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