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1 files changed, 116 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/core/ansiesc.c b/contrib/syslinux-4.02/gpxe/src/core/ansiesc.c
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+++ b/contrib/syslinux-4.02/gpxe/src/core/ansiesc.c
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <string.h>
+#include <assert.h>
+#include <gpxe/ansiesc.h>
+
+/** @file
+ *
+ * ANSI escape sequences
+ *
+ */
+
+/**
+ * Call ANSI escape sequence handler
+ *
+ * @v handlers List of escape sequence handlers
+ * @v function Control function identifier
+ * @v count Parameter count
+ * @v params Parameter list
+ */
+static void ansiesc_call_handler ( struct ansiesc_handler *handlers,
+ unsigned int function, int count,
+ int params[] ) {
+ struct ansiesc_handler *handler;
+
+ for ( handler = handlers ; handler->function ; handler++ ) {
+ if ( handler->function == function ) {
+ handler->handle ( count, params );
+ break;
+ }
+ }
+}
+
+/**
+ * Process character that may be part of ANSI escape sequence
+ *
+ * @v ctx ANSI escape sequence context
+ * @v c Character
+ * @ret c Original character if not part of escape sequence
+ * @ret <0 Character was part of escape sequence
+ *
+ * ANSI escape sequences will be plucked out of the character stream
+ * and interpreted; once complete they will be passed to the
+ * appropriate handler if one exists in this ANSI escape sequence
+ * context.
+ *
+ * In the interests of code size, we are rather liberal about the
+ * sequences we are prepared to accept as valid.
+ */
+int ansiesc_process ( struct ansiesc_context *ctx, int c ) {
+ if ( ctx->count == 0 ) {
+ if ( c == ESC ) {
+ /* First byte of CSI : begin escape sequence */
+ ctx->count = 1;
+ memset ( ctx->params, 0xff, sizeof ( ctx->params ) );
+ ctx->function = 0;
+ return -1;
+ } else {
+ /* Normal character */
+ return c;
+ }
+ } else {
+ if ( c == '[' ) {
+ /* Second byte of CSI : do nothing */
+ } else if ( ( c >= '0' ) && ( c <= '9' ) ) {
+ /* Parameter Byte : part of a parameter value */
+ int *param = &ctx->params[ctx->count - 1];
+ if ( *param < 0 )
+ *param = 0;
+ *param = ( ( *param * 10 ) + ( c - '0' ) );
+ } else if ( c == ';' ) {
+ /* Parameter Byte : parameter delimiter */
+ ctx->count++;
+ if ( ctx->count > ( sizeof ( ctx->params ) /
+ sizeof ( ctx->params[0] ) ) ) {
+ /* Excessive parameters : abort sequence */
+ ctx->count = 0;
+ DBG ( "Too many parameters in ANSI escape "
+ "sequence\n" );
+ }
+ } else if ( ( c >= 0x20 ) && ( c <= 0x2f ) ) {
+ /* Intermediate Byte */
+ ctx->function <<= 8;
+ ctx->function |= c;
+ } else {
+ /* Treat as Final Byte. Zero ctx->count before
+ * calling handler to avoid potential infinite loops.
+ */
+ int count = ctx->count;
+ ctx->count = 0;
+ ctx->function <<= 8;
+ ctx->function |= c;
+ ansiesc_call_handler ( ctx->handlers, ctx->function,
+ count, ctx->params );
+ }
+ return -1;
+ }
+}