/* This program will reassign all the standard assigned names to be the proper
   usual directories on a new disk.  The names are:

	C:  DEVS:  FONTS:  L:  LIBS:  S:  and SYS:

   This program will assign SYS: to the given volume and each of the other
   names to the directory of SYS: with that same name (C: = SYS:c etc).
   
   It's called MoveSys.  Hard disk users can put it in their Startup-Sequence
   to ease the transition from the floppy boot disk (or RAD:) to the hard
   disk.  Non-hard-disk users can use it to switch from one bootable
   application disk to another without getting "please insert volume
   Workbench 1.3" or the like all the time.  For Aztec C.  If you want
   flexibility, customize the source code.  Usage:

	MoveSys name:		; where name is a volume name or drive name

   You can even MoveSys to a directory, if the appropriate subdirectories
   are present there.  Like, MoveSys dh0:Workbench or something.

   By Paul Kienitz, 12/10/88.  Public domain.  For Aztec C only; do not
   compile with the +m flag.  The result is "pure" and can be made resident.
   
   1/17/89:  Ooops!  Had to add DosAllocate, because unassigning a node I
   created without that could cause bad craziness.  I should put DosAllocate
   into AssignDev, though it's probably not needed if I fix the bug in
   detecting whether a node it's deleting is one it made, which I think
   somebody already did.

   4/14/89:  Stripped down internally (no stdio, for instance) to reduce size
   and make "pure".  Added IoErr code return.

   ADD LATER:   arguments after volume name to be exceptions or additions to
   		 the built-in list of assignments.
		ability to run from workbench, using workbench message and
		 tooltypes.
		make it not reassign SYS: when locks fail on dirs?
 */



#include <exec/types.h>
#include <exec/nodes.h>
#include <exec/lists.h>
#include <exec/memory.h>
#include <exec/ports.h>
#include <exec/libraries.h>
#include <exec/devices.h>
#include <exec/io.h>
#include <libraries/dosextens.h>
#include <libraries/filehandler.h>
#ifdef AZTEC_C
#include <functions.h>
#endif
#include <Paul.h>  /* defines null, adr, str, bool, bip, gbip, AllocXX ... */


typedef struct DeviceNode den;
typedef BPTR lock;

#define HowMany 6
char *dames[HowMany] = {"C", "DEVS", "FONTS", "L", "LIBS", "S"};
char *dears[HowMany] = {"SYS:c", "SYS:devs", "SYS:fonts", "SYS:l",
			"SYS:libs", "SYS:s"};
/* SYS: gets assigned to the volume named in the command line argument (or
   workbench message argument someday), and then each name in dames gets
   assigned to the corresponding directory name in dears.  You can change
   dears to e.g. assign C: to RAM:C or whatever, or add more names to each,
   incrementing HowMany to match. */


/* the only global variables are unchanging, e.g. library bases */

extern struct DosLibrary *DOSBase;
struct DosInfo *infoo;			/* contains the root of the dev list */



#undef put  /* defined as fputs(stdout, S) in Paul.h */

void put(s) str s;
{	long o = Output();
	if (o) Write(o, s, (long) strlen(s));
}



/* Allocate a block of memory the way the Dos does, with size (rounded up to
   the nearest multiple of four) in the longword below the address returned */

adr DosAllocate(size) int size;
{
	long longlen = (size + 7) & ~3L;
	long *dosalloc = AllocPZ(longlen);
	if (!dosalloc) return (null);
	*dosalloc = longlen;
	return (dosalloc + 1);
}



void DosFree(a) long *a;
{	FreeMem(a - 1, a[-1]);
}



den *MakeNewAssignNode(name) str name;   /* do this within a Forbid */
{	
	den *foo = DosAllocate(sizeof(den));
	int len = strlen(name);
	str nom;
	if (!foo) return (null);
	if (!(nom = DosAllocate(len + 2))) {  /* room for length byte AND  */
		DosFree(foo);                 /*  nul, like existing nodes */
		return (null);
	}
	foo->dn_Name = (long) nom >> 2;
	foo->dn_Type = 1L;
	nom[0] = len;
	strcpy(nom + 1, name);	/* leave the nul on the end */
	foo->dn_Next = infoo->di_DevInfo;    /* put new node at top of list */
	infoo->di_DevInfo = (long) foo >> 2;
	return (foo);
}



bool Match(s, b) str s; BSTR b;
{
	str bee = bip(char, b);
	short len = strlen(s);
	short i;
	if (bee[0] != len) return (false);
	for (i = 0; i < len; i++)
		if (toupper(s[i]) != toupper(bee[i + 1]))
			return (false);
	return (true);
}



den *FindDNode(name) str name;
{
	den *goob;
	for (goob = gbip(infoo->di_DevInfo); goob; goob = gbip(goob->dn_Next))
		if (goob->dn_Type == 1 && Match(name, goob->dn_Name))
			return (goob);
	return (null);
}



bool ReAssign(name, lok) str name; lock lok;
{
	den *where;
	lock old;
	Forbid();
	where = FindDNode(name);
	if (!where) where = MakeNewAssignNode(name);
	if (!where) {
		Permit();
		put("Couldn't find or create device node for \"");
		put(name);
		put("\".\nOut of memory, I guess.\n");
		return (false);
	}
	old = where->dn_Lock;
	where->dn_Lock = lok;
	where->dn_Task = bip(struct FileLock, lok)->fl_Task;
	Permit();
	UnLock(old);
	return (true);
}




long _main(alen, aptr) long alen; str aptr;
{
	lock syl, L;
	short f;
	long hair = 0, turn = 0;
	struct Process *me = (adr) FindTask(null);

	infoo = bip(struct DosInfo, 
		    ((struct RootNode *) DOSBase->dl_Root) ->rn_Info);
	while (alen && aptr[alen - 1] <= ' ') aptr[--alen] = 0;
	if (*aptr == '"') {
		if (aptr[alen - 1] == '"') aptr[--alen] = 0;
		aptr++;
	}
	if (alen && !(alen == 1 && *aptr == '?'))
		syl = (BPTR) RLock(aptr);
	else {
		put(
"You must name a drive, volume, or directory to move SYS: to.\n");
		me->pr_Result2 = ERROR_LINE_TOO_LONG;
		return (10L);
	}
	if (!syl) {
		hair = me->pr_Result2;			/* set by Lock */
		put("MoveSys couldn't find drive/volume \"");
		put(aptr);
		put("\".\n");
		me->pr_Result2 = hair;
		return (10L);
	}
	if (!ReAssign("SYS", syl)) {
		turn = 10;
		hair = ERROR_NO_FREE_STORE;
	} else for (f = 0; f < HowMany; f++) {
		L = (BPTR) RLock(dears[f]);
		if (!L) {
			turn = 5;
			hair = me->pr_Result2;    /* set by Lock */
			put("MoveSys couldn't find directory \"");
			put(dears[f]);
			put("\" (SYS: = \"");
			put(aptr);
			put("\").\n");
		} else
			if (!ReAssign(dames[f], L)) {
				turn = 10;
				hair = ERROR_NO_FREE_STORE;
				break;
			}
	}
	me->pr_Result2 = hair;
	return (turn);
}