.. _program_listing_file_components_Util_src_Hex.cpp: Program Listing for File Hex.cpp ================================ |exhale_lsh| :ref:`Return to documentation for file ` (``components/Util/src/Hex.cpp``) .. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS .. code-block:: cpp #include "Hex.h" namespace util { esp_err_t hexToInt(const char c, int& r) { if (c >= '0' && c <= '9') { r = c - '0'; return ESP_OK; } if (c >= 'A' && c <= 'F') { r = c - 'A' + 10; return ESP_OK; } if (c >= 'a' && c <= 'f') { r = c - 'a' + 10; return ESP_OK; } return ESP_FAIL; } esp_err_t hexToBytes(const char* src, std::uint8_t* target) { esp_err_t err; while (src[0] != '\0' && src[1] != '\0') { int digit0 = 0; int digit1 = 0; err = hexToInt(src[0], digit0); if (err != ESP_OK) return err; err = hexToInt(src[1], digit1); if (err != ESP_OK) return err; target[0] = static_cast((digit0 * 16) + digit1); target += 1; src += 2; } return ESP_OK; } esp_err_t bytesToHex(std::uint8_t* buf, char* dst, std::size_t len) { static const char hexmap[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'}; for (size_t i = 0; i < len; i++) { const uint8_t upper = (buf[i] & 0xf0) >> 4; const uint8_t lower = (buf[i] & 0x0f); dst[i * 2] = hexmap[upper]; dst[i * 2 + 1] = hexmap[lower]; } dst[len * 2] = '\0'; return ESP_OK; } } // namespace util