gdb/parser-defs.h

   1 /* Parser definitions for GDB.
   2
   3    Copyright (C) 1986, 1989-2000, 2002, 2007-2012 Free Software
   4    Foundation, Inc.
   5
   6    Modified from expread.y by the Department of Computer Science at the
   7    State University of New York at Buffalo.
   8
   9    This file is part of GDB.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  23
  24 #if !defined (PARSER_DEFS_H)
  25 #define PARSER_DEFS_H 1
  26
  27 #include "doublest.h"
  28
  29 struct block;
  30
  31 extern int parser_debug;
  32
  33 extern struct expression *expout;
  34 extern int expout_size;
  35 extern int expout_ptr;
  36
  37 #define parse_gdbarch (expout->gdbarch)
  38 #define parse_language (expout->language_defn)
  39
  40 /* If this is nonzero, this block is used as the lexical context
  41    for symbol names.  */
  42
  43 extern struct block *expression_context_block;
  44
  45 /* If expression_context_block is non-zero, then this is the PC within
  46    the block that we want to evaluate expressions at.  When debugging
  47    C or C++ code, we use this to find the exact line we're at, and
  48    then look up the macro definitions active at that point.  */
  49 extern CORE_ADDR expression_context_pc;
  50
  51 /* The innermost context required by the stack and register variables
  52    we've encountered so far.  */
  53 extern struct block *innermost_block;
  54
  55 /* The block in which the most recently discovered symbol was found.
  56    FIXME: Should be declared along with lookup_symbol in symtab.h; is not
  57    related specifically to parsing.  */
  58 extern struct block *block_found;
  59
  60 /* Number of arguments seen so far in innermost function call.  */
  61 extern int arglist_len;
  62
  63 /* A string token, either a char-string or bit-string.  Char-strings are
  64    used, for example, for the names of symbols.  */
  65
  66 struct stoken
  67   {
  68     /* Pointer to first byte of char-string or first bit of bit-string.  */
  69     char *ptr;
  70     /* Length of string in bytes for char-string or bits for bit-string.  */
  71     int length;
  72   };
  73
  74 struct typed_stoken
  75   {
  76     /* A language-specific type field.  */
  77     int type;
  78     /* Pointer to first byte of char-string or first bit of bit-string.  */
  79     char *ptr;
  80     /* Length of string in bytes for char-string or bits for bit-string.  */
  81     int length;
  82   };
  83
  84 struct stoken_vector
  85   {
  86     int len;
  87     struct typed_stoken *tokens;
  88   };
  89
  90 struct ttype
  91   {
  92     struct stoken stoken;
  93     struct type *type;
  94   };
  95
  96 struct symtoken
  97   {
  98     struct stoken stoken;
  99     struct symbol *sym;
 100     int is_a_field_of_this;
 101   };
 102
 103 struct objc_class_str
 104   {
 105     struct stoken stoken;
 106     struct type *type;
 107     int class;
 108   };
 109
 110
 111 /* For parsing of complicated types.
 112    An array should be preceded in the list by the size of the array.  */
 113 enum type_pieces
 114   {
 115     tp_end = -1,
 116     tp_pointer,
 117     tp_reference,
 118     tp_array,
 119     tp_function,
 120     tp_const,
 121     tp_volatile,
 122     tp_space_identifier,
 123     tp_type_stack
 124   };
 125 /* The stack can contain either an enum type_pieces or an int.  */
 126 union type_stack_elt
 127   {
 128     enum type_pieces piece;
 129     int int_val;
 130     struct type_stack *stack_val;
 131   };
 132
 133 /* The type stack is an instance of this structure.  */
 134
 135 struct type_stack
 136 {
 137   /* Elements on the stack.  */
 138   union type_stack_elt *elements;
 139   /* Current stack depth.  */
 140   int depth;
 141   /* Allocated size of stack.  */
 142   int size;
 143 };
 144
 145 /* Helper function to initialize the expout, expout_size, expout_ptr
 146    trio before it is used to store expression elements created during
 147    the parsing of an expression.  INITIAL_SIZE is the initial size of
 148    the expout array.  LANG is the language used to parse the expression.
 149    And GDBARCH is the gdbarch to use during parsing.  */
 150
 151 extern void initialize_expout (int, const struct language_defn *,
 152                                struct gdbarch *);
 153
 154 /* Helper function that frees any unsed space in the expout array.
 155    It is generally used when the parser has just been parsed and
 156    created.  */
 157
 158 extern void reallocate_expout (void);
 159
 160 /* Reverse an expression from suffix form (in which it is constructed)
 161    to prefix form (in which we can conveniently print or execute it).
 162    Ordinarily this always returns -1.  However, if EXPOUT_LAST_STRUCT
 163    is not -1 (i.e., we are trying to complete a field name), it will
 164    return the index of the subexpression which is the left-hand-side
 165    of the struct operation at EXPOUT_LAST_STRUCT.  */
 166
 167 extern int prefixify_expression (struct expression *expr);
 168
 169 extern void write_exp_elt_opcode (enum exp_opcode);
 170
 171 extern void write_exp_elt_sym (struct symbol *);
 172
 173 extern void write_exp_elt_longcst (LONGEST);
 174
 175 extern void write_exp_elt_dblcst (DOUBLEST);
 176
 177 extern void write_exp_elt_decfloatcst (gdb_byte *);
 178
 179 extern void write_exp_elt_type (struct type *);
 180
 181 extern void write_exp_elt_intern (struct internalvar *);
 182
 183 extern void write_exp_string (struct stoken);
 184
 185 void write_exp_string_vector (int type, struct stoken_vector *vec);
 186
 187 extern void write_exp_bitstring (struct stoken);
 188
 189 extern void write_exp_elt_block (struct block *);
 190
 191 extern void write_exp_elt_objfile (struct objfile *objfile);
 192
 193 extern void write_exp_msymbol (struct minimal_symbol *);
 194
 195 extern void write_dollar_variable (struct stoken str);
 196
 197 extern void mark_struct_expression (void);
 198
 199 extern char *find_template_name_end (char *);
 200
 201 extern void start_arglist (void);
 202
 203 extern int end_arglist (void);
 204
 205 extern char *copy_name (struct stoken);
 206
 207 extern void insert_type (enum type_pieces);
 208
 209 extern void push_type (enum type_pieces);
 210
 211 extern void push_type_int (int);
 212
 213 extern void insert_type_address_space (char *);
 214
 215 extern enum type_pieces pop_type (void);
 216
 217 extern int pop_type_int (void);
 218
 219 extern struct type_stack *get_type_stack (void);
 220
 221 extern struct type_stack *append_type_stack (struct type_stack *to,
 222                                              struct type_stack *from);
 223
 224 extern void push_type_stack (struct type_stack *stack);
 225
 226 extern void type_stack_cleanup (void *arg);
 227
 228 extern int length_of_subexp (struct expression *, int);
 229
 230 extern int dump_subexp (struct expression *, struct ui_file *, int);
 231
 232 extern int dump_subexp_body_standard (struct expression *,
 233                                       struct ui_file *, int);
 234
 235 extern void operator_length (const struct expression *, int, int *, int *);
 236
 237 extern void operator_length_standard (const struct expression *, int, int *,
 238                                       int *);
 239
 240 extern int operator_check_standard (struct expression *exp, int pos,
 241                                     int (*objfile_func)
 242                                       (struct objfile *objfile, void *data),
 243                                     void *data);
 244
 245 extern char *op_name_standard (enum exp_opcode);
 246
 247 extern struct type *follow_types (struct type *);
 248
 249 extern void null_post_parser (struct expression **, int);
 250
 251 extern int parse_float (const char *p, int len, DOUBLEST *d,
 252                         const char **suffix);
 253
 254 extern int parse_c_float (struct gdbarch *gdbarch, const char *p, int len,
 255                           DOUBLEST *d, struct type **t);
 256
 257 /* During parsing of a C expression, the pointer to the next character
 258    is in this variable.  */
 259
 260 extern char *lexptr;
 261
 262 /* After a token has been recognized, this variable points to it.
 263    Currently used only for error reporting.  */
 264 extern char *prev_lexptr;
 265
 266 /* Current depth in parentheses within the expression.  */
 267
 268 extern int paren_depth;
 269
 270 /* Nonzero means stop parsing on first comma (if not within parentheses).  */
 271
 272 extern int comma_terminates;
 273 \f
 274 /* These codes indicate operator precedences for expression printing,
 275    least tightly binding first.  */
 276 /* Adding 1 to a precedence value is done for binary operators,
 277    on the operand which is more tightly bound, so that operators
 278    of equal precedence within that operand will get parentheses.  */
 279 /* PREC_HYPER and PREC_ABOVE_COMMA are not the precedence of any operator;
 280    they are used as the "surrounding precedence" to force
 281    various kinds of things to be parenthesized.  */
 282 enum precedence
 283   {
 284     PREC_NULL, PREC_COMMA, PREC_ABOVE_COMMA, PREC_ASSIGN, PREC_LOGICAL_OR,
 285     PREC_LOGICAL_AND, PREC_BITWISE_IOR, PREC_BITWISE_AND, PREC_BITWISE_XOR,
 286     PREC_EQUAL, PREC_ORDER, PREC_SHIFT, PREC_ADD, PREC_MUL, PREC_REPEAT,
 287     PREC_HYPER, PREC_PREFIX, PREC_SUFFIX, PREC_BUILTIN_FUNCTION
 288   };
 289
 290 /* Table mapping opcodes into strings for printing operators
 291    and precedences of the operators.  */
 292
 293 struct op_print
 294   {
 295     char *string;
 296     enum exp_opcode opcode;
 297     /* Precedence of operator.  These values are used only by comparisons.  */
 298     enum precedence precedence;
 299
 300     /* For a binary operator:  1 iff right associate.
 301        For a unary operator:  1 iff postfix.  */
 302     int right_assoc;
 303   };
 304
 305 /* Information needed to print, prefixify, and evaluate expressions for
 306    a given language.  */
 307
 308 struct exp_descriptor
 309   {
 310     /* Print subexpression.  */
 311     void (*print_subexp) (struct expression *, int *, struct ui_file *,
 312                           enum precedence);
 313
 314     /* Returns number of exp_elements needed to represent an operator and
 315        the number of subexpressions it takes.  */
 316     void (*operator_length) (const struct expression*, int, int*, int *);
 317
 318     /* Call TYPE_FUNC and OBJFILE_FUNC for any TYPE and OBJFILE found being
 319        referenced by the single operator of EXP at position POS.  Operator
 320        parameters are located at positive (POS + number) offsets in EXP.
 321        The functions should never be called with NULL TYPE or NULL OBJFILE.
 322        Functions should get passed an arbitrary caller supplied DATA pointer.
 323        If any of the functions returns non-zero value then (any other) non-zero
 324        value should be immediately returned to the caller.  Otherwise zero
 325        should be returned.  */
 326     int (*operator_check) (struct expression *exp, int pos,
 327                            int (*objfile_func) (struct objfile *objfile,
 328                                                 void *data),
 329                            void *data);
 330
 331     /* Name of this operator for dumping purposes.  */
 332     char *(*op_name) (enum exp_opcode);
 333
 334     /* Dump the rest of this (prefix) expression after the operator
 335        itself has been printed.  See dump_subexp_body_standard in
 336        (expprint.c).  */
 337     int (*dump_subexp_body) (struct expression *, struct ui_file *, int);
 338
 339     /* Evaluate an expression.  */
 340     struct value *(*evaluate_exp) (struct type *, struct expression *,
 341                                    int *, enum noside);
 342   };
 343
 344
 345 /* Default descriptor containing standard definitions of all
 346    elements.  */
 347 extern const struct exp_descriptor exp_descriptor_standard;
 348
 349 /* Functions used by language-specific extended operators to (recursively)
 350    print/dump subexpressions.  */
 351
 352 extern void print_subexp (struct expression *, int *, struct ui_file *,
 353                           enum precedence);
 354
 355 extern void print_subexp_standard (struct expression *, int *,
 356                                    struct ui_file *, enum precedence);
 357
 358 /* Function used to avoid direct calls to fprintf
 359    in the code generated by the bison parser.  */
 360
 361 extern void parser_fprintf (FILE *, const char *, ...) ATTRIBUTE_PRINTF (2, 3);
 362
 363 extern int exp_uses_objfile (struct expression *exp, struct objfile *objfile);
 364
 365 #endif /* PARSER_DEFS_H */