gdb/parser-defs.h

   1 /* Parser definitions for GDB.
   2
   3    Copyright (C) 1986-2016 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 /* Number of arguments seen so far in innermost function call.  */
  71 extern int arglist_len;
  72
  73 /* A string token, either a char-string or bit-string.  Char-strings are
  74    used, for example, for the names of symbols.  */
  75
  76 struct stoken
  77   {
  78     /* Pointer to first byte of char-string or first bit of bit-string.  */
  79     const char *ptr;
  80     /* Length of string in bytes for char-string or bits for bit-string.  */
  81     int length;
  82   };
  83
  84 struct typed_stoken
  85   {
  86     /* A language-specific type field.  */
  87     int type;
  88     /* Pointer to first byte of char-string or first bit of bit-string.  */
  89     char *ptr;
  90     /* Length of string in bytes for char-string or bits for bit-string.  */
  91     int length;
  92   };
  93
  94 struct stoken_vector
  95   {
  96     int len;
  97     struct typed_stoken *tokens;
  98   };
  99
 100 struct ttype
 101   {
 102     struct stoken stoken;
 103     struct type *type;
 104   };
 105
 106 struct symtoken
 107   {
 108     struct stoken stoken;
 109     struct block_symbol sym;
 110     int is_a_field_of_this;
 111   };
 112
 113 struct objc_class_str
 114   {
 115     struct stoken stoken;
 116     struct type *type;
 117     int theclass;
 118   };
 119
 120 typedef struct type *type_ptr;
 121 DEF_VEC_P (type_ptr);
 122
 123 /* For parsing of complicated types.
 124    An array should be preceded in the list by the size of the array.  */
 125 enum type_pieces
 126   {
 127     tp_end = -1,
 128     tp_pointer,
 129     tp_reference,
 130     tp_array,
 131     tp_function,
 132     tp_function_with_arguments,
 133     tp_const,
 134     tp_volatile,
 135     tp_space_identifier,
 136     tp_type_stack
 137   };
 138 /* The stack can contain either an enum type_pieces or an int.  */
 139 union type_stack_elt
 140   {
 141     enum type_pieces piece;
 142     int int_val;
 143     struct type_stack *stack_val;
 144     VEC (type_ptr) *typelist_val;
 145   };
 146
 147 /* The type stack is an instance of this structure.  */
 148
 149 struct type_stack
 150 {
 151   /* Elements on the stack.  */
 152   union type_stack_elt *elements;
 153   /* Current stack depth.  */
 154   int depth;
 155   /* Allocated size of stack.  */
 156   int size;
 157 };
 158
 159 /* Helper function to initialize the expout, expout_size, expout_ptr
 160    trio inside PS before it is used to store expression elements created
 161    during the parsing of an expression.  INITIAL_SIZE is the initial size of
 162    the expout array.  LANG is the language used to parse the expression.
 163    And GDBARCH is the gdbarch to use during parsing.  */
 164
 165 extern void initialize_expout (struct parser_state *ps,
 166                                size_t initial_size,
 167                                const struct language_defn *lang,
 168                                struct gdbarch *gdbarch);
 169
 170 /* Helper function that reallocates the EXPOUT inside PS in order to
 171    eliminate any unused space.  It is generally used when the expression
 172    has just been parsed and created.  */
 173
 174 extern void reallocate_expout (struct parser_state *ps);
 175
 176 /* Reverse an expression from suffix form (in which it is constructed)
 177    to prefix form (in which we can conveniently print or execute it).
 178    Ordinarily this always returns -1.  However, if EXPOUT_LAST_STRUCT
 179    is not -1 (i.e., we are trying to complete a field name), it will
 180    return the index of the subexpression which is the left-hand-side
 181    of the struct operation at EXPOUT_LAST_STRUCT.  */
 182
 183 extern int prefixify_expression (struct expression *expr);
 184
 185 extern void write_exp_elt_opcode (struct parser_state *, enum exp_opcode);
 186
 187 extern void write_exp_elt_sym (struct parser_state *, struct symbol *);
 188
 189 extern void write_exp_elt_longcst (struct parser_state *, LONGEST);
 190
 191 extern void write_exp_elt_dblcst (struct parser_state *, DOUBLEST);
 192
 193 extern void write_exp_elt_decfloatcst (struct parser_state *, gdb_byte *);
 194
 195 extern void write_exp_elt_type (struct parser_state *, struct type *);
 196
 197 extern void write_exp_elt_intern (struct parser_state *, struct internalvar *);
 198
 199 extern void write_exp_string (struct parser_state *, struct stoken);
 200
 201 void write_exp_string_vector (struct parser_state *, int type,
 202                               struct stoken_vector *vec);
 203
 204 extern void write_exp_bitstring (struct parser_state *, struct stoken);
 205
 206 extern void write_exp_elt_block (struct parser_state *, const struct block *);
 207
 208 extern void write_exp_elt_objfile (struct parser_state *,
 209                                    struct objfile *objfile);
 210
 211 extern void write_exp_msymbol (struct parser_state *,
 212                                struct bound_minimal_symbol);
 213
 214 extern void write_dollar_variable (struct parser_state *, struct stoken str);
 215
 216 extern void mark_struct_expression (struct parser_state *);
 217
 218 extern const char *find_template_name_end (const char *);
 219
 220 extern void start_arglist (void);
 221
 222 extern int end_arglist (void);
 223
 224 extern char *copy_name (struct stoken);
 225
 226 extern void insert_type (enum type_pieces);
 227
 228 extern void push_type (enum type_pieces);
 229
 230 extern void push_type_int (int);
 231
 232 extern void insert_type_address_space (struct parser_state *, char *);
 233
 234 extern enum type_pieces pop_type (void);
 235
 236 extern int pop_type_int (void);
 237
 238 extern struct type_stack *get_type_stack (void);
 239
 240 extern struct type_stack *append_type_stack (struct type_stack *to,
 241                                              struct type_stack *from);
 242
 243 extern void push_type_stack (struct type_stack *stack);
 244
 245 extern void type_stack_cleanup (void *arg);
 246
 247 extern void push_typelist (VEC (type_ptr) *typelist);
 248
 249 extern int length_of_subexp (struct expression *, int);
 250
 251 extern int dump_subexp (struct expression *, struct ui_file *, int);
 252
 253 extern int dump_subexp_body_standard (struct expression *,
 254                                       struct ui_file *, int);
 255
 256 extern void operator_length (const struct expression *, int, int *, int *);
 257
 258 extern void operator_length_standard (const struct expression *, int, int *,
 259                                       int *);
 260
 261 extern int operator_check_standard (struct expression *exp, int pos,
 262                                     int (*objfile_func)
 263                                       (struct objfile *objfile, void *data),
 264                                     void *data);
 265
 266 extern char *op_name_standard (enum exp_opcode);
 267
 268 extern struct type *follow_types (struct type *);
 269
 270 extern void null_post_parser (struct expression **, int);
 271
 272 extern int parse_float (const char *p, int len, DOUBLEST *d,
 273                         const char **suffix);
 274
 275 extern int parse_c_float (struct gdbarch *gdbarch, const char *p, int len,
 276                           DOUBLEST *d, struct type **t);
 277
 278 /* During parsing of a C expression, the pointer to the next character
 279    is in this variable.  */
 280
 281 extern const char *lexptr;
 282
 283 /* After a token has been recognized, this variable points to it.
 284    Currently used only for error reporting.  */
 285 extern const char *prev_lexptr;
 286
 287 /* Current depth in parentheses within the expression.  */
 288
 289 extern int paren_depth;
 290
 291 /* Nonzero means stop parsing on first comma (if not within parentheses).  */
 292
 293 extern int comma_terminates;
 294 \f
 295 /* These codes indicate operator precedences for expression printing,
 296    least tightly binding first.  */
 297 /* Adding 1 to a precedence value is done for binary operators,
 298    on the operand which is more tightly bound, so that operators
 299    of equal precedence within that operand will get parentheses.  */
 300 /* PREC_HYPER and PREC_ABOVE_COMMA are not the precedence of any operator;
 301    they are used as the "surrounding precedence" to force
 302    various kinds of things to be parenthesized.  */
 303 enum precedence
 304   {
 305     PREC_NULL, PREC_COMMA, PREC_ABOVE_COMMA, PREC_ASSIGN, PREC_LOGICAL_OR,
 306     PREC_LOGICAL_AND, PREC_BITWISE_IOR, PREC_BITWISE_AND, PREC_BITWISE_XOR,
 307     PREC_EQUAL, PREC_ORDER, PREC_SHIFT, PREC_ADD, PREC_MUL, PREC_REPEAT,
 308     PREC_HYPER, PREC_PREFIX, PREC_SUFFIX, PREC_BUILTIN_FUNCTION
 309   };
 310
 311 /* Table mapping opcodes into strings for printing operators
 312    and precedences of the operators.  */
 313
 314 struct op_print
 315   {
 316     char *string;
 317     enum exp_opcode opcode;
 318     /* Precedence of operator.  These values are used only by comparisons.  */
 319     enum precedence precedence;
 320
 321     /* For a binary operator:  1 iff right associate.
 322        For a unary operator:  1 iff postfix.  */
 323     int right_assoc;
 324   };
 325
 326 /* Information needed to print, prefixify, and evaluate expressions for
 327    a given language.  */
 328
 329 struct exp_descriptor
 330   {
 331     /* Print subexpression.  */
 332     void (*print_subexp) (struct expression *, int *, struct ui_file *,
 333                           enum precedence);
 334
 335     /* Returns number of exp_elements needed to represent an operator and
 336        the number of subexpressions it takes.  */
 337     void (*operator_length) (const struct expression*, int, int*, int *);
 338
 339     /* Call OBJFILE_FUNC for any objfile found being referenced by the
 340        single operator of EXP at position POS.  Operator parameters are
 341        located at positive (POS + number) offsets in EXP.  OBJFILE_FUNC
 342        should never be called with NULL OBJFILE.  OBJFILE_FUNC should
 343        get passed an arbitrary caller supplied DATA pointer.  If it
 344        returns non-zero value then (any other) non-zero value should be
 345        immediately returned to the caller.  Otherwise zero should be
 346        returned.  */
 347     int (*operator_check) (struct expression *exp, int pos,
 348                            int (*objfile_func) (struct objfile *objfile,
 349                                                 void *data),
 350                            void *data);
 351
 352     /* Name of this operator for dumping purposes.
 353        The returned value should never be NULL, even if EXP_OPCODE is
 354        an unknown opcode (a string containing an image of the numeric
 355        value of the opcode can be returned, for instance).  */
 356     char *(*op_name) (enum exp_opcode);
 357
 358     /* Dump the rest of this (prefix) expression after the operator
 359        itself has been printed.  See dump_subexp_body_standard in
 360        (expprint.c).  */
 361     int (*dump_subexp_body) (struct expression *, struct ui_file *, int);
 362
 363     /* Evaluate an expression.  */
 364     struct value *(*evaluate_exp) (struct type *, struct expression *,
 365                                    int *, enum noside);
 366   };
 367
 368
 369 /* Default descriptor containing standard definitions of all
 370    elements.  */
 371 extern const struct exp_descriptor exp_descriptor_standard;
 372
 373 /* Functions used by language-specific extended operators to (recursively)
 374    print/dump subexpressions.  */
 375
 376 extern void print_subexp (struct expression *, int *, struct ui_file *,
 377                           enum precedence);
 378
 379 extern void print_subexp_standard (struct expression *, int *,
 380                                    struct ui_file *, enum precedence);
 381
 382 /* Function used to avoid direct calls to fprintf
 383    in the code generated by the bison parser.  */
 384
 385 extern void parser_fprintf (FILE *, const char *, ...) ATTRIBUTE_PRINTF (2, 3);
 386
 387 extern int exp_uses_objfile (struct expression *exp, struct objfile *objfile);
 388
 389 extern void mark_completion_tag (enum type_code, const char *ptr,
 390                                  int length);
 391
 392 /* Reallocate the `expout' pointer inside PS so that it can accommodate
 393    at least LENELT expression elements.  This function does nothing if
 394    there is enough room for the elements.  */
 395
 396 extern void increase_expout_size (struct parser_state *ps, size_t lenelt);
 397
 398 #endif /* PARSER_DEFS_H */
 399