term: the new switchery to later enable term_type=win32

git-svn-id: svn://scm.orgis.org/mpg123/trunk@5082 35dc7657-300d-0410-a2e5-dc2837fedb53

src/term_posix.c

@@ -0,0 +1,199 @@
+/*
+	term_posix: POSIX-specifc terminal functionality
+
+	HAVE_TERMIOS is a prerequisite.
+
+	copyright 2008-2022 by the mpg123 project - free software under the terms of the LGPL 2.1
+	see COPYING and AUTHORS files in distribution or http://mpg123.org
+	initially written by Thomas Orgis
+*/
+
+#include "config.h"
+
+#include "compat.h"
+
+#ifndef HAVE_TERMIOS
+#error "No TERMIOS? Here?"
+#endif
+
+// for param struct
+#include "mpg123app.h"
+
+#include <termios.h>
+#include <sys/ioctl.h>
+
+#include "terms.h"
+
+#include "debug.h"
+
+static int term_is_fun = -1;
+// This now always refers to a ;freshly opened terminal descriptor (e.g. /dev/tty).
+// Printouts to stderr are independent of this.
+static int term_fd = -1;
+static struct termios old_tio;
+
+/* Buffered key from a signal or whatnot.
+   We ignore the null character... */
+static char prekey = 0;
+
+int term_have_fun(int fd, int want_visuals)
+{
+	if(term_is_fun > -1)
+		return term_is_fun;
+	else
+		term_is_fun = 0;
+	if(term_width(fd) > 0 && want_visuals)
+	{
+		/* Only play with non-dumb terminals. */
+		char *tname = compat_getenv("TERM");
+		if(tname)
+		{
+			if(strcmp(tname, "") && strcmp(tname, "dumb"))
+				term_is_fun = 1;
+			free(tname);
+		}
+	}
+	return term_is_fun;
+}
+
+/* Also serves as a way to detect if we have an interactive terminal. */
+int term_width(int fd)
+{
+	struct winsize geometry;
+	geometry.ws_col = 0;
+	if(ioctl(fd, TIOCGWINSZ, &geometry) >= 0)
+		return (int)geometry.ws_col;
+	return -1;
+}
+
+static int term_setup_detail(struct termios *pattern);
+
+static void term_sigcont(int sig)
+{
+	if(term_setup_detail(&old_tio) < 0)
+	{
+		debug("Can't set terminal attributes");
+		return;
+	}
+}
+
+static void term_sigusr(int sig)
+{
+	switch(sig)
+	{
+		case SIGUSR1: prekey=*param.term_usr1; break;
+		case SIGUSR2: prekey=*param.term_usr2; break;
+	}
+}
+
+/* This must call only functions safe inside a signal handler. */
+static int term_setup_detail(struct termios *pattern)
+{
+	mdebug("setup on fd %d", term_fd);
+
+	/* One might want to use sigaction instead. */
+	signal(SIGCONT, term_sigcont);
+	signal(SIGUSR1, term_sigusr);
+	signal(SIGUSR2, term_sigusr);
+	struct termios tio = *pattern;
+	tio.c_lflag &= ~(ICANON|ECHO); 
+	tio.c_cc[VMIN] = 1;
+	tio.c_cc[VTIME] = 0;
+#ifdef __OS2__
+	// Do not care for the error until OS/2 is known to work.
+	tcsetattr(term_fd,TCSANOW,&tio);
+	return 0;
+#else
+	return tcsetattr(term_fd,TCSANOW,&tio);
+#endif
+}
+
+int term_setup(void)
+{
+	if(term_fd < 0)
+	{
+		const char *term_name;
+#ifdef HAVE_CTERMID
+		term_name = ctermid(NULL);
+#else
+		term_name = "/dev/tty";
+#endif
+		if(term_name)
+			mdebug("accessing terminal for control via %s", term_name);
+		else
+		{
+			error("no controlling terminal");
+			return -1;
+		}
+		term_fd = open(term_name, O_RDONLY);
+		if(term_fd < 0)
+		{
+			merror("failed to open terminal: %s", strerror(errno));
+			return -1;
+		}
+	}
+
+	if(tcgetattr(term_fd, &old_tio) < 0)
+	{
+		// For now, this always fails on OS/2, but they might fix things.
+		// So just try to move on.
+#ifndef __OS2__
+		merror("failed to get terminal attributes: %s", strerror(errno));
+		return -1;
+#endif
+	}
+
+	errno = 0;
+	if(term_setup_detail(&old_tio) < 0)
+	{
+		close(term_fd);
+		term_fd = -1;
+		if(errno)
+			merror("failure setting terminal attributes: %s", strerror(errno));
+		else
+			error("failure setting terminal attributes");
+		return -1;
+	}
+	return 0;
+}
+
+/* Get the next pressed key, if any.
+   Returns 1 when there is a key, 0 if not. */
+int term_get_key(int do_delay, char *val)
+{
+	fd_set r;
+	struct timeval t;
+
+	/* Shortcut: If some other means sent a key, use it. */
+	if(prekey)
+	{
+		debug1("Got prekey: %c\n", prekey);
+		*val = prekey;
+		prekey = 0;
+		return 1;
+	}
+
+	t.tv_sec=0;
+	t.tv_usec=(do_delay) ? 10*1000 : 0;
+
+	FD_ZERO(&r);
+	FD_SET(term_fd,&r);
+	if(select(term_fd+1,&r,NULL,NULL,&t) > 0 && FD_ISSET(term_fd,&r))
+	{
+		if(read(term_fd,val,1) <= 0)
+		return 0; /* Well, we couldn't read the key, so there is none. */
+		else
+		return 1;
+	}
+	else return 0;
+}
+
+void term_restore(void)
+{
+	debug("reset attrbutes");
+	tcsetattr(term_fd,TCSAFLUSH,&old_tio);
+
+	if(term_fd > -1)
+		close(term_fd);
+	term_fd = -1;
+}