console.h File Reference

User interaction. More...

#include <gpxe/tables.h>

Go to the source code of this file.

Data Structures
struct	console_driver
	A console driver. More...
Defines
#define	CONSOLES   __table ( struct console_driver, "consoles" )
	Console driver table.
#define	__console_driver   __table_entry ( CONSOLES, 01 )
	Mark a struct console_driver as being part of the console drivers table.
Functions
	FILE_LICENCE (GPL2_OR_LATER)
void	putchar (int character)
	Write a single character to each console device.
int	getchar (void)
	Read a single character from any console.
int	iskey (void)
	Check for available input on any console.
int	getkey (void)
	Get single keypress.

---

Detailed Description

User interaction.

Various console devices can be selected via the build options CONSOLE_FIRMWARE, CONSOLE_SERIAL etc. The console functions putchar(), getchar() and iskey() delegate to the individual console drivers.

Definition in file console.h.

---

Define Documentation

#define CONSOLES   __table ( struct console_driver, "consoles" )

Console driver table.

Definition at line 91 of file console.h.

Referenced by has_input(), and putchar().

struct console_driver serial_console __console_driver   __table_entry ( CONSOLES, 01 ) [read]

Mark a struct console_driver as being part of the console drivers table.

Use as e.g.

   struct console_driver my_console __console_driver = {
      .putchar = my_putchar,
        .getchar = my_getchar,
        .iskey = my_iskey,
   };

Definition at line 110 of file console.h.

---

Function Documentation

FILE_LICENCE

(

GPL2_OR_LATER

)

void putchar

(

int

character

)

Write a single character to each console device.

Parameters:

character

Character to be written

Return values:

None

-

Exceptions:

None

-

The character is written out to all enabled console devices, using each device's console_driver::putchar() method.

Definition at line 21 of file console.c.

References CONSOLES, console_driver::disabled, for_each_table_entry, console_driver::putchar, and putchar().

Referenced by ansiscr_putc(), clrline(), eepro_poll(), epic100_open(), falcon_init_xmac(), get_eeprom_data(), int21(), print_user_string(), printf_putchar(), putchar(), readline(), and sync_console().

                               {
        struct console_driver *console;

        /* Automatic LF -> CR,LF translation */
        if ( character == '\n' )
                putchar ( '\r' );

        for_each_table_entry ( console, CONSOLES ) {
                if ( ( ! console->disabled ) && console->putchar )
                        console->putchar ( character );
        }
}

int getchar

(

void

)

Read a single character from any console.

Parameters:

None

-

Return values:

character

Character read from a console.

Exceptions:

None

-

A character will be read from the first enabled console device that has input available using that console's console_driver::getchar() method. If no console has input available to be read, this method will block. To perform a non-blocking read, use something like

   int key = iskey() ? getchar() : -1;

The character read will not be echoed back to any console.

Definition at line 80 of file console.c.

References cpu_nap(), console_driver::getchar, has_input(), and step().

Referenced by ansiscr_getc(), getchar_timeout(), getkey(), iflinkwait(), int21(), monojob_wait(), more(), pause(), and shell_banner().

                     {
        struct console_driver *console;
        int character;

        while ( 1 ) {
                console = has_input();
                if ( console && console->getchar ) {
                        character = console->getchar ();
                        break;
                }

                /* Doze for a while (until the next interrupt).  This works
                 * fine, because the keyboard is interrupt-driven, and the
                 * timer interrupt (approx. every 50msec) takes care of the
                 * serial port, which is read by polling.  This reduces the
                 * power dissipation of a modern CPU considerably, and also
                 * makes Etherboot waiting for user interaction waste a lot
                 * less CPU time in a VMware session.
                 */
                cpu_nap();

                /* Keep processing background tasks while we wait for
                 * input.
                 */
                step();
        }

        /* CR -> LF translation */
        if ( character == '\r' )
                character = '\n';

        return character;
}

int iskey

(

void

)

Check for available input on any console.

Parameters:

None

-

Return values:

	True	Input is available on a console
	False	Input is not available on any console

Exceptions:

None

-

All enabled console devices are checked once for available input using each device's console_driver::iskey() method. If any console device has input available, this call will return True. If this call returns True, you can then safely call getchar() without blocking.

Definition at line 128 of file console.c.

References has_input().

Referenced by ansiscr_peek(), getchar_timeout(), iflinkwait(), int21(), monojob_wait(), pxe_menu_prompt_and_select(), pxe_menu_select(), and shell_banner().

                   {
        return has_input() ? 1 : 0;
}

int getkey

(

void

)

Get single keypress.

Return values:

key

Key pressed

The returned key will be an ASCII value or a KEY_XXX special constant. This function differs from getchar() in that getchar() will return "special" keys (e.g. cursor keys) as a series of characters forming an ANSI escape sequence.

Definition at line 63 of file getkey.c.

References ESC, getchar(), getchar_timeout(), GETKEY_TIMEOUT, isdigit, and KEY_ANSI.

Referenced by login_ui(), main_loop(), pxe_menu_prompt_and_select(), pxe_menu_select(), and readline().

                    {
        int character;
        unsigned int n = 0;

        character = getchar();
        if ( character != ESC )
                return character;

        while ( ( character = getchar_timeout ( GETKEY_TIMEOUT ) ) >= 0 ) {
                if ( character == '[' )
                        continue;
                if ( isdigit ( character ) ) {
                        n = ( ( n * 10 ) + ( character - '0' ) );
                        continue;
                }
                if ( character >= 0x40 )
                        return KEY_ANSI ( n, character );
        }

        return ESC;
}