xref: /dragonfly/contrib/gdb-7/gdb/m2-lang.c (revision 73610d44)
1 /* Modula 2 language support routines for GDB, the GNU debugger.
2 
3    Copyright (C) 1992-2013 Free Software Foundation, Inc.
4 
5    This file is part of GDB.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19 
20 #include "defs.h"
21 #include "symtab.h"
22 #include "gdbtypes.h"
23 #include "expression.h"
24 #include "parser-defs.h"
25 #include "language.h"
26 #include "m2-lang.h"
27 #include "c-lang.h"
28 #include "valprint.h"
29 
30 extern void _initialize_m2_language (void);
31 static void m2_printchar (int, struct type *, struct ui_file *);
32 static void m2_emit_char (int, struct type *, struct ui_file *, int);
33 
34 /* Print the character C on STREAM as part of the contents of a literal
35    string whose delimiter is QUOTER.  Note that that format for printing
36    characters and strings is language specific.
37    FIXME:  This is a copy of the same function from c-exp.y.  It should
38    be replaced with a true Modula version.  */
39 
40 static void
41 m2_emit_char (int c, struct type *type, struct ui_file *stream, int quoter)
42 {
43 
44   c &= 0xFF;			/* Avoid sign bit follies.  */
45 
46   if (PRINT_LITERAL_FORM (c))
47     {
48       if (c == '\\' || c == quoter)
49 	{
50 	  fputs_filtered ("\\", stream);
51 	}
52       fprintf_filtered (stream, "%c", c);
53     }
54   else
55     {
56       switch (c)
57 	{
58 	case '\n':
59 	  fputs_filtered ("\\n", stream);
60 	  break;
61 	case '\b':
62 	  fputs_filtered ("\\b", stream);
63 	  break;
64 	case '\t':
65 	  fputs_filtered ("\\t", stream);
66 	  break;
67 	case '\f':
68 	  fputs_filtered ("\\f", stream);
69 	  break;
70 	case '\r':
71 	  fputs_filtered ("\\r", stream);
72 	  break;
73 	case '\033':
74 	  fputs_filtered ("\\e", stream);
75 	  break;
76 	case '\007':
77 	  fputs_filtered ("\\a", stream);
78 	  break;
79 	default:
80 	  fprintf_filtered (stream, "\\%.3o", (unsigned int) c);
81 	  break;
82 	}
83     }
84 }
85 
86 /* FIXME:  This is a copy of the same function from c-exp.y.  It should
87    be replaced with a true Modula version.  */
88 
89 static void
90 m2_printchar (int c, struct type *type, struct ui_file *stream)
91 {
92   fputs_filtered ("'", stream);
93   LA_EMIT_CHAR (c, type, stream, '\'');
94   fputs_filtered ("'", stream);
95 }
96 
97 /* Print the character string STRING, printing at most LENGTH characters.
98    Printing stops early if the number hits print_max; repeat counts
99    are printed as appropriate.  Print ellipses at the end if we
100    had to stop before printing LENGTH characters, or if FORCE_ELLIPSES.
101    FIXME:  This is a copy of the same function from c-exp.y.  It should
102    be replaced with a true Modula version.  */
103 
104 static void
105 m2_printstr (struct ui_file *stream, struct type *type, const gdb_byte *string,
106 	     unsigned int length, const char *encoding, int force_ellipses,
107 	     const struct value_print_options *options)
108 {
109   unsigned int i;
110   unsigned int things_printed = 0;
111   int in_quotes = 0;
112   int need_comma = 0;
113 
114   if (length == 0)
115     {
116       fputs_filtered ("\"\"", gdb_stdout);
117       return;
118     }
119 
120   for (i = 0; i < length && things_printed < options->print_max; ++i)
121     {
122       /* Position of the character we are examining
123          to see whether it is repeated.  */
124       unsigned int rep1;
125       /* Number of repetitions we have detected so far.  */
126       unsigned int reps;
127 
128       QUIT;
129 
130       if (need_comma)
131 	{
132 	  fputs_filtered (", ", stream);
133 	  need_comma = 0;
134 	}
135 
136       rep1 = i + 1;
137       reps = 1;
138       while (rep1 < length && string[rep1] == string[i])
139 	{
140 	  ++rep1;
141 	  ++reps;
142 	}
143 
144       if (reps > options->repeat_count_threshold)
145 	{
146 	  if (in_quotes)
147 	    {
148 	      fputs_filtered ("\", ", stream);
149 	      in_quotes = 0;
150 	    }
151 	  m2_printchar (string[i], type, stream);
152 	  fprintf_filtered (stream, " <repeats %u times>", reps);
153 	  i = rep1 - 1;
154 	  things_printed += options->repeat_count_threshold;
155 	  need_comma = 1;
156 	}
157       else
158 	{
159 	  if (!in_quotes)
160 	    {
161 	      fputs_filtered ("\"", stream);
162 	      in_quotes = 1;
163 	    }
164 	  LA_EMIT_CHAR (string[i], type, stream, '"');
165 	  ++things_printed;
166 	}
167     }
168 
169   /* Terminate the quotes if necessary.  */
170   if (in_quotes)
171     fputs_filtered ("\"", stream);
172 
173   if (force_ellipses || i < length)
174     fputs_filtered ("...", stream);
175 }
176 
177 static struct value *
178 evaluate_subexp_modula2 (struct type *expect_type, struct expression *exp,
179 			 int *pos, enum noside noside)
180 {
181   enum exp_opcode op = exp->elts[*pos].opcode;
182   struct value *arg1;
183   struct value *arg2;
184   struct type *type;
185 
186   switch (op)
187     {
188     case UNOP_HIGH:
189       (*pos)++;
190       arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
191 
192       if (noside == EVAL_SKIP || noside == EVAL_AVOID_SIDE_EFFECTS)
193 	return arg1;
194       else
195 	{
196 	  arg1 = coerce_ref (arg1);
197 	  type = check_typedef (value_type (arg1));
198 
199 	  if (m2_is_unbounded_array (type))
200 	    {
201 	      struct value *temp = arg1;
202 
203 	      type = TYPE_FIELD_TYPE (type, 1);
204 	      /* i18n: Do not translate the "_m2_high" part!  */
205 	      arg1 = value_struct_elt (&temp, NULL, "_m2_high", NULL,
206 				       _("unbounded structure "
207 					 "missing _m2_high field"));
208 
209 	      if (value_type (arg1) != type)
210 		arg1 = value_cast (type, arg1);
211 	    }
212 	}
213       return arg1;
214 
215     case BINOP_SUBSCRIPT:
216       (*pos)++;
217       arg1 = evaluate_subexp_with_coercion (exp, pos, noside);
218       arg2 = evaluate_subexp_with_coercion (exp, pos, noside);
219       if (noside == EVAL_SKIP)
220 	goto nosideret;
221       /* If the user attempts to subscript something that is not an
222          array or pointer type (like a plain int variable for example),
223          then report this as an error.  */
224 
225       arg1 = coerce_ref (arg1);
226       type = check_typedef (value_type (arg1));
227 
228       if (m2_is_unbounded_array (type))
229 	{
230 	  struct value *temp = arg1;
231 	  type = TYPE_FIELD_TYPE (type, 0);
232 	  if (type == NULL || (TYPE_CODE (type) != TYPE_CODE_PTR))
233 	    {
234 	      warning (_("internal error: unbounded "
235 			 "array structure is unknown"));
236 	      return evaluate_subexp_standard (expect_type, exp, pos, noside);
237 	    }
238 	  /* i18n: Do not translate the "_m2_contents" part!  */
239 	  arg1 = value_struct_elt (&temp, NULL, "_m2_contents", NULL,
240 				   _("unbounded structure "
241 				     "missing _m2_contents field"));
242 
243 	  if (value_type (arg1) != type)
244 	    arg1 = value_cast (type, arg1);
245 
246 	  check_typedef (value_type (arg1));
247 	  return value_ind (value_ptradd (arg1, value_as_long (arg2)));
248 	}
249       else
250 	if (TYPE_CODE (type) != TYPE_CODE_ARRAY)
251 	  {
252 	    if (TYPE_NAME (type))
253 	      error (_("cannot subscript something of type `%s'"),
254 		     TYPE_NAME (type));
255 	    else
256 	      error (_("cannot subscript requested type"));
257 	  }
258 
259       if (noside == EVAL_AVOID_SIDE_EFFECTS)
260 	return value_zero (TYPE_TARGET_TYPE (type), VALUE_LVAL (arg1));
261       else
262 	return value_subscript (arg1, value_as_long (arg2));
263 
264     default:
265       return evaluate_subexp_standard (expect_type, exp, pos, noside);
266     }
267 
268  nosideret:
269   return value_from_longest (builtin_type (exp->gdbarch)->builtin_int, 1);
270 }
271 
272 
273 /* Table of operators and their precedences for printing expressions.  */
274 
275 static const struct op_print m2_op_print_tab[] =
276 {
277   {"+", BINOP_ADD, PREC_ADD, 0},
278   {"+", UNOP_PLUS, PREC_PREFIX, 0},
279   {"-", BINOP_SUB, PREC_ADD, 0},
280   {"-", UNOP_NEG, PREC_PREFIX, 0},
281   {"*", BINOP_MUL, PREC_MUL, 0},
282   {"/", BINOP_DIV, PREC_MUL, 0},
283   {"DIV", BINOP_INTDIV, PREC_MUL, 0},
284   {"MOD", BINOP_REM, PREC_MUL, 0},
285   {":=", BINOP_ASSIGN, PREC_ASSIGN, 1},
286   {"OR", BINOP_LOGICAL_OR, PREC_LOGICAL_OR, 0},
287   {"AND", BINOP_LOGICAL_AND, PREC_LOGICAL_AND, 0},
288   {"NOT", UNOP_LOGICAL_NOT, PREC_PREFIX, 0},
289   {"=", BINOP_EQUAL, PREC_EQUAL, 0},
290   {"<>", BINOP_NOTEQUAL, PREC_EQUAL, 0},
291   {"<=", BINOP_LEQ, PREC_ORDER, 0},
292   {">=", BINOP_GEQ, PREC_ORDER, 0},
293   {">", BINOP_GTR, PREC_ORDER, 0},
294   {"<", BINOP_LESS, PREC_ORDER, 0},
295   {"^", UNOP_IND, PREC_PREFIX, 0},
296   {"@", BINOP_REPEAT, PREC_REPEAT, 0},
297   {"CAP", UNOP_CAP, PREC_BUILTIN_FUNCTION, 0},
298   {"CHR", UNOP_CHR, PREC_BUILTIN_FUNCTION, 0},
299   {"ORD", UNOP_ORD, PREC_BUILTIN_FUNCTION, 0},
300   {"FLOAT", UNOP_FLOAT, PREC_BUILTIN_FUNCTION, 0},
301   {"HIGH", UNOP_HIGH, PREC_BUILTIN_FUNCTION, 0},
302   {"MAX", UNOP_MAX, PREC_BUILTIN_FUNCTION, 0},
303   {"MIN", UNOP_MIN, PREC_BUILTIN_FUNCTION, 0},
304   {"ODD", UNOP_ODD, PREC_BUILTIN_FUNCTION, 0},
305   {"TRUNC", UNOP_TRUNC, PREC_BUILTIN_FUNCTION, 0},
306   {NULL, 0, 0, 0}
307 };
308 
309 /* The built-in types of Modula-2.  */
310 
311 enum m2_primitive_types {
312   m2_primitive_type_char,
313   m2_primitive_type_int,
314   m2_primitive_type_card,
315   m2_primitive_type_real,
316   m2_primitive_type_bool,
317   nr_m2_primitive_types
318 };
319 
320 static void
321 m2_language_arch_info (struct gdbarch *gdbarch,
322 		       struct language_arch_info *lai)
323 {
324   const struct builtin_m2_type *builtin = builtin_m2_type (gdbarch);
325 
326   lai->string_char_type = builtin->builtin_char;
327   lai->primitive_type_vector
328     = GDBARCH_OBSTACK_CALLOC (gdbarch, nr_m2_primitive_types + 1,
329                               struct type *);
330 
331   lai->primitive_type_vector [m2_primitive_type_char]
332     = builtin->builtin_char;
333   lai->primitive_type_vector [m2_primitive_type_int]
334     = builtin->builtin_int;
335   lai->primitive_type_vector [m2_primitive_type_card]
336     = builtin->builtin_card;
337   lai->primitive_type_vector [m2_primitive_type_real]
338     = builtin->builtin_real;
339   lai->primitive_type_vector [m2_primitive_type_bool]
340     = builtin->builtin_bool;
341 
342   lai->bool_type_symbol = "BOOLEAN";
343   lai->bool_type_default = builtin->builtin_bool;
344 }
345 
346 const struct exp_descriptor exp_descriptor_modula2 =
347 {
348   print_subexp_standard,
349   operator_length_standard,
350   operator_check_standard,
351   op_name_standard,
352   dump_subexp_body_standard,
353   evaluate_subexp_modula2
354 };
355 
356 const struct language_defn m2_language_defn =
357 {
358   "modula-2",
359   language_m2,
360   range_check_on,
361   case_sensitive_on,
362   array_row_major,
363   macro_expansion_no,
364   &exp_descriptor_modula2,
365   m2_parse,			/* parser */
366   m2_error,			/* parser error function */
367   null_post_parser,
368   m2_printchar,			/* Print character constant */
369   m2_printstr,			/* function to print string constant */
370   m2_emit_char,			/* Function to print a single character */
371   m2_print_type,		/* Print a type using appropriate syntax */
372   m2_print_typedef,		/* Print a typedef using appropriate syntax */
373   m2_val_print,			/* Print a value using appropriate syntax */
374   c_value_print,		/* Print a top-level value */
375   default_read_var_value,	/* la_read_var_value */
376   NULL,				/* Language specific skip_trampoline */
377   NULL,		                /* name_of_this */
378   basic_lookup_symbol_nonlocal,	/* lookup_symbol_nonlocal */
379   basic_lookup_transparent_type,/* lookup_transparent_type */
380   NULL,				/* Language specific symbol demangler */
381   NULL,				/* Language specific
382 				   class_name_from_physname */
383   m2_op_print_tab,		/* expression operators for printing */
384   0,				/* arrays are first-class (not c-style) */
385   0,				/* String lower bound */
386   default_word_break_characters,
387   default_make_symbol_completion_list,
388   m2_language_arch_info,
389   default_print_array_index,
390   default_pass_by_reference,
391   default_get_string,
392   NULL,				/* la_get_symbol_name_cmp */
393   iterate_over_symbols,
394   LANG_MAGIC
395 };
396 
397 static void *
398 build_m2_types (struct gdbarch *gdbarch)
399 {
400   struct builtin_m2_type *builtin_m2_type
401     = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct builtin_m2_type);
402 
403   /* Modula-2 "pervasive" types.  NOTE:  these can be redefined!!! */
404   builtin_m2_type->builtin_int
405     = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch), 0, "INTEGER");
406   builtin_m2_type->builtin_card
407     = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch), 1, "CARDINAL");
408   builtin_m2_type->builtin_real
409     = arch_float_type (gdbarch, gdbarch_float_bit (gdbarch), "REAL", NULL);
410   builtin_m2_type->builtin_char
411     = arch_character_type (gdbarch, TARGET_CHAR_BIT, 1, "CHAR");
412   builtin_m2_type->builtin_bool
413     = arch_boolean_type (gdbarch, gdbarch_int_bit (gdbarch), 1, "BOOLEAN");
414 
415   return builtin_m2_type;
416 }
417 
418 static struct gdbarch_data *m2_type_data;
419 
420 const struct builtin_m2_type *
421 builtin_m2_type (struct gdbarch *gdbarch)
422 {
423   return gdbarch_data (gdbarch, m2_type_data);
424 }
425 
426 
427 /* Initialization for Modula-2 */
428 
429 void
430 _initialize_m2_language (void)
431 {
432   m2_type_data = gdbarch_data_register_post_init (build_m2_types);
433 
434   add_language (&m2_language_defn);
435 }
436