ble_uuid.cpp

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#include "ble_uuid.h"
 
#ifdef USE_ESP32
#ifdef USE_ESP32_BLE_UUID
 
#include <cstring>
#include <cstdio>
#include <cinttypes>
#include "esphome/core/log.h"
#include "esphome/core/helpers.h"
 
namespace esphome::esp32_ble {
 
static const char *const TAG = "esp32_ble";
 
ESPBTUUID::ESPBTUUID() : uuid_() {}
ESPBTUUID ESPBTUUID::from_uint16(uint16_t uuid) {
  ESPBTUUID ret;
  ret.uuid_.len = ESP_UUID_LEN_16;
  ret.uuid_.uuid.uuid16 = uuid;
  return ret;
}
ESPBTUUID ESPBTUUID::from_uint32(uint32_t uuid) {
  ESPBTUUID ret;
  ret.uuid_.len = ESP_UUID_LEN_32;
  ret.uuid_.uuid.uuid32 = uuid;
  return ret;
}
ESPBTUUID ESPBTUUID::from_raw(const uint8_t *data) {
  ESPBTUUID ret;
  ret.uuid_.len = ESP_UUID_LEN_128;
  memcpy(ret.uuid_.uuid.uuid128, data, ESP_UUID_LEN_128);
  return ret;
}
ESPBTUUID ESPBTUUID::from_raw_reversed(const uint8_t *data) {
  ESPBTUUID ret;
  ret.uuid_.len = ESP_UUID_LEN_128;
  for (uint8_t i = 0; i < ESP_UUID_LEN_128; i++)
    ret.uuid_.uuid.uuid128[ESP_UUID_LEN_128 - 1 - i] = data[i];
  return ret;
}
ESPBTUUID ESPBTUUID::from_raw(const std::string &data) {
  ESPBTUUID ret;
  if (data.length() == 4) {
    ret.uuid_.len = ESP_UUID_LEN_16;
    ret.uuid_.uuid.uuid16 = 0;
    for (uint i = 0; i < data.length(); i += 2) {
      uint8_t msb = data.c_str()[i];
      uint8_t lsb = data.c_str()[i + 1];
      uint8_t lsb_shift = i <= 2 ? (2 - i) * 4 : 0;
 
      if (msb > '9')
        msb -= 7;
      if (lsb > '9')
        lsb -= 7;
      ret.uuid_.uuid.uuid16 += (((msb & 0x0F) << 4) | (lsb & 0x0F)) << lsb_shift;
    }
  } else if (data.length() == 8) {
    ret.uuid_.len = ESP_UUID_LEN_32;
    ret.uuid_.uuid.uuid32 = 0;
    for (uint i = 0; i < data.length(); i += 2) {
      uint8_t msb = data.c_str()[i];
      uint8_t lsb = data.c_str()[i + 1];
      uint8_t lsb_shift = i <= 6 ? (6 - i) * 4 : 0;
 
      if (msb > '9')
        msb -= 7;
      if (lsb > '9')
        lsb -= 7;
      ret.uuid_.uuid.uuid32 += (((msb & 0x0F) << 4) | (lsb & 0x0F)) << lsb_shift;
    }
  } else if (data.length() == 16) {  // how we can have 16 byte length string reprezenting 128 bit uuid??? needs to be
                                     // investigated (lack of time)
    ret.uuid_.len = ESP_UUID_LEN_128;
    memcpy(ret.uuid_.uuid.uuid128, (uint8_t *) data.data(), 16);
  } else if (data.length() == 36) {
    // If the length of the string is 36 bytes then we will assume it is a long hex string in
    // UUID format.
    ret.uuid_.len = ESP_UUID_LEN_128;
    int n = 0;
    for (uint i = 0; i < data.length(); i += 2) {
      if (data.c_str()[i] == '-')
        i++;
      uint8_t msb = data.c_str()[i];
      uint8_t lsb = data.c_str()[i + 1];
 
      if (msb > '9')
        msb -= 7;
      if (lsb > '9')
        lsb -= 7;
      ret.uuid_.uuid.uuid128[15 - n++] = ((msb & 0x0F) << 4) | (lsb & 0x0F);
    }
  } else {
    ESP_LOGE(TAG, "ERROR: UUID value not 2, 4, 16 or 36 bytes - %s", data.c_str());
  }
  return ret;
}
ESPBTUUID ESPBTUUID::from_uuid(esp_bt_uuid_t uuid) {
  ESPBTUUID ret;
  ret.uuid_.len = uuid.len;
  if (uuid.len == ESP_UUID_LEN_16) {
    ret.uuid_.uuid.uuid16 = uuid.uuid.uuid16;
  } else if (uuid.len == ESP_UUID_LEN_32) {
    ret.uuid_.uuid.uuid32 = uuid.uuid.uuid32;
  } else if (uuid.len == ESP_UUID_LEN_128) {
    memcpy(ret.uuid_.uuid.uuid128, uuid.uuid.uuid128, ESP_UUID_LEN_128);
  }
  return ret;
}
ESPBTUUID ESPBTUUID::as_128bit() const {
  if (this->uuid_.len == ESP_UUID_LEN_128) {
    return *this;
  }
  uint8_t data[] = {0xFB, 0x34, 0x9B, 0x5F, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
  uint32_t uuid32;
  if (this->uuid_.len == ESP_UUID_LEN_32) {
    uuid32 = this->uuid_.uuid.uuid32;
  } else {
    uuid32 = this->uuid_.uuid.uuid16;
  }
  for (uint8_t i = 0; i < this->uuid_.len; i++) {
    data[12 + i] = ((uuid32 >> i * 8) & 0xFF);
  }
  return ESPBTUUID::from_raw(data);
}
bool ESPBTUUID::contains(uint8_t data1, uint8_t data2) const {
  if (this->uuid_.len == ESP_UUID_LEN_16) {
    return (this->uuid_.uuid.uuid16 >> 8) == data2 && (this->uuid_.uuid.uuid16 & 0xFF) == data1;
  } else if (this->uuid_.len == ESP_UUID_LEN_32) {
    for (uint8_t i = 0; i < 3; i++) {
      bool a = ((this->uuid_.uuid.uuid32 >> i * 8) & 0xFF) == data1;
      bool b = ((this->uuid_.uuid.uuid32 >> (i + 1) * 8) & 0xFF) == data2;
      if (a && b)
        return true;
    }
  } else {
    for (uint8_t i = 0; i < 15; i++) {
      if (this->uuid_.uuid.uuid128[i] == data1 && this->uuid_.uuid.uuid128[i + 1] == data2)
        return true;
    }
  }
  return false;
}
bool ESPBTUUID::operator==(const ESPBTUUID &uuid) const {
  if (this->uuid_.len == uuid.uuid_.len) {
    switch (this->uuid_.len) {
      case ESP_UUID_LEN_16:
        if (uuid.uuid_.uuid.uuid16 == this->uuid_.uuid.uuid16) {
          return true;
        }
        break;
      case ESP_UUID_LEN_32:
        if (uuid.uuid_.uuid.uuid32 == this->uuid_.uuid.uuid32) {
          return true;
        }
        break;
      case ESP_UUID_LEN_128:
        for (uint8_t i = 0; i < ESP_UUID_LEN_128; i++) {
          if (uuid.uuid_.uuid.uuid128[i] != this->uuid_.uuid.uuid128[i]) {
            return false;
          }
        }
        return true;
        break;
    }
  } else {
    return this->as_128bit() == uuid.as_128bit();
  }
  return false;
}
esp_bt_uuid_t ESPBTUUID::get_uuid() const { return this->uuid_; }
std::string ESPBTUUID::to_string() const {
  char buf[40];  // Enough for 128-bit UUID with dashes
  char *pos = buf;
 
  switch (this->uuid_.len) {
    case ESP_UUID_LEN_16:
      *pos++ = '0';
      *pos++ = 'x';
      *pos++ = format_hex_pretty_char(this->uuid_.uuid.uuid16 >> 12);
      *pos++ = format_hex_pretty_char((this->uuid_.uuid.uuid16 >> 8) & 0x0F);
      *pos++ = format_hex_pretty_char((this->uuid_.uuid.uuid16 >> 4) & 0x0F);
      *pos++ = format_hex_pretty_char(this->uuid_.uuid.uuid16 & 0x0F);
      *pos = '\0';
      return std::string(buf);
 
    case ESP_UUID_LEN_32:
      *pos++ = '0';
      *pos++ = 'x';
      for (int shift = 28; shift >= 0; shift -= 4) {
        *pos++ = format_hex_pretty_char((this->uuid_.uuid.uuid32 >> shift) & 0x0F);
      }
      *pos = '\0';
      return std::string(buf);
 
    default:
    case ESP_UUID_LEN_128:
      // Format: XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX
      for (int8_t i = 15; i >= 0; i--) {
        uint8_t byte = this->uuid_.uuid.uuid128[i];
        *pos++ = format_hex_pretty_char(byte >> 4);
        *pos++ = format_hex_pretty_char(byte & 0x0F);
        if (i == 12 || i == 10 || i == 8 || i == 6) {
          *pos++ = '-';
        }
      }
      *pos = '\0';
      return std::string(buf);
  }
  return "";
}
 
}  // namespace esphome::esp32_ble
 
#endif  // USE_ESP32_BLE_UUID
#endif  // USE_ESP32