1/* Scheme/Guile language support routines for GDB, the GNU debugger. 2 3 Copyright (C) 1995, 1996, 1998, 2000, 2001, 2002, 2003, 2004, 2005, 2007 Free 4 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 "value.h" 28#include "c-lang.h" 29#include "scm-lang.h" 30#include "scm-tags.h" 31#include "source.h" 32#include "gdb_string.h" 33#include "gdbcore.h" 34#include "infcall.h" 35 36extern void _initialize_scheme_language (void); 37static struct value *evaluate_subexp_scm (struct type *, struct expression *, 38 int *, enum noside); 39static struct value *scm_lookup_name (char *); 40static int in_eval_c (void); 41 42struct type *builtin_type_scm; 43 44void 45scm_printchar (int c, struct ui_file *stream) 46{ 47 fprintf_filtered (stream, "#\\%c", c); 48} 49 50static void 51scm_printstr (struct ui_file *stream, const gdb_byte *string, 52 unsigned int length, int width, int force_ellipses) 53{ 54 fprintf_filtered (stream, "\"%s\"", string); 55} 56 57int 58is_scmvalue_type (struct type *type) 59{ 60 if (TYPE_NAME (type) && strcmp (TYPE_NAME (type), "SCM") == 0) 61 { 62 return 1; 63 } 64 return 0; 65} 66 67/* Get the INDEX'th SCM value, assuming SVALUE is the address 68 of the 0'th one. */ 69 70LONGEST 71scm_get_field (LONGEST svalue, int index) 72{ 73 gdb_byte buffer[20]; 74 read_memory (SCM2PTR (svalue) + index * TYPE_LENGTH (builtin_type_scm), 75 buffer, TYPE_LENGTH (builtin_type_scm)); 76 return extract_signed_integer (buffer, TYPE_LENGTH (builtin_type_scm)); 77} 78 79/* Unpack a value of type TYPE in buffer VALADDR as an integer 80 (if CONTEXT == TYPE_CODE_IN), a pointer (CONTEXT == TYPE_CODE_PTR), 81 or Boolean (CONTEXT == TYPE_CODE_BOOL). */ 82 83LONGEST 84scm_unpack (struct type *type, const gdb_byte *valaddr, enum type_code context) 85{ 86 if (is_scmvalue_type (type)) 87 { 88 LONGEST svalue = extract_signed_integer (valaddr, TYPE_LENGTH (type)); 89 if (context == TYPE_CODE_BOOL) 90 { 91 if (svalue == SCM_BOOL_F) 92 return 0; 93 else 94 return 1; 95 } 96 switch (7 & (int) svalue) 97 { 98 case 2: 99 case 6: /* fixnum */ 100 return svalue >> 2; 101 case 4: /* other immediate value */ 102 if (SCM_ICHRP (svalue)) /* character */ 103 return SCM_ICHR (svalue); 104 else if (SCM_IFLAGP (svalue)) 105 { 106 switch ((int) svalue) 107 { 108#ifndef SICP 109 case SCM_EOL: 110#endif 111 case SCM_BOOL_F: 112 return 0; 113 case SCM_BOOL_T: 114 return 1; 115 } 116 } 117 error (_("Value can't be converted to integer.")); 118 default: 119 return svalue; 120 } 121 } 122 else 123 return unpack_long (type, valaddr); 124} 125 126/* True if we're correctly in Guile's eval.c (the evaluator and apply). */ 127 128static int 129in_eval_c (void) 130{ 131 struct symtab_and_line cursal = get_current_source_symtab_and_line (); 132 133 if (cursal.symtab && cursal.symtab->filename) 134 { 135 char *filename = cursal.symtab->filename; 136 int len = strlen (filename); 137 if (len >= 6 && strcmp (filename + len - 6, "eval.c") == 0) 138 return 1; 139 } 140 return 0; 141} 142 143/* Lookup a value for the variable named STR. 144 First lookup in Scheme context (using the scm_lookup_cstr inferior 145 function), then try lookup_symbol for compiled variables. */ 146 147static struct value * 148scm_lookup_name (char *str) 149{ 150 struct value *args[3]; 151 int len = strlen (str); 152 struct value *func; 153 struct value *val; 154 struct symbol *sym; 155 args[0] = value_allocate_space_in_inferior (len); 156 args[1] = value_from_longest (builtin_type_int, len); 157 write_memory (value_as_long (args[0]), (gdb_byte *) str, len); 158 159 if (in_eval_c () 160 && (sym = lookup_symbol ("env", 161 expression_context_block, 162 VAR_DOMAIN, (int *) NULL, 163 (struct symtab **) NULL)) != NULL) 164 args[2] = value_of_variable (sym, expression_context_block); 165 else 166 /* FIXME in this case, we should try lookup_symbol first */ 167 args[2] = value_from_longest (builtin_type_scm, SCM_EOL); 168 169 func = find_function_in_inferior ("scm_lookup_cstr"); 170 val = call_function_by_hand (func, 3, args); 171 if (!value_logical_not (val)) 172 return value_ind (val); 173 174 sym = lookup_symbol (str, 175 expression_context_block, 176 VAR_DOMAIN, (int *) NULL, 177 (struct symtab **) NULL); 178 if (sym) 179 return value_of_variable (sym, NULL); 180 error (_("No symbol \"%s\" in current context."), str); 181} 182 183struct value * 184scm_evaluate_string (char *str, int len) 185{ 186 struct value *func; 187 struct value *addr = value_allocate_space_in_inferior (len + 1); 188 LONGEST iaddr = value_as_long (addr); 189 write_memory (iaddr, (gdb_byte *) str, len); 190 /* FIXME - should find and pass env */ 191 write_memory (iaddr + len, (gdb_byte *) "", 1); 192 func = find_function_in_inferior ("scm_evstr"); 193 return call_function_by_hand (func, 1, &addr); 194} 195 196static struct value * 197evaluate_exp (struct type *expect_type, struct expression *exp, 198 int *pos, enum noside noside) 199{ 200 enum exp_opcode op = exp->elts[*pos].opcode; 201 int len, pc; 202 char *str; 203 switch (op) 204 { 205 case OP_NAME: 206 pc = (*pos)++; 207 len = longest_to_int (exp->elts[pc + 1].longconst); 208 (*pos) += 3 + BYTES_TO_EXP_ELEM (len + 1); 209 if (noside == EVAL_SKIP) 210 goto nosideret; 211 str = &exp->elts[pc + 2].string; 212 return scm_lookup_name (str); 213 case OP_STRING: 214 pc = (*pos)++; 215 len = longest_to_int (exp->elts[pc + 1].longconst); 216 (*pos) += 3 + BYTES_TO_EXP_ELEM (len + 1); 217 if (noside == EVAL_SKIP) 218 goto nosideret; 219 str = &exp->elts[pc + 2].string; 220 return scm_evaluate_string (str, len); 221 default:; 222 } 223 return evaluate_subexp_standard (expect_type, exp, pos, noside); 224nosideret: 225 return value_from_longest (builtin_type_long, (LONGEST) 1); 226} 227 228const struct exp_descriptor exp_descriptor_scm = 229{ 230 print_subexp_standard, 231 operator_length_standard, 232 op_name_standard, 233 dump_subexp_body_standard, 234 evaluate_exp 235}; 236 237const struct language_defn scm_language_defn = 238{ 239 "scheme", /* Language name */ 240 language_scm, 241 NULL, 242 range_check_off, 243 type_check_off, 244 case_sensitive_off, 245 array_row_major, 246 &exp_descriptor_scm, 247 scm_parse, 248 c_error, 249 null_post_parser, 250 scm_printchar, /* Print a character constant */ 251 scm_printstr, /* Function to print string constant */ 252 NULL, /* Function to print a single character */ 253 NULL, /* Create fundamental type in this language */ 254 c_print_type, /* Print a type using appropriate syntax */ 255 scm_val_print, /* Print a value using appropriate syntax */ 256 scm_value_print, /* Print a top-level value */ 257 NULL, /* Language specific skip_trampoline */ 258 value_of_this, /* value_of_this */ 259 basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */ 260 basic_lookup_transparent_type,/* lookup_transparent_type */ 261 NULL, /* Language specific symbol demangler */ 262 NULL, /* Language specific class_name_from_physname */ 263 NULL, /* expression operators for printing */ 264 1, /* c-style arrays */ 265 0, /* String lower bound */ 266 NULL, 267 default_word_break_characters, 268 c_language_arch_info, 269 default_print_array_index, 270 LANG_MAGIC 271}; 272 273void 274_initialize_scheme_language (void) 275{ 276 add_language (&scm_language_defn); 277 builtin_type_scm = 278 init_type (TYPE_CODE_INT, 279 gdbarch_long_bit (current_gdbarch) / TARGET_CHAR_BIT, 280 0, "SCM", (struct objfile *) NULL); 281} 282