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 #ifndef max
  24 #define max(a, b)       ((a) < (b) ? (b) : (a))
  25 #endif
  26
  27 static
  28 struct definition *_sequence_definition_new(struct declaration *declaration,
  29                                         struct definition_scope *parent_scope,
  30                                         GQuark field_name, int index);
  31 static
  32 void _sequence_definition_free(struct definition *definition);
  33
  34 void sequence_copy(struct stream_pos *dest, const struct format *fdest,
  35                    struct stream_pos *src, const struct format *fsrc,
  36                    struct definition *definition)
  37 {
  38         struct definition_sequence *sequence =
  39                 container_of(definition, struct definition_sequence, p);
  40         struct declaration_sequence *sequence_declaration = sequence->declaration;
  41         uint64_t len, oldlen, i;
  42
  43         fsrc->sequence_begin(src, sequence_declaration);
  44         if (fdest)
  45                 fdest->sequence_begin(dest, sequence_declaration);
  46
  47         sequence->len->p.declaration->copy(dest, fdest, src, fsrc,
  48                                     &sequence->len->p);
  49         len = sequence->len->value._unsigned;
  50         g_array_set_size(sequence->elems, len);
  51         /*
  52          * Yes, large sequences could be _painfully slow_ to parse due
  53          * to memory allocation for each event read. At least, never
  54          * shrink the sequence. Note: the sequence GArray len should
  55          * never be used as indicator of the current sequence length.
  56          * One should always look at the sequence->len->value._unsigned
  57          * value for that.
  58          */
  59         oldlen = sequence->elems->len;
  60         if (oldlen < len)
  61                 g_array_set_size(sequence->elems, len);
  62
  63         for (i = oldlen; i < len; i++) {
  64                 struct field *field;
  65                 GString *str;
  66                 GQuark name;
  67
  68                 str = g_string_new("");
  69                 g_string_printf(str, "[%" PRIu64 "]", i);
  70                 (void) g_string_free(str, TRUE);
  71                 name = g_quark_from_string(str->str);
  72
  73                 field = &g_array_index(sequence->elems, struct field, i);
  74                 field->name = name;
  75                 field->definition = sequence_declaration->elem->definition_new(sequence_declaration->elem,
  76                                           sequence->scope,
  77                                           name, i);
  78                 field->definition->declaration->copy(dest, fdest, src, fsrc, field->definition);
  79         }
  80         fsrc->sequence_end(src, sequence_declaration);
  81         if (fdest)
  82                 fdest->sequence_end(dest, sequence_declaration);
  83 }
  84
  85 static
  86 void _sequence_declaration_free(struct declaration *declaration)
  87 {
  88         struct declaration_sequence *sequence_declaration =
  89                 container_of(declaration, struct declaration_sequence, p);
  90
  91         free_declaration_scope(sequence_declaration->scope);
  92         declaration_unref(&sequence_declaration->len_declaration->p);
  93         declaration_unref(sequence_declaration->elem);
  94         g_free(sequence_declaration);
  95 }
  96
  97 struct declaration_sequence *
  98         sequence_declaration_new(struct declaration_integer *len_declaration,
  99                           struct declaration *elem_declaration,
 100                           struct declaration_scope *parent_scope)
 101 {
 102         struct declaration_sequence *sequence_declaration;
 103         struct declaration *declaration;
 104
 105         sequence_declaration = g_new(struct declaration_sequence, 1);
 106         declaration = &sequence_declaration->p;
 107         assert(!len_declaration->signedness);
 108         declaration_ref(&len_declaration->p);
 109         sequence_declaration->len_declaration = len_declaration;
 110         declaration_ref(elem_declaration);
 111         sequence_declaration->elem = elem_declaration;
 112         sequence_declaration->scope = new_declaration_scope(parent_scope);
 113         declaration->id = CTF_TYPE_SEQUENCE;
 114         declaration->alignment = max(len_declaration->p.alignment, elem_declaration->alignment);
 115         declaration->copy = sequence_copy;
 116         declaration->declaration_free = _sequence_declaration_free;
 117         declaration->definition_new = _sequence_definition_new;
 118         declaration->definition_free = _sequence_definition_free;
 119         declaration->ref = 1;
 120         return sequence_declaration;
 121 }
 122
 123 static
 124 struct definition *_sequence_definition_new(struct declaration *declaration,
 125                                 struct definition_scope *parent_scope,
 126                                 GQuark field_name, int index)
 127 {
 128         struct declaration_sequence *sequence_declaration =
 129                 container_of(declaration, struct declaration_sequence, p);
 130         struct definition_sequence *sequence;
 131         struct definition *len_parent;
 132
 133         sequence = g_new(struct definition_sequence, 1);
 134         declaration_ref(&sequence_declaration->p);
 135         sequence->p.declaration = declaration;
 136         sequence->declaration = sequence_declaration;
 137         sequence->p.ref = 1;
 138         sequence->p.index = index;
 139         sequence->scope = new_definition_scope(parent_scope, field_name);
 140         len_parent = sequence_declaration->len_declaration->p.definition_new(&sequence_declaration->len_declaration->p,
 141                                 sequence->scope,
 142                                 g_quark_from_static_string("length"), 0);
 143         sequence->len =
 144                 container_of(len_parent, struct definition_integer, p);
 145         sequence->elems = g_array_new(FALSE, TRUE, sizeof(struct field));
 146         return &sequence->p;
 147 }
 148
 149 static
 150 void _sequence_definition_free(struct definition *definition)
 151 {
 152         struct definition_sequence *sequence =
 153                 container_of(definition, struct definition_sequence, p);
 154         struct definition *len_definition = &sequence->len->p;
 155         uint64_t i;
 156
 157         for (i = 0; i < sequence->elems->len; i++) {
 158                 struct field *field;
 159
 160                 field = &g_array_index(sequence->elems, struct field, i);
 161                 field->definition->declaration->definition_free(field->definition);
 162         }
 163         (void) g_array_free(sequence->elems, TRUE);
 164         len_definition->declaration->definition_free(len_definition);
 165         free_definition_scope(sequence->scope);
 166         declaration_unref(sequence->p.declaration);
 167         g_free(sequence);
 168 }
 169
 170 uint64_t sequence_len(struct definition_sequence *sequence)
 171 {
 172         return sequence->len->value._unsigned;
 173 }
 174
 175 struct definition *sequence_index(struct definition_sequence *sequence, uint64_t i)
 176 {
 177         if (i >= sequence->len->value._unsigned)
 178                 return NULL;
 179         assert(i < sequence->elems->len);
 180         return g_array_index(sequence->elems, struct field, i).definition;
 181 }