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