The provided C program implements a simple command-line utility for...

The provided C program implements a simple command-line utility for managing text documents. Here's what each part of the program does:

Overview:

The program uses system calls to execute operations like creating, listing, reading, and deleting text documents in a specific directory named TEST/. It repetitively interacts with the user through a menu-driven interface until the user chooses to exit.

Key Features and Behavior:

1. Initialization (int main()):

   • The program ensures the directory TEST/ exists by using the mkdir function with permissions 0777.
   • Presents a persistent menu to the user with options to manage documents.

2. Functions:

   • creaDocumento():

     • Prompts the user to provide a document name and its content.
     • Executes a system command to:
       1. Create the file within the TEST/ directory.
       2. Write the provided content into the file.
       • Example command: mkdir -p TEST/ && echo 'content' > TEST/document_name.txt.
     • Displays confirmation that the document has been created.

   • listaDocumenti():

     • Lists all files stored in the TEST/ directory.
     • Executes a system command: ls -1 TEST/, showing one file per line.
     • Displays the list of files to the user.

   • leggiDocumento():

     • Prompts the user to enter the name of a document they want to read (file name without .txt).
     • Executes a system command to display the content of the specified file using cat.
       • Example command: cat TEST/document_name.txt.
     • Displays the content if the file exists.

   • eliminaDocumento():

     • Prompts the user to enter the name of a document they want to delete.
     • Executes a system command to remove the specified file using rm.
       • Example command: rm -f TEST/document_name.txt.
     • Displays a message confirming the deletion of the document if it existed.

3. Menu (do-while loop):

   • Displays the following options on a loop:
     1. Create a document.
     2. List documents.
     3. Read a document.
     4. Delete a document.
     5. Exit the program.
   • Based on the user's input (scelta), calls the corresponding function.
   • If an invalid option is entered, notifies the user before redisplaying the menu.

Notes on Behavior:

• Directory Handling: The program creates the directory TEST/ at the start and saves all files there. It assumes this directory is writable.
• Input Handling: User input is taken using fgets for strings and scanf for integers. The use of strcspn helps remove trailing newline characters that fgets may introduce.
• System Commands: The program heavily relies on system() calls, making it simple but exposing it to potential risks like shell injection if inputs aren't carefully sanitized.
• Permissions: The program assumes the user has appropriate permissions to perform file operations in the current working directory.

Example Interaction:

1. Menu Prompt:

   Gestore Documenti
   1) Crea Documento
   2) Lista Documento
   3) Leggi Documento
   4) Elimina Documento
   5) Finisci Gestione Documenti
   Scelta: 
   

2. Creating a Document (Option 1):

   • User enters document name: doc1
   • User enters content: Hello, World!
   • The program creates TEST/doc1.txt containing the text Hello, World!.

3. Listing Documents (Option 2):

   • The program displays:

     Lista documenti:
     doc1.txt
     

4. Reading a Document (Option 3):

   • User specifies the document doc1.
   • The program displays:

     Contenuto documento:
     Hello, World!
     

5. Deleting a Document (Option 4):

   • User specifies the document doc1.
   • The program removes TEST/doc1.txt and confirms deletion.

6. Exiting (Option 5):

   • The program terminates.

Risks & Potential Issues:

1. Security Risk:

   • Using system() with user input directly introduces vulnerabilities (e.g., shell injection).
   • Inputs like name; rm -rf / or $(rm -rf /) could execute unintended destructive commands.
   • Solution: Avoid system() calls; use dedicated file I/O operations (fopen, fwrite, fread, etc.) for safer functionality.

2. Error Handling:

   • The program doesn't check if the entered documents exist before reading or deleting.
   • It should verify the success of file operations to avoid errors or misleading confirmations.

3. Cross-Platform Compatibility:

   • System commands (mkdir, ls, cat, rm) may not work on non-Unix-based operating systems (e.g., Windows without additional tools).

Summary:

The program is a basic document management system leveraging system commands to create, list, read, and delete text files in a dedicated directory (TEST/). While it demonstrates important programming concepts, it contains vulnerabilities and could be improved by using safer alternatives to system calls.