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lightning-sunbird  0.9+nobinonly
Defines | Functions
h_page.c File Reference
#include "watcomfx.h"
#include <sys/types.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include "mcom_db.h"
#include "hash.h"
#include "page.h"

Go to the source code of this file.

Defines

#define MY_LSEEK   new_lseek
#define PAGE_INIT(P)
#define MAX_UGLY_SPLIT_LOOPS   10000
#define BYTE_MASK   ((1 << INT_BYTE_SHIFT) -1)
#define OVMSG   "HASH: Out of overflow pages. Increase page size\n"

Functions

long new_lseek (int fd, long pos, int start)
int mkstempflags (char *path, int extraFlags)
static uint32 *fetch_bitmap __P ((HTAB *, uint32))
static uint32 first_free __P ((uint32))
static int open_temp __P ((HTAB *))
static void squeeze_key __P ((uint16 *, const DBT *, const DBT *))
static int ugly_split __P ((HTAB *, uint32, BUFHEAD *, BUFHEAD *, int, int))
static void putpair (char *p, const DBT *key, DBT *val)
int __delpair (HTAB *hashp, BUFHEAD *bufp, int ndx)
int __split_page (HTAB *hashp, uint32 obucket, uint32 nbucket)
static int ugly_split (HTAB *hashp, uint32 obucket, BUFHEAD *old_bufp, BUFHEAD *new_bufp, int copyto, int moved)
int __addel (HTAB *hashp, BUFHEAD *bufp, const DBT *key, const DBT *val)
BUFHEAD * __add_ovflpage (HTAB *hashp, BUFHEAD *bufp)
int __get_page (HTAB *hashp, char *p, uint32 bucket, int is_bucket, int is_disk, int is_bitmap)
int __put_page (HTAB *hashp, char *p, uint32 bucket, int is_bucket, int is_bitmap)
int __ibitmap (HTAB *hashp, int pnum, int nbits, int ndx)
static uint32 first_free (uint32 map)
static uint16 overflow_page (HTAB *hashp)
void __free_ovflpage (HTAB *hashp, BUFHEAD *obufp)
static int open_temp (HTAB *hashp)
static void squeeze_key (uint16 *sp, const DBT *key, const DBT *val)
static uint32fetch_bitmap (HTAB *hashp, uint32 ndx)

Define Documentation

#define BYTE_MASK   ((1 << INT_BYTE_SHIFT) -1)

Definition at line 912 of file h_page.c.

Definition at line 406 of file h_page.c.

Definition at line 38 of file h_page.c.

#define OVMSG   "HASH: Out of overflow pages. Increase page size\n"
#define PAGE_INIT (   P)
Value:
{ \
       ((uint16 *)(P))[0] = 0; \
       ((uint16 *)(P))[1] = hashp->BSIZE - 3 * sizeof(uint16); \
       ((uint16 *)(P))[2] = hashp->BSIZE; \
}

Definition at line 102 of file h_page.c.


Function Documentation

BUFHEAD* __add_ovflpage ( HTAB hashp,
BUFHEAD *  bufp 
)

Definition at line 635 of file h_page.c.

{
       register uint16 *sp;
       uint16 ndx, ovfl_num;
#ifdef DEBUG1
       int tmp1, tmp2;
#endif
       sp = (uint16 *)bufp->page;

       /* Check if we are dynamically determining the fill factor */
       if (hashp->FFACTOR == DEF_FFACTOR) {
              hashp->FFACTOR = sp[0] >> 1;
              if (hashp->FFACTOR < MIN_FFACTOR)
                     hashp->FFACTOR = MIN_FFACTOR;
       }
       bufp->flags |= BUF_MOD;
       ovfl_num = overflow_page(hashp);
#ifdef DEBUG1
       tmp1 = bufp->addr;
       tmp2 = bufp->ovfl ? bufp->ovfl->addr : 0;
#endif
       if (!ovfl_num || !(bufp->ovfl = __get_buf(hashp, ovfl_num, bufp, 1)))
              return (NULL);
       bufp->ovfl->flags |= BUF_MOD;
#ifdef DEBUG1
       (void)fprintf(stderr, "ADDOVFLPAGE: %d->ovfl was %d is now %d\n",
           tmp1, tmp2, bufp->ovfl->addr);
#endif
       ndx = sp[0];
       /*
        * Since a pair is allocated on a page only if there's room to add
        * an overflow page, we know that the OVFL information will fit on
        * the page.
        */
       sp[ndx + 4] = OFFSET(sp);
       sp[ndx + 3] = FREESPACE(sp) - OVFLSIZE;
       sp[ndx + 1] = ovfl_num;
       sp[ndx + 2] = OVFLPAGE;
       sp[0] = ndx + 2;
#ifdef HASH_STATISTICS
       hash_overflows++;
#endif
       return (bufp->ovfl);
}

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int __addel ( HTAB hashp,
BUFHEAD *  bufp,
const DBT key,
const DBT val 
)

Definition at line 542 of file h_page.c.

{
       register uint16 *bp, *sop;
       int do_expand;

       bp = (uint16 *)bufp->page;
       do_expand = 0;
       while (bp[0] && (bp[2] < REAL_KEY || bp[bp[0]] < REAL_KEY))
              /* Exception case */
              if (bp[2] == FULL_KEY_DATA && bp[0] == 2)
                     /* This is the last page of a big key/data pair
                        and we need to add another page */
                     break;
              else if (bp[2] < REAL_KEY && bp[bp[0]] != OVFLPAGE) {
                     bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0);
                     if (!bufp)
                       {
#ifdef DEBUG
                            assert(0);
#endif
                            return (-1);
                       }
                     bp = (uint16 *)bufp->page;
              } else
                     /* Try to squeeze key on this page */
                     if (FREESPACE(bp) > PAIRSIZE(key, val)) {
                       {
                            squeeze_key(bp, key, val);

                            /* LJM: I added this because I think it was
                             * left out on accident.
                             * if this isn't incremented nkeys will not
                             * be the actual number of keys in the db.
                             */
                            hashp->NKEYS++;
                            return (0);
                       }
                     } else {
                            bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0);
                            if (!bufp)
                           {
#ifdef DEBUG
                                assert(0);
#endif
                                   return (-1);
                              }
                            bp = (uint16 *)bufp->page;
                     }

       if (PAIRFITS(bp, key, val))
              putpair(bufp->page, key, (DBT *)val);
       else {
              do_expand = 1;
              bufp = __add_ovflpage(hashp, bufp);
              if (!bufp)
             {
#ifdef DEBUG
                  assert(0);
#endif
                     return (-1);
                }
              sop = (uint16 *)bufp->page;

              if (PAIRFITS(sop, key, val))
                     putpair((char *)sop, key, (DBT *)val);
              else
                     if (__big_insert(hashp, bufp, key, val))
                 {
#ifdef DEBUG
                      assert(0);
#endif
                         return (-1);
                    }
       }
       bufp->flags |= BUF_MOD;
       /*
        * If the average number of keys per bucket exceeds the fill factor,
        * expand the table.
        */
       hashp->NKEYS++;
       if (do_expand ||
           (hashp->NKEYS / (hashp->MAX_BUCKET + 1) > hashp->FFACTOR))
              return (__expand_table(hashp));
       return (0);
}

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int __delpair ( HTAB hashp,
BUFHEAD *  bufp,
int  ndx 
)

Definition at line 211 of file h_page.c.

{
       register uint16 *bp, newoff;
       register int n;
       uint16 pairlen;

       bp = (uint16 *)bufp->page;
       n = bp[0];

       if (bp[ndx + 1] < REAL_KEY)
              return (__big_delete(hashp, bufp));
       if (ndx != 1)
              newoff = bp[ndx - 1];
       else
              newoff = hashp->BSIZE;
       pairlen = newoff - bp[ndx + 1];

       if (ndx != (n - 1)) {
              /* Hard Case -- need to shuffle keys */
              register int i;
              register char *src = bufp->page + (int)OFFSET(bp);
              uint32 dst_offset = (uint32)OFFSET(bp) + (uint32)pairlen;
              register char *dst = bufp->page + dst_offset;
              uint32 length = bp[ndx + 1] - OFFSET(bp);

              /*
               * +-----------+XXX+---------+XXX+---------+---------> +infinity
               * |           |             |             |
               * 0           src_offset    dst_offset    BSIZE
               *
               * Dst_offset is > src_offset, so if src_offset were bad, dst_offset
               * would be too, therefore we check only dst_offset.
               *
               * If dst_offset is >= BSIZE, either OFFSET(bp), or pairlen, or both
               * is corrupted.
               *
               * Once we know dst_offset is < BSIZE, we can subtract it from BSIZE
               * to get an upper bound on length.
               */
              if(dst_offset > (uint32)hashp->BSIZE)
                     return(DATABASE_CORRUPTED_ERROR);

              if(length > (uint32)(hashp->BSIZE - dst_offset))
                     return(DATABASE_CORRUPTED_ERROR);

              memmove(dst, src, length);

              /* Now adjust the pointers */
              for (i = ndx + 2; i <= n; i += 2) {
                     if (bp[i + 1] == OVFLPAGE) {
                            bp[i - 2] = bp[i];
                            bp[i - 1] = bp[i + 1];
                     } else {
                            bp[i - 2] = bp[i] + pairlen;
                            bp[i - 1] = bp[i + 1] + pairlen;
                     }
              }
       }
       /* Finally adjust the page data */
       bp[n] = OFFSET(bp) + pairlen;
       bp[n - 1] = bp[n + 1] + pairlen + 2 * sizeof(uint16);
       bp[0] = n - 2;
       hashp->NKEYS--;

       bufp->flags |= BUF_MOD;
       return (0);
}

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void __free_ovflpage ( HTAB hashp,
BUFHEAD *  obufp 
)

Definition at line 1107 of file h_page.c.

{
       uint16 addr;
       uint32 *freep;
       uint32 bit_address, free_page, free_bit;
       uint16 ndx;

       if(!obufp || !obufp->addr)
           return;

       addr = obufp->addr;
#ifdef DEBUG1
       (void)fprintf(stderr, "Freeing %d\n", addr);
#endif
       ndx = (((uint16)addr) >> SPLITSHIFT);
       bit_address =
           (ndx ? hashp->SPARES[ndx - 1] : 0) + (addr & SPLITMASK) - 1;
       if (bit_address < (uint32)hashp->LAST_FREED)
              hashp->LAST_FREED = bit_address;
       free_page = (bit_address >> (hashp->BSHIFT + BYTE_SHIFT));
       free_bit = bit_address & ((hashp->BSIZE << BYTE_SHIFT) - 1);

       if (!(freep = hashp->mapp[free_page])) 
              freep = fetch_bitmap(hashp, free_page);

#ifdef DEBUG
       /*
        * This had better never happen.  It means we tried to read a bitmap
        * that has already had overflow pages allocated off it, and we
        * failed to read it from the file.
        */
       if (!freep)
         {
              assert(0);
              return;
         }
#endif
       CLRBIT(freep, free_bit);
#ifdef DEBUG2
       (void)fprintf(stderr, "FREE_OVFLPAGE: ADDR: %d BIT: %d PAGE %d\n",
           obufp->addr, free_bit, free_page);
#endif
       __reclaim_buf(hashp, obufp);
}

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int __get_page ( HTAB hashp,
char *  p,
uint32  bucket,
int  is_bucket,
int  is_disk,
int  is_bitmap 
)

Definition at line 686 of file h_page.c.

{
       register int fd, page;
       size_t size;
       int rsize;
       uint16 *bp;

       fd = hashp->fp;
       size = hashp->BSIZE;

       if ((fd == -1) || !is_disk) {
              PAGE_INIT(p);
              return (0);
       }
       if (is_bucket)
              page = BUCKET_TO_PAGE(bucket);
       else
              page = OADDR_TO_PAGE(bucket);
       if ((MY_LSEEK(fd, (off_t)page << hashp->BSHIFT, SEEK_SET) == -1) ||
           ((rsize = read(fd, p, size)) == -1))
              return (-1);

       bp = (uint16 *)p;
       if (!rsize)
              bp[0] = 0;    /* We hit the EOF, so initialize a new page */
       else
              if ((unsigned)rsize != size) {
                     errno = EFTYPE;
                     return (-1);
              }

       if (!is_bitmap && !bp[0]) {
              PAGE_INIT(p);
       } else {

#ifdef DEBUG
              if(BYTE_ORDER == LITTLE_ENDIAN)
                {
                     int is_little_endian;
                     is_little_endian = BYTE_ORDER;
                }
              else if(BYTE_ORDER == BIG_ENDIAN)
                {
                     int is_big_endian;
                     is_big_endian = BYTE_ORDER;
                }
              else
                {
                     assert(0);
                }
#endif

              if (hashp->LORDER != BYTE_ORDER) {
                     register int i, max;

                     if (is_bitmap) {
                            max = hashp->BSIZE >> 2; /* divide by 4 */
                            for (i = 0; i < max; i++)
                                   M_32_SWAP(((int *)p)[i]);
                     } else {
                            M_16_SWAP(bp[0]);
                            max = bp[0] + 2;

                     /* bound the size of max by
                      * the maximum number of entries
                      * in the array
                      */
                            if((unsigned)max > (size / sizeof(uint16)))
                                   return(DATABASE_CORRUPTED_ERROR);

                            /* do the byte order swap
                             */
                            for (i = 1; i <= max; i++)
                                   M_16_SWAP(bp[i]);
                     }
              }

              /* check the validity of the page here
               * (after doing byte order swaping if necessary)
               */
              if(!is_bitmap && bp[0] != 0)
                {
                     uint16 num_keys = bp[0];
                     uint16 offset;
                     uint16 i;

                     /* bp[0] is supposed to be the number of
                      * entries currently in the page.  If
                      * bp[0] is too large (larger than the whole
                      * page) then the page is corrupted
                      */
                     if(bp[0] > (size / sizeof(uint16)))
                            return(DATABASE_CORRUPTED_ERROR);
                     
                     /* bound free space */
                     if(FREESPACE(bp) > size)
                            return(DATABASE_CORRUPTED_ERROR);
              
                     /* check each key and data offset to make
                      * sure they are all within bounds they
                      * should all be less than the previous
                      * offset as well.
                      */
                     offset = size;
                     for(i=1 ; i <= num_keys; i+=2)
                       {
                            /* ignore overflow pages etc. */
                            if(bp[i+1] >= REAL_KEY)
                              {
                                          
                                   if(bp[i] > offset || bp[i+1] > bp[i])                   
                                          return(DATABASE_CORRUPTED_ERROR);
                     
                                   offset = bp[i+1];
                              }
                            else
                              {
                                   /* there are no other valid keys after
                                    * seeing a non REAL_KEY
                                    */
                                   break;
                              }
                       }
              }
       }
       return (0);
}

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int __ibitmap ( HTAB hashp,
int  pnum,
int  nbits,
int  ndx 
)

Definition at line 918 of file h_page.c.

{
       uint32 *ip;
       size_t clearbytes, clearints;

       if ((ip = (uint32 *)malloc((size_t)hashp->BSIZE)) == NULL)
              return (1);
       hashp->nmaps++;
       clearints = ((nbits - 1) >> INT_BYTE_SHIFT) + 1;
       clearbytes = clearints << INT_TO_BYTE;
       (void)memset((char *)ip, 0, clearbytes);
       (void)memset(((char *)ip) + clearbytes, 0xFF,
           hashp->BSIZE - clearbytes);
       ip[clearints - 1] = ALL_SET << (nbits & BYTE_MASK);
       SETBIT(ip, 0);
       hashp->BITMAPS[ndx] = (uint16)pnum;
       hashp->mapp[ndx] = ip;
       return (0);
}

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static uint32* fetch_bitmap __P ( (HTAB *, uint32 ) [static]
static uint32 first_free __P ( (uint32 ) [static]
static uint16 overflow_page __P ( (HTAB *)  ) [static]
static void squeeze_key __P ( (uint16 *, const DBT *, const DBT *)  ) [static]
static int ugly_split __P ( (HTAB *, uint32, BUFHEAD *, BUFHEAD *, int, int ) [static]
int __put_page ( HTAB hashp,
char *  p,
uint32  bucket,
int  is_bucket,
int  is_bitmap 
)

Definition at line 827 of file h_page.c.

{
       register int fd, page;
       size_t size;
       int wsize;
       off_t offset;

       size = hashp->BSIZE;
       if ((hashp->fp == -1) && open_temp(hashp))
              return (-1);
       fd = hashp->fp;

       if (hashp->LORDER != BYTE_ORDER) {
              register int i;
              register int max;

              if (is_bitmap) {
                     max = hashp->BSIZE >> 2;    /* divide by 4 */
                     for (i = 0; i < max; i++)
                            M_32_SWAP(((int *)p)[i]);
              } else {
                     max = ((uint16 *)p)[0] + 2;

            /* bound the size of max by
             * the maximum number of entries
             * in the array
             */
            if((unsigned)max > (size / sizeof(uint16)))
                return(DATABASE_CORRUPTED_ERROR);

                     for (i = 0; i <= max; i++)
                            M_16_SWAP(((uint16 *)p)[i]);

              }
       }

       if (is_bucket)
              page = BUCKET_TO_PAGE(bucket);
       else
              page = OADDR_TO_PAGE(bucket);
       offset = (off_t)page << hashp->BSHIFT;
       if ((MY_LSEEK(fd, offset, SEEK_SET) == -1) ||
           ((wsize = write(fd, p, size)) == -1))
              /* Errno is set */
              return (-1);
       if ((unsigned)wsize != size) {
              errno = EFTYPE;
              return (-1);
       }
#if defined(_WIN32) || defined(_WINDOWS) 
       if (offset + size > hashp->file_size) {
              hashp->updateEOF = 1;
       }
#endif
       /* put the page back the way it was so that it isn't byteswapped
        * if it remains in memory - LJM
        */
       if (hashp->LORDER != BYTE_ORDER) {
              register int i;
              register int max;

              if (is_bitmap) {
                     max = hashp->BSIZE >> 2;    /* divide by 4 */
                     for (i = 0; i < max; i++)
                            M_32_SWAP(((int *)p)[i]);
              } else {
              uint16 *bp = (uint16 *)p;

                     M_16_SWAP(bp[0]);
                     max = bp[0] + 2;

                     /* no need to bound the size if max again
                      * since it was done already above
                      */

                     /* do the byte order re-swap
                      */
                     for (i = 1; i <= max; i++)
                            M_16_SWAP(bp[i]);
              }
       }

       return (0);
}

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int __split_page ( HTAB hashp,
uint32  obucket,
uint32  nbucket 
)

Definition at line 284 of file h_page.c.

{
       register BUFHEAD *new_bufp, *old_bufp;
       register uint16 *ino;
       register uint16 *tmp_uint16_array;
       register char *np;
       DBT key, val;
    uint16 n, ndx;
       int retval;
       uint16 copyto, diff, moved;
       size_t off;
       char *op;

       copyto = (uint16)hashp->BSIZE;
       off = (uint16)hashp->BSIZE;
       old_bufp = __get_buf(hashp, obucket, NULL, 0);
       if (old_bufp == NULL)
              return (-1);
       new_bufp = __get_buf(hashp, nbucket, NULL, 0);
       if (new_bufp == NULL)
              return (-1);

       old_bufp->flags |= (BUF_MOD | BUF_PIN);
       new_bufp->flags |= (BUF_MOD | BUF_PIN);

       ino = (uint16 *)(op = old_bufp->page);
       np = new_bufp->page;

       moved = 0;

       for (n = 1, ndx = 1; n < ino[0]; n += 2) {
              if (ino[n + 1] < REAL_KEY) {
                     retval = ugly_split(hashp, obucket, old_bufp, new_bufp,
                         (int)copyto, (int)moved);
                     old_bufp->flags &= ~BUF_PIN;
                     new_bufp->flags &= ~BUF_PIN;
                     return (retval);

              }
              key.data = (uint8 *)op + ino[n];

              /* check here for ino[n] being greater than
               * off.  If it is then the database has
               * been corrupted.
               */
              if(ino[n] > off)
                     return(DATABASE_CORRUPTED_ERROR);

              key.size = off - ino[n];

#ifdef DEBUG
              /* make sure the size is positive */
              assert(((int)key.size) > -1);
#endif

              if (__call_hash(hashp, (char *)key.data, key.size) == obucket) {
                     /* Don't switch page */
                     diff = copyto - off;
                     if (diff) {
                            copyto = ino[n + 1] + diff;
                            memmove(op + copyto, op + ino[n + 1],
                                off - ino[n + 1]);
                            ino[ndx] = copyto + ino[n] - ino[n + 1];
                            ino[ndx + 1] = copyto;
                     } else
                            copyto = ino[n + 1];
                     ndx += 2;
              } else {
                     /* Switch page */
                     val.data = (uint8 *)op + ino[n + 1];
                     val.size = ino[n] - ino[n + 1];

                     /* if the pair doesn't fit something is horribly
                      * wrong.  LJM
                      */
                     tmp_uint16_array = (uint16*)np;
                     if(!PAIRFITS(tmp_uint16_array, &key, &val))
                            return(DATABASE_CORRUPTED_ERROR);

                     putpair(np, &key, &val);
                     moved += 2;
              }

              off = ino[n + 1];
       }

       /* Now clean up the page */
       ino[0] -= moved;
       FREESPACE(ino) = copyto - sizeof(uint16) * (ino[0] + 3);
       OFFSET(ino) = copyto;

#ifdef DEBUG3
       (void)fprintf(stderr, "split %d/%d\n",
           ((uint16 *)np)[0] / 2,
           ((uint16 *)op)[0] / 2);
#endif
       /* unpin both pages */
       old_bufp->flags &= ~BUF_PIN;
       new_bufp->flags &= ~BUF_PIN;
       return (0);
}

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static uint32* fetch_bitmap ( HTAB hashp,
uint32  ndx 
) [static]

Definition at line 1254 of file h_page.c.

{
       if (ndx >= (unsigned)hashp->nmaps)
              return (NULL);
       if ((hashp->mapp[ndx] = (uint32 *)malloc((size_t)hashp->BSIZE)) == NULL)
              return (NULL);
       if (__get_page(hashp,
           (char *)hashp->mapp[ndx], hashp->BITMAPS[ndx], 0, 1, 1)) {
              free(hashp->mapp[ndx]);
              hashp->mapp[ndx] = NULL; /* NEW: 9-11-95 */
              return (NULL);
       }                 
       return (hashp->mapp[ndx]);
}

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static uint32 first_free ( uint32  map) [static]

Definition at line 939 of file h_page.c.

{
       register uint32 i, mask;

       mask = 0x1;
       for (i = 0; i < BITS_PER_MAP; i++) {
              if (!(mask & map))
                     return (i);
              mask = mask << 1;
       }
       return (i);
}

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int mkstempflags ( char *  path,
int  extraFlags 
)

Definition at line 80 of file mktemp.c.

{
       int fd;

       return (_gettemp(path, &fd, extraFlags) ? fd : -1);
}

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long new_lseek ( int  fd,
long  pos,
int  start 
)

Definition at line 112 of file h_page.c.

{
       long cur_pos=0;
       long end_pos=0;
       long seek_pos=0;

       if(origin == SEEK_CUR)
      {       
       if(offset < 1)                                                   
              return(lseek(fd, offset, SEEK_CUR));

              cur_pos = lseek(fd, 0, SEEK_CUR);

              if(cur_pos < 0)
                     return(cur_pos);
         }
                                                                       
       end_pos = lseek(fd, 0, SEEK_END);
       if(end_pos < 0)
              return(end_pos);

       if(origin == SEEK_SET)
              seek_pos = offset;
       else if(origin == SEEK_CUR)
              seek_pos = cur_pos + offset;
       else if(origin == SEEK_END)
              seek_pos = end_pos + offset;
       else
         {
              assert(0);
              return(-1);
         }

       /* the seek position desired is before the
        * end of the file.  We don't need
        * to do anything special except the seek.
        */
       if(seek_pos <= end_pos)
              return(lseek(fd, seek_pos, SEEK_SET));
              
         /* the seek position is beyond the end of the
          * file.  Write zero's to the end.
          *
          * we are already at the end of the file so
          * we just need to "write()" zeros for the
          * difference between seek_pos-end_pos and
          * then seek to the position to finish
          * the call
          */
         { 
              char buffer[1024];
              long len = seek_pos-end_pos;
              memset(&buffer, 0, 1024);
              while(len > 0)
             {
               write(fd, (char*)&buffer, (size_t)(1024 > len ? len : 1024));
                  len -= 1024;
                }
              return(lseek(fd, seek_pos, SEEK_SET));
         }           

}

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static int open_temp ( HTAB hashp) [static]

Definition at line 1158 of file h_page.c.

{
#ifdef XP_OS2
       hashp->fp = mkstemp(NULL);
#else
#if !defined(_WIN32) && !defined(_WINDOWS) && !defined(macintosh)
       sigset_t set, oset;
#endif
#if !defined(macintosh)
       char * tmpdir;
       size_t len;
       char last;
#endif
       static const char namestr[] = "/_hashXXXXXX";
       char filename[1024];

#if !defined(_WIN32) && !defined(_WINDOWS) && !defined(macintosh)
       /* Block signals; make sure file goes away at process exit. */
       (void)sigfillset(&set);
       (void)sigprocmask(SIG_BLOCK, &set, &oset);
#endif

       filename[0] = 0;
#if defined(macintosh)
       strcat(filename, namestr + 1);
#else
       tmpdir = getenv("TMP");
       if (!tmpdir)
              tmpdir = getenv("TMPDIR");
       if (!tmpdir)
              tmpdir = getenv("TEMP");
       if (!tmpdir)
              tmpdir = ".";
       len = strlen(tmpdir);
       if (len && len < (sizeof filename - sizeof namestr)) {
              strcpy(filename, tmpdir);
       }
       len = strlen(filename);
       last = tmpdir[len - 1];
       strcat(filename, (last == '/' || last == '\\') ? namestr + 1 : namestr);
#endif

#if defined(_WIN32) || defined(_WINDOWS)
       if ((hashp->fp = mkstempflags(filename, _O_BINARY|_O_TEMPORARY)) != -1) {
              if (hashp->filename) {
                     free(hashp->filename);
              }
              hashp->filename = strdup(filename);
              hashp->is_temp = 1;
       }
#else
       if ((hashp->fp = mkstemp(filename)) != -1) {
              (void)unlink(filename);
#if !defined(macintosh)
              (void)fcntl(hashp->fp, F_SETFD, 1);
#endif                                                           
       }
#endif

#if !defined(_WIN32) && !defined(_WINDOWS) && !defined(macintosh)
       (void)sigprocmask(SIG_SETMASK, &oset, (sigset_t *)NULL);
#endif
#endif  /* !OS2 */
       return (hashp->fp != -1 ? 0 : -1);
}

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static uint16 overflow_page ( HTAB hashp) [static]

Definition at line 953 of file h_page.c.

{
       register uint32 *freep=NULL;
       register int max_free, offset, splitnum;
       uint16 addr;
       uint32 i;
       int bit, first_page, free_bit, free_page, in_use_bits, j;
#ifdef DEBUG2
       int tmp1, tmp2;
#endif
       splitnum = hashp->OVFL_POINT;
       max_free = hashp->SPARES[splitnum];

       free_page = (max_free - 1) >> (hashp->BSHIFT + BYTE_SHIFT);
       free_bit = (max_free - 1) & ((hashp->BSIZE << BYTE_SHIFT) - 1);

       /* Look through all the free maps to find the first free block */
       first_page = hashp->LAST_FREED >>(hashp->BSHIFT + BYTE_SHIFT);
       for ( i = first_page; i <= (unsigned)free_page; i++ ) {
              if (!(freep = (uint32 *)hashp->mapp[i]) &&
                  !(freep = fetch_bitmap(hashp, i)))
                     return (0);
              if (i == (unsigned)free_page)
                     in_use_bits = free_bit;
              else
                     in_use_bits = (hashp->BSIZE << BYTE_SHIFT) - 1;
              
              if (i == (unsigned)first_page) {
                     bit = hashp->LAST_FREED &
                         ((hashp->BSIZE << BYTE_SHIFT) - 1);
                     j = bit / BITS_PER_MAP;
                     bit = bit & ~(BITS_PER_MAP - 1);
              } else {
                     bit = 0;
                     j = 0;
              }
              for (; bit <= in_use_bits; j++, bit += BITS_PER_MAP)
                     if (freep[j] != ALL_SET)
                            goto found;
       }

       /* No Free Page Found */
       hashp->LAST_FREED = hashp->SPARES[splitnum];
       hashp->SPARES[splitnum]++;
       offset = hashp->SPARES[splitnum] -
           (splitnum ? hashp->SPARES[splitnum - 1] : 0);

#define       OVMSG  "HASH: Out of overflow pages.  Increase page size\n"
       if (offset > SPLITMASK) {
              if (++splitnum >= NCACHED) {
#ifndef macintosh
                     (void)write(STDERR_FILENO, OVMSG, sizeof(OVMSG) - 1);
#endif
                     return (0);
              }
              hashp->OVFL_POINT = splitnum;
              hashp->SPARES[splitnum] = hashp->SPARES[splitnum-1];
              hashp->SPARES[splitnum-1]--;
              offset = 1;
       }

       /* Check if we need to allocate a new bitmap page */
       if (free_bit == (hashp->BSIZE << BYTE_SHIFT) - 1) {
              free_page++;
              if (free_page >= NCACHED) {
#ifndef macintosh
                     (void)write(STDERR_FILENO, OVMSG, sizeof(OVMSG) - 1);
#endif
                     return (0);
              }
              /*
               * This is tricky.  The 1 indicates that you want the new page
               * allocated with 1 clear bit.  Actually, you are going to
               * allocate 2 pages from this map.  The first is going to be
               * the map page, the second is the overflow page we were
               * looking for.  The init_bitmap routine automatically, sets
               * the first bit of itself to indicate that the bitmap itself
               * is in use.  We would explicitly set the second bit, but
               * don't have to if we tell init_bitmap not to leave it clear
               * in the first place.
               */
              if (__ibitmap(hashp,
                  (int)OADDR_OF(splitnum, offset), 1, free_page))
                     return (0);
              hashp->SPARES[splitnum]++;
#ifdef DEBUG2
              free_bit = 2;
#endif
              offset++;
              if (offset > SPLITMASK) {
                     if (++splitnum >= NCACHED) {
#ifndef macintosh
                            (void)write(STDERR_FILENO, OVMSG,
                                sizeof(OVMSG) - 1);
#endif
                            return (0);
                     }
                     hashp->OVFL_POINT = splitnum;
                     hashp->SPARES[splitnum] = hashp->SPARES[splitnum-1];
                     hashp->SPARES[splitnum-1]--;
                     offset = 0;
              }
       } else {
              /*
               * Free_bit addresses the last used bit.  Bump it to address
               * the first available bit.
               */
              free_bit++;
              SETBIT(freep, free_bit);
       }

       /* Calculate address of the new overflow page */
       addr = OADDR_OF(splitnum, offset);
#ifdef DEBUG2
       (void)fprintf(stderr, "OVERFLOW_PAGE: ADDR: %d BIT: %d PAGE %d\n",
           addr, free_bit, free_page);
#endif
       return (addr);

found:
       bit = bit + first_free(freep[j]);
       SETBIT(freep, bit);
#ifdef DEBUG2
       tmp1 = bit;
       tmp2 = i;
#endif
       /*
        * Bits are addressed starting with 0, but overflow pages are addressed
        * beginning at 1. Bit is a bit addressnumber, so we need to increment
        * it to convert it to a page number.
        */
       bit = 1 + bit + (i * (hashp->BSIZE << BYTE_SHIFT));
       if (bit >= hashp->LAST_FREED)
              hashp->LAST_FREED = bit - 1;

       /* Calculate the split number for this page */
       for (i = 0; (i < (unsigned)splitnum) && (bit > hashp->SPARES[i]); i++) {}
       offset = (i ? bit - hashp->SPARES[i - 1] : bit);
       if (offset >= SPLITMASK)
              return (0);   /* Out of overflow pages */
       addr = OADDR_OF(i, offset);
#ifdef DEBUG2
       (void)fprintf(stderr, "OVERFLOW_PAGE: ADDR: %d BIT: %d PAGE %d\n",
           addr, tmp1, tmp2);
#endif

       /* Allocate and return the overflow page */
       return (addr);
}

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static void putpair ( char *  p,
const DBT key,
DBT val 
) [static]

Definition at line 181 of file h_page.c.

{
       register uint16 *bp, n, off;

       bp = (uint16 *)p;

       /* Enter the key first. */
       n = bp[0];

       off = OFFSET(bp) - key->size;
       memmove(p + off, key->data, key->size);
       bp[++n] = off;

       /* Now the data. */
       off -= val->size;
       memmove(p + off, val->data, val->size);
       bp[++n] = off;

       /* Adjust page info. */
       bp[0] = n;
       bp[n + 1] = off - ((n + 3) * sizeof(uint16));
       bp[n + 2] = off;
}

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static void squeeze_key ( uint16 sp,
const DBT key,
const DBT val 
) [static]

Definition at line 1229 of file h_page.c.

{
       register char *p;
       uint16 free_space, n, off, pageno;

       p = (char *)sp;
       n = sp[0];
       free_space = FREESPACE(sp);
       off = OFFSET(sp);

       pageno = sp[n - 1];
       off -= key->size;
       sp[n - 1] = off;
       memmove(p + off, key->data, key->size);
       off -= val->size;
       sp[n] = off;
       memmove(p + off, val->data, val->size);
       sp[0] = n + 2;
       sp[n + 1] = pageno;
       sp[n + 2] = OVFLPAGE;
       FREESPACE(sp) = free_space - PAIRSIZE(key, val);
       OFFSET(sp) = off;
}

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static int ugly_split ( HTAB hashp,
uint32  obucket,
BUFHEAD *  old_bufp,
BUFHEAD *  new_bufp,
int  copyto,
int  moved 
) [static]

Definition at line 409 of file h_page.c.

{
       register BUFHEAD *bufp;     /* Buffer header for ino */
       register uint16 *ino;       /* Page keys come off of */
       register uint16 *np; /* New page */
       register uint16 *op; /* Page keys go on to if they aren't moving */
    uint32 loop_detection=0;

       BUFHEAD *last_bfp;   /* Last buf header OVFL needing to be freed */
       DBT key, val;
       SPLIT_RETURN ret;
       uint16 n, off, ov_addr, scopyto;
       char *cino;          /* Character value of ino */
       int status;

       bufp = old_bufp;
       ino = (uint16 *)old_bufp->page;
       np = (uint16 *)new_bufp->page;
       op = (uint16 *)old_bufp->page;
       last_bfp = NULL;
       scopyto = (uint16)copyto;   /* ANSI */

       n = ino[0] - 1;
       while (n < ino[0]) {


        /* this function goes nuts sometimes and never returns. 
         * I havent found the problem yet but I need a solution
         * so if we loop too often we assume a database curruption error
         * :LJM
         */
        loop_detection++;

        if(loop_detection > MAX_UGLY_SPLIT_LOOPS)
            return DATABASE_CORRUPTED_ERROR;

              if (ino[2] < REAL_KEY && ino[2] != OVFLPAGE) {
                     if ((status = __big_split(hashp, old_bufp,
                         new_bufp, bufp, bufp->addr, obucket, &ret)))
                            return (status);
                     old_bufp = ret.oldp;
                     if (!old_bufp)
                            return (-1);
                     op = (uint16 *)old_bufp->page;
                     new_bufp = ret.newp;
                     if (!new_bufp)
                            return (-1);
                     np = (uint16 *)new_bufp->page;
                     bufp = ret.nextp;
                     if (!bufp)
                            return (0);
                     cino = (char *)bufp->page;
                     ino = (uint16 *)cino;
                     last_bfp = ret.nextp;
              } else if (ino[n + 1] == OVFLPAGE) {
                     ov_addr = ino[n];
                     /*
                      * Fix up the old page -- the extra 2 are the fields
                      * which contained the overflow information.
                      */
                     ino[0] -= (moved + 2);
                     FREESPACE(ino) =
                         scopyto - sizeof(uint16) * (ino[0] + 3);
                     OFFSET(ino) = scopyto;

                     bufp = __get_buf(hashp, ov_addr, bufp, 0);
                     if (!bufp)
                            return (-1);

                     ino = (uint16 *)bufp->page;
                     n = 1;
                     scopyto = hashp->BSIZE;
                     moved = 0;

                     if (last_bfp)
                            __free_ovflpage(hashp, last_bfp);
                     last_bfp = bufp;
              }
              /* Move regular sized pairs of there are any */
              off = hashp->BSIZE;
              for (n = 1; (n < ino[0]) && (ino[n + 1] >= REAL_KEY); n += 2) {
                     cino = (char *)ino;
                     key.data = (uint8 *)cino + ino[n];
                     key.size = off - ino[n];
                     val.data = (uint8 *)cino + ino[n + 1];
                     val.size = ino[n] - ino[n + 1];
                     off = ino[n + 1];

                     if (__call_hash(hashp, (char*)key.data, key.size) == obucket) {
                            /* Keep on old page */
                            if (PAIRFITS(op, (&key), (&val)))
                                   putpair((char *)op, &key, &val);
                            else {
                                   old_bufp =
                                       __add_ovflpage(hashp, old_bufp);
                                   if (!old_bufp)
                                          return (-1);
                                   op = (uint16 *)old_bufp->page;
                                   putpair((char *)op, &key, &val);
                            }
                            old_bufp->flags |= BUF_MOD;
                     } else {
                            /* Move to new page */
                            if (PAIRFITS(np, (&key), (&val)))
                                   putpair((char *)np, &key, &val);
                            else {
                                   new_bufp =
                                       __add_ovflpage(hashp, new_bufp);
                                   if (!new_bufp)
                                          return (-1);
                                   np = (uint16 *)new_bufp->page;
                                   putpair((char *)np, &key, &val);
                            }
                            new_bufp->flags |= BUF_MOD;
                     }
              }
       }
       if (last_bfp)
              __free_ovflpage(hashp, last_bfp);
       return (0);
}

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