integrate interactive command editing

1 files changed, 65 insertions, 0 deletions

diff --git a/shed.c b/shed.c
new file mode 100644
index 0000000..a0cc554
--- /dev/null
+++ b/shed.c
@@ -0,0 +1,65 @@
+#define _POSIX_C_SOURCE 200809L
+#include <stdlib.h>
+#include <string.h>
+#include <termios.h>
+#include <unistd.h>
+#include "shed.h"
+
+/*
+ * BIG FAT TODO: DEAL WITH MULTIBYTE CHARACTERS CORRECTLY
+ */
+
+struct shed *shed(struct shed *e)
+{
+	if (e == NULL) {
+		e = calloc(1, sizeof(*e));
+		if (e == NULL) {
+			return NULL;
+		}
+	}
+
+	/* TODO: head/tail/history */
+	if (e->cur == NULL) {
+		e->cur = calloc(1, sizeof(*e->cur));
+		if (e->cur == NULL) {
+			return e;
+		}
+		e->handle = shed_handle_non_vi;
+	}
+
+	memset(e->cur, '\0', sizeof(*e->cur));
+
+	struct termios original_tio;
+	if (tcgetattr(STDIN_FILENO, &original_tio) != 0) {
+		e->cur = NULL;
+		return e;
+	}
+
+	struct termios tio = original_tio;
+	tio.c_iflag &= ~BRKINT;
+	tio.c_lflag &= ~ECHO;
+	tio.c_lflag &= ~IEXTEN;
+	tio.c_lflag &= ~ICANON;
+	tio.c_lflag &= ~ISIG;
+	tcsetattr(STDIN_FILENO, TCSADRAIN, &tio);
+
+	if (e->prompt == NULL) {
+		e->prompt = getenv("PS1");
+		if (e->prompt == NULL) {
+			e->prompt = "$ ";
+		}
+	}
+	write(STDOUT_FILENO, e->prompt, strlen(e->prompt));
+
+	char c;
+	do {
+		if (read(STDIN_FILENO, &c, 1) == -1) {
+			//b.nread = -1;
+			/* TODO: signal failure */
+			break;
+		}
+	} while (e->handle(e, &tio, c));
+
+	tcsetattr(STDIN_FILENO, TCSADRAIN, &original_tio);
+	return e;
+}