From 8363c19687e3fa6c2ec394c2129bfa837900ab37 Mon Sep 17 00:00:00 2001
From: Bruce Evans <bde@FreeBSD.org>
Date: Thu, 13 Feb 1997 13:15:47 +0000
Subject: [PATCH] Get defaults for the boot device (and flags) from the file
 "boot.config" (relative to the root directory on the 'a' partition on the
 first BSD slice) if it exists.  If it doesn't exist, then the only visible
 changes should be that the kernel name isn't reset to "/kernel" after looking
 it up fails and that the default name is now "kernel".

The new function readfile() can be used for other things:
- reading help messages.
- reading splash screens.
- reading userconfig info.
---
 sys/i386/boot/biosboot/boot.c | 64 ++++++++++++++++++++++++++---------
 1 file changed, 48 insertions(+), 16 deletions(-)

diff --git a/sys/i386/boot/biosboot/boot.c b/sys/i386/boot/biosboot/boot.c
index 03e8f492145..84cd4a720ad 100644
--- a/sys/i386/boot/biosboot/boot.c
+++ b/sys/i386/boot/biosboot/boot.c
@@ -62,8 +62,10 @@ WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 #define	ouraddr	(BOOTSEG << 4)		/* XXX */
 
+#define	BOOT_CONFIG_SIZE	512
 #define NAMEBUF_LEN	(8*1024)
 
+static char boot_config[BOOT_CONFIG_SIZE];
 #ifdef NAMEBLOCK
 char *dflt_name;
 #endif
@@ -74,6 +76,7 @@ int loadflags;
 
 static void getbootdev(char *ptr, int *howto);
 static void loadprog(void);
+static void readfile(char *path, char *buf, size_t nbytes);
 
 /* NORETURN */
 void
@@ -151,8 +154,16 @@ boot(int drive)
 		name = dflt_name;
 	} else
 #endif	/*NAMEBLOCK*/
+	name = "kernel";
+	readfile("boot.config", boot_config, BOOT_CONFIG_SIZE);
+	getbootdev(boot_config, &loadflags);
+	if (namebuf[0] != '\0')
+		printf("boot.config: %s", boot_config);
+	/*
+	 * XXX parsing of `name' is in openrd(), so the defaults aren't
+	 * updated to match the config (if any) before printing the prompt.
+	 */
 loadstart:
-	name = "/kernel";
 	/* print this all each time.. (saves space to do so) */
 	/* If we have looped, use the previous entries as defaults */
 	printf("\n>> FreeBSD BOOT @ 0x%x: %d/%d k of memory\n"
@@ -163,7 +174,17 @@ loadstart:
 	       dosdev & 0x7f, devs[maj], unit, name);
 
 	loadflags &= RB_SERIAL;	/* clear all, but leave serial console */
-	getbootdev(namebuf, &loadflags);
+
+	/*
+	 * Be paranoid and make doubly sure that the input buffer is empty.
+	 */
+	if (loadflags & RB_SERIAL)
+		init_serial();
+
+	if (!gets(namebuf))
+		putchar('\n');
+	else
+		getbootdev(namebuf, &loadflags);
 	ret = openrd();
 	if (ret != 0) {
 		if (ret > 0)
@@ -306,28 +327,39 @@ loadprog(void)
 		  (int)&bootinfo + ouraddr);
 }
 
-void
+static void
+readfile(char *path, char *buf, size_t nbytes)
+{
+	int openstatus;
+
+	buf[0] = '\0';
+	name = path;
+	openstatus = openrd();
+	if (openstatus != 0) {
+		if (openstatus > 0)
+			printf("Can't find file %s\n", name);
+	} else {
+		/* XXX no way to determine file size. */
+		read(buf, nbytes);
+	}
+	buf[nbytes - 1] = '\0';
+#if 0
+	pcpy(buf, (void *)0x800, nbytes);
+#endif
+}
+
+static void
 getbootdev(char *ptr, int *howto)
 {
 	char c;
 
-	/*
-	 * Be paranoid and make doubly sure that the input buffer is empty.
-	 */
-	if (*howto & RB_SERIAL)
-		init_serial();
-
-	if (!gets(ptr)) {
-		putchar('\n');
-		return;
-	}
 	while ((c = *ptr) != '\0') {
 nextarg:
-		while (c == ' ')
+		while (c == ' ' || c == '\n')
 			c = *++ptr;
 		if (c == '-')
 			while ((c = *++ptr) != '\0') {
-				if (c == ' ')
+				if (c == ' ' || c == '\n')
 					goto nextarg;
 				if (c == 'C')
 					*howto |= RB_CDROM;
@@ -358,7 +390,7 @@ nextarg:
 			return;
 		name = ptr;
 		while (*++ptr != '\0') {
-			if (*ptr == ' ') {
+			if (*ptr == ' ' || *ptr == '\n') {
 				*ptr++ = '\0';
 				break;
 			}