include/demangle.h

   1 /* Defs for interface to demanglers.
   2    Copyright (C) 1992-2023 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License
   6    as published by the Free Software Foundation; either version 2, or
   7    (at your option) any later version.
   8
   9    In addition to the permissions in the GNU Library General Public
  10    License, the Free Software Foundation gives you unlimited
  11    permission to link the compiled version of this file into
  12    combinations with other programs, and to distribute those
  13    combinations without any restriction coming from the use of this
  14    file.  (The Library Public License restrictions do apply in other
  15    respects; for example, they cover modification of the file, and
  16    distribution when not linked into a combined executable.)
  17
  18    This program is distributed in the hope that it will be useful, but
  19    WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21    Library General Public License for more details.
  22
  23    You should have received a copy of the GNU Library General Public
  24    License along with this program; if not, write to the Free Software
  25    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
  26    02110-1301, USA.  */
  27
  28
  29 #if !defined (DEMANGLE_H)
  30 #define DEMANGLE_H
  31
  32 #include "libiberty.h"
  33
  34 #ifdef __cplusplus
  35 extern "C" {
  36 #endif /* __cplusplus */
  37
  38 /* Options passed to cplus_demangle (in 2nd parameter). */
  39
  40 #define DMGL_NO_OPTS     0              /* For readability... */
  41 #define DMGL_PARAMS      (1 << 0)       /* Include function args */
  42 #define DMGL_ANSI        (1 << 1)       /* Include const, volatile, etc */
  43 #define DMGL_JAVA        (1 << 2)       /* Demangle as Java rather than C++. */
  44 #define DMGL_VERBOSE     (1 << 3)       /* Include implementation details.  */
  45 #define DMGL_TYPES       (1 << 4)       /* Also try to demangle type encodings.  */
  46 #define DMGL_RET_POSTFIX (1 << 5)       /* Print function return types (when
  47                                            present) after function signature.
  48                                            It applies only to the toplevel
  49                                            function type.  */
  50 #define DMGL_RET_DROP    (1 << 6)       /* Suppress printing function return
  51                                            types, even if present.  It applies
  52                                            only to the toplevel function type.
  53                                            */
  54
  55 #define DMGL_AUTO        (1 << 8)
  56 #define DMGL_GNU_V3      (1 << 14)
  57 #define DMGL_GNAT        (1 << 15)
  58 #define DMGL_DLANG       (1 << 16)
  59 #define DMGL_RUST        (1 << 17)      /* Rust wraps GNU_V3 style mangling.  */
  60
  61 /* If none of these are set, use 'current_demangling_style' as the default. */
  62 #define DMGL_STYLE_MASK (DMGL_AUTO|DMGL_GNU_V3|DMGL_JAVA|DMGL_GNAT|DMGL_DLANG|DMGL_RUST)
  63
  64 /* Disable a limit on the depth of recursion in mangled strings.
  65    Note if this limit is disabled then stack exhaustion is possible when
  66    demangling pathologically complicated strings.  Bug reports about stack
  67    exhaustion when the option is enabled will be rejected.  */
  68 #define DMGL_NO_RECURSE_LIMIT (1 << 18)
  69
  70 /* If DMGL_NO_RECURSE_LIMIT is not enabled, then this is the value used as
  71    the maximum depth of recursion allowed.  It should be enough for any
  72    real-world mangled name.  */
  73 #define DEMANGLE_RECURSION_LIMIT 2048
  74
  75 /* Enumeration of possible demangling styles.
  76
  77    Lucid and ARM styles are still kept logically distinct, even though
  78    they now both behave identically.  The resulting style is actual the
  79    union of both.  I.E. either style recognizes both "__pt__" and "__rf__"
  80    for operator "->", even though the first is lucid style and the second
  81    is ARM style. (FIXME?) */
  82
  83 extern enum demangling_styles
  84 {
  85   no_demangling = -1,
  86   unknown_demangling = 0,
  87   auto_demangling = DMGL_AUTO,
  88   gnu_v3_demangling = DMGL_GNU_V3,
  89   java_demangling = DMGL_JAVA,
  90   gnat_demangling = DMGL_GNAT,
  91   dlang_demangling = DMGL_DLANG,
  92   rust_demangling = DMGL_RUST
  93 } current_demangling_style;
  94
  95 /* Define string names for the various demangling styles. */
  96
  97 #define NO_DEMANGLING_STYLE_STRING            "none"
  98 #define AUTO_DEMANGLING_STYLE_STRING          "auto"
  99 #define GNU_V3_DEMANGLING_STYLE_STRING        "gnu-v3"
 100 #define JAVA_DEMANGLING_STYLE_STRING          "java"
 101 #define GNAT_DEMANGLING_STYLE_STRING          "gnat"
 102 #define DLANG_DEMANGLING_STYLE_STRING         "dlang"
 103 #define RUST_DEMANGLING_STYLE_STRING          "rust"
 104
 105 /* Some macros to test what demangling style is active. */
 106
 107 #define CURRENT_DEMANGLING_STYLE current_demangling_style
 108 #define AUTO_DEMANGLING (((int) CURRENT_DEMANGLING_STYLE) & DMGL_AUTO)
 109 #define GNU_V3_DEMANGLING (((int) CURRENT_DEMANGLING_STYLE) & DMGL_GNU_V3)
 110 #define JAVA_DEMANGLING (((int) CURRENT_DEMANGLING_STYLE) & DMGL_JAVA)
 111 #define GNAT_DEMANGLING (((int) CURRENT_DEMANGLING_STYLE) & DMGL_GNAT)
 112 #define DLANG_DEMANGLING (((int) CURRENT_DEMANGLING_STYLE) & DMGL_DLANG)
 113 #define RUST_DEMANGLING (((int) CURRENT_DEMANGLING_STYLE) & DMGL_RUST)
 114
 115 /* Provide information about the available demangle styles. This code is
 116    pulled from gdb into libiberty because it is useful to binutils also.  */
 117
 118 extern const struct demangler_engine
 119 {
 120   const char *const demangling_style_name;
 121   const enum demangling_styles demangling_style;
 122   const char *const demangling_style_doc;
 123 } libiberty_demanglers[];
 124
 125 extern char *
 126 cplus_demangle (const char *mangled, int options);
 127
 128 /* Note: This sets global state.  FIXME if you care about multi-threading. */
 129
 130 extern enum demangling_styles
 131 cplus_demangle_set_style (enum demangling_styles style);
 132
 133 extern enum demangling_styles
 134 cplus_demangle_name_to_style (const char *name);
 135
 136 /* Callback typedef for allocation-less demangler interfaces. */
 137 typedef void (*demangle_callbackref) (const char *, size_t, void *);
 138
 139 /* V3 ABI demangling entry points, defined in cp-demangle.c.  Callback
 140    variants return non-zero on success, zero on error.  char* variants
 141    return a string allocated by malloc on success, NULL on error.  */
 142 extern int
 143 cplus_demangle_v3_callback (const char *mangled, int options,
 144                             demangle_callbackref callback, void *opaque);
 145
 146 extern char*
 147 cplus_demangle_v3 (const char *mangled, int options);
 148
 149 extern int
 150 java_demangle_v3_callback (const char *mangled,
 151                            demangle_callbackref callback, void *opaque);
 152
 153 extern char*
 154 java_demangle_v3 (const char *mangled);
 155
 156 char *
 157 ada_demangle (const char *mangled, int options);
 158
 159 extern char *
 160 dlang_demangle (const char *mangled, int options);
 161
 162 extern int
 163 rust_demangle_callback (const char *mangled, int options,
 164                         demangle_callbackref callback, void *opaque);
 165
 166
 167 extern char *
 168 rust_demangle (const char *mangled, int options);
 169
 170 enum gnu_v3_ctor_kinds {
 171   gnu_v3_complete_object_ctor = 1,
 172   gnu_v3_base_object_ctor,
 173   gnu_v3_complete_object_allocating_ctor,
 174   /* These are not part of the V3 ABI.  Unified constructors are generated
 175      as a speed-for-space optimization when the -fdeclone-ctor-dtor option
 176      is used, and are always internal symbols.  */
 177   gnu_v3_unified_ctor,
 178   gnu_v3_object_ctor_group
 179 };
 180
 181 /* Return non-zero iff NAME is the mangled form of a constructor name
 182    in the G++ V3 ABI demangling style.  Specifically, return an `enum
 183    gnu_v3_ctor_kinds' value indicating what kind of constructor
 184    it is.  */
 185 extern enum gnu_v3_ctor_kinds
 186         is_gnu_v3_mangled_ctor (const char *name);
 187
 188
 189 enum gnu_v3_dtor_kinds {
 190   gnu_v3_deleting_dtor = 1,
 191   gnu_v3_complete_object_dtor,
 192   gnu_v3_base_object_dtor,
 193   /* These are not part of the V3 ABI.  Unified destructors are generated
 194      as a speed-for-space optimization when the -fdeclone-ctor-dtor option
 195      is used, and are always internal symbols.  */
 196   gnu_v3_unified_dtor,
 197   gnu_v3_object_dtor_group
 198 };
 199
 200 /* Return non-zero iff NAME is the mangled form of a destructor name
 201    in the G++ V3 ABI demangling style.  Specifically, return an `enum
 202    gnu_v3_dtor_kinds' value, indicating what kind of destructor
 203    it is.  */
 204 extern enum gnu_v3_dtor_kinds
 205         is_gnu_v3_mangled_dtor (const char *name);
 206
 207 /* The V3 demangler works in two passes.  The first pass builds a tree
 208    representation of the mangled name, and the second pass turns the
 209    tree representation into a demangled string.  Here we define an
 210    interface to permit a caller to build their own tree
 211    representation, which they can pass to the demangler to get a
 212    demangled string.  This can be used to canonicalize user input into
 213    something which the demangler might output.  It could also be used
 214    by other demanglers in the future.  */
 215
 216 /* These are the component types which may be found in the tree.  Many
 217    component types have one or two subtrees, referred to as left and
 218    right (a component type with only one subtree puts it in the left
 219    subtree).  */
 220
 221 enum demangle_component_type
 222 {
 223   /* A name, with a length and a pointer to a string.  */
 224   DEMANGLE_COMPONENT_NAME,
 225   /* A qualified name.  The left subtree is a class or namespace or
 226      some such thing, and the right subtree is a name qualified by
 227      that class.  */
 228   DEMANGLE_COMPONENT_QUAL_NAME,
 229   /* A local name.  The left subtree describes a function, and the
 230      right subtree is a name which is local to that function.  */
 231   DEMANGLE_COMPONENT_LOCAL_NAME,
 232   /* A typed name.  The left subtree is a name, and the right subtree
 233      describes that name as a function.  */
 234   DEMANGLE_COMPONENT_TYPED_NAME,
 235   /* A template.  The left subtree is a template name, and the right
 236      subtree is a template argument list.  */
 237   DEMANGLE_COMPONENT_TEMPLATE,
 238   /* A template parameter.  This holds a number, which is the template
 239      parameter index.  */
 240   DEMANGLE_COMPONENT_TEMPLATE_PARAM,
 241   /* A function parameter.  This holds a number, which is the index.  */
 242   DEMANGLE_COMPONENT_FUNCTION_PARAM,
 243   /* A constructor.  This holds a name and the kind of
 244      constructor.  */
 245   DEMANGLE_COMPONENT_CTOR,
 246   /* A destructor.  This holds a name and the kind of destructor.  */
 247   DEMANGLE_COMPONENT_DTOR,
 248   /* A vtable.  This has one subtree, the type for which this is a
 249      vtable.  */
 250   DEMANGLE_COMPONENT_VTABLE,
 251   /* A VTT structure.  This has one subtree, the type for which this
 252      is a VTT.  */
 253   DEMANGLE_COMPONENT_VTT,
 254   /* A construction vtable.  The left subtree is the type for which
 255      this is a vtable, and the right subtree is the derived type for
 256      which this vtable is built.  */
 257   DEMANGLE_COMPONENT_CONSTRUCTION_VTABLE,
 258   /* A typeinfo structure.  This has one subtree, the type for which
 259      this is the tpeinfo structure.  */
 260   DEMANGLE_COMPONENT_TYPEINFO,
 261   /* A typeinfo name.  This has one subtree, the type for which this
 262      is the typeinfo name.  */
 263   DEMANGLE_COMPONENT_TYPEINFO_NAME,
 264   /* A typeinfo function.  This has one subtree, the type for which
 265      this is the tpyeinfo function.  */
 266   DEMANGLE_COMPONENT_TYPEINFO_FN,
 267   /* A thunk.  This has one subtree, the name for which this is a
 268      thunk.  */
 269   DEMANGLE_COMPONENT_THUNK,
 270   /* A virtual thunk.  This has one subtree, the name for which this
 271      is a virtual thunk.  */
 272   DEMANGLE_COMPONENT_VIRTUAL_THUNK,
 273   /* A covariant thunk.  This has one subtree, the name for which this
 274      is a covariant thunk.  */
 275   DEMANGLE_COMPONENT_COVARIANT_THUNK,
 276   /* A Java class.  This has one subtree, the type.  */
 277   DEMANGLE_COMPONENT_JAVA_CLASS,
 278   /* A guard variable.  This has one subtree, the name for which this
 279      is a guard variable.  */
 280   DEMANGLE_COMPONENT_GUARD,
 281   /* The init and wrapper functions for C++11 thread_local variables.  */
 282   DEMANGLE_COMPONENT_TLS_INIT,
 283   DEMANGLE_COMPONENT_TLS_WRAPPER,
 284   /* A reference temporary.  This has one subtree, the name for which
 285      this is a temporary.  */
 286   DEMANGLE_COMPONENT_REFTEMP,
 287   /* A hidden alias.  This has one subtree, the encoding for which it
 288      is providing alternative linkage.  */
 289   DEMANGLE_COMPONENT_HIDDEN_ALIAS,
 290   /* A standard substitution.  This holds the name of the
 291      substitution.  */
 292   DEMANGLE_COMPONENT_SUB_STD,
 293   /* The restrict qualifier.  The one subtree is the type which is
 294      being qualified.  */
 295   DEMANGLE_COMPONENT_RESTRICT,
 296   /* The volatile qualifier.  The one subtree is the type which is
 297      being qualified.  */
 298   DEMANGLE_COMPONENT_VOLATILE,
 299   /* The const qualifier.  The one subtree is the type which is being
 300      qualified.  */
 301   DEMANGLE_COMPONENT_CONST,
 302   /* The restrict qualifier modifying a member function.  The one
 303      subtree is the type which is being qualified.  */
 304   DEMANGLE_COMPONENT_RESTRICT_THIS,
 305   /* The volatile qualifier modifying a member function.  The one
 306      subtree is the type which is being qualified.  */
 307   DEMANGLE_COMPONENT_VOLATILE_THIS,
 308   /* The const qualifier modifying a member function.  The one subtree
 309      is the type which is being qualified.  */
 310   DEMANGLE_COMPONENT_CONST_THIS,
 311   /* C++11 A reference modifying a member function.  The one subtree is the
 312      type which is being referenced.  */
 313   DEMANGLE_COMPONENT_REFERENCE_THIS,
 314   /* C++11: An rvalue reference modifying a member function.  The one
 315      subtree is the type which is being referenced.  */
 316   DEMANGLE_COMPONENT_RVALUE_REFERENCE_THIS,
 317   /* A vendor qualifier.  The left subtree is the type which is being
 318      qualified, and the right subtree is the name of the
 319      qualifier.  */
 320   DEMANGLE_COMPONENT_VENDOR_TYPE_QUAL,
 321   /* A pointer.  The one subtree is the type which is being pointed
 322      to.  */
 323   DEMANGLE_COMPONENT_POINTER,
 324   /* A reference.  The one subtree is the type which is being
 325      referenced.  */
 326   DEMANGLE_COMPONENT_REFERENCE,
 327   /* C++0x: An rvalue reference.  The one subtree is the type which is
 328      being referenced.  */
 329   DEMANGLE_COMPONENT_RVALUE_REFERENCE,
 330   /* A complex type.  The one subtree is the base type.  */
 331   DEMANGLE_COMPONENT_COMPLEX,
 332   /* An imaginary type.  The one subtree is the base type.  */
 333   DEMANGLE_COMPONENT_IMAGINARY,
 334   /* A builtin type.  This holds the builtin type information.  */
 335   DEMANGLE_COMPONENT_BUILTIN_TYPE,
 336   /* A vendor's builtin type.  This holds the name of the type.  */
 337   DEMANGLE_COMPONENT_VENDOR_TYPE,
 338   /* A function type.  The left subtree is the return type.  The right
 339      subtree is a list of ARGLIST nodes.  Either or both may be
 340      NULL.  */
 341   DEMANGLE_COMPONENT_FUNCTION_TYPE,
 342   /* An array type.  The left subtree is the dimension, which may be
 343      NULL, or a string (represented as DEMANGLE_COMPONENT_NAME), or an
 344      expression.  The right subtree is the element type.  */
 345   DEMANGLE_COMPONENT_ARRAY_TYPE,
 346   /* A pointer to member type.  The left subtree is the class type,
 347      and the right subtree is the member type.  CV-qualifiers appear
 348      on the latter.  */
 349   DEMANGLE_COMPONENT_PTRMEM_TYPE,
 350   /* A fixed-point type.  */
 351   DEMANGLE_COMPONENT_FIXED_TYPE,
 352   /* A vector type.  The left subtree is the number of elements,
 353      the right subtree is the element type.  */
 354   DEMANGLE_COMPONENT_VECTOR_TYPE,
 355   /* An argument list.  The left subtree is the current argument, and
 356      the right subtree is either NULL or another ARGLIST node.  */
 357   DEMANGLE_COMPONENT_ARGLIST,
 358   /* A template argument list.  The left subtree is the current
 359      template argument, and the right subtree is either NULL or
 360      another TEMPLATE_ARGLIST node.  */
 361   DEMANGLE_COMPONENT_TEMPLATE_ARGLIST,
 362   /* A template parameter object (C++20).  The left subtree is the
 363      corresponding template argument.  */
 364   DEMANGLE_COMPONENT_TPARM_OBJ,
 365   /* An initializer list.  The left subtree is either an explicit type or
 366      NULL, and the right subtree is a DEMANGLE_COMPONENT_ARGLIST.  */
 367   DEMANGLE_COMPONENT_INITIALIZER_LIST,
 368   /* An operator.  This holds information about a standard
 369      operator.  */
 370   DEMANGLE_COMPONENT_OPERATOR,
 371   /* An extended operator.  This holds the number of arguments, and
 372      the name of the extended operator.  */
 373   DEMANGLE_COMPONENT_EXTENDED_OPERATOR,
 374   /* A typecast, represented as a unary operator.  The one subtree is
 375      the type to which the argument should be cast.  */
 376   DEMANGLE_COMPONENT_CAST,
 377   /* A conversion operator, represented as a unary operator.  The one
 378      subtree is the type to which the argument should be converted
 379      to.  */
 380   DEMANGLE_COMPONENT_CONVERSION,
 381   /* A nullary expression.  The left subtree is the operator.  */
 382   DEMANGLE_COMPONENT_NULLARY,
 383   /* A unary expression.  The left subtree is the operator, and the
 384      right subtree is the single argument.  */
 385   DEMANGLE_COMPONENT_UNARY,
 386   /* A binary expression.  The left subtree is the operator, and the
 387      right subtree is a BINARY_ARGS.  */
 388   DEMANGLE_COMPONENT_BINARY,
 389   /* Arguments to a binary expression.  The left subtree is the first
 390      argument, and the right subtree is the second argument.  */
 391   DEMANGLE_COMPONENT_BINARY_ARGS,
 392   /* A trinary expression.  The left subtree is the operator, and the
 393      right subtree is a TRINARY_ARG1.  */
 394   DEMANGLE_COMPONENT_TRINARY,
 395   /* Arguments to a trinary expression.  The left subtree is the first
 396      argument, and the right subtree is a TRINARY_ARG2.  */
 397   DEMANGLE_COMPONENT_TRINARY_ARG1,
 398   /* More arguments to a trinary expression.  The left subtree is the
 399      second argument, and the right subtree is the third argument.  */
 400   DEMANGLE_COMPONENT_TRINARY_ARG2,
 401   /* A literal.  The left subtree is the type, and the right subtree
 402      is the value, represented as a DEMANGLE_COMPONENT_NAME.  */
 403   DEMANGLE_COMPONENT_LITERAL,
 404   /* A negative literal.  Like LITERAL, but the value is negated.
 405      This is a minor hack: the NAME used for LITERAL points directly
 406      to the mangled string, but since negative numbers are mangled
 407      using 'n' instead of '-', we want a way to indicate a negative
 408      number which involves neither modifying the mangled string nor
 409      allocating a new copy of the literal in memory.  */
 410   DEMANGLE_COMPONENT_LITERAL_NEG,
 411   /* A vendor's builtin expression.  The left subtree holds the
 412      expression's name, and the right subtree is a argument list.  */
 413   DEMANGLE_COMPONENT_VENDOR_EXPR,
 414   /* A libgcj compiled resource.  The left subtree is the name of the
 415      resource.  */
 416   DEMANGLE_COMPONENT_JAVA_RESOURCE,
 417   /* A name formed by the concatenation of two parts.  The left
 418      subtree is the first part and the right subtree the second.  */
 419   DEMANGLE_COMPONENT_COMPOUND_NAME,
 420   /* A name formed by a single character.  */
 421   DEMANGLE_COMPONENT_CHARACTER,
 422   /* A number.  */
 423   DEMANGLE_COMPONENT_NUMBER,
 424   /* A decltype type.  */
 425   DEMANGLE_COMPONENT_DECLTYPE,
 426   /* Global constructors keyed to name.  */
 427   DEMANGLE_COMPONENT_GLOBAL_CONSTRUCTORS,
 428   /* Global destructors keyed to name.  */
 429   DEMANGLE_COMPONENT_GLOBAL_DESTRUCTORS,
 430   /* A lambda closure type.  */
 431   DEMANGLE_COMPONENT_LAMBDA,
 432   /* A default argument scope.  */
 433   DEMANGLE_COMPONENT_DEFAULT_ARG,
 434   /* An unnamed type.  */
 435   DEMANGLE_COMPONENT_UNNAMED_TYPE,
 436   /* A transactional clone.  This has one subtree, the encoding for
 437      which it is providing alternative linkage.  */
 438   DEMANGLE_COMPONENT_TRANSACTION_CLONE,
 439   /* A non-transactional clone entry point.  In the i386/x86_64 abi,
 440      the unmangled symbol of a tm_callable becomes a thunk and the
 441      non-transactional function version is mangled thus.  */
 442   DEMANGLE_COMPONENT_NONTRANSACTION_CLONE,
 443   /* A pack expansion.  */
 444   DEMANGLE_COMPONENT_PACK_EXPANSION,
 445   /* A name with an ABI tag.  */
 446   DEMANGLE_COMPONENT_TAGGED_NAME,
 447   /* A transaction-safe function type.  */
 448   DEMANGLE_COMPONENT_TRANSACTION_SAFE,
 449   /* A cloned function.  */
 450   DEMANGLE_COMPONENT_CLONE,
 451   DEMANGLE_COMPONENT_NOEXCEPT,
 452   DEMANGLE_COMPONENT_THROW_SPEC,
 453
 454   DEMANGLE_COMPONENT_STRUCTURED_BINDING,
 455
 456   DEMANGLE_COMPONENT_MODULE_NAME,
 457   DEMANGLE_COMPONENT_MODULE_PARTITION,
 458   DEMANGLE_COMPONENT_MODULE_ENTITY,
 459   DEMANGLE_COMPONENT_MODULE_INIT,
 460
 461   DEMANGLE_COMPONENT_TEMPLATE_HEAD,
 462   DEMANGLE_COMPONENT_TEMPLATE_TYPE_PARM,
 463   DEMANGLE_COMPONENT_TEMPLATE_NON_TYPE_PARM,
 464   DEMANGLE_COMPONENT_TEMPLATE_TEMPLATE_PARM,
 465   DEMANGLE_COMPONENT_TEMPLATE_PACK_PARM,
 466
 467   /* A builtin type with argument.  This holds the builtin type
 468      information.  */
 469   DEMANGLE_COMPONENT_EXTENDED_BUILTIN_TYPE
 470
 471 };
 472
 473 /* Types which are only used internally.  */
 474
 475 struct demangle_operator_info;
 476 struct demangle_builtin_type_info;
 477
 478 /* A node in the tree representation is an instance of a struct
 479    demangle_component.  Note that the field names of the struct are
 480    not well protected against macros defined by the file including
 481    this one.  We can fix this if it ever becomes a problem.  */
 482
 483 struct demangle_component
 484 {
 485   /* The type of this component.  */
 486   enum demangle_component_type type;
 487
 488   /* Guard against recursive component printing.
 489      Initialize to zero.  Private to d_print_comp.
 490      All other fields are final after initialization.  */
 491   int d_printing;
 492   int d_counting;
 493
 494   union
 495   {
 496     /* For DEMANGLE_COMPONENT_NAME.  */
 497     struct
 498     {
 499       /* A pointer to the name (which need not NULL terminated) and
 500          its length.  */
 501       const char *s;
 502       int len;
 503     } s_name;
 504
 505     /* For DEMANGLE_COMPONENT_OPERATOR.  */
 506     struct
 507     {
 508       /* Operator.  */
 509       const struct demangle_operator_info *op;
 510     } s_operator;
 511
 512     /* For DEMANGLE_COMPONENT_EXTENDED_OPERATOR.  */
 513     struct
 514     {
 515       /* Number of arguments.  */
 516       int args;
 517       /* Name.  */
 518       struct demangle_component *name;
 519     } s_extended_operator;
 520
 521     /* For DEMANGLE_COMPONENT_FIXED_TYPE.  */
 522     struct
 523     {
 524       /* The length, indicated by a C integer type name.  */
 525       struct demangle_component *length;
 526       /* _Accum or _Fract?  */
 527       short accum;
 528       /* Saturating or not?  */
 529       short sat;
 530     } s_fixed;
 531
 532     /* For DEMANGLE_COMPONENT_CTOR.  */
 533     struct
 534     {
 535       /* Kind of constructor.  */
 536       enum gnu_v3_ctor_kinds kind;
 537       /* Name.  */
 538       struct demangle_component *name;
 539     } s_ctor;
 540
 541     /* For DEMANGLE_COMPONENT_DTOR.  */
 542     struct
 543     {
 544       /* Kind of destructor.  */
 545       enum gnu_v3_dtor_kinds kind;
 546       /* Name.  */
 547       struct demangle_component *name;
 548     } s_dtor;
 549
 550     /* For DEMANGLE_COMPONENT_BUILTIN_TYPE.  */
 551     struct
 552     {
 553       /* Builtin type.  */
 554       const struct demangle_builtin_type_info *type;
 555     } s_builtin;
 556
 557     /* For DEMANGLE_COMPONENT_EXTENDED_BUILTIN_TYPE.  */
 558     struct
 559     {
 560       /* Builtin type.  */
 561       const struct demangle_builtin_type_info *type;
 562       short arg;
 563       char suffix;
 564     } s_extended_builtin;
 565
 566     /* For DEMANGLE_COMPONENT_SUB_STD.  */
 567     struct
 568     {
 569       /* Standard substitution string.  */
 570       const char* string;
 571       /* Length of string.  */
 572       int len;
 573     } s_string;
 574
 575     /* For DEMANGLE_COMPONENT_*_PARAM.  */
 576     struct
 577     {
 578       /* Parameter index.  */
 579       long number;
 580     } s_number;
 581
 582     /* For DEMANGLE_COMPONENT_CHARACTER.  */
 583     struct
 584     {
 585       int character;
 586     } s_character;
 587
 588     /* For other types.  */
 589     struct
 590     {
 591       /* Left (or only) subtree.  */
 592       struct demangle_component *left;
 593       /* Right subtree.  */
 594       struct demangle_component *right;
 595     } s_binary;
 596
 597     struct
 598     {
 599       /* subtree, same place as d_left.  */
 600       struct demangle_component *sub;
 601       /* integer.  */
 602       int num;
 603     } s_unary_num;
 604
 605   } u;
 606 };
 607
 608 /* People building mangled trees are expected to allocate instances of
 609    struct demangle_component themselves.  They can then call one of
 610    the following functions to fill them in.  */
 611
 612 /* Fill in most component types with a left subtree and a right
 613    subtree.  Returns non-zero on success, zero on failure, such as an
 614    unrecognized or inappropriate component type.  */
 615
 616 extern int
 617 cplus_demangle_fill_component (struct demangle_component *fill,
 618                                enum demangle_component_type,
 619                                struct demangle_component *left,
 620                                struct demangle_component *right);
 621
 622 /* Fill in a DEMANGLE_COMPONENT_NAME.  Returns non-zero on success,
 623    zero for bad arguments.  */
 624
 625 extern int
 626 cplus_demangle_fill_name (struct demangle_component *fill,
 627                           const char *, int);
 628
 629 /* Fill in a DEMANGLE_COMPONENT_BUILTIN_TYPE, using the name of the
 630    builtin type (e.g., "int", etc.).  Returns non-zero on success,
 631    zero if the type is not recognized.  */
 632
 633 extern int
 634 cplus_demangle_fill_builtin_type (struct demangle_component *fill,
 635                                   const char *type_name);
 636
 637 /* Fill in a DEMANGLE_COMPONENT_OPERATOR, using the name of the
 638    operator and the number of arguments which it takes (the latter is
 639    used to disambiguate operators which can be both binary and unary,
 640    such as '-').  Returns non-zero on success, zero if the operator is
 641    not recognized.  */
 642
 643 extern int
 644 cplus_demangle_fill_operator (struct demangle_component *fill,
 645                               const char *opname, int args);
 646
 647 /* Fill in a DEMANGLE_COMPONENT_EXTENDED_OPERATOR, providing the
 648    number of arguments and the name.  Returns non-zero on success,
 649    zero for bad arguments.  */
 650
 651 extern int
 652 cplus_demangle_fill_extended_operator (struct demangle_component *fill,
 653                                        int numargs,
 654                                        struct demangle_component *nm);
 655
 656 /* Fill in a DEMANGLE_COMPONENT_CTOR.  Returns non-zero on success,
 657    zero for bad arguments.  */
 658
 659 extern int
 660 cplus_demangle_fill_ctor (struct demangle_component *fill,
 661                           enum gnu_v3_ctor_kinds kind,
 662                           struct demangle_component *name);
 663
 664 /* Fill in a DEMANGLE_COMPONENT_DTOR.  Returns non-zero on success,
 665    zero for bad arguments.  */
 666
 667 extern int
 668 cplus_demangle_fill_dtor (struct demangle_component *fill,
 669                           enum gnu_v3_dtor_kinds kind,
 670                           struct demangle_component *name);
 671
 672 /* This function translates a mangled name into a struct
 673    demangle_component tree.  The first argument is the mangled name.
 674    The second argument is DMGL_* options.  This returns a pointer to a
 675    tree on success, or NULL on failure.  On success, the third
 676    argument is set to a block of memory allocated by malloc.  This
 677    block should be passed to free when the tree is no longer
 678    needed.  */
 679
 680 extern struct demangle_component *
 681 cplus_demangle_v3_components (const char *mangled, int options, void **mem);
 682
 683 /* This function takes a struct demangle_component tree and returns
 684    the corresponding demangled string.  The first argument is DMGL_*
 685    options.  The second is the tree to demangle.  The third is a guess
 686    at the length of the demangled string, used to initially allocate
 687    the return buffer.  The fourth is a pointer to a size_t.  On
 688    success, this function returns a buffer allocated by malloc(), and
 689    sets the size_t pointed to by the fourth argument to the size of
 690    the allocated buffer (not the length of the returned string).  On
 691    failure, this function returns NULL, and sets the size_t pointed to
 692    by the fourth argument to 0 for an invalid tree, or to 1 for a
 693    memory allocation error.  */
 694
 695 extern char *
 696 cplus_demangle_print (int options,
 697                       struct demangle_component *tree,
 698                       int estimated_length,
 699                       size_t *p_allocated_size);
 700
 701 /* This function takes a struct demangle_component tree and passes back
 702    a demangled string in one or more calls to a callback function.
 703    The first argument is DMGL_* options.  The second is the tree to
 704    demangle.  The third is a pointer to a callback function; on each call
 705    this receives an element of the demangled string, its length, and an
 706    opaque value.  The fourth is the opaque value passed to the callback.
 707    The callback is called once or more to return the full demangled
 708    string.  The demangled element string is always nul-terminated, though
 709    its length is also provided for convenience.  In contrast to
 710    cplus_demangle_print(), this function does not allocate heap memory
 711    to grow output strings (except perhaps where alloca() is implemented
 712    by malloc()), and so is normally safe for use where the heap has been
 713    corrupted.  On success, this function returns 1; on failure, 0.  */
 714
 715 extern int
 716 cplus_demangle_print_callback (int options,
 717                                struct demangle_component *tree,
 718                                demangle_callbackref callback, void *opaque);
 719
 720 #ifdef __cplusplus
 721 }
 722 #endif /* __cplusplus */
 723
 724 #endif  /* DEMANGLE_H */