fileaccess.c

T-kernel 的extension源代码

/*
 *----------------------------------------------------------------------
 *    T-Kernel / Standard Extension
 *
 *    Copyright (C) 2006 by Ken Sakamura. All rights reserved.
 *    T-Kernel / Standard Extension is distributed 
 *      under the T-License for T-Kernel / Standard Extension.
 *----------------------------------------------------------------------
 *
 *    Version:   1.00.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2006/8/11.
 *
 *----------------------------------------------------------------------
 */

/*
 *	fileaccess.c (memory)
 *
 *	File access routines
 */

#include "segmgr.h"
#include <sys/tkref.h>
#include <extension/seio.h>
#include <stdio.h>
#include <tcode.h>
#include <seio/fcntl.h>


LOCAL	void	num2tc(TC *buf, UW n);

#define TSD_N2T_VAL_8		8
#define TSD_N2T_MSK_0X0F	0x0fU
#define TSD_EFR_VAL_0X00000000	0x00000000
#define TSD_N2T_SFT_4		4
#define TSD_EFC_DES_M1		(-1)

LOCAL const TC numtbl[] = {
  TK_0, TK_1, TK_2, TK_3, TK_4, TK_5, TK_6, TK_7,
  TK_8, TK_9, TK_a, TK_b, TK_c, TK_d, TK_e, TK_f
};

LOCAL void num2tc(TC *buf, UW n)
{
	buf += TSD_N2T_VAL_8;
	*buf-- = TC_NULL;

	*buf-- = numtbl[n & TSD_N2T_MSK_0X0F];
	n >>= TSD_N2T_SFT_4;
	*buf-- = numtbl[n & TSD_N2T_MSK_0X0F];
	n >>= TSD_N2T_SFT_4;
	*buf-- = numtbl[n & TSD_N2T_MSK_0X0F];
	n >>= TSD_N2T_SFT_4;
	*buf-- = numtbl[n & TSD_N2T_MSK_0X0F];
	n >>= TSD_N2T_SFT_4;

	*buf-- = numtbl[n & TSD_N2T_MSK_0X0F];
	n >>= TSD_N2T_SFT_4;
	*buf-- = numtbl[n & TSD_N2T_MSK_0X0F];
	n >>= TSD_N2T_SFT_4;
	*buf-- = numtbl[n & TSD_N2T_MSK_0X0F];
	n >>= TSD_N2T_SFT_4;
	*buf   = numtbl[n & TSD_N2T_MSK_0X0F];
}

EXPORT ER ExecFileCheck(POBJ_HDR *pohdr)
{
	ER	er;

	switch (pohdr->type) {
	  case TPA_LINK:
	  case TMA_LINK:
		er = tkse_chk_fil(pohdr->src.lnk, F_EXCUTE, NULL);
		break;
	  case TPA_SEIO:
	  case TMA_SEIO:
	  case TPA_PTR:
	  case TMA_PTR:
		er = E_OK;
		break;
	  default:
		er = E_PAR;
		break;
	}
	
	return er;
}

EXPORT ER ExecFileOpen(POBJ_HDR *pohdr)
{
	ER	er;

	switch (pohdr->type) {
	  case TPA_LINK:
	  case TMA_LINK:
		er = tkse_opn_fil(pohdr->src.lnk, F_READ|F_WEXCL, NULL);
		break;
	  case TPA_SEIO:
	  case TMA_SEIO:
		er = tkse_open((char*)pohdr->src.path, O_RDONLY, 0);
		break;
	  case TPA_PTR:
	  case TMA_PTR:
		er = ExecPtrOpen(pohdr);
		break;
	  default:
		er = E_PAR;
		break;
	}

	pohdr->desc = (er >= 0) ? er : TSD_EFC_DES_M1;

	return er;
}

EXPORT ER ExecFileGetName(POBJ_HDR *pohdr, TC *name)
{
	ER	er;

	switch (pohdr->type) {
	  case TPA_LINK:
	  case TMA_LINK:
		er = tkse_ofl_sts(pohdr->desc, name, NULL, NULL);
		break;
	  case TPA_SEIO:
	  case TMA_SEIO:
		if (name != NULL) {
			num2tc(name, (UW)pohdr->desc);
		}
		er = E_OK;
		break;
	  case TPA_PTR:
	  case TMA_PTR:
		er = ExecPtrName(pohdr, name);
		break;
	  default:
		er = E_PAR;
		break;
	}

	return er;
}

EXPORT ER ExecFileRead(POBJ_HDR *pohdr,
		       VB *buf, W size, W ofs, W *rsize, VP exinf)
{
	ER	er;
	W	rsz;

	switch (pohdr->type) {
	  case TPA_LINK:
	  case TMA_LINK:
		/* Load the first one byte separately because it cannot
		   be loaded in to an address of 0x00000000 due to
		   specifications of rea_rec(). */
		if (buf == (VB*)TSD_EFR_VAL_0X00000000) {
			VB firstbyte;
			er = tkse_rea_rec(pohdr->desc, ofs, &firstbyte, 1, &rsz, NULL);
			if (er < E_OK) {
				goto ret;
			}
			if (rsz < 1) {
				er = E_REC;
				goto ret;
			}

			*buf++ = firstbyte;
			ofs++;
			size--;
			if (rsize != NULL) {
				*rsize = rsz;
				rsize = NULL;
			}
		}

		er = tkse_rea_rec(pohdr->desc, ofs, buf, size, rsize,
				  (UH*)exinf);
		break;
	  case TPA_SEIO:
	  case TMA_SEIO:
		er = tkse_lseek(pohdr->desc, ofs, SEEK_SET);
		if (er < E_OK) {
			goto ret;
		}
		er = tkse_read(pohdr->desc, buf, (size_t)size);
		if (er < E_OK) {
			goto ret;
		}
		if (rsize != NULL) {
			*rsize = er;
		}
		er = E_OK;
		break;
	  case TPA_PTR:
	  case TMA_PTR:
		er = ExecPtrRead(pohdr, buf, size, ofs, rsize, exinf);
		break;
	  default:
		er = E_PAR;
		break;
	}

 ret:
	return er;
}

EXPORT ER ExecFileClose(POBJ_HDR *pohdr)
{
	ER	er;

	switch (pohdr->type) {
	  case TPA_LINK:
	  case TMA_LINK:
		er = tkse_cls_fil(pohdr->desc);
		break;
	  case TPA_SEIO:
	  case TMA_SEIO:
		er = tkse_close(pohdr->desc);
		break;
	  case TPA_PTR:
	  case TMA_PTR:
		er = ExecPtrClose(pohdr);
		break;
	  default:
		er = E_PAR;
		break;
	}

	pohdr->desc = TSD_EFC_DES_M1;

	return er;
}

EXPORT ER ExecFileRecInfo(POBJ_HDR *pohdr, W *offset, W *recsize,
			  PhyBlk *block, W entry_len, W *n_entry)
{
	ER	er;

	switch (pohdr->type) {
	  case TPA_LINK:
	  case TMA_LINK:
		er = tkse_GetRecInfo(pohdr->desc, offset, recsize,
				     block, entry_len, n_entry);
		break;
	  case TPA_SEIO:
	  case TMA_SEIO:
	  case TPA_PTR:
	  case TMA_PTR:
		er = 0;
		if (offset  != NULL) {
			*offset  = 0;
		}
		if (recsize != NULL) {
			*recsize = 0;
		}
		if (n_entry != NULL) {
			*n_entry = 0;
		}
		break;
	  default:
		er = E_PAR;
		break;
	}

	return er;
}