1 /* Scheme/Guile language support routines for GDB, the GNU debugger. 2 Copyright 1995 Free Software Foundation, Inc. 3 4 This file is part of GDB. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software 18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 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 "value.h" 27 #include "c-lang.h" 28 #include "scm-lang.h" 29 #include "scm-tags.h" 30 #include "gdb_string.h" 31 #include "gdbcore.h" 32 33 static value_ptr evaluate_subexp_scm PARAMS ((struct type *, struct expression *, 34 int *, enum noside)); 35 static value_ptr scm_lookup_name PARAMS ((char *)); 36 static int in_eval_c PARAMS ((void)); 37 static void scm_printstr PARAMS ((GDB_FILE *, char *, unsigned int, int)); 38 39 extern struct type ** CONST_PTR (c_builtin_types[]); 40 41 struct type *builtin_type_scm; 42 43 void 44 scm_printchar (c, stream) 45 int c; 46 GDB_FILE *stream; 47 { 48 fprintf_filtered (stream, "#\\%c", c); 49 } 50 51 static void 52 scm_printstr (stream, string, length, force_ellipses) 53 GDB_FILE *stream; 54 char *string; 55 unsigned int length; 56 int force_ellipses; 57 { 58 fprintf_filtered (stream, "\"%s\"", string); 59 } 60 61 int 62 is_scmvalue_type (type) 63 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 (svalue, index) 78 LONGEST svalue; 79 int index; 80 { 81 char buffer[20]; 82 read_memory (SCM2PTR (svalue) + index * TYPE_LENGTH (builtin_type_scm), 83 buffer, TYPE_LENGTH (builtin_type_scm)); 84 return extract_signed_integer (buffer, TYPE_LENGTH (builtin_type_scm)); 85 } 86 87 /* Unpack a value of type TYPE in buffer VALADDR as an integer 88 (if CONTEXT == TYPE_CODE_IN), a pointer (CONTEXT == TYPE_CODE_PTR), 89 or Boolean (CONTEXT == TYPE_CODE_BOOL). */ 90 91 LONGEST 92 scm_unpack (type, valaddr, context) 93 struct type *type; 94 char *valaddr; 95 enum type_code context; 96 { 97 if (is_scmvalue_type (type)) 98 { 99 LONGEST svalue = extract_signed_integer (valaddr, TYPE_LENGTH (type)); 100 if (context == TYPE_CODE_BOOL) 101 { 102 if (svalue == SCM_BOOL_F) 103 return 0; 104 else 105 return 1; 106 } 107 switch (7 & svalue) 108 { 109 case 2: case 6: /* fixnum */ 110 return svalue >> 2; 111 case 4: /* other immediate value */ 112 if (SCM_ICHRP (svalue)) /* character */ 113 return SCM_ICHR (svalue); 114 else if (SCM_IFLAGP (svalue)) 115 { 116 switch (svalue) 117 { 118 #ifndef SICP 119 case SCM_EOL: 120 #endif 121 case SCM_BOOL_F: 122 return 0; 123 case SCM_BOOL_T: 124 return 1; 125 } 126 } 127 error ("Value can't be converted to integer."); 128 default: 129 return svalue; 130 } 131 } 132 else 133 return unpack_long (type, valaddr); 134 } 135 136 /* True if we're correctly in Guile's eval.c (the evaluator and apply). */ 137 138 static int 139 in_eval_c () 140 { 141 if (current_source_symtab && current_source_symtab->filename) 142 { 143 char *filename = current_source_symtab->filename; 144 int len = strlen (filename); 145 if (len >= 6 && strcmp (filename + len - 6, "eval.c") == 0) 146 return 1; 147 } 148 return 0; 149 } 150 151 /* Lookup a value for the variable named STR. 152 First lookup in Scheme context (using the scm_lookup_cstr inferior 153 function), then try lookup_symbol for compiled variables. */ 154 155 static value_ptr 156 scm_lookup_name (str) 157 char *str; 158 { 159 value_ptr args[3]; 160 int len = strlen (str); 161 value_ptr func, val; 162 struct symbol *sym; 163 args[0] = value_allocate_space_in_inferior (len); 164 args[1] = value_from_longest (builtin_type_int, len); 165 write_memory (value_as_long (args[0]), str, len); 166 167 if (in_eval_c () 168 && (sym = lookup_symbol ("env", 169 expression_context_block, 170 VAR_NAMESPACE, (int *) NULL, 171 (struct symtab **) NULL)) != NULL) 172 args[2] = value_of_variable (sym, expression_context_block); 173 else 174 /* FIXME in this case, we should try lookup_symbol first */ 175 args[2] = value_from_longest (builtin_type_scm, SCM_EOL); 176 177 func = find_function_in_inferior ("scm_lookup_cstr"); 178 val = call_function_by_hand (func, 3, args); 179 if (!value_logical_not (val)) 180 return value_ind (val); 181 182 sym = lookup_symbol (str, 183 expression_context_block, 184 VAR_NAMESPACE, (int *) NULL, 185 (struct symtab **) NULL); 186 if (sym) 187 return value_of_variable (sym, NULL); 188 error ("No symbol \"%s\" in current context."); 189 } 190 191 value_ptr 192 scm_evaluate_string (str, len) 193 char *str; int len; 194 { 195 value_ptr func; 196 value_ptr addr = value_allocate_space_in_inferior (len + 1); 197 LONGEST iaddr = value_as_long (addr); 198 write_memory (iaddr, str, len); 199 /* FIXME - should find and pass env */ 200 write_memory (iaddr + len, "", 1); 201 func = find_function_in_inferior ("scm_evstr"); 202 return call_function_by_hand (func, 1, &addr); 203 } 204 205 static value_ptr 206 evaluate_subexp_scm (expect_type, exp, pos, noside) 207 struct type *expect_type; 208 register struct expression *exp; 209 register int *pos; 210 enum noside noside; 211 { 212 enum exp_opcode op = exp->elts[*pos].opcode; 213 int len, pc; char *str; 214 switch (op) 215 { 216 case OP_NAME: 217 pc = (*pos)++; 218 len = longest_to_int (exp->elts[pc + 1].longconst); 219 (*pos) += 3 + BYTES_TO_EXP_ELEM (len + 1); 220 if (noside == EVAL_SKIP) 221 goto nosideret; 222 str = &exp->elts[pc + 2].string; 223 return scm_lookup_name (str); 224 case OP_EXPRSTRING: 225 pc = (*pos)++; 226 len = longest_to_int (exp->elts[pc + 1].longconst); 227 (*pos) += 3 + BYTES_TO_EXP_ELEM (len + 1); 228 if (noside == EVAL_SKIP) 229 goto nosideret; 230 str = &exp->elts[pc + 2].string; 231 return scm_evaluate_string (str, len); 232 default: ; 233 } 234 return evaluate_subexp_standard (expect_type, exp, pos, noside); 235 nosideret: 236 return value_from_longest (builtin_type_long, (LONGEST) 1); 237 } 238 239 const struct language_defn scm_language_defn = { 240 "scheme", /* Language name */ 241 language_scm, 242 c_builtin_types, 243 range_check_off, 244 type_check_off, 245 scm_parse, 246 c_error, 247 evaluate_subexp_scm, 248 scm_printchar, /* Print a character constant */ 249 scm_printstr, /* Function to print string constant */ 250 NULL, /* Create fundamental type in this language */ 251 c_print_type, /* Print a type using appropriate syntax */ 252 scm_val_print, /* Print a value using appropriate syntax */ 253 scm_value_print, /* Print a top-level value */ 254 {"", "", "", ""}, /* Binary format info */ 255 {"#o%lo", "#o", "o", ""}, /* Octal format info */ 256 {"%ld", "", "d", ""}, /* Decimal format info */ 257 {"#x%lX", "#X", "X", ""}, /* Hex format info */ 258 NULL, /* expression operators for printing */ 259 1, /* c-style arrays */ 260 0, /* String lower bound */ 261 &builtin_type_char, /* Type of string elements */ 262 LANG_MAGIC 263 }; 264 265 void 266 _initialize_scheme_language () 267 { 268 add_language (&scm_language_defn); 269 builtin_type_scm = init_type (TYPE_CODE_INT, 270 TARGET_LONG_BIT / TARGET_CHAR_BIT, 271 0, "SCM", (struct objfile *) NULL); 272 } 273