[efi] Include installed protocol list in unknown handle names
[ipxe.git] / src / core / console.c
1 #include "stddef.h"
2 #include <ipxe/console.h>
3 #include <ipxe/process.h>
4 #include <ipxe/nap.h>
5
6 /** @file */
7
8 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
9
10 /** Current console usage */
11 int console_usage = CONSOLE_USAGE_STDOUT;
12
13 /** Console width */
14 unsigned int console_width = CONSOLE_DEFAULT_WIDTH;
15
16 /** Console height */
17 unsigned int console_height = CONSOLE_DEFAULT_HEIGHT;
18
19 /**
20 * Write a single character to each console device
21 *
22 * @v character Character to be written
23 *
24 * The character is written out to all enabled console devices, using
25 * each device's console_driver::putchar() method.
26 */
27 void putchar ( int character ) {
28 struct console_driver *console;
29
30 /* Automatic LF -> CR,LF translation */
31 if ( character == '\n' )
32 putchar ( '\r' );
33
34 for_each_table_entry ( console, CONSOLES ) {
35 if ( ( ! ( console->disabled & CONSOLE_DISABLED_OUTPUT ) ) &&
36 ( console_usage & console->usage ) &&
37 console->putchar )
38 console->putchar ( character );
39 }
40 }
41
42 /**
43 * Check to see if any input is available on any console
44 *
45 * @ret console Console device that has input available, or NULL
46 *
47 * All enabled console devices are checked once for available input
48 * using each device's console_driver::iskey() method. The first
49 * console device that has available input will be returned, if any.
50 */
51 static struct console_driver * has_input ( void ) {
52 struct console_driver *console;
53
54 for_each_table_entry ( console, CONSOLES ) {
55 if ( ( ! ( console->disabled & CONSOLE_DISABLED_INPUT ) ) &&
56 console->iskey ) {
57 if ( console->iskey () )
58 return console;
59 }
60 }
61 return NULL;
62 }
63
64 /**
65 * Read a single character from any console
66 *
67 * @ret character Character read from a console.
68 *
69 * A character will be read from the first enabled console device that
70 * has input available using that console's console_driver::getchar()
71 * method. If no console has input available to be read, this method
72 * will block. To perform a non-blocking read, use something like
73 *
74 * @code
75 *
76 * int key = iskey() ? getchar() : -1;
77 *
78 * @endcode
79 *
80 * The character read will not be echoed back to any console.
81 */
82 int getchar ( void ) {
83 struct console_driver *console;
84 int character;
85
86 while ( 1 ) {
87 console = has_input();
88 if ( console && console->getchar ) {
89 character = console->getchar ();
90 break;
91 }
92
93 /* Doze for a while (until the next interrupt). This works
94 * fine, because the keyboard is interrupt-driven, and the
95 * timer interrupt (approx. every 50msec) takes care of the
96 * serial port, which is read by polling. This reduces the
97 * power dissipation of a modern CPU considerably, and also
98 * makes Etherboot waiting for user interaction waste a lot
99 * less CPU time in a VMware session.
100 */
101 cpu_nap();
102
103 /* Keep processing background tasks while we wait for
104 * input.
105 */
106 step();
107 }
108
109 /* CR -> LF translation */
110 if ( character == '\r' )
111 character = '\n';
112
113 return character;
114 }
115
116 /**
117 * Check for available input on any console
118 *
119 * @ret is_available Input is available on a console
120 *
121 * All enabled console devices are checked once for available input
122 * using each device's console_driver::iskey() method. If any console
123 * device has input available, this call will return true. If this
124 * call returns true, you can then safely call getchar() without
125 * blocking.
126 */
127 int iskey ( void ) {
128 return has_input() ? 1 : 0;
129 }
130
131 /**
132 * Configure console
133 *
134 * @v config Console configuration
135 * @ret rc Return status code
136 *
137 * The configuration is passed to all configurable consoles, including
138 * those which are currently disabled. Consoles may choose to enable
139 * or disable themselves depending upon the configuration.
140 *
141 * If configuration fails, then all consoles will be reset.
142 */
143 int console_configure ( struct console_configuration *config ) {
144 struct console_driver *console;
145 int rc;
146
147 /* Reset console width and height */
148 console_set_size ( CONSOLE_DEFAULT_WIDTH, CONSOLE_DEFAULT_HEIGHT );
149
150 /* Try to configure each console */
151 for_each_table_entry ( console, CONSOLES ) {
152 if ( ( console->configure ) &&
153 ( ( rc = console->configure ( config ) ) != 0 ) )
154 goto err;
155 }
156
157 return 0;
158
159 err:
160 /* Reset all consoles, avoiding a potential infinite loop */
161 if ( config )
162 console_reset();
163 return rc;
164 }