src/lib/trace-ir/attributes.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright (c) 2015 EfficiOS Inc. and Linux Foundation
   5  * Copyright (c) 2015 Philippe Proulx <pproulx@efficios.com>
   6  */
   7
   8 #define BT_LOG_TAG "LIB/ATTRS"
   9 #include "lib/logging.h"
  10
  11 #include "common/macros.h"
  12 #include <babeltrace2/value.h>
  13 #include "lib/assert-cond.h"
  14 #include "lib/object.h"
  15 #include <babeltrace2/value.h>
  16 #include "lib/value.h"
  17 #include "attributes.h"
  18 #include <inttypes.h>
  19 #include "compat/string.h"
  20 #include "common/assert.h"
  21
  22 #define BT_ATTR_NAME_INDEX              0
  23 #define BT_ATTR_VALUE_INDEX             1
  24
  25 struct bt_value *bt_attributes_create(void)
  26 {
  27         struct bt_value *attr_obj;
  28
  29         /*
  30          * Attributes: array value object of array value objects, each one
  31          * containing two entries: a string value object (attributes
  32          * field name), and a value object (attributes field value).
  33          *
  34          * Example (JSON representation):
  35          *
  36          *     [
  37          *         ["hostname", "eeppdesk"],
  38          *         ["sysname", "Linux"],
  39          *         ["tracer_major", 2],
  40          *         ["tracer_minor", 5]
  41          *     ]
  42          */
  43         BT_LOGD_STR("Creating attributes object.");
  44         attr_obj = bt_value_array_create();
  45         if (!attr_obj) {
  46                 BT_LIB_LOGE_APPEND_CAUSE("Failed to create array value.");
  47         } else {
  48                 BT_LOGD("Created attributes object: addr=%p",
  49                         attr_obj);
  50         }
  51
  52         return attr_obj;
  53 }
  54
  55 void bt_attributes_destroy(struct bt_value *attr_obj)
  56 {
  57         BT_LOGD("Destroying attributes object: addr=%p", attr_obj);
  58         BT_OBJECT_PUT_REF_AND_RESET(attr_obj);
  59 }
  60
  61 uint64_t bt_attributes_get_count(const struct bt_value *attr_obj)
  62 {
  63         return bt_value_array_get_length(attr_obj);
  64 }
  65
  66 const char *bt_attributes_get_field_name(const struct bt_value *attr_obj,
  67                 uint64_t index)
  68 {
  69         const struct bt_value *attr_field_obj = NULL;
  70         const struct bt_value *attr_field_name_obj = NULL;
  71
  72         BT_ASSERT_DBG(attr_obj);
  73         BT_ASSERT_DBG(index < bt_value_array_get_length(attr_obj));
  74         attr_field_obj = bt_value_array_borrow_element_by_index_const(
  75                 attr_obj, index);
  76
  77         attr_field_name_obj =
  78                 bt_value_array_borrow_element_by_index_const(attr_field_obj,
  79                         BT_ATTR_NAME_INDEX);
  80
  81         return bt_value_string_get(attr_field_name_obj);
  82 }
  83
  84 struct bt_value *bt_attributes_borrow_field_value(
  85                 struct bt_value *attr_obj, uint64_t index)
  86 {
  87         struct bt_value *attr_field_obj = NULL;
  88
  89         BT_ASSERT_DBG(attr_obj);
  90         BT_ASSERT_DBG(index < bt_value_array_get_length(attr_obj));
  91
  92         attr_field_obj =
  93                 bt_value_array_borrow_element_by_index(attr_obj, index);
  94
  95         return bt_value_array_borrow_element_by_index( attr_field_obj,
  96                 BT_ATTR_VALUE_INDEX);
  97 }
  98
  99 static
 100 struct bt_value *bt_attributes_borrow_field_by_name(
 101                 struct bt_value *attr_obj, const char *name)
 102 {
 103         uint64_t i, attr_size;
 104         struct bt_value *value_obj = NULL;
 105         struct bt_value *attr_field_name_obj = NULL;
 106
 107         attr_size = bt_value_array_get_length(attr_obj);
 108         for (i = 0; i < attr_size; ++i) {
 109                 const char *field_name;
 110
 111                 value_obj = bt_value_array_borrow_element_by_index(
 112                         attr_obj, i);
 113
 114                 attr_field_name_obj =
 115                         bt_value_array_borrow_element_by_index(
 116                                 value_obj, BT_ATTR_NAME_INDEX);
 117
 118                 field_name = bt_value_string_get(attr_field_name_obj);
 119
 120                 if (strcmp(field_name, name) == 0) {
 121                         break;
 122                 }
 123
 124                 value_obj = NULL;
 125         }
 126
 127         return value_obj;
 128 }
 129
 130 int bt_attributes_set_field_value(struct bt_value *attr_obj,
 131                 const char *name, struct bt_value *value_obj)
 132 {
 133         int ret = 0;
 134         struct bt_value *attr_field_obj = NULL;
 135
 136         BT_ASSERT(attr_obj);
 137         BT_ASSERT(name);
 138         BT_ASSERT(value_obj);
 139         attr_field_obj = bt_attributes_borrow_field_by_name(attr_obj, name);
 140         if (attr_field_obj) {
 141                 ret = bt_value_array_set_element_by_index(
 142                         attr_field_obj, BT_ATTR_VALUE_INDEX,
 143                         value_obj);
 144                 attr_field_obj = NULL;
 145                 goto end;
 146         }
 147
 148         attr_field_obj = bt_value_array_create();
 149         if (!attr_field_obj) {
 150                 BT_LIB_LOGE_APPEND_CAUSE("Failed to create empty array value.");
 151                 ret = -1;
 152                 goto end;
 153         }
 154
 155         ret = bt_value_array_append_string_element(attr_field_obj,
 156                 name);
 157         ret |= bt_value_array_append_element(attr_field_obj,
 158                 value_obj);
 159         if (ret) {
 160                 BT_LIB_LOGE_APPEND_CAUSE(
 161                         "Cannot append elements to array value: %!+v",
 162                         attr_field_obj);
 163                 goto end;
 164         }
 165
 166         ret = bt_value_array_append_element(attr_obj,
 167                 attr_field_obj);
 168         if (ret) {
 169                 BT_LIB_LOGE_APPEND_CAUSE(
 170                         "Cannot append element to array value: "
 171                         "%![array-value-]+v, %![element-value-]+v",
 172                         attr_obj, attr_field_obj);
 173         }
 174
 175 end:
 176         bt_object_put_ref(attr_field_obj);
 177         return ret;
 178 }
 179
 180 struct bt_value *bt_attributes_borrow_field_value_by_name(
 181                 struct bt_value *attr_obj, const char *name)
 182 {
 183         struct bt_value *value_obj = NULL;
 184         struct bt_value *attr_field_obj = NULL;
 185
 186         BT_ASSERT_DBG(attr_obj);
 187         BT_ASSERT_DBG(name);
 188         attr_field_obj = bt_attributes_borrow_field_by_name(attr_obj, name);
 189         if (!attr_field_obj) {
 190                 BT_LOGD("Cannot find attributes object's field by name: "
 191                         "value-addr=%p, name=\"%s\"", attr_obj, name);
 192                 goto end;
 193         }
 194
 195         value_obj = bt_value_array_borrow_element_by_index(
 196                 attr_field_obj, BT_ATTR_VALUE_INDEX);
 197
 198 end:
 199         return value_obj;
 200 }
 201
 202 int bt_attributes_freeze(const struct bt_value *attr_obj)
 203 {
 204         uint64_t i, count;
 205         int ret = 0;
 206
 207         BT_ASSERT(attr_obj);
 208         BT_LOGD("Freezing attributes object: value-addr=%p", attr_obj);
 209
 210         count = bt_value_array_get_length(attr_obj);
 211
 212         /*
 213          * We do not freeze the array value object itself here, since
 214          * internal stuff could need to modify/add attributes. Each
 215          * attribute is frozen one by one.
 216          */
 217         for (i = 0; i < count; ++i) {
 218                 struct bt_value *obj = NULL;
 219
 220                 obj = bt_attributes_borrow_field_value(
 221                         (void *) attr_obj, i);
 222                 if (!obj) {
 223                         BT_LIB_LOGE_APPEND_CAUSE(
 224                                 "Cannot get attributes object's field value by index: "
 225                                 "%![value-]+v, index=%" PRIu64,
 226                                 attr_obj, i);
 227                         ret = -1;
 228                         goto end;
 229                 }
 230
 231                 bt_value_freeze(obj);
 232         }
 233
 234 end:
 235         return ret;
 236 }