Edits to list_files func, function header

include/pros/misc.h

@@ -742,7 +742,12 @@ int32_t usd_is_installed(void);
  * ENOBUFS - drive has no work area
  * ENFILE - too many open files
  * 
- * 
+ * \param path
+ * 	  The path to the directory to list files in
+ * \param buffer
+ * 	  The buffer to put the file names into
+ * \param len
+ * 	  The length of the buffer
  *  
  * \note use a path of "\" to list the files in the main directory NOT "/usd/"
  *  DO NOT PREPEND YOUR PATHS WITH "/usd/"

include/pros/misc.hpp

@@ -546,7 +546,12 @@ Lists the files in a directory specified by the path
  * ENOBUFS - drive has no work area
  * ENFILE - too many open files
  * 
- * 
+ * \param path
+ * 	  The path to the directory to list files in
+ * \param buffer
+ * 	  The buffer to put the file names into
+ * \param len
+ * 	  The length of the buffer
  *  
  * \note use a path of "\" to list the files in the main directory NOT "/usd/"
  *  DO NOT PREPEND YOUR PATHS WITH "/usd/"
@@ -589,7 +594,12 @@ Lists the files in a directory specified by the path
  * ENOBUFS - drive has no work area
  * ENFILE - too many open files
  * 
- * 
+ * \param path
+ * 	  The path to the directory to list files in
+ * \param buffer
+ * 	  The buffer to put the file names into
+ * \param len
+ * 	  The length of the buffer
  *  
  * \note use a path of "\" to list the files in the main directory NOT "/usd/"
  *  DO NOT PREPEND YOUR PATHS WITH "/usd/"
@@ -606,9 +616,9 @@ Lists the files in a directory specified by the path
  *	pros::delay(200);
  *	// Given vector of std::string file names, print each file name
  *  // Note that if there is an error, the vector will contain one element, which
- * // is the error state
+ *  // is the error state
  *  // Print each file name
- *	for (std::string file : files) {
+ *	for (std::string& file : files) {
  *		std::cout << file << std::endl;
  *	}
  * }

src/devices/vdml_usd.cpp

@@ -71,29 +71,30 @@ std::vector<std::string> list_files(const char* path, char* buffer, int32_t len)
 		}
 		return files;
 	}
+
 	// Parse buffer given call successful, split by '/n'
-	// Store char * buffer as std::string in str
-	// Store delimiter in std::string, '\n'
-	std::string str(buffer);
-	std::string delimiter = "\n";
+	std::string_view str(buffer);
 
-	// position to keep track of position in str
+	// delimter_pos is the position of the delimiter '\n'
+	// index of which character to start substr from
 	// file_name used to store each file name
-	size_t position = 0;
-	std::string file_name;
+	size_t delimiter_pos, index = 0;
+	std::string_view file_name;
 
 	// Loop until delimiter '\n' can not be found anymore
-	while ((position = str.find(delimiter)) != std::string::npos) {
+	while ((delimiter_pos = str.find('\n', index)) != std::string::npos) {
 		// file_name is the string from the beginning of str to the first '\n', excluding '\n'
-		file_name = str.substr(0, position);
+		file_name = std::string_view(str.data() + index, delimiter_pos - index);
 		// Add token to files vector
-		files.push_back(file_name);
-		// Erase file_name from str, would be pos + 1 if we wanted to include '\n'
-		str.erase(0, position + 1);
-	}
+		files.emplace_back(file_name);
+		// Increment index to start substr from
+		index = delimiter_pos + 1;
 
-	// return vector of file names
-	return files;
+		// If index is greater than or equal to str length, break
+		if (index >= str.length()) {
+			break;
+		}
+	}
 }
 
 }  // namespace usd