gdb/parser-defs.h

   1 /* Parser definitions for GDB.
   2
   3    Copyright (C) 1986-2013 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
  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 const 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 const 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 const 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 typedef struct type *type_ptr;
 111 DEF_VEC_P (type_ptr);
 112
 113 /* For parsing of complicated types.
 114    An array should be preceded in the list by the size of the array.  */
 115 enum type_pieces
 116   {
 117     tp_end = -1,
 118     tp_pointer,
 119     tp_reference,
 120     tp_array,
 121     tp_function,
 122     tp_function_with_arguments,
 123     tp_const,
 124     tp_volatile,
 125     tp_space_identifier,
 126     tp_type_stack
 127   };
 128 /* The stack can contain either an enum type_pieces or an int.  */
 129 union type_stack_elt
 130   {
 131     enum type_pieces piece;
 132     int int_val;
 133     struct type_stack *stack_val;
 134     VEC (type_ptr) *typelist_val;
 135   };
 136
 137 /* The type stack is an instance of this structure.  */
 138
 139 struct type_stack
 140 {
 141   /* Elements on the stack.  */
 142   union type_stack_elt *elements;
 143   /* Current stack depth.  */
 144   int depth;
 145   /* Allocated size of stack.  */
 146   int size;
 147 };
 148
 149 /* Helper function to initialize the expout, expout_size, expout_ptr
 150    trio before it is used to store expression elements created during
 151    the parsing of an expression.  INITIAL_SIZE is the initial size of
 152    the expout array.  LANG is the language used to parse the expression.
 153    And GDBARCH is the gdbarch to use during parsing.  */
 154
 155 extern void initialize_expout (int, const struct language_defn *,
 156                                struct gdbarch *);
 157
 158 /* Helper function that frees any unsed space in the expout array.
 159    It is generally used when the parser has just been parsed and
 160    created.  */
 161
 162 extern void reallocate_expout (void);
 163
 164 /* Reverse an expression from suffix form (in which it is constructed)
 165    to prefix form (in which we can conveniently print or execute it).
 166    Ordinarily this always returns -1.  However, if EXPOUT_LAST_STRUCT
 167    is not -1 (i.e., we are trying to complete a field name), it will
 168    return the index of the subexpression which is the left-hand-side
 169    of the struct operation at EXPOUT_LAST_STRUCT.  */
 170
 171 extern int prefixify_expression (struct expression *expr);
 172
 173 extern void write_exp_elt_opcode (enum exp_opcode);
 174
 175 extern void write_exp_elt_sym (struct symbol *);
 176
 177 extern void write_exp_elt_longcst (LONGEST);
 178
 179 extern void write_exp_elt_dblcst (DOUBLEST);
 180
 181 extern void write_exp_elt_decfloatcst (gdb_byte *);
 182
 183 extern void write_exp_elt_type (struct type *);
 184
 185 extern void write_exp_elt_intern (struct internalvar *);
 186
 187 extern void write_exp_string (struct stoken);
 188
 189 void write_exp_string_vector (int type, struct stoken_vector *vec);
 190
 191 extern void write_exp_bitstring (struct stoken);
 192
 193 extern void write_exp_elt_block (const struct block *);
 194
 195 extern void write_exp_elt_objfile (struct objfile *objfile);
 196
 197 extern void write_exp_msymbol (struct minimal_symbol *);
 198
 199 extern void write_dollar_variable (struct stoken str);
 200
 201 extern void mark_struct_expression (void);
 202
 203 extern char *find_template_name_end (char *);
 204
 205 extern void start_arglist (void);
 206
 207 extern int end_arglist (void);
 208
 209 extern char *copy_name (struct stoken);
 210
 211 extern void insert_type (enum type_pieces);
 212
 213 extern void push_type (enum type_pieces);
 214
 215 extern void push_type_int (int);
 216
 217 extern void insert_type_address_space (char *);
 218
 219 extern enum type_pieces pop_type (void);
 220
 221 extern int pop_type_int (void);
 222
 223 extern struct type_stack *get_type_stack (void);
 224
 225 extern struct type_stack *append_type_stack (struct type_stack *to,
 226                                              struct type_stack *from);
 227
 228 extern void push_type_stack (struct type_stack *stack);
 229
 230 extern void type_stack_cleanup (void *arg);
 231
 232 extern void push_typelist (VEC (type_ptr) *typelist);
 233
 234 extern int length_of_subexp (struct expression *, int);
 235
 236 extern int dump_subexp (struct expression *, struct ui_file *, int);
 237
 238 extern int dump_subexp_body_standard (struct expression *,
 239                                       struct ui_file *, int);
 240
 241 extern void operator_length (const struct expression *, int, int *, int *);
 242
 243 extern void operator_length_standard (const struct expression *, int, int *,
 244                                       int *);
 245
 246 extern int operator_check_standard (struct expression *exp, int pos,
 247                                     int (*objfile_func)
 248                                       (struct objfile *objfile, void *data),
 249                                     void *data);
 250
 251 extern char *op_name_standard (enum exp_opcode);
 252
 253 extern struct type *follow_types (struct type *);
 254
 255 extern void null_post_parser (struct expression **, int);
 256
 257 extern int parse_float (const char *p, int len, DOUBLEST *d,
 258                         const char **suffix);
 259
 260 extern int parse_c_float (struct gdbarch *gdbarch, const char *p, int len,
 261                           DOUBLEST *d, struct type **t);
 262
 263 /* During parsing of a C expression, the pointer to the next character
 264    is in this variable.  */
 265
 266 extern char *lexptr;
 267
 268 /* After a token has been recognized, this variable points to it.
 269    Currently used only for error reporting.  */
 270 extern char *prev_lexptr;
 271
 272 /* Current depth in parentheses within the expression.  */
 273
 274 extern int paren_depth;
 275
 276 /* Nonzero means stop parsing on first comma (if not within parentheses).  */
 277
 278 extern int comma_terminates;
 279 \f
 280 /* These codes indicate operator precedences for expression printing,
 281    least tightly binding first.  */
 282 /* Adding 1 to a precedence value is done for binary operators,
 283    on the operand which is more tightly bound, so that operators
 284    of equal precedence within that operand will get parentheses.  */
 285 /* PREC_HYPER and PREC_ABOVE_COMMA are not the precedence of any operator;
 286    they are used as the "surrounding precedence" to force
 287    various kinds of things to be parenthesized.  */
 288 enum precedence
 289   {
 290     PREC_NULL, PREC_COMMA, PREC_ABOVE_COMMA, PREC_ASSIGN, PREC_LOGICAL_OR,
 291     PREC_LOGICAL_AND, PREC_BITWISE_IOR, PREC_BITWISE_AND, PREC_BITWISE_XOR,
 292     PREC_EQUAL, PREC_ORDER, PREC_SHIFT, PREC_ADD, PREC_MUL, PREC_REPEAT,
 293     PREC_HYPER, PREC_PREFIX, PREC_SUFFIX, PREC_BUILTIN_FUNCTION
 294   };
 295
 296 /* Table mapping opcodes into strings for printing operators
 297    and precedences of the operators.  */
 298
 299 struct op_print
 300   {
 301     char *string;
 302     enum exp_opcode opcode;
 303     /* Precedence of operator.  These values are used only by comparisons.  */
 304     enum precedence precedence;
 305
 306     /* For a binary operator:  1 iff right associate.
 307        For a unary operator:  1 iff postfix.  */
 308     int right_assoc;
 309   };
 310
 311 /* Information needed to print, prefixify, and evaluate expressions for
 312    a given language.  */
 313
 314 struct exp_descriptor
 315   {
 316     /* Print subexpression.  */
 317     void (*print_subexp) (struct expression *, int *, struct ui_file *,
 318                           enum precedence);
 319
 320     /* Returns number of exp_elements needed to represent an operator and
 321        the number of subexpressions it takes.  */
 322     void (*operator_length) (const struct expression*, int, int*, int *);
 323
 324     /* Call TYPE_FUNC and OBJFILE_FUNC for any TYPE and OBJFILE found being
 325        referenced by the single operator of EXP at position POS.  Operator
 326        parameters are located at positive (POS + number) offsets in EXP.
 327        The functions should never be called with NULL TYPE or NULL OBJFILE.
 328        Functions should get passed an arbitrary caller supplied DATA pointer.
 329        If any of the functions returns non-zero value then (any other) non-zero
 330        value should be immediately returned to the caller.  Otherwise zero
 331        should be returned.  */
 332     int (*operator_check) (struct expression *exp, int pos,
 333                            int (*objfile_func) (struct objfile *objfile,
 334                                                 void *data),
 335                            void *data);
 336
 337     /* Name of this operator for dumping purposes.
 338        The returned value should never be NULL, even if EXP_OPCODE is
 339        an unknown opcode (a string containing an image of the numeric
 340        value of the opcode can be returned, for instance).  */
 341     char *(*op_name) (enum exp_opcode);
 342
 343     /* Dump the rest of this (prefix) expression after the operator
 344        itself has been printed.  See dump_subexp_body_standard in
 345        (expprint.c).  */
 346     int (*dump_subexp_body) (struct expression *, struct ui_file *, int);
 347
 348     /* Evaluate an expression.  */
 349     struct value *(*evaluate_exp) (struct type *, struct expression *,
 350                                    int *, enum noside);
 351   };
 352
 353
 354 /* Default descriptor containing standard definitions of all
 355    elements.  */
 356 extern const struct exp_descriptor exp_descriptor_standard;
 357
 358 /* Functions used by language-specific extended operators to (recursively)
 359    print/dump subexpressions.  */
 360
 361 extern void print_subexp (struct expression *, int *, struct ui_file *,
 362                           enum precedence);
 363
 364 extern void print_subexp_standard (struct expression *, int *,
 365                                    struct ui_file *, enum precedence);
 366
 367 /* Function used to avoid direct calls to fprintf
 368    in the code generated by the bison parser.  */
 369
 370 extern void parser_fprintf (FILE *, const char *, ...) ATTRIBUTE_PRINTF (2, 3);
 371
 372 extern int exp_uses_objfile (struct expression *exp, struct objfile *objfile);
 373
 374 extern void mark_completion_tag (enum type_code, const char *ptr,
 375                                  int length);
 376
 377 #endif /* PARSER_DEFS_H */
 378