1 files changed, 152 insertions, 0 deletions
diff --git a/lib/ttyutils.c b/lib/ttyutils.c
new file mode 100644
index 0000000..7064565
--- /dev/null
+++ b/lib/ttyutils.c
@@ -0,0 +1,152 @@
+/*
+ * No copyright is claimed.  This code is in the public domain; do with
+ * it what you wish.
+ *
+ * Written by Karel Zak <kzak@redhat.com>
+ */
+#include <ctype.h>
+#include <unistd.h>
+
+#include "c.h"
+#include "ttyutils.h"
+
+
+static int get_env_int(const char *name)
+{
+	const char *cp = getenv(name);
+
+	if (cp) {
+		char *end = NULL;
+		long x;
+
+		errno = 0;
+		x = strtol(cp, &end, 10);
+
+		if (errno == 0 && end && *end == '\0' && end > cp &&
+		    x > 0 && x <= INT_MAX)
+			return x;
+	}
+
+	return -1;
+}
+
+int get_terminal_dimension(int *cols, int *lines)
+{
+	int c = 0, l = 0;
+
+#if defined(TIOCGWINSZ)
+	struct winsize	w_win;
+	if (ioctl (STDOUT_FILENO, TIOCGWINSZ, &w_win) == 0) {
+		c = w_win.ws_col;
+		l = w_win.ws_row;
+	}
+#elif defined(TIOCGSIZE)
+	struct ttysize	t_win;
+	if (ioctl (STDOUT_FILENO, TIOCGSIZE, &t_win) == 0) {
+		c = t_win.ts_cols;
+		l = t_win.ts_lines;
+	}
+#endif
+	if (cols) {
+		if (c <= 0)
+			c = get_env_int("COLUMNS");
+		*cols = c;
+	}
+	if (lines) {
+		if (l <= 0)
+			l = get_env_int("LINES");
+		*lines = l;
+	}
+	return 0;
+}
+
+int get_terminal_width(int default_width)
+{
+	int width = 0;
+
+	get_terminal_dimension(&width, NULL);
+
+	return width > 0 ? width : default_width;
+}
+
+int get_terminal_stdfd(void)
+{
+	if (isatty(STDIN_FILENO))
+		return STDIN_FILENO;
+	if (isatty(STDOUT_FILENO))
+		return STDOUT_FILENO;
+	if (isatty(STDERR_FILENO))
+		return STDERR_FILENO;
+
+	return -EINVAL;
+}
+
+int get_terminal_name(const char **path,
+		      const char **name,
+		      const char **number)
+{
+	const char *tty;
+	const char *p;
+	int fd;
+
+
+	if (name)
+		*name = NULL;
+	if (path)
+		*path = NULL;
+	if (number)
+		*number = NULL;
+
+	fd = get_terminal_stdfd();
+	if (fd < 0)
+		return fd;	/* error */
+
+	tty = ttyname(fd);
+	if (!tty)
+		return -1;
+
+	if (path)
+		*path = tty;
+	if (name || number)
+		tty = strncmp(tty, "/dev/", 5) == 0 ? tty + 5 : tty;
+	if (name)
+		*name = tty;
+	if (number) {
+		for (p = tty; p && *p; p++) {
+			if (isdigit(*p)) {
+				*number = p;
+				break;
+			}
+		}
+	}
+	return 0;
+}
+
+int get_terminal_type(const char **type)
+{
+	*type = getenv("TERM");
+	if (*type)
+		return -EINVAL;
+	return 0;
+}
+
+#ifdef TEST_PROGRAM_TTYUTILS
+# include <stdlib.h>
+int main(void)
+{
+	const char *path, *name, *num;
+	int c, l;
+
+	if (get_terminal_name(&path, &name, &num) == 0) {
+		fprintf(stderr, "tty path:   %s\n", path);
+		fprintf(stderr, "tty name:   %s\n", name);
+		fprintf(stderr, "tty number: %s\n", num);
+	}
+	get_terminal_dimension(&c, &l);
+	fprintf(stderr,         "tty cols:   %d\n", c);
+	fprintf(stderr,         "tty lines:  %d\n", l);
+
+
+	return EXIT_SUCCESS;
+}
+#endif /* TEST_PROGRAM_TTYUTILS */