Added mg from an OpenBSD mirror site. Many thanks to the OpenBSD team and the mg...

[pd_readline] / mg / ttyio.c

diff --git a/mg/ttyio.c b/mg/ttyio.c
new file mode 100644 (file)
index 0000000..228a370
--- /dev/null
+++ b/mg/ttyio.c
@@ -0,0 +1,225 @@
+/*     $OpenBSD: ttyio.c,v 1.32 2008/02/05 12:53:38 reyk Exp $ */
+
+/* This file is in the public domain. */
+
+/*
+ * POSIX terminal I/O.
+ *
+ * The functions in this file negotiate with the operating system for
+ * keyboard characters, and write characters to the display in a barely
+ * buffered fashion.
+ */
+#include "def.h"
+
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <termios.h>
+#include <term.h>
+
+#define NOBUF  512                     /* Output buffer size. */
+
+#ifndef TCSASOFT
+#define TCSASOFT       0
+#endif
+
+int    ttstarted;
+char   obuf[NOBUF];                    /* Output buffer. */
+size_t nobuf;                          /* Buffer count. */
+struct termios oldtty;                 /* POSIX tty settings. */
+struct termios newtty;
+int    nrow;                           /* Terminal size, rows. */
+int    ncol;                           /* Terminal size, columns. */
+
+/*
+ * This function gets called once, to set up the terminal.
+ * On systems w/o TCSASOFT we turn off off flow control,
+ * which isn't really the right thing to do.
+ */
+void
+ttopen(void)
+{
+       if (!isatty(STDIN_FILENO) || !isatty(STDOUT_FILENO))
+               panic("standard input and output must be a terminal");
+
+       if (ttraw() == FALSE)
+               panic("aborting due to terminal initialize failure");
+}
+
+/*
+ * This function sets the terminal to RAW mode, as defined for the current
+ * shell.  This is called both by ttopen() above and by spawncli() to
+ * get the current terminal settings and then change them to what
+ * mg expects. Thus, tty changes done while spawncli() is in effect
+ * will be reflected in mg.
+ */
+int
+ttraw(void)
+{
+       if (tcgetattr(0, &oldtty) < 0) {
+               ewprintf("ttopen can't get terminal attributes");
+               return (FALSE);
+       }
+       (void)memcpy(&newtty, &oldtty, sizeof(newtty));
+       /* Set terminal to 'raw' mode and ignore a 'break' */
+       newtty.c_cc[VMIN] = 1;
+       newtty.c_cc[VTIME] = 0;
+       newtty.c_iflag |= IGNBRK;
+       newtty.c_iflag &= ~(BRKINT | PARMRK | INLCR | IGNCR | ICRNL | IXON);
+       newtty.c_oflag &= ~OPOST;
+       newtty.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+
+#if !TCSASOFT
+       /*
+        * If we don't have TCSASOFT, force terminal to
+        * 8 bits, no parity.
+        */
+       newtty.c_iflag &= ~ISTRIP;
+       newtty.c_cflag &= ~(CSIZE | PARENB);
+       newtty.c_cflag |= CS8;
+#endif
+       if (tcsetattr(0, TCSASOFT | TCSADRAIN, &newtty) < 0) {
+               ewprintf("ttopen can't tcsetattr");
+               return (FALSE);
+       }
+       ttstarted = 1;
+
+       return (TRUE);
+}
+
+/*
+ * This function gets called just before we go back home to the shell.
+ * Put all of the terminal parameters back.
+ * Under UN*X this just calls ttcooked(), but the ttclose() hook is in
+ * because vttidy() in display.c expects it for portability reasons.
+ */
+void
+ttclose(void)
+{
+       if (ttstarted) {
+               if (ttcooked() == FALSE)
+                       panic("");      /* ttcooked() already printf'd */
+               ttstarted = 0;
+       }
+}
+
+/*
+ * This function restores all terminal settings to their default values,
+ * in anticipation of exiting or suspending the editor.
+ */
+int
+ttcooked(void)
+{
+       ttflush();
+       if (tcsetattr(0, TCSASOFT | TCSADRAIN, &oldtty) < 0) {
+               ewprintf("ttclose can't tcsetattr");
+               return (FALSE);
+       }
+       return (TRUE);
+}
+
+/*
+ * Write character to the display.  Characters are buffered up,
+ * to make things a little bit more efficient.
+ */
+int
+ttputc(int c)
+{
+       if (nobuf >= NOBUF)
+               ttflush();
+       obuf[nobuf++] = c;
+       return (c);
+}
+
+/*
+ * Flush output.
+ */
+void
+ttflush(void)
+{
+       ssize_t  written;
+       char    *buf = obuf;
+
+       if (nobuf == 0)
+               return;
+
+       while ((written = write(fileno(stdout), buf, nobuf)) != nobuf) {
+               if (written == -1) {
+                       if (errno == EINTR)
+                               continue;
+                       panic("ttflush write failed");
+               }
+               buf += written;
+               nobuf -= written;
+       }
+       nobuf = 0;
+}
+
+/*
+ * Read character from terminal. All 8 bits are returned, so that you
+ * can use a multi-national terminal.
+ */
+int
+ttgetc(void)
+{
+       char    c;
+       ssize_t ret;
+
+       do {
+               ret = read(STDIN_FILENO, &c, 1);
+               if (ret == -1 && errno == EINTR) {
+                       if (winch_flag) {
+                               redraw(0, 0);
+                               winch_flag = 0;
+                       }
+               } else if (ret == 1)
+                       break;
+       } while (1);
+       return ((int) c) & 0xFF;
+}
+
+/*
+ * Returns TRUE if there are characters waiting to be read.
+ */
+int
+charswaiting(void)
+{
+       int     x;
+
+       return ((ioctl(0, FIONREAD, &x) < 0) ? 0 : x);
+}
+
+/*
+ * panic - just exit, as quickly as we can.
+ */
+void
+panic(char *s)
+{
+       ttclose();
+       (void) fputs("panic: ", stderr);
+       (void) fputs(s, stderr);
+       (void) fputc('\n', stderr);
+       exit(1);
+}
+
+/*
+ * This function returns FALSE if any characters have showed up on the
+ * tty before 'msec' milliseconds.
+ */
+int
+ttwait(int msec)
+{
+       fd_set          readfds;
+       struct timeval  tmout;
+
+       FD_ZERO(&readfds);
+       FD_SET(0, &readfds);
+
+       tmout.tv_sec = msec/1000;
+       tmout.tv_usec = msec - tmout.tv_sec * 1000;
+
+       if ((select(1, &readfds, NULL, NULL, &tmout)) == 0)
+               return (TRUE);
+       return (FALSE);
+}