src/lib/trace-ir/attributes.c

   1 /*
   2  * Copyright (c) 2015 EfficiOS Inc. and Linux Foundation
   3  * Copyright (c) 2015 Philippe Proulx <pproulx@efficios.com>
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy
   6  * of this software and associated documentation files (the "Software"), to deal
   7  * in the Software without restriction, including without limitation the rights
   8  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   9  * copies of the Software, and to permit persons to whom the Software is
  10  * furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in
  13  * all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  */
  23
  24 #define BT_LOG_TAG "LIB/ATTRS"
  25 #include "lib/logging.h"
  26
  27 #include "common/macros.h"
  28 #include <babeltrace2/value.h>
  29 #include "lib/assert-pre.h"
  30 #include "lib/object.h"
  31 #include <babeltrace2/value-const.h>
  32 #include "lib/value.h"
  33 #include "attributes.h"
  34 #include <inttypes.h>
  35 #include "compat/string.h"
  36 #include "common/assert.h"
  37
  38 #define BT_ATTR_NAME_INDEX              0
  39 #define BT_ATTR_VALUE_INDEX             1
  40
  41 BT_HIDDEN
  42 struct bt_value *bt_attributes_create(void)
  43 {
  44         struct bt_value *attr_obj;
  45
  46         /*
  47          * Attributes: array value object of array value objects, each one
  48          * containing two entries: a string value object (attributes
  49          * field name), and a value object (attributes field value).
  50          *
  51          * Example (JSON representation):
  52          *
  53          *     [
  54          *         ["hostname", "eeppdesk"],
  55          *         ["sysname", "Linux"],
  56          *         ["tracer_major", 2],
  57          *         ["tracer_minor", 5]
  58          *     ]
  59          */
  60         BT_LOGD_STR("Creating attributes object.");
  61         attr_obj = bt_value_array_create();
  62         if (!attr_obj) {
  63                 BT_LIB_LOGE_APPEND_CAUSE("Failed to create array value.");
  64         } else {
  65                 BT_LOGD("Created attributes object: addr=%p",
  66                         attr_obj);
  67         }
  68
  69         return attr_obj;
  70 }
  71
  72 BT_HIDDEN
  73 void bt_attributes_destroy(struct bt_value *attr_obj)
  74 {
  75         BT_LOGD("Destroying attributes object: addr=%p", attr_obj);
  76         BT_OBJECT_PUT_REF_AND_RESET(attr_obj);
  77 }
  78
  79 BT_HIDDEN
  80 uint64_t bt_attributes_get_count(const struct bt_value *attr_obj)
  81 {
  82         return bt_value_array_get_length(attr_obj);
  83 }
  84
  85 BT_HIDDEN
  86 const char *bt_attributes_get_field_name(const struct bt_value *attr_obj,
  87                 uint64_t index)
  88 {
  89         const struct bt_value *attr_field_obj = NULL;
  90         const struct bt_value *attr_field_name_obj = NULL;
  91
  92         BT_ASSERT_DBG(attr_obj);
  93         BT_ASSERT_DBG(index < bt_value_array_get_length(attr_obj));
  94         attr_field_obj = bt_value_array_borrow_element_by_index_const(
  95                 attr_obj, index);
  96
  97         attr_field_name_obj =
  98                 bt_value_array_borrow_element_by_index_const(attr_field_obj,
  99                         BT_ATTR_NAME_INDEX);
 100
 101         return bt_value_string_get(attr_field_name_obj);
 102 }
 103
 104 BT_HIDDEN
 105 struct bt_value *bt_attributes_borrow_field_value(
 106                 struct bt_value *attr_obj, uint64_t index)
 107 {
 108         struct bt_value *attr_field_obj = NULL;
 109
 110         BT_ASSERT_DBG(attr_obj);
 111         BT_ASSERT_DBG(index < bt_value_array_get_length(attr_obj));
 112
 113         attr_field_obj =
 114                 bt_value_array_borrow_element_by_index(attr_obj, index);
 115
 116         return bt_value_array_borrow_element_by_index( attr_field_obj,
 117                 BT_ATTR_VALUE_INDEX);
 118 }
 119
 120 static
 121 struct bt_value *bt_attributes_borrow_field_by_name(
 122                 struct bt_value *attr_obj, const char *name)
 123 {
 124         uint64_t i, attr_size;
 125         struct bt_value *value_obj = NULL;
 126         struct bt_value *attr_field_name_obj = NULL;
 127
 128         attr_size = bt_value_array_get_length(attr_obj);
 129         for (i = 0; i < attr_size; ++i) {
 130                 const char *field_name;
 131
 132                 value_obj = bt_value_array_borrow_element_by_index(
 133                         attr_obj, i);
 134
 135                 attr_field_name_obj =
 136                         bt_value_array_borrow_element_by_index(
 137                                 value_obj, BT_ATTR_NAME_INDEX);
 138
 139                 field_name = bt_value_string_get(attr_field_name_obj);
 140
 141                 if (strcmp(field_name, name) == 0) {
 142                         break;
 143                 }
 144
 145                 value_obj = NULL;
 146         }
 147
 148         return value_obj;
 149 }
 150
 151 BT_HIDDEN
 152 int bt_attributes_set_field_value(struct bt_value *attr_obj,
 153                 const char *name, struct bt_value *value_obj)
 154 {
 155         int ret = 0;
 156         struct bt_value *attr_field_obj = NULL;
 157
 158         BT_ASSERT(attr_obj);
 159         BT_ASSERT(name);
 160         BT_ASSERT(value_obj);
 161         attr_field_obj = bt_attributes_borrow_field_by_name(attr_obj, name);
 162         if (attr_field_obj) {
 163                 ret = bt_value_array_set_element_by_index(
 164                         attr_field_obj, BT_ATTR_VALUE_INDEX,
 165                         value_obj);
 166                 attr_field_obj = NULL;
 167                 goto end;
 168         }
 169
 170         attr_field_obj = bt_value_array_create();
 171         if (!attr_field_obj) {
 172                 BT_LIB_LOGE_APPEND_CAUSE("Failed to create empty array value.");
 173                 ret = -1;
 174                 goto end;
 175         }
 176
 177         ret = bt_value_array_append_string_element(attr_field_obj,
 178                 name);
 179         ret |= bt_value_array_append_element(attr_field_obj,
 180                 value_obj);
 181         if (ret) {
 182                 BT_LIB_LOGE_APPEND_CAUSE(
 183                         "Cannot append elements to array value: %!+v",
 184                         attr_field_obj);
 185                 goto end;
 186         }
 187
 188         ret = bt_value_array_append_element(attr_obj,
 189                 attr_field_obj);
 190         if (ret) {
 191                 BT_LIB_LOGE_APPEND_CAUSE(
 192                         "Cannot append element to array value: "
 193                         "%![array-value-]+v, %![element-value-]+v",
 194                         attr_obj, attr_field_obj);
 195         }
 196
 197 end:
 198         bt_object_put_ref(attr_field_obj);
 199         return ret;
 200 }
 201
 202 BT_HIDDEN
 203 struct bt_value *bt_attributes_borrow_field_value_by_name(
 204                 struct bt_value *attr_obj, const char *name)
 205 {
 206         struct bt_value *value_obj = NULL;
 207         struct bt_value *attr_field_obj = NULL;
 208
 209         BT_ASSERT_DBG(attr_obj);
 210         BT_ASSERT_DBG(name);
 211         attr_field_obj = bt_attributes_borrow_field_by_name(attr_obj, name);
 212         if (!attr_field_obj) {
 213                 BT_LOGD("Cannot find attributes object's field by name: "
 214                         "value-addr=%p, name=\"%s\"", attr_obj, name);
 215                 goto end;
 216         }
 217
 218         value_obj = bt_value_array_borrow_element_by_index(
 219                 attr_field_obj, BT_ATTR_VALUE_INDEX);
 220
 221 end:
 222         return value_obj;
 223 }
 224
 225 BT_HIDDEN
 226 int bt_attributes_freeze(const struct bt_value *attr_obj)
 227 {
 228         uint64_t i, count;
 229         int ret = 0;
 230
 231         BT_ASSERT(attr_obj);
 232         BT_LOGD("Freezing attributes object: value-addr=%p", attr_obj);
 233
 234         count = bt_value_array_get_length(attr_obj);
 235
 236         /*
 237          * We do not freeze the array value object itself here, since
 238          * internal stuff could need to modify/add attributes. Each
 239          * attribute is frozen one by one.
 240          */
 241         for (i = 0; i < count; ++i) {
 242                 struct bt_value *obj = NULL;
 243
 244                 obj = bt_attributes_borrow_field_value(
 245                         (void *) attr_obj, i);
 246                 if (!obj) {
 247                         BT_LIB_LOGE_APPEND_CAUSE(
 248                                 "Cannot get attributes object's field value by index: "
 249                                 "%![value-]+v, index=%" PRIu64,
 250                                 attr_obj, i);
 251                         ret = -1;
 252                         goto end;
 253                 }
 254
 255                 bt_value_freeze(obj);
 256         }
 257
 258 end:
 259         return ret;
 260 }