xref: /dragonfly/contrib/gdb-7/gdb/p-lang.c (revision ef5ccd6c)
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