From 42d12a644ed4cb3249ee0b5804f5e6e9ddfe5c6c Mon Sep 17 00:00:00 2001
From: Kawe Mazidjatari <48657826+Mauler125@users.noreply.github.com>
Date: Wed, 5 Jul 2023 21:50:36 +0200
Subject: [PATCH] Fix bug in 'V_StripLastDir' and 'CUtlString::DirName'

In some code paths of 'V_StripLastDir', the string length value was never set. The return type of this function has changed to return always return the length of the new string. An additional bug in 'CUtlString::DirName' has been fixed, where the length was only set if the trailing slashed weren't stripped.
---
 r5dev/public/tier1/strtools.h |  2 +-
 r5dev/tier1/strtools.cpp      | 56 +++++++++++++++++++++--------------
 r5dev/tier1/utlstring.cpp     |  9 +++---
 3 files changed, 38 insertions(+), 29 deletions(-)

diff --git a/r5dev/public/tier1/strtools.h b/r5dev/public/tier1/strtools.h
index 9d7604c3..e1b09264 100644
--- a/r5dev/public/tier1/strtools.h
+++ b/r5dev/public/tier1/strtools.h
@@ -124,7 +124,7 @@ inline void V_MakeAbsolutePath(char* pOut, size_t outLen, const char* pPath, con
 }
 
 // Remove the final directory from the path
-bool V_StripLastDir(char* dirName, size_t maxLen, size_t* newLen);
+size_t V_StripLastDir(char* dirName, size_t maxLen);
 // Returns a pointer to the unqualified file name (no path) of a file name
 const char* V_UnqualifiedFileName(const char* in);
 // Given a path and a filename, composes "path\filename", inserting the (OS correct) separator if necessary
diff --git a/r5dev/tier1/strtools.cpp b/r5dev/tier1/strtools.cpp
index ecb38482..ff6160d2 100644
--- a/r5dev/tier1/strtools.cpp
+++ b/r5dev/tier1/strtools.cpp
@@ -772,19 +772,22 @@ V_MakeAbsolutePath(char* pOut, size_t outLen, const char* pPath, const char* pSt
 // Input  : *dirName - 
 //			maxLen - 
 //			*newLen - 
-// Output : Returns true on success, false on failure.
+// Output : Returns the new length of the string
 //-----------------------------------------------------------------------------
-bool V_StripLastDir(char* dirName, size_t maxLen, size_t* newLen)
+size_t V_StripLastDir(char* dirName, size_t maxLen)
 {
-	if (dirName[0] == 0 ||
-		!V_stricmp(dirName, "./") ||
-		!V_stricmp(dirName, ".\\"))
-		return false;
+	Assert(dirName);
+
+	if (dirName[0] == '\0')
+		return 0;
 
 	size_t len = V_strlen(dirName);
-
 	Assert(len < maxLen);
 
+	if (!V_stricmp(dirName, "./") ||
+		!V_stricmp(dirName, ".\\"))
+		return len;
+
 	// skip trailing slash
 	if (PATHSEPARATOR(dirName[len - 1]))
 	{
@@ -796,9 +799,10 @@ bool V_StripLastDir(char* dirName, size_t maxLen, size_t* newLen)
 	{
 		if (PATHSEPARATOR(dirName[len - 1]))
 		{
-			dirName[len] = 0;
+			dirName[len] = '\0';
 			V_FixSlashes(dirName, CORRECT_PATH_SEPARATOR);
-			return true;
+
+			return len;
 		}
 		else if (dirName[len - 1] == ':')
 		{
@@ -809,27 +813,33 @@ bool V_StripLastDir(char* dirName, size_t maxLen, size_t* newLen)
 	}
 
 	// If we hit a drive letter, then we're done.
-	// Ex: If they passed in c:\, then V_StripLastDir should return "" and false.
+	// Ex: If they passed in c:\, then V_StripLastDir should
+	// turn the string into "" and return 0.
 	if (bHitColon)
 	{
-		dirName[0] = 0;
-		return false;
+		dirName[0] = '\0';
+		return 0;
 	}
 
-	// Allow it to return an empty string and true. This can happen if something like "tf2/" is passed in.
-	// The correct behavior is to strip off the last directory ("tf2") and return true.
-	if (len == 0 && !bHitColon)
+	// Allow it to return an empty string and 0. This can happen if something like "tf2/" is passed in.
+	// The correct behavior is to strip off the last directory ("tf2") and return the new length.
+	if (len == 0)
 	{
-		V_snprintf(dirName, maxLen, ".%c", CORRECT_PATH_SEPARATOR);
-		return true;
+		int ret = V_snprintf(dirName, maxLen, ".%c", CORRECT_PATH_SEPARATOR);
+
+		// snprintf failed, turn the string into "" and return 0.
+		if (ret < 0)
+		{
+			Assert(0);
+
+			dirName[0] = '\0';
+			return 0;
+		}
+
+		return ret;
 	}
 
-	if (newLen)
-	{
-		*newLen = len;
-	}
-
-	return true;
+	return len;
 }
 
 //-----------------------------------------------------------------------------
diff --git a/r5dev/tier1/utlstring.cpp b/r5dev/tier1/utlstring.cpp
index adf4bda5..2a6cf36c 100644
--- a/r5dev/tier1/utlstring.cpp
+++ b/r5dev/tier1/utlstring.cpp
@@ -430,7 +430,8 @@ void CUtlString::StripTrailingSlash()
 
 	int64 nLastChar = Length() - 1;
 	char c = m_Storage[ nLastChar ];
-	if ( c == '\\' || c == '/' )
+
+	if ( PATHSEPARATOR( c ) )
 	{
 		m_Storage[ nLastChar ] = 0;
 		m_Storage.SetLength( m_Storage.Length() - 1 );
@@ -607,14 +608,12 @@ CUtlString CUtlString::UnqualifiedFilename() const
 CUtlString CUtlString::DirName( bool bStripTrailingSlash ) const
 {
 	CUtlString ret( this->String() );
-	size_t len = 0;
+	size_t len = V_StripLastDir( (char*)ret.m_Storage.Get(), ret.m_Storage.Length() );
 
-	V_StripLastDir( (char*)ret.m_Storage.Get(), ret.m_Storage.Length(), &len );
+	ret.SetLength( len );
 
 	if (bStripTrailingSlash)
 		ret.StripTrailingSlash();
-	else
-		ret.SetLength(len); // StripTrailingSlash sets this, but if we skip it then nothing sets it.
 
 	return ret;
 }