now the password is hidden

Readme.org

@@ -89,7 +89,7 @@ In that code now we have two users: ~lain~ with the settings we mentioned before
 and a new user ~alyssa~ that will execute commands as ~dbuser~ and ~PERM_PASSWD~ will
 make that she has to enter her password every time she runs ~beroot~.
 
-** TODO
+** TO-DO List
 
 I don't want to make this a big program, I want to keep everything as simple as
 possible, but there are some things that I want to do:
@@ -97,6 +97,5 @@ possible, but there are some things that I want to do:
   standard library.
 - Some kind of persistency (there can be a ~PERM_PERSIST~ flag) so the password
   doesn't need to be entered every time.
-- Hide the password while it's being typed.
 
 Those are the only things I have planned adding to beroot.

src/main.c

@@ -7,6 +7,8 @@
 #include <shadow.h>
 #include <unistd.h>
 
+#include <termios.h>
+
 #include "config.h"
 
 void
@@ -104,6 +106,30 @@ execute (char **command)
 	commands = NULL;
 }
 
+void
+get_password (char *password)
+{
+	if (!password)
+		return;
+
+	static struct termios old_t = { 0 }, new_t = { 0 };
+	tcgetattr (STDIN_FILENO, &old_t);
+	new_t = old_t;
+	new_t.c_lflag &= ~(ECHO);
+	tcsetattr (STDIN_FILENO, TCSANOW, &new_t);
+
+	int i = 0;
+	char c = '\0';
+	while ((c = getchar ()) != '\n' && c != EOF && i < LOGIN_PASSWD_MAX)
+		{
+			password[i++] = c;
+		}
+	password[i] = '\0';
+
+	tcsetattr (STDIN_FILENO, TCSANOW, &old_t);
+	puts (""); // the \n character is not printed anymore
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -150,10 +176,12 @@ main (int argc, char *argv[])
 	else if (user->permissions & PERM_PASSWD)
 		{
 			printf ("Enter the %s password: ", user->target_user);
-			char entered_password[LOGIN_PASSWD_MAX] = { 0 };
-			fgets (entered_password, LOGIN_PASSWD_MAX - 1, stdin);
+			char *entered_password = calloc (sizeof (char), LOGIN_PASSWD_MAX);
+			get_password (entered_password);
 			is_authenticated
 					= authenticate_user (target_swpd->sp_pwdp, entered_password);
+
+			free (entered_password);
 		}
 	else
 		{