linux/termios: test the kernel-side termios canonicalization

Verify that the kernel side of the termios interface gets the various
speed fields set according to our current canonicalization policy.

[ v2.1: fix formatting - Adhemerval Netto ]
[ v4: fix typo in patch description - Dan Horák ]

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> (v2.1)
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
This commit is contained in:
H. Peter Anvin 2025-11-18 10:21:18 -08:00 committed by H.J. Lu
parent cdb0e9dc70
commit 40a751b004
1 changed files with 58 additions and 3 deletions

View File

@ -38,6 +38,8 @@
#include <support/test-driver.h>
#include <support/tty.h>
#include <k_termios.h> /* Definitions for the raw ioctl interface */
/* Evaluate an expression and make sure errno did not get set; return
the value of the expression */
#define CHECKERR(expr) \
@ -226,13 +228,66 @@ static void check_speeds_cf (const struct termios *tio_p,
CHECKERR (cfgetibaud (tio_p)), 'i');
}
/* Use this after tc[gs]etattr () */
/* Access the raw kernel interface and verify that the result is
canonicalized properly; this should be run after tcsetattr (). */
static void
check_speeds_kernel (int fd, speed_t ospeed, speed_t ispeed)
{
struct termios2 k_termios;
tcflag_t expect_cbaud = speed_to_cbaud (ospeed);
tcflag_t expect_cibaud;
if (!ispeed)
ispeed = ospeed;
/* If ospeed == ispeed, tcsetattr() should set the kernel CIBAUD to 0,
for compatibility with programs that use the direct ioctl interface
but fail to account for CIBAUD. c_ispeed should still be correct. */
if (ospeed == ispeed)
expect_cibaud = 0;
else
expect_cibaud = speed_to_cbaud (ispeed);
memset (&k_termios, 0xed, sizeof k_termios); /* Fill with nonsense */
CHECKZERO (ioctl(fd, TCGETS2, &k_termios));
tcflag_t k_cbaud = k_termios.c_cflag & CBAUD;
tcflag_t k_cibaud = (k_termios.c_cflag >> IBSHIFT) & CBAUD;
if (k_termios.c_ospeed != ospeed)
FAIL ("opeed %u ispeed %u: kernel c_ospeed = %u, expected %u",
ospeed, ispeed,
k_termios.c_ospeed, ospeed);
if (k_cbaud != expect_cbaud)
FAIL ("ospeed %u ispeed %u: kernel CBAUD = %s (%06o), expected %s (%06o)",
ospeed, ispeed,
cbaud_name (k_cbaud), k_cbaud,
cbaud_name (expect_cbaud), expect_cbaud);
if (k_termios.c_ispeed != ispeed)
FAIL ("ospeed %u ispeed %u: kernel c_ispeed == %u, expected %u",
ospeed, ispeed,
k_termios.c_ispeed, ispeed);
if (k_cibaud != expect_cibaud)
FAIL ("ospeed %u ispeed %u: kernel CIBAUD = %s (%06o), expected %s (%06o)",
ospeed, ispeed,
cbaud_name (k_cibaud), k_cibaud,
cbaud_name (expect_cibaud), expect_cibaud);
}
/* Use this after tcsetattr () */
static void check_speeds_tc (int fd, speed_t ospeed, speed_t ispeed)
{
struct termios tio;
if (!ispeed)
ispeed = ospeed;
CHECKZERO (tcgetattr (fd, &tio));
check_speeds_cf (&tio, ospeed, ispeed ? ispeed : ospeed);
check_speeds_cf (&tio, ospeed, ispeed);
check_speeds_kernel (fd, ospeed, ispeed);
}
/* For search and replace convenience */
@ -250,7 +305,7 @@ set_speeds (int fd, speed_t ospeed, speed_t ispeed)
CHECKZERO (cfsetispeed (&tio, ispeed));
check_speeds_cf (&tio, ospeed, ispeed);
CHECKZERO (tcsetattr (fd, TCSANOW, &tio));
check_speeds_tc (fd, ospeed, ispeed ? ispeed : ospeed);
check_speeds_tc (fd, ospeed, ispeed);
}
/* Actual tests */