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, 2009, 2010, 2011 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
31extern void _initialize_m2_language (void);
32static void m2_printchar (int, struct type *, struct ui_file *);
33static void m2_emit_char (int, struct type *, 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
41static void
42m2_emit_char (int c, struct type *type, 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
90static void
91m2_printchar (int c, struct type *type, struct ui_file *stream)
92{
93  fputs_filtered ("'", stream);
94  LA_EMIT_CHAR (c, type, 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
105static void
106m2_printstr (struct ui_file *stream, struct type *type, const gdb_byte *string,
107	     unsigned int length, const char *encoding, 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], type, 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], type, 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
189static struct value *
190evaluate_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
198  switch (op)
199    {
200    case UNOP_HIGH:
201      (*pos)++;
202      arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
203
204      if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
205	return arg1;
206      else
207	{
208	  arg1 = coerce_ref (arg1);
209	  type = check_typedef (value_type (arg1));
210
211	  if (m2_is_unbounded_array (type))
212	    {
213	      struct value *temp = arg1;
214
215	      type = TYPE_FIELD_TYPE (type, 1);
216	      /* i18n: Do not translate the "_m2_high" part!  */
217	      arg1 = value_struct_elt (&temp, NULL, "_m2_high", NULL,
218				       _("unbounded structure "
219					 "missing _m2_high field"));
220
221	      if (value_type (arg1) != type)
222		arg1 = value_cast (type, arg1);
223	    }
224	}
225      return arg1;
226
227    case BINOP_SUBSCRIPT:
228      (*pos)++;
229      arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
230      arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
231      if (noside == EVAL_SKIP)
232	goto nosideret;
233      /* If the user attempts to subscript something that is not an
234         array or pointer type (like a plain int variable for example),
235         then report this as an error.  */
236
237      arg1 = coerce_ref (arg1);
238      type = check_typedef (value_type (arg1));
239
240      if (m2_is_unbounded_array (type))
241	{
242	  struct value *temp = arg1;
243	  type = TYPE_FIELD_TYPE (type, 0);
244	  if (type == NULL || (TYPE_CODE (type) != TYPE_CODE_PTR))
245	    {
246	      warning (_("internal error: unbounded "
247			 "array structure is unknown"));
248	      return evaluate_subexp_standard (expect_type, exp, pos, noside);
249	    }
250	  /* i18n: Do not translate the "_m2_contents" part!  */
251	  arg1 = value_struct_elt (&temp, NULL, "_m2_contents", NULL,
252				   _("unbounded structure "
253				     "missing _m2_contents field"));
254
255	  if (value_type (arg1) != type)
256	    arg1 = value_cast (type, arg1);
257
258	  check_typedef (value_type (arg1));
259	  return value_ind (value_ptradd (arg1, value_as_long (arg2)));
260	}
261      else
262	if (TYPE_CODE (type) != TYPE_CODE_ARRAY)
263	  {
264	    if (TYPE_NAME (type))
265	      error (_("cannot subscript something of type `%s'"),
266		     TYPE_NAME (type));
267	    else
268	      error (_("cannot subscript requested type"));
269	  }
270
271      if (noside == EVAL_AVOID_SIDE_EFFECTS)
272	return value_zero (TYPE_TARGET_TYPE (type), VALUE_LVAL (arg1));
273      else
274	return value_subscript (arg1, value_as_long (arg2));
275
276    default:
277      return evaluate_subexp_standard (expect_type, exp, pos, noside);
278    }
279
280 nosideret:
281  return value_from_longest (builtin_type (exp->gdbarch)->builtin_int, 1);
282}
283
284
285/* Table of operators and their precedences for printing expressions.  */
286
287static const struct op_print m2_op_print_tab[] =
288{
289  {"+", BINOP_ADD, PREC_ADD, 0},
290  {"+", UNOP_PLUS, PREC_PREFIX, 0},
291  {"-", BINOP_SUB, PREC_ADD, 0},
292  {"-", UNOP_NEG, PREC_PREFIX, 0},
293  {"*", BINOP_MUL, PREC_MUL, 0},
294  {"/", BINOP_DIV, PREC_MUL, 0},
295  {"DIV", BINOP_INTDIV, PREC_MUL, 0},
296  {"MOD", BINOP_REM, PREC_MUL, 0},
297  {":=", BINOP_ASSIGN, PREC_ASSIGN, 1},
298  {"OR", BINOP_LOGICAL_OR, PREC_LOGICAL_OR, 0},
299  {"AND", BINOP_LOGICAL_AND, PREC_LOGICAL_AND, 0},
300  {"NOT", UNOP_LOGICAL_NOT, PREC_PREFIX, 0},
301  {"=", BINOP_EQUAL, PREC_EQUAL, 0},
302  {"<>", BINOP_NOTEQUAL, PREC_EQUAL, 0},
303  {"<=", BINOP_LEQ, PREC_ORDER, 0},
304  {">=", BINOP_GEQ, PREC_ORDER, 0},
305  {">", BINOP_GTR, PREC_ORDER, 0},
306  {"<", BINOP_LESS, PREC_ORDER, 0},
307  {"^", UNOP_IND, PREC_PREFIX, 0},
308  {"@", BINOP_REPEAT, PREC_REPEAT, 0},
309  {"CAP", UNOP_CAP, PREC_BUILTIN_FUNCTION, 0},
310  {"CHR", UNOP_CHR, PREC_BUILTIN_FUNCTION, 0},
311  {"ORD", UNOP_ORD, PREC_BUILTIN_FUNCTION, 0},
312  {"FLOAT", UNOP_FLOAT, PREC_BUILTIN_FUNCTION, 0},
313  {"HIGH", UNOP_HIGH, PREC_BUILTIN_FUNCTION, 0},
314  {"MAX", UNOP_MAX, PREC_BUILTIN_FUNCTION, 0},
315  {"MIN", UNOP_MIN, PREC_BUILTIN_FUNCTION, 0},
316  {"ODD", UNOP_ODD, PREC_BUILTIN_FUNCTION, 0},
317  {"TRUNC", UNOP_TRUNC, PREC_BUILTIN_FUNCTION, 0},
318  {NULL, 0, 0, 0}
319};
320
321/* The built-in types of Modula-2.  */
322
323enum m2_primitive_types {
324  m2_primitive_type_char,
325  m2_primitive_type_int,
326  m2_primitive_type_card,
327  m2_primitive_type_real,
328  m2_primitive_type_bool,
329  nr_m2_primitive_types
330};
331
332static void
333m2_language_arch_info (struct gdbarch *gdbarch,
334		       struct language_arch_info *lai)
335{
336  const struct builtin_m2_type *builtin = builtin_m2_type (gdbarch);
337
338  lai->string_char_type = builtin->builtin_char;
339  lai->primitive_type_vector
340    = GDBARCH_OBSTACK_CALLOC (gdbarch, nr_m2_primitive_types + 1,
341                              struct type *);
342
343  lai->primitive_type_vector [m2_primitive_type_char]
344    = builtin->builtin_char;
345  lai->primitive_type_vector [m2_primitive_type_int]
346    = builtin->builtin_int;
347  lai->primitive_type_vector [m2_primitive_type_card]
348    = builtin->builtin_card;
349  lai->primitive_type_vector [m2_primitive_type_real]
350    = builtin->builtin_real;
351  lai->primitive_type_vector [m2_primitive_type_bool]
352    = builtin->builtin_bool;
353
354  lai->bool_type_symbol = "BOOLEAN";
355  lai->bool_type_default = builtin->builtin_bool;
356}
357
358const struct exp_descriptor exp_descriptor_modula2 =
359{
360  print_subexp_standard,
361  operator_length_standard,
362  operator_check_standard,
363  op_name_standard,
364  dump_subexp_body_standard,
365  evaluate_subexp_modula2
366};
367
368const struct language_defn m2_language_defn =
369{
370  "modula-2",
371  language_m2,
372  range_check_on,
373  type_check_on,
374  case_sensitive_on,
375  array_row_major,
376  macro_expansion_no,
377  &exp_descriptor_modula2,
378  m2_parse,			/* parser */
379  m2_error,			/* parser error function */
380  null_post_parser,
381  m2_printchar,			/* Print character constant */
382  m2_printstr,			/* function to print string constant */
383  m2_emit_char,			/* Function to print a single character */
384  m2_print_type,		/* Print a type using appropriate syntax */
385  m2_print_typedef,		/* Print a typedef using appropriate syntax */
386  m2_val_print,			/* Print a value using appropriate syntax */
387  c_value_print,		/* Print a top-level value */
388  NULL,				/* Language specific skip_trampoline */
389  NULL,		                /* name_of_this */
390  basic_lookup_symbol_nonlocal,	/* lookup_symbol_nonlocal */
391  basic_lookup_transparent_type,/* lookup_transparent_type */
392  NULL,				/* Language specific symbol demangler */
393  NULL,				/* Language specific
394				   class_name_from_physname */
395  m2_op_print_tab,		/* expression operators for printing */
396  0,				/* arrays are first-class (not c-style) */
397  0,				/* String lower bound */
398  default_word_break_characters,
399  default_make_symbol_completion_list,
400  m2_language_arch_info,
401  default_print_array_index,
402  default_pass_by_reference,
403  default_get_string,
404  LANG_MAGIC
405};
406
407static void *
408build_m2_types (struct gdbarch *gdbarch)
409{
410  struct builtin_m2_type *builtin_m2_type
411    = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct builtin_m2_type);
412
413  /* Modula-2 "pervasive" types.  NOTE:  these can be redefined!!! */
414  builtin_m2_type->builtin_int
415    = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch), 0, "INTEGER");
416  builtin_m2_type->builtin_card
417    = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch), 1, "CARDINAL");
418  builtin_m2_type->builtin_real
419    = arch_float_type (gdbarch, gdbarch_float_bit (gdbarch), "REAL", NULL);
420  builtin_m2_type->builtin_char
421    = arch_character_type (gdbarch, TARGET_CHAR_BIT, 1, "CHAR");
422  builtin_m2_type->builtin_bool
423    = arch_boolean_type (gdbarch, gdbarch_int_bit (gdbarch), 1, "BOOLEAN");
424
425  return builtin_m2_type;
426}
427
428static struct gdbarch_data *m2_type_data;
429
430const struct builtin_m2_type *
431builtin_m2_type (struct gdbarch *gdbarch)
432{
433  return gdbarch_data (gdbarch, m2_type_data);
434}
435
436
437/* Initialization for Modula-2 */
438
439void
440_initialize_m2_language (void)
441{
442  m2_type_data = gdbarch_data_register_post_init (build_m2_types);
443
444  add_language (&m2_language_defn);
445}
446