types/struct.c

   1 /*
   2  * struct.c
   3  *
   4  * BabelTrace - Structure Type Converter
   5  *
   6  * Copyright 2010, 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  */
  18
  19 #include <babeltrace/compiler.h>
  20 #include <babeltrace/format.h>
  21
  22 #ifndef max
  23 #define max(a, b)       ((a) < (b) ? (b) : (a))
  24 #endif
  25
  26 static
  27 struct type *_struct_type_new(struct type_class *type_class,
  28                              struct declaration_scope *parent_scope);
  29 static
  30 void _struct_type_free(struct type *type);
  31
  32 void struct_copy(struct stream_pos *dest, const struct format *fdest,
  33                  struct stream_pos *src, const struct format *fsrc,
  34                  struct type *type)
  35 {
  36         struct type_struct *_struct = container_of(type, struct type_struct, p);
  37         struct type_class_struct *struct_class = _struct->_class;
  38         unsigned long i;
  39
  40         fsrc->struct_begin(src, struct_class);
  41         fdest->struct_begin(dest, struct_class);
  42
  43         for (i = 0; i < _struct->fields->len; i++) {
  44                 struct field *field = &g_array_index(_struct->fields,
  45                                                      struct field, i);
  46                 struct type_class *field_class = field->type->p._class;
  47
  48                 field_class->copy(dest, fdest, src, fsrc, &field->type->p);
  49
  50         }
  51         fsrc->struct_end(src, struct_class);
  52         fdest->struct_end(dest, struct_class);
  53 }
  54
  55 static
  56 void _struct_type_class_free(struct type_class *type_class)
  57 {
  58         struct type_class_struct *struct_class =
  59                 container_of(type_class, struct type_class_struct, p);
  60         unsigned long i;
  61
  62         g_hash_table_destroy(struct_class->fields_by_name);
  63
  64         for (i = 0; i < struct_class->fields->len; i++) {
  65                 struct field *type_class_field =
  66                         &g_array_index(struct_class->fields,
  67                                        struct type_class_field, i);
  68                 type_class_unref(field->type_class);
  69         }
  70         g_array_free(struct_class->fields, true);
  71         g_free(struct_class);
  72 }
  73
  74 struct type_class_struct *
  75 struct_type_class_new(const char *name)
  76 {
  77         struct type_class_struct *struct_class;
  78         struct type_class *type_class;
  79         int ret;
  80
  81         struct_class = g_new(struct type_class_struct, 1);
  82         type_class = &struct_class->p;
  83         struct_class->fields_by_name = g_hash_table_new(g_direct_hash,
  84                                                         g_direct_equal);
  85         struct_class->fields = g_array_sized_new(FALSE, TRUE,
  86                                                  sizeof(struct type_class_field),
  87                                                  DEFAULT_NR_STRUCT_FIELDS);
  88         type_class->name = g_quark_from_string(name);
  89         type_class->alignment = 1;
  90         type_class->copy = struct_copy;
  91         type_class->class_free = _struct_type_class_free;
  92         type_class->type_new = _struct_type_new;
  93         type_class->type_free = _struct_type_free;
  94         type_class->ref = 1;
  95
  96         if (type_class->name) {
  97                 ret = register_type(type_class);
  98                 if (ret)
  99                         goto error_register;
 100         }
 101         return struct_class;
 102
 103 error_register:
 104         g_hash_table_destroy(struct_class->fields_by_name);
 105         g_array_free(struct_class->fields, true);
 106         g_free(struct_class);
 107         return NULL;
 108 }
 109
 110 static
 111 struct type_struct *_struct_type_new(struct type_class *type_class,
 112                                      struct declaration_scope *parent_scope)
 113 {
 114         struct type_class_struct *_struct_class =
 115                 container_of(type_class, struct type_class_struct, p);
 116         struct type_struct *_struct;
 117
 118         _struct = g_new(struct type_struct, 1);
 119         type_class_ref(&_struct_class->p);
 120         _struct->p._class = _struct_class;
 121         _struct->p.ref = 1;
 122         _struct->scope = new_declaration_scope(parent_scope);
 123         _struct->fields = g_array_sized_new(FALSE, TRUE,
 124                                             sizeof(struct field),
 125                                             DEFAULT_NR_STRUCT_FIELDS);
 126         return &_struct->p;
 127 }
 128
 129 static
 130 void _struct_type_free(struct type *type)
 131 {
 132         struct type_struct *_struct = container_of(type, struct type_struct, p);
 133         unsigned long i;
 134
 135         for (i = 0; i < _struct->fields->len; i++) {
 136                 struct field *field = &g_array_index(_struct->fields,
 137                                                      struct field, i);
 138                 type_unref(field->type);
 139         }
 140         free_declaration_scope(_struct->scope);
 141         type_class_unref(_struct->p._class);
 142         g_free(_struct);
 143 }
 144
 145 void struct_type_class_add_field(struct type_class_struct *struct_class,
 146                                  const char *field_name,
 147                                  struct type_class *type_class)
 148 {
 149         struct type_class_field *field;
 150         unsigned long index;
 151
 152         g_array_set_size(struct_class->fields, struct_class->fields->len + 1);
 153         index = struct_class->fields->len - 1;  /* last field (new) */
 154         field = &g_array_index(struct_class->fields, struct type_class_field, index);
 155         field->name = g_quark_from_string(field_name);
 156         type_ref(type_class);
 157         field->type_class = type_class;
 158         /* Keep index in hash rather than pointer, because array can relocate */
 159         g_hash_table_insert(struct_class->fields_by_name,
 160                             (gpointer) (unsigned long) field->name,
 161                             (gpointer) index);
 162         /*
 163          * Alignment of structure is the max alignment of types contained
 164          * therein.
 165          */
 166         struct_class->p.alignment = max(struct_class->p.alignment,
 167                                         type_class->alignment);
 168 }
 169
 170 unsigned long
 171 struct_type_class_lookup_field_index(struct type_class_struct *struct_class,
 172                                      GQuark field_name)
 173 {
 174         unsigned long index;
 175
 176         index = (unsigned long) g_hash_table_lookup(struct_class->fields_by_name,
 177                                                     (gconstpointer) (unsigned long) field_name);
 178         return index;
 179 }
 180
 181 /*
 182  * field returned only valid as long as the field structure is not appended to.
 183  */
 184 struct type_class_field *
 185 struct_type_class_get_field_from_index(struct type_class_struct *struct_class,
 186                                        unsigned long index)
 187 {
 188         return &g_array_index(struct_class->fields, struct type_class_field, index);
 189 }
 190
 191 /*
 192  * field returned only valid as long as the field structure is not appended to.
 193  */
 194 struct field *
 195 struct_type_get_field_from_index(struct type_struct *struct_type,
 196                                  unsigned long index)
 197 {
 198         return &g_array_index(struct_type->fields, struct field, index);
 199 }