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fix reading of deleted/added columns

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brianb
2004-04-16 15:45:12 +00:00
parent 0baed7b268
commit bde195357e
3 changed files with 143 additions and 84 deletions
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5
ChangeLog
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@@ -1,3 +1,8 @@
Fri Apr 16 10:48:05 EDT 2004 Brian Bruns <brian@bruns.com>
* src/libmdb/write.c: restructuring of mdb_crack_row?() to accomodate
columns deletes/adds
* src/libmdb/index.c: fix stupid bug in mdb_swap_n()
Tue Apr 13 19:08:51 CDT 2004 Jeff Smith <whydoubt@yahoo.com>
* src/util/mdb-check.c: Make mdb-check compilable
* configure.in:

2
src/libmdb/index.c
View File

@@ -186,7 +186,7 @@ mdb_index_swap_n(unsigned char *src, int sz, unsigned char *dest)
{
int i, j = 0;
for (i = sz; i > 0; i++) {
for (i = sz; i > 0; i--) {
dest[j++] = src[i];
}
}

220
src/libmdb/write.c
View File

@@ -93,7 +93,7 @@ mdb_crack_row4(MdbTableDef *table, int row_start, int row_end, MdbField *fields)
MdbHandle *mdb = entry->mdb;
MdbColumn *col;
int i;
int var_cols = 0, fixed_cols = 0, num_cols;
int var_cols = 0, row_var_cols, fixed_cols = 0, row_fixed_cols, num_cols;
int var_cols_found, fixed_cols_found, var_entry_pos;
int col_start, next_col;
unsigned char *nullmask;
@@ -115,12 +115,12 @@ mdb_crack_row4(MdbTableDef *table, int row_start, int row_end, MdbField *fields)
for (i=0;i<table->num_cols;i++) {
col = g_ptr_array_index (table->columns, i);
row_pos = col->row_col_num;
row_pos = col->col_num;
byte_num = row_pos / 8;
bit_num = row_pos % 8;
/* logic on nulls is reverse, 1 is not null, 0 is null */
fields[i].is_null = nullmask[byte_num] & 1 << bit_num ? 0 : 1;
//printf("col %d is %s\n", i, fields[i].is_null ? "null" : "not null");
//printf("row_pos %d col %d is %s\n", row_pos, i, fields[i].is_null ? "null" : "not null");
}
/* fields are ordered fixed then variable */
@@ -141,6 +141,7 @@ mdb_crack_row4(MdbTableDef *table, int row_start, int row_end, MdbField *fields)
fields[i].is_fixed = 0;
}
}
row_var_cols = mdb_pg_get_int16(mdb, row_end - bitmask_sz - 1);
/* find the end of data pointer */
eod = mdb_pg_get_int16(mdb, row_end - 3 - var_cols*2 - bitmask_sz);
@@ -148,52 +149,57 @@ mdb_crack_row4(MdbTableDef *table, int row_start, int row_end, MdbField *fields)
/* actual cols on this row */
fixed_cols_found = 0;
var_cols_found = 0;
row_fixed_cols = num_cols - row_var_cols;
for (i=0;i<table->num_cols;i++) {
col = g_ptr_array_index(table->columns,i);
if (mdb_is_fixed_col(col) && fixed_cols_found <= fixed_cols) {
real_offset += col->col_size;
fields[i].start = row_start + col->fixed_offset + 2;
fields[i].value = &mdb->pg_buf[row_start + col->fixed_offset + 2];
if (mdb_is_fixed_col(col)) {
if (fixed_cols_found <= row_fixed_cols) {
real_offset += col->col_size;
fields[i].start = row_start + col->fixed_offset + 2;
fields[i].value = &mdb->pg_buf[row_start + col->fixed_offset + 2];
} else {
fields[i].start = 0;
fields[i].value = NULL;
fields[i].siz = 0;
fields[i].is_null = 1;
}
fixed_cols_found++;
}
}
/* loop through fixed columns and add values to fields[] */
/*
for (j=0;j<table->num_cols;j++) {
col = g_ptr_array_index(table->columns,j);
if (mdb_is_fixed_col(col) && ++fixed_cols_found <= fixed_cols) {
fields[totcols].start = row_start + col_start;
fields[totcols++].value = &mdb->pg_buf[row_start + col_start];
if (col->col_type != MDB_BOOL)
col_start += col->col_size;
}
}
*/
col_start = mdb_pg_get_int16(mdb, row_end - 3 - bitmask_sz);
for (i=0;i<table->num_cols;i++) {
col = g_ptr_array_index(table->columns,i);
if (!mdb_is_fixed_col(col) && ++var_cols_found <= var_cols) {
if (var_cols_found==var_cols) {
len=eod - col_start;
if (!mdb_is_fixed_col(col)) {
var_cols_found++;
if (var_cols_found <= row_var_cols) {
if (var_cols_found==row_var_cols) {
len=eod - col_start;
//printf("len = %d eod %d col_start %d\n",len, eod, col_start);
} else {
/* position of the var table
* entry for this column */
var_entry_pos =
row_end -
bitmask_sz -
var_cols_found * 2 - 2 - 1;
next_col = mdb_pg_get_int16(mdb, var_entry_pos);
len = next_col - col_start;
} /* if found==var_cols */
//printf("len = %d eod %d col_start %d\n",len, eod, col_start);
} else {
/* position of the var table
* entry for this column */
var_entry_pos =
row_end -
bitmask_sz -
var_cols_found * 2 - 2 - 1;
next_col = mdb_pg_get_int16(mdb, var_entry_pos);
len = next_col - col_start;
} /* if found==var_cols */
fields[i].start = row_start + col_start;
fields[i].value = &mdb->pg_buf[row_start +col_start];
fields[i].siz = len;
col_start += len;
//printf("is_null %d\n",fields[i].is_null);
fields[i].start = row_start + col_start;
fields[i].value = &mdb->pg_buf[row_start +col_start];
fields[i].siz = len;
col_start += len;
} else {
fields[i].start = 0;
fields[i].value = NULL;
fields[i].siz = 0;
fields[i].is_null = 1;
}
} /* if !fixed */
} /* for */
@@ -208,6 +214,7 @@ mdb_crack_row3(MdbTableDef *table, int row_start, int row_end, MdbField *fields)
MdbColumn *col;
int i;
int var_cols = 0, fixed_cols = 0, num_cols;
int row_var_cols = 0, row_fixed_cols = 0;
int var_cols_found, fixed_cols_found, var_entry_pos;
int col_start;
unsigned char *nullmask;
@@ -223,9 +230,9 @@ mdb_crack_row3(MdbTableDef *table, int row_start, int row_end, MdbField *fields)
num_cols = mdb->pg_buf[row_start];
if (num_cols != table->num_cols) {
fprintf(stderr,"WARNING: number of table columns does not match number of row columns, strange results may occur\n");
}
//if (num_cols != table->num_cols) {
//fprintf(stderr,"WARNING: number of table columns does not match number of row columns, strange results may occur\n");
//}
/* compute nulls first to help with fixed colnum's */
bitmask_sz = (num_cols - 1) / 8 + 1;
@@ -233,7 +240,7 @@ mdb_crack_row3(MdbTableDef *table, int row_start, int row_end, MdbField *fields)
for (i=0;i<table->num_cols;i++) {
col = g_ptr_array_index (table->columns, i);
row_pos = col->row_col_num;
row_pos = col->col_num;
byte_num = row_pos / 8;
bit_num = row_pos % 8;
/* logic on nulls is reverse, 1 is not null, 0 is null */
@@ -271,78 +278,125 @@ mdb_crack_row3(MdbTableDef *table, int row_start, int row_end, MdbField *fields)
fixed_cols_found = 0;
var_cols_found = 0;
/* loop through fixed columns and add values to fields[] */
for (i=0;i<table->num_cols;i++) {
col = g_ptr_array_index(table->columns,i);
if (mdb_is_fixed_col(col) && ++fixed_cols_found <= fixed_cols) {
fields[i].start = row_start + col_start;
fields[i].value = &mdb->pg_buf[row_start + col_start];
if (col->col_type != MDB_BOOL)
col_start += col->col_size;
}
}
/* if fixed columns add up to more than 256, we need a jump */
col_ptr = row_end - bitmask_sz - num_of_jumps - 1;
if (col_start >= 256) {
num_of_jumps++;
jumps_used++;
row_start = row_start + col_start - (col_start % 256);
}
col_start = row_start;
/* compute the number of jumps (row size - overhead) / 256
* but you have to include the jump table itself, thus
* the loop. */
col_start = row_start;
while (col_start+256 < row_end-bitmask_sz-1-var_cols-num_of_jumps){
col_start += 256;
num_of_jumps++;
}
col_ptr = row_end - bitmask_sz - num_of_jumps - 1;
if (mdb->pg_buf[col_ptr]==0xFF) {
col_ptr--;
}
row_var_cols = mdb->pg_buf[row_end - bitmask_sz - num_of_jumps];
row_fixed_cols = num_cols - row_var_cols;
if (mdb_get_option(MDB_DEBUG_ROW)) {
fprintf(stdout,"bitmask_sz %d num_of_jumps %d\n",bitmask_sz, num_of_jumps);
fprintf(stdout,"var_cols %d row_var_cols %d\n",var_cols, row_var_cols);
fprintf(stdout,"fixed_cols %d row_fixed_cols %d\n",fixed_cols, row_fixed_cols);
}
/* loop through fixed columns and add values to fields[] */
for (i=0;i<table->num_cols;i++) {
col = g_ptr_array_index(table->columns,i);
if (mdb_is_fixed_col(col)) {
if (fixed_cols_found <= row_fixed_cols) {
fields[i].start = row_start + col->fixed_offset + 1;
fields[i].value = &mdb->pg_buf[row_start + col->fixed_offset + 1];
if (col->col_type != MDB_BOOL)
col_start += col->col_size;
} else {
fields[i].start = 0;
fields[i].value = NULL;
fields[i].siz = 0;
fields[i].is_null = 1;
}
fixed_cols_found++;
}
}
/* col_start is now the offset to the first variable length field */
col_start = mdb->pg_buf[col_ptr];
//fprintf(stdout,"col_ptr %d col_start %d\n",col_ptr, col_start);
for (i=0;i<table->num_cols;i++) {
col = g_ptr_array_index(table->columns,i);
/* if it's a var_col and we aren't looking at a column
* added after this row was created */
if (!mdb_is_fixed_col(col) && ++var_cols_found <= var_cols) {
if (!mdb_is_fixed_col(col)) {
var_cols_found++;
if (var_cols_found <= row_var_cols) {
/* if the position of this var_col matches the number
* in the current jump table entry, then increment
* the jump_used and adjust the col/row_start */
if (var_cols_found == mdb->pg_buf[row_end-bitmask_sz-jumps_used-1] &&
jumps_used < num_of_jumps) {
row_start += 256;
col_start -= 256;
jumps_used++;
/* if the position of this var_col matches the number
* in the current jump table entry, then increment
* the jump_used and adjust the col/row_start */
if (var_cols_found == mdb->pg_buf[row_end-bitmask_sz-jumps_used-1] &&
jumps_used < num_of_jumps) {
row_start += 256;
col_start -= 256;
jumps_used++;
}
/* if we have the last var_col, use the eod offset to
* figure out where the end is */
if (var_cols_found==row_var_cols) {
len=eod - col_start;
//printf("len = %d eod %d col_start %d\n",len, eod, col_start);
} else {
var_entry_pos =
row_end -
bitmask_sz -
var_cols_found - 1;
len=mdb->pg_buf[var_entry_pos] - col_start;
} /* if found==var_cols */
while (len<0) len+=256;
fields[i].start = row_start + col_start;
fields[i].value = &mdb->pg_buf[row_start +col_start];
fields[i].siz = len;
col_start += len;
} else {
fields[i].start = 0;
fields[i].value = NULL;
fields[i].siz = 0;
fields[i].is_null = 1;
}
/* if we have the last var_col, use the eod offset to
* figure out where the end is */
if (var_cols_found==var_cols) {
len=eod - col_start;
//printf("len = %d eod %d col_start %d\n",len, eod, col_start);
} else {
var_entry_pos =
row_end -
bitmask_sz -
var_cols_found - 1;
len=mdb->pg_buf[var_entry_pos] - mdb->pg_buf[var_entry_pos+1];
} /* if found==var_cols */
while (len<0) len+=256;
fields[i].start = row_start + col_start;
fields[i].value = &mdb->pg_buf[row_start +col_start];
fields[i].siz = len;
col_start += len;
} /* if !fixed */
} /* for */
return num_cols;
}
/**
* mdb_crack_row:
* @mdb: Database handle
* @row_start: offset to start of row on current page
* @row_end: offset to end of row on current page
* @fields: pointer to MdbField array to be popluated by mdb_crack_row
*
* Cracks a row buffer apart into its component fields.
*
* A row buffer is that portion of a data page which contains the values for
* that row. Its beginning and end can be found in the row offset table.
*
* The resulting MdbField array contains pointers into the row for each field
* present. Be aware that by modifying field[]->value, you would be modifying
* the row buffer itself, not a copy.
*
* This routine is mostly used internally by mdb_fetch_row() but may have some
* applicability for advanced application programs.
*
* Return value: number of fields present.
*/
int
mdb_crack_row(MdbTableDef *table, int row_start, int row_end, MdbField *fields)
{