[syslog] Separate out generic line-based console functionality

Abstract out the generic line-handling portions of the syslog
putchar() routine, to allow use by other console types.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/core/lineconsole.c

@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2012 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 );
+
+/** @file
+ *
+ * Line-based console
+ *
+ */
+
+#include <stdint.h>
+#include <stddef.h>
+#include <ipxe/ansiesc.h>
+#include <ipxe/lineconsole.h>
+
+/** Line-based console ANSI escape sequence handlers */
+static struct ansiesc_handler line_ansiesc_handlers[] = {
+	{ 0, NULL }
+};
+
+/** Line-based console ANSI escape sequence context */
+static struct ansiesc_context line_ansiesc_ctx = {
+	.handlers = line_ansiesc_handlers,
+};
+
+/**
+ * Print a character to a line-based console
+ *
+ * @v character		Character to be printed
+ * @ret print		Print line
+ */
+size_t line_putchar ( struct line_console *line, int character ) {
+
+	/* Strip ANSI escape sequences */
+	character = ansiesc_process ( &line_ansiesc_ctx, character );
+	if ( character < 0 )
+		return 0;
+
+	/* Ignore carriage return */
+	if ( character == '\r' )
+		return 0;
+
+	/* Treat newline as a terminator */
+	if ( character == '\n' )
+		character = 0;
+
+	/* Add character to buffer */
+	line->buffer[line->index++] = character;
+
+	/* Do nothing more unless we reach end-of-line (or end-of-buffer) */
+	if ( ( character != 0 ) &&
+	     ( line->index < ( line->len - 1 /* NUL */ ) ) ) {
+		return 0;
+	}
+
+	/* Reset to start of buffer */
+	line->index = 0;
+
+	return 1;
+}

src/include/ipxe/lineconsole.h

@@ -0,0 +1,33 @@
+#ifndef _IPXE_LINECONSOLE_H
+#define _IPXE_LINECONSOLE_H
+
+/** @file
+ *
+ * Line-based console
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdint.h>
+
+/** A line-based console */
+struct line_console {
+	/** Data buffer
+	 *
+	 * Must initially be filled with NULs
+	 */
+	char *buffer;
+	/** Current index within buffer */
+	size_t index;
+	/** Length of buffer
+	 *
+	 * The final character of the buffer will only ever be used as
+	 * a potential terminating NUL.
+	 */
+	size_t len;
+};
+
+extern size_t line_putchar ( struct line_console *line, int character );
+
+#endif /* _IPXE_LINECONSOLE_H */

src/net/udp/syslog.c

@@ -32,7 +32,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #include <ipxe/dhcp.h>
 #include <ipxe/settings.h>
 #include <ipxe/console.h>
-#include <ipxe/ansiesc.h>
+#include <ipxe/lineconsole.h>
 #include <ipxe/syslog.h>
 
 /** The syslog server */
@@ -61,22 +61,15 @@ static struct interface syslogger = INTF_INIT ( syslogger_desc );
 /** Syslog line buffer */
 static char syslog_buffer[SYSLOG_BUFSIZE];
 
-/** Index into syslog line buffer */
-static unsigned int syslog_idx;
+/** Syslog line console */
+static struct line_console syslog_line = {
+	.buffer = syslog_buffer,
+	.len = sizeof ( syslog_buffer ),
+};
 
 /** Syslog recursion marker */
 static int syslog_entered;
 
-/** Syslog ANSI escape sequence handlers */
-static struct ansiesc_handler syslog_ansiesc_handlers[] = {
-	{ 0, NULL }
-};
-
-/** Syslog ANSI escape sequence context */
-static struct ansiesc_context syslog_ansiesc_ctx = {
-	.handlers = syslog_ansiesc_handlers,
-};
-
 /**
  * Print a character to syslog console
  *
@@ -89,31 +82,10 @@ static void syslog_putchar ( int character ) {
 	if ( syslog_entered )
 		return;
 
-	/* Strip ANSI escape sequences */
-	character = ansiesc_process ( &syslog_ansiesc_ctx, character );
-	if ( character < 0 )
+	/* Fill line buffer */
+	if ( line_putchar ( &syslog_line, character ) == 0 )
 		return;
 
-	/* Ignore carriage return */
-	if ( character == '\r' )
-		return;
-
-	/* Treat newline as a terminator */
-	if ( character == '\n' )
-		character = 0;
-
-	/* Add character to buffer */
-	syslog_buffer[syslog_idx++] = character;
-
-	/* Do nothing more unless we reach end-of-line (or end-of-buffer) */
-	if ( ( character != 0 ) &&
-	     ( syslog_idx < ( sizeof ( syslog_buffer ) - 1 /* NUL */ ) ) ) {
-		return;
-	}
-
-	/* Reset to start of buffer */
-	syslog_idx = 0;
-
 	/* Guard against re-entry */
 	syslog_entered = 1;