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->declaration->type;
  48
  49                 field_type->copy(dest, fdest, src, fsrc, field->declaration);
  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         free_type_scope(struct_type->scope);
  64         g_hash_table_destroy(struct_type->fields_by_name);
  65
  66         for (i = 0; i < struct_type->fields->len; i++) {
  67                 struct type_field *type_field =
  68                         &g_array_index(struct_type->fields,
  69                                        struct type_field, i);
  70                 type_unref(type_field->type);
  71         }
  72         g_array_free(struct_type->fields, true);
  73         g_free(struct_type);
  74 }
  75
  76 struct type_struct *struct_type_new(const char *name,
  77                                     struct type_scope *parent_scope)
  78 {
  79         struct type_struct *struct_type;
  80         struct type *type;
  81
  82         struct_type = g_new(struct type_struct, 1);
  83         type = &struct_type->p;
  84         struct_type->fields_by_name = g_hash_table_new(g_direct_hash,
  85                                                        g_direct_equal);
  86         struct_type->fields = g_array_sized_new(FALSE, TRUE,
  87                                                 sizeof(struct type_field),
  88                                                 DEFAULT_NR_STRUCT_FIELDS);
  89         struct_type->scope = new_type_scope(parent_scope);
  90         type->name = g_quark_from_string(name);
  91         type->alignment = 1;
  92         type->copy = struct_copy;
  93         type->type_free = _struct_type_free;
  94         type->declaration_new = _struct_declaration_new;
  95         type->declaration_free = _struct_declaration_free;
  96         type->ref = 1;
  97         return struct_type;
  98 }
  99
 100 static
 101 struct declaration *
 102         _struct_declaration_new(struct type *type,
 103                                 struct declaration_scope *parent_scope)
 104 {
 105         struct type_struct *struct_type =
 106                 container_of(type, struct type_struct, p);
 107         struct declaration_struct *_struct;
 108         unsigned long i;
 109         int ret;
 110
 111         _struct = g_new(struct declaration_struct, 1);
 112         type_ref(&struct_type->p);
 113         _struct->p.type = type;
 114         _struct->type = struct_type;
 115         _struct->p.ref = 1;
 116         _struct->scope = new_declaration_scope(parent_scope);
 117         _struct->fields = g_array_sized_new(FALSE, TRUE,
 118                                             sizeof(struct field),
 119                                             DEFAULT_NR_STRUCT_FIELDS);
 120         g_array_set_size(_struct->fields, struct_type->fields->len);
 121         for (i = 0; i < struct_type->fields->len; i++) {
 122                 struct type_field *type_field =
 123                         &g_array_index(struct_type->fields,
 124                                        struct type_field, i);
 125                 struct field *field = &g_array_index(_struct->fields,
 126                                                      struct field, i);
 127
 128                 field->name = type_field->name;
 129                 field->declaration =
 130                         type_field->type->declaration_new(type_field->type,
 131                                                           _struct->scope);
 132                 ret = register_declaration(field->name,
 133                                            field->declaration, _struct->scope);
 134                 assert(!ret);
 135         }
 136         return &_struct->p;
 137 }
 138
 139 static
 140 void _struct_declaration_free(struct declaration *declaration)
 141 {
 142         struct declaration_struct *_struct =
 143                 container_of(declaration, struct declaration_struct, p);
 144         unsigned long i;
 145
 146         assert(_struct->fields->len == _struct->type->fields->len);
 147         for (i = 0; i < _struct->fields->len; i++) {
 148                 struct field *field = &g_array_index(_struct->fields,
 149                                                      struct field, i);
 150                 declaration_unref(field->declaration);
 151         }
 152         free_declaration_scope(_struct->scope);
 153         type_unref(_struct->p.type);
 154         g_free(_struct);
 155 }
 156
 157 void struct_type_add_field(struct type_struct *struct_type,
 158                            const char *field_name,
 159                            struct type *field_type)
 160 {
 161         struct type_field *field;
 162         unsigned long index;
 163
 164         g_array_set_size(struct_type->fields, struct_type->fields->len + 1);
 165         index = struct_type->fields->len - 1;   /* last field (new) */
 166         field = &g_array_index(struct_type->fields, struct type_field, index);
 167         field->name = g_quark_from_string(field_name);
 168         type_ref(field_type);
 169         field->type = field_type;
 170         /* Keep index in hash rather than pointer, because array can relocate */
 171         g_hash_table_insert(struct_type->fields_by_name,
 172                             (gpointer) (unsigned long) field->name,
 173                             (gpointer) index);
 174         /*
 175          * Alignment of structure is the max alignment of types contained
 176          * therein.
 177          */
 178         struct_type->p.alignment = max(struct_type->p.alignment,
 179                                        field_type->alignment);
 180 }
 181
 182 unsigned long
 183         struct_type_lookup_field_index(struct type_struct *struct_type,
 184                                        GQuark field_name)
 185 {
 186         unsigned long index;
 187
 188         index = (unsigned long) g_hash_table_lookup(struct_type->fields_by_name,
 189                                                     (gconstpointer) (unsigned long) field_name);
 190         return index;
 191 }
 192
 193 /*
 194  * field returned only valid as long as the field structure is not appended to.
 195  */
 196 struct type_field *
 197         struct_type_get_field_from_index(struct type_struct *struct_type,
 198                                          unsigned long index)
 199 {
 200         return &g_array_index(struct_type->fields, struct type_field, index);
 201 }
 202
 203 /*
 204  * field returned only valid as long as the field structure is not appended to.
 205  */
 206 struct field *
 207 struct_declaration_get_field_from_index(struct declaration_struct *_struct,
 208                                         unsigned long index)
 209 {
 210         return &g_array_index(_struct->fields, struct field, index);
 211 }