1 /* Pascal language support routines for GDB, the GNU debugger.
2
3 Copyright (C) 2000-2013 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 /* This file is derived from c-lang.c */
21
22 #include "defs.h"
23 #include "gdb_string.h"
24 #include "symtab.h"
25 #include "gdbtypes.h"
26 #include "expression.h"
27 #include "parser-defs.h"
28 #include "language.h"
29 #include "p-lang.h"
30 #include "valprint.h"
31 #include "value.h"
32 #include <ctype.h>
33
34 extern void _initialize_pascal_language (void);
35
36
37 /* All GPC versions until now (2007-09-27) also define a symbol called
38 '_p_initialize'. Check for the presence of this symbol first. */
39 static const char GPC_P_INITIALIZE[] = "_p_initialize";
40
41 /* The name of the symbol that GPC uses as the name of the main
42 procedure (since version 20050212). */
43 static const char GPC_MAIN_PROGRAM_NAME_1[] = "_p__M0_main_program";
44
45 /* Older versions of GPC (versions older than 20050212) were using
46 a different name for the main procedure. */
47 static const char GPC_MAIN_PROGRAM_NAME_2[] = "pascal_main_program";
48
49 /* Function returning the special symbol name used
50 by GPC for the main procedure in the main program
51 if it is found in minimal symbol list.
52 This function tries to find minimal symbols generated by GPC
53 so that it finds the even if the program was compiled
54 without debugging information.
55 According to information supplied by Waldeck Hebisch,
56 this should work for all versions posterior to June 2000. */
57
58 const char *
pascal_main_name(void)59 pascal_main_name (void)
60 {
61 struct minimal_symbol *msym;
62
63 msym = lookup_minimal_symbol (GPC_P_INITIALIZE, NULL, NULL);
64
65 /* If '_p_initialize' was not found, the main program is likely not
66 written in Pascal. */
67 if (msym == NULL)
68 return NULL;
69
70 msym = lookup_minimal_symbol (GPC_MAIN_PROGRAM_NAME_1, NULL, NULL);
71 if (msym != NULL)
72 {
73 return GPC_MAIN_PROGRAM_NAME_1;
74 }
75
76 msym = lookup_minimal_symbol (GPC_MAIN_PROGRAM_NAME_2, NULL, NULL);
77 if (msym != NULL)
78 {
79 return GPC_MAIN_PROGRAM_NAME_2;
80 }
81
82 /* No known entry procedure found, the main program is probably
83 not compiled with GPC. */
84 return NULL;
85 }
86
87 /* Determines if type TYPE is a pascal string type.
88 Returns a positive value if the type is a known pascal string type.
89 This function is used by p-valprint.c code to allow better string display.
90 If it is a pascal string type, then it also sets info needed
91 to get the length and the data of the string
92 length_pos, length_size and string_pos are given in bytes.
93 char_size gives the element size in bytes.
94 FIXME: if the position or the size of these fields
95 are not multiple of TARGET_CHAR_BIT then the results are wrong
96 but this does not happen for Free Pascal nor for GPC. */
97 int
is_pascal_string_type(struct type * type,int * length_pos,int * length_size,int * string_pos,struct type ** char_type,const char ** arrayname)98 is_pascal_string_type (struct type *type,int *length_pos,
99 int *length_size, int *string_pos,
100 struct type **char_type,
101 const char **arrayname)
102 {
103 if (type != NULL && TYPE_CODE (type) == TYPE_CODE_STRUCT)
104 {
105 /* Old Borland type pascal strings from Free Pascal Compiler. */
106 /* Two fields: length and st. */
107 if (TYPE_NFIELDS (type) == 2
108 && TYPE_FIELD_NAME (type, 0)
109 && strcmp (TYPE_FIELD_NAME (type, 0), "length") == 0
110 && TYPE_FIELD_NAME (type, 1)
111 && strcmp (TYPE_FIELD_NAME (type, 1), "st") == 0)
112 {
113 if (length_pos)
114 *length_pos = TYPE_FIELD_BITPOS (type, 0) / TARGET_CHAR_BIT;
115 if (length_size)
116 *length_size = TYPE_LENGTH (TYPE_FIELD_TYPE (type, 0));
117 if (string_pos)
118 *string_pos = TYPE_FIELD_BITPOS (type, 1) / TARGET_CHAR_BIT;
119 if (char_type)
120 *char_type = TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (type, 1));
121 if (arrayname)
122 *arrayname = TYPE_FIELD_NAME (type, 1);
123 return 2;
124 };
125 /* GNU pascal strings. */
126 /* Three fields: Capacity, length and schema$ or _p_schema. */
127 if (TYPE_NFIELDS (type) == 3
128 && TYPE_FIELD_NAME (type, 0)
129 && strcmp (TYPE_FIELD_NAME (type, 0), "Capacity") == 0
130 && TYPE_FIELD_NAME (type, 1)
131 && strcmp (TYPE_FIELD_NAME (type, 1), "length") == 0)
132 {
133 if (length_pos)
134 *length_pos = TYPE_FIELD_BITPOS (type, 1) / TARGET_CHAR_BIT;
135 if (length_size)
136 *length_size = TYPE_LENGTH (TYPE_FIELD_TYPE (type, 1));
137 if (string_pos)
138 *string_pos = TYPE_FIELD_BITPOS (type, 2) / TARGET_CHAR_BIT;
139 /* FIXME: how can I detect wide chars in GPC ?? */
140 if (char_type)
141 {
142 *char_type = TYPE_TARGET_TYPE (TYPE_FIELD_TYPE (type, 2));
143
144 if (TYPE_CODE (*char_type) == TYPE_CODE_ARRAY)
145 *char_type = TYPE_TARGET_TYPE (*char_type);
146 }
147 if (arrayname)
148 *arrayname = TYPE_FIELD_NAME (type, 2);
149 return 3;
150 };
151 }
152 return 0;
153 }
154
155 static void pascal_one_char (int, struct ui_file *, int *);
156
157 /* Print the character C on STREAM as part of the contents of a literal
158 string.
159 In_quotes is reset to 0 if a char is written with #4 notation. */
160
161 static void
pascal_one_char(int c,struct ui_file * stream,int * in_quotes)162 pascal_one_char (int c, struct ui_file *stream, int *in_quotes)
163 {
164 if (c == '\'' || ((unsigned int) c <= 0xff && (PRINT_LITERAL_FORM (c))))
165 {
166 if (!(*in_quotes))
167 fputs_filtered ("'", stream);
168 *in_quotes = 1;
169 if (c == '\'')
170 {
171 fputs_filtered ("''", stream);
172 }
173 else
174 fprintf_filtered (stream, "%c", c);
175 }
176 else
177 {
178 if (*in_quotes)
179 fputs_filtered ("'", stream);
180 *in_quotes = 0;
181 fprintf_filtered (stream, "#%d", (unsigned int) c);
182 }
183 }
184
185 static void pascal_emit_char (int c, struct type *type,
186 struct ui_file *stream, int quoter);
187
188 /* Print the character C on STREAM as part of the contents of a literal
189 string whose delimiter is QUOTER. Note that that format for printing
190 characters and strings is language specific. */
191
192 static void
pascal_emit_char(int c,struct type * type,struct ui_file * stream,int quoter)193 pascal_emit_char (int c, struct type *type, struct ui_file *stream, int quoter)
194 {
195 int in_quotes = 0;
196
197 pascal_one_char (c, stream, &in_quotes);
198 if (in_quotes)
199 fputs_filtered ("'", stream);
200 }
201
202 void
pascal_printchar(int c,struct type * type,struct ui_file * stream)203 pascal_printchar (int c, struct type *type, struct ui_file *stream)
204 {
205 int in_quotes = 0;
206
207 pascal_one_char (c, stream, &in_quotes);
208 if (in_quotes)
209 fputs_filtered ("'", stream);
210 }
211
212 /* Print the character string STRING, printing at most LENGTH characters.
213 Printing stops early if the number hits print_max; repeat counts
214 are printed as appropriate. Print ellipses at the end if we
215 had to stop before printing LENGTH characters, or if FORCE_ELLIPSES. */
216
217 void
pascal_printstr(struct ui_file * stream,struct type * type,const gdb_byte * string,unsigned int length,const char * encoding,int force_ellipses,const struct value_print_options * options)218 pascal_printstr (struct ui_file *stream, struct type *type,
219 const gdb_byte *string, unsigned int length,
220 const char *encoding, int force_ellipses,
221 const struct value_print_options *options)
222 {
223 enum bfd_endian byte_order = gdbarch_byte_order (get_type_arch (type));
224 unsigned int i;
225 unsigned int things_printed = 0;
226 int in_quotes = 0;
227 int need_comma = 0;
228 int width;
229
230 /* Preserve TYPE's original type, just set its LENGTH. */
231 check_typedef (type);
232 width = TYPE_LENGTH (type);
233
234 /* If the string was not truncated due to `set print elements', and
235 the last byte of it is a null, we don't print that, in traditional C
236 style. */
237 if ((!force_ellipses) && length > 0
238 && extract_unsigned_integer (string + (length - 1) * width, width,
239 byte_order) == 0)
240 length--;
241
242 if (length == 0)
243 {
244 fputs_filtered ("''", stream);
245 return;
246 }
247
248 for (i = 0; i < length && things_printed < options->print_max; ++i)
249 {
250 /* Position of the character we are examining
251 to see whether it is repeated. */
252 unsigned int rep1;
253 /* Number of repetitions we have detected so far. */
254 unsigned int reps;
255 unsigned long int current_char;
256
257 QUIT;
258
259 if (need_comma)
260 {
261 fputs_filtered (", ", stream);
262 need_comma = 0;
263 }
264
265 current_char = extract_unsigned_integer (string + i * width, width,
266 byte_order);
267
268 rep1 = i + 1;
269 reps = 1;
270 while (rep1 < length
271 && extract_unsigned_integer (string + rep1 * width, width,
272 byte_order) == current_char)
273 {
274 ++rep1;
275 ++reps;
276 }
277
278 if (reps > options->repeat_count_threshold)
279 {
280 if (in_quotes)
281 {
282 fputs_filtered ("', ", stream);
283 in_quotes = 0;
284 }
285 pascal_printchar (current_char, type, stream);
286 fprintf_filtered (stream, " <repeats %u times>", reps);
287 i = rep1 - 1;
288 things_printed += options->repeat_count_threshold;
289 need_comma = 1;
290 }
291 else
292 {
293 if ((!in_quotes) && (PRINT_LITERAL_FORM (current_char)))
294 {
295 fputs_filtered ("'", stream);
296 in_quotes = 1;
297 }
298 pascal_one_char (current_char, stream, &in_quotes);
299 ++things_printed;
300 }
301 }
302
303 /* Terminate the quotes if necessary. */
304 if (in_quotes)
305 fputs_filtered ("'", stream);
306
307 if (force_ellipses || i < length)
308 fputs_filtered ("...", stream);
309 }
310
311
312 /* Table mapping opcodes into strings for printing operators
313 and precedences of the operators. */
314
315 const struct op_print pascal_op_print_tab[] =
316 {
317 {",", BINOP_COMMA, PREC_COMMA, 0},
318 {":=", BINOP_ASSIGN, PREC_ASSIGN, 1},
319 {"or", BINOP_BITWISE_IOR, PREC_BITWISE_IOR, 0},
320 {"xor", BINOP_BITWISE_XOR, PREC_BITWISE_XOR, 0},
321 {"and", BINOP_BITWISE_AND, PREC_BITWISE_AND, 0},
322 {"=", BINOP_EQUAL, PREC_EQUAL, 0},
323 {"<>", BINOP_NOTEQUAL, PREC_EQUAL, 0},
324 {"<=", BINOP_LEQ, PREC_ORDER, 0},
325 {">=", BINOP_GEQ, PREC_ORDER, 0},
326 {">", BINOP_GTR, PREC_ORDER, 0},
327 {"<", BINOP_LESS, PREC_ORDER, 0},
328 {"shr", BINOP_RSH, PREC_SHIFT, 0},
329 {"shl", BINOP_LSH, PREC_SHIFT, 0},
330 {"+", BINOP_ADD, PREC_ADD, 0},
331 {"-", BINOP_SUB, PREC_ADD, 0},
332 {"*", BINOP_MUL, PREC_MUL, 0},
333 {"/", BINOP_DIV, PREC_MUL, 0},
334 {"div", BINOP_INTDIV, PREC_MUL, 0},
335 {"mod", BINOP_REM, PREC_MUL, 0},
336 {"@", BINOP_REPEAT, PREC_REPEAT, 0},
337 {"-", UNOP_NEG, PREC_PREFIX, 0},
338 {"not", UNOP_LOGICAL_NOT, PREC_PREFIX, 0},
339 {"^", UNOP_IND, PREC_SUFFIX, 1},
340 {"@", UNOP_ADDR, PREC_PREFIX, 0},
341 {"sizeof", UNOP_SIZEOF, PREC_PREFIX, 0},
342 {NULL, 0, 0, 0}
343 };
344
345 enum pascal_primitive_types {
346 pascal_primitive_type_int,
347 pascal_primitive_type_long,
348 pascal_primitive_type_short,
349 pascal_primitive_type_char,
350 pascal_primitive_type_float,
351 pascal_primitive_type_double,
352 pascal_primitive_type_void,
353 pascal_primitive_type_long_long,
354 pascal_primitive_type_signed_char,
355 pascal_primitive_type_unsigned_char,
356 pascal_primitive_type_unsigned_short,
357 pascal_primitive_type_unsigned_int,
358 pascal_primitive_type_unsigned_long,
359 pascal_primitive_type_unsigned_long_long,
360 pascal_primitive_type_long_double,
361 pascal_primitive_type_complex,
362 pascal_primitive_type_double_complex,
363 nr_pascal_primitive_types
364 };
365
366 static void
pascal_language_arch_info(struct gdbarch * gdbarch,struct language_arch_info * lai)367 pascal_language_arch_info (struct gdbarch *gdbarch,
368 struct language_arch_info *lai)
369 {
370 const struct builtin_type *builtin = builtin_type (gdbarch);
371
372 lai->string_char_type = builtin->builtin_char;
373 lai->primitive_type_vector
374 = GDBARCH_OBSTACK_CALLOC (gdbarch, nr_pascal_primitive_types + 1,
375 struct type *);
376 lai->primitive_type_vector [pascal_primitive_type_int]
377 = builtin->builtin_int;
378 lai->primitive_type_vector [pascal_primitive_type_long]
379 = builtin->builtin_long;
380 lai->primitive_type_vector [pascal_primitive_type_short]
381 = builtin->builtin_short;
382 lai->primitive_type_vector [pascal_primitive_type_char]
383 = builtin->builtin_char;
384 lai->primitive_type_vector [pascal_primitive_type_float]
385 = builtin->builtin_float;
386 lai->primitive_type_vector [pascal_primitive_type_double]
387 = builtin->builtin_double;
388 lai->primitive_type_vector [pascal_primitive_type_void]
389 = builtin->builtin_void;
390 lai->primitive_type_vector [pascal_primitive_type_long_long]
391 = builtin->builtin_long_long;
392 lai->primitive_type_vector [pascal_primitive_type_signed_char]
393 = builtin->builtin_signed_char;
394 lai->primitive_type_vector [pascal_primitive_type_unsigned_char]
395 = builtin->builtin_unsigned_char;
396 lai->primitive_type_vector [pascal_primitive_type_unsigned_short]
397 = builtin->builtin_unsigned_short;
398 lai->primitive_type_vector [pascal_primitive_type_unsigned_int]
399 = builtin->builtin_unsigned_int;
400 lai->primitive_type_vector [pascal_primitive_type_unsigned_long]
401 = builtin->builtin_unsigned_long;
402 lai->primitive_type_vector [pascal_primitive_type_unsigned_long_long]
403 = builtin->builtin_unsigned_long_long;
404 lai->primitive_type_vector [pascal_primitive_type_long_double]
405 = builtin->builtin_long_double;
406 lai->primitive_type_vector [pascal_primitive_type_complex]
407 = builtin->builtin_complex;
408 lai->primitive_type_vector [pascal_primitive_type_double_complex]
409 = builtin->builtin_double_complex;
410
411 lai->bool_type_symbol = "boolean";
412 lai->bool_type_default = builtin->builtin_bool;
413 }
414
415 const struct language_defn pascal_language_defn =
416 {
417 "pascal", /* Language name */
418 language_pascal,
419 range_check_on,
420 case_sensitive_on,
421 array_row_major,
422 macro_expansion_no,
423 &exp_descriptor_standard,
424 pascal_parse,
425 pascal_error,
426 null_post_parser,
427 pascal_printchar, /* Print a character constant */
428 pascal_printstr, /* Function to print string constant */
429 pascal_emit_char, /* Print a single char */
430 pascal_print_type, /* Print a type using appropriate syntax */
431 pascal_print_typedef, /* Print a typedef using appropriate syntax */
432 pascal_val_print, /* Print a value using appropriate syntax */
433 pascal_value_print, /* Print a top-level value */
434 default_read_var_value, /* la_read_var_value */
435 NULL, /* Language specific skip_trampoline */
436 "this", /* name_of_this */
437 basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */
438 basic_lookup_transparent_type,/* lookup_transparent_type */
439 NULL, /* Language specific symbol demangler */
440 NULL, /* Language specific class_name_from_physname */
441 pascal_op_print_tab, /* expression operators for printing */
442 1, /* c-style arrays */
443 0, /* String lower bound */
444 default_word_break_characters,
445 default_make_symbol_completion_list,
446 pascal_language_arch_info,
447 default_print_array_index,
448 default_pass_by_reference,
449 default_get_string,
450 NULL, /* la_get_symbol_name_cmp */
451 iterate_over_symbols,
452 LANG_MAGIC
453 };
454
455 void
_initialize_pascal_language(void)456 _initialize_pascal_language (void)
457 {
458 add_language (&pascal_language_defn);
459 }
460