Merge pull request #1717 from jclulow/illumos-cfmakeraw

fix cfmakeraw() for illumos and Solaris

Author: JohnTitor

src/unix/solarish/compat.rs

@@ -4,8 +4,7 @@
 use unix::solarish::*;
 
 pub unsafe fn cfmakeraw(termios: *mut ::termios) {
-    let mut t = *termios as ::termios;
-    t.c_iflag &= !(IMAXBEL
+    (*termios).c_iflag &= !(IMAXBEL
         | IGNBRK
         | BRKINT
         | PARMRK
@@ -14,10 +13,26 @@ pub unsafe fn cfmakeraw(termios: *mut ::termios) {
         | IGNCR
         | ICRNL
         | IXON);
-    t.c_oflag &= !OPOST;
-    t.c_lflag &= !(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
-    t.c_cflag &= !(CSIZE | PARENB);
-    t.c_cflag |= CS8;
+    (*termios).c_oflag &= !OPOST;
+    (*termios).c_lflag &= !(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+    (*termios).c_cflag &= !(CSIZE | PARENB);
+    (*termios).c_cflag |= CS8;
+
+    // By default, most software expects a pending read to block until at
+    // least one byte becomes available.  As per termio(7I), this requires
+    // setting the MIN and TIME parameters appropriately.
+    //
+    // As a somewhat unfortunate artefact of history, the MIN and TIME slots
+    // in the control character array overlap with the EOF and EOL slots used
+    // for canonical mode processing.  Because the EOF character needs to be
+    // the ASCII EOT value (aka Control-D), it has the byte value 4.  When
+    // switching to raw mode, this is interpreted as a MIN value of 4; i.e.,
+    // reads will block until at least four bytes have been input.
+    //
+    // Other platforms with a distinct MIN slot like Linux and FreeBSD appear
+    // to default to a MIN value of 1, so we'll force that value here:
+    (*termios).c_cc[VMIN] = 1;
+    (*termios).c_cc[VTIME] = 0;
 }
 
 pub unsafe fn cfsetspeed(