1 files changed, 37 insertions, 29 deletions

diff --git a/src/util/strencodings.h b/src/util/strencodings.h
index 1f83fa3ffa..ebb6d88952 100644
--- a/src/util/strencodings.h
+++ b/src/util/strencodings.h
@@ -54,24 +54,21 @@ enum class ByteUnit : uint64_t {
 * @param[in] rule   The set of safe chars to choose (default: least restrictive)
 * @return           A new string without unsafe chars
 */
-std::string SanitizeString(const std::string& str, int rule = SAFE_CHARS_DEFAULT);
-std::vector<unsigned char> ParseHex(const char* psz);
-std::vector<unsigned char> ParseHex(const std::string& str);
+std::string SanitizeString(std::string_view str, int rule = SAFE_CHARS_DEFAULT);
+std::vector<unsigned char> ParseHex(std::string_view str);
 signed char HexDigit(char c);
 /* Returns true if each character in str is a hex character, and has an even
  * number of hex digits.*/
-bool IsHex(const std::string& str);
+bool IsHex(std::string_view str);
 /**
 * Return true if the string is a hex number, optionally prefixed with "0x"
 */
-bool IsHexNumber(const std::string& str);
-std::vector<unsigned char> DecodeBase64(const char* p, bool* pf_invalid = nullptr);
-std::string DecodeBase64(const std::string& str, bool* pf_invalid = nullptr);
+bool IsHexNumber(std::string_view str);
+std::optional<std::vector<unsigned char>> DecodeBase64(std::string_view str);
 std::string EncodeBase64(Span<const unsigned char> input);
 inline std::string EncodeBase64(Span<const std::byte> input) { return EncodeBase64(MakeUCharSpan(input)); }
-inline std::string EncodeBase64(const std::string& str) { return EncodeBase64(MakeUCharSpan(str)); }
-std::vector<unsigned char> DecodeBase32(const char* p, bool* pf_invalid = nullptr);
-std::string DecodeBase32(const std::string& str, bool* pf_invalid = nullptr);
+inline std::string EncodeBase64(std::string_view str) { return EncodeBase64(MakeUCharSpan(str)); }
+std::optional<std::vector<unsigned char>> DecodeBase32(std::string_view str);
 
 /**
  * Base32 encode.
@@ -85,9 +82,9 @@ std::string EncodeBase32(Span<const unsigned char> input, bool pad = true);
  * If `pad` is true, then the output will be padded with '=' so that its length
  * is a multiple of 8.
  */
-std::string EncodeBase32(const std::string& str, bool pad = true);
+std::string EncodeBase32(std::string_view str, bool pad = true);
 
-void SplitHostPort(std::string in, uint16_t& portOut, std::string& hostOut);
+void SplitHostPort(std::string_view in, uint16_t& portOut, std::string& hostOut);
 
 // LocaleIndependentAtoi is provided for backwards compatibility reasons.
 //
@@ -101,12 +98,12 @@ void SplitHostPort(std::string in, uint16_t& portOut, std::string& hostOut);
 // undefined behavior, while this function returns the maximum or minimum
 // values, respectively.
 template <typename T>
-T LocaleIndependentAtoi(const std::string& str)
+T LocaleIndependentAtoi(std::string_view str)
 {
     static_assert(std::is_integral<T>::value);
     T result;
     // Emulate atoi(...) handling of white space and leading +/-.
-    std::string s = TrimString(str);
+    std::string_view s = TrimStringView(str);
     if (!s.empty() && s[0] == '+') {
         if (s.length() >= 2 && s[1] == '-') {
             return 0;
@@ -162,7 +159,7 @@ constexpr inline bool IsSpace(char c) noexcept {
  *   parsed value is not in the range representable by the type T.
  */
 template <typename T>
-std::optional<T> ToIntegral(const std::string& str)
+std::optional<T> ToIntegral(std::string_view str)
 {
     static_assert(std::is_integral<T>::value);
     T result;
@@ -178,42 +175,42 @@ std::optional<T> ToIntegral(const std::string& str)
  * @returns true if the entire string could be parsed as valid integer,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-[[nodiscard]] bool ParseInt32(const std::string& str, int32_t *out);
+[[nodiscard]] bool ParseInt32(std::string_view str, int32_t *out);
 
 /**
  * Convert string to signed 64-bit integer with strict parse error feedback.
  * @returns true if the entire string could be parsed as valid integer,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-[[nodiscard]] bool ParseInt64(const std::string& str, int64_t *out);
+[[nodiscard]] bool ParseInt64(std::string_view str, int64_t *out);
 
 /**
  * Convert decimal string to unsigned 8-bit integer with strict parse error feedback.
  * @returns true if the entire string could be parsed as valid integer,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-[[nodiscard]] bool ParseUInt8(const std::string& str, uint8_t *out);
+[[nodiscard]] bool ParseUInt8(std::string_view str, uint8_t *out);
 
 /**
  * Convert decimal string to unsigned 16-bit integer with strict parse error feedback.
  * @returns true if the entire string could be parsed as valid integer,
  *   false if the entire string could not be parsed or if overflow or underflow occurred.
  */
-[[nodiscard]] bool ParseUInt16(const std::string& str, uint16_t* out);
+[[nodiscard]] bool ParseUInt16(std::string_view str, uint16_t* out);
 
 /**
  * Convert decimal string to unsigned 32-bit integer with strict parse error feedback.
  * @returns true if the entire string could be parsed as valid integer,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-[[nodiscard]] bool ParseUInt32(const std::string& str, uint32_t *out);
+[[nodiscard]] bool ParseUInt32(std::string_view str, uint32_t *out);
 
 /**
  * Convert decimal string to unsigned 64-bit integer with strict parse error feedback.
  * @returns true if the entire string could be parsed as valid integer,
  *   false if not the entire string could be parsed or when overflow or underflow occurred.
  */
-[[nodiscard]] bool ParseUInt64(const std::string& str, uint64_t *out);
+[[nodiscard]] bool ParseUInt64(std::string_view str, uint64_t *out);
 
 /**
  * Convert a span of bytes to a lower-case hexadecimal string.
@@ -226,7 +223,7 @@ inline std::string HexStr(const Span<const std::byte> s) { return HexStr(MakeUCh
  * Format a paragraph of text to a fixed width, adding spaces for
  * indentation to any added line.
  */
-std::string FormatParagraph(const std::string& in, size_t width = 79, size_t indent = 0);
+std::string FormatParagraph(std::string_view in, size_t width = 79, size_t indent = 0);
 
 /**
  * Timing-attack-resistant comparison.
@@ -248,17 +245,28 @@ bool TimingResistantEqual(const T& a, const T& b)
  * @returns true on success, false on error.
  * @note The result must be in the range (-10^18,10^18), otherwise an overflow error will trigger.
  */
-[[nodiscard]] bool ParseFixedPoint(const std::string &val, int decimals, int64_t *amount_out);
+[[nodiscard]] bool ParseFixedPoint(std::string_view, int decimals, int64_t *amount_out);
+
+namespace {
+/** Helper class for the default infn argument to ConvertBits (just returns the input). */
+struct IntIdentity
+{
+    [[maybe_unused]] int operator()(int x) const { return x; }
+};
+
+} // namespace
 
 /** Convert from one power-of-2 number base to another. */
-template<int frombits, int tobits, bool pad, typename O, typename I>
-bool ConvertBits(const O& outfn, I it, I end) {
+template<int frombits, int tobits, bool pad, typename O, typename It, typename I = IntIdentity>
+bool ConvertBits(O outfn, It it, It end, I infn = {}) {
     size_t acc = 0;
     size_t bits = 0;
     constexpr size_t maxv = (1 << tobits) - 1;
     constexpr size_t max_acc = (1 << (frombits + tobits - 1)) - 1;
     while (it != end) {
-        acc = ((acc << frombits) | *it) & max_acc;
+        int v = infn(*it);
+        if (v < 0) return false;
+        acc = ((acc << frombits) | v) & max_acc;
         bits += frombits;
         while (bits >= tobits) {
             bits -= tobits;
@@ -298,7 +306,7 @@ constexpr char ToLower(char c)
  * @param[in] str   the string to convert to lowercase.
  * @returns         lowercased equivalent of str
  */
-std::string ToLower(const std::string& str);
+std::string ToLower(std::string_view str);
 
 /**
  * Converts the given character to its uppercase equivalent.
@@ -324,7 +332,7 @@ constexpr char ToUpper(char c)
  * @param[in] str   the string to convert to uppercase.
  * @returns         UPPERCASED EQUIVALENT OF str
  */
-std::string ToUpper(const std::string& str);
+std::string ToUpper(std::string_view str);
 
 /**
  * Capitalizes the first character of the given string.
@@ -348,6 +356,6 @@ std::string Capitalize(std::string str);
  * @returns                        optional uint64_t bytes from str or nullopt
  *                                 if ToIntegral is false, str is empty, trailing whitespace or overflow
  */
-std::optional<uint64_t> ParseByteUnits(const std::string& str, ByteUnit default_multiplier);
+std::optional<uint64_t> ParseByteUnits(std::string_view str, ByteUnit default_multiplier);
 
 #endif // BITCOIN_UTIL_STRENCODINGS_H