src: refactor SplitString in util

nodejs · nodejs-github-bot · Jun 22, 2023 · Jun 18, 2023 · Jun 22, 2023 · Jun 22, 2023
commit b53ae22f5c493ccdc4ff40bb139b5a06bd0cb740
diff --git a/src/node_options.cc b/src/node_options.cc
@@ -50,11 +50,13 @@ void DebugOptions::CheckOptions(std::vector<std::string>* errors,
                       "`node --inspect-brk` instead.");
   }
 
-  std::vector<std::string> destinations =
-      SplitString(inspect_publish_uid_string, ',');
+  std::vector<std::string_view> destinations =
+      SplitString(std::string_view(inspect_publish_uid_string.c_str(),
+                                   inspect_publish_uid_string.size()),
+                  ",");
   inspect_publish_uid.console = false;
   inspect_publish_uid.http = false;
-  for (const std::string& destination : destinations) {
+  for (const std::string_view destination : destinations) {
     if (destination == "stderr") {
       inspect_publish_uid.console = true;
     } else if (destination == "http") {

diff --git a/src/node_v8_platform-inl.h b/src/node_v8_platform-inl.h
@@ -129,8 +129,9 @@ struct V8Platform {
     // Attach a new NodeTraceWriter only if this function hasn't been called
     // before.
     if (tracing_file_writer_.IsDefaultHandle()) {
-      std::vector<std::string> categories =
-          SplitString(per_process::cli_options->trace_event_categories, ',');
+      auto out = per_process::cli_options->trace_event_categories;
+      std::vector<std::string_view> categories =
+          SplitString(std::string_view(out.c_str(), out.size()), ",");
 
       tracing_file_writer_ = tracing_agent_->AddClient(
           std::set<std::string>(std::make_move_iterator(categories.begin()),

diff --git a/src/permission/fs_permission.cc b/src/permission/fs_permission.cc
@@ -74,7 +74,8 @@ namespace permission {
 // allow = '*'
 // allow = '/tmp/,/home/example.js'
 void FSPermission::Apply(const std::string& allow, PermissionScope scope) {
-  for (const auto& res : SplitString(allow, ',')) {
+  for (const auto res :
+       SplitString(std::string_view(allow.c_str(), allow.size()), ",")) {
     if (res == "*") {
       if (scope == PermissionScope::kFileSystemRead) {
         deny_all_in_ = false;
@@ -85,7 +86,7 @@ void FSPermission::Apply(const std::string& allow, PermissionScope scope) {
       }
       return;
     }
-    GrantAccess(scope, res);
+    GrantAccess(scope, std::string(res.data(), res.size()));
   }
 }
 

diff --git a/src/util.cc b/src/util.cc
@@ -169,19 +169,21 @@ std::string GetHumanReadableProcessName() {
   return SPrintF("%s[%d]", GetProcessTitle("Node.js"), uv_os_getpid());
 }
 
-std::vector<std::string> SplitString(const std::string& in,
-                                     char delim,
-                                     bool skipEmpty) {
-  std::vector<std::string> out;
-  if (in.empty())
-    return out;
-  std::istringstream in_stream(in);
-  while (in_stream.good()) {
-    std::string item;
-    std::getline(in_stream, item, delim);
-    if (item.empty() && skipEmpty) continue;
-    out.emplace_back(std::move(item));
+std::vector<std::string_view> SplitString(const std::string_view in,
+                                          const std::string_view delim) {
+  std::vector<std::string_view> out;
+
+  for (auto first = in.data(), second = in.data(), last = first + in.size();
+       second != last && first != last;
+       first = second + 1) {
+    second =
+        std::find_first_of(first, last, std::cbegin(delim), std::cend(delim));
+
+    if (first != second) {
+      out.emplace_back(first, second - first);
+    }
   }
+
   return out;
 }
 

diff --git a/src/util.h b/src/util.h
@@ -685,9 +685,8 @@ struct FunctionDeleter {
 template <typename T, void (*function)(T*)>
 using DeleteFnPtr = typename FunctionDeleter<T, function>::Pointer;
 
-std::vector<std::string> SplitString(const std::string& in,
-                                     char delim,
-                                     bool skipEmpty = true);
+std::vector<std::string_view> SplitString(const std::string_view in,
+                                          const std::string_view delim);
 
 inline v8::MaybeLocal<v8::Value> ToV8Value(v8::Local<v8::Context> context,
                                            std::string_view str,