More on curses and program structure...

chapters/chapter_2.c

@@ -162,14 +162,64 @@ int curses_screen_width  = 0;
 int curses_screen_height = 0;
 int curses_active        = 1;
 
-static void curses_deinitialize (void) {
-	curses_screen    = deallocate (curses_screen);
+/*
+I need to quickly explain how I'm structuring this subprogram. You can think of functions and variables starting with 'curses_*' as tiny standalone library if it's easier. They
+deal with terminal input and output. User only needs to call function 'curses_configure' only once, before doing any rendering, then make an "infinite" loop that'll stop when
+external variable 'curses_active' is equal to zero. In that loop, user can call any 'curses_render_*' function, and at the end call function 'curses_synchronize' only once. So the
+following program structure would look something like this:
+
+@C
+// ...
+int main (int argc, char * * argv) {
+	// ...
+	curses_configure ();
+
+	while (curses_active != 0) { // Notice the negative condition, the loop will stop then the condition is 0, so when 'curses_active' is 0.
+		// Calling functions 'curses_render_*' and doing other work...
+		curses_synchronize ();
+	}
+
+	// ...
+	return (0);
+}
+@
+*/
+
+static void curses_initialize (void) {                                                           // This function will be called when 'curses_configure' is called, automatically.
+	struct winsize screen_dimension;
+
+	fatal_failure (ioctl (STDOUT_FILENO, TIOCGWINSZ, & screen_dimension) == -1,              // If function 'ioctl' failed, we immediately aborting the entire program.
+	               "ioctl: Failed to get terminal dimensions.");                             // I split those error messages, you can find your own formatting style.
+
+	curses_screen_width  = (int) screen_dimension.ws_col;                                    // We get the dimensions of terminal window by calling that 'ioctl' function.
+	curses_screen_height = (int) screen_dimension.ws_row;
+
+	fatal_failure (tcgetattr (STDIN_FILENO, & curses_old_terminal) == -1,                    // Now we need to obtain data for current non-raw terminal to restore it later.
+	               "tcgetattr: Failed to get default terminal attributes.");
+
+	curses_new_terminal = curses_old_terminal;                                               // Here we set our raw terminal to be the same as the non-raw one.
+
+	curses_new_terminal.c_cc [VMIN]  = (unsigned char) 0;
+	curses_new_terminal.c_cc [VTIME] = (unsigned char) 1;
+
+	curses_new_terminal.c_iflag &= (unsigned int) ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON); // Now it's time to modify it to be raw, this essentially means no-echo.
+	curses_new_terminal.c_oflag &= (unsigned int) ~(OPOST);
+	curses_new_terminal.c_cflag |= (unsigned int)  (CS8);
+	curses_new_terminal.c_lflag &= (unsigned int) ~(ECHO | ICANON | IEXTEN | ISIG);
+
+	fatal_failure (tcsetattr (STDIN_FILENO, TCSAFLUSH, & curses_new_terminal) == -1,         // Finally, we're passing intormations to our terminal, and it becomes raw.
+	               "tcsetattr: Failed to set reverse terminal attributes.");
+}
+
+static void curses_deinitialize (void) {                                                 // This function will be only called once, automatically, at the program exit.
+	curses_screen    = deallocate (curses_screen);                                   // It's important to deallocate all previously allocated memory.
 	curses_activator = deallocate (curses_activator);
 	curses_action    = deallocate (curses_action);
 
-	terminal_clear ();
+	terminal_clear ();                                                               // This only make things look prettier, we don't have mess when we exit the program.
 
-	fatal_failure (tcsetattr (STDIN_FILENO, TCSAFLUSH, & curses_old_terminal) == -1, "tcsetattr: Failed to set default terminal attributes.");
+	fatal_failure (tcsetattr (STDIN_FILENO, TCSAFLUSH, & curses_old_terminal) == -1, // Again, if this fails, we're doomed, we're aborting.
+	               "tcsetattr: Failed to set default terminal attributes.");
 }
 
 static char * curses_screen_offset (int x, int y) {
@@ -223,28 +273,9 @@ External function definitions, those found in "chapter_2.h" header file.
 */
 
 void curses_configure (void) {
-	struct winsize screen_dimension;
-
 	atexit (curses_deinitialize);
 
-	fatal_failure (ioctl (STDOUT_FILENO, TIOCGWINSZ, & screen_dimension) == -1, "ioctl: Failed to get terminal dimensions.");
-
-	curses_screen_width  = (int) screen_dimension.ws_col;
-	curses_screen_height = (int) screen_dimension.ws_row;
-
-	fatal_failure (tcgetattr (STDIN_FILENO, & curses_old_terminal) == -1, "tcgetattr: Failed to get default terminal attributes.");
-
-	curses_new_terminal = curses_old_terminal;
-
-	curses_new_terminal.c_cc [VMIN]  = (unsigned char) 0;
-	curses_new_terminal.c_cc [VTIME] = (unsigned char) 1;
-
-	curses_new_terminal.c_iflag &= (unsigned int) ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
-	curses_new_terminal.c_oflag &= (unsigned int) ~(OPOST);
-	curses_new_terminal.c_cflag |= (unsigned int)  (CS8);
-	curses_new_terminal.c_lflag &= (unsigned int) ~(ECHO | ICANON | IEXTEN | ISIG);
-
-	fatal_failure (tcsetattr (STDIN_FILENO, TCSAFLUSH, & curses_new_terminal) == -1, "tcsetattr: Failed to set reverse terminal attributes.");
+	curses_initialize ();
 
 	curses_screen = allocate (CURSES_REVERT + CURSES_FORMAT * curses_screen_width * curses_screen_height + CURSES_CURSOR + 1);
 

xhartae.c

@@ -93,13 +93,16 @@ One sane C program should have the following structure (please keep in mind that
 */
 
 int main (int argc, char * * argv) {
-	int i;
-
 	(void) argc;
 	(void) argv;
 
-	for (i = 0; i != (int) (sizeof (hello_world) / sizeof (* hello_world)); ++i) {
-		hello_world [i] ();
+	curses_configure ();
+
+	while (curses_active != 0) {
+		curses_render_background ('.', COLOUR_GREY, EFFECT_BOLD);
+		curses_render_character  ('@', COLOUR_RED, EFFECT_BOLD, 1, 1);
+
+		curses_synchronize ();
 	}
 
 	return (EXIT_SUCCESS);