/* Copyright (C) 2005 David Decotigny
 
    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 (at your option) 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
    USA. 
 */
 
 #include <crt.h>
 #include <libc.h>
 #include <string.h>
 #include <stdarg.h>
 #include <debug.h>
 
 
 /**
  * @file myprog12.c
  *
  * /dev/mem & /dev/kmem tests
  */
 
 
 int main()
 {
   char *zoup;
 
   /* Test /dev/mem */
 
   /* Map the x86 text framebuffer into this process address space in
      shared mode */
   int fd;
 
   fd = open("/dev/mem", O_RDWR);
   zoup = mmap(0, 4096, PROT_READ | PROT_WRITE,
               MAP_SHARED,
               fd, 0xb8000);
   close(fd);
 
   bochs_printf("mapped mem @%x\n", (unsigned)zoup);  
   _sos_syscall1(4004, (unsigned)"Apres mmap video");
 
   /* Do some forks to complicate things */
   fork();
   fork();
 
   /* Write a string into it: it should be printed on screen */
   strzcpy(zoup + 80*5*2 + 10*2,
           "H e l l o   W o r l d   f r o m   S O S   i n   U s e r   M o d e ",
           250);
 
   /* Map the x86 text framebuffer into this process address space in
      PRIVATE mode */
   fd = open("/dev/mem", O_RDWR);
   zoup = mmap(0, 4096, PROT_READ | PROT_WRITE,
               0 /* Private */,
               fd, 0xb8000);
   close(fd);
   bochs_printf("mapped mem @%x\n", (unsigned)zoup);  
   _sos_syscall1(4004, (unsigned)"Apres mmap video");
 
   /* Do some forks to complicate things */
   fork();
   fork();
 
   /* Write a string into it: it should NOT be printed on screen since
      the mapping is private */
   strzcpy(zoup + 80*5*2 + 10*2,
           "Y o u   c a n n o t   S e e   T h i s ! ",
           250);
 
   /* Test /dev/kmem */
 
   /* remap some kernel pages in user space. We'd better map this in
      "private" mode here, this way we can do whatever we like in this
      area. If we'd mapped it read/write, this would overwrite kernel
      data/code, causing a crash sooner or later. */
   fd = open("/dev/kmem", O_RDWR);
   zoup = mmap(0, 100*4096, PROT_READ | PROT_WRITE,
               0 /* private */,
               fd, 0x00201000);
   close(fd);
   bochs_printf("mapped kmem @%x\n", (unsigned)zoup);  
   _sos_syscall1(4004, (unsigned)"Apres mmap kernel");
 
   /* Do some forks to complicate things */
   fork();
   fork();
 
   /* Overwriting our private "copy" of kernel */
   memset(zoup, 0x0, 10*4096);
   _sos_syscall1(4004, (unsigned)"Apres memset kernel");
 
   return 0;
 }