- Refactored the escape sequence parsing, and handling.

  It now uses a struct to store the escape sequence.

  Before it handles the escape sequence, it parses it,
  which includes things like getting any arguments
  that are supplied, and getting the mode type.

- Moved the code that handles control codes to a
  separate function.

The reason for doing this was because I wanted to make
the escape sequence handling faster, but also make the
code more readable at the same time.

I got the idea to do this from st, a terminal emulator
created by the suckless.org project.

1 files changed, 186 insertions, 142 deletions

diff --git a/io.c b/io.c
index ef491f5..37116df 100644
--- a/io.c
+++ b/io.c
@@ -1,11 +1,25 @@
 #include "sux.h"
 
+#define BETWEEN(x, a, b) ((a) <= (x) && (x) <= (b))
+#define DEFAULT(a, b) (a) = (a) ? (a) : (b)
+
 char *key = NULL;
 uint8_t key_idx = 0;
 
-uint8_t iscol;
-uint8_t idx = 3;
-uint8_t bcd[4];
+uint8_t esc = 0;
+uint8_t iscsi = 0;
+
+typedef struct escape escape;
+
+struct escape {
+	char buf[128];		/* Buffer. */
+	size_t len;		/* Buffer length. */
+	int arg[16];		/* Arguments. */
+	int narg;		/* Number of arguments. */
+	char mode[2];		/* Mode type. */
+};
+
+escape escseq;
 
 static inline char *get_keyseq(int keycode) {
 	switch (keycode) {
@@ -115,9 +129,165 @@ int get_key(WINDOW *scr) {
 	return c;
 }
 
+void parse_esc() {
+	char *str = escseq.buf, *nstr;
+	long int value;
+	escseq.narg = 0;
 
-void io(uint64_t address, uint8_t rw) {
+	escseq.buf[escseq.len] = '\0';
+	for (;str < escseq.buf + escseq.len; str++) {
+		nstr = NULL;
+		value = strtol(str, &nstr, 10);
+		if (nstr == str) {
+			value = 0;
+		}
+		if (value == LONG_MAX || value == LONG_MIN) {
+			value = -1;
+		}
+		escseq.arg[escseq.narg++] = value;
+		str = nstr;
+		if (*str != ';' || escseq.narg == 16) {
+			break;
+		}
+	}
+	escseq.mode[0] = *str++;
+	escseq.mode[1] = (str < (escseq.buf + escseq.len)) ? *str : '\0';
+}
+
+void handle_esc() {
 	int x, y;
+	getyx(scr, y, x);
+	switch (escseq.mode[0]) {
+		case 'A':
+			DEFAULT(escseq.arg[0], 1);
+			if (y-escseq.arg[0] >= 0) {
+				y -= escseq.arg[0];
+				#if !debug
+				wmove(scr, y, x);
+				#endif
+			}
+			break;
+		case 'B':
+		case 'e':
+			DEFAULT(escseq.arg[0], 1);
+			if (y+escseq.arg[0] <= getmaxy(scr)) {
+				y += escseq.arg[0];
+				#if !debug
+				wmove(scr, y, x);
+				#endif
+			}
+			break;
+		case 'C':
+		case 'a':
+			DEFAULT(escseq.arg[0], 1);
+			if (x+escseq.arg[0] <= getmaxx(scr)) {
+				x += escseq.arg[0];
+				#if !debug
+				wmove(scr, y, x);
+				#endif
+			}
+			break;
+		case 'D':
+			DEFAULT(escseq.arg[0], 1);
+			if (x-escseq.arg[0] >= 0) {
+				x -= escseq.arg[0];
+				#if !debug
+				wmove(scr, y, x);
+				#endif
+			}
+			break;
+		case 'H':
+		case 'f':
+			DEFAULT(escseq.arg[0], 1);
+			DEFAULT(escseq.arg[1], 1);
+			#if !debug
+			wmove(scr, escseq.arg[0]-1, escseq.arg[1]-1);
+			#else
+			wmove(scr, 31, 0);
+			wclrtoeol(scr);
+			wprintw(scr, "escseq.arg[0]: %i, escseq.arg[1]: %i", escseq.arg[0], escseq.arg[1]);
+			#endif
+			break;
+		case 'S':
+			DEFAULT(escseq.arg[0], 1);
+			#if !debug
+			wscrl(scr, -escseq.arg[0]);
+			#else
+			#endif
+			break;
+		case 'T':
+			DEFAULT(escseq.arg[0], 1);
+			#if !debug
+			wscrl(scr, escseq.arg[0]);
+			#else
+			#endif
+			break;
+	}
+}
+
+void reset_esc() {
+	memset(&escseq, 0, sizeof(escseq));
+}
+
+void handle_ctrlcode(int c) {
+	int x, y;
+	getyx(scr, y, x);
+	switch (c) {
+		case 0xC:
+			x=0,y=0;
+			#if !debug
+			wclear(scr);
+			wmove(scr, y, x);
+			#endif
+			break;
+		case CURSES_BACKSPACE:
+		case '\b':
+			if (x > 0) {
+				x--;
+				#if !debug
+				wmove(scr, y, x);
+				#endif
+			}
+			#if !debug
+			wdelch(scr);
+			#else
+			if (!subdbg) {
+				scr_col++;
+				wmove(scr, 28, scr_col--);
+				wdelch(scr);
+				wmove(scr, 28, scr_col);
+				wdelch(scr);
+			}
+			#endif
+			break;
+		case '\033': reset_esc(); esc = 1; break;
+		case '\n':
+			x = 0;
+			y+=1;
+			#if !debug
+			wmove(scr, y, x);
+			#endif
+			break;
+		default:
+			#if !debug
+			/*wmove(scr, y, x);*/
+			waddch(scr, c);
+			#else
+			if (!subdbg && scr_col < 160) {
+				if (c != ' ') {
+					wprintw(scr, "%02X", c);
+				} else {
+					wprintw(scr, "  ");
+				}
+			}
+			#endif
+			x+=1;
+			break;
+	}
+}
+
+
+void io(uint64_t address, uint8_t rw) {
 	uint16_t scr_col = 0;
 	/*step |= (!rw) ? (cpu->pc[thread] == CTRL_ADDR) : step;*/
 	switch (address) {
@@ -135,7 +305,6 @@ void io(uint64_t address, uint8_t rw) {
 			if (rw) {
 				break;
 			}
-			getyx(scr, y, x);
 			#if debug
 			if (!subdbg) {
 				scr_col = (addr[TX_ADDR] != 0x0C && addr[TX_ADDR] != '\n' && scr_col < 160) ? (addr[1] << 1)-2 : 0;
@@ -148,146 +317,21 @@ void io(uint64_t address, uint8_t rw) {
 					wclrtoeol(scr);
 				}
 				#endif
-				switch (addr[TX_ADDR]) {
-					case 'A':
-						if (y > 0)
-							y--;
-						#if !debug
-						wmove(scr, y, x);
-						#endif
-						esc = 0;
-						break;
-					case 'B':
-						if (y < getmaxy(scr))
-							y++;
-						#if !debug
-						wmove(scr, y, x);
-						#endif
+				int c = addr[TX_ADDR];
+				if (iscsi) {
+					escseq.buf[escseq.len++] = c;
+					if (BETWEEN(c, 0x40, 0x7E) || escseq.len >= sizeof(escseq.buf)-1) {
 						esc = 0;
-						break;
-					case 'C':
-						if (x < getmaxx(scr))
-							x++;
-						#if !debug
-						wmove(scr, y, x);
-						#endif
-						esc = 0;
-						break;
-					case 'D':
-						if (x > 0)
-							x--;
-						#if !debug
-						wmove(scr, y, x);
-						#endif
-						esc = 0;
-						break;
-					case 'H':
-						if (!bcd[2] && !bcd[3]) {
-							y = 0;
-						} else {
-							y = ((bcd[3]*10) + bcd[2]);
-						}
-						if (!bcd[0] && !bcd[1]) {
-							x = 0;
-						} else {
-							x = ((bcd[1]*10) + bcd[0]);
-						}
-						#if !debug
-						wmove(scr, y, x);
-						#else
-						/*mvwprintw(scr, 31, 0, "x: %i, y: %i  ", x, y);*/
-						mvwprintw(scr, 31, 0, "bcd[3-2]: {%u, %u}, bcd[1-0]: {%u, %u}", bcd[3], bcd[2], bcd[1], bcd[0]);
-						#endif
-						idx = 3;
-						bcd[0] = 0;
-						bcd[1] = 0;
-						bcd[2] = 0;
-						bcd[3] = 0;
-						esc = 0;
-						break;
-					case 'S':
-						#if !debug
-						wscrl(scr, -1);
-						#else
-						#endif
-						esc = 0;
-						break;
-					case 'T':
-						#if !debug
-						wscrl(scr, 1);
-						#else
-						#endif
-						esc = 0;
-						break;
-					case '0':
-					case '1':
-					case '2':
-					case '3':
-					case '4':
-					case '5':
-					case '6':
-					case '7':
-					case '8':
-					case '9':
-						bcd[idx--] = (addr[address] - '0');
-						break;
-					default:
-						iscol = (addr[address] == ';');
-						break;
+						iscsi = 0;
+						parse_esc();
+						handle_esc();
+					}
 				}
-			} else {
-				switch (addr[TX_ADDR]) {
-					case 0xC:
-						x=0,y=0;
-						#if !debug
-						wclear(scr);
-						wmove(scr, y, x);
-						#endif
-						break;
-					case CURSES_BACKSPACE:
-					case '\b':
-						if (x > 0) {
-							x--;
-							#if !debug
-							wmove(scr, y, x);
-							#endif
-						}
-						#if !debug
-						wdelch(scr);
-						#else
-						if (!subdbg) {
-							scr_col++;
-							wmove(scr, 28, scr_col--);
-							wdelch(scr);
-							wmove(scr, 28, scr_col);
-							wdelch(scr);
-						}
-						#endif
-						break;
-					case '\033': esc = 1; break;
-					case '\n':
-						x = 0;
-						y+=1;
-						#if !debug
-						wmove(scr, y, x);
-						#endif
-						break;
-					default:
-						#if !debug
-						/*wmove(scr, y, x);*/
-						waddch(scr, addr[address]);
-						#else
-						if (!subdbg && scr_col < 160) {
-							if (addr[address] != ' ') {
-								wprintw(scr, "%02X", addr[address]);
-							} else {
-								wprintw(scr, "  ");
-							}
-						}
-						#endif
-						x+=1;
-						break;
+				if (c == '[') {
+					iscsi = 1;
 				}
+			} else {
+				handle_ctrlcode(addr[TX_ADDR]);
 			}
 			break;
 	}