- char i_item[128], *i_item_ptr;
- int i_more, i_mode, i;
-
- ISAMC_PP pp;
- char f_item[128], *f_item_ptr;
- int f_more;
- int block_ptr[100]; /* block pointer (0 if none) */
- int dirty_ptr[100]; /* dirty flag pointer (1 if dirty) */
-
- int firstpos = 0;
- int nextpos = 0;
- int cat = 0;
- char r_item_buf[128]; /* temporary result output */
- char *r_buf; /* block with resulting data */
- int r_offset = 0; /* current offset in r_buf */
- int r_ptr[100]; /* offset pointer */
- int r_ptri = 0; /* pointer */
- void *r_clientData; /* encode client data */
-
- if (ipos == 0)
- return isc_merge_first (is, data);
-
- r_clientData = (*is->method->code_start)(ISAMC_ENCODE);
- r_buf = is->r_buf + ISAMC_BLOCK_OFFSET;
-
- pp = isc_pp_open (is, ipos);
- f_item_ptr = f_item;
- f_more = isc_read_item (pp, &f_item_ptr);
- cat = pp->cat;
-
- /* read first item from i */
- i_item_ptr = i_item;
- i_more = (*data->read_item)(data->clientData, &i_item_ptr, &i_mode);
- block_ptr[r_ptri] = pp->pos;
- dirty_ptr[r_ptri] = 0;
- r_ptr[r_ptri++] = 0;
-
- while (i_more || f_more)
- {
- char *r_item = r_item_buf;
- int cmp;
-
- if (!f_more)
- cmp = -1;
- else if (!i_more)
- cmp = 1;
- else
- cmp = (*is->method->compare_item)(i_item, f_item);
- if (cmp == 0) /* insert i=f */
- {
- if (!i_mode)
- {
- r_item = NULL;
- dirty_ptr[r_ptri-1] = 1;
- }
- else
- memcpy (r_item, f_item, f_item_ptr - f_item);
-
- /* move i */
- i_item_ptr = i_item;
- i_more = (*data->read_item)(data->clientData, &i_item_ptr,
- &i_mode);
- /* move f */
- f_item_ptr = f_item;
- f_more = isc_read_item (pp, &f_item_ptr);
- }
- else if (cmp > 0) /* insert f */
- {
- memcpy (r_item, f_item, f_item_ptr - f_item);
- /* move f */
- f_item_ptr = f_item;
- f_more = isc_read_item (pp, &f_item_ptr);
- }
- else /* insert i */
- {
- if (!i_mode) /* delete item which isn't there? */
- {
- logf (LOG_FATAL, "Inconsistent register");
- abort ();
- }
- memcpy (r_item, i_item, i_item_ptr - i_item);
- dirty_ptr[r_ptri-1] = 1;
- /* move i */
- i_item_ptr = i_item;
- i_more = (*data->read_item)(data->clientData, &i_item_ptr,
- &i_mode);
- }
- if (r_item) /* insert resulting item? */
- {
- char *r_out_ptr = r_buf + r_offset;
- int new_offset;
- int border;
-
- /* border set to initial fill or block size depending on
- whether we are creating a new one or updating and old
- */
- if (block_ptr[r_ptri-1])
- border = r_ptr[r_ptri-1] + is->method->filecat[cat].bsize
- -ISAMC_BLOCK_OFFSET;
- else
- border = r_ptr[r_ptri-1] + is->method->filecat[cat].ifill
- -ISAMC_BLOCK_OFFSET;
-
- (*is->method->code_item)(ISAMC_ENCODE, r_clientData,
- &r_out_ptr, &r_item);
- new_offset = r_out_ptr - r_buf;
-
- if (border >= r_offset && border < new_offset)
- {
- /* Initial fill of current block category reached...
- Save offset in r_ptr
- */
- r_ptr[r_ptri++] = r_offset;
- if (cat == is->max_cat)
- {
- /* We are dealing with block of max size. Block(s)
- will be flushed. Note: the block(s) are surely not
- the last one(s).
- */
- if (is->method->debug > 1)
- logf (LOG_LOG, "isc: flush %d sections", r_ptri-1);
- isc_flush_blocks (is, r_ptr, r_ptri, r_buf,
- &nextpos, &firstpos, cat, 0);
- r_ptri = 0;
- r_ptr[r_ptri++] = 0;
- memcpy (r_buf, r_buf + r_offset, new_offset - r_offset);
- new_offset = (new_offset - r_offset);
- }
- }
- r_offset = new_offset;
- if (cat < is->max_cat &&
- r_ptri>is->method->filecat[cat].mblocks)
- {
- /* Max number blocks in current category reached ->
- must switch to next category (with larger block size)
- */
- int j = 1;
- cat++;
- /* r_ptr[0] = r_ptr[0] = 0 true anyway.. */
- /* AD: Any old blocks should be deleted */
- for (i = 2; i < r_ptri; i++)
- {
- border = is->method->filecat[cat].ifill -
- ISAMC_BLOCK_OFFSET + r_ptr[j-1];
- if (r_ptr[i] > border && r_ptr[i-1] <= border)
- r_ptr[j++] = r_ptr[i-1];
- }
- r_ptri = j;
- }
- }
- }
- r_ptr[r_ptri++] = r_offset;
- /* flush rest of block(s) in r_buf */
- if (is->method->debug > 1)
- logf (LOG_LOG, "isc: flush rest, %d sections", r_ptri-1);
- isc_flush_blocks (is, r_ptr, r_ptri, r_buf, &nextpos, &firstpos, cat, 1);
- (*is->method->code_stop)(ISAMC_ENCODE, r_clientData);
- return cat + firstpos * 8;