/* getdisks.c - Grab all available disk devices and return them to you in a
 * 		simple exec list. The list is made up of named nodes--the "names"
 *	 	being the device name. 
 *
 * 	 Phillip Lindsay (c) 1987 Commodore-Amiga Inc. 
 * You may use this source as long as the copyright notice is left intact.
 */
#include <exec/types.h>
#include <exec/nodes.h>
#include <exec/lists.h>
#include <exec/memory.h>
#include <libraries/dos.h>
#include <libraries/dosextens.h>
#include <libraries/filehandler.h>

#ifdef MANX
#include <functions.h>
#include <stdio.h>
#else
#include <lattice/stdio.h>
#endif

extern struct DosLibrary *DOSBase;

/* btoc() takes a pointer to a string in BCPL format and converts it to a
 * C string.
 */
void *btoc(bstring)
char *bstring;
{
 register UBYTE len,count,*cstring; 
 
 cstring = (UBYTE *) bstring;
 len = cstring[0];              
 for(count=0;count < len;count++)
  cstring[count] = cstring[count+1];
 cstring[count] = '\0';
}

/* GetNode() will build a node structure for you. It will append memory to the
 * 	node structure for the node name passed.
 */   	
struct Node *GetNode(name,type,pri)
char *name;
UBYTE type,pri;
{
 register struct Node *mynode;
 register char        *myname;
 register UBYTE	      *mymemory;
 register ULONG	      mynamesize;

 mynamesize =( ((ULONG)strlen(name)) ? (ULONG)strlen(name)+1 : 0L );   

 mymemory = (UBYTE *) 
  AllocMem((ULONG)sizeof(*mynode)+mynamesize,MEMF_PUBLIC | MEMF_CLEAR); 

 if(!mymemory) return((struct Node *)NULL);
 
 mynode = (struct Node *) mymemory; 
 if(mynamesize)
  {
   myname = (char *) mymemory+(ULONG)sizeof(*mynode);
   strcpy(myname,name);
   mynode->ln_Name = myname;
  }
 mynode->ln_Type = type;
 mynode->ln_Pri  = pri;

 return(mynode);
}

/* This function assumes you used GetNode() for node initialization. Will
 * 	free all memory used by node. Make sure you remove node from any list. 
 */
void FreeNode(mynode)
struct Node *mynode;
{
 register ULONG mymemsize;

 mymemsize = (ULONG) sizeof(*mynode);
 mymemsize+= ((mynode->ln_Name) ? (ULONG)strlen(mynode->ln_Name)+1 : 0L);
 
 FreeMem(mynode,mymemsize);
}


/* getdisks() will grab all disk device names in the system device list and
 *  append an exec node to a given list. The node being named in respect to the
 *  device.  
 */
void getdisks(dlist)
struct List *dlist;	/* passed a pointer to a initialize exec list */ 
{
 extern struct DosLibrary 	  *DOSBase;
 struct RootNode	  	  *rnode; 
 struct DosInfo	  		  *dinfo;
 register struct DeviceNode	  *dnode;
 register struct Node 		  *adisk;
 char	  *bname,name[32];

 rnode   = (struct RootNode *)  DOSBase->dl_Root;
 dinfo   = (struct DosInfo  *)  BADDR(rnode->rn_Info);
 
 Forbid();
 for(dnode = (struct DeviceNode *) BADDR(dinfo->di_DevInfo);BADDR(dnode);
 	dnode = (struct DeviceNode *) BADDR(dnode->dn_Next))
  {
   if(!dnode->dn_Type && dnode->dn_Task && BADDR(dnode->dn_Name)) 
    {
     bname = (char *) BADDR(dnode->dn_Name);    
     movmem(bname,name,(ULONG)bname[0]+1L);
     btoc(name);
     if((adisk=GetNode(name,0,0))) AddTail(dlist,adisk);    
    }
  }
 Permit(); 
}

/* freedisks() will free all nodes in a given list. Function assumes nodes where
 *    initialized with GetNode().
 */
void freedisks(dlist)
struct List *dlist;
{
 register struct Node *disk;

 while((disk=RemTail(dlist)))
  FreeNode(disk);
}


main()
{
 struct List disks;
 struct Node *disk;
  
 NewList(&disks);	/* Initialize list header */
 getdisks(&disks);	/* Fill list */
 
/* print any devices in list.... if any */
 if(disks.lh_TailPred != &disks)
   for(disk = disks.lh_Head;disk->ln_Succ;disk=disk->ln_Succ)
     puts(disk->ln_Name);

 freedisks(&disks);
}