Add an API for COMBOOT images, and add support for "COM32" -- 32-bit

linear .com files.

2 files changed, 64 insertions, 1 deletions

diff --git a/sample/Makefile b/sample/Makefile
index f4ad1bcf..e6b648a0 100644
--- a/sample/Makefile
+++ b/sample/Makefile
@@ -15,15 +15,31 @@
 ## samples for syslinux users
 ##
 
+CC         = gcc
+LD         = ld
+CFLAGS     = -O2 -fomit-frame-pointer -I..
+LDFLAGS    = -s
+OBJCOPY    = objcopy
 PPMTOLSS16 = 	../ppmtolss16
 
-all: syslogo.lss
+.SUFFIXES: .lss .c .o .elf .c32
+
+all: syslogo.lss hello.c32
+
+.c.o:
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+.elf.c32:
+	$(OBJCOPY) -O binary $< $@
 
 syslogo.lss:	syslogo.png $(PPMTOLSS16)
 	pngtopnm syslogo.png | \
 		$(PPMTOLSS16) \#000000=0 \#d0d0d0=7 \#f6f6f6=15	\
 		> syslogo.lss
 
+hello.elf: hello.o
+	$(LD) -Ttext 0x101000 -e _start -o $@ $<
+
 clean:
 	rm -f *.lss
 
diff --git a/sample/hello.c b/sample/hello.c
new file mode 100644
index 00000000..194092e3
--- /dev/null
+++ b/sample/hello.c
@@ -0,0 +1,47 @@
+#ident "$Id$"
+/* ----------------------------------------------------------------------- *
+ *   
+ *   Copyright 2002 H. Peter Anvin - All Rights Reserved
+ *
+ *   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, Inc., 53 Temple Place Ste 330,
+ *   Bostom MA 02111-1307, USA; either version 2 of the License, or
+ *   (at your option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * hello.c
+ *
+ * Simple COM32 image
+ */
+
+#include <com32.h>
+
+#define NULL ((void *)0)
+
+static inline void memset(void *buf, int ch, unsigned int len)
+{
+  asm volatile("cld; rep; stosb"
+	       : "+D" (buf), "+c" (len) : "a" (ch) : "memory");
+}
+
+int _start(unsigned int nargs, char *cmdline,
+	   void (*syscall)(unsigned char, com32sys_t *, com32sys_t *),
+	   void *bounce_ptr, unsigned int bounce_len)
+{
+  const char *msg = "Hello, World!\r\n";
+  com32sys_t inreg, outreg;
+  const char *p;
+
+  memset(&inreg, 0, sizeof inreg);
+
+  for ( p = msg ; *p ; p++ ) {
+    inreg.edx = *p;
+    inreg.eax = 0x0200;
+    syscall(0x21, &inreg, NULL);
+  }
+
+  return 0;
+}