/* basic cdb creation routines * * This file is a part of tinycdb package by Michael Tokarev, mjt@corpit.ru. * Public domain. */#include "common/setup_before.h"#include <stdio.h>#ifdef STDC_HEADERS# include <stdlib.h>#else# ifdef HAVE_MALLOC_H#  include <malloc.h># endif#endif#ifdef HAVE_STRING_H# include <string.h>#else# ifdef HAVE_STRINGS_H#  include <strings.h># endif# ifdef HAVE_MEMORY_H#  include <memory.h># endif#endif#include "common/xalloc.h"#include "cdb_int.h"#include "common/setup_after.h"voidcdb_pack(unsigned num, unsigned char buf[4]){  buf[0] = num & 255; num >>= 8;  buf[1] = num & 255; num >>= 8;  buf[2] = num & 255;  buf[3] = num >> 8;}intcdb_make_start(struct cdb_make *cdbmp, FILE *fd){  memset(cdbmp, 0, sizeof(*cdbmp));  cdbmp->cdb_fd = fd;  cdbmp->cdb_dpos = 2048;  cdbmp->cdb_bpos = cdbmp->cdb_buf + 2048;  return 0;}static intewrite(FILE *fd, const char *buf, int len){  while(len) {    int l = fwrite(buf, 1, len, fd);    if (l < 0 && errno != EINTR)      return -1;    len -= l;    buf += l;  }  return 0;}int_cdb_make_write(struct cdb_make *cdbmp, const char *ptr, unsigned len){  unsigned l = sizeof(cdbmp->cdb_buf) - (cdbmp->cdb_bpos - cdbmp->cdb_buf);  cdbmp->cdb_dpos += len;  if (len > l) {    memcpy(cdbmp->cdb_bpos, ptr, l);    if (ewrite(cdbmp->cdb_fd, cdbmp->cdb_buf, sizeof(cdbmp->cdb_buf)) < 0)      return -1;    ptr += l; len -= l;    l = len / sizeof(cdbmp->cdb_buf);    if (l) {      l *= sizeof(cdbmp->cdb_buf);      if (ewrite(cdbmp->cdb_fd, ptr, l) < 0)	return -1;      ptr += l; len -= l;    }    cdbmp->cdb_bpos = cdbmp->cdb_buf;  }  if (len) {    memcpy(cdbmp->cdb_bpos, ptr, len);    cdbmp->cdb_bpos += len;  }  return 0;}static intcdb_make_finish_internal(struct cdb_make *cdbmp){  unsigned hcnt[256];		/* hash table counts */  unsigned hpos[256];		/* hash table positions */  struct cdb_rec *htab;  unsigned char *p;  struct cdb_rl *rl;  unsigned hsize;  unsigned t, i;  if (((0xffffffff - cdbmp->cdb_dpos) >> 3) < cdbmp->cdb_rcnt)    return errno = ENOMEM, -1;  /* count htab sizes and reorder reclists */  hsize = 0;  for (t = 0; t < 256; ++t) {    struct cdb_rl *rlt = NULL;    i = 0;    rl = cdbmp->cdb_rec[t];    while(rl) {      struct cdb_rl *rln = rl->next;      rl->next = rlt;      rlt = rl;      i += rl->cnt;      rl = rln;    }    cdbmp->cdb_rec[t] = rlt;    if (hsize < (hcnt[t] = i << 1))      hsize = hcnt[t];  }  /* allocate memory to hold max htable */  htab = (struct cdb_rec*)xmalloc((hsize + 2) * sizeof(struct cdb_rec));  if (!htab)    return errno = ENOENT, -1;  p = (unsigned char *)htab;  htab += 2;  /* build hash tables */  for (t = 0; t < 256; ++t) {    unsigned len, hi;    hpos[t] = cdbmp->cdb_dpos;    if ((len = hcnt[t]) == 0)      continue;    for (i = 0; i < len; ++i)      htab[i].hval = htab[i].rpos = 0;    for (rl = cdbmp->cdb_rec[t]; rl; rl = rl->next)      for (i = 0; i < rl->cnt; ++i) {	hi = (rl->rec[i].hval >> 8) % len;	while(htab[hi].rpos)	  if (++hi == len)	    hi = 0;	htab[hi] = rl->rec[i];      }    for (i = 0; i < len; ++i) {      cdb_pack(htab[i].hval, p + (i << 3));      cdb_pack(htab[i].rpos, p + (i << 3) + 4);    }    if (_cdb_make_write(cdbmp, p, len << 3) < 0) {      xfree(p);      return -1;    }  }  xfree(p);  if (cdbmp->cdb_bpos != cdbmp->cdb_buf &&      ewrite(cdbmp->cdb_fd, cdbmp->cdb_buf,	     cdbmp->cdb_bpos - cdbmp->cdb_buf) != 0)      return -1;  p = cdbmp->cdb_buf;  for (t = 0; t < 256; ++t) {    cdb_pack(hpos[t], p + (t << 3));    cdb_pack(hcnt[t], p + (t << 3) + 4);  }  rewind(cdbmp->cdb_fd);  if (ewrite(cdbmp->cdb_fd, p, 2048) != 0)    return -1;  return 0;}static voidcdb_make_free(struct cdb_make *cdbmp){  unsigned t;  for(t = 0; t < 256; ++t) {    struct cdb_rl *rl = cdbmp->cdb_rec[t];    while(rl) {      struct cdb_rl *tm = rl;      rl = rl->next;      xfree(tm);    }  }}intcdb_make_finish(struct cdb_make *cdbmp){  int r = cdb_make_finish_internal(cdbmp);  cdb_make_free(cdbmp);  return r;}