Incremental search

kilo.c

@@ -69,7 +69,7 @@ struct editorConfig E;
 
 void editorSetStatusMessage(const char *fmt, ...);
 void editorRefreshScreen();
-char *editorPrompt(char *prompt);
+char *editorPrompt(char *prompt, void (*callback)(char *, int));
 
 /*** terminal ***/
 
@@ -269,6 +269,27 @@ int editorRowCxToRx(erow *row, int cx)
 	return rx;
 }
 
+int editorRowRxToCx(erow *row, int rx)
+{
+	int cur_rx = 0;
+	int cx;
+	for (cx = 0; cx < row->size; cx++)
+	{
+		if (row->chars[cx] == '\t')
+		{
+			cur_rx += (KILO_TAB_STOP - 1) - (cur_rx % KILO_TAB_STOP);
+		}
+		cur_rx++;
+
+		if (cur_rx > rx)
+		{
+			return rx;
+		}
+	}
+
+	return cx;
+}
+
 void editorUpdateRow(erow *row)
 {
 	int tabs = 0;
@@ -501,7 +522,7 @@ void editorSave()
 {
 	if (E.filename == NULL)
 	{
-		E.filename = editorPrompt("Save as: %s (ESC to cancel)");
+		E.filename = editorPrompt("Save as: %s (ESC to cancel)", NULL);
 		if (E.filename == NULL)
 		{
 			editorSetStatusMessage("Save aborted");
@@ -532,6 +553,87 @@ void editorSave()
 	editorSetStatusMessage("Can't save! I/O error: %s", strerror(errno));
 }
 
+/*** find ***/
+
+void editorFindCallback(char *query, int key)
+{
+	static int last_match = -1;
+	static int direction = 1;
+
+	if (key == '\r' || key == '\x1b')
+	{
+		last_match = -1;
+		direction = 1;
+		return;
+	}
+	else if (key == ARROW_RIGHT || key == ARROW_DOWN)
+	{
+		direction = 1;
+	}
+	else if (key == ARROW_LEFT || key == ARROW_UP)
+	{
+		direction = -1;
+	}
+	else
+	{
+		last_match = -1;
+		direction = 1;
+	}
+
+	if (last_match == -1)
+	{
+		direction = 1;
+	}
+	int current = last_match;
+	int i;
+	for (i = 0; i < E.numrows; i++)
+	{
+		current += direction;
+		if (current == -1)
+		{
+			current = E.numrows -1;
+		}
+		else if (current == E.numrows)
+		{
+			current = 0;
+		}
+
+		erow *row = &E.row[current];
+		char *match = strstr(row->render, query);
+		if (match)
+		{
+			last_match = current;
+			E.cy = current;
+			E.cx = editorRowRxToCx(row, match - row->render);
+			E.rowoff = E.numrows;
+			break;
+		}
+	}
+}
+
+void editorFind()
+{
+	int saved_cx = E.cx;
+	int saved_cy = E.cy;
+	int saved_coloff = E.coloff;
+	int saved_rowoff = E.rowoff;
+
+	char *query = editorPrompt("Search: %s (Use ESC/Arrows/Enter)",
+			editorFindCallback);
+
+	if (query)
+	{
+		free(query);
+	}
+	else
+	{
+		E.cx = saved_cx;
+		E.cy = saved_cy;
+		E.coloff = saved_coloff;
+		E.rowoff = saved_rowoff;
+	}
+}
+
 /*** append buffer ***/
 
 struct abuf {
@@ -735,7 +837,7 @@ void editorSetStatusMessage(const char *fmt, ...)
 
 /*** input ***/
 
-char *editorPrompt(char *prompt)
+char *editorPrompt(char *prompt, void (*callback)(char *, int))
 {
 	size_t bufsize = 128;
 	char *buf = malloc(bufsize);
@@ -759,6 +861,10 @@ char *editorPrompt(char *prompt)
 		else if (c == '\x1b')
 		{
 			editorSetStatusMessage("");
+			if (callback)
+			{
+				callback(buf, c);
+			}
 			free(buf);
 			return NULL;
 		}
@@ -767,6 +873,10 @@ char *editorPrompt(char *prompt)
 			if (buflen != 0)
 			{
 				editorSetStatusMessage("");
+				if (callback)
+				{
+					callback(buf, c);
+				}
 				return buf;
 			}
 		}
@@ -780,6 +890,11 @@ char *editorPrompt(char *prompt)
 			buf[buflen++] = c;
 			buf[buflen] = '\0';
 		}
+
+		if (callback)
+		{
+			callback(buf, c);
+		}
 	}
 }
 
@@ -876,6 +991,10 @@ void editorProcessKeypress()
 			}
 		break;
 
+		case CTRL_KEY('f'):
+			editorFind();
+		break;
+
 		case BACKSPACE:
 		case CTRL_KEY('h'):
 		case DEL_KEY:
@@ -962,7 +1081,8 @@ int main(int argc, char *argv[])
 		editorOpen(argv[1]);
 	}
 
-	editorSetStatusMessage("HELP: Ctrl-S = save | Ctrl-Q = quit");
+	editorSetStatusMessage(
+			"HELP: Ctrl-S = save | Ctrl-Q = quit | Ctrl-F = find");
 
 	while (1)
 	{