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author | 2015-08-28 09:58:54 +0800 | |
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committer | 2015-09-01 12:44:00 +0800 | |
commit | e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch) | |
tree | 66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/core/console.c | |
parent | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff) |
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/core/console.c')
-rw-r--r-- | qemu/roms/ipxe/src/core/console.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/core/console.c b/qemu/roms/ipxe/src/core/console.c new file mode 100644 index 000000000..141d8f0f0 --- /dev/null +++ b/qemu/roms/ipxe/src/core/console.c @@ -0,0 +1,164 @@ +#include "stddef.h" +#include <ipxe/console.h> +#include <ipxe/process.h> +#include <ipxe/nap.h> + +/** @file */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +/** Current console usage */ +int console_usage = CONSOLE_USAGE_STDOUT; + +/** Console width */ +unsigned int console_width = CONSOLE_DEFAULT_WIDTH; + +/** Console height */ +unsigned int console_height = CONSOLE_DEFAULT_HEIGHT; + +/** + * Write a single character to each console device + * + * @v character Character to be written + * + * The character is written out to all enabled console devices, using + * each device's console_driver::putchar() method. + */ +void putchar ( int character ) { + struct console_driver *console; + + /* Automatic LF -> CR,LF translation */ + if ( character == '\n' ) + putchar ( '\r' ); + + for_each_table_entry ( console, CONSOLES ) { + if ( ( ! ( console->disabled & CONSOLE_DISABLED_OUTPUT ) ) && + ( console_usage & console->usage ) && + console->putchar ) + console->putchar ( character ); + } +} + +/** + * Check to see if any input is available on any console + * + * @ret console Console device that has input available, or NULL + * + * All enabled console devices are checked once for available input + * using each device's console_driver::iskey() method. The first + * console device that has available input will be returned, if any. + */ +static struct console_driver * has_input ( void ) { + struct console_driver *console; + + for_each_table_entry ( console, CONSOLES ) { + if ( ( ! ( console->disabled & CONSOLE_DISABLED_INPUT ) ) && + console->iskey ) { + if ( console->iskey () ) + return console; + } + } + return NULL; +} + +/** + * Read a single character from any console + * + * @ret character Character read from a console. + * + * 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 + * + * @code + * + * int key = iskey() ? getchar() : -1; + * + * @endcode + * + * The character read will not be echoed back to any console. + */ +int getchar ( void ) { + 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; +} + +/** + * Check for available input on any console + * + * @ret is_available Input is available on a console + * + * 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. + */ +int iskey ( void ) { + return has_input() ? 1 : 0; +} + +/** + * Configure console + * + * @v config Console configuration + * @ret rc Return status code + * + * The configuration is passed to all configurable consoles, including + * those which are currently disabled. Consoles may choose to enable + * or disable themselves depending upon the configuration. + * + * If configuration fails, then all consoles will be reset. + */ +int console_configure ( struct console_configuration *config ) { + struct console_driver *console; + int rc; + + /* Reset console width and height */ + console_set_size ( CONSOLE_DEFAULT_WIDTH, CONSOLE_DEFAULT_HEIGHT ); + + /* Try to configure each console */ + for_each_table_entry ( console, CONSOLES ) { + if ( ( console->configure ) && + ( ( rc = console->configure ( config ) ) != 0 ) ) + goto err; + } + + return 0; + + err: + /* Reset all consoles, avoiding a potential infinite loop */ + if ( config ) + console_reset(); + return rc; +} |