/**
* mdb_find_pg_row
* @mdb: Database file handle
* @pg_row: Lower byte contains the row number, the upper three contain page
* @buf: Pointer for returning a pointer to the page
* @off: Pointer for returning an offset to the row
* @len: Pointer for returning the length of the row
*
* Returns: 0 on success. 1 on failure.
*/
int mdb_find_pg_row(MdbHandle *mdb, int pg_row, void **buf, int *off, size_t *len)
{
unsigned int pg = pg_row >> 8;
unsigned int row = pg_row & 0xff;
if (mdb_read_alt_pg(mdb, pg) != mdb->fmt->pg_size)
return 1;
mdb_swap_pgbuf(mdb);
mdb_find_row(mdb, row, off, len);
mdb_swap_pgbuf(mdb);
*buf = mdb->alt_pg_buf;
return 0;
}
static gint32
mdb_map_find_next1(MdbHandle *mdb, unsigned char *map, unsigned int map_sz, guint32 start_pg)
{
guint32 map_ind, max_map_pgs, offset, usage_bitlen;
/*
* start_pg will tell us where to (re)start the scan
* for the next data page. each usage_map entry points to a
* 0x05 page which bitmaps (mdb->fmt->pg_size - 4) * 8 pages.
*
* map_ind gives us the starting usage_map entry
* offset gives us a page offset into the bitmap
*/
usage_bitlen = (mdb->fmt->pg_size - 4) * 8;
max_map_pgs = (map_sz - 1) / 4;
map_ind = (start_pg + 1) / usage_bitlen;
offset = (start_pg + 1) % usage_bitlen;
for (; map_ind<max_map_pgs; map_ind++) {
unsigned char *usage_bitmap;
guint32 i, map_pg;
if (!(map_pg = mdb_get_int32(map, (map_ind*4)+1))) {
continue;
}
if(mdb_read_alt_pg(mdb, map_pg) != mdb->fmt->pg_size) {
mdb->fatal_error_handler("Oops! didn't get a full page at %d\n", map_pg);
exit(1);
}
usage_bitmap = mdb->alt_pg_buf + 4;
for (i=offset; i<usage_bitlen; i++) {
if (usage_bitmap[i/8] & (1 << (i%8))) {
return map_ind*usage_bitlen + i;
}
}
offset = 0;
}
/* didn't find anything */
return 0;
}
GPtrArray *
mdb_read_indices(MdbTableDef *table)
{
MdbCatalogEntry *entry = table->entry;
MdbHandle *mdb = entry->mdb;
MdbFormatConstants *fmt = mdb->fmt;
MdbIndex *pidx;
unsigned int i, j;
int idx_num, key_num, col_num;
int cur_pos, name_sz, idx2_sz, type_offset;
int index_start_pg = mdb->cur_pg;
guchar *tmpbuf;
table->indices = g_ptr_array_new();
if (IS_JET4(mdb)) {
cur_pos = table->index_start + 52 * table->num_real_idxs;
idx2_sz = 28;
type_offset = 23;
} else {
cur_pos = table->index_start + 39 * table->num_real_idxs;
idx2_sz = 20;
type_offset = 19;
}
tmpbuf = (guchar *) g_malloc(idx2_sz);
for (i=0;i<table->num_idxs;i++) {
read_pg_if_n(mdb, tmpbuf, &cur_pos, idx2_sz);
cur_pos += idx2_sz;
pidx = (MdbIndex *) g_malloc0(sizeof(MdbIndex));
pidx->table = table;
pidx->index_num = mdb_get_int16(tmpbuf, 4);
pidx->index_type = tmpbuf[type_offset];
g_ptr_array_add(table->indices, pidx);
}
g_free(tmpbuf);
for (i=0;i<table->num_idxs;i++) {
pidx = g_ptr_array_index (table->indices, i);
if (IS_JET4(mdb)) {
name_sz=read_pg_if_16(mdb, &cur_pos);
cur_pos += 2;
tmpbuf = g_malloc(name_sz);
read_pg_if_n(mdb, tmpbuf, &cur_pos, name_sz);
cur_pos += name_sz;
mdb_unicode2ascii(mdb, tmpbuf, 0, name_sz, pidx->name);
g_free(tmpbuf);
} else {
read_pg_if(mdb, &cur_pos, 0);
name_sz=mdb->pg_buf[cur_pos++];
read_pg_if_n(mdb, (unsigned char *) pidx->name, &cur_pos, name_sz);
cur_pos += name_sz;
pidx->name[name_sz]='\0';
}
//fprintf(stderr, "index name %s\n", pidx->name);
}
mdb_read_alt_pg(mdb, entry->table_pg);
mdb_read_pg(mdb, index_start_pg);
cur_pos = table->index_start;
idx_num=0;
for (i=0;i<table->num_real_idxs;i++) {
if (IS_JET4(mdb)) cur_pos += 4;
do {
pidx = g_ptr_array_index (table->indices, idx_num++);
} while (pidx && pidx->index_type==2);
/* if there are more real indexes than index entries left after
removing type 2's decrement real indexes and continue. Happens
on Northwind Orders table.
*/
if (!pidx) {
table->num_real_idxs--;
continue;
}
pidx->num_rows = mdb_get_int32(mdb->alt_pg_buf,
fmt->tab_cols_start_offset +
(i*fmt->tab_ridx_entry_size));
key_num=0;
for (j=0;j<MDB_MAX_IDX_COLS;j++) {
col_num=read_pg_if_16(mdb,&cur_pos);
cur_pos += 2;
read_pg_if(mdb, &cur_pos, 0);
cur_pos++;
if (col_num == 0xFFFF)
continue;
/* set column number to a 1 based column number and store */
pidx->key_col_num[key_num] = col_num + 1;
pidx->key_col_order[key_num] =
(mdb->pg_buf[cur_pos-1]) ? MDB_ASC : MDB_DESC;
key_num++;
}
pidx->num_keys = key_num;
cur_pos += 4;
pidx->first_pg = read_pg_if_32(mdb, &cur_pos);
cur_pos += 4;
read_pg_if(mdb, &cur_pos, 0);
pidx->flags = mdb->pg_buf[cur_pos++];
if (IS_JET4(mdb)) cur_pos += 9;
}
return NULL;
}
