[process] Include process name in debug messages
[ipxe.git] / src / core / ansiesc.c
1 /*
2 * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA.
18 *
19 * You can also choose to distribute this program under the terms of
20 * the Unmodified Binary Distribution Licence (as given in the file
21 * COPYING.UBDL), provided that you have satisfied its requirements.
22 */
23
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25
26 #include <string.h>
27 #include <assert.h>
28 #include <ipxe/ansiesc.h>
29
30 /** @file
31 *
32 * ANSI escape sequences
33 *
34 */
35
36 /**
37 * Call ANSI escape sequence handler
38 *
39 * @v ctx ANSI escape sequence context
40 * @v function Control function identifier
41 * @v count Parameter count
42 * @v params Parameter list
43 */
44 static void ansiesc_call_handler ( struct ansiesc_context *ctx,
45 unsigned int function, int count,
46 int params[] ) {
47 struct ansiesc_handler *handlers = ctx->handlers;
48 struct ansiesc_handler *handler;
49
50 for ( handler = handlers ; handler->function ; handler++ ) {
51 if ( handler->function == function ) {
52 handler->handle ( ctx, count, params );
53 break;
54 }
55 }
56 }
57
58 /**
59 * Process character that may be part of ANSI escape sequence
60 *
61 * @v ctx ANSI escape sequence context
62 * @v c Character
63 * @ret c Original character if not part of escape sequence
64 * @ret <0 Character was part of escape sequence
65 *
66 * ANSI escape sequences will be plucked out of the character stream
67 * and interpreted; once complete they will be passed to the
68 * appropriate handler if one exists in this ANSI escape sequence
69 * context.
70 *
71 * In the interests of code size, we are rather liberal about the
72 * sequences we are prepared to accept as valid.
73 */
74 int ansiesc_process ( struct ansiesc_context *ctx, int c ) {
75
76 if ( ctx->count == 0 ) {
77 if ( c == ESC ) {
78 /* First byte of CSI : begin escape sequence */
79 ctx->count = 1;
80 memset ( ctx->params, 0xff, sizeof ( ctx->params ) );
81 ctx->function = 0;
82 return -1;
83 } else {
84 /* Normal character */
85 return c;
86 }
87 } else {
88 if ( c == '[' ) {
89 /* Second byte of CSI : do nothing */
90 } else if ( ( c >= '0' ) && ( c <= '9' ) ) {
91 /* Parameter Byte : part of a parameter value */
92 int *param = &ctx->params[ctx->count - 1];
93 if ( *param < 0 )
94 *param = 0;
95 *param = ( ( *param * 10 ) + ( c - '0' ) );
96 } else if ( c == ';' ) {
97 /* Parameter Byte : parameter delimiter */
98 ctx->count++;
99 if ( ctx->count > ( sizeof ( ctx->params ) /
100 sizeof ( ctx->params[0] ) ) ) {
101 /* Excessive parameters : abort sequence */
102 ctx->count = 0;
103 DBG ( "Too many parameters in ANSI escape "
104 "sequence\n" );
105 }
106 } else if ( ( ( c >= 0x20 ) && ( c <= 0x2f ) ) ||
107 ( c == '?' ) ) {
108 /* Intermediate Byte */
109 ctx->function <<= 8;
110 ctx->function |= c;
111 } else {
112 /* Treat as Final Byte. Zero ctx->count before
113 * calling handler to avoid potential infinite loops.
114 */
115 int count = ctx->count;
116 ctx->count = 0;
117 ctx->function <<= 8;
118 ctx->function |= c;
119 ansiesc_call_handler ( ctx, ctx->function,
120 count, ctx->params );
121 }
122 return -1;
123 }
124 }