links old version of cf{g,s}et{i,o}speed for glibc

libc-test/build.rs

@@ -4784,6 +4784,30 @@ fn test_linux(target: &str) {
         _ => false,
     });
 
+    if gnu {
+        // old constants, so tests fail if glibc is too new
+        cfg.skip_const(|s| {
+            [
+                "B50", "B75", "B110", "B134", "B150", "B200", "B300", "B600", "B1200", "B1800",
+                "B2400", "B4800", "B9600", "B19200", "B38400", "EXTA", "EXTB", "B57600", "B115200",
+                "B230400", "B460800", "B500000", "B576000", "B921600", "B1000000", "B1152000",
+                "B1500000", "B2000000", "B2500000", "B3000000", "B3500000", "B4000000",
+            ]
+            .contains(&s.ident())
+        });
+        // old symbols, so tests fail if glibc is too new
+        cfg.skip_fn_ptrcheck(|s| {
+            [
+                "cfgetispeed",
+                "cfgetospeed",
+                "cfsetispeed",
+                "cfsetospeed",
+                "cfsetspeed",
+            ]
+            .contains(&s)
+        });
+    }
+
     ctest::generate_test(&mut cfg, "../src/lib.rs", "ctest_output.rs").unwrap();
 
     if !l4re {

libc-test/tests/linux_gnu_baud.rs

@@ -0,0 +1,33 @@
+#[cfg(all(target_os = "linux", target_env = "gnu"))]
+#[test]
+fn baud() {
+    use libc::*;
+    let controller_fd = unsafe { posix_openpt(O_RDWR | O_NOCTTY) };
+    assert!(controller_fd >= 0);
+    unsafe {
+        grantpt(controller_fd);
+        unlockpt(controller_fd);
+    }
+    let mut buffer = [0; 256];
+    let ret = unsafe { ptsname_r(controller_fd, buffer.as_mut_ptr(), 256) };
+    assert!(ret >= 0);
+    let terminal_fd = unsafe { open(buffer.as_ptr(), O_RDWR | O_NOCTTY) };
+    assert!(terminal_fd >= 0);
+    let mut tio: termios = unsafe { std::mem::zeroed() };
+    let ret = unsafe { tcgetattr(terminal_fd, &mut tio) };
+    assert!(ret >= 0);
+    assert_eq!(unsafe { cfgetispeed(&tio) }, B38400);
+    assert_eq!(unsafe { cfgetospeed(&tio) }, B38400);
+    let ret = unsafe { cfsetspeed(&mut tio, B1000000) };
+    assert!(ret >= 0);
+    assert_eq!(unsafe { cfgetispeed(&tio) }, B1000000);
+    assert_eq!(unsafe { cfgetospeed(&tio) }, B1000000);
+    let ret = unsafe { cfsetispeed(&mut tio, B9600) };
+    assert!(ret >= 0);
+    assert_eq!(unsafe { cfgetispeed(&tio) }, B9600);
+    assert!(matches!(unsafe { cfgetospeed(&tio) }, B9600 | B1000000));
+    let ret = unsafe { cfsetospeed(&mut tio, B19200) };
+    assert!(ret >= 0);
+    assert!(matches!(unsafe { cfgetispeed(&tio) }, B9600 | B19200));
+    assert_eq!(unsafe { cfgetospeed(&tio) }, B19200);
+}