1 files changed, 140 insertions, 0 deletions
diff --git a/src/reader.cpp b/src/reader.cpp
new file mode 100644
index 0000000..508205d
--- /dev/null
+++ b/src/reader.cpp
@@ -0,0 +1,140 @@
+#include "reader.h"
+#include <csignal>
+
+void die(const char *s) {
+	write(STDOUT_FILENO, "\x1b[2J", 4);
+	write(STDOUT_FILENO, "\x1b[H", 3);
+
+	perror(s);
+	fprintf(stderr, "[exit]: die(s) invoked, exiting..\n");
+	exit(1);
+}
+
+static editor_cfg *g_cfg = nullptr;
+
+void disable_raw_atexit() {
+	if (g_cfg) {
+		tcsetattr(STDIN_FILENO, TCSAFLUSH, &(g_cfg->termios_inst));
+	}
+}
+
+void handle_signal(int sig) {
+	disable_raw_atexit();
+	_exit(128 + sig);
+}
+
+void disable_raw(editor_cfg *cfg) {
+	if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &(cfg->termios_inst)))
+		die("tcsetattr");
+}
+
+void enable_raw(editor_cfg *cfg) {
+	if (tcgetattr(STDIN_FILENO, &(cfg->termios_inst)) == -1)
+		die("tcgetattr");
+
+	g_cfg = cfg;
+
+	std::atexit(disable_raw_atexit);
+
+	std::signal(SIGINT, handle_signal);
+	std::signal(SIGTERM, handle_signal);
+	std::signal(SIGQUIT, handle_signal);
+
+	struct termios raw = cfg->termios_inst;
+	raw.c_iflag &= ~(IXON | ICRNL | BRKINT | INPCK | ISTRIP);
+	raw.c_oflag &= ~(OPOST);
+	raw.c_lflag &=
+		~(ECHO | ICANON | IEXTEN); // disables several keybinds in terminal
+
+	raw.c_cc[VMIN] = 0;
+	raw.c_cc[VTIME] = 1;
+
+	if (tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw) == -1)
+		die("tcsetattr");
+}
+
+char editor_readkey() {
+	int nread;
+	char c;
+
+	while ((nread = read(STDIN_FILENO, &c, 1)) != 1) {
+		if (nread == -1 && errno != EAGAIN)
+			die("read");
+	}
+	return c;
+}
+
+int get_cursor_pos(int *rows, int *cols) {
+	char buff[32];
+	unsigned int i = 0;
+
+	if (write(STDOUT_FILENO, "\x1b[6n", 4) != 4) {
+		return -1;
+	}
+	while (i < sizeof(buff) - 1) {
+		if (read(STDIN_FILENO, &buff[i], 1) != 1)
+			break;
+		if (buff[i] == 'R')
+			break;
+		i++;
+	}
+	buff[i] = '\0';
+
+	if (buff[0] != '\x1b' || buff[1] != '[')
+		return -1;
+	if (sscanf(&buff[2], "%d;%d", rows, cols) != 2)
+		return -1;
+	return 0;
+}
+
+int get_window_size(int *rows, int *cols) {
+	struct winsize w_size;
+
+	if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &w_size) == -1 ||
+			w_size.ws_col == 0) {
+		if (write(STDOUT_FILENO, "\x1b[999C\x1b[999B", 12) != 12)
+			return -1;
+		return get_cursor_pos(rows, cols);
+	}
+
+	*rows = w_size.ws_row;
+	*cols = w_size.ws_col;
+
+	return 0;
+}
+
+void editor_refresh_scrn(editor_cfg *cfg) {
+	append_buffer::instance().append("\x1b[2J", 4);
+	char buff[32];
+	memset(buff, 0, sizeof(buff));
+
+	snprintf(buff, sizeof(buff), "\x1b[%d;%dH", cfg->screenrows / 2, cfg->screencols / 2);
+
+	append_buffer::instance().append(buff, strlen(buff));
+	append_buffer::instance().write_output();
+	append_buffer::instance().remove();
+}
+
+size_t split(const std::string &txt, std::vector<std::string> &strings, const std::string &delims) {
+	size_t initial_pos = txt.find_first_not_of(delims, 0);
+	size_t pos = txt.find_first_of(delims, initial_pos);
+
+	while (initial_pos != std::string::npos) {
+		strings.push_back(txt.substr(initial_pos, pos - initial_pos));
+		initial_pos = txt.find_first_not_of(delims, pos);
+		pos = txt.find_first_of(delims, initial_pos);
+	}
+	return strings.size();
+}
+
+void init_editor(editor_cfg *cfg) {
+	if (get_window_size(&(cfg->screenrows), &(cfg->screencols)) == -1)
+		die("get_window_size");
+}
+
+int is_number(char *strnum) {
+	std::string str = strnum;
+	std::string::const_iterator it = str.begin();
+	while (it != str.end() && std::isdigit(*it)) ++it;
+	return !str.empty() && it == str.end();
+}