+/* vim: set noexpandtab tabstop=4 shiftwidth=4:
+ *----------------------------------------------------------------------------
+ * emufs
+ *----------------------------------------------------------------------------
+ * This file is part of emufs.
+ *
+ * emufs 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.
+ *
+ * emufs 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 emufs; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA 02111-1307 USA
+ *----------------------------------------------------------------------------
+ * Creado: vie abr 9 16:17:50 ART 2004
+ * Autores: Nicolás Dimov <sagardua@uolsinectis.com.ar>
+ * Leandro Lucarella <llucare@fi.uba.ar>
+ *----------------------------------------------------------------------------
+ *
+ * $Id$
+ *
+ */
+
+/** \file
+ *
+ * Archivo para administrar el espacio libre disponible.
+ *
+ * Implementación del archivo para administrar el espacio libre disponible.
+ *
+ */
+
#include "fsc.h"
-#include "tipo3.h"
+#include <string.h>
+#include <unistd.h>
+
+/* Crea un archivo de Gaps o Espacio Libre en Bloque */
+int emufs_fsc_crear(EMUFS* efs)
+{
+ return emufs_crear_archivo_auxiliar(efs->nombre, EMUFS_FSC_EXT);
+}
-int emufs_fsc_agregar(EMUFS *emu, int num_bloque, int fs)
+/* Agrega un registro al archivo de espacio libre en bloque. */
+int emufs_fsc_agregar(EMUFS *emu, EMUFS_BLOCK_ID marker, EMUFS_FREE freespace)
{
FILE *f_fsc;
- BLOCK_FREE_T reg;
+ EMUFS_FSC reg;
+ char name_f_fsc[255];
+
+ strcpy(name_f_fsc,emu->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+
+ /* Lo guardo en el archivo al final "a+"*/
+ if ( (f_fsc = fopen(name_f_fsc,"r+"))==NULL ) return -1;
+ /* lo busco.. si esta lo modifico y si no lo agrego */
+ fseek(f_fsc,0,SEEK_SET);
+ while ( !feof(f_fsc) ){
+ if ( fread(®,sizeof(EMUFS_FSC),1,f_fsc) != 1) continue;
+ if ( reg.marker == marker ){
+ fseek(f_fsc,-sizeof(EMUFS_FSC),SEEK_CUR);
+ reg.freespace = freespace;
+ fwrite(®,sizeof(EMUFS_FSC),1,f_fsc);
+ fclose(f_fsc);
+ return 0;
+ }
+ }
+ /* Cargo el registro */
+ reg.marker = marker;
+ reg.freespace = freespace;
+ fwrite(®,sizeof(EMUFS_FSC),1,f_fsc);
+ fclose(f_fsc);
+ return 0;
+}
+
+/* Agrega un GAP en el archivo de Gaps para Filetype 2 */
+int emufs_fsc_agregar_gap(EMUFS *emu, EMUFS_OFFSET marker, EMUFS_FREE freespace)
+{
+ FILE *f_fsc;
+ EMUFS_FSC gap_aux,gap_before,gap_after,gap_new;
char name_f_fsc[255];
+ EMUFS_REG_ID pos_gap_before = 0, pos_gap_after = 0;
+ unsigned long source,destination,file_size,reg_count = 0,cant_moved = 0;
+
+ strcpy(name_f_fsc,emu->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+
+ gap_before.marker = -1;
+ gap_after.marker = -1;
+
+ /* Busco si hay un GAP por delante y/o por detras del que se esta por crear */
+ /* para en dicho caso realizar un merge! */
+ if ( (f_fsc = fopen(name_f_fsc,"r+")) == NULL) return -1;
+ while ( !feof(f_fsc) ){
+ if ( fread(&gap_aux,sizeof(EMUFS_FSC),1,f_fsc) != 1) continue;
+
+ /* Chequeo si es un gap justo anterior al nuestro */
+ if (gap_aux.marker+gap_aux.freespace == marker) {
+ gap_before.marker = gap_aux.marker;
+ gap_before.freespace = gap_aux.freespace;
+ pos_gap_before = reg_count;
+ }
+
+ /* Chequeo si es un gap justo posterior al nuestro */
+ if (gap_aux.marker == marker+freespace) {
+ gap_after.marker = gap_aux.marker;
+ gap_after.freespace = gap_aux.freespace;
+ pos_gap_after = reg_count;
+ }
+ reg_count += 1;
+ }
+
+ /* Si no encontre gaps ni por delante ni por detras */
+ if ((gap_before.marker == -1) && (gap_after.marker == -1)) {
+ /* Lo guardo en el archivo al final */
+ gap_new.marker = marker;
+ gap_new.freespace = freespace;
+ fseek(f_fsc,0,SEEK_END);
+ fwrite(&gap_new,sizeof(EMUFS_FSC),1,f_fsc);
+ fclose(f_fsc);
+ }
+ /* Si encuentro un GAP Justo por delante pero no por detras */
+ if ((gap_before.marker != -1) && (gap_after.marker == -1))
+ {
+ /* Me posiciono en el registro que indica dicho gap y lo reescribo con */
+ /* la suma de los espacios libres */
+ fseek(f_fsc,sizeof(EMUFS_FSC)*pos_gap_before,0);
+ gap_new.marker = gap_before.marker;
+ gap_new.freespace = gap_before.freespace + freespace;
+ fwrite(&gap_new,sizeof(EMUFS_FSC),1,f_fsc);
+ fclose(f_fsc);
+ }
+
+ /* Si encuentro un GAP Justo por detras pero no por delante */
+ if ((gap_before.marker == -1) && (gap_after.marker != -1))
+ {
+ /* Me posiciono en el registro que indica dicho gap y lo reescribo con */
+ /* los datos actualizados de offset y espacio */
+ fseek(f_fsc,sizeof(EMUFS_FSC)*pos_gap_after,0);
+ gap_new.marker = gap_after.marker - freespace;
+ gap_new.freespace = gap_after.freespace + freespace;
+ fwrite(&gap_new,sizeof(EMUFS_FSC),1,f_fsc);
+ fclose(f_fsc);
+ }
+
+ /* Finalmente, si encuentro Justo por delante y por detras..*/
+ if ((gap_before.marker != -1) && (gap_after.marker != -1))
+ {
+ /* Guardo el nuevo GAP que posee los tres espacios sumados */
+ if (pos_gap_before < pos_gap_after) {
+ fseek(f_fsc,sizeof(EMUFS_FSC)*pos_gap_before,0);
+ destination = sizeof(EMUFS_FSC)*pos_gap_after;
+ }
+ else {
+ fseek(f_fsc,sizeof(EMUFS_FSC)*pos_gap_after,0);
+ destination = sizeof(EMUFS_FSC)*pos_gap_before;
+ }
+ gap_new.marker = gap_before.marker;
+ gap_new.freespace = gap_before.freespace + freespace + gap_after.freespace;
+ fwrite(&gap_new,sizeof(EMUFS_FSC),1,f_fsc);
+
+ /* Preparo el escenario para la movida de registros */
+ source = destination+sizeof(EMUFS_FSC); /* Salteo el gap que elimino! */
+ fseek(f_fsc,0,SEEK_END);
+ file_size = ftell(f_fsc);
+ reg_count = (file_size - source) / sizeof(EMUFS_FSC);
+
+ /* Comienzo a mover */
+ while (cant_moved < reg_count) {
+ fseek(f_fsc,source,0);
+ fread(&gap_new,sizeof(EMUFS_FSC),1,f_fsc);
+ fseek(f_fsc,-sizeof(EMUFS_FSC)*2,SEEK_CUR);
+ fwrite(&gap_new,sizeof(EMUFS_FSC),1,f_fsc);
+ source += sizeof(EMUFS_FSC);
+ ++cant_moved;
+ }
+ fclose(f_fsc);
+ truncate(name_f_fsc, file_size - sizeof(EMUFS_FSC));
+ }
+
+ return 0;
+}
+
+/* Elimina un registro GAP del archivo de espacios libres (gaps) */
+int emufs_fsc_remove_gap(EMUFS *emu, EMUFS_OFFSET marker)
+{
+ FILE *f_fsc;
+ EMUFS_FSC gap_aux;
+ char name_f_fsc[255];
+ unsigned long source,destination,file_size,reg_count = 0,cant_moved = 0;
+
strcpy(name_f_fsc,emu->nombre);
- strcat(name_f_fsc,".fsc");
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
- /*cargo el registro*/
- reg.block = num_bloque; /*no incremento cant, porque grabe el nuevo bloque antes y no lo conte!!*/
- reg.free_space = fs;
- /*lo guardo en el archivo al final "a+"*/
- if ( (f_fsc = fopen(name_f_fsc,"a+"))==NULL ) return -1;
- fwrite(®,sizeof(BLOCK_FREE_T),1,f_fsc);
+ /* Busco el Gap en el .fsc */
+ if ((f_fsc = fopen(name_f_fsc,"r+")) == NULL) return -1;
+ while ( !feof(f_fsc) ){
+ if ( fread(&gap_aux,sizeof(EMUFS_FSC),1,f_fsc) != 1) continue;
+ if ( gap_aux.marker == marker ) break;
+ }
+
+ /* Preparo el escenario para la movida de registros */
+ fseek(f_fsc,-sizeof(EMUFS_FSC),SEEK_CUR);
+ destination = ftell(f_fsc);
+ source = destination+sizeof(EMUFS_FSC); /* Salteo el gap a eliminar! */
+ fseek(f_fsc,0,SEEK_END);
+ file_size = ftell(f_fsc);
+ reg_count = (file_size - source) / sizeof(EMUFS_FSC);
+
+ /* Comienzo a mover */
+ while (cant_moved < reg_count) {
+ fseek(f_fsc,source,0);
+ fread(&gap_aux,sizeof(EMUFS_FSC),1,f_fsc);
+ fseek(f_fsc,-sizeof(EMUFS_FSC)*2,SEEK_CUR);
+ fwrite(&gap_aux,sizeof(EMUFS_FSC),1,f_fsc);
+ source += sizeof(EMUFS_FSC);
+ ++cant_moved;
+ }
+ fclose(f_fsc);
+ truncate(name_f_fsc, file_size - sizeof(EMUFS_FSC));
+
+ return 0;
+}
+
+/* Objetivo: Actualiza un registro de espacio libre de acorde al FType */
+int emufs_fsc_actualizar(EMUFS *emu, EMUFS_BLOCK_ID marker, EMUFS_FREE freespace)
+{
+ FILE *f_fsc;
+ EMUFS_FSC reg;
+ char name_f_fsc[255];
+
+ strcpy(name_f_fsc,emu->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+
+ /*busco el bloque o gap que modifique*/
+ if ( (f_fsc = fopen(name_f_fsc,"r+")) == NULL) return -1;
+ while ( !feof(f_fsc) ){
+ if ( fread(®,sizeof(EMUFS_FSC),1,f_fsc) != 1) continue;
+ if ( reg.marker == marker ){
+ reg.freespace = freespace;
+ fseek(f_fsc,-sizeof(EMUFS_FSC),SEEK_CUR);
+ fwrite(®,sizeof(EMUFS_FSC),1,f_fsc);
+ break;
+ }
+ }
fclose(f_fsc);
return 0;
}
-int emufs_fsc_actualizar(EMUFS *emu, int num_bloque, int fs)
+/* Actualiza un registro de gap, en el archivo de Gaps en Disco */
+int emufs_fsc_actualizar_gap(EMUFS *emu, EMUFS_OFFSET marker, EMUFS_FREE freespace)
{
FILE *f_fsc;
- BLOCK_FREE_T reg;
+ EMUFS_FSC gap_aux;
char name_f_fsc[255];
strcpy(name_f_fsc,emu->nombre);
- strcat(name_f_fsc,".fsc");
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
- /*busco el bloque que modifique*/
+ /*busco el bloque o gap que modifique*/
if ( (f_fsc = fopen(name_f_fsc,"r+")) == NULL) return -1;
while ( !feof(f_fsc) ){
- if ( fread(®,sizeof(BLOCK_FREE_T),1,f_fsc) != 1) continue;
- if ( reg.block == num_bloque ){
- reg.free_space -= fs;
- fseek(f_fsc,-sizeof(BLOCK_FREE_T),SEEK_CUR);
- fwrite(®,sizeof(BLOCK_FREE_T),1,f_fsc);
+ if ( fread(&gap_aux,sizeof(EMUFS_FSC),1,f_fsc) != 1) continue;
+ if ( gap_aux.marker == marker ){
+ gap_aux.marker = marker + gap_aux.freespace - freespace;
+ gap_aux.freespace = freespace;
+ fseek(f_fsc,-sizeof(EMUFS_FSC),SEEK_CUR);
+ fwrite(&gap_aux,sizeof(EMUFS_FSC),1,f_fsc);
break;
}
}
fclose(f_fsc);
return 0;
}
+
+/* Me devuelve el ID del bloque u Offset del Gap donde quepa un registro, y guarda en n_freespace el espacio libre actualizado */
+EMUFS_BLOCK_ID emufs_fsc_buscar_lugar(EMUFS *emu, EMUFS_FREE reg_size, EMUFS_FREE *freespace)
+{
+ FILE *f_fsc;
+ EMUFS_FSC reg;
+ char name_f_fsc[255];
+ char found = 0;
+
+ strcpy(name_f_fsc,emu->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+
+ if ( (f_fsc = fopen(name_f_fsc,"r"))==NULL ) return EMUFS_NOT_FOUND;
+
+ if ( emu->tam_reg > emu->tam_bloque-sizeof(EMUFS_REG_ID) ){
+ fseek(f_fsc,0,SEEK_SET);
+ while(!feof(f_fsc)){
+ if (fread(®,sizeof(EMUFS_FSC),1,f_fsc) != 1) continue;
+ if (reg.freespace == emu->tam_bloque) {
+ fclose(f_fsc);
+ *freespace = reg.freespace;
+ return reg.marker;
+ }
+ }
+ }
+ /* Inicializamos la estructura para devolver algun valor en concreto */
+ /* en caso de que no se halle un espacio libre apropiado */
+ while(!feof(f_fsc)){
+ if (fread(®,sizeof(EMUFS_FSC),1,f_fsc) != 1) continue;
+ if (reg.freespace >= reg_size) {
+ found = 1;
+ break;
+ }
+ }
+
+ /* Si salio por error o por fin de archivo y no encontro space... */
+ if (!found) {
+ reg.marker = EMUFS_NOT_FOUND;
+ *freespace = emu->tam_bloque;
+ }
+ else *freespace = reg.freespace;
+
+ fclose(f_fsc);
+ return reg.marker;
+}
+
+/* Devuelve el espacio libre de un Bloque o Gap dado */
+EMUFS_FREE emufs_fsc_get_fs(EMUFS *emu, EMUFS_BLOCK_ID marker)
+{
+ FILE *f_fsc;
+ EMUFS_FSC reg;
+ char name_f_fsc[255];
+
+ strcpy(name_f_fsc,emu->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+
+ /* Busco el Bloque o Gap pedido y obtengo su espacio libre */
+ if ( (f_fsc = fopen(name_f_fsc,"r"))==NULL ) return -1;
+ while ( !feof(f_fsc) ){
+ if ( fread(®,sizeof(EMUFS_FSC),1,f_fsc) != 1 ) continue;
+ if ( reg.marker == marker )
+ break;
+ }
+
+ fclose(f_fsc);
+ return reg.freespace;
+}
+
+EMUFS_FREE emufs_fsc_get_total_fs(EMUFS *emu)
+{
+ FILE *f_fsc;
+ EMUFS_FSC reg;
+ char name_f_fsc[255];
+ EMUFS_FREE total;
+
+ strcpy(name_f_fsc,emu->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+
+ if ( (f_fsc = fopen(name_f_fsc,"r"))==NULL ) return -1;
+ total = 0;
+ while ( !feof(f_fsc) ){
+ if ( fread(®, sizeof(EMUFS_FSC), 1, f_fsc) != 1) continue;
+ total += reg.freespace;
+ }
+ fclose(f_fsc);
+ return total;
+}
+
+int emufs_fsc_get_max_min_fs(EMUFS *emu, EMUFS_FREE *min, EMUFS_FREE *max)
+{
+ FILE *f_fsc;
+ EMUFS_FSC reg;
+ char name_f_fsc[255];
+
+ strcpy(name_f_fsc,emu->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+
+ if ( (f_fsc = fopen(name_f_fsc,"r"))==NULL ) return -1;
+
+ /* Si el file esta vacio, devuelvo valores nulos */
+ fseek(f_fsc,0,SEEK_END);
+ if (ftell(f_fsc) == 0) {
+ *min = 0;
+ *max = 0;
+ return 0;
+ }
+ else
+ {
+ /* Busco Min y Max */
+ *min = ULONG_MAX;
+ *max = 0;
+ fseek(f_fsc,0,SEEK_SET);
+ while ( !feof(f_fsc) ){
+ if ( fread(®, sizeof(EMUFS_FSC), 1, f_fsc) != 1) continue;
+ if ( reg.freespace < *min )
+ *min = reg.freespace;
+ if ( reg.freespace > *max )
+ *max = reg.freespace;
+ }
+ fclose(f_fsc);
+ return 0;
+ }
+}
+
+EMUFS_FREE emufs_fsc_get_media_fs(EMUFS *emu)
+{
+ FILE *f_fsc;
+ EMUFS_FSC reg;
+ char name_f_fsc[255];
+ EMUFS_FREE total_fs = 0;
+ EMUFS_REG_ID gap_count = 0;
+
+ strcpy(name_f_fsc,emu->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+
+ if ( (f_fsc = fopen(name_f_fsc,"r"))==NULL ) return -1;
+
+ while ( !feof(f_fsc) ){
+ if ( fread(®, sizeof(EMUFS_FSC), 1, f_fsc) != 1) continue;
+ total_fs += reg.freespace;
+ ++gap_count;
+ }
+
+ fclose(f_fsc);
+
+ if (gap_count > 0) return total_fs/gap_count;
+ else return 0;
+}
+
+int emufs_fsc_get_cant_bloques_vacios(EMUFS *emu)
+{
+ FILE *f_fsc;
+ EMUFS_FSC reg;
+ char name_f_fsc[255];
+ int cant=0;
+
+ strcpy(name_f_fsc,emu->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+
+ if ( (f_fsc = fopen(name_f_fsc,"r"))==NULL ) return -1;
+ while ( !feof(f_fsc) ){
+ fread(®, sizeof(EMUFS_FSC), 1, f_fsc);
+ if ( reg.freespace == emu->tam_bloque )
+ cant++;
+ }
+
+ fclose(f_fsc);
+ return cant;
+}
+
+int emufs_fsc_truncate(EMUFS* efs, EMUFS_BLOCK_ID blocks)
+{
+ char name_f_fsc[255];
+
+ strcpy(name_f_fsc, efs->nombre);
+ strcat(name_f_fsc, EMUFS_FSC_EXT);
+ return truncate(name_f_fsc, blocks * sizeof(EMUFS_FSC));
+}
projects / z.facultad / 75.06 / emufs.git / blobdiff