Function write_master_page1

internal/cbm/sqlite_writer.c:1918–1975

Build master records, write page 1 B-tree + file header. */

/* Build master records, write page 1 B-tree + file header. */
static int write_master_page1(FILE *fp, MasterEntry *master, int master_count, uint32_t next_page) {
    const uint8_t **master_records = (const uint8_t **)malloc(master_count * sizeof(uint8_t *));
    int *master_lens = (int *)malloc(master_count * sizeof(int));
    int64_t *master_rowids = (int64_t *)malloc(master_count * sizeof(int64_t));
    for (int i = 0; i < master_count; i++) {
        master_rowids[i] = i + SKIP_ONE;
        master_records[i] = build_master_record(&master[i], &master_lens[i]);
    }

    uint8_t page1[CBM_PAGE_SIZE];
    memset(page1, 0, CBM_PAGE_SIZE);
    int hdr = SQLITE_HEADER_SIZE;
    page1[hdr] = BTREE_LEAF_TABLE;
    int content_off = CBM_PAGE_SIZE;
    int ptr_off = hdr + BTREE_HEADER_SIZE;
    int mcell_count = 0;

    for (int i = 0; i < master_count; i++) {
        int cell_len = 0;
        uint8_t *cell =
            build_table_cell(master_rowids[i], master_records[i], master_lens[i], &cell_len);
        int available = content_off - ptr_off - CELL_PTR_SIZE;
        if (!cell || cell_len > available) {
            free(cell);
            for (int j = 0; j < master_count; j++) {
                free((void *)master_records[j]);
            }
            free(master_records);
            free(master_lens);
            free(master_rowids);
            return ERR_MASTER_OVERFLOW;
        }
        content_off -= cell_len;
        memcpy(page1 + content_off, cell, cell_len);
        put_u16(page1 + ptr_off, (uint16_t)content_off);
        ptr_off += CELL_PTR_SIZE;
        mcell_count++;
        free(cell);
    }

    put_u16(page1 + hdr + HDR_FREEBLOCK_OFF, 0);
    put_u16(page1 + hdr + HDR_CELLCOUNT_OFF, (uint16_t)mcell_count);
    put_u16(page1 + hdr + HDR_CONTENT_OFF, (uint16_t)content_off);
    page1[hdr + HDR_FRAGBYTES_OFF] = 0;

    write_sqlite_file_header(page1, next_page - SKIP_ONE);

    (void)fseek(fp, 0, SEEK_SET);
    (void)fwrite(page1, SKIP_ONE, CBM_PAGE_SIZE, fp);

    for (int i = 0; i < master_count; i++) {
        free((void *)master_records[i]);
    }
    free(master_records);
    free(master_lens);
    free(master_rowids);
    return 0;
}