cli interpreter

cli_interpreter.c

#define POSINC(__x) (((__x) < (CLI_CMD_BUFFER_SIZE - 1)) ? (__x + 1) : (__x))
#define POSDEC(__x) ((__x) ? ((__x) - 1) : 0)

#define KEY_CODE_BACKSPACE 0x7f
#define KEY_CODE_DELETE 0x1b
#define KEY_CODE_ENTER 0x0a

#define CLI_IO_INPUT(__data) \
	linux_getc(__data)
	

#define CLI_IO_OUTPUT(__data, __len) \
	linux_putc(__data, __len)

static void _cli_prompt(t_cli_ctx *a_ctx __attribute__((unused)), unsigned char nl) {
	if (nl) CLI_IO_OUTPUT("\r\n", 2);
	CLI_IO_OUTPUT("#> ", 3);
}

void cli_read(t_cli_ctx *a_ctx) {

	unsigned char i = 0x00;

	// if no character available - then exit
	if (!CLI_IO_INPUT(&i)) return;

	/// char by char matching
	switch(i) {
		case KEY_CODE_BACKSPACE: // backspace
		case KEY_CODE_DELETE: // del
			if (a_ctx->cpos) {
				a_ctx->cmd[a_ctx->cpos--] = '\0';
				CLI_IO_OUTPUT("\b \b", 3);
			}
			break;


		case KEY_CODE_ENTER: // new line
			a_ctx->cmd[POSINC(a_ctx->cpos)] = '\0';
			CLI_IO_OUTPUT("\r\n", 2);

			a_ctx->cpos = 0;
			memset(a_ctx->cmd, 0x00, CLI_CMD_BUFFER_SIZE);
			_cli_prompt(a_ctx, 1);
			break;

		default:
			/* echo */
			if (a_ctx->cpos < (CLI_CMD_BUFFER_SIZE - 1) && isprint(i)) {
				a_ctx->cmd[a_ctx->cpos++] = i;
				CLI_IO_OUTPUT(&i, 1);
			}
			break;
	}
}