gdb/parser-defs.h

   1 /* Parser definitions for GDB.
   2
   3    Copyright (C) 1986-2014 Free Software Foundation, Inc.
   4
   5    Modified from expread.y by the Department of Computer Science at the
   6    State University of New York at Buffalo.
   7
   8    This file is part of GDB.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  22
  23 #if !defined (PARSER_DEFS_H)
  24 #define PARSER_DEFS_H 1
  25
  26 #include "doublest.h"
  27 #include "vec.h"
  28 #include "expression.h"
  29
  30 struct block;
  31 struct language_defn;
  32 struct internalvar;
  33
  34 extern int parser_debug;
  35
  36 #define parse_gdbarch(ps) ((ps)->expout->gdbarch)
  37 #define parse_language(ps) ((ps)->expout->language_defn)
  38
  39 struct parser_state
  40 {
  41   /* The expression related to this parser state.  */
  42
  43   struct expression *expout;
  44
  45   /* The size of the expression above.  */
  46
  47   size_t expout_size;
  48
  49   /* The number of elements already in the expression.  This is used
  50      to know where to put new elements.  */
  51
  52   size_t expout_ptr;
  53 };
  54
  55 /* If this is nonzero, this block is used as the lexical context
  56    for symbol names.  */
  57
  58 extern const struct block *expression_context_block;
  59
  60 /* If expression_context_block is non-zero, then this is the PC within
  61    the block that we want to evaluate expressions at.  When debugging
  62    C or C++ code, we use this to find the exact line we're at, and
  63    then look up the macro definitions active at that point.  */
  64 extern CORE_ADDR expression_context_pc;
  65
  66 /* The innermost context required by the stack and register variables
  67    we've encountered so far.  */
  68 extern const struct block *innermost_block;
  69
  70 /* The block in which the most recently discovered symbol was found.
  71    FIXME: Should be declared along with lookup_symbol in symtab.h; is not
  72    related specifically to parsing.  */
  73 extern const struct block *block_found;
  74
  75 /* Number of arguments seen so far in innermost function call.  */
  76 extern int arglist_len;
  77
  78 /* A string token, either a char-string or bit-string.  Char-strings are
  79    used, for example, for the names of symbols.  */
  80
  81 struct stoken
  82   {
  83     /* Pointer to first byte of char-string or first bit of bit-string.  */
  84     const char *ptr;
  85     /* Length of string in bytes for char-string or bits for bit-string.  */
  86     int length;
  87   };
  88
  89 struct typed_stoken
  90   {
  91     /* A language-specific type field.  */
  92     int type;
  93     /* Pointer to first byte of char-string or first bit of bit-string.  */
  94     char *ptr;
  95     /* Length of string in bytes for char-string or bits for bit-string.  */
  96     int length;
  97   };
  98
  99 struct stoken_vector
 100   {
 101     int len;
 102     struct typed_stoken *tokens;
 103   };
 104
 105 struct ttype
 106   {
 107     struct stoken stoken;
 108     struct type *type;
 109   };
 110
 111 struct symtoken
 112   {
 113     struct stoken stoken;
 114     struct symbol *sym;
 115     int is_a_field_of_this;
 116   };
 117
 118 struct objc_class_str
 119   {
 120     struct stoken stoken;
 121     struct type *type;
 122     int class;
 123   };
 124
 125 typedef struct type *type_ptr;
 126 DEF_VEC_P (type_ptr);
 127
 128 /* For parsing of complicated types.
 129    An array should be preceded in the list by the size of the array.  */
 130 enum type_pieces
 131   {
 132     tp_end = -1,
 133     tp_pointer,
 134     tp_reference,
 135     tp_array,
 136     tp_function,
 137     tp_function_with_arguments,
 138     tp_const,
 139     tp_volatile,
 140     tp_space_identifier,
 141     tp_type_stack
 142   };
 143 /* The stack can contain either an enum type_pieces or an int.  */
 144 union type_stack_elt
 145   {
 146     enum type_pieces piece;
 147     int int_val;
 148     struct type_stack *stack_val;
 149     VEC (type_ptr) *typelist_val;
 150   };
 151
 152 /* The type stack is an instance of this structure.  */
 153
 154 struct type_stack
 155 {
 156   /* Elements on the stack.  */
 157   union type_stack_elt *elements;
 158   /* Current stack depth.  */
 159   int depth;
 160   /* Allocated size of stack.  */
 161   int size;
 162 };
 163
 164 /* Helper function to initialize the expout, expout_size, expout_ptr
 165    trio inside PS before it is used to store expression elements created
 166    during the parsing of an expression.  INITIAL_SIZE is the initial size of
 167    the expout array.  LANG is the language used to parse the expression.
 168    And GDBARCH is the gdbarch to use during parsing.  */
 169
 170 extern void initialize_expout (struct parser_state *ps,
 171                                size_t initial_size,
 172                                const struct language_defn *lang,
 173                                struct gdbarch *gdbarch);
 174
 175 /* Helper function that reallocates the EXPOUT inside PS in order to
 176    eliminate any unused space.  It is generally used when the expression
 177    has just been parsed and created.  */
 178
 179 extern void reallocate_expout (struct parser_state *ps);
 180
 181 /* Reverse an expression from suffix form (in which it is constructed)
 182    to prefix form (in which we can conveniently print or execute it).
 183    Ordinarily this always returns -1.  However, if EXPOUT_LAST_STRUCT
 184    is not -1 (i.e., we are trying to complete a field name), it will
 185    return the index of the subexpression which is the left-hand-side
 186    of the struct operation at EXPOUT_LAST_STRUCT.  */
 187
 188 extern int prefixify_expression (struct expression *expr);
 189
 190 extern void write_exp_elt_opcode (struct parser_state *, enum exp_opcode);
 191
 192 extern void write_exp_elt_sym (struct parser_state *, struct symbol *);
 193
 194 extern void write_exp_elt_longcst (struct parser_state *, LONGEST);
 195
 196 extern void write_exp_elt_dblcst (struct parser_state *, DOUBLEST);
 197
 198 extern void write_exp_elt_decfloatcst (struct parser_state *, gdb_byte *);
 199
 200 extern void write_exp_elt_type (struct parser_state *, struct type *);
 201
 202 extern void write_exp_elt_intern (struct parser_state *, struct internalvar *);
 203
 204 extern void write_exp_string (struct parser_state *, struct stoken);
 205
 206 void write_exp_string_vector (struct parser_state *, int type,
 207                               struct stoken_vector *vec);
 208
 209 extern void write_exp_bitstring (struct parser_state *, struct stoken);
 210
 211 extern void write_exp_elt_block (struct parser_state *, const struct block *);
 212
 213 extern void write_exp_elt_objfile (struct parser_state *,
 214                                    struct objfile *objfile);
 215
 216 extern void write_exp_msymbol (struct parser_state *,
 217                                struct bound_minimal_symbol);
 218
 219 extern void write_dollar_variable (struct parser_state *, struct stoken str);
 220
 221 extern void mark_struct_expression (struct parser_state *);
 222
 223 extern const char *find_template_name_end (const char *);
 224
 225 extern void start_arglist (void);
 226
 227 extern int end_arglist (void);
 228
 229 extern char *copy_name (struct stoken);
 230
 231 extern void insert_type (enum type_pieces);
 232
 233 extern void push_type (enum type_pieces);
 234
 235 extern void push_type_int (int);
 236
 237 extern void insert_type_address_space (struct parser_state *, char *);
 238
 239 extern enum type_pieces pop_type (void);
 240
 241 extern int pop_type_int (void);
 242
 243 extern struct type_stack *get_type_stack (void);
 244
 245 extern struct type_stack *append_type_stack (struct type_stack *to,
 246                                              struct type_stack *from);
 247
 248 extern void push_type_stack (struct type_stack *stack);
 249
 250 extern void type_stack_cleanup (void *arg);
 251
 252 extern void push_typelist (VEC (type_ptr) *typelist);
 253
 254 extern int length_of_subexp (struct expression *, int);
 255
 256 extern int dump_subexp (struct expression *, struct ui_file *, int);
 257
 258 extern int dump_subexp_body_standard (struct expression *,
 259                                       struct ui_file *, int);
 260
 261 extern void operator_length (const struct expression *, int, int *, int *);
 262
 263 extern void operator_length_standard (const struct expression *, int, int *,
 264                                       int *);
 265
 266 extern int operator_check_standard (struct expression *exp, int pos,
 267                                     int (*objfile_func)
 268                                       (struct objfile *objfile, void *data),
 269                                     void *data);
 270
 271 extern char *op_name_standard (enum exp_opcode);
 272
 273 extern struct type *follow_types (struct type *);
 274
 275 extern void null_post_parser (struct expression **, int);
 276
 277 extern int parse_float (const char *p, int len, DOUBLEST *d,
 278                         const char **suffix);
 279
 280 extern int parse_c_float (struct gdbarch *gdbarch, const char *p, int len,
 281                           DOUBLEST *d, struct type **t);
 282
 283 /* During parsing of a C expression, the pointer to the next character
 284    is in this variable.  */
 285
 286 extern const char *lexptr;
 287
 288 /* After a token has been recognized, this variable points to it.
 289    Currently used only for error reporting.  */
 290 extern const char *prev_lexptr;
 291
 292 /* Current depth in parentheses within the expression.  */
 293
 294 extern int paren_depth;
 295
 296 /* Nonzero means stop parsing on first comma (if not within parentheses).  */
 297
 298 extern int comma_terminates;
 299 \f
 300 /* These codes indicate operator precedences for expression printing,
 301    least tightly binding first.  */
 302 /* Adding 1 to a precedence value is done for binary operators,
 303    on the operand which is more tightly bound, so that operators
 304    of equal precedence within that operand will get parentheses.  */
 305 /* PREC_HYPER and PREC_ABOVE_COMMA are not the precedence of any operator;
 306    they are used as the "surrounding precedence" to force
 307    various kinds of things to be parenthesized.  */
 308 enum precedence
 309   {
 310     PREC_NULL, PREC_COMMA, PREC_ABOVE_COMMA, PREC_ASSIGN, PREC_LOGICAL_OR,
 311     PREC_LOGICAL_AND, PREC_BITWISE_IOR, PREC_BITWISE_AND, PREC_BITWISE_XOR,
 312     PREC_EQUAL, PREC_ORDER, PREC_SHIFT, PREC_ADD, PREC_MUL, PREC_REPEAT,
 313     PREC_HYPER, PREC_PREFIX, PREC_SUFFIX, PREC_BUILTIN_FUNCTION
 314   };
 315
 316 /* Table mapping opcodes into strings for printing operators
 317    and precedences of the operators.  */
 318
 319 struct op_print
 320   {
 321     char *string;
 322     enum exp_opcode opcode;
 323     /* Precedence of operator.  These values are used only by comparisons.  */
 324     enum precedence precedence;
 325
 326     /* For a binary operator:  1 iff right associate.
 327        For a unary operator:  1 iff postfix.  */
 328     int right_assoc;
 329   };
 330
 331 /* Information needed to print, prefixify, and evaluate expressions for
 332    a given language.  */
 333
 334 struct exp_descriptor
 335   {
 336     /* Print subexpression.  */
 337     void (*print_subexp) (struct expression *, int *, struct ui_file *,
 338                           enum precedence);
 339
 340     /* Returns number of exp_elements needed to represent an operator and
 341        the number of subexpressions it takes.  */
 342     void (*operator_length) (const struct expression*, int, int*, int *);
 343
 344     /* Call TYPE_FUNC and OBJFILE_FUNC for any TYPE and OBJFILE found being
 345        referenced by the single operator of EXP at position POS.  Operator
 346        parameters are located at positive (POS + number) offsets in EXP.
 347        The functions should never be called with NULL TYPE or NULL OBJFILE.
 348        Functions should get passed an arbitrary caller supplied DATA pointer.
 349        If any of the functions returns non-zero value then (any other) non-zero
 350        value should be immediately returned to the caller.  Otherwise zero
 351        should be returned.  */
 352     int (*operator_check) (struct expression *exp, int pos,
 353                            int (*objfile_func) (struct objfile *objfile,
 354                                                 void *data),
 355                            void *data);
 356
 357     /* Name of this operator for dumping purposes.
 358        The returned value should never be NULL, even if EXP_OPCODE is
 359        an unknown opcode (a string containing an image of the numeric
 360        value of the opcode can be returned, for instance).  */
 361     char *(*op_name) (enum exp_opcode);
 362
 363     /* Dump the rest of this (prefix) expression after the operator
 364        itself has been printed.  See dump_subexp_body_standard in
 365        (expprint.c).  */
 366     int (*dump_subexp_body) (struct expression *, struct ui_file *, int);
 367
 368     /* Evaluate an expression.  */
 369     struct value *(*evaluate_exp) (struct type *, struct expression *,
 370                                    int *, enum noside);
 371   };
 372
 373
 374 /* Default descriptor containing standard definitions of all
 375    elements.  */
 376 extern const struct exp_descriptor exp_descriptor_standard;
 377
 378 /* Functions used by language-specific extended operators to (recursively)
 379    print/dump subexpressions.  */
 380
 381 extern void print_subexp (struct expression *, int *, struct ui_file *,
 382                           enum precedence);
 383
 384 extern void print_subexp_standard (struct expression *, int *,
 385                                    struct ui_file *, enum precedence);
 386
 387 /* Function used to avoid direct calls to fprintf
 388    in the code generated by the bison parser.  */
 389
 390 extern void parser_fprintf (FILE *, const char *, ...) ATTRIBUTE_PRINTF (2, 3);
 391
 392 extern int exp_uses_objfile (struct expression *exp, struct objfile *objfile);
 393
 394 extern void mark_completion_tag (enum type_code, const char *ptr,
 395                                  int length);
 396
 397 /* Reallocate the `expout' pointer inside PS so that it can accommodate
 398    at least LENELT expression elements.  This function does nothing if
 399    there is enough room for the elements.  */
 400
 401 extern void increase_expout_size (struct parser_state *ps, size_t lenelt);
 402
 403 #endif /* PARSER_DEFS_H */
 404