gdb/m2-lang.c

   1 /* Modula 2 language support routines for GDB, the GNU debugger.
   2
   3    Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 2000, 2002, 2003, 2004,
   4    2005, 2007, 2008 Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "defs.h"
  22 #include "symtab.h"
  23 #include "gdbtypes.h"
  24 #include "expression.h"
  25 #include "parser-defs.h"
  26 #include "language.h"
  27 #include "m2-lang.h"
  28 #include "c-lang.h"
  29 #include "valprint.h"
  30
  31 extern void _initialize_m2_language (void);
  32 static void m2_printchar (int, struct ui_file *);
  33 static void m2_emit_char (int, struct ui_file *, int);
  34
  35 /* Print the character C on STREAM as part of the contents of a literal
  36    string whose delimiter is QUOTER.  Note that that format for printing
  37    characters and strings is language specific.
  38    FIXME:  This is a copy of the same function from c-exp.y.  It should
  39    be replaced with a true Modula version.  */
  40
  41 static void
  42 m2_emit_char (int c, struct ui_file *stream, int quoter)
  43 {
  44
  45   c &= 0xFF;                    /* Avoid sign bit follies */
  46
  47   if (PRINT_LITERAL_FORM (c))
  48     {
  49       if (c == '\\' || c == quoter)
  50         {
  51           fputs_filtered ("\\", stream);
  52         }
  53       fprintf_filtered (stream, "%c", c);
  54     }
  55   else
  56     {
  57       switch (c)
  58         {
  59         case '\n':
  60           fputs_filtered ("\\n", stream);
  61           break;
  62         case '\b':
  63           fputs_filtered ("\\b", stream);
  64           break;
  65         case '\t':
  66           fputs_filtered ("\\t", stream);
  67           break;
  68         case '\f':
  69           fputs_filtered ("\\f", stream);
  70           break;
  71         case '\r':
  72           fputs_filtered ("\\r", stream);
  73           break;
  74         case '\033':
  75           fputs_filtered ("\\e", stream);
  76           break;
  77         case '\007':
  78           fputs_filtered ("\\a", stream);
  79           break;
  80         default:
  81           fprintf_filtered (stream, "\\%.3o", (unsigned int) c);
  82           break;
  83         }
  84     }
  85 }
  86
  87 /* FIXME:  This is a copy of the same function from c-exp.y.  It should
  88    be replaced with a true Modula version.  */
  89
  90 static void
  91 m2_printchar (int c, struct ui_file *stream)
  92 {
  93   fputs_filtered ("'", stream);
  94   LA_EMIT_CHAR (c, stream, '\'');
  95   fputs_filtered ("'", stream);
  96 }
  97
  98 /* Print the character string STRING, printing at most LENGTH characters.
  99    Printing stops early if the number hits print_max; repeat counts
 100    are printed as appropriate.  Print ellipses at the end if we
 101    had to stop before printing LENGTH characters, or if FORCE_ELLIPSES.
 102    FIXME:  This is a copy of the same function from c-exp.y.  It should
 103    be replaced with a true Modula version.  */
 104
 105 static void
 106 m2_printstr (struct ui_file *stream, const gdb_byte *string,
 107              unsigned int length, int width, int force_ellipses,
 108              const struct value_print_options *options)
 109 {
 110   unsigned int i;
 111   unsigned int things_printed = 0;
 112   int in_quotes = 0;
 113   int need_comma = 0;
 114
 115   if (length == 0)
 116     {
 117       fputs_filtered ("\"\"", gdb_stdout);
 118       return;
 119     }
 120
 121   for (i = 0; i < length && things_printed < options->print_max; ++i)
 122     {
 123       /* Position of the character we are examining
 124          to see whether it is repeated.  */
 125       unsigned int rep1;
 126       /* Number of repetitions we have detected so far.  */
 127       unsigned int reps;
 128
 129       QUIT;
 130
 131       if (need_comma)
 132         {
 133           fputs_filtered (", ", stream);
 134           need_comma = 0;
 135         }
 136
 137       rep1 = i + 1;
 138       reps = 1;
 139       while (rep1 < length && string[rep1] == string[i])
 140         {
 141           ++rep1;
 142           ++reps;
 143         }
 144
 145       if (reps > options->repeat_count_threshold)
 146         {
 147           if (in_quotes)
 148             {
 149               if (options->inspect_it)
 150                 fputs_filtered ("\\\", ", stream);
 151               else
 152                 fputs_filtered ("\", ", stream);
 153               in_quotes = 0;
 154             }
 155           m2_printchar (string[i], stream);
 156           fprintf_filtered (stream, " <repeats %u times>", reps);
 157           i = rep1 - 1;
 158           things_printed += options->repeat_count_threshold;
 159           need_comma = 1;
 160         }
 161       else
 162         {
 163           if (!in_quotes)
 164             {
 165               if (options->inspect_it)
 166                 fputs_filtered ("\\\"", stream);
 167               else
 168                 fputs_filtered ("\"", stream);
 169               in_quotes = 1;
 170             }
 171           LA_EMIT_CHAR (string[i], stream, '"');
 172           ++things_printed;
 173         }
 174     }
 175
 176   /* Terminate the quotes if necessary.  */
 177   if (in_quotes)
 178     {
 179       if (options->inspect_it)
 180         fputs_filtered ("\\\"", stream);
 181       else
 182         fputs_filtered ("\"", stream);
 183     }
 184
 185   if (force_ellipses || i < length)
 186     fputs_filtered ("...", stream);
 187 }
 188
 189 static struct value *
 190 evaluate_subexp_modula2 (struct type *expect_type, struct expression *exp,
 191                          int *pos, enum noside noside)
 192 {
 193   enum exp_opcode op = exp->elts[*pos].opcode;
 194   struct value *arg1;
 195   struct value *arg2;
 196   struct type *type;
 197   switch (op)
 198     {
 199     case UNOP_HIGH:
 200       (*pos)++;
 201       arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
 202
 203       if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
 204         return arg1;
 205       else
 206         {
 207           arg1 = coerce_ref (arg1);
 208           type = check_typedef (value_type (arg1));
 209
 210           if (m2_is_unbounded_array (type))
 211             {
 212               struct value *temp = arg1;
 213               type = TYPE_FIELD_TYPE (type, 1);
 214               /* i18n: Do not translate the "_m2_high" part!  */
 215               arg1 = value_struct_elt (&temp, NULL, "_m2_high", NULL,
 216                                        _("unbounded structure "
 217                                          "missing _m2_high field"));
 218
 219               if (value_type (arg1) != type)
 220                 arg1 = value_cast (type, arg1);
 221             }
 222         }
 223       return arg1;
 224
 225     case BINOP_SUBSCRIPT:
 226       (*pos)++;
 227       arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
 228       arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
 229       if (noside == EVAL_SKIP)
 230         goto nosideret;
 231       /* If the user attempts to subscript something that is not an
 232          array or pointer type (like a plain int variable for example),
 233          then report this as an error.  */
 234
 235       arg1 = coerce_ref (arg1);
 236       type = check_typedef (value_type (arg1));
 237
 238       if (m2_is_unbounded_array (type))
 239         {
 240           struct value *temp = arg1;
 241           type = TYPE_FIELD_TYPE (type, 0);
 242           if (type == NULL || (TYPE_CODE (type) != TYPE_CODE_PTR)) {
 243             warning (_("internal error: unbounded array structure is unknown"));
 244             return evaluate_subexp_standard (expect_type, exp, pos, noside);
 245           }
 246           /* i18n: Do not translate the "_m2_contents" part!  */
 247           arg1 = value_struct_elt (&temp, NULL, "_m2_contents", NULL,
 248                                    _("unbounded structure "
 249                                      "missing _m2_contents field"));
 250
 251           if (value_type (arg1) != type)
 252             arg1 = value_cast (type, arg1);
 253
 254           type = check_typedef (value_type (arg1));
 255           return value_ind (value_ptradd (arg1, arg2));
 256         }
 257       else
 258         if (TYPE_CODE (type) != TYPE_CODE_ARRAY)
 259           {
 260             if (TYPE_NAME (type))
 261               error (_("cannot subscript something of type `%s'"),
 262                      TYPE_NAME (type));
 263             else
 264               error (_("cannot subscript requested type"));
 265           }
 266
 267       if (noside == EVAL_AVOID_SIDE_EFFECTS)
 268         return value_zero (TYPE_TARGET_TYPE (type), VALUE_LVAL (arg1));
 269       else
 270         return value_subscript (arg1, arg2);
 271
 272     default:
 273       return evaluate_subexp_standard (expect_type, exp, pos, noside);
 274     }
 275
 276  nosideret:
 277   return value_from_longest (builtin_type_int8, (LONGEST) 1);
 278 }
 279 \f
 280
 281 /* Table of operators and their precedences for printing expressions.  */
 282
 283 static const struct op_print m2_op_print_tab[] =
 284 {
 285   {"+", BINOP_ADD, PREC_ADD, 0},
 286   {"+", UNOP_PLUS, PREC_PREFIX, 0},
 287   {"-", BINOP_SUB, PREC_ADD, 0},
 288   {"-", UNOP_NEG, PREC_PREFIX, 0},
 289   {"*", BINOP_MUL, PREC_MUL, 0},
 290   {"/", BINOP_DIV, PREC_MUL, 0},
 291   {"DIV", BINOP_INTDIV, PREC_MUL, 0},
 292   {"MOD", BINOP_REM, PREC_MUL, 0},
 293   {":=", BINOP_ASSIGN, PREC_ASSIGN, 1},
 294   {"OR", BINOP_LOGICAL_OR, PREC_LOGICAL_OR, 0},
 295   {"AND", BINOP_LOGICAL_AND, PREC_LOGICAL_AND, 0},
 296   {"NOT", UNOP_LOGICAL_NOT, PREC_PREFIX, 0},
 297   {"=", BINOP_EQUAL, PREC_EQUAL, 0},
 298   {"<>", BINOP_NOTEQUAL, PREC_EQUAL, 0},
 299   {"<=", BINOP_LEQ, PREC_ORDER, 0},
 300   {">=", BINOP_GEQ, PREC_ORDER, 0},
 301   {">", BINOP_GTR, PREC_ORDER, 0},
 302   {"<", BINOP_LESS, PREC_ORDER, 0},
 303   {"^", UNOP_IND, PREC_PREFIX, 0},
 304   {"@", BINOP_REPEAT, PREC_REPEAT, 0},
 305   {"CAP", UNOP_CAP, PREC_BUILTIN_FUNCTION, 0},
 306   {"CHR", UNOP_CHR, PREC_BUILTIN_FUNCTION, 0},
 307   {"ORD", UNOP_ORD, PREC_BUILTIN_FUNCTION, 0},
 308   {"FLOAT", UNOP_FLOAT, PREC_BUILTIN_FUNCTION, 0},
 309   {"HIGH", UNOP_HIGH, PREC_BUILTIN_FUNCTION, 0},
 310   {"MAX", UNOP_MAX, PREC_BUILTIN_FUNCTION, 0},
 311   {"MIN", UNOP_MIN, PREC_BUILTIN_FUNCTION, 0},
 312   {"ODD", UNOP_ODD, PREC_BUILTIN_FUNCTION, 0},
 313   {"TRUNC", UNOP_TRUNC, PREC_BUILTIN_FUNCTION, 0},
 314   {NULL, 0, 0, 0}
 315 };
 316 \f
 317 /* The built-in types of Modula-2.  */
 318
 319 enum m2_primitive_types {
 320   m2_primitive_type_char,
 321   m2_primitive_type_int,
 322   m2_primitive_type_card,
 323   m2_primitive_type_real,
 324   m2_primitive_type_bool,
 325   nr_m2_primitive_types
 326 };
 327
 328 static void
 329 m2_language_arch_info (struct gdbarch *gdbarch,
 330                        struct language_arch_info *lai)
 331 {
 332   const struct builtin_m2_type *builtin = builtin_m2_type (gdbarch);
 333
 334   lai->string_char_type = builtin->builtin_char;
 335   lai->primitive_type_vector
 336     = GDBARCH_OBSTACK_CALLOC (gdbarch, nr_m2_primitive_types + 1,
 337                               struct type *);
 338
 339   lai->primitive_type_vector [m2_primitive_type_char]
 340     = builtin->builtin_char;
 341   lai->primitive_type_vector [m2_primitive_type_int]
 342     = builtin->builtin_int;
 343   lai->primitive_type_vector [m2_primitive_type_card]
 344     = builtin->builtin_card;
 345   lai->primitive_type_vector [m2_primitive_type_real]
 346     = builtin->builtin_real;
 347   lai->primitive_type_vector [m2_primitive_type_bool]
 348     = builtin->builtin_bool;
 349
 350   lai->bool_type_symbol = "BOOLEAN";
 351   lai->bool_type_default = builtin->builtin_bool;
 352 }
 353
 354 const struct exp_descriptor exp_descriptor_modula2 =
 355 {
 356   print_subexp_standard,
 357   operator_length_standard,
 358   op_name_standard,
 359   dump_subexp_body_standard,
 360   evaluate_subexp_modula2
 361 };
 362
 363 const struct language_defn m2_language_defn =
 364 {
 365   "modula-2",
 366   language_m2,
 367   range_check_on,
 368   type_check_on,
 369   case_sensitive_on,
 370   array_row_major,
 371   macro_expansion_no,
 372   &exp_descriptor_modula2,
 373   m2_parse,                     /* parser */
 374   m2_error,                     /* parser error function */
 375   null_post_parser,
 376   m2_printchar,                 /* Print character constant */
 377   m2_printstr,                  /* function to print string constant */
 378   m2_emit_char,                 /* Function to print a single character */
 379   m2_print_type,                /* Print a type using appropriate syntax */
 380   m2_print_typedef,             /* Print a typedef using appropriate syntax */
 381   m2_val_print,                 /* Print a value using appropriate syntax */
 382   c_value_print,                /* Print a top-level value */
 383   NULL,                         /* Language specific skip_trampoline */
 384   NULL,                         /* name_of_this */
 385   basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
 386   basic_lookup_transparent_type,/* lookup_transparent_type */
 387   NULL,                         /* Language specific symbol demangler */
 388   NULL,                         /* Language specific class_name_from_physname */
 389   m2_op_print_tab,              /* expression operators for printing */
 390   0,                            /* arrays are first-class (not c-style) */
 391   0,                            /* String lower bound */
 392   default_word_break_characters,
 393   default_make_symbol_completion_list,
 394   m2_language_arch_info,
 395   default_print_array_index,
 396   default_pass_by_reference,
 397   LANG_MAGIC
 398 };
 399
 400 static void *
 401 build_m2_types (struct gdbarch *gdbarch)
 402 {
 403   struct builtin_m2_type *builtin_m2_type
 404     = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct builtin_m2_type);
 405
 406   /* Modula-2 "pervasive" types.  NOTE:  these can be redefined!!! */
 407   builtin_m2_type->builtin_int =
 408     init_type (TYPE_CODE_INT,
 409                gdbarch_int_bit (gdbarch) / TARGET_CHAR_BIT,
 410                0, "INTEGER", (struct objfile *) NULL);
 411   builtin_m2_type->builtin_card =
 412     init_type (TYPE_CODE_INT,
 413                gdbarch_int_bit (gdbarch) / TARGET_CHAR_BIT,
 414                TYPE_FLAG_UNSIGNED,
 415                "CARDINAL", (struct objfile *) NULL);
 416   builtin_m2_type->builtin_real =
 417     init_type (TYPE_CODE_FLT,
 418                gdbarch_float_bit (gdbarch) / TARGET_CHAR_BIT,
 419                0,
 420                "REAL", (struct objfile *) NULL);
 421   builtin_m2_type->builtin_char =
 422     init_type (TYPE_CODE_CHAR, TARGET_CHAR_BIT / TARGET_CHAR_BIT,
 423                TYPE_FLAG_UNSIGNED,
 424                "CHAR", (struct objfile *) NULL);
 425   builtin_m2_type->builtin_bool =
 426     init_type (TYPE_CODE_BOOL,
 427                gdbarch_int_bit (gdbarch) / TARGET_CHAR_BIT,
 428                TYPE_FLAG_UNSIGNED,
 429                "BOOLEAN", (struct objfile *) NULL);
 430
 431   return builtin_m2_type;
 432 }
 433
 434 static struct gdbarch_data *m2_type_data;
 435
 436 const struct builtin_m2_type *
 437 builtin_m2_type (struct gdbarch *gdbarch)
 438 {
 439   return gdbarch_data (gdbarch, m2_type_data);
 440 }
 441
 442
 443 /* Initialization for Modula-2 */
 444
 445 void
 446 _initialize_m2_language (void)
 447 {
 448   m2_type_data = gdbarch_data_register_post_init (build_m2_types);
 449
 450   add_language (&m2_language_defn);
 451 }