types/sequence.c

   1 /*
   2  * sequence.c
   3  *
   4  * BabelTrace - Sequence Type Converter
   5  *
   6  * Copyright 2010-2011 EfficiOS Inc. and Linux Foundation
   7  *
   8  * Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   9  *
  10  * Permission is hereby granted, free of charge, to any person obtaining a copy
  11  * of this software and associated documentation files (the "Software"), to deal
  12  * in the Software without restriction, including without limitation the rights
  13  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14  * copies of the Software, and to permit persons to whom the Software is
  15  * furnished to do so, subject to the following conditions:
  16  *
  17  * The above copyright notice and this permission notice shall be included in
  18  * all copies or substantial portions of the Software.
  19  */
  20
  21 #include <babeltrace/compiler.h>
  22 #include <babeltrace/format.h>
  23 #include <inttypes.h>
  24
  25 static
  26 struct definition *_sequence_definition_new(struct declaration *declaration,
  27                                         struct definition_scope *parent_scope,
  28                                         GQuark field_name, int index,
  29                                         const char *root_name);
  30 static
  31 void _sequence_definition_free(struct definition *definition);
  32
  33 int sequence_rw(struct stream_pos *pos, struct definition *definition)
  34 {
  35         struct definition_sequence *sequence_definition =
  36                 container_of(definition, struct definition_sequence, p);
  37         const struct declaration_sequence *sequence_declaration =
  38                 sequence_definition->declaration;
  39         uint64_t len, oldlen, i;
  40         int ret;
  41
  42         len = sequence_definition->length->value._unsigned;
  43         /*
  44          * Yes, large sequences could be _painfully slow_ to parse due
  45          * to memory allocation for each event read. At least, never
  46          * shrink the sequence. Note: the sequence GArray len should
  47          * never be used as indicator of the current sequence length.
  48          * One should always look at the sequence->len->value._unsigned
  49          * value for that.
  50          */
  51         oldlen = sequence_definition->elems->len;
  52         if (oldlen < len)
  53                 g_ptr_array_set_size(sequence_definition->elems, len);
  54
  55         for (i = oldlen; i < len; i++) {
  56                 struct definition **field;
  57                 GString *str;
  58                 GQuark name;
  59
  60                 str = g_string_new("");
  61                 g_string_printf(str, "[%" PRIu64 "]", i);
  62                 (void) g_string_free(str, TRUE);
  63                 name = g_quark_from_string(str->str);
  64
  65                 field = (struct definition **) &g_ptr_array_index(sequence_definition->elems, i);
  66                 *field = sequence_declaration->elem->definition_new(sequence_declaration->elem,
  67                                           sequence_definition->p.scope,
  68                                           name, i, NULL);
  69                 ret = generic_rw(pos, *field);
  70                 if (ret)
  71                         return ret;
  72         }
  73         return 0;
  74 }
  75
  76 static
  77 void _sequence_declaration_free(struct declaration *declaration)
  78 {
  79         struct declaration_sequence *sequence_declaration =
  80                 container_of(declaration, struct declaration_sequence, p);
  81
  82         free_declaration_scope(sequence_declaration->scope);
  83         g_array_free(sequence_declaration->length_name, TRUE);
  84         declaration_unref(sequence_declaration->elem);
  85         g_free(sequence_declaration);
  86 }
  87
  88 struct declaration_sequence *
  89         sequence_declaration_new(const char *length,
  90                           struct declaration *elem_declaration,
  91                           struct declaration_scope *parent_scope)
  92 {
  93         struct declaration_sequence *sequence_declaration;
  94         struct declaration *declaration;
  95
  96         sequence_declaration = g_new(struct declaration_sequence, 1);
  97         declaration = &sequence_declaration->p;
  98
  99         sequence_declaration->length_name = g_array_new(FALSE, TRUE, sizeof(GQuark));
 100         append_scope_path(length, sequence_declaration->length_name);
 101
 102         declaration_ref(elem_declaration);
 103         sequence_declaration->elem = elem_declaration;
 104         sequence_declaration->scope = new_declaration_scope(parent_scope);
 105         declaration->id = CTF_TYPE_SEQUENCE;
 106         declaration->alignment = elem_declaration->alignment;
 107         declaration->declaration_free = _sequence_declaration_free;
 108         declaration->definition_new = _sequence_definition_new;
 109         declaration->definition_free = _sequence_definition_free;
 110         declaration->ref = 1;
 111         return sequence_declaration;
 112 }
 113
 114 static
 115 struct definition *_sequence_definition_new(struct declaration *declaration,
 116                                 struct definition_scope *parent_scope,
 117                                 GQuark field_name, int index,
 118                                 const char *root_name)
 119 {
 120         struct declaration_sequence *sequence_declaration =
 121                 container_of(declaration, struct declaration_sequence, p);
 122         struct definition_sequence *sequence;
 123         struct definition *len_parent;
 124         int ret;
 125
 126         sequence = g_new(struct definition_sequence, 1);
 127         declaration_ref(&sequence_declaration->p);
 128         sequence->p.declaration = declaration;
 129         sequence->declaration = sequence_declaration;
 130         sequence->p.ref = 1;
 131         /*
 132          * Use INT_MAX order to ensure that all fields of the parent
 133          * scope are seen as being prior to this scope.
 134          */
 135         sequence->p.index = root_name ? INT_MAX : index;
 136         sequence->p.name = field_name;
 137         sequence->p.path = new_definition_path(parent_scope, field_name, root_name);
 138         sequence->p.scope = new_definition_scope(parent_scope, field_name, root_name);
 139         ret = register_field_definition(field_name, &sequence->p,
 140                                         parent_scope);
 141         assert(!ret);
 142         len_parent = lookup_path_definition(sequence->p.scope->scope_path,
 143                                             sequence_declaration->length_name,
 144                                             parent_scope);
 145         if (!len_parent) {
 146                 printf("[error] Lookup for sequence length field failed.\n");
 147                 goto error;
 148         }
 149         sequence->length =
 150                 container_of(len_parent, struct definition_integer, p);
 151         if (sequence->length->declaration->signedness) {
 152                 printf("[error] Sequence length field should be unsigned.\n");
 153                 goto error;
 154         }
 155         definition_ref(len_parent);
 156
 157         sequence->string = NULL;
 158         sequence->elems = NULL;
 159
 160         if (sequence_declaration->elem->id == CTF_TYPE_INTEGER) {
 161                 struct declaration_integer *integer_declaration =
 162                         container_of(sequence_declaration->elem, struct declaration_integer, p);
 163
 164                 if (integer_declaration->encoding == CTF_STRING_UTF8
 165                       || integer_declaration->encoding == CTF_STRING_ASCII) {
 166
 167                         sequence->string = g_string_new("");
 168
 169                         if (integer_declaration->len == CHAR_BIT
 170                             && integer_declaration->p.alignment == CHAR_BIT) {
 171                                 return &sequence->p;
 172                         }
 173                 }
 174         }
 175
 176         sequence->elems = g_ptr_array_new();
 177         return &sequence->p;
 178
 179 error:
 180         free_definition_scope(sequence->p.scope);
 181         declaration_unref(&sequence_declaration->p);
 182         g_free(sequence);
 183         return NULL;
 184 }
 185
 186 static
 187 void _sequence_definition_free(struct definition *definition)
 188 {
 189         struct definition_sequence *sequence =
 190                 container_of(definition, struct definition_sequence, p);
 191         struct definition *len_definition = &sequence->length->p;
 192         uint64_t i;
 193
 194         if (sequence->string)
 195                 (void) g_string_free(sequence->string, TRUE);
 196         if (sequence->elems) {
 197                 for (i = 0; i < sequence->elems->len; i++) {
 198                         struct definition *field;
 199
 200                         field = g_ptr_array_index(sequence->elems, i);
 201                         field->declaration->definition_free(field);
 202                 }
 203         }
 204         (void) g_ptr_array_free(sequence->elems, TRUE);
 205         definition_unref(len_definition);
 206         free_definition_scope(sequence->p.scope);
 207         declaration_unref(sequence->p.declaration);
 208         g_free(sequence);
 209 }
 210
 211 uint64_t sequence_len(struct definition_sequence *sequence)
 212 {
 213         return sequence->length->value._unsigned;
 214 }
 215
 216 struct definition *sequence_index(struct definition_sequence *sequence, uint64_t i)
 217 {
 218         if (!sequence->elems)
 219                 return NULL;
 220         if (i >= sequence->length->value._unsigned)
 221                 return NULL;
 222         assert(i < sequence->elems->len);
 223         return g_ptr_array_index(sequence->elems, i);
 224 }