From: Simon Glass <sjg@chromium.org> Add a serial_is_tty() function that determines if the serial console is connected to a terminal. For sandbox, this uses os_isatty() to check stdin, except for cooked mode, where we don't want to assume anything about the terminal. For other platforms, it always returns true. Co-developed-by: Claude <noreply@anthropic.com> Signed-off-by: Simon Glass <sjg@chromium.org> --- (no changes since v1) arch/sandbox/cpu/os.c | 5 +++++ arch/sandbox/cpu/start.c | 4 ++++ arch/sandbox/cpu/state.c | 7 +++++++ arch/sandbox/include/asm/state.h | 8 ++++++++ include/os.h | 8 ++++++++ include/serial.h | 21 +++++++++++++++++++++ 6 files changed, 53 insertions(+) diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c index c19f859d4e0..101d695a556 100644 --- a/arch/sandbox/cpu/os.c +++ b/arch/sandbox/cpu/os.c @@ -142,6 +142,11 @@ int os_close(int fd) return -1; } +int os_isatty(int fd) +{ + return isatty(fd); +} + int os_unlink(const char *pathname) { return unlink(pathname); diff --git a/arch/sandbox/cpu/start.c b/arch/sandbox/cpu/start.c index e4e4932c183..02d16bfe930 100644 --- a/arch/sandbox/cpu/start.c +++ b/arch/sandbox/cpu/start.c @@ -613,6 +613,10 @@ int sandbox_main(int argc, char *argv[]) if (os_parse_args(state, argc, argv)) return 1; + /* Detect if serial console is connected to a terminal */ + state->serial_is_tty = os_isatty(1) && + state->term_raw != STATE_TERM_COOKED; + if (state->ram_buf_fname) { ret = os_read_ram_buf(state->ram_buf_fname); if (ret) { diff --git a/arch/sandbox/cpu/state.c b/arch/sandbox/cpu/state.c index 949ca42de94..d883cf2132a 100644 --- a/arch/sandbox/cpu/state.c +++ b/arch/sandbox/cpu/state.c @@ -476,6 +476,13 @@ bool sandbox_sf_bootdev_enabled(void) return !state->disable_sf_bootdevs; } +bool sandbox_serial_is_tty(void) +{ + struct sandbox_state *state = state_get_current(); + + return state->serial_is_tty; +} + int state_init(void) { state = &main_state; diff --git a/arch/sandbox/include/asm/state.h b/arch/sandbox/include/asm/state.h index 3aa35c112be..5350ee6b8fa 100644 --- a/arch/sandbox/include/asm/state.h +++ b/arch/sandbox/include/asm/state.h @@ -157,6 +157,7 @@ struct sandbox_state { bool ignore_missing_state_on_read; /* No error if state missing */ bool show_lcd; /* Show LCD on start-up */ bool double_lcd; /* Double display size for high-DPI */ + bool serial_is_tty; /* Serial console is connected to a tty */ enum sysreset_t last_sysreset; /* Last system reset type */ bool sysreset_allowed[SYSRESET_COUNT]; /* Allowed system reset types */ enum state_terminal_raw term_raw; /* Terminal raw/cooked */ @@ -377,6 +378,13 @@ int state_get_rel_filename(const char *rel_path, char *buf, int size); */ int state_load_other_fdt(const char **bufp, int *sizep); +/** + * sandbox_serial_is_tty() - check if serial console is connected to a tty + * + * Return: true if serial console is connected to a terminal, false if not + */ +bool sandbox_serial_is_tty(void); + /** * Initialize the test system state */ diff --git a/include/os.h b/include/os.h index 35757fc8bb8..3393acb435a 100644 --- a/include/os.h +++ b/include/os.h @@ -90,6 +90,14 @@ int os_open(const char *pathname, int flags); */ int os_close(int fd); +/** + * os_isatty() - check if file descriptor refers to a terminal + * + * @fd: File descriptor to check + * Return: 1 if fd is a terminal, 0 if not, -1 on error + */ +int os_isatty(int fd); + /** * os_unlink() - access to the OS unlink() system call * diff --git a/include/serial.h b/include/serial.h index 9ed3793b647..02c28f8605c 100644 --- a/include/serial.h +++ b/include/serial.h @@ -2,6 +2,9 @@ #define __SERIAL_H__ #include <post.h> +#ifdef CONFIG_SANDBOX +#include <asm/state.h> +#endif /* Escape value */ #define cESC '\x1b' @@ -424,4 +427,22 @@ int serial_query_size(int *rowsp, int *colsp); */ int serial_get_size(struct udevice *dev, int *rowsp, int *colsp); +/* + * serial_is_tty() - check if the serial console is connected to a terminal + * + * This does not indicate that there is actually a terminal, only that if there + * is one, we can assume it is present and connected + * + * Return: true if any serial console is likely connected to a terminal, false if not + */ +static inline bool serial_is_tty(void) +{ +#ifdef CONFIG_SANDBOX + return sandbox_serial_is_tty(); +#else + /* assume that it is! */ + return true; +#endif +} + #endif -- 2.43.0