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-rw-r--r--qemu/roms/ipxe/src/core/console.c164
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
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+#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;
+}