From e0a21cf702179ed7a2f66f12efedf61e8ec03c74 Mon Sep 17 00:00:00 2001
From: orignal <i2porignal@yandex.ru>
Date: Sun, 16 Mar 2025 20:40:36 -0400
Subject: [PATCH] use string/string_view for base32

---
 libi2pd/Base.cpp     | 24 ++++++++++++------------
 libi2pd/Base.h       |  5 +++--
 libi2pd/Blinding.cpp |  7 +++----
 libi2pd/Tag.h        |  6 ++----
 4 files changed, 20 insertions(+), 22 deletions(-)

diff --git a/libi2pd/Base.cpp b/libi2pd/Base.cpp
index 719cdec3..dc331e3e 100644
--- a/libi2pd/Base.cpp
+++ b/libi2pd/Base.cpp
@@ -261,13 +261,12 @@ namespace data
 		iT64[(int)P64] = 0;
 	}
 
-	size_t Base32ToByteStream (const char * inBuf, size_t len, uint8_t * outBuf, size_t outLen)
+	size_t Base32ToByteStream (std::string_view base32Str, uint8_t * outBuf, size_t outLen)
 	{
 		unsigned int tmp = 0, bits = 0;
 		size_t ret = 0;
-		for (size_t i = 0; i < len; i++)
+		for (auto ch: base32Str)
 		{
-			char ch = inBuf[i];
 			if (ch >= '2' && ch <= '7') // digit
 				ch = (ch - '2') + 26; // 26 means a-z
 			else if (ch >= 'a' && ch <= 'z')
@@ -287,13 +286,15 @@ namespace data
 			tmp <<= 5;
 		}
 		return ret;
-	}
-
-	size_t ByteStreamToBase32 (const uint8_t * inBuf, size_t len, char * outBuf, size_t outLen)
+	}	
+	
+	std::string ByteStreamToBase32 (const uint8_t * inBuf, size_t len)
 	{
-		size_t ret = 0, pos = 1;
+		std::string out;
+		out.reserve ((len * 8 + 4) / 5);
+		size_t pos = 1;
 		unsigned int bits = 8, tmp = inBuf[0];
-		while (ret < outLen && (bits > 0 || pos < len))
+		while (bits > 0 || pos < len)
 		{
 			if (bits < 5)
 			{
@@ -313,10 +314,9 @@ namespace data
 
 			bits -= 5;
 			int ind = (tmp >> bits) & 0x1F;
-			outBuf[ret] = (ind < 26) ? (ind + 'a') : ((ind - 26) + '2');
-			ret++;
+			out.push_back ((ind < 26) ? (ind + 'a') : ((ind - 26) + '2'));
 		}
-		return ret;
-	}
+		return out;
+	}	
 }
 }
diff --git a/libi2pd/Base.h b/libi2pd/Base.h
index 25a4e7aa..3bdbe211 100644
--- a/libi2pd/Base.h
+++ b/libi2pd/Base.h
@@ -27,8 +27,9 @@ namespace data
 		return (ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z') || (ch >= '0' && ch <= '9') || ch == '-' || ch == '~';
 	}	
 
-	size_t Base32ToByteStream (const char * inBuf, size_t len, uint8_t * outBuf, size_t outLen);
-	size_t ByteStreamToBase32 (const uint8_t * InBuf, size_t len, char * outBuf, size_t outLen);
+	size_t Base32ToByteStream (std::string_view base32Str, uint8_t * outBuf, size_t outLen);
+	std::string ByteStreamToBase32 (const uint8_t * inBuf, size_t len);
+	
 	constexpr bool IsBase32 (char ch)
 	{
 		return (ch >= 'a' && ch <= 'z') || (ch >= '2' && ch <= '7');
diff --git a/libi2pd/Blinding.cpp b/libi2pd/Blinding.cpp
index 5266a6eb..a661b428 100644
--- a/libi2pd/Blinding.cpp
+++ b/libi2pd/Blinding.cpp
@@ -156,7 +156,7 @@ namespace data
 		m_SigType (0) // 0 means invalid, we can't blind DSA, set it later
 	{
 		uint8_t addr[40]; // TODO: define length from b33
-		size_t l = i2p::data::Base32ToByteStream (b33.data (), b33.length (), addr, 40);
+		size_t l = i2p::data::Base32ToByteStream (b33, addr, 40);
 		if (l < 32)
 		{
 			LogPrint (eLogError, "Blinding: Malformed b33 ", b33);
@@ -198,7 +198,7 @@ namespace data
 	std::string BlindedPublicKey::ToB33 () const
 	{
 		if (m_PublicKey.size () > 32) return ""; // assume 25519
-		uint8_t addr[35]; char str[60]; // TODO: define actual length
+		uint8_t addr[35];
 		uint8_t flags = 0;
 		if (m_IsClientAuth) flags |= B33_PER_CLIENT_AUTH_FLAG;
 		addr[0] = flags; // flags
@@ -208,8 +208,7 @@ namespace data
 		uint32_t checksum = crc32 (0, addr + 3, m_PublicKey.size ());
 		// checksum is Little Endian
 		addr[0] ^= checksum; addr[1] ^= (checksum >> 8); addr[2] ^= (checksum >> 16);
-		auto l = ByteStreamToBase32 (addr, m_PublicKey.size () + 3, str, 60);
-		return std::string (str, str + l);
+		return ByteStreamToBase32 (addr, m_PublicKey.size () + 3);
 	}
 
 	void BlindedPublicKey::GetCredential (uint8_t * credential) const
diff --git a/libi2pd/Tag.h b/libi2pd/Tag.h
index 92dfd090..af2de154 100644
--- a/libi2pd/Tag.h
+++ b/libi2pd/Tag.h
@@ -69,14 +69,12 @@ namespace data
 
 			std::string ToBase32 (size_t len = sz) const
 			{
-				char str[sz*2];
-				size_t l = i2p::data::ByteStreamToBase32 (m_Buf, len, str, sz*2);
-				return std::string (str, str + l);
+				return i2p::data::ByteStreamToBase32 (m_Buf, len);
 			}
 
 			size_t FromBase32 (std::string_view s)
 			{
-				return i2p::data::Base32ToByteStream (s.data (), s.length (), m_Buf, sz);
+				return i2p::data::Base32ToByteStream (s, m_Buf, sz);
 			}
 
 			size_t FromBase64 (std::string_view s)