fix quoted command lines arguments (#306)

Handling of quotes and quotes with leading backslash for command line parsing - UE-231677

1 files changed, 142 insertions, 0 deletions

diff --git a/src/zencore/process.cpp b/src/zencore/process.cpp
index c51e8f69d..0761521dc 100644
--- a/src/zencore/process.cpp
+++ b/src/zencore/process.cpp
@@ -1047,6 +1047,118 @@ FindProcess(const std::filesystem::path& ExecutableImage, ProcessHandle& OutHand
 #endif	// ZEN_PLATFORM_LINUX
 }
 
+std::vector<std::string>
+ParseCommandLine(std::string_view CommandLine)
+{
+	auto IsWhitespaceOrEnd = [](std::string_view CommandLine, std::string::size_type Pos) {
+		if (Pos == CommandLine.length())
+		{
+			return true;
+		}
+		if (CommandLine[Pos] == ' ')
+		{
+			return true;
+		}
+		return false;
+	};
+
+	bool IsParsingArg = false;
+	bool IsInQuote	  = false;
+
+	std::string::size_type	 Pos	  = 0;
+	std::string::size_type	 ArgStart = 0;
+	std::vector<std::string> Args;
+	while (Pos < CommandLine.length())
+	{
+		if (IsInQuote)
+		{
+			if (CommandLine[Pos] == '"' && IsWhitespaceOrEnd(CommandLine, Pos + 1))
+			{
+				Args.push_back(std::string(CommandLine.substr(ArgStart, Pos - ArgStart + 1)));
+				Pos++;
+				IsInQuote	 = false;
+				IsParsingArg = false;
+			}
+			else
+			{
+				Pos++;
+			}
+		}
+		else if (IsParsingArg)
+		{
+			ZEN_ASSERT(Pos > ArgStart);
+			if (CommandLine[Pos] == ' ')
+			{
+				Args.push_back(std::string(CommandLine.substr(ArgStart, Pos - ArgStart)));
+				Pos++;
+				IsParsingArg = false;
+			}
+			else if (CommandLine[Pos] == '"')
+			{
+				IsInQuote = true;
+				Pos++;
+			}
+			else
+			{
+				Pos++;
+			}
+		}
+		else if (CommandLine[Pos] == '"')
+		{
+			IsInQuote	 = true;
+			IsParsingArg = true;
+			ArgStart	 = Pos;
+			Pos++;
+		}
+		else if (CommandLine[Pos] != ' ')
+		{
+			IsParsingArg = true;
+			ArgStart	 = Pos;
+			Pos++;
+		}
+		else
+		{
+			Pos++;
+		}
+	}
+	if (IsParsingArg)
+	{
+		ZEN_ASSERT(Pos > ArgStart);
+		Args.push_back(std::string(CommandLine.substr(ArgStart)));
+	}
+
+	return Args;
+}
+
+std::vector<char*>
+StripCommandlineQuotes(std::vector<std::string>& InOutArgs)
+{
+	std::vector<char*> RawArgs;
+	RawArgs.reserve(InOutArgs.size());
+	for (std::string& Arg : InOutArgs)
+	{
+		std::string::size_type EscapedQuotePos = Arg.find("\\\"", 1);
+		while (EscapedQuotePos != std::string::npos && Arg.rfind('\"', EscapedQuotePos - 1) != std::string::npos)
+		{
+			Arg.erase(EscapedQuotePos, 1);
+			EscapedQuotePos = Arg.find("\\\"", EscapedQuotePos);
+		}
+
+		if (Arg.starts_with("\""))
+		{
+			if (Arg.find('"', 1) == Arg.length() - 1)
+			{
+				if (Arg.find(' ', 1) == std::string::npos)
+				{
+					Arg = Arg.substr(1, Arg.length() - 2);
+				}
+			}
+		}
+		RawArgs.push_back(const_cast<char*>(Arg.c_str()));
+	}
+	return RawArgs;
+}
+
 #if ZEN_WITH_TESTS
 
 void
@@ -1123,6 +1235,36 @@ TEST_CASE("BuildArgV")
 	}
 }
 
+TEST_CASE("CommandLine")
+{
+	std::vector<std::string> v1 = ParseCommandLine("c:\\my\\exe.exe \"quoted arg\" \"one\",two,\"three\\\"");
+	CHECK_EQ(v1[0], "c:\\my\\exe.exe");
+	CHECK_EQ(v1[1], "\"quoted arg\"");
+	CHECK_EQ(v1[2], "\"one\",two,\"three\\\"");
+
+	std::vector<std::string> v2 = ParseCommandLine(
+		"--tracehost 127.0.0.1 builds download --url=https://jupiter.devtools.epicgames.com --namespace=ue.oplog "
+		"--bucket=citysample.packaged-build.fortnite-main.windows \"c:\\just\\a\\path\" "
+		"--access-token-path=\"C:\\Users\\dan.engelbrecht\\jupiter-token.json\" \"D:\\Dev\\Spaced Folder\\Target\\\" "
+		"--alt-path=\"D:\\Dev\\Spaced Folder2\\Target\\\" 07dn23ifiwesnvoasjncasab --build-part-name win64,linux,ps5");
+
+	std::vector<char*> v2Stripped = StripCommandlineQuotes(v2);
+	CHECK_EQ(v2Stripped[0], std::string("--tracehost"));
+	CHECK_EQ(v2Stripped[1], std::string("127.0.0.1"));
+	CHECK_EQ(v2Stripped[2], std::string("builds"));
+	CHECK_EQ(v2Stripped[3], std::string("download"));
+	CHECK_EQ(v2Stripped[4], std::string("--url=https://jupiter.devtools.epicgames.com"));
+	CHECK_EQ(v2Stripped[5], std::string("--namespace=ue.oplog"));
+	CHECK_EQ(v2Stripped[6], std::string("--bucket=citysample.packaged-build.fortnite-main.windows"));
+	CHECK_EQ(v2Stripped[7], std::string("c:\\just\\a\\path"));
+	CHECK_EQ(v2Stripped[8], std::string("--access-token-path=\"C:\\Users\\dan.engelbrecht\\jupiter-token.json\""));
+	CHECK_EQ(v2Stripped[9], std::string("\"D:\\Dev\\Spaced Folder\\Target\""));
+	CHECK_EQ(v2Stripped[10], std::string("--alt-path=\"D:\\Dev\\Spaced Folder2\\Target\""));
+	CHECK_EQ(v2Stripped[11], std::string("07dn23ifiwesnvoasjncasab"));
+	CHECK_EQ(v2Stripped[12], std::string("--build-part-name"));
+	CHECK_EQ(v2Stripped[13], std::string("win64,linux,ps5"));
+}
+
 TEST_SUITE_END(/* core.process */);
 
 #endif