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 definition *_struct_definition_new(struct declaration *declaration,
  28                                 struct definition_scope *parent_scope,
  29                                 GQuark field_name, int index);
  30 static
  31 void _struct_definition_free(struct definition *definition);
  32
  33 void struct_copy(struct stream_pos *dest, const struct format *fdest,
  34                  struct stream_pos *src, const struct format *fsrc,
  35                  struct definition *definition)
  36 {
  37         struct definition_struct *_struct =
  38                 container_of(definition, struct definition_struct, p);
  39         struct declaration_struct *struct_declaration = _struct->declaration;
  40         unsigned long i;
  41
  42         fsrc->struct_begin(src, struct_declaration);
  43         if (fdest)
  44                 fdest->struct_begin(dest, struct_declaration);
  45
  46         for (i = 0; i < _struct->fields->len; i++) {
  47                 struct field *field = &g_array_index(_struct->fields,
  48                                                      struct field, i);
  49                 struct declaration *field_declaration = field->definition->declaration;
  50
  51                 field_declaration->copy(dest, fdest, src, fsrc, field->definition);
  52
  53         }
  54         fsrc->struct_end(src, struct_declaration);
  55         if (fdest)
  56                 fdest->struct_end(dest, struct_declaration);
  57 }
  58
  59 static
  60 void _struct_declaration_free(struct declaration *declaration)
  61 {
  62         struct declaration_struct *struct_declaration =
  63                 container_of(declaration, struct declaration_struct, p);
  64         unsigned long i;
  65
  66         free_declaration_scope(struct_declaration->scope);
  67         g_hash_table_destroy(struct_declaration->fields_by_name);
  68
  69         for (i = 0; i < struct_declaration->fields->len; i++) {
  70                 struct declaration_field *declaration_field =
  71                         &g_array_index(struct_declaration->fields,
  72                                        struct declaration_field, i);
  73                 declaration_unref(declaration_field->declaration);
  74         }
  75         g_array_free(struct_declaration->fields, true);
  76         g_free(struct_declaration);
  77 }
  78
  79 struct declaration_struct *
  80         struct_declaration_new(struct declaration_scope *parent_scope)
  81 {
  82         struct declaration_struct *struct_declaration;
  83         struct declaration *declaration;
  84
  85         struct_declaration = g_new(struct declaration_struct, 1);
  86         declaration = &struct_declaration->p;
  87         struct_declaration->fields_by_name = g_hash_table_new(g_direct_hash,
  88                                                        g_direct_equal);
  89         struct_declaration->fields = g_array_sized_new(FALSE, TRUE,
  90                                                 sizeof(struct declaration_field),
  91                                                 DEFAULT_NR_STRUCT_FIELDS);
  92         struct_declaration->scope = new_declaration_scope(parent_scope);
  93         declaration->id = CTF_TYPE_STRUCT;
  94         declaration->alignment = 1;
  95         declaration->copy = struct_copy;
  96         declaration->declaration_free = _struct_declaration_free;
  97         declaration->definition_new = _struct_definition_new;
  98         declaration->definition_free = _struct_definition_free;
  99         declaration->ref = 1;
 100         return struct_declaration;
 101 }
 102
 103 static
 104 struct definition *
 105         _struct_definition_new(struct declaration *declaration,
 106                                struct definition_scope *parent_scope,
 107                                GQuark field_name, int index)
 108 {
 109         struct declaration_struct *struct_declaration =
 110                 container_of(declaration, struct declaration_struct, p);
 111         struct definition_struct *_struct;
 112         unsigned long i;
 113         int ret;
 114
 115         _struct = g_new(struct definition_struct, 1);
 116         declaration_ref(&struct_declaration->p);
 117         _struct->p.declaration = declaration;
 118         _struct->declaration = struct_declaration;
 119         _struct->p.ref = 1;
 120         _struct->p.index = index;
 121         _struct->scope = new_definition_scope(parent_scope, field_name);
 122         _struct->fields = g_array_sized_new(FALSE, TRUE,
 123                                             sizeof(struct field),
 124                                             DEFAULT_NR_STRUCT_FIELDS);
 125         g_array_set_size(_struct->fields, struct_declaration->fields->len);
 126         for (i = 0; i < struct_declaration->fields->len; i++) {
 127                 struct declaration_field *declaration_field =
 128                         &g_array_index(struct_declaration->fields,
 129                                        struct declaration_field, i);
 130                 struct field *field = &g_array_index(_struct->fields,
 131                                                      struct field, i);
 132
 133                 field->name = declaration_field->name;
 134                 field->definition =
 135                         declaration_field->declaration->definition_new(declaration_field->declaration,
 136                                                           _struct->scope,
 137                                                           field->name, i);
 138                 ret = register_field_definition(field->name,
 139                                                 field->definition,
 140                                                 _struct->scope);
 141                 assert(!ret);
 142         }
 143         return &_struct->p;
 144 }
 145
 146 static
 147 void _struct_definition_free(struct definition *definition)
 148 {
 149         struct definition_struct *_struct =
 150                 container_of(definition, struct definition_struct, p);
 151         unsigned long i;
 152
 153         assert(_struct->fields->len == _struct->declaration->fields->len);
 154         for (i = 0; i < _struct->fields->len; i++) {
 155                 struct field *field = &g_array_index(_struct->fields,
 156                                                      struct field, i);
 157                 definition_unref(field->definition);
 158         }
 159         free_definition_scope(_struct->scope);
 160         declaration_unref(_struct->p.declaration);
 161         g_free(_struct);
 162 }
 163
 164 void struct_declaration_add_field(struct declaration_struct *struct_declaration,
 165                            const char *field_name,
 166                            struct declaration *field_declaration)
 167 {
 168         struct declaration_field *field;
 169         unsigned long index;
 170
 171         g_array_set_size(struct_declaration->fields, struct_declaration->fields->len + 1);
 172         index = struct_declaration->fields->len - 1;    /* last field (new) */
 173         field = &g_array_index(struct_declaration->fields, struct declaration_field, index);
 174         field->name = g_quark_from_string(field_name);
 175         declaration_ref(field_declaration);
 176         field->declaration = field_declaration;
 177         /* Keep index in hash rather than pointer, because array can relocate */
 178         g_hash_table_insert(struct_declaration->fields_by_name,
 179                             (gpointer) (unsigned long) field->name,
 180                             (gpointer) index);
 181         /*
 182          * Alignment of structure is the max alignment of declarations contained
 183          * therein.
 184          */
 185         struct_declaration->p.alignment = max(struct_declaration->p.alignment,
 186                                        field_declaration->alignment);
 187 }
 188
 189 /*
 190  * struct_declaration_lookup_field_index - returns field index
 191  *
 192  * Returns the index of a field in a structure, or -1 if it does not
 193  * exist.
 194  */
 195 int struct_declaration_lookup_field_index(struct declaration_struct *struct_declaration,
 196                                        GQuark field_name)
 197 {
 198         gpointer index;
 199         gboolean found;
 200
 201         found = g_hash_table_lookup_extended(struct_declaration->fields_by_name,
 202                                     (gconstpointer) (unsigned long) field_name,
 203                                     NULL, &index);
 204         if (!found)
 205                 return -1;
 206         return (int) (unsigned long) index;
 207 }
 208
 209 /*
 210  * field returned only valid as long as the field structure is not appended to.
 211  */
 212 struct declaration_field *
 213         struct_declaration_get_field_from_index(struct declaration_struct *struct_declaration,
 214                                          int index)
 215 {
 216         if (index < 0)
 217                 return NULL;
 218         return &g_array_index(struct_declaration->fields, struct declaration_field, index);
 219 }
 220
 221 /*
 222  * field returned only valid as long as the field structure is not appended to.
 223  */
 224 struct field *
 225 struct_definition_get_field_from_index(struct definition_struct *_struct,
 226                                         int index)
 227 {
 228         if (index < 0)
 229                 return NULL;
 230         return &g_array_index(_struct->fields, struct field, index);
 231 }