Fix some warnings noticed by the readability-* clang-tidy checkers.

55 files changed, 128 insertions, 131 deletions

diff --git a/src/modules/extra/m_argon2.cpp b/src/modules/extra/m_argon2.cpp
index 57e2d895d..e972939fe 100644
--- a/src/modules/extra/m_argon2.cpp
+++ b/src/modules/extra/m_argon2.cpp
@@ -137,9 +137,9 @@ public:
 			data.length(),
 			salt.c_str(),
 			salt.length(),
-			&raw_data[0],
+			raw_data.data(),
 			raw_data.size(),
-			&encoded_data[0],
+			encoded_data.data(),
 			encoded_data.size(),
 			argon2Type,
 			config.version);
@@ -152,7 +152,7 @@ public:
 		// to do anything useful with them if we don't encode them.
 		// So we pretend this is the raw version, and instead make
 		// ToPrintable return its input.
-		return std::string(&encoded_data[0], encoded_data.size());
+		return std::string(encoded_data.data(), encoded_data.size());
 	}
 
 	std::string ToPrintable(const std::string& raw) override
diff --git a/src/modules/extra/m_log_syslog.cpp b/src/modules/extra/m_log_syslog.cpp
index a3cf23ec6..62d08e45e 100644
--- a/src/modules/extra/m_log_syslog.cpp
+++ b/src/modules/extra/m_log_syslog.cpp
@@ -26,7 +26,7 @@ class SyslogMethod final
 {
 private:
 	// Converts an InspIRCd log level to syslog priority.
-	int LevelToPriority(Log::Level level)
+	static int LevelToPriority(Log::Level level)
 	{
 		switch (level)
 		{
diff --git a/src/modules/extra/m_mysql.cpp b/src/modules/extra/m_mysql.cpp
index c76034cc1..51fdef06c 100644
--- a/src/modules/extra/m_mysql.cpp
+++ b/src/modules/extra/m_mysql.cpp
@@ -269,7 +269,7 @@ class SQLConnection final
 	: public SQL::Provider
 {
 private:
-	bool EscapeString(SQL::Query* query, const std::string& in, std::string& out)
+	bool EscapeString(SQL::Query* query, const std::string& in, std::string& out) const
 	{
 		// In the worst case each character may need to be encoded as using two bytes and one
 		// byte is the NUL terminator.
@@ -281,7 +281,7 @@ private:
 		// Unfortunately, someone genius decided that mysql_escape_string should return an
 		// unsigned type even though -1 is returned on error so checking whether an error
 		// happened is a bit cursed.
-		unsigned long escapedsize = mysql_escape_string(&buffer[0], in.c_str(), in.length());
+		unsigned long escapedsize = mysql_escape_string(buffer.data(), in.c_str(), in.length());
 		if (escapedsize == static_cast<unsigned long>(-1))
 		{
 			SQL::Error err(SQL::QSEND_FAIL, InspIRCd::Format("%u: %s", mysql_errno(connection), mysql_error(connection)));
@@ -289,7 +289,7 @@ private:
 			return false;
 		}
 
-		out.append(&buffer[0], escapedsize);
+		out.append(buffer.data(), escapedsize);
 		return true;
 	}
 
diff --git a/src/modules/extra/m_pgsql.cpp b/src/modules/extra/m_pgsql.cpp
index ad3743ad9..e388f377f 100644
--- a/src/modules/extra/m_pgsql.cpp
+++ b/src/modules/extra/m_pgsql.cpp
@@ -446,10 +446,10 @@ restart:
 					std::string parm = p[param++];
 					std::vector<char> buffer(parm.length() * 2 + 1);
 					int error;
-					size_t escapedsize = PQescapeStringConn(sql, &buffer[0], parm.data(), parm.length(), &error);
+					size_t escapedsize = PQescapeStringConn(sql, buffer.data(), parm.data(), parm.length(), &error);
 					if (error)
 						ServerInstance->Logs.Debug(MODNAME, "BUG: Apparently PQescapeStringConn() failed");
-					res.append(&buffer[0], escapedsize);
+					res.append(buffer.data(), escapedsize);
 				}
 			}
 		}
@@ -477,10 +477,10 @@ restart:
 					std::string parm = it->second;
 					std::vector<char> buffer(parm.length() * 2 + 1);
 					int error;
-					size_t escapedsize = PQescapeStringConn(sql, &buffer[0], parm.data(), parm.length(), &error);
+					size_t escapedsize = PQescapeStringConn(sql, buffer.data(), parm.data(), parm.length(), &error);
 					if (error)
 						ServerInstance->Logs.Debug(MODNAME, "BUG: Apparently PQescapeStringConn() failed");
-					res.append(&buffer[0], escapedsize);
+					res.append(buffer.data(), escapedsize);
 				}
 			}
 		}
diff --git a/src/modules/extra/m_regex_posix.cpp b/src/modules/extra/m_regex_posix.cpp
index 819046e2b..7476039cd 100644
--- a/src/modules/extra/m_regex_posix.cpp
+++ b/src/modules/extra/m_regex_posix.cpp
@@ -51,10 +51,10 @@ public:
 		std::vector<char> errormsg(errorsize);
 
 		// Retrieve the error message and free the buffer.
-		regerror(error, &regex, &errormsg[0], errormsg.size());
+		regerror(error, &regex, errormsg.data(), errormsg.size());
 		regfree(&regex);
 
-		throw Regex::Exception(mod, pattern, std::string(&errormsg[0], errormsg.size() - 1));
+		throw Regex::Exception(mod, pattern, std::string(errormsg.data(), errormsg.size() - 1));
 	}
 
 	~POSIXPattern() override
@@ -70,7 +70,7 @@ public:
 	std::optional<Regex::MatchCollection> Matches(const std::string& text) override
 	{
 		std::vector<regmatch_t> matches(32);
-		int result = regexec(&regex, text.c_str(), matches.size(), &matches[0], 0);
+		int result = regexec(&regex, text.c_str(), matches.size(), matches.data(), 0);
 		if (result)
 			return std::nullopt;
 
diff --git a/src/modules/extra/m_regex_re2.cpp b/src/modules/extra/m_regex_re2.cpp
index 068be5049..7874564cc 100644
--- a/src/modules/extra/m_regex_re2.cpp
+++ b/src/modules/extra/m_regex_re2.cpp
@@ -37,7 +37,7 @@ class RE2Pattern final
 private:
 	RE2 regex;
 
-	RE2::Options BuildOptions(uint8_t options)
+	static RE2::Options BuildOptions(uint8_t options)
 	{
 		RE2::Options re2options;
 		re2options.set_case_sensitive(!(options & Regex::OPT_CASE_INSENSITIVE));
@@ -62,7 +62,7 @@ public:
 	std::optional<Regex::MatchCollection> Matches(const std::string& text) override
 	{
 		std::vector<re2::StringPiece> re2captures(regex.NumberOfCapturingGroups() + 1);
-		bool result = regex.Match(text, 0, text.length(), RE2::ANCHOR_BOTH, &re2captures[0], static_cast<int>(re2captures.size()));
+		bool result = regex.Match(text, 0, text.length(), RE2::ANCHOR_BOTH, re2captures.data(), static_cast<int>(re2captures.size()));
 		if (!result)
 			return std::nullopt;
 
diff --git a/src/modules/extra/m_ssl_gnutls.cpp b/src/modules/extra/m_ssl_gnutls.cpp
index b21ce982f..d1f31817c 100644
--- a/src/modules/extra/m_ssl_gnutls.cpp
+++ b/src/modules/extra/m_ssl_gnutls.cpp
@@ -229,7 +229,7 @@ namespace GnuTLS
 				gnutls_x509_crt_deinit(cert);
 		}
 
-		gnutls_x509_crt_t* raw() { return &certs[0]; }
+		gnutls_x509_crt_t* raw() { return certs.data(); }
 		size_t size() const { return certs.size(); }
 	};
 
@@ -983,15 +983,15 @@ public:
 		unsigned int nameType = GNUTLS_NAME_DNS;
 
 		// First, determine the size of the hostname.
-		if (gnutls_server_name_get(sess, &nameBuffer[0], &nameLength, &nameType, 0) != GNUTLS_E_SHORT_MEMORY_BUFFER)
+		if (gnutls_server_name_get(sess, nameBuffer.data(), &nameLength, &nameType, 0) != GNUTLS_E_SHORT_MEMORY_BUFFER)
 			return false;
 
 		// Then retrieve the hostname.
 		nameBuffer.resize(nameLength);
-		if (gnutls_server_name_get(sess, &nameBuffer[0], &nameLength, &nameType, 0) != GNUTLS_E_SUCCESS)
+		if (gnutls_server_name_get(sess, nameBuffer.data(), &nameLength, &nameType, 0) != GNUTLS_E_SUCCESS)
 			return false;
 
-		out.append(&nameBuffer[0]);
+		out.append(nameBuffer.data());
 		return true;
 	}
 
diff --git a/src/modules/m_abbreviation.cpp b/src/modules/m_abbreviation.cpp
index dfed73020..4517e6a45 100644
--- a/src/modules/m_abbreviation.cpp
+++ b/src/modules/m_abbreviation.cpp
@@ -51,7 +51,8 @@ public:
 
 		/* Look for any command that starts with the same characters, if it does, replace the command string with it */
 		size_t clen = command.length() - 1;
-		std::string foundcommand, matchlist;
+		std::string foundcommand;
+		std::string matchlist;
 		bool foundmatch = false;
 		for (const auto& [cmdname, _] : ServerInstance->Parser.GetCommands())
 		{
diff --git a/src/modules/m_alias.cpp b/src/modules/m_alias.cpp
index 621fa4f04..ea8be2c41 100644
--- a/src/modules/m_alias.cpp
+++ b/src/modules/m_alias.cpp
@@ -119,7 +119,7 @@ public:
 	{
 	}
 
-	std::string GetVar(std::string varname, const std::string &original_line)
+	static std::string GetVar(std::string varname, const std::string &original_line)
 	{
 		irc::spacesepstream ss(original_line);
 		varname.erase(varname.begin());
@@ -144,7 +144,7 @@ public:
 		return word;
 	}
 
-	std::string CreateRFCMessage(const std::string& command, CommandBase::Params& parameters)
+	static std::string CreateRFCMessage(const std::string& command, CommandBase::Params& parameters)
 	{
 		std::string message(command);
 		for (CommandBase::Params::const_iterator iter = parameters.begin(); iter != parameters.end();)
@@ -377,7 +377,8 @@ public:
 
 		irc::tokenstream ss(result);
 		CommandBase::Params pars;
-		std::string command, token;
+		std::string command;
+		std::string token;
 
 		ss.GetMiddle(command);
 		while (ss.GetTrailing(token))
diff --git a/src/modules/m_anticaps.cpp b/src/modules/m_anticaps.cpp
index e9bd3d45e..beb29f2ec 100644
--- a/src/modules/m_anticaps.cpp
+++ b/src/modules/m_anticaps.cpp
@@ -52,7 +52,7 @@ class AntiCapsMode final
 	: public ParamMode<AntiCapsMode, SimpleExtItem<AntiCapsSettings>>
 {
 private:
-	bool ParseMethod(irc::sepstream& stream, AntiCapsMethod& method)
+	static bool ParseMethod(irc::sepstream& stream, AntiCapsMethod& method)
 	{
 		std::string methodstr;
 		if (!stream.GetToken(methodstr))
@@ -74,7 +74,7 @@ private:
 		return true;
 	}
 
-	bool ParseMinimumLength(irc::sepstream& stream, uint16_t& minlen)
+	static bool ParseMinimumLength(irc::sepstream& stream, uint16_t& minlen)
 	{
 		std::string minlenstr;
 		if (!stream.GetToken(minlenstr))
@@ -88,7 +88,7 @@ private:
 		return true;
 	}
 
-	bool ParsePercent(irc::sepstream& stream, uint8_t& percent)
+	static bool ParsePercent(irc::sepstream& stream, uint8_t& percent)
 	{
 		std::string percentstr;
 		if (!stream.GetToken(percentstr))
@@ -176,7 +176,7 @@ private:
 		ServerInstance->Modes.Process(ServerInstance->FakeClient, channel, nullptr, changelist);
 	}
 
-	void InformUser(Channel* channel, User* user, const std::string& message)
+	static void InformUser(Channel* channel, User* user, const std::string& message)
 	{
 		user->WriteNumeric(Numerics::CannotSendTo(channel, message + " and was blocked."));
 	}
diff --git a/src/modules/m_auditorium.cpp b/src/modules/m_auditorium.cpp
index a7b3d0804..566171fe5 100644
--- a/src/modules/m_auditorium.cpp
+++ b/src/modules/m_auditorium.cpp
@@ -118,10 +118,7 @@ public:
 
 		// Can you see the list by permission?
 		ModResult res = CheckExemption::Call(exemptionprov, issuer, memb->chan, "auditorium-see");
-		if (res.check(OpsCanSee && memb->chan->GetPrefixValue(issuer) >= OP_VALUE))
-			return true;
-
-		return false;
+		return res.check(OpsCanSee && memb->chan->GetPrefixValue(issuer) >= OP_VALUE);
 	}
 
 	ModResult OnNamesListItem(LocalUser* issuer, Membership* memb, std::string& prefixes, std::string& nick) override
diff --git a/src/modules/m_autoop.cpp b/src/modules/m_autoop.cpp
index dca983b3e..dc03eddb2 100644
--- a/src/modules/m_autoop.cpp
+++ b/src/modules/m_autoop.cpp
@@ -42,7 +42,7 @@ public:
 		syntax = "<prefix>:<mask>";
 	}
 
-	PrefixMode* FindMode(const std::string& mid)
+	static PrefixMode* FindMode(const std::string& mid)
 	{
 		if (mid.length() == 1)
 			return ServerInstance->Modes.FindPrefixMode(mid[0]);
diff --git a/src/modules/m_banexception.cpp b/src/modules/m_banexception.cpp
index 9234c1b6f..b9bfab626 100644
--- a/src/modules/m_banexception.cpp
+++ b/src/modules/m_banexception.cpp
@@ -89,7 +89,8 @@ public:
 		for (const ListModeBase::ListItem& ban : *list)
 		{
 			bool inverted;
-			std::string name, value;
+			std::string name;
+			std::string value;
 			if (!ExtBan::Parse(ban.mask, name, value, inverted))
 				continue;
 
diff --git a/src/modules/m_bcrypt.cpp b/src/modules/m_bcrypt.cpp
index 0e464081c..62e50db07 100644
--- a/src/modules/m_bcrypt.cpp
+++ b/src/modules/m_bcrypt.cpp
@@ -43,7 +43,7 @@ private:
 public:
 	unsigned long rounds = 10;
 
-	std::string Generate(const std::string& data, const std::string& salt)
+	static std::string Generate(const std::string& data, const std::string& salt)
 	{
 		char hash[64];
 		_crypt_blowfish_rn(data.c_str(), salt.c_str(), hash, sizeof(hash));
diff --git a/src/modules/m_cban.cpp b/src/modules/m_cban.cpp
index e810aed2c..57099b257 100644
--- a/src/modules/m_cban.cpp
+++ b/src/modules/m_cban.cpp
@@ -127,7 +127,7 @@ public:
 				return CmdResult::FAILURE;
 			}
 			const char *reason = (parameters.size() > 2) ? parameters[2].c_str() : "No reason supplied";
-			CBan* r = new CBan(ServerInstance->Time(), duration, user->nick.c_str(), reason, parameters[0].c_str());
+			CBan* r = new CBan(ServerInstance->Time(), duration, user->nick, reason, parameters[0]);
 
 			if (ServerInstance->XLines->AddLine(r, user))
 			{
diff --git a/src/modules/m_check.cpp b/src/modules/m_check.cpp
index ede792d42..ea3243272 100644
--- a/src/modules/m_check.cpp
+++ b/src/modules/m_check.cpp
@@ -41,7 +41,7 @@ private:
 	User* const user;
 	const std::string& target;
 
-	std::string FormatTime(time_t ts)
+	static std::string FormatTime(time_t ts)
 	{
 		std::string timestr(InspIRCd::TimeString(ts, "%Y-%m-%d %H:%M:%S UTC (", true));
 		timestr.append(ConvToStr(ts));
diff --git a/src/modules/m_cloaking.cpp b/src/modules/m_cloaking.cpp
index c8a8cfaa2..c8766478f 100644
--- a/src/modules/m_cloaking.cpp
+++ b/src/modules/m_cloaking.cpp
@@ -241,7 +241,7 @@ public:
 	 * @param domainparts The number of domain labels that should be visible.
 	 * @return The visible segment of the hostname.
 	 */
-	std::string VisibleDomainParts(const std::string& host, unsigned int domainparts)
+	static std::string VisibleDomainParts(const std::string& host, unsigned int domainparts)
 	{
 		// The position at which we found the last dot.
 		std::string::const_reverse_iterator dotpos;
@@ -302,8 +302,11 @@ public:
 	std::string SegmentIP(const CloakInfo& info, const irc::sockets::sockaddrs& ip, bool full)
 	{
 		std::string bindata;
-		size_t hop1, hop2, hop3;
-		size_t len1, len2;
+		size_t hop1;
+		size_t hop2;
+		size_t hop3;
+		size_t len1;
+		size_t len2;
 		std::string rv;
 		if (ip.family() == AF_INET6)
 		{
diff --git a/src/modules/m_codepage.cpp b/src/modules/m_codepage.cpp
index f72907bcf..e6ff7a919 100644
--- a/src/modules/m_codepage.cpp
+++ b/src/modules/m_codepage.cpp
@@ -198,7 +198,7 @@ private:
 		hashmap.swap(newhash);
 	}
 
-	void CheckDuplicateNick()
+	static void CheckDuplicateNick()
 	{
 		insp::flat_set<std::string, irc::insensitive_swo> duplicates;
 		for (auto* user : ServerInstance->Users.GetLocalUsers())
@@ -211,7 +211,7 @@ private:
 		}
 	}
 
-	void CheckInvalidNick()
+	static void CheckInvalidNick()
 	{
 		for (auto* user : ServerInstance->Users.GetLocalUsers())
 		{
diff --git a/src/modules/m_connectban.cpp b/src/modules/m_connectban.cpp
index cf11e299e..535702101 100644
--- a/src/modules/m_connectban.cpp
+++ b/src/modules/m_connectban.cpp
@@ -47,7 +47,7 @@ private:
 	time_t ignoreuntil = 0;
 	std::string banmessage;
 
-	unsigned char GetRange(LocalUser* user)
+	unsigned char GetRange(LocalUser* user) const
 	{
 		int family = user->client_sa.family();
 		switch (family)
diff --git a/src/modules/m_dccallow.cpp b/src/modules/m_dccallow.cpp
index f113215f7..3384741f3 100644
--- a/src/modules/m_dccallow.cpp
+++ b/src/modules/m_dccallow.cpp
@@ -194,6 +194,7 @@ public:
 		: Command(parent, "DCCALLOW", 0)
 		, ext(Ext)
 	{
+		allow_empty_last_param = false;
 		syntax = { "[(+|-)<nick> [<time>]]", "LIST", "HELP" };
 		/* XXX we need to fix this so it can work with translation stuff (i.e. move +- into a seperate param */
 	}
@@ -201,15 +202,15 @@ public:
 	CmdResult Handle(User* user, const Params& parameters) override
 	{
 		/* syntax: DCCALLOW [(+|-)<nick> [<time>]]|[LIST|HELP] */
-		if (!parameters.size())
+		if (parameters.empty())
 		{
 			// display current DCCALLOW list
 			DisplayDCCAllowList(user);
 			return CmdResult::FAILURE;
 		}
-		else if (parameters.size() > 0)
+		else
 		{
-			char action = *parameters[0].c_str();
+			char action = parameters[0][0];
 
 			// if they didn't specify an action, this is probably a command
 			if (action != '+' && action != '-')
@@ -344,7 +345,7 @@ public:
 		return ROUTE_BROADCAST;
 	}
 
-	void DisplayHelp(User* user)
+	static void DisplayHelp(User* user)
 	{
 		user->WriteNumeric(RPL_HELPSTART, "*", "DCCALLOW [(+|-)<nick> [<time>]]|[LIST|HELP]");
 		for (const auto& helpline : helptext)
@@ -436,7 +437,7 @@ public:
 				if (irc::equals(ctcpname, "DCC") && !ctcpbody.empty())
 				{
 					dl = ext.Get(u);
-					if (dl && dl->size())
+					if (dl && !dl->empty())
 					{
 						for (const auto& dccallow : *dl)
 						{
@@ -524,7 +525,7 @@ public:
 			dl = ext.Get(u);
 			if (dl)
 			{
-				if (dl->size())
+				if (!dl->empty())
 				{
 					dccallowlist::iterator iter2 = dl->begin();
 					while (iter2 != dl->end())
@@ -559,7 +560,7 @@ public:
 			dl = ext.Get(u);
 			if (dl)
 			{
-				if (dl->size())
+				if (!dl->empty())
 				{
 					for (dccallowlist::iterator i = dl->begin(); i != dl->end(); ++i)
 					{
@@ -582,7 +583,7 @@ public:
 		}
 	}
 
-	void RemoveFromUserlist(User *user)
+	static void RemoveFromUserlist(User *user)
 	{
 		// remove user from userlist
 		for (userlist::iterator j = ul.begin(); j != ul.end(); ++j)
diff --git a/src/modules/m_disable.cpp b/src/modules/m_disable.cpp
index 774ecb278..57f471d13 100644
--- a/src/modules/m_disable.cpp
+++ b/src/modules/m_disable.cpp
@@ -64,7 +64,7 @@ private:
 		}
 	}
 
-	void WriteLog(const char* message, ...) ATTR_PRINTF(2, 3)
+	void WriteLog(const char* message, ...) const ATTR_PRINTF(2, 3)
 	{
 		std::string buffer;
 		VAFORMAT(buffer, message, message);
@@ -127,7 +127,7 @@ public:
 
 	ModResult OnNumeric(User* user, const Numeric::Numeric& numeric) override
 	{
-		if (numeric.GetNumeric() != RPL_COMMANDS || numeric.GetParams().size() < 1)
+		if (numeric.GetNumeric() != RPL_COMMANDS || numeric.GetParams().empty())
 			return MOD_RES_PASSTHRU; // The numeric isn't the one we care about.
 
 		if (!fakenonexistent || !IS_LOCAL(user))
diff --git a/src/modules/m_dnsbl.cpp b/src/modules/m_dnsbl.cpp
index 5530f0fde..d1e55238f 100644
--- a/src/modules/m_dnsbl.cpp
+++ b/src/modules/m_dnsbl.cpp
@@ -411,11 +411,10 @@ public:
 		std::string reversedip;
 		if (user->client_sa.family() == AF_INET)
 		{
-			unsigned int a, b, c, d;
-			d = (unsigned int) (user->client_sa.in4.sin_addr.s_addr >> 24) & 0xFF;
-			c = (unsigned int) (user->client_sa.in4.sin_addr.s_addr >> 16) & 0xFF;
-			b = (unsigned int) (user->client_sa.in4.sin_addr.s_addr >> 8) & 0xFF;
-			a = (unsigned int) user->client_sa.in4.sin_addr.s_addr & 0xFF;
+			unsigned int a = (unsigned int) user->client_sa.in4.sin_addr.s_addr & 0xFF;
+			unsigned int b = (unsigned int) (user->client_sa.in4.sin_addr.s_addr >> 8) & 0xFF;
+			unsigned int c = (unsigned int) (user->client_sa.in4.sin_addr.s_addr >> 16) & 0xFF;
+			unsigned int d = (unsigned int) (user->client_sa.in4.sin_addr.s_addr >> 24) & 0xFF;
 
 			reversedip = ConvToStr(d) + "." + ConvToStr(c) + "." + ConvToStr(b) + "." + ConvToStr(a);
 		}
diff --git a/src/modules/m_filter.cpp b/src/modules/m_filter.cpp
index 51c13c07a..cb1d6a893 100644
--- a/src/modules/m_filter.cpp
+++ b/src/modules/m_filter.cpp
@@ -229,7 +229,7 @@ public:
 	std::pair<bool, std::string> AddFilter(const std::string& freeform, FilterAction type, const std::string& reason, unsigned long duration, const std::string& flags, bool config = false);
 	void ReadConfig(ConfigStatus& status) override;
 	void GetLinkData(LinkData& data, std::string& compatdata) override;
-	std::string EncodeFilter(const FilterResult& filter);
+	static std::string EncodeFilter(const FilterResult& filter);
 	FilterResult DecodeFilter(const std::string &data);
 	void OnSyncNetwork(ProtocolInterface::Server& server) override;
 	void OnDecodeMetaData(Extensible* target, const std::string &extname, const std::string &extdata) override;
@@ -465,7 +465,7 @@ ModResult ModuleFilter::OnUserPreMessage(User* user, const MessageTarget& msgtar
 		}
 		else if (f->action == FA_SHUN && (ServerInstance->XLines->GetFactory("SHUN")))
 		{
-			Shun* sh = new Shun(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName.c_str(), f->reason.c_str(), user->GetIPString());
+			Shun* sh = new Shun(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, user->GetIPString());
 			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was shunned for %s (expires on %s) because their message to %s matched %s (%s)",
 				user->nick.c_str(), sh->Displayable().c_str(), InspIRCd::DurationString(f->duration).c_str(),
 				InspIRCd::TimeString(ServerInstance->Time() + f->duration).c_str(),
@@ -479,7 +479,7 @@ ModResult ModuleFilter::OnUserPreMessage(User* user, const MessageTarget& msgtar
 		}
 		else if (f->action == FA_GLINE)
 		{
-			GLine* gl = new GLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName.c_str(), f->reason.c_str(), "*", user->GetIPString());
+			GLine* gl = new GLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, "*", user->GetIPString());
 			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was G-lined for %s (expires on %s) because their message to %s matched %s (%s)",
 				user->nick.c_str(), gl->Displayable().c_str(), InspIRCd::DurationString(f->duration).c_str(),
 				InspIRCd::TimeString(ServerInstance->Time() + f->duration).c_str(),
@@ -493,7 +493,7 @@ ModResult ModuleFilter::OnUserPreMessage(User* user, const MessageTarget& msgtar
 		}
 		else if (f->action == FA_ZLINE)
 		{
-			ZLine* zl = new ZLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName.c_str(), f->reason.c_str(), user->GetIPString());
+			ZLine* zl = new ZLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, user->GetIPString());
 			ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was Z-lined for %s (expires on %s) because their message to %s matched %s (%s)",
 				user->nick.c_str(), zl->Displayable().c_str(), InspIRCd::DurationString(f->duration).c_str(),
 				InspIRCd::TimeString(ServerInstance->Time() + f->duration).c_str(),
@@ -522,7 +522,7 @@ ModResult ModuleFilter::OnPreCommand(std::string& command, CommandBase::Params&
 		if (command == "QUIT")
 		{
 			/* QUIT with no reason: nothing to do */
-			if (parameters.size() < 1)
+			if (parameters.empty())
 				return MOD_RES_PASSTHRU;
 
 			parting = false;
@@ -570,7 +570,7 @@ ModResult ModuleFilter::OnPreCommand(std::string& command, CommandBase::Params&
 			if (f->action == FA_GLINE)
 			{
 				/* Note: We G-line *@IP so that if their host doesn't resolve the G-line still applies. */
-				GLine* gl = new GLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName.c_str(), f->reason.c_str(), "*", user->GetIPString());
+				GLine* gl = new GLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, "*", user->GetIPString());
 				ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was G-lined for %s (expires on %s) because their %s message matched %s (%s)",
 					user->nick.c_str(), gl->Displayable().c_str(),
 					InspIRCd::DurationString(f->duration).c_str(),
@@ -586,7 +586,7 @@ ModResult ModuleFilter::OnPreCommand(std::string& command, CommandBase::Params&
 			}
 			if (f->action == FA_ZLINE)
 			{
-				ZLine* zl = new ZLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName.c_str(), f->reason.c_str(), user->GetIPString());
+				ZLine* zl = new ZLine(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, user->GetIPString());
 				ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was Z-lined for %s (expires on %s) because their %s message matched %s (%s)",
 					user->nick.c_str(), zl->Displayable().c_str(),
 					InspIRCd::DurationString(f->duration).c_str(),
@@ -603,7 +603,7 @@ ModResult ModuleFilter::OnPreCommand(std::string& command, CommandBase::Params&
 			else if (f->action == FA_SHUN && (ServerInstance->XLines->GetFactory("SHUN")))
 			{
 				/* Note: We shun *!*@IP so that if their host doesnt resolve the shun still applies. */
-				Shun* sh = new Shun(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName.c_str(), f->reason.c_str(), user->GetIPString());
+				Shun* sh = new Shun(ServerInstance->Time(), f->duration, ServerInstance->Config->ServerName, f->reason, user->GetIPString());
 				ServerInstance->SNO.WriteGlobalSno('f', InspIRCd::Format("%s (%s) was shunned for %s (expires on %s) because their %s message matched %s (%s)",
 					user->nick.c_str(), sh->Displayable().c_str(),
 					InspIRCd::DurationString(f->duration).c_str(),
diff --git a/src/modules/m_globalload.cpp b/src/modules/m_globalload.cpp
index 6e9a0f861..e1f5e7292 100644
--- a/src/modules/m_globalload.cpp
+++ b/src/modules/m_globalload.cpp
@@ -42,9 +42,9 @@ public:
 	{
 		std::string servername = parameters.size() > 1 ? parameters[1] : "*";
 
-		if (InspIRCd::Match(ServerInstance->Config->ServerName.c_str(), servername))
+		if (InspIRCd::Match(ServerInstance->Config->ServerName, servername))
 		{
-			if (ServerInstance->Modules.Load(parameters[0].c_str()))
+			if (ServerInstance->Modules.Load(parameters[0]))
 			{
 				ServerInstance->SNO.WriteToSnoMask('a', "NEW MODULE '%s' GLOBALLY LOADED BY '%s'",parameters[0].c_str(), user->nick.c_str());
 				user->WriteRemoteNumeric(RPL_LOADEDMODULE, parameters[0], "Module successfully loaded.");
@@ -88,7 +88,7 @@ public:
 
 		std::string servername = parameters.size() > 1 ? parameters[1] : "*";
 
-		if (InspIRCd::Match(ServerInstance->Config->ServerName.c_str(), servername))
+		if (InspIRCd::Match(ServerInstance->Config->ServerName, servername))
 		{
 			Module* m = ServerInstance->Modules.Find(parameters[0]);
 			if (m)
@@ -134,7 +134,7 @@ public:
 	{
 		std::string servername = parameters.size() > 1 ? parameters[1] : "*";
 
-		if (InspIRCd::Match(ServerInstance->Config->ServerName.c_str(), servername))
+		if (InspIRCd::Match(ServerInstance->Config->ServerName, servername))
 		{
 			Module* m = ServerInstance->Modules.Find(parameters[0]);
 			if (m)
diff --git a/src/modules/m_ident.cpp b/src/modules/m_ident.cpp
index 17b5c4c24..b923e6371 100644
--- a/src/modules/m_ident.cpp
+++ b/src/modules/m_ident.cpp
@@ -192,7 +192,7 @@ public:
 		}
 	}
 
-	bool HasResult()
+	bool HasResult() const
 	{
 		return done;
 	}
diff --git a/src/modules/m_ircv3_capnotify.cpp b/src/modules/m_ircv3_capnotify.cpp
index 9a06189fa..0706ba88b 100644
--- a/src/modules/m_ircv3_capnotify.cpp
+++ b/src/modules/m_ircv3_capnotify.cpp
@@ -28,9 +28,7 @@ class CapNotify final
 	bool OnRequest(LocalUser* user, bool add) override
 	{
 		// Users using the negotiation protocol v3.2 or newer may not turn off cap-notify
-		if ((!add) && (GetProtocol(user) != Cap::CAP_LEGACY))
-			return false;
-		return true;
+		return add || GetProtocol(user) == Cap::CAP_LEGACY;
 	}
 
 	bool OnList(LocalUser* user) override
diff --git a/src/modules/m_ircv3_sts.cpp b/src/modules/m_ircv3_sts.cpp
index d2823f895..2f5287248 100644
--- a/src/modules/m_ircv3_sts.cpp
+++ b/src/modules/m_ircv3_sts.cpp
@@ -132,7 +132,7 @@ private:
 	STSCap cap;
 
 	// The IRCv3 STS specification requires that the server is listening using TLS using a valid certificate.
-	bool HasValidSSLPort(unsigned int port)
+	static bool HasValidSSLPort(unsigned int port)
 	{
 		for (const auto& ls : ServerInstance->ports)
 		{
diff --git a/src/modules/m_joinflood.cpp b/src/modules/m_joinflood.cpp
index f7e4aaa1d..4aca441e1 100644
--- a/src/modules/m_joinflood.cpp
+++ b/src/modules/m_joinflood.cpp
@@ -59,7 +59,7 @@ public:
 			counter++;
 	}
 
-	bool shouldlock()
+	bool shouldlock() const
 	{
 		return (counter >= this->joins);
 	}
diff --git a/src/modules/m_log_sql.cpp b/src/modules/m_log_sql.cpp
index 4ffe6784a..7e02d43f9 100644
--- a/src/modules/m_log_sql.cpp
+++ b/src/modules/m_log_sql.cpp
@@ -87,7 +87,6 @@ public:
 	{
 	}
 
-public:
 	Log::MethodPtr Create(std::shared_ptr<ConfigTag> tag) override
 	{
 		dynamic_reference<SQL::Provider> sql(creator, "SQL");
diff --git a/src/modules/m_md5.cpp b/src/modules/m_md5.cpp
index 7386041c4..8a1c9eb3b 100644
--- a/src/modules/m_md5.cpp
+++ b/src/modules/m_md5.cpp
@@ -43,8 +43,8 @@ public:
 		MD5_Update(&context, reinterpret_cast<const unsigned char*>(data.data()), data.length());
 
 		std::vector<unsigned char> bytes(16);
-		MD5_Final(&bytes[0], &context);
-		return std::string(reinterpret_cast<const char*>(&bytes[0]), bytes.size());
+		MD5_Final(bytes.data(), &context);
+		return std::string(reinterpret_cast<const char*>(bytes.data()), bytes.size());
 	}
 
 	MD5Provider(Module* parent)
diff --git a/src/modules/m_nickflood.cpp b/src/modules/m_nickflood.cpp
index e2970e073..9e13975d1 100644
--- a/src/modules/m_nickflood.cpp
+++ b/src/modules/m_nickflood.cpp
@@ -58,7 +58,7 @@ public:
 			counter++;
 	}
 
-	bool shouldlock()
+	bool shouldlock() const
 	{
 		return ((ServerInstance->Time() <= reset) && (counter == this->nicks));
 	}
diff --git a/src/modules/m_override.cpp b/src/modules/m_override.cpp
index 72fa45817..fa9ae2fe5 100644
--- a/src/modules/m_override.cpp
+++ b/src/modules/m_override.cpp
@@ -109,7 +109,7 @@ private:
 		return false;
 	}
 
-	ModResult HandleJoinOverride(LocalUser* user, Channel* chan, const std::string& keygiven, const char* bypasswhat, const char* mode)
+	ModResult HandleJoinOverride(LocalUser* user, Channel* chan, const std::string& keygiven, const char* bypasswhat, const char* mode) const
 	{
 		if (RequireKey && keygiven != "override")
 		{
diff --git a/src/modules/m_pbkdf2.cpp b/src/modules/m_pbkdf2.cpp
index 3811ccff8..259f326ad 100644
--- a/src/modules/m_pbkdf2.cpp
+++ b/src/modules/m_pbkdf2.cpp
@@ -66,11 +66,9 @@ public:
 		return ConvToStr(this->iterations) + ":" + Base64::Encode(this->hash) + ":" + Base64::Encode(this->salt);
 	}
 
-	bool IsValid()
+	bool IsValid() const
 	{
-		if (!this->iterations || !this->length || this->salt.empty() || this->hash.empty())
-			return false;
-		return true;
+		return this->iterations && this->length && !this->salt.empty() && !this->hash.empty();
 	}
 };
 
@@ -82,7 +80,7 @@ public:
 	unsigned long iterations;
 	size_t dkey_length;
 
-	std::string PBKDF2(const std::string& pass, const std::string& salt, unsigned long itr = 0, size_t dkl = 0)
+	std::string PBKDF2(const std::string& pass, const std::string& salt, unsigned long itr = 0, size_t dkl = 0) const
 	{
 		size_t blocks = std::ceil((double)dkl / provider->out_size);
 
diff --git a/src/modules/m_repeat.cpp b/src/modules/m_repeat.cpp
index 9120cde9a..33bcf731a 100644
--- a/src/modules/m_repeat.cpp
+++ b/src/modules/m_repeat.cpp
@@ -262,7 +262,7 @@ public:
 	}
 
 private:
-	bool ParseSettings(User* source, std::string& parameter, ChannelSettings& settings)
+	static bool ParseSettings(User* source, std::string& parameter, ChannelSettings& settings)
 	{
 		irc::sepstream stream(parameter, ':');
 		std::string	item;
diff --git a/src/modules/m_restrictmsg.cpp b/src/modules/m_restrictmsg.cpp
index 073ab6a80..acbff05ae 100644
--- a/src/modules/m_restrictmsg.cpp
+++ b/src/modules/m_restrictmsg.cpp
@@ -32,7 +32,7 @@ class ModuleRestrictMsg final
 	, public CTCTags::EventListener
 {
 private:
-	ModResult HandleMessage(User* user, const MessageTarget& target)
+	static ModResult HandleMessage(User* user, const MessageTarget& target)
 	{
 		if ((target.type == MessageTarget::TYPE_USER) && (IS_LOCAL(user)))
 		{
diff --git a/src/modules/m_rline.cpp b/src/modules/m_rline.cpp
index daf59ff7e..0d1d01f91 100644
--- a/src/modules/m_rline.cpp
+++ b/src/modules/m_rline.cpp
@@ -68,7 +68,7 @@ public:
 	{
 		if (ZlineOnMatch)
 		{
-			ZLine* zl = new ZLine(ServerInstance->Time(), duration ? expiry - ServerInstance->Time() : 0, MODNAME "@" + ServerInstance->Config->ServerName, reason.c_str(), u->GetIPString());
+			ZLine* zl = new ZLine(ServerInstance->Time(), duration ? expiry - ServerInstance->Time() : 0, MODNAME "@" + ServerInstance->Config->ServerName, reason, u->GetIPString());
 			if (ServerInstance->XLines->AddLine(zl, nullptr))
 			{
 				if (!duration)
@@ -161,7 +161,7 @@ public:
 
 			try
 			{
-				r = factory.Generate(ServerInstance->Time(), duration, user->nick.c_str(), parameters[2].c_str(), parameters[0].c_str());
+				r = factory.Generate(ServerInstance->Time(), duration, user->nick, parameters[2], parameters[0]);
 			}
 			catch (const ModuleException& e)
 			{
diff --git a/src/modules/m_sasl.cpp b/src/modules/m_sasl.cpp
index 7bca715db..48cd996f2 100644
--- a/src/modules/m_sasl.cpp
+++ b/src/modules/m_sasl.cpp
@@ -210,7 +210,7 @@ public:
 		SendSASL(user, "*", 'S', params);
 	}
 
-	SaslResult GetSaslResult(const std::string &result_)
+	static SaslResult GetSaslResult(const std::string &result_)
 	{
 		if (result_ == "F")
 			return SASL_FAIL;
@@ -351,7 +351,7 @@ public:
 			SaslAuthenticator *sasl = authExt.Get(user);
 			if (!sasl)
 				authExt.SetFwd(user, user, parameters[0], sslapi);
-			else if (sasl->SendClientMessage(parameters) == false)	// IAL abort extension --nenolod
+			else if (!sasl->SendClientMessage(parameters))
 			{
 				sasl->AnnounceState();
 				authExt.Unset(user);
diff --git a/src/modules/m_sha2.cpp b/src/modules/m_sha2.cpp
index 7d85d5a8e..44f92c17c 100644
--- a/src/modules/m_sha2.cpp
+++ b/src/modules/m_sha2.cpp
@@ -52,8 +52,8 @@ public:
 	std::string GenerateRaw(const std::string& data) override
 	{
 		std::vector<char> bytes(out_size);
-		SHA(reinterpret_cast<const unsigned char*>(data.data()), static_cast<unsigned int>(data.size()), reinterpret_cast<unsigned char*>(&bytes[0]));
-		return std::string(&bytes[0], bytes.size());
+		SHA(reinterpret_cast<const unsigned char*>(data.data()), static_cast<unsigned int>(data.size()), reinterpret_cast<unsigned char*>(bytes.data()));
+		return std::string(bytes.data(), bytes.size());
 	}
 };
 
diff --git a/src/modules/m_showwhois.cpp b/src/modules/m_showwhois.cpp
index 56147c5a4..7656e2c3c 100644
--- a/src/modules/m_showwhois.cpp
+++ b/src/modules/m_showwhois.cpp
@@ -52,7 +52,7 @@ public:
 		access_needed = CmdAccess::SERVER;
 	}
 
-	void HandleFast(User* dest, User* src)
+	static void HandleFast(User* dest, User* src)
 	{
 		dest->WriteNotice("*** " + src->nick + " (" + src->ident + "@" +
 			src->GetHost(dest->HasPrivPermission("users/auspex")) +
diff --git a/src/modules/m_shun.cpp b/src/modules/m_shun.cpp
index e28043da6..07a3119dc 100644
--- a/src/modules/m_shun.cpp
+++ b/src/modules/m_shun.cpp
@@ -113,7 +113,7 @@ public:
 				expr = parameters[1];
 			}
 
-			Shun* r = new Shun(ServerInstance->Time(), duration, user->nick.c_str(), expr.c_str(), target.c_str());
+			Shun* r = new Shun(ServerInstance->Time(), duration, user->nick, expr, target);
 			if (ServerInstance->XLines->AddLine(r, user))
 			{
 				if (!duration)
@@ -152,7 +152,7 @@ private:
 	TokenList enabledcommands;
 	bool notifyuser;
 
-	bool IsShunned(LocalUser* user)
+	bool IsShunned(LocalUser* user) const
 	{
 		// Exempt the user if they are not fully connected and allowconnect is enabled.
 		if (allowconnect && user->registered != REG_ALL)
diff --git a/src/modules/m_spanningtree/capab.cpp b/src/modules/m_spanningtree/capab.cpp
index bd9e3138d..08533f5a8 100644
--- a/src/modules/m_spanningtree/capab.cpp
+++ b/src/modules/m_spanningtree/capab.cpp
@@ -201,7 +201,9 @@ namespace
 			return true;
 
 		bool okay;
-		std::ostringstream diffconfig, localmissing, remotemissing;
+		std::ostringstream diffconfig;
+		std::ostringstream localmissing;
+		std::ostringstream remotemissing;
 		if (protocol <= PROTO_INSPIRCD_3)
 			okay = CompareModulesOld(property, *remote, diffconfig, localmissing, remotemissing);
 		else
@@ -418,7 +420,7 @@ void TreeSocket::ListDifference(const std::string &one, const std::string &two,
 
 bool TreeSocket::Capab(const CommandBase::Params& params)
 {
-	if (params.size() < 1)
+	if (params.empty())
 	{
 		this->SendError("Invalid number of parameters for CAPAB - Mismatched version");
 		return false;
@@ -471,7 +473,8 @@ bool TreeSocket::Capab(const CommandBase::Params& params)
 		{
 			if (capab->ChanModes != BuildModeList(MODETYPE_CHANNEL))
 			{
-				std::string diffIneed, diffUneed;
+				std::string diffIneed;
+				std::string diffUneed;
 				ListDifference(capab->ChanModes, BuildModeList(MODETYPE_CHANNEL), ' ', diffIneed, diffUneed);
 				if (diffIneed.length() || diffUneed.length())
 				{
@@ -489,7 +492,8 @@ bool TreeSocket::Capab(const CommandBase::Params& params)
 		{
 			if (capab->UserModes != BuildModeList(MODETYPE_USER))
 			{
-				std::string diffIneed, diffUneed;
+				std::string diffIneed;
+				std::string diffUneed;
 				ListDifference(capab->UserModes, BuildModeList(MODETYPE_USER), ' ', diffIneed, diffUneed);
 				if (diffIneed.length() || diffUneed.length())
 				{
diff --git a/src/modules/m_spanningtree/commands.h b/src/modules/m_spanningtree/commands.h
index cf3e1590d..8e8e31f94 100644
--- a/src/modules/m_spanningtree/commands.h
+++ b/src/modules/m_spanningtree/commands.h
@@ -161,7 +161,7 @@ class CommandFJoin final
 	 * @param newname The new name of the channel; must be the same or a case change of the current name
 	 */
 	static void LowerTS(Channel* chan, time_t TS, const std::string& newname);
-	void ProcessModeUUIDPair(const std::string& item, TreeServer* sourceserver, Channel* chan, Modes::ChangeList* modechangelist, FwdFJoinBuilder& fwdfjoin);
+	static void ProcessModeUUIDPair(const std::string& item, TreeServer* sourceserver, Channel* chan, Modes::ChangeList* modechangelist, FwdFJoinBuilder& fwdfjoin);
 public:
 	CommandFJoin(Module* Creator) : ServerCommand(Creator, "FJOIN", 3) { }
 	CmdResult Handle(User* user, Params& params) override;
diff --git a/src/modules/m_spanningtree/compat.cpp b/src/modules/m_spanningtree/compat.cpp
index 7e3c6fcd5..3e0e654f6 100644
--- a/src/modules/m_spanningtree/compat.cpp
+++ b/src/modules/m_spanningtree/compat.cpp
@@ -60,5 +60,4 @@ void TreeSocket::WriteLine(const std::string& original_line)
 	}
 
 	WriteLineInternal(line);
-	return;
 }
diff --git a/src/modules/m_spanningtree/main.h b/src/modules/m_spanningtree/main.h
index abbb21efd..4b14352b9 100644
--- a/src/modules/m_spanningtree/main.h
+++ b/src/modules/m_spanningtree/main.h
@@ -146,11 +146,11 @@ public:
 
 	/** Handle SQUIT
 	 */
-	ModResult HandleSquit(const CommandBase::Params& parameters, User* user);
+	static ModResult HandleSquit(const CommandBase::Params& parameters, User* user);
 
 	/** Handle remote WHOIS
 	 */
-	ModResult HandleRemoteWhois(const CommandBase::Params& parameters, User* user);
+	static ModResult HandleRemoteWhois(const CommandBase::Params& parameters, User* user);
 
 	/** Connect a server locally
 	 */
@@ -166,11 +166,11 @@ public:
 
 	/** Check if any connecting servers should timeout
 	 */
-	void DoConnectTimeout(time_t curtime);
+	static void DoConnectTimeout(time_t curtime);
 
 	/** Handle remote VERSION
 	 */
-	ModResult HandleVersion(const CommandBase::Params& parameters, User* user);
+	static ModResult HandleVersion(const CommandBase::Params& parameters, User* user);
 
 	/** Handle CONNECT
 	 */
diff --git a/src/modules/m_spanningtree/override_map.cpp b/src/modules/m_spanningtree/override_map.cpp
index b686b4c69..0abd3634c 100644
--- a/src/modules/m_spanningtree/override_map.cpp
+++ b/src/modules/m_spanningtree/override_map.cpp
@@ -179,7 +179,7 @@ static std::vector<std::string> GetMap(User* user, TreeServer* current, size_t m
 
 CmdResult CommandMap::Handle(User* user, const Params& parameters)
 {
-	if (parameters.size() > 0)
+	if (!parameters.empty())
 	{
 		// Remote MAP, the target server is the 1st parameter
 		TreeServer* s = Utils->FindServerMask(parameters[0]);
diff --git a/src/modules/m_spanningtree/ping.cpp b/src/modules/m_spanningtree/ping.cpp
index 0ed22845e..452cfde64 100644
--- a/src/modules/m_spanningtree/ping.cpp
+++ b/src/modules/m_spanningtree/ping.cpp
@@ -27,7 +27,6 @@
 #include "utils.h"
 #include "treeserver.h"
 #include "commands.h"
-#include "utils.h"
 
 CmdResult CommandPing::Handle(User* user, Params& params)
 {
diff --git a/src/modules/m_spanningtree/pong.cpp b/src/modules/m_spanningtree/pong.cpp
index 342ca9a7a..fca5e3d85 100644
--- a/src/modules/m_spanningtree/pong.cpp
+++ b/src/modules/m_spanningtree/pong.cpp
@@ -27,7 +27,6 @@
 #include "utils.h"
 #include "treeserver.h"
 #include "commands.h"
-#include "utils.h"
 
 CmdResult CommandPong::HandleServer(TreeServer* server, CommandBase::Params& params)
 {
diff --git a/src/modules/m_spanningtree/precommand.cpp b/src/modules/m_spanningtree/precommand.cpp
index a37d0d52a..b9f745deb 100644
--- a/src/modules/m_spanningtree/precommand.cpp
+++ b/src/modules/m_spanningtree/precommand.cpp
@@ -52,7 +52,7 @@ ModResult ModuleSpanningTree::OnPreCommand(std::string &command, CommandBase::Pa
 			return this->HandleRemoteWhois(parameters,user);
 		}
 	}
-	else if ((command == "VERSION") && (parameters.size() > 0))
+	else if ((command == "VERSION") && (!parameters.empty()))
 	{
 		return this->HandleVersion(parameters,user);
 	}
diff --git a/src/modules/m_spanningtree/server.cpp b/src/modules/m_spanningtree/server.cpp
index 535299e72..cddcd03b4 100644
--- a/src/modules/m_spanningtree/server.cpp
+++ b/src/modules/m_spanningtree/server.cpp
@@ -111,7 +111,7 @@ std::shared_ptr<Link> TreeSocket::AuthRemote(const CommandBase::Params& params)
 
 	this->SendCapabilities(2);
 
-	if (!ServerInstance->IsSID(sid))
+	if (!InspIRCd::IsSID(sid))
 	{
 		this->SendError("Invalid format server ID: "+sid+"!");
 		return nullptr;
diff --git a/src/modules/m_spanningtree/treesocket.h b/src/modules/m_spanningtree/treesocket.h
index 85e5de440..914123bf5 100644
--- a/src/modules/m_spanningtree/treesocket.h
+++ b/src/modules/m_spanningtree/treesocket.h
@@ -232,7 +232,7 @@ public:
 	/** Construct a password, optionally hashed with the other side's
 	 * challenge string
 	 */
-	std::string MakePass(const std::string &password, const std::string &challenge);
+	static std::string MakePass(const std::string &password, const std::string &challenge);
 
 	/** When an outbound connection finishes connecting, we receive
 	 * this event, and must send our SERVER string to the other
@@ -260,20 +260,20 @@ public:
 	/** Returns mode list as a string, filtered by type.
 	 * @param type The type of modes to return.
 	 */
-	std::string BuildModeList(ModeType type);
+	static std::string BuildModeList(ModeType type);
 
 	/** If the extban manager exists then build an extban list.
 	 * @param out The buffer to put the extban list in.
 	 * @return True if the extban manager exists; otherwise, false.
 	 */
-	bool BuildExtBanList(std::string& out);
+	static bool BuildExtBanList(std::string& out);
 
 	/** Send my capabilities to the remote side
 	 */
 	void SendCapabilities(int phase);
 
 	/* Isolate and return the elements that are different between two lists */
-	void ListDifference(const std::string &one, const std::string &two, char sep,
+	static void ListDifference(const std::string &one, const std::string &two, char sep,
 		std::string& mleft, std::string& mright);
 
 	bool Capab(const CommandBase::Params& params);
@@ -326,7 +326,7 @@ public:
 	void ProcessLine(std::string &line);
 
 	/** Process message tags received from a remote server. */
-	void ProcessTag(User* source, const std::string& tag, ClientProtocol::TagMap& tags);
+	static void ProcessTag(User* source, const std::string& tag, ClientProtocol::TagMap& tags);
 
 	/** Process a message for a fully connected server. */
 	void ProcessConnectedLine(std::string& tags, std::string& prefix, std::string& command, CommandBase::Params& params);
diff --git a/src/modules/m_spanningtree/treesocket2.cpp b/src/modules/m_spanningtree/treesocket2.cpp
index 602c0dde4..cacccf544 100644
--- a/src/modules/m_spanningtree/treesocket2.cpp
+++ b/src/modules/m_spanningtree/treesocket2.cpp
@@ -37,7 +37,7 @@
 /* Handle ERROR command */
 void TreeSocket::Error(CommandBase::Params& params)
 {
-	std::string msg = params.size() ? params[0] : "";
+	const std::string msg = params.empty() ? "" : params[0];
 	SetError("received ERROR " + msg);
 }
 
diff --git a/src/modules/m_spanningtree/utils.cpp b/src/modules/m_spanningtree/utils.cpp
index 1d90053b1..616b7c199 100644
--- a/src/modules/m_spanningtree/utils.cpp
+++ b/src/modules/m_spanningtree/utils.cpp
@@ -135,7 +135,7 @@ SpanningTreeUtilities::~SpanningTreeUtilities()
 }
 
 // Returns a list of DIRECT servers for a specific channel
-void SpanningTreeUtilities::GetListOfServersForChannel(Channel* c, TreeSocketSet& list, char status, const CUList& exempt_list)
+void SpanningTreeUtilities::GetListOfServersForChannel(Channel* c, TreeSocketSet& list, char status, const CUList& exempt_list) const
 {
 	ModeHandler::Rank minrank = 0;
 	if (status)
@@ -175,7 +175,7 @@ void SpanningTreeUtilities::GetListOfServersForChannel(Channel* c, TreeSocketSet
 	}
 }
 
-void SpanningTreeUtilities::DoOneToAllButSender(const CmdBuilder& params, TreeServer* omitroute)
+void SpanningTreeUtilities::DoOneToAllButSender(const CmdBuilder& params, TreeServer* omitroute) const
 {
 	const std::string& FullLine = params.str();
 
diff --git a/src/modules/m_spanningtree/utils.h b/src/modules/m_spanningtree/utils.h
index 074c1c993..dcf5b73c2 100644
--- a/src/modules/m_spanningtree/utils.h
+++ b/src/modules/m_spanningtree/utils.h
@@ -127,11 +127,11 @@ public:
 
 	/** Send a message from this server to one other local or remote
 	 */
-	void DoOneToOne(const CmdBuilder& params, Server* target);
+	static void DoOneToOne(const CmdBuilder& params, Server* target);
 
 	/** Send a message from this server to all but one other, local or remote
 	 */
-	void DoOneToAllButSender(const CmdBuilder& params, TreeServer* omit);
+	void DoOneToAllButSender(const CmdBuilder& params, TreeServer* omit) const;
 
 	/** Read the spanningtree module's tags from the config file
 	 */
@@ -139,11 +139,11 @@ public:
 
 	/** Handle nick collision
 	 */
-	bool DoCollision(User* u, TreeServer* server, time_t remotets, const std::string& remoteident, const std::string& remoteip, const std::string& remoteuid, const char* collidecmd);
+	static bool DoCollision(User* u, TreeServer* server, time_t remotets, const std::string& remoteident, const std::string& remoteip, const std::string& remoteuid, const char* collidecmd);
 
 	/** Compile a list of servers which contain members of channel c
 	 */
-	void GetListOfServersForChannel(Channel* c, TreeSocketSet& list, char status, const CUList& exempt_list);
+	void GetListOfServersForChannel(Channel* c, TreeSocketSet& list, char status, const CUList& exempt_list) const;
 
 	/** Find a server by name or SID
 	 */
@@ -175,9 +175,9 @@ public:
 	void SendChannelMessage(User* source, Channel* target, const std::string& text, char status, const ClientProtocol::TagMap& tags, const CUList& exempt_list, const char* message_type, TreeSocket* omit = nullptr);
 
 	// Builds link data to be sent to another server.
-	std::string BuildLinkString(uint16_t protocol, Module* mod);
+	static std::string BuildLinkString(uint16_t protocol, Module* mod);
 
 	/** Send the channel list mode limits to either the specified server or all servers if nullptr. */
-	void SendListLimits(Channel* chan, TreeSocket* sock = nullptr);
+	static void SendListLimits(Channel* chan, TreeSocket* sock = nullptr);
 };
 
diff --git a/src/modules/m_sslinfo.cpp b/src/modules/m_sslinfo.cpp
index 7a4601289..511efe21f 100644
--- a/src/modules/m_sslinfo.cpp
+++ b/src/modules/m_sslinfo.cpp
@@ -278,7 +278,7 @@ private:
 	CommandSSLInfo cmd;
 	std::string hash;
 
-	bool MatchFP(ssl_cert* const cert, const std::string& fp) const
+	static bool MatchFP(ssl_cert* const cert, const std::string& fp)
 	{
 		return irc::spacesepstream(fp).Contains(cert->GetFingerprint());
 	}
diff --git a/src/modules/m_svshold.cpp b/src/modules/m_svshold.cpp
index 469130fcb..287c83563 100644
--- a/src/modules/m_svshold.cpp
+++ b/src/modules/m_svshold.cpp
@@ -51,9 +51,7 @@ public:
 
 	bool Matches(User* u) override
 	{
-		if (u->nick == nickname)
-			return true;
-		return false;
+		return u->nick == nickname;
 	}
 
 	bool Matches(const std::string& s) override
@@ -138,7 +136,7 @@ public:
 				user->WriteNotice("*** Invalid duration for SVSHOLD.");
 				return CmdResult::FAILURE;
 			}
-			SVSHold* r = new SVSHold(ServerInstance->Time(), duration, user->nick.c_str(), parameters[2].c_str(), parameters[0].c_str());
+			SVSHold* r = new SVSHold(ServerInstance->Time(), duration, user->nick, parameters[2], parameters[0]);
 
 			if (ServerInstance->XLines->AddLine(r, user))
 			{