 365                 out_c.write("\tatomic_fetch_add_explicit(&j_calls->" + var_line.group(2) + "->refcnt, 1, memory_order_release);\n")
 366         out_c.write("\treturn (void*) this_arg;\n")
 367         out_c.write("}\n")
 368
 369         out_java.write("\t}\n")
 370
 371         out_java.write("\tpublic static native long " + struct_name + "_new(" + struct_name + " impl")
 372         out_c.write("static inline " + struct_name + " " + struct_name + "_init (JNIEnv * env, jclass _a, jobject o")
 373         for var_line in field_var_lines:
 374             if var_line.group(1) in trait_structs:
 375                 out_java.write(", " + var_line.group(1) + " " + var_line.group(2))
 376                 out_c.write(", jobject " + var_line.group(2))
 377         out_java.write(");\n")
 378         out_c.write(") {\n")
 379
 380         out_c.write("\tjclass c = (*env)->GetObjectClass(env, o);\n")
 381         out_c.write("\tassert(c != NULL);\n")
 382         out_c.write("\t" + struct_name + "_JCalls *calls = MALLOC(sizeof(" + struct_name + "_JCalls), \"" + struct_name + "_JCalls\");\n")
 383         out_c.write("\tatomic_init(&calls->refcnt, 1);\n")
 384         out_c.write("\tcalls->env = env;\n")
 385         out_c.write("\tcalls->o = (*env)->NewGlobalRef(env, o);\n")
 386         for (fn_line, java_meth_descr) in zip(trait_fn_lines, java_meths):
 387             if fn_line.group(2) != "free" and fn_line.group(2) != "clone":
 388                 out_c.write("\tcalls->" + fn_line.group(2) + "_meth = (*env)->GetMethodID(env, c, \"" + fn_line.group(2) + "\", \"" + java_meth_descr + "\");\n")
 389                 out_c.write("\tassert(calls->" + fn_line.group(2) + "_meth != NULL);\n")
 390         out_c.write("\n\t" + struct_name + " ret = {\n")
 391         out_c.write("\t\t.this_arg = (void*) calls,\n")
 392         for fn_line in trait_fn_lines:
 393             if fn_line.group(2) != "free" and fn_line.group(2) != "clone":
 394                 out_c.write("\t\t." + fn_line.group(2) + " = " + fn_line.group(2) + "_jcall,\n")
 395             elif fn_line.group(2) == "free":
 396                 out_c.write("\t\t.free = " + struct_name + "_JCalls_free,\n")
 397             else:
 398                 out_c.write("\t\t.clone = " + struct_name + "_JCalls_clone,\n")
 399         for var_line in field_var_lines:
 400             if var_line.group(1) in trait_structs:
 401                 out_c.write("\t\t." + var_line.group(2) + " = " + var_line.group(1) + "_init(env, _a, " + var_line.group(2) + "),\n")
 402         out_c.write("\t};\n")
 403         for var_line in field_var_lines:
 404             if var_line.group(1) in trait_structs:
 405                 out_c.write("\tcalls->" + var_line.group(2) + " = ret." + var_line.group(2) + ".this_arg;\n")
 406         out_c.write("\treturn ret;\n")
 407         out_c.write("}\n")
 408
 409         out_c.write("JNIEXPORT long JNICALL Java_org_ldk_impl_bindings_" + struct_name.replace("_", "_1") + "_1new (JNIEnv * env, jclass _a, jobject o")
 410         for var_line in field_var_lines:
 411             if var_line.group(1) in trait_structs:
 412                 out_c.write(", jobject " + var_line.group(2))
 413         out_c.write(") {\n")
 414         out_c.write("\t" + struct_name + " *res_ptr = MALLOC(sizeof(" + struct_name + "), \"" + struct_name + "\");\n")
 415         out_c.write("\t*res_ptr = " + struct_name + "_init(env, _a, o")
 416         for var_line in field_var_lines:
 417             if var_line.group(1) in trait_structs:
 418                 out_c.write(", " + var_line.group(2))
 419         out_c.write(");\n")
 420         out_c.write("\treturn (long)res_ptr;\n")
 421         out_c.write("}\n")
 422
 423
 424
 425     out_java.write("""package org.ldk.impl;
 426
 427 public class bindings {
 428         static {
 429                 System.loadLibrary(\"lightningjni\");
 430         }
 431
 432 """)
 433     out_c.write("#include \"org_ldk_impl_bindings.h\"\n")
 434     out_c.write("#include <rust_types.h>\n")
 435     out_c.write("#include <lightning.h>\n")
 436     out_c.write("#include <assert.h>\n")
 437     out_c.write("#include <string.h>\n")
 438     out_c.write("#include <stdatomic.h>\n\n")
 439     if sys.argv[4] == "false":
 440         out_c.write("#define MALLOC(a, _) malloc(a)\n")
 441         out_c.write("#define FREE free\n\n")
 442     else:
 443         out_c.write("#include <threads.h>\n")
 444         out_c.write("static mtx_t allocation_mtx;\n\n")
 445         out_c.write("void __attribute__((constructor)) init_mtx() {\n")
 446         out_c.write("\tassert(mtx_init(&allocation_mtx, mtx_plain) == thrd_success);\n")
 447         out_c.write("}\n\n")
 448         out_c.write("typedef struct allocation {\n")
 449         out_c.write("\tstruct allocation* next;\n")
 450         out_c.write("\tvoid* ptr;\n")
 451         out_c.write("\tconst char* struct_name;\n")
 452         out_c.write("} allocation;\n")
 453         out_c.write("static allocation* allocation_ll = NULL;\n\n")
 454         out_c.write("void* MALLOC(size_t len, const char* struct_name) {\n")
 455         out_c.write("\tvoid* res = malloc(len);\n")
 456         out_c.write("\tallocation* new_alloc = malloc(sizeof(allocation));\n")
 457         out_c.write("\tnew_alloc->ptr = res;\n")
 458         out_c.write("\tnew_alloc->struct_name = struct_name;\n")
 459         out_c.write("\tassert(mtx_lock(&allocation_mtx) == thrd_success);\n")
 460         out_c.write("\tnew_alloc->next = allocation_ll;\n")
 461         out_c.write("\tallocation_ll = new_alloc;\n")
 462         out_c.write("\tassert(mtx_unlock(&allocation_mtx) == thrd_success);\n")
 463         out_c.write("\treturn res;\n")
 464         out_c.write("}\n\n")
 465         out_c.write("void FREE(void* ptr) {\n")
 466         out_c.write("\tallocation* p = NULL;\n")
 467         out_c.write("\tassert(mtx_lock(&allocation_mtx) == thrd_success);\n")
 468         out_c.write("\tallocation* it = allocation_ll;\n")
 469         out_c.write("\twhile (it->ptr != ptr) { p = it; it = it->next; }\n")
 470         out_c.write("\tif (p) { p->next = it->next; } else { allocation_ll = it->next; }\n")
 471         out_c.write("\tassert(mtx_unlock(&allocation_mtx) == thrd_success);\n")
 472         out_c.write("\tassert(it->ptr == ptr);\n")
 473         out_c.write("\tfree(it);\n")
 474         out_c.write("\tfree(ptr);\n")
 475         out_c.write("}\n\n")
 476         out_c.write("void __attribute__((destructor)) check_leaks() {\n")
 477         out_c.write("\tfor (allocation* a = allocation_ll; a != NULL; a = a->next) { fprintf(stderr, \"%s %p remains\\n\", a->struct_name, a->ptr); }\n")
 478         out_c.write("\tassert(allocation_ll == NULL);\n")
 479         out_c.write("}\n\n")
 480
 481     # XXX: Temporarily write out a manual SecretKey_new() for testing, we should auto-gen this kind of thing
 482     out_java.write("\tpublic static native long LDKSecretKey_new();\n\n") # TODO: rm me
 483     out_c.write("JNIEXPORT jlong JNICALL Java_org_ldk_impl_bindings_LDKSecretKey_1new(JNIEnv * _env, jclass _b) {\n") # TODO: rm me
 484     out_c.write("\tLDKSecretKey* key = (LDKSecretKey*)MALLOC(sizeof(LDKSecretKey), \"LDKSecretKey\");\n") # TODO: rm me
 485     out_c.write("\treturn (long)key;\n") # TODO: rm me
 486     out_c.write("}\n") # TODO: rm me
 487
 488     in_block_comment = False
 489     in_block_enum = False
 490     cur_block_struct = None
 491     in_block_union = False
 492
 493     fn_ptr_regex = re.compile("^extern const ([A-Za-z_0-9\* ]*) \(\*(.*)\)\((.*)\);$")
 494     fn_ret_arr_regex = re.compile("(.*) \(\*(.*)\((.*)\)\)\[([0-9]*)\];$")
 495     reg_fn_regex = re.compile("([A-Za-z_0-9\* ]* \*?)([a-zA-Z_0-9]*)\((.*)\);$")
 496     const_val_regex = re.compile("^extern const ([A-Za-z_0-9]*) ([A-Za-z_0-9]*);$")
 497
 498     line_indicates_opaque_regex = re.compile("^   bool _underlying_ref;$")
 499     line_indicates_trait_regex = re.compile("^   ([A-Za-z_0-9]* \*?)\(\*([A-Za-z_0-9]*)\)\((const )?void \*this_arg(.*)\);$")
 500     assert(line_indicates_trait_regex.match("   uintptr_t (*send_data)(void *this_arg, LDKu8slice data, bool resume_read);"))
 501     assert(line_indicates_trait_regex.match("   LDKCVec_MessageSendEventZ (*get_and_clear_pending_msg_events)(const void *this_arg);"))
 502     assert(line_indicates_trait_regex.match("   void *(*clone)(const void *this_arg);"))
 503     line_field_var_regex = re.compile("^   ([A-Za-z_0-9]*) ([A-Za-z_0-9]*);$")
 504     assert(line_field_var_regex.match("   LDKMessageSendEventsProvider MessageSendEventsProvider;"))
 505     struct_name_regex = re.compile("^typedef (struct|enum) (MUST_USE_STRUCT )?(LDK[A-Za-z_0-9]*) {$")
 506     assert(struct_name_regex.match("typedef struct LDKCVecTempl_u8 {"))
 507     assert(struct_name_regex.match("typedef enum LDKNetwork {"))
 508
 509     for line in in_h:
 510         if in_block_comment:
 511             #out_java.write("\t" + line)
 512             if line.endswith("*/\n"):
 513                 in_block_comment = False
 514         elif cur_block_struct is not None:
 515             cur_block_struct  = cur_block_struct + line
 516             if line.startswith("} "):
 517                 field_lines = []
 518                 struct_name = None
 519                 struct_lines = cur_block_struct.split("\n")
 520                 is_opaque = False
 521                 trait_fn_lines = []
 522                 field_var_lines = []
 523
 524                 for idx, struct_line in enumerate(struct_lines):
 525                     if struct_line.strip().startswith("/*"):
 526                         in_block_comment = True
 527                     if in_block_comment:
 528                         if struct_line.endswith("*/"):
 529                             in_block_comment = False
 530                     else:
 531                         struct_name_match = struct_name_regex.match(struct_line)
 532                         if struct_name_match is not None:
 533                             struct_name = struct_name_match.group(2)
 534                         if line_indicates_opaque_regex.match(struct_line):
 535                             is_opaque = True
 536                         trait_fn_match = line_indicates_trait_regex.match(struct_line)
 537                         if trait_fn_match is not None:
 538                             trait_fn_lines.append(trait_fn_match)
 539                         field_var_match = line_field_var_regex.match(struct_line)
 540                         if field_var_match is not None:
 541                             field_var_lines.append(field_var_match)
 542                         field_lines.append(struct_line)
 543
 544                 assert(struct_name is not None)
 545                 assert(len(trait_fn_lines) == 0 or not is_opaque)
 546                 if is_opaque:
 547                     opaque_structs.add(struct_name)
 548                 if len(trait_fn_lines) > 0:
 549                     trait_structs.add(struct_name)
 550                     map_trait(struct_name, field_var_lines, trait_fn_lines)
 551                     #out_java.write("/* " + "\n".join(field_lines) + "*/\n")
 552                 cur_block_struct = None
 553         elif in_block_union:
 554             if line.startswith("} "):
 555                 in_block_union = False
 556         elif in_block_enum:
 557             if line.startswith("} "):
 558                 in_block_enum = False
 559         else:
 560             fn_ptr = fn_ptr_regex.match(line)
 561             fn_ret_arr = fn_ret_arr_regex.match(line)
 562             reg_fn = reg_fn_regex.match(line)
 563             const_val = const_val_regex.match(line)
 564
 565             if line.startswith("#include <"):
 566                 pass
 567             elif line.startswith("/*"):
 568                 #out_java.write("\t" + line)
 569                 if not line.endswith("*/\n"):
 570                     in_block_comment = True
 571             elif line.startswith("typedef enum "):
 572                 in_block_enum = True
 573             elif line.startswith("typedef struct "):
 574                 cur_block_struct = line
 575             elif line.startswith("typedef union "):
 576                 in_block_union = True
 577             elif line.startswith("typedef "):
 578                 pass
 579             elif fn_ptr is not None:
 580                 map_fn(fn_ptr, None)
 581             elif fn_ret_arr is not None:
 582                 map_fn(fn_ret_arr, fn_ret_arr.group(4))
 583             elif reg_fn is not None:
 584                 map_fn(reg_fn, None)
 585             elif const_val_regex is not None:
 586                 # TODO Map const variables
 587                 pass
 588             else:
 589                 assert(line == "\n")
 590
 591     out_java.write("}\n")