MultiUser-Unix-FileSystem

Introduction

A UNIX-based second level file system that supports concurrent shell access by multiple users

Our work

• Used an image file as virtual disk, realizing the function of mutual cross-system reading and writing files
• Created session to achieve multi-user parallel access, implementing the communication between shell and host
• Used BSD (flock) lock control file reading and writing permissions, supporting multithread access to the file system at the same time
• For more information, refer to Project report.

Install

Compile with Integrated environment

• The VS2019 x86 integrated environment is recommended for compilation. The x64 version is not supported.
• Create the two folders Host and Client as two projects and compile them to generate Host.exe and Client.exe, respectively.
• For faster start, the Windows x86 running versions of both files have been published in this folder.

Makefile

• The Makefile.win file has the preset environment path. Therefore, you need to change the g++ environment path of Makefile.win in the Host and Client folders to run the compilation correctly. You need to change the following LIBS, INCS, and CXXINCS directory paths.

CPP      = g++.exe -D__DEBUG__
CC       = gcc.exe -D__DEBUG__
WINDRES  = windres.exe
OBJ      = client.o
LINKOBJ  = client.o
LIBS     = -L"C:/C++/Dev C++/Dev-Cpp/MinGW64/x86_64-w64-mingw32/lib32" -lws2_32 -m32 -g3
INCS     = -I"C:/C++/Dev C++/Dev-Cpp/MinGW64/include" -I"C:/C++/Dev C++/Dev-Cpp/MinGW64/x86_64-w64-mingw32/include" -I"C:/C++/Dev C++/Dev-Cpp/MinGW64/lib/gcc/x86_64-w64-mingw32/4.9.2/include"
CXXINCS  = -I"C:/C++/Dev C++/Dev-Cpp/MinGW64/include" -I"C:/C++/Dev C++/Dev-Cpp/MinGW64/x86_64-w64-mingw32/include" -I"C:/C++/Dev C++/Dev-Cpp/MinGW64/lib/gcc/x86_64-w64-mingw32/4.9.2/include" -I"C:/C++/Dev C++/Dev-Cpp/MinGW64/lib/gcc/x86_64-w64-mingw32/4.9.2/include/c++"
BIN      = cilent.exe
CXXFLAGS = $(CXXINCS) -m32 -std=c++11 -g3
CFLAGS   = $(INCS) -m32 -std=c++11 -g3
RM       = rm.exe -f
 
.PHONY: all all-before all-after clean clean-custom
 
all: all-before $(BIN) all-after
 
clean: clean-custom
	${RM} $(OBJ) $(BIN)
 
$(BIN): $(OBJ)
	$(CPP) $(LINKOBJ) -o $(BIN) $(LIBS)
 
client.o: client.cpp
	$(CPP) -c client.cpp -o client.o $(CXXFLAGS)

• And run the following to compile

mingw32-make.exe -f ".\Makefile.win" clean all

A running example

1. First, run Host.exe and then Client.exe to log in as a user

• 

2. Connect to the Host and Login. The default account is root(for both name and password) and run fformat to format the hard disk

• 

3. Run auto to run automatic tests

• 

4. Open another client and log in to test concurrency

• 

5. Use another client to try to open an unauthorized file

• 

6. Use another client to try a file that was locked by the previous client

• 

7. After the previous client closes the file (unlock it), the other client can access the file

• 

8. Exit To save the file to img
9. Here is the file of the test output

•