1 /* Common operations. */ 2 3 #include <stdlib.h> 4 #include "ops.h" 5 #include "progconsts.h" 6 #include "progtypes.h" 7 8 /* Direct access and manipulation of static objects. */ 9 10 __attr __load_static(__ref parent, __ref obj) 11 { 12 __attr out = {.context=parent, .value=obj}; 13 return out; 14 } 15 16 /* Direct retrieval operations, returning and setting attributes. */ 17 18 __attr __load_via_object(__ref obj, int pos) 19 { 20 return obj->attrs[pos]; 21 } 22 23 __attr __load_via_class(__ref obj, int pos) 24 { 25 return __load_via_object(__get_class(obj), pos); 26 } 27 28 __attr __get_class_and_load(__ref obj, int pos) 29 { 30 if (__is_instance(obj)) 31 return __load_via_class(obj, pos); 32 else 33 return __load_via_object(obj, pos); 34 } 35 36 /* Direct storage operations. */ 37 38 int __store_via_object(__ref obj, int pos, __attr value) 39 { 40 obj->attrs[pos] = value; 41 return 1; 42 } 43 44 /* Introspection. */ 45 46 int __is_instance(__ref obj) 47 { 48 return obj->pos == __INSTANCEPOS; 49 } 50 51 __ref __get_class(__ref obj) 52 { 53 return __load_via_object(obj, __pos___class__).value; 54 } 55 56 /* Attribute testing operations. */ 57 58 __ref __test_specific_instance(__ref obj, __ref type) 59 { 60 return __get_class(obj) == type ? obj : 0; 61 } 62 63 __ref __test_common_instance(__ref obj, int pos, int code) 64 { 65 return __HASATTR(__get_class(obj), pos, code) ? obj : 0; 66 } 67 68 __ref __test_common_object(__ref obj, int pos, int code) 69 { 70 return __test_common_type(obj, pos, code) || __test_common_instance(obj, pos, code) ? obj : 0; 71 } 72 73 __ref __test_common_type(__ref obj, int pos, int code) 74 { 75 return __HASATTR(obj, pos, code) ? obj : 0; 76 } 77 78 /* Attribute testing and retrieval operations. */ 79 80 __attr __check_and_load_via_class(__ref obj, int pos, int code) 81 { 82 return __check_and_load_via_object(__get_class(obj), pos, code); 83 } 84 85 __attr __check_and_load_via_object(__ref obj, int pos, int code) 86 { 87 return __HASATTR(obj, pos, code) ? __load_via_object(obj, pos) : __NULL; 88 } 89 90 __attr __check_and_load_via_any(__ref obj, int pos, int code) 91 { 92 __attr out = __check_and_load_via_object(obj, pos, code); 93 if (out.value == 0) 94 out = __check_and_load_via_class(obj, pos, code); 95 return out; 96 } 97 98 /* Attribute testing and storage operations. */ 99 100 int __check_and_store_via_object(__ref obj, int pos, int code, __attr value) 101 { 102 if (__HASATTR(obj, pos, code)) 103 { 104 __store_via_object(obj, pos, value); 105 return 1; 106 } 107 return 0; 108 } 109 110 int __check_and_store_via_any(__ref obj, int pos, int code, __attr value) 111 { 112 if (__check_and_store_via_object(obj, pos, code, value)) 113 return 1; 114 return __check_and_store_via_object(__get_class(obj), pos, code, value); 115 } 116 117 /* Context-related operations. */ 118 119 __attr __test_context(__ref context, __attr attr) 120 { 121 if (__is_instance(attr.context)) 122 return attr; 123 if (__test_common_instance(context, __TYPEPOS(attr.context), __TYPECODE(attr.context))) 124 return __replace_context(context, attr); 125 126 /* NOTE: An error may be more appropriate. */ 127 128 return __NULL; 129 } 130 131 __attr __replace_context(__ref context, __attr attr) 132 { 133 __attr out; 134 135 /* Set the context. */ 136 137 out.context = context; 138 139 /* Reference a callable version of the attribute by obtaining the bound 140 method reference from the __fn__ special attribute. */ 141 142 out.value = __load_via_object(attr.value, __ATTRPOS(__fn__)).b; 143 return out; 144 } 145 146 __attr __update_context(__ref context, __attr attr) 147 { 148 __attr out = {context, .fn=attr.fn}; 149 return out; 150 } 151 152 /* Basic structure tests. */ 153 154 int __WITHIN(__ref obj, int pos) 155 { 156 return pos < obj->table->size; 157 } 158 159 int __HASATTR(__ref obj, int pos, int code) 160 { 161 return __WITHIN(obj, pos) && (obj->table->attrs[pos] == code); 162 } 163 164 /* Parameter position operations. */ 165 166 int __HASPARAM(const __ptable *ptable, int ppos, int pcode) 167 { 168 __param param; 169 170 if (ppos < ptable->size) 171 { 172 param = ptable->params[ppos]; 173 if (param.code == pcode) 174 return param.pos; 175 } 176 177 return -1; 178 } 179 180 /* Conversions. */ 181 182 __attr __CONTEXT_AS_VALUE(__attr attr) 183 { 184 __attr out; 185 out.context = attr.context; 186 out.value = attr.context; 187 return out; 188 } 189 190 /* Type testing. */ 191 192 __ref __ISFUNC(__ref obj) 193 { 194 return __test_specific_instance(obj, &__FUNCTION_TYPE); 195 } 196 197 int __ISNULL(__attr value) 198 { 199 /* (value.context == __NULL.context) is superfluous */ 200 return (value.value == 0); /* __NULL.value */ 201 } 202 203 /* Attribute codes and positions for type objects. */ 204 205 unsigned int __TYPECODE(__ref obj) 206 { 207 return obj->table->attrs[obj->pos]; 208 } 209 210 unsigned int __TYPEPOS(__ref obj) 211 { 212 return obj->pos; 213 } 214 215 /* Copying of structures. */ 216 217 __ref __COPY(__ref obj, int size) 218 { 219 __ref copy = calloc(1, size); 220 memcpy(copy, obj, size); 221 return copy; 222 }