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- #ident "$Id: hello2.c,v 1.4 2004/12/14 22:46:25 hpa Exp $"
- /* ----------------------------------------------------------------------- *
- *
- * 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,
- * Boston MA 02111-1307, USA; either version 2 of the License, or
- * (at your option) any later version; incorporated herein by reference.
- *
- * ----------------------------------------------------------------------- */
-
- /*
- * hello2.c
- *
- * Simple COM32 image
- *
- * This version shows how to use the bounce buffer for data transfer
- * to the BIOS or COMBOOT system calls.
- */
-
- #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");
- }
-
- static void strcpy(char *dst, const char *src)
- {
- while ( *src )
- *dst++ = *src++;
-
- *dst = '\0';
- }
-
- static void writemsg(const char *msg)
- {
- com32sys_t inreg;
-
- memset(&inreg, 0, sizeof inreg);
-
- strcpy(__com32.cs_bounce, msg);
- inreg.eax.w[0] = 0x0002; /* Write string */
- inreg.ebx.w[0] = OFFS(__com32.cs_bounce);
- inreg.es = SEG(__com32.cs_bounce);
- __com32.cs_intcall(0x22, &inreg, NULL);
- };
-
- int __start(void)
- {
- writemsg("Hello, World!\r\n"
- "cmdline = ");
- writemsg(__com32.cs_cmdline);
- writemsg("\r\n");
- return 0;
- }
-