1 /* Scheme/Guile language support routines for GDB, the GNU debugger. 2 3 Copyright 1995, 1996, 1998, 2000, 2001, 2002, 2003, 2004 Free Software 4 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 2 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, write to the Free Software 20 Foundation, Inc., 59 Temple Place - Suite 330, 21 Boston, MA 02111-1307, USA. */ 22 23 #include "defs.h" 24 #include "symtab.h" 25 #include "gdbtypes.h" 26 #include "expression.h" 27 #include "parser-defs.h" 28 #include "language.h" 29 #include "value.h" 30 #include "c-lang.h" 31 #include "scm-lang.h" 32 #include "scm-tags.h" 33 #include "source.h" 34 #include "gdb_string.h" 35 #include "gdbcore.h" 36 #include "infcall.h" 37 38 extern void _initialize_scheme_language (void); 39 static struct value *evaluate_subexp_scm (struct type *, struct expression *, 40 int *, enum noside); 41 static struct value *scm_lookup_name (char *); 42 static int in_eval_c (void); 43 static void scm_printstr (struct ui_file * stream, char *string, 44 unsigned int length, int width, 45 int force_ellipses); 46 47 struct type *builtin_type_scm; 48 49 void 50 scm_printchar (int c, struct ui_file *stream) 51 { 52 fprintf_filtered (stream, "#\\%c", c); 53 } 54 55 static void 56 scm_printstr (struct ui_file *stream, char *string, unsigned int length, 57 int width, int force_ellipses) 58 { 59 fprintf_filtered (stream, "\"%s\"", string); 60 } 61 62 int 63 is_scmvalue_type (struct type *type) 64 { 65 if (TYPE_CODE (type) == TYPE_CODE_INT 66 && TYPE_NAME (type) && strcmp (TYPE_NAME (type), "SCM") == 0) 67 { 68 return 1; 69 } 70 return 0; 71 } 72 73 /* Get the INDEX'th SCM value, assuming SVALUE is the address 74 of the 0'th one. */ 75 76 LONGEST 77 scm_get_field (LONGEST svalue, int index) 78 { 79 char buffer[20]; 80 read_memory (SCM2PTR (svalue) + index * TYPE_LENGTH (builtin_type_scm), 81 buffer, TYPE_LENGTH (builtin_type_scm)); 82 return extract_signed_integer (buffer, TYPE_LENGTH (builtin_type_scm)); 83 } 84 85 /* Unpack a value of type TYPE in buffer VALADDR as an integer 86 (if CONTEXT == TYPE_CODE_IN), a pointer (CONTEXT == TYPE_CODE_PTR), 87 or Boolean (CONTEXT == TYPE_CODE_BOOL). */ 88 89 LONGEST 90 scm_unpack (struct type *type, const char *valaddr, enum type_code context) 91 { 92 if (is_scmvalue_type (type)) 93 { 94 LONGEST svalue = extract_signed_integer (valaddr, TYPE_LENGTH (type)); 95 if (context == TYPE_CODE_BOOL) 96 { 97 if (svalue == SCM_BOOL_F) 98 return 0; 99 else 100 return 1; 101 } 102 switch (7 & (int) svalue) 103 { 104 case 2: 105 case 6: /* fixnum */ 106 return svalue >> 2; 107 case 4: /* other immediate value */ 108 if (SCM_ICHRP (svalue)) /* character */ 109 return SCM_ICHR (svalue); 110 else if (SCM_IFLAGP (svalue)) 111 { 112 switch ((int) svalue) 113 { 114 #ifndef SICP 115 case SCM_EOL: 116 #endif 117 case SCM_BOOL_F: 118 return 0; 119 case SCM_BOOL_T: 120 return 1; 121 } 122 } 123 error ("Value can't be converted to integer."); 124 default: 125 return svalue; 126 } 127 } 128 else 129 return unpack_long (type, valaddr); 130 } 131 132 /* True if we're correctly in Guile's eval.c (the evaluator and apply). */ 133 134 static int 135 in_eval_c (void) 136 { 137 struct symtab_and_line cursal = get_current_source_symtab_and_line (); 138 139 if (cursal.symtab && cursal.symtab->filename) 140 { 141 char *filename = cursal.symtab->filename; 142 int len = strlen (filename); 143 if (len >= 6 && strcmp (filename + len - 6, "eval.c") == 0) 144 return 1; 145 } 146 return 0; 147 } 148 149 /* Lookup a value for the variable named STR. 150 First lookup in Scheme context (using the scm_lookup_cstr inferior 151 function), then try lookup_symbol for compiled variables. */ 152 153 static struct value * 154 scm_lookup_name (char *str) 155 { 156 struct value *args[3]; 157 int len = strlen (str); 158 struct value *func; 159 struct value *val; 160 struct symbol *sym; 161 args[0] = value_allocate_space_in_inferior (len); 162 args[1] = value_from_longest (builtin_type_int, len); 163 write_memory (value_as_long (args[0]), str, len); 164 165 if (in_eval_c () 166 && (sym = lookup_symbol ("env", 167 expression_context_block, 168 VAR_DOMAIN, (int *) NULL, 169 (struct symtab **) NULL)) != NULL) 170 args[2] = value_of_variable (sym, expression_context_block); 171 else 172 /* FIXME in this case, we should try lookup_symbol first */ 173 args[2] = value_from_longest (builtin_type_scm, SCM_EOL); 174 175 func = find_function_in_inferior ("scm_lookup_cstr"); 176 val = call_function_by_hand (func, 3, args); 177 if (!value_logical_not (val)) 178 return value_ind (val); 179 180 sym = lookup_symbol (str, 181 expression_context_block, 182 VAR_DOMAIN, (int *) NULL, 183 (struct symtab **) NULL); 184 if (sym) 185 return value_of_variable (sym, NULL); 186 error ("No symbol \"%s\" in current context.", str); 187 } 188 189 struct value * 190 scm_evaluate_string (char *str, int len) 191 { 192 struct value *func; 193 struct value *addr = value_allocate_space_in_inferior (len + 1); 194 LONGEST iaddr = value_as_long (addr); 195 write_memory (iaddr, str, len); 196 /* FIXME - should find and pass env */ 197 write_memory (iaddr + len, "", 1); 198 func = find_function_in_inferior ("scm_evstr"); 199 return call_function_by_hand (func, 1, &addr); 200 } 201 202 static struct value * 203 evaluate_subexp_scm (struct type *expect_type, struct expression *exp, 204 int *pos, enum noside noside) 205 { 206 enum exp_opcode op = exp->elts[*pos].opcode; 207 int len, pc; 208 char *str; 209 switch (op) 210 { 211 case OP_NAME: 212 pc = (*pos)++; 213 len = longest_to_int (exp->elts[pc + 1].longconst); 214 (*pos) += 3 + BYTES_TO_EXP_ELEM (len + 1); 215 if (noside == EVAL_SKIP) 216 goto nosideret; 217 str = &exp->elts[pc + 2].string; 218 return scm_lookup_name (str); 219 case OP_EXPRSTRING: 220 pc = (*pos)++; 221 len = longest_to_int (exp->elts[pc + 1].longconst); 222 (*pos) += 3 + BYTES_TO_EXP_ELEM (len + 1); 223 if (noside == EVAL_SKIP) 224 goto nosideret; 225 str = &exp->elts[pc + 2].string; 226 return scm_evaluate_string (str, len); 227 default:; 228 } 229 return evaluate_subexp_standard (expect_type, exp, pos, noside); 230 nosideret: 231 return value_from_longest (builtin_type_long, (LONGEST) 1); 232 } 233 234 const struct exp_descriptor exp_descriptor_scm = 235 { 236 print_subexp_standard, 237 operator_length_standard, 238 op_name_standard, 239 dump_subexp_body_standard, 240 evaluate_subexp_scm 241 }; 242 243 const struct language_defn scm_language_defn = 244 { 245 "scheme", /* Language name */ 246 language_scm, 247 NULL, 248 range_check_off, 249 type_check_off, 250 case_sensitive_off, 251 array_row_major, 252 &exp_descriptor_scm, 253 scm_parse, 254 c_error, 255 null_post_parser, 256 scm_printchar, /* Print a character constant */ 257 scm_printstr, /* Function to print string constant */ 258 NULL, /* Function to print a single character */ 259 NULL, /* Create fundamental type in this language */ 260 c_print_type, /* Print a type using appropriate syntax */ 261 scm_val_print, /* Print a value using appropriate syntax */ 262 scm_value_print, /* Print a top-level value */ 263 NULL, /* Language specific skip_trampoline */ 264 value_of_this, /* value_of_this */ 265 basic_lookup_symbol_nonlocal, /* lookup_symbol_nonlocal */ 266 basic_lookup_transparent_type,/* lookup_transparent_type */ 267 NULL, /* Language specific symbol demangler */ 268 NULL, /* Language specific class_name_from_physname */ 269 NULL, /* expression operators for printing */ 270 1, /* c-style arrays */ 271 0, /* String lower bound */ 272 NULL, 273 default_word_break_characters, 274 c_language_arch_info, 275 LANG_MAGIC 276 }; 277 278 void 279 _initialize_scheme_language (void) 280 { 281 add_language (&scm_language_defn); 282 builtin_type_scm = init_type (TYPE_CODE_INT, 283 TARGET_LONG_BIT / TARGET_CHAR_BIT, 284 0, "SCM", (struct objfile *) NULL); 285 } 286