refactor: replace call to the size()/length() with empty()

Signed-off-by: Leonard Ossa <leonard.ossa@openvpn.com>

Author: leoossa

openvpn/client/cliemuexr.hpp

@@ -47,7 +47,7 @@ class EmulateExcludeRouteImpl : public EmulateExcludeRoute
 
     bool enabled(const IPVerFlags &ipv) const override
     {
-        return exclude.size() && (ipv.rgv4() || ipv.rgv6());
+        return !exclude.empty() && (ipv.rgv4() || ipv.rgv6());
     }
 
     void emulate(TunBuilderBase *tb, IPVerFlags &ipv, const IP::Addr &server_addr) const override

openvpn/client/clihalt.hpp

@@ -101,12 +101,12 @@ class ClientHalt
 
     static bool is_halt(const StringList &sl)
     {
-        return sl.size() >= 1 && sl[0] == "HALT";
+        return !sl.empty() && sl[0] == "HALT";
     }
 
     static bool is_restart(const StringList &sl)
     {
-        return sl.size() >= 1 && sl[0] == "RESTART";
+        return !sl.empty() && sl[0] == "RESTART";
     }
 
     bool restart_ = false;

openvpn/client/cliopthelper.hpp

@@ -147,7 +147,7 @@ class ParseClientConfig
             // userlocked username/password via <auth-user-pass>
             std::vector<std::string> user_pass;
             const bool auth_user_pass = parse_auth_user_pass(options, &user_pass);
-            if (auth_user_pass && user_pass.size() >= 1)
+            if (auth_user_pass && !user_pass.empty())
             {
                 userlockedUsername_ = user_pass[0];
                 if (user_pass.size() >= 2)
@@ -569,7 +569,7 @@ class ParseClientConfig
             print_pem(os, "cert", sslConfig->extract_cert());
 
             std::vector<std::string> extra_certs = sslConfig->extract_extra_certs();
-            if (extra_certs.size() > 0)
+            if (!extra_certs.empty())
             {
                 os << "<extra-certs>" << std::endl;
                 for (auto &cert : extra_certs)

openvpn/client/cliproto.hpp

@@ -376,7 +376,7 @@ class Session : ProtoContextCallbackInterface,
             {
                 // data packet
                 proto_context.data_decrypt(pt, buf);
-                if (buf.size())
+                if (!buf.empty())
                 {
 #ifdef OPENVPN_PACKET_LOG
                     log_packet(buf, false);
@@ -454,7 +454,7 @@ class Session : ProtoContextCallbackInterface,
             }
 
             // encrypt packet
-            if (buf.size())
+            if (!buf.empty())
             {
                 const ProtoContext::ProtoConfig &c = proto_context.conf();
 
@@ -479,7 +479,7 @@ class Session : ProtoContextCallbackInterface,
                 else
                 {
                     proto_context.data_encrypt(buf);
-                    if (buf.size())
+                    if (!buf.empty())
                     {
                         // send packet via transport to destination
                         OPENVPN_LOG_CLIPROTO("Transport SEND " << server_endpoint_render() << ' ' << proto_context.dump_packet(buf));
@@ -815,7 +815,7 @@ class Session : ProtoContextCallbackInterface,
                 key_words = msg.substr(strlen("AUTH_PENDING,"));
                 auto opts = OptionList::parse_from_csv_static(key_words, nullptr);
                 std::string timeout_str = opts.get_optional("timeout", 1, 20);
-                if (timeout_str != "")
+                if (!timeout_str.empty())
                 {
                     try
                     {

openvpn/client/dns.hpp

@@ -266,7 +266,7 @@ struct DnsOptionsParser : public DnsOptions
             search_domains.insert(search_domains.begin(), DnsDomain(std::move(adapter_domain_suffix)));
         }
 
-        if (!ignore_values && servers.size() && servers[0].addresses.empty())
+        if (!ignore_values && !servers.empty() && servers[0].addresses.empty())
         {
             parse_errors += "\n";
             parse_errors += "dns server does not have an address assigned";

openvpn/client/optfilt.hpp

@@ -144,10 +144,10 @@ class PushedOptionsFilter : public OptionList::FilterBase
     FilterAction route_nopull_filter_(const Option &opt)
     {
         FilterAction action = Accept;
-        if (opt.size() >= 1)
+        if (!opt.empty())
         {
             const std::string &directive = opt.ref(0);
-            if (directive.length() >= 1)
+            if (!directive.empty())
             {
                 switch (directive[0])
                 {

openvpn/client/remotelist.hpp

@@ -131,7 +131,7 @@ class RemoteList : public RC<thread_unsafe_refcount>
 
         bool res_addr_list_defined() const
         {
-            return res_addr_list && res_addr_list->size() > 0;
+            return res_addr_list && !res_addr_list->empty();
         }
 
         std::string actual_host() const
@@ -231,7 +231,7 @@ class RemoteList : public RC<thread_unsafe_refcount>
     struct Directives
     {
         explicit Directives(const std::string &conn_tag = "")
-            : connection(conn_tag.length() ? conn_tag : "connection")
+            : connection(!conn_tag.empty() ? conn_tag : "connection")
         {
         }
 
@@ -685,7 +685,7 @@ class RemoteList : public RC<thread_unsafe_refcount>
     // return true if object has at least one connection entry
     bool defined() const
     {
-        return list.size() > 0;
+        return !list.empty();
     }
 
     // return remote list size

openvpn/common/hostport.hpp

@@ -63,7 +63,7 @@ inline bool is_valid_host_char(const char c)
 
 inline bool is_valid_host(const std::string &host)
 {
-    if (!host.length() || host.length() > 256)
+    if (host.empty() || host.length() > 256)
         return false;
     for (const auto &c : host)
     {
@@ -80,7 +80,7 @@ inline bool is_valid_unix_sock_char(const unsigned char c)
 
 inline bool is_valid_unix_sock(const std::string &host)
 {
-    if (!host.length() || host.length() > 256)
+    if (host.empty() || host.length() > 256)
         return false;
     for (const auto &c : host)
     {

openvpn/common/options.hpp

@@ -173,7 +173,7 @@ class Option
     {
         try
         {
-            if (data.size() > 0)
+            if (!data.empty())
                 return Unicode::utf8_printable(data[0], 32);
             else
                 return "";
@@ -425,7 +425,7 @@ class Option
     std::string err_ref() const
     {
         std::string ret = "option";
-        if (data.size())
+        if (!data.empty())
         {
             ret += " '";
             ret += printable_directive();
@@ -893,7 +893,7 @@ class OptionList : public std::vector<Option>, public RCCopyable<thread_unsafe_r
         for (std::vector<std::string>::const_iterator i = list.begin(); i != list.end(); ++i)
         {
             const Option opt = Split::by_space<Option, Lex, SpaceMatch, Limits>(*i, lim);
-            if (opt.size())
+            if (!opt.empty())
             {
                 if (lim)
                 {
@@ -940,7 +940,7 @@ class OptionList : public std::vector<Option>, public RCCopyable<thread_unsafe_r
             Option opt;
             opt.reserve(2);
             Split::by_char_void<Option, NullLex, Limits>(opt, line, '=', 0, 1, lim);
-            if (opt.size())
+            if (!opt.empty())
             {
                 if (lim)
                 {
@@ -1019,7 +1019,7 @@ class OptionList : public std::vector<Option>, public RCCopyable<thread_unsafe_r
             else if (!ignore_line(line))
             {
                 Option opt = parse_option_from_line(line, lim);
-                if (opt.size())
+                if (!opt.empty())
                 {
                     if (is_open_tag(opt.ref(0)))
                     {
@@ -1087,7 +1087,7 @@ class OptionList : public std::vector<Option>, public RCCopyable<thread_unsafe_r
                 else if (line.starts_with(prefix))
                 {
                     Option opt = Split::by_char<Option, NullLex, Limits>(std::string(line, prefix.length()), '=', 0, 1, lim);
-                    if (opt.size())
+                    if (!opt.empty())
                     {
                         if (is_open_meta_tag(opt.ref(0)))
                         {

openvpn/common/path.hpp

@@ -60,13 +60,13 @@ inline bool win_dev(const std::string &path, const bool fully_qualified)
 // true if path is fully qualified
 inline bool is_fully_qualified(const std::string &path)
 {
-    return win_dev(path, true) || (path.length() > 0 && is_dirsep(path[0]));
+    return win_dev(path, true) || (!path.empty() && is_dirsep(path[0]));
 }
 
 // does path refer to regular file without directory traversal
 inline bool is_flat(const std::string &path)
 {
-    return path.length() > 0
+    return !path.empty()
            && path != "."
            && path != ".."
            && path.find_first_of(dirsep) == std::string::npos