multiboot.c

一个操作系统的源代码

/** multiboot.c                                  
 **                                                              
 ** Original Author: Kasper Verdich Lund                         
 ** Date: 10.26.99     
 ** 
 ** Description:
 ** Routines for handling the multiboot information     
 **                                       
 ** Revision History: 
 ** First version     
 **
 ** 0.0.1 10.26.99 Kasper Verdich Lund - (no comments)
 **
 ** 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 or 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                                    
 **                                                              
 *********************************************************Apostle OS**/

#include <types.h>
#include <multiboot.h>
#include <halt.h>
#include <string.h>
#include <mem.h>

#ifdef DEBUG
#include <debug/conio.h>
#endif

dword AvailableMemory(multibootInfo *bootInfo)
{
  if (bootInfo->flags & MULTIBOOT_MEMORY) 
    {
      return ((bootInfo->memoryUpper + 1024) << 10); 
    }
  else
    {
      /* this shouldn't happen - the bootloader has
       * to provide information on available memory */
#ifdef DEBUG
      DebugPrintF("No memory information!\n");
#endif
      halt();
    }
}

dword UsedMemory(multibootInfo *bootInfo)
{
  int i;
  extern void end;
  dword top = (dword)&end;

  if (bootInfo->flags & MULTIBOOT_MODS)
    {
      for (i=0; i<bootInfo->modulesCount; i++)
        if (bootInfo->modules[i].end > top)
          top = bootInfo->modules[i].end;
    }

  top = (top + 4095) & 0xFFFFF000;
  return top;
}

multibootInfo *CopyMultibootInfo(multibootInfo *bootInfo)
{
  multibootInfo *newInfo;
  newInfo = malloc(sizeof(multibootInfo));
  memcpy(newInfo,bootInfo,sizeof(multibootInfo));
  newInfo->commandLine = malloc(strlen(bootInfo->commandLine)+1);
  strcpy(newInfo->commandLine,bootInfo->commandLine);
  if (newInfo->flags & MULTIBOOT_MODS) 
    {
      int i;
      newInfo->modules = malloc(sizeof(multibootModule)*newInfo->modulesCount);
      memcpy(newInfo->modules,bootInfo->modules,sizeof(multibootModule)*newInfo->modulesCount);
      for (i=0;i<newInfo->modulesCount;i++)
        {
          newInfo->modules[i].string = malloc(strlen(bootInfo->modules[i].string)+1);
          strcpy(newInfo->modules[i].string,bootInfo->modules[i].string);
        }
    }
  return newInfo;
}