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Diffstat (limited to 'libibex/diskarray.c')
-rw-r--r-- | libibex/diskarray.c | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/libibex/diskarray.c b/libibex/diskarray.c new file mode 100644 index 0000000000..2664e0f6b5 --- /dev/null +++ b/libibex/diskarray.c @@ -0,0 +1,255 @@ +/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- + * + * Copyright (C) 2000 Helix Code, Inc. + * + * Authors: Michael Zucchi <notzed@helixcode.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU Library General Public License + * as published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This library 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 + * Library General Public License for more details. + * + * You should have received a copy of the GNU Library General Public + * License along with the Gnome Library; see the file COPYING.LIB. If not, + * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ + +/* a disk based array storage class */ + + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> + +#include <glib.h> + +#include "block.h" +#include "index.h" + +#define d(x) +/*#define DEBUG*/ + +static struct _IBEXStore *disk_create(struct _memcache *bc); +static int disk_sync(struct _IBEXStore *store); +static int disk_close(struct _IBEXStore *store); + +static blockid_t disk_add(struct _IBEXStore *store, blockid_t head, nameid_t data); +static blockid_t disk_add_list(struct _IBEXStore *store, blockid_t head, GArray *data); +static blockid_t disk_remove(struct _IBEXStore *store, blockid_t head, nameid_t data); +static void disk_free(struct _IBEXStore *store, blockid_t head); + +static gboolean disk_find(struct _IBEXStore *store, blockid_t head, nameid_t data); +static GArray *disk_get(struct _IBEXStore *store, blockid_t head); + +struct _IBEXStoreClass ibex_diskarray_class = { + disk_create, disk_sync, disk_close, + disk_add, disk_add_list, + disk_remove, disk_free, + disk_find, disk_get +}; + +static struct _IBEXStore *disk_create(struct _memcache *bc) +{ + struct _IBEXStore *store; + + store = g_malloc0(sizeof(*store)); + store->klass = &ibex_diskarray_class; + store->blocks = bc; + + return store; +} + +static int disk_sync(struct _IBEXStore *store) +{ + /* no cache, nop */ + return 0; +} + +static int disk_close(struct _IBEXStore *store) +{ + g_free(store); + return 0; +} + +static blockid_t +disk_add(struct _IBEXStore *store, blockid_t head, nameid_t data) +{ + struct _block *block; + struct _block *newblock; + blockid_t new; + + if (head == 0) { + head = ibex_block_get(store->blocks); + } + block = ibex_block_read(store->blocks, head); + + d(printf("adding record %d to block %d (next = %d)\n", data, head, block->next)); + + if (block->used < sizeof(block->bl_data)/sizeof(block->bl_data[0])) { + d(printf("adding record into block %d %d\n", head, data)); + block->bl_data[block->used] = data; + block->used++; + ibex_block_dirty(block); + return head; + } else { + new = ibex_block_get(store->blocks); + newblock = ibex_block_read(store->blocks, new); + newblock->next = head; + newblock->bl_data[0] = data; + newblock->used = 1; + d(printf("adding record into new %d %d, next =%d\n", new, data, newblock->next)); + ibex_block_dirty(newblock); + return new; + } +} + +static blockid_t +disk_add_list(struct _IBEXStore *store, blockid_t head, GArray *data) +{ + struct _block *block; + struct _block *newblock; + blockid_t new; + int copied = 0; + int left, space, tocopy; + + if (head == 0) { + head = ibex_block_get(store->blocks); + } + block = ibex_block_read(store->blocks, head); + + while (copied < data->len) { + left = data->len - copied; + space = sizeof(block->bl_data)/sizeof(block->bl_data[0]) - block->used; + if (space) { + tocopy = MIN(left, space); + memcpy(block->bl_data+block->used, &g_array_index(data, blockid_t, copied), tocopy*sizeof(blockid_t)); + block->used += tocopy; + ibex_block_dirty(block); + } else { + new = ibex_block_get(store->blocks); + newblock = ibex_block_read(store->blocks, new); + newblock->next = head; + tocopy = MIN(left, sizeof(block->bl_data)/sizeof(block->bl_data[0])); + memcpy(newblock->bl_data, &g_array_index(data, blockid_t, copied), tocopy*sizeof(blockid_t)); + newblock->used = tocopy; + block = newblock; + head = new; + ibex_block_dirty(newblock); + } + copied += tocopy; + } + return head; +} + +static blockid_t +disk_remove(struct _IBEXStore *store, blockid_t head, nameid_t data) +{ + blockid_t node = head; + + d(printf("removing %d from %d\n", data, head)); + while (node) { + struct _block *block = ibex_block_read(store->blocks, node); + int i; + + for (i=0;i<block->used;i++) { + if (block->bl_data[i] == data) { + struct _block *start = ibex_block_read(store->blocks, head); + + start->used--; + block->bl_data[i] = start->bl_data[start->used]; + if (start->used == 0) { + struct _root *root = (struct _root *)ibex_block_read(store->blocks, 0); + blockid_t new; + + d(printf("dropping block %d, new head = %d\n", head, start->next)); + new = start->next; + start->next = root->free; + root->free = head; + head = new; + ibex_block_dirty((struct _block *)root); + } + ibex_block_dirty(block); + ibex_block_dirty(start); + return head; + } + } + node = block->next; + } + return head; +} + +static void disk_free(struct _IBEXStore *store, blockid_t head) +{ + blockid_t next; + struct _block *block; + + while (head) { + block = ibex_block_read(store->blocks, head); + next = block->next; + ibex_block_free(store->blocks, head); + head = next; + } +} + +static gboolean +disk_find(struct _IBEXStore *store, blockid_t head, nameid_t data) +{ + blockid_t node = head; + + d(printf("finding %d from %d\n", data, head)); + while (node) { + struct _block *block = ibex_block_read(store->blocks, node); + int i; + + for (i=0;i<block->used;i++) { + if (block->bl_data[i] == data) { + return TRUE; + } + } + node = block->next; + } + return FALSE; +} + +static GArray * +disk_get(struct _IBEXStore *store, blockid_t head) +{ + GArray *result = g_array_new(0, 0, sizeof(nameid_t)); + + while (head) { + struct _block *block = ibex_block_read(store->blocks, head); + + d(printf("getting data from block %d\n", head)); + + g_array_append_vals(result, block->bl_data, block->used); + head = block->next; + d(printf("next = %d\n", head)); + } + return result; +} + +void +ibex_diskarray_dump(struct _memcache *blocks, blockid_t head) +{ + blockid_t node = head; + + printf("dumping list %d\n", node); + while (node) { + struct _block *block = ibex_block_read(blocks, node); + int i; + + printf(" block %d used %d\n ", node, block->used); + for (i=0;i<block->used;i++) { + printf(" %d", block->bl_data[i]); + } + printf("\n"); + node = block->next; + } +} |