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 declaration *_struct_declaration_new(struct type *type,
  28                                 struct declaration_scope *parent_scope);
  29 static
  30 void _struct_declaration_free(struct declaration *declaration);
  31
  32 void struct_copy(struct stream_pos *dest, const struct format *fdest,
  33                  struct stream_pos *src, const struct format *fsrc,
  34                  struct declaration *declaration)
  35 {
  36         struct declaration_struct *_struct =
  37                 container_of(declaration, struct declaration_struct, p);
  38         struct type_struct *struct_type = _struct->type;
  39         unsigned long i;
  40
  41         fsrc->struct_begin(src, struct_type);
  42         fdest->struct_begin(dest, struct_type);
  43
  44         for (i = 0; i < _struct->fields->len; i++) {
  45                 struct field *field = &g_array_index(_struct->fields,
  46                                                      struct field, i);
  47                 struct type *field_type = field->type->p.type;
  48
  49                 field_type->copy(dest, fdest, src, fsrc, &field->type->p);
  50
  51         }
  52         fsrc->struct_end(src, struct_type);
  53         fdest->struct_end(dest, struct_type);
  54 }
  55
  56 static
  57 void _struct_type_free(struct type *type)
  58 {
  59         struct type_struct *struct_type =
  60                 container_of(type, struct type_struct, p);
  61         unsigned long i;
  62
  63         g_hash_table_destroy(struct_type->fields_by_name);
  64
  65         for (i = 0; i < struct_type->fields->len; i++) {
  66                 struct field *type_field =
  67                         &g_array_index(struct_type->fields,
  68                                        struct type_field, i);
  69                 type_unref(field->type);
  70         }
  71         g_array_free(struct_type->fields, true);
  72         g_free(struct_type);
  73 }
  74
  75 struct type_struct *struct_type_new(const char *name)
  76 {
  77         struct type_struct *struct_type;
  78         struct type *type;
  79         int ret;
  80
  81         struct_type = g_new(struct type_struct, 1);
  82         type = &struct_type->p;
  83         struct_type->fields_by_name = g_hash_table_new(g_direct_hash,
  84                                                        g_direct_equal);
  85         struct_type->fields = g_array_sized_new(FALSE, TRUE,
  86                                                 sizeof(struct type_field),
  87                                                 DEFAULT_NR_STRUCT_FIELDS);
  88         type->name = g_quark_from_string(name);
  89         type->alignment = 1;
  90         type->copy = struct_copy;
  91         type->type_free = _struct_type_free;
  92         type->declaration_new = _struct_declaration_new;
  93         type->declaration_free = _struct_declaration_free;
  94         type->ref = 1;
  95
  96         if (type->name) {
  97                 ret = register_type(type);
  98                 if (ret)
  99                         goto error_register;
 100         }
 101         return struct_type;
 102
 103 error_register:
 104         g_hash_table_destroy(struct_type->fields_by_name);
 105         g_array_free(struct_type->fields, true);
 106         g_free(struct_type);
 107         return NULL;
 108 }
 109
 110 static
 111 struct declaration *
 112         _struct_declaration_new(struct type *type,
 113                                 struct declaration_scope *parent_scope)
 114 {
 115         struct type_struct *struct_type =
 116                 container_of(type, struct type_struct, p);
 117         struct declaration_struct *_struct;
 118
 119         _struct = g_new(struct declaration_struct, 1);
 120         type_ref(&struct_type->p);
 121         _struct->p.type = struct_type;
 122         _struct->p.ref = 1;
 123         _struct->scope = new_declaration_scope(parent_scope);
 124         _struct->fields = g_array_sized_new(FALSE, TRUE,
 125                                             sizeof(struct field),
 126                                             DEFAULT_NR_STRUCT_FIELDS);
 127         return &_struct->p;
 128 }
 129
 130 static
 131 void _struct_declaration_free(struct declaration *declaration)
 132 {
 133         struct declaration_struct *_struct =
 134                 container_of(declaration, struct declaration_struct, p);
 135         unsigned long i;
 136
 137         for (i = 0; i < _struct->fields->len; i++) {
 138                 struct field *field = &g_array_index(_struct->fields,
 139                                                      struct field, i);
 140                 declaration_unref(field->declaration);
 141         }
 142         free_declaration_scope(_struct->scope);
 143         type_unref(_struct->p.type);
 144         g_free(_struct);
 145 }
 146
 147 void struct_type_add_field(struct type_struct *struct_type,
 148                            const char *field_name,
 149                            struct type *field_type)
 150 {
 151         struct type_field *field;
 152         unsigned long index;
 153
 154         g_array_set_size(struct_type->fields, struct_type->fields->len + 1);
 155         index = struct_type->fields->len - 1;   /* last field (new) */
 156         field = &g_array_index(struct_type->fields, struct type_field, index);
 157         field->name = g_quark_from_string(field_name);
 158         type_ref(field_type);
 159         field->type = field_type;
 160         /* Keep index in hash rather than pointer, because array can relocate */
 161         g_hash_table_insert(struct_type->fields_by_name,
 162                             (gpointer) (unsigned long) field->name,
 163                             (gpointer) index);
 164         /*
 165          * Alignment of structure is the max alignment of types contained
 166          * therein.
 167          */
 168         struct_type->p.alignment = max(struct_type->p.alignment,
 169                                        field_type->alignment);
 170 }
 171
 172 unsigned long
 173         struct_type_lookup_field_index(struct type_struct *struct_type,
 174                                        GQuark field_name)
 175 {
 176         unsigned long index;
 177
 178         index = (unsigned long) g_hash_table_lookup(struct_type->fields_by_name,
 179                                                     (gconstpointer) (unsigned long) field_name);
 180         return index;
 181 }
 182
 183 /*
 184  * field returned only valid as long as the field structure is not appended to.
 185  */
 186 struct type_field *
 187         struct_type_get_field_from_index(struct type_struct *struct_type,
 188                                          unsigned long index)
 189 {
 190         return &g_array_index(struct_type->fields, struct type_field, index);
 191 }
 192
 193 /*
 194  * field returned only valid as long as the field structure is not appended to.
 195  */
 196 struct field *
 197 struct_declaration_get_field_from_index(struct declaration_struct *_struct,
 198                                         unsigned long index)
 199 {
 200         return &g_array_index(_struct->fields, struct field, index);
 201 }