lsm/mdbtools
1
0
Fork 0
mirror of https://github.com/mdbtools/mdbtools.git synced 2025-04-05 20:31:00 +08:00
Code Issues Actions Packages Projects Releases Wiki Activity

Make better use of read_pg_if_n

Browse Source
This commit is contained in:
whydoubt 2004-06-14 12:13:25 +00:00
parent 2a6d21ce6d
commit 2dd710e5c4
2 changed files with 54 additions and 100 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
ChangeLog
View File

@ -1,3 +1,6 @@
Mon Jun 14 07:12:37 CDT 2004 Jeff Smith <whydoubt@yahoo.com>
* src/libmdb/table.c: Make better use of read_pg_if_n
Fri Jun 11 16:56:06 CDT 200 Jeff Smith <whydoubt@yahoo.com>
* src/libmdb/table.c: Fix bug in read_pg_if_n

151
src/libmdb/table.c
View File

@ -159,16 +159,16 @@ GPtrArray *mdb_read_columns(MdbTableDef *table)
{
MdbHandle *mdb = table->entry->mdb;
MdbFormatConstants *fmt = mdb->fmt;
MdbColumn col, *pcol;
int len, i,j;
unsigned char low_byte, high_byte;
int cur_col, cur_name;
int name_sz;
MdbColumn *pcol;
unsigned char *col;
int i, cur_pos, name_sz;
GSList *slist = NULL;
table->columns = g_ptr_array_new();
cur_col = fmt->tab_cols_start_offset +
col = (unsigned char *) g_malloc(fmt->tab_col_entry_size);
cur_pos = fmt->tab_cols_start_offset +
(table->num_real_idxs * fmt->tab_ridx_entry_size);
/* new code based on patch submitted by Tim Nelson 2000.09.27 */
@ -179,67 +179,52 @@ GPtrArray *mdb_read_columns(MdbTableDef *table)
for (i=0;i<table->num_cols;i++) {
#ifdef MDB_DEBUG
/* printf("column %d\n", i);
buffer_dump(mdb->pg_buf, cur_col ,cur_col + 18); */
buffer_dump(mdb->pg_buf, cur_pos ,cur_pos + 18); */
#endif
memset(&col, 0, sizeof(col));
read_pg_if_n(mdb, col, &cur_pos, fmt->tab_col_entry_size);
cur_pos += fmt->tab_col_entry_size;
pcol = (MdbColumn *) g_malloc0(sizeof(MdbColumn));
read_pg_if(mdb, &cur_col, 0);
col.col_type = mdb->pg_buf[cur_col];
pcol->col_type = col[0];
read_pg_if(mdb, &cur_col, fmt->col_num_offset); // col_num_offset == 1 or 5
col.col_num = mdb->pg_buf[cur_col + fmt->col_num_offset];
// col_num_offset == 1 or 5
pcol->col_num = col[fmt->col_num_offset];
//fprintf(stdout,"----- column %d -----\n",col.col_num);
read_pg_if(mdb, &cur_col, fmt->tab_col_offset_var); // col_var == 3 or 7
low_byte = mdb->pg_buf[cur_col + fmt->tab_col_offset_var];
read_pg_if(mdb, &cur_col, fmt->tab_col_offset_var + 1);
high_byte = mdb->pg_buf[cur_col + fmt->tab_col_offset_var + 1];
col.var_col_num = high_byte * 256 + low_byte;
//fprintf(stdout,"var column pos %d\n",col.var_col_num);
//fprintf(stdout,"----- column %d -----\n",pcol->col_num);
// col_var == 3 or 7
pcol->var_col_num = mdb_get_int16(col, fmt->tab_col_offset_var);
//fprintf(stdout,"var column pos %d\n",pcol->var_col_num);
read_pg_if(mdb, &cur_col, fmt->tab_row_col_num_offset); // col_var == 5 or 9
low_byte = mdb->pg_buf[cur_col + fmt->tab_row_col_num_offset];
read_pg_if(mdb, &cur_col, fmt->tab_row_col_num_offset + 1);
high_byte = mdb->pg_buf[cur_col + fmt->tab_row_col_num_offset + 1];
col.row_col_num = high_byte * 256 + low_byte;
//fprintf(stdout,"row column num %d\n",col.row_col_num);
// col_var == 5 or 9
pcol->row_col_num = mdb_get_int16(col, fmt->tab_row_col_num_offset);
//fprintf(stdout,"row column num %d\n",pcol->row_col_num);
/* FIXME: can this be right in Jet3 and Jet4? */
if (col.col_type == MDB_NUMERIC) {
read_pg_if(mdb, &cur_col, 11);
col.col_prec = mdb->pg_buf[cur_col + 11];
read_pg_if(mdb, &cur_col, 12);
col.col_scale = mdb->pg_buf[cur_col + 12];
if (pcol->col_type == MDB_NUMERIC) {
pcol->col_prec = col[11];
pcol->col_scale = col[12];
}
read_pg_if(mdb, &cur_col, fmt->col_fixed_offset); // col_fixed_offset == 13 or 15
col.is_fixed = mdb->pg_buf[cur_col + fmt->col_fixed_offset] &
0x01 ? 1 : 0;
// col_fixed_offset == 13 or 15
pcol->is_fixed = col[fmt->col_fixed_offset] & 0x01 ? 1 : 0;
read_pg_if(mdb, &cur_col, fmt->tab_col_offset_fixed); // col_fixed_offset == 13 or 15
low_byte = mdb->pg_buf[cur_col + fmt->tab_col_offset_fixed];
read_pg_if(mdb, &cur_col, fmt->tab_col_offset_fixed + 1);
high_byte = mdb->pg_buf[cur_col + fmt->tab_col_offset_fixed + 1];
col.fixed_offset = high_byte * 256 + low_byte;
//fprintf(stdout,"fixed column offset %d\n",col.fixed_offset);
//fprintf(stdout,"col type %s\n",col.is_fixed ? "fixed" : "variable");
// col_fixed_offset == 13 or 15
pcol->fixed_offset = mdb_get_int16(col, fmt->tab_col_offset_fixed);
//fprintf(stdout,"fixed column offset %d\n",pcol->fixed_offset);
//fprintf(stdout,"col type %s\n",pcol->is_fixed ? "fixed" : "variable");
if (col.col_type != MDB_BOOL) {
read_pg_if(mdb, &cur_col, fmt->col_size_offset); // col_size_offset == 16 or 23
low_byte = mdb->pg_buf[cur_col + fmt->col_size_offset];
read_pg_if(mdb, &cur_col, fmt->col_size_offset + 1);
high_byte = mdb->pg_buf[cur_col + fmt->col_size_offset + 1];
col.col_size += high_byte * 256 + low_byte;
} else
col.col_size=0;
if (pcol->col_type != MDB_BOOL) {
// col_size_offset == 16 or 23
pcol->col_size = mdb_get_int16(col, fmt->col_size_offset);
} else {
pcol->col_size=0;
}
pcol = g_memdup(&col, sizeof(MdbColumn));
slist = g_slist_insert_sorted(slist,pcol,(GCompareFunc)mdb_col_comparer);
cur_col += fmt->tab_col_entry_size;
}
cur_name = cur_col;
g_free (col);
/*
** column names
*/
@ -247,56 +232,22 @@ GPtrArray *mdb_read_columns(MdbTableDef *table)
/* fetch the column */
pcol = g_slist_nth_data (slist, i);
/* we have reached the end of page */
read_pg_if(mdb, &cur_name, 0);
name_sz = mdb->pg_buf[cur_name];
if (IS_JET4(mdb)) {
/* FIX ME - for now just skip the high order byte */
cur_name += 2;
/* determine amount of name on this page */
len = ((cur_name + name_sz) > fmt->pg_size) ?
fmt->pg_size - cur_name :
name_sz;
/* strip high order (second) byte from unicode string */
for (j=0;j<len;j+=2) {
pcol->name[j/2] = mdb->pg_buf[cur_name + j];
}
/* name wrapped over page */
if (len < name_sz) {
/* read the next pg */
mdb_read_pg(mdb, mdb_pg_get_int32(mdb,4));
cur_name = 8 - (fmt->pg_size - cur_name);
/* get the rest of the name */
for (j=len;j<name_sz;j++) {
if (!(j%2))
pcol->name[j/2] = mdb->pg_buf[cur_name + j];
}
}
pcol->name[name_sz/2]='\0';
cur_name += name_sz;
char *tmp_buf;
name_sz = read_pg_if_16(mdb, &cur_pos);
cur_pos += 2;
tmp_buf = (char *) g_malloc(name_sz);
read_pg_if_n(mdb, tmp_buf, &cur_pos, name_sz);
mdb_unicode2ascii(mdb, tmp_buf, 0, name_sz, pcol->name);
g_free(tmp_buf);
cur_pos += name_sz;
} else if (IS_JET3(mdb)) {
/* determine amount of name on this page */
len = ((cur_name + name_sz) > fmt->pg_size) ?
fmt->pg_size - cur_name :
name_sz;
if (len) {
memcpy(pcol->name, &mdb->pg_buf[cur_name+1], len);
}
/* name wrapped over page */
if (len < name_sz) {
/* read the next pg */
mdb_read_pg(mdb, mdb_pg_get_int32(mdb,4));
cur_name = 8 - (fmt->pg_size - cur_name);
/* get the rest of the name */
memcpy(&pcol->name[len], &mdb->pg_buf[cur_name], name_sz - len);
}
read_pg_if(mdb, &cur_pos, 0);
name_sz = mdb->pg_buf[cur_pos];
cur_pos++;
read_pg_if_n(mdb, pcol->name, &cur_pos, name_sz);
pcol->name[name_sz]='\0';
cur_name += name_sz + 1;
cur_pos += name_sz;
} else {
fprintf(stderr,"Unknown MDB version\n");
}
@ -309,7 +260,7 @@ GPtrArray *mdb_read_columns(MdbTableDef *table)
g_slist_free(slist);
table->index_start = cur_name;
table->index_start = cur_pos;
return table->columns;
}