lib/mp-readline: Add n_chars argument to mp_hal_erase_line_from_cursor.

dpgeorge · dpgeorge · commit f961456b29a6 · 2015-10-20T13:27:14.000+01:00
If VT100 support is not available then a given implementation of
mp_hal_erase_line_from_cursor might need to know the number of characters
to erase.

This patch does not change generated code when VT100 is supported, since
compiler can optimise away the argument.
diff --git a/lib/mp-readline/readline.c b/lib/mp-readline/readline.c
@@ -82,7 +82,8 @@ STATIC void mp_hal_move_cursor_back(uint pos) {
     }
 }
 
-STATIC void mp_hal_erase_line_from_cursor(void) {
+STATIC void mp_hal_erase_line_from_cursor(uint n_chars_to_erase) {
+    (void)n_chars_to_erase;
     mp_hal_stdout_tx_strn("\x1b[K", 3);
 }
 #endif
@@ -338,8 +339,7 @@ int readline_process_char(int c) {
     if (redraw_from_cursor) {
         if (rl.line->len < last_line_len) {
             // erase old chars
-            // (number of chars to erase: last_line_len - rl.cursor_pos)
-            mp_hal_erase_line_from_cursor();
+            mp_hal_erase_line_from_cursor(last_line_len - rl.cursor_pos);
         }
         // draw new chars
         mp_hal_stdout_tx_strn(rl.line->buf + rl.cursor_pos, rl.line->len - rl.cursor_pos);
diff --git a/windows/windows_mphal.c b/windows/windows_mphal.c
@@ -92,7 +92,7 @@ void mp_hal_move_cursor_back(uint pos) {
     SetConsoleCursorPosition(con_out, info.dwCursorPosition);
 }
 
-void mp_hal_erase_line_from_cursor() {
+void mp_hal_erase_line_from_cursor(uint n_chars_to_erase) {
     assure_conout_handle();
     CONSOLE_SCREEN_BUFFER_INFO info;
     GetConsoleScreenBufferInfo(con_out, &info);
diff --git a/windows/windows_mphal.h b/windows/windows_mphal.h
@@ -29,4 +29,4 @@
 #define MICROPY_HAL_HAS_VT100 (0)
 
 void mp_hal_move_cursor_back(unsigned int pos);
-void mp_hal_erase_line_from_cursor();
+void mp_hal_erase_line_from_cursor(unsigned int n_chars_to_erase);

Original file line number	Diff line number	Diff line change
`@@ -82,7 +82,8 @@ STATIC void mp_hal_move_cursor_back(uint pos) {`
`82`	`82`	`}`
`83`	`83`	`}`
`84`	`84`
`85`		`-STATIC void mp_hal_erase_line_from_cursor(void) {`
	`85`	`+STATIC void mp_hal_erase_line_from_cursor(uint n_chars_to_erase) {`
	`86`	`+ (void)n_chars_to_erase;`
`86`	`87`	`mp_hal_stdout_tx_strn("\x1b[K", 3);`
`87`	`88`	`}`
`88`	`89`	`#endif`
`@@ -338,8 +339,7 @@ int readline_process_char(int c) {`
`338`	`339`	`if (redraw_from_cursor) {`
`339`	`340`	`if (rl.line->len < last_line_len) {`
`340`	`341`	`// erase old chars`
`341`		`- // (number of chars to erase: last_line_len - rl.cursor_pos)`
`342`		`- mp_hal_erase_line_from_cursor();`
	`342`	`+ mp_hal_erase_line_from_cursor(last_line_len - rl.cursor_pos);`
`343`	`343`	`}`
`344`	`344`	`// draw new chars`
`345`	`345`	`mp_hal_stdout_tx_strn(rl.line->buf + rl.cursor_pos, rl.line->len - rl.cursor_pos);`
Original file line number	Diff line number	Diff line change
`@@ -92,7 +92,7 @@ void mp_hal_move_cursor_back(uint pos) {`
`92`	`92`	`SetConsoleCursorPosition(con_out, info.dwCursorPosition);`
`93`	`93`	`}`
`94`	`94`
`95`		`-void mp_hal_erase_line_from_cursor() {`
	`95`	`+void mp_hal_erase_line_from_cursor(uint n_chars_to_erase) {`
`96`	`96`	`assure_conout_handle();`
`97`	`97`	`CONSOLE_SCREEN_BUFFER_INFO info;`
`98`	`98`	`GetConsoleScreenBufferInfo(con_out, &info);`