types/sequence.c

   1 /*
   2  * sequence.c
   3  *
   4  * BabelTrace - Sequence 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 #include <inttypes.h>
  22
  23 static
  24 struct definition *_sequence_definition_new(struct declaration *declaration,
  25                                         struct definition_scope *parent_scope,
  26                                         GQuark field_name, int index,
  27                                         const char *root_name);
  28 static
  29 void _sequence_definition_free(struct definition *definition);
  30
  31 int sequence_rw(struct stream_pos *pos, struct definition *definition)
  32 {
  33         struct definition_sequence *sequence_definition =
  34                 container_of(definition, struct definition_sequence, p);
  35         const struct declaration_sequence *sequence_declaration =
  36                 sequence_definition->declaration;
  37         uint64_t len, oldlen, i;
  38         int ret;
  39
  40         len = sequence_definition->length->value._unsigned;
  41         /*
  42          * Yes, large sequences could be _painfully slow_ to parse due
  43          * to memory allocation for each event read. At least, never
  44          * shrink the sequence. Note: the sequence GArray len should
  45          * never be used as indicator of the current sequence length.
  46          * One should always look at the sequence->len->value._unsigned
  47          * value for that.
  48          */
  49         oldlen = sequence_definition->elems->len;
  50         if (oldlen < len)
  51                 g_ptr_array_set_size(sequence_definition->elems, len);
  52
  53         for (i = oldlen; i < len; i++) {
  54                 struct definition **field;
  55                 GString *str;
  56                 GQuark name;
  57
  58                 str = g_string_new("");
  59                 g_string_printf(str, "[%" PRIu64 "]", i);
  60                 (void) g_string_free(str, TRUE);
  61                 name = g_quark_from_string(str->str);
  62
  63                 field = (struct definition **) &g_ptr_array_index(sequence_definition->elems, i);
  64                 *field = sequence_declaration->elem->definition_new(sequence_declaration->elem,
  65                                           sequence_definition->scope,
  66                                           name, i, NULL);
  67                 ret = generic_rw(pos, *field);
  68                 if (ret)
  69                         return ret;
  70         }
  71         return 0;
  72 }
  73
  74 static
  75 void _sequence_declaration_free(struct declaration *declaration)
  76 {
  77         struct declaration_sequence *sequence_declaration =
  78                 container_of(declaration, struct declaration_sequence, p);
  79
  80         free_declaration_scope(sequence_declaration->scope);
  81         g_array_free(sequence_declaration->length_name, TRUE);
  82         declaration_unref(sequence_declaration->elem);
  83         g_free(sequence_declaration);
  84 }
  85
  86 struct declaration_sequence *
  87         sequence_declaration_new(const char *length,
  88                           struct declaration *elem_declaration,
  89                           struct declaration_scope *parent_scope)
  90 {
  91         struct declaration_sequence *sequence_declaration;
  92         struct declaration *declaration;
  93
  94         sequence_declaration = g_new(struct declaration_sequence, 1);
  95         declaration = &sequence_declaration->p;
  96
  97         sequence_declaration->length_name = g_array_new(FALSE, TRUE, sizeof(GQuark));
  98         append_scope_path(length, sequence_declaration->length_name);
  99
 100         declaration_ref(elem_declaration);
 101         sequence_declaration->elem = elem_declaration;
 102         sequence_declaration->scope = new_declaration_scope(parent_scope);
 103         declaration->id = CTF_TYPE_SEQUENCE;
 104         declaration->alignment = elem_declaration->alignment;
 105         declaration->declaration_free = _sequence_declaration_free;
 106         declaration->definition_new = _sequence_definition_new;
 107         declaration->definition_free = _sequence_definition_free;
 108         declaration->ref = 1;
 109         return sequence_declaration;
 110 }
 111
 112 static
 113 struct definition *_sequence_definition_new(struct declaration *declaration,
 114                                 struct definition_scope *parent_scope,
 115                                 GQuark field_name, int index,
 116                                 const char *root_name)
 117 {
 118         struct declaration_sequence *sequence_declaration =
 119                 container_of(declaration, struct declaration_sequence, p);
 120         struct definition_sequence *sequence;
 121         struct definition *len_parent;
 122         int ret;
 123
 124         sequence = g_new(struct definition_sequence, 1);
 125         declaration_ref(&sequence_declaration->p);
 126         sequence->p.declaration = declaration;
 127         sequence->declaration = sequence_declaration;
 128         sequence->p.ref = 1;
 129         /*
 130          * Use INT_MAX order to ensure that all fields of the parent
 131          * scope are seen as being prior to this scope.
 132          */
 133         sequence->p.index = root_name ? INT_MAX : index;
 134         sequence->p.name = field_name;
 135         sequence->p.path = new_definition_path(parent_scope, field_name, root_name);
 136         sequence->scope = new_definition_scope(parent_scope, field_name, root_name);
 137         ret = register_field_definition(field_name, &sequence->p,
 138                                         parent_scope);
 139         assert(!ret);
 140         len_parent = lookup_definition(sequence->scope->scope_path,
 141                                        sequence_declaration->length_name,
 142                                        parent_scope);
 143         if (!len_parent) {
 144                 printf("[error] Lookup for sequence length field failed.\n");
 145                 goto error;
 146         }
 147         sequence->length =
 148                 container_of(len_parent, struct definition_integer, p);
 149         if (sequence->length->declaration->signedness) {
 150                 printf("[error] Sequence length field should be unsigned.\n");
 151                 goto error;
 152         }
 153         definition_ref(len_parent);
 154         sequence->elems = g_ptr_array_new();
 155         return &sequence->p;
 156
 157 error:
 158         free_definition_scope(sequence->scope);
 159         declaration_unref(&sequence_declaration->p);
 160         g_free(sequence);
 161         return NULL;
 162 }
 163
 164 static
 165 void _sequence_definition_free(struct definition *definition)
 166 {
 167         struct definition_sequence *sequence =
 168                 container_of(definition, struct definition_sequence, p);
 169         struct definition *len_definition = &sequence->length->p;
 170         uint64_t i;
 171
 172         for (i = 0; i < sequence->elems->len; i++) {
 173                 struct definition *field;
 174
 175                 field = g_ptr_array_index(sequence->elems, i);
 176                 field->declaration->definition_free(field);
 177         }
 178         (void) g_ptr_array_free(sequence->elems, TRUE);
 179         definition_unref(len_definition);
 180         free_definition_scope(sequence->scope);
 181         declaration_unref(sequence->p.declaration);
 182         g_free(sequence);
 183 }
 184
 185 uint64_t sequence_len(struct definition_sequence *sequence)
 186 {
 187         return sequence->length->value._unsigned;
 188 }
 189
 190 struct definition *sequence_index(struct definition_sequence *sequence, uint64_t i)
 191 {
 192         if (i >= sequence->length->value._unsigned)
 193                 return NULL;
 194         assert(i < sequence->elems->len);
 195         return g_ptr_array_index(sequence->elems, i);
 196 }