/*
   Copyright (c) 2000, 2023, Oracle and/or its affiliates.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License, version 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
   02110-1301  USA */

/*
  Replace strings in textfile

  This program replaces strings in files or from stdin to stdout.
  It accepts a list of from-string/to-string pairs and replaces
  each occurrence of a from-string with the corresponding to-string.
  The first occurrence of a found string is matched. If there is more
  than one possibility for the string to replace, longer matches
  are preferred before shorter matches.

  Special characters in from string:
  \^    Match start of line.
  \$	Match end of line.
  \b	Match space-character, start of line or end of line.
        For end \b the next replace starts locking at the end space-character.
        An \b alone or in a string matches only a space-character.
  \r, \t, \v as in C.
  The programs make a DFA-state-machine of the strings and the speed isn't
  dependent on the count of replace-strings (only of the number of replaces).
  A line is assumed ending with \n or \0.
  There are no limit exept memory on length of strings.

  Written by Monty.
  fill_buffer_retaining() is taken from gnu-grep and modified.
*/

#include <my_global.h>
#include <m_ctype.h>
#include <my_sys.h>
#include <m_string.h>
#include <errno.h>

#define PC_MALLOC		256	/* Bytes for pointers */
#define PS_MALLOC		512	/* Bytes for data */

typedef struct st_pointer_array {		/* when using array-strings */
  TYPELIB typelib;				/* Pointer to strings */
  uchar *str;					/* Strings is here */
  uint8	*flag;					/* Flag about each var. */
  uint  array_allocs,max_count,length,max_length;
} POINTER_ARRAY;

#define SPACE_CHAR	256
#define START_OF_LINE	257
#define END_OF_LINE	258
#define LAST_CHAR_CODE	259

typedef struct st_replace {
  my_bool   found;
  struct st_replace *next[256];
} REPLACE;

typedef struct st_replace_found {
  my_bool found;
  char *replace_string;
  uint to_offset;
  int from_offset;
} REPLACE_STRING;

#ifndef WORD_BIT
#define WORD_BIT (8*sizeof(uint))
#endif

	/* functions defined in this file */

static int static_get_options(int *argc,char * * *argv);
static int get_replace_strings(int *argc,char * * *argv,
				   POINTER_ARRAY *from_array,
				   POINTER_ARRAY *to_array);
static int insert_pointer_name(POINTER_ARRAY *pa, char * name);
static void free_pointer_array(POINTER_ARRAY *pa);
static int convert_pipe(REPLACE *,FILE *,FILE *);
static int convert_file(REPLACE *, char *);
static REPLACE *init_replace(char * *from, char * *to,uint count,
                             char * word_end_chars);
static uint replace_strings(REPLACE *rep, char * *start,uint *max_length,
                            char * from);
static int initialize_buffer(void);
static void reset_buffer(void);
static void free_buffer(void);

static int silent=0,verbose=0,updated=0;

	/* The main program */

int main(int argc, char *argv[])
{
  int i,error;
  char word_end_chars[256],*pos;
  POINTER_ARRAY from,to;
  REPLACE *replace;

  fprintf(stderr, "Warning: replace is deprecated and will be removed in a "
          "future version.\n");

  MY_INIT(argv[0]);

  if (static_get_options(&argc,&argv))
    exit(1);
  if (get_replace_strings(&argc,&argv,&from,&to))
    exit(1);

  for (i=1,pos=word_end_chars ; i < 256 ; i++)
    if (my_isspace(&my_charset_latin1,i))
      *pos++= (char) i;
  *pos=0;
  if (!(replace=init_replace((char**) from.typelib.type_names,
			     (char**) to.typelib.type_names,
			     (uint) from.typelib.count,word_end_chars)))
    exit(1);
  free_pointer_array(&from);
  free_pointer_array(&to);
  if (initialize_buffer())
    return 1;

  error=0;
  if (argc == 0)
    error=convert_pipe(replace,stdin,stdout);
  else
  {
    while (argc--)
    {
      error=convert_file(replace,*(argv++));
    }
  }
  free_buffer();
  my_end(verbose ? MY_CHECK_ERROR | MY_GIVE_INFO : MY_CHECK_ERROR);
  exit(error ? 2 : 0);
  return 0;					/* No compiler warning */
} /* main */


	/* reads options */
	/* Initiates DEBUG - but no debugging here ! */

static int static_get_options(argc,argv)
int *argc;
char **argv[];
{
  int help,version;
  char *pos;

  silent=verbose=help=0;

  while (--*argc > 0 && *(pos = *(++*argv)) == '-' && pos[1] != '-') {
    while (*++pos)
    {
      version=0;
      switch((*pos)) {
      case 's':
	silent=1;
	break;
      case 'v':
	verbose=1;
	break;
      case '#':
	DBUG_PUSH (++pos);
	pos= (char*) " ";			/* Skip rest of arguments */
	break;
      case 'V':
	version=1;
        // Fall through.
      case 'I':
      case '?':
	help=1;					/* Help text written */
	printf("%s  Ver 1.4 for %s at %s\n",my_progname,SYSTEM_TYPE,
	       MACHINE_TYPE);
	if (version)
	  break;
	puts("This software comes with ABSOLUTELY NO WARRANTY. This is free software,\nand you are welcome to modify and redistribute it under the GPL license\n");
	puts("This program replaces strings in files or from stdin to stdout.\n"
	     "It accepts a list of from-string/to-string pairs and replaces\n"
	     "each occurrence of a from-string with the corresponding to-string.\n"
         "The first occurrence of a found string is matched. If there is\n"
         "more than one possibility for the string to replace, longer\n"
         "matches are preferred before shorter matches.\n\n"
	     "A from-string can contain these special characters:\n"
	     "  \\^      Match start of line.\n"
	     "  \\$      Match end of line.\n"
	     "  \\b      Match space-character, start of line or end of line.\n"
	     "          For a end \\b the next replace starts locking at the end\n"
	     "          space-character. A \\b alone in a string matches only a\n"
	     "          space-character.\n");
	  printf("Usage: %s [-?svIV] from to from to ... -- [files]\n", my_progname);
	puts("or");
	  printf("Usage: %s [-?svIV] from to from to ... < fromfile > tofile\n", my_progname);
	puts("");
	puts("Options: -? or -I \"Info\"  -s \"silent\"      -v \"verbose\"");
	break;
      default:
	fprintf(stderr,"illegal option: -%c\n",*pos);
	break;
      }
    }
  }
  if (*argc == 0)
  {
    if (!help)
      my_message(0,"No replace options given",MYF(0));
    exit(0);					/* Don't use as pipe */
  }
  return(0);
} /* static_get_options */


static int get_replace_strings(argc,argv,from_array,to_array)
int *argc;
char **argv[];
POINTER_ARRAY *from_array,*to_array;
{
  char *pos;

  memset(from_array, 0, sizeof(from_array[0]));
  memset(to_array, 0, sizeof(to_array[0]));
  while (*argc > 0 && (*(pos = *(*argv)) != '-' || pos[1] != '-' || pos[2]))
  {
    insert_pointer_name(from_array,pos);
    (*argc)--;
    (*argv)++;
    if (!*argc || !strcmp(**argv,"--"))
    {
      my_message(0,"No to-string for last from-string",MYF(0));
      return 1;
    }
    insert_pointer_name(to_array,**argv);
    (*argc)--;
    (*argv)++;
  }
  if (*argc)
  {					/* Skip "--" argument */
    (*argc)--;
    (*argv)++;
  }
  return 0;
}

static int insert_pointer_name(POINTER_ARRAY *pa,char * name)
{
  uint i,length,old_count;
  uchar *new_pos;
  const char **new_array;
  DBUG_ENTER("insert_pointer_name");

  if (! pa->typelib.count)
  {
    if (!(pa->typelib.type_names=(const char **)
	  my_malloc(PSI_NOT_INSTRUMENTED,
                    ((PC_MALLOC-MALLOC_OVERHEAD)/
		     (sizeof(char *)+sizeof(*pa->flag))*
		     (sizeof(char *)+sizeof(*pa->flag))),MYF(MY_WME))))
      DBUG_RETURN(-1);
    if (!(pa->str= (uchar*) my_malloc(PSI_NOT_INSTRUMENTED,
                                      (uint) (PS_MALLOC-MALLOC_OVERHEAD),
				     MYF(MY_WME))))
    {
      my_free((char**)pa->typelib.type_names);
      DBUG_RETURN (-1);
    }
    pa->max_count=(PC_MALLOC-MALLOC_OVERHEAD)/(sizeof(uchar*)+
					       sizeof(*pa->flag));
    pa->flag= (uint8*) (pa->typelib.type_names+pa->max_count);
    pa->length=0;
    pa->max_length=PS_MALLOC-MALLOC_OVERHEAD;
    pa->array_allocs=1;
  }
  length=(uint) strlen(name)+1;
  if (pa->length+length >= pa->max_length)
  {
    pa->max_length=(pa->length+length+MALLOC_OVERHEAD+PS_MALLOC-1)/PS_MALLOC;
    pa->max_length=pa->max_length*PS_MALLOC-MALLOC_OVERHEAD;
    if (!(new_pos= (uchar*) my_realloc(PSI_NOT_INSTRUMENTED,
                                       (uchar*) pa->str,
				      (uint) pa->max_length,
				      MYF(MY_WME))))
      DBUG_RETURN(1);
    if (new_pos != pa->str)
    {
      my_ptrdiff_t diff=PTR_BYTE_DIFF(new_pos,pa->str);
      for (i=0 ; i < pa->typelib.count ; i++)
	pa->typelib.type_names[i]= ADD_TO_PTR(pa->typelib.type_names[i],diff,
					      char*);
      pa->str=new_pos;
    }
  }
  if (pa->typelib.count >= pa->max_count-1)
  {
    int len;
    pa->array_allocs++;
    len=(PC_MALLOC*pa->array_allocs - MALLOC_OVERHEAD);
    if (!(new_array=(const char **) my_realloc(PSI_NOT_INSTRUMENTED,
                                               (uchar*) pa->typelib.type_names,
					       (uint) len/
					 (sizeof(uchar*)+sizeof(*pa->flag))*
					 (sizeof(uchar*)+sizeof(*pa->flag)),
					 MYF(MY_WME))))
      DBUG_RETURN(1);
    pa->typelib.type_names=new_array;
    old_count=pa->max_count;
    pa->max_count=len/(sizeof(uchar*) + sizeof(*pa->flag));
    pa->flag= (uint8*) (pa->typelib.type_names+pa->max_count);
    memcpy((uchar*) pa->flag,(char *) (pa->typelib.type_names+old_count),
	   old_count*sizeof(*pa->flag));
  }
  pa->flag[pa->typelib.count]=0;			/* Reset flag */
  pa->typelib.type_names[pa->typelib.count++]= (char*) (pa->str+pa->length);
  pa->typelib.type_names[pa->typelib.count]= NullS;	/* Put end-mark */
  (void) my_stpcpy((char*) pa->str + pa->length, name);
  pa->length+=length;
  DBUG_RETURN(0);
} /* insert_pointer_name */


	/* free pointer array */

static void free_pointer_array(POINTER_ARRAY *pa)
{
  if (pa->typelib.count)
  {
    pa->typelib.count=0;
    my_free((char**)pa->typelib.type_names);
    pa->typelib.type_names=0;
    my_free(pa->str);
  }
  return;
} /* free_pointer_array */


	/* Code for replace rutines */

#define SET_MALLOC_HUNC 64

typedef struct st_rep_set {
  uint  *bits;				/* Pointer to used sets */
  short	next[LAST_CHAR_CODE];		/* Pointer to next sets */
  uint	found_len;			/* Best match to date */
  int	found_offset;
  uint  table_offset;
  uint  size_of_bits;			/* For convinience */
} REP_SET;

typedef struct st_rep_sets {
  uint		count;			/* Number of sets */
  uint		extra;			/* Extra sets in buffer */
  uint		invisible;		/* Sets not chown */
  uint		size_of_bits;
  REP_SET	*set,*set_buffer;
  uint		*bit_buffer;
} REP_SETS;

typedef struct st_found_set {
  uint table_offset;
  int found_offset;
} FOUND_SET;

typedef struct st_follow {
  int chr;
  uint table_offset;
  uint len;
} FOLLOWS;


static int init_sets(REP_SETS *sets,uint states);
static REP_SET *make_new_set(REP_SETS *sets);
static void make_sets_invisible(REP_SETS *sets);
static void free_last_set(REP_SETS *sets);
static void free_sets(REP_SETS *sets);
static void internal_set_bit(REP_SET *set, uint bit);
static void internal_clear_bit(REP_SET *set, uint bit);
static void or_bits(REP_SET *to,REP_SET *from);
static void copy_bits(REP_SET *to,REP_SET *from);
static int cmp_bits(REP_SET *set1,REP_SET *set2);
static int get_next_bit(REP_SET *set,uint lastpos);
static short find_set(REP_SETS *sets,REP_SET *find);
static short find_found(FOUND_SET *found_set,uint table_offset,
                        int found_offset);
static uint start_at_word(char * pos);
static uint end_of_word(char * pos);
static uint replace_len(char * pos);

static uint found_sets=0;


	/* Init a replace structure for further calls */

static REPLACE *init_replace(char * *from, char * *to,uint count,
                             char * word_end_chars)
{
  uint i,j,states,set_nr,len,result_len,max_length,found_end,bits_set,bit_nr;
  int used_sets,chr;
  short default_state;
  char used_chars[LAST_CHAR_CODE],is_word_end[256];
  char * pos, *to_pos, **to_array;
  REP_SETS sets;
  REP_SET *set,*start_states,*word_states,*new_set;
  FOLLOWS *follow,*follow_ptr;
  REPLACE *replace;
  FOUND_SET *found_set;
  REPLACE_STRING *rep_str;
  DBUG_ENTER("init_replace");

  /* Count number of states */
  for (i=result_len=max_length=0 , states=2 ; i < count ; i++)
  {
    len=replace_len(from[i]);
    if (!len)
    {
      errno=EINVAL;
      my_message(0,"No to-string for last from-string",MYF(0));
      DBUG_RETURN(0);
    }
    states+=len+1;
    result_len+=(uint) strlen(to[i])+1;
    if (len > max_length)
      max_length=len;
  }
  memset(is_word_end, 0, sizeof(is_word_end));
  for (i=0 ; word_end_chars[i] ; i++)
    is_word_end[(uchar) word_end_chars[i]]=1;

  if (init_sets(&sets,states))
    DBUG_RETURN(0);
  found_sets=0;
  if (!(found_set= (FOUND_SET*) my_malloc(PSI_NOT_INSTRUMENTED,
                                          sizeof(FOUND_SET)*max_length*count,
					  MYF(MY_WME))))
  {
    free_sets(&sets);
    DBUG_RETURN(0);
  }
  (void) make_new_set(&sets);			/* Set starting set */
  make_sets_invisible(&sets);			/* Hide previus sets */
  used_sets=-1;
  word_states=make_new_set(&sets);		/* Start of new word */
  start_states=make_new_set(&sets);		/* This is first state */
  if (!(follow=(FOLLOWS*) my_malloc(PSI_NOT_INSTRUMENTED,
                                    (states+2)*sizeof(FOLLOWS),MYF(MY_WME))))
  {
    free_sets(&sets);
    my_free(found_set);
    DBUG_RETURN(0);
  }

	/* Init follow_ptr[] */
  for (i=0, states=1, follow_ptr=follow+1 ; i < count ; i++)
  {
    if (from[i][0] == '\\' && from[i][1] == '^')
    {
      internal_set_bit(start_states,states+1);
      if (!from[i][2])
      {
	start_states->table_offset=i;
	start_states->found_offset=1;
      }
    }
    else if (from[i][0] == '\\' && from[i][1] == '$')
    {
      internal_set_bit(start_states,states);
      internal_set_bit(word_states,states);
      if (!from[i][2] && start_states->table_offset == (uint) ~0)
      {
	start_states->table_offset=i;
	start_states->found_offset=0;
      }
    }
    else
    {
      internal_set_bit(word_states,states);
      if (from[i][0] == '\\' && (from[i][1] == 'b' && from[i][2]))
	internal_set_bit(start_states,states+1);
      else
	internal_set_bit(start_states,states);
    }
    for (pos=from[i], len=0; *pos ; pos++)
    {
      if (*pos == '\\' && *(pos+1))
      {
	pos++;
	switch (*pos) {
	case 'b':
	  follow_ptr->chr = SPACE_CHAR;
	  break;
	case '^':
	  follow_ptr->chr = START_OF_LINE;
	  break;
	case '$':
	  follow_ptr->chr = END_OF_LINE;
	  break;
	case 'r':
	  follow_ptr->chr = '\r';
	  break;
	case 't':
	  follow_ptr->chr = '\t';
	  break;
	case 'v':
	  follow_ptr->chr = '\v';
	  break;
	default:
	  follow_ptr->chr = (uchar) *pos;
	  break;
	}
      }
      else
	follow_ptr->chr= (uchar) *pos;
      follow_ptr->table_offset=i;
      follow_ptr->len= ++len;
      follow_ptr++;
    }
    follow_ptr->chr=0;
    follow_ptr->table_offset=i;
    follow_ptr->len=len;
    follow_ptr++;
    states+=(uint) len+1;
  }


  for (set_nr=0,pos=0 ; set_nr < sets.count ; set_nr++)
  {
    set=sets.set+set_nr;
    default_state= 0;				/* Start from beginning */

    /* If end of found-string not found or start-set with current set */

    for (i= (uint) ~0; (i=get_next_bit(set,i)) ;)
    {
      if (!follow[i].chr)
      {
	if (! default_state)
	  default_state= find_found(found_set,set->table_offset,
				    set->found_offset+1);
      }
    }
    copy_bits(sets.set+used_sets,set);		/* Save set for changes */
    if (!default_state)
      or_bits(sets.set+used_sets,sets.set);	/* Can restart from start */

    /* Find all chars that follows current sets */
    memset(used_chars, 0, sizeof(used_chars));
    for (i= (uint) ~0; (i=get_next_bit(sets.set+used_sets,i)) ;)
    {
      used_chars[follow[i].chr]=1;
      if ((follow[i].chr == SPACE_CHAR && !follow[i+1].chr &&
	   follow[i].len > 1) || follow[i].chr == END_OF_LINE)
	used_chars[0]=1;
    }

    /* Mark word_chars used if \b is in state */
    if (used_chars[SPACE_CHAR])
      for (pos= word_end_chars ; *pos ; pos++)
	used_chars[(int) (uchar) *pos] = 1;

    /* Handle other used characters */
    for (chr= 0 ; chr < 256 ; chr++)
    {
      if (! used_chars[chr])
	set->next[chr]= (short) (chr ? default_state : -1);
      else
      {
	new_set=make_new_set(&sets);
	set=sets.set+set_nr;			/* if realloc */
	new_set->table_offset=set->table_offset;
	new_set->found_len=set->found_len;
	new_set->found_offset=set->found_offset+1;
	found_end=0;

	for (i= (uint) ~0 ; (i=get_next_bit(sets.set+used_sets,i)) ; )
	{
	  if (!follow[i].chr || follow[i].chr == chr ||
	      (follow[i].chr == SPACE_CHAR &&
	       (is_word_end[chr] ||
		(!chr && follow[i].len > 1 && ! follow[i+1].chr))) ||
	      (follow[i].chr == END_OF_LINE && ! chr))
	  {
	    if ((! chr || (follow[i].chr && !follow[i+1].chr)) &&
		follow[i].len > found_end)
	      found_end=follow[i].len;
	    if (chr && follow[i].chr)
	      internal_set_bit(new_set,i+1);		/* To next set */
	    else
	      internal_set_bit(new_set,i);
	  }
	}
	if (found_end)
	{
	  new_set->found_len=0;			/* Set for testing if first */
	  bits_set=0;
	  for (i= (uint) ~0; (i=get_next_bit(new_set,i)) ;)
	  {
	    if ((follow[i].chr == SPACE_CHAR ||
		 follow[i].chr == END_OF_LINE) && ! chr)
	      bit_nr=i+1;
	    else
	      bit_nr=i;
	    if (follow[bit_nr-1].len < found_end ||
		(new_set->found_len &&
		 (chr == 0 || !follow[bit_nr].chr)))
	      internal_clear_bit(new_set,i);
	    else
	    {
	      if (chr == 0 || !follow[bit_nr].chr)
	      {					/* best match  */
		new_set->table_offset=follow[bit_nr].table_offset;
		if (chr || (follow[i].chr == SPACE_CHAR ||
			    follow[i].chr == END_OF_LINE))
		  new_set->found_offset=found_end;	/* New match */
		new_set->found_len=found_end;
	      }
	      bits_set++;
	    }
	  }
	  if (bits_set == 1)
	  {
	    set->next[chr] = find_found(found_set,
					new_set->table_offset,
					new_set->found_offset);
	    free_last_set(&sets);
	  }
	  else
	    set->next[chr] = find_set(&sets,new_set);
	}
	else
	  set->next[chr] = find_set(&sets,new_set);
      }
    }
  }

	/* Alloc replace structure for the replace-state-machine */

  if ((replace=(REPLACE*) my_malloc(PSI_NOT_INSTRUMENTED,
                                    sizeof(REPLACE)*(sets.count)+
				    sizeof(REPLACE_STRING)*(found_sets+1)+
				    sizeof(char *)*count+result_len,
				    MYF(MY_WME | MY_ZEROFILL))))
  {
    rep_str=(REPLACE_STRING*) (replace+sets.count);
    to_array=(char **) (rep_str+found_sets+1);
    to_pos=(char *) (to_array+count);
    for (i=0 ; i < count ; i++)
    {
      to_array[i]=to_pos;
      to_pos=my_stpcpy(to_pos,to[i])+1;
    }
    rep_str[0].found=1;
    rep_str[0].replace_string=0;
    for (i=1 ; i <= found_sets ; i++)
    {
      pos=from[found_set[i-1].table_offset];
      rep_str[i].found= (my_bool) (!memcmp(pos,"\\^",3) ? 2 : 1);
      rep_str[i].replace_string=to_array[found_set[i-1].table_offset];
      rep_str[i].to_offset=found_set[i-1].found_offset-start_at_word(pos);
      rep_str[i].from_offset=found_set[i-1].found_offset-replace_len(pos)+
	end_of_word(pos);
    }
    for (i=0 ; i < sets.count ; i++)
    {
      for (j=0 ; j < 256 ; j++)
	if (sets.set[i].next[j] >= 0)
	  replace[i].next[j]=replace+sets.set[i].next[j];
	else
	  replace[i].next[j]=(REPLACE*) (rep_str+(-sets.set[i].next[j]-1));
    }
  }
  my_free(follow);
  free_sets(&sets);
  my_free(found_set);
  DBUG_PRINT("exit",("Replace table has %d states",sets.count));
  DBUG_RETURN(replace);
}


static int init_sets(REP_SETS *sets,uint states)
{
  memset(sets, 0, sizeof(*sets));
  sets->size_of_bits=((states+7)/8);
  if (!(sets->set_buffer=(REP_SET*) my_malloc(PSI_NOT_INSTRUMENTED,
                                              sizeof(REP_SET)*SET_MALLOC_HUNC,
					      MYF(MY_WME))))
    return 1;
  if (!(sets->bit_buffer=(uint*) my_malloc(PSI_NOT_INSTRUMENTED,
                                           sizeof(uint)*sets->size_of_bits*
					   SET_MALLOC_HUNC,MYF(MY_WME))))
  {
    my_free(sets->set);
    return 1;
  }
  return 0;
}

	/* Make help sets invisible for nicer codeing */

static void make_sets_invisible(REP_SETS *sets)
{
  sets->invisible=sets->count;
  sets->set+=sets->count;
  sets->count=0;
}

static REP_SET *make_new_set(REP_SETS *sets)
{
  uint i,count,*bit_buffer;
  REP_SET *set;
  if (sets->extra)
  {
    sets->extra--;
    set=sets->set+ sets->count++;
    memset(set->bits, 0, sizeof(uint)*sets->size_of_bits);
    memset(&set->next[0], 0, sizeof(set->next[0])*LAST_CHAR_CODE);
    set->found_offset=0;
    set->found_len=0;
    set->table_offset= (uint) ~0;
    set->size_of_bits=sets->size_of_bits;
    return set;
  }
  count=sets->count+sets->invisible+SET_MALLOC_HUNC;
  if (!(set=(REP_SET*) my_realloc(PSI_NOT_INSTRUMENTED,
                                  (uchar*) sets->set_buffer,
				   sizeof(REP_SET)*count,
				  MYF(MY_WME))))
    return 0;
  sets->set_buffer=set;
  sets->set=set+sets->invisible;
  if (!(bit_buffer=(uint*) my_realloc(PSI_NOT_INSTRUMENTED,
                                      (uchar*) sets->bit_buffer,
				      (sizeof(uint)*sets->size_of_bits)*count,
				      MYF(MY_WME))))
    return 0;
  sets->bit_buffer=bit_buffer;
  for (i=0 ; i < count ; i++)
  {
    sets->set_buffer[i].bits=bit_buffer;
    bit_buffer+=sets->size_of_bits;
  }
  sets->extra=SET_MALLOC_HUNC;
  return make_new_set(sets);
}

static void free_last_set(REP_SETS *sets)
{
  sets->count--;
  sets->extra++;
  return;
}

static void free_sets(REP_SETS *sets)
{
  my_free(sets->set_buffer);
  my_free(sets->bit_buffer);
  return;
}

static void internal_set_bit(REP_SET *set, uint bit)
{
  set->bits[bit / WORD_BIT] |= 1 << (bit % WORD_BIT);
  return;
}

static void internal_clear_bit(REP_SET *set, uint bit)
{
  set->bits[bit / WORD_BIT] &= ~ (1 << (bit % WORD_BIT));
  return;
}


static void or_bits(REP_SET *to,REP_SET *from)
{
  uint i;
  for (i=0 ; i < to->size_of_bits ; i++)
    to->bits[i]|=from->bits[i];
  return;
}

static void copy_bits(REP_SET *to,REP_SET *from)
{
  memcpy((uchar*) to->bits,(uchar*) from->bits,
	 (size_t) (sizeof(uint) * to->size_of_bits));
}

static int cmp_bits(REP_SET *set1,REP_SET *set2)
{
  return memcmp(set1->bits, set2->bits,
                sizeof(uint) * set1->size_of_bits);
}


	/* Get next set bit from set. */

static int get_next_bit(REP_SET *set,uint lastpos)
{
  uint pos,*start,*end,bits;

  start=set->bits+ ((lastpos+1) / WORD_BIT);
  end=set->bits + set->size_of_bits;
  bits=start[0] & ~((1 << ((lastpos+1) % WORD_BIT)) -1);

  while (! bits && ++start < end)
    bits=start[0];
  if (!bits)
    return 0;
  pos=(uint) (start-set->bits)*WORD_BIT;
  while (! (bits & 1))
  {
    bits>>=1;
    pos++;
  }
  return pos;
}

	/* find if there is a same set in sets. If there is, use it and
	   free given set, else put in given set in sets and return it's
	   position */

static short find_set(REP_SETS *sets,REP_SET *find)
{
  uint i;
  for (i=0 ; i < sets->count-1 ; i++)
  {
    if (!cmp_bits(sets->set+i,find))
    {
      free_last_set(sets);
      return (short) i;
    }
  }
  return (short) i;			/* return new position */
}


/*
  find if there is a found_set with same table_offset & found_offset
  If there is return offset to it, else add new offset and return pos.
  Pos returned is -offset-2 in found_set_structure because it's is
  saved in set->next and set->next[] >= 0 points to next set and
  set->next[] == -1 is reserved for end without replaces.
*/

static short find_found(FOUND_SET *found_set,uint table_offset,
                        int found_offset)
{
  int i;
  for (i=0 ; (uint) i < found_sets ; i++)
    if (found_set[i].table_offset == table_offset &&
	found_set[i].found_offset == found_offset)
      return (short) (-i-2);
  found_set[i].table_offset=table_offset;
  found_set[i].found_offset=found_offset;
  found_sets++;
  return (short) (-i-2);			/* return new position */
}

	/* Return 1 if regexp starts with \b or ends with \b*/

static uint start_at_word(char * pos)
{
  return (((!memcmp(pos,"\\b",2) && pos[2]) || !memcmp(pos,"\\^",2)) ? 1 : 0);
}

static uint end_of_word(char * pos)
{
  char * end=strend(pos);
  return ((end > pos+2 && !memcmp(end-2,"\\b",2)) ||
	  (end >= pos+2 && !memcmp(end-2,"\\$",2))) ?
	    1 : 0;
}


static uint replace_len(char * str)
{
  uint len=0;
  while (*str)
  {
    if (str[0] == '\\' && str[1])
      str++;
    str++;
    len++;
  }
  return len;
}


	/* The actual loop */

static uint replace_strings(REPLACE *rep, char **start, uint *max_length,
                            char *from)
{
  REPLACE *rep_pos;
  REPLACE_STRING *rep_str;
  char *to, *end, *pos, *new;

  end=(to= *start) + *max_length-1;
  rep_pos=rep+1;
  for(;;)
  {
    while (!rep_pos->found)
    {
      rep_pos= rep_pos->next[(uchar) *from];
      if (to == end)
      {
	(*max_length)+=8192;
	if (!(new=my_realloc(PSI_NOT_INSTRUMENTED,
                             *start,*max_length,MYF(MY_WME))))
	  return (uint) -1;
	to=new+(to - *start);
	end=(*start=new)+ *max_length-1;
      }
      *to++= *from++;
    }
    if (!(rep_str = ((REPLACE_STRING*) rep_pos))->replace_string)
      return (uint) (to - *start)-1;
    updated=1;			/* Some char * is replaced */
    to-=rep_str->to_offset;
    for (pos=rep_str->replace_string; *pos ; pos++)
    {
      if (to == end)
      {
	(*max_length)*=2;
	if (!(new=my_realloc(PSI_NOT_INSTRUMENTED,
                             *start,*max_length,MYF(MY_WME))))
	  return (uint) -1;
	to=new+(to - *start);
	end=(*start=new)+ *max_length-1;
      }
      *to++= *pos;
    }
    if (!*(from-=rep_str->from_offset) && rep_pos->found != 2)
      return (uint) (to - *start);
    rep_pos=rep;
  }
}

static char *buffer;		/* The buffer itself, grown as needed. */
static int bufbytes;		/* Number of bytes in the buffer. */
static int bufread,my_eof;		/* Number of bytes to get with each read(). */
static uint bufalloc;
static char *out_buff;
static uint out_length;

static int initialize_buffer()
{
  bufread = 8192;
  bufalloc = bufread + bufread / 2;
  if (!(buffer = my_malloc(PSI_NOT_INSTRUMENTED,
                           bufalloc+1,MYF(MY_WME))))
    return 1;
  bufbytes=my_eof=0;
  out_length=bufread;
  if (!(out_buff=my_malloc(PSI_NOT_INSTRUMENTED,
                           out_length,MYF(MY_WME))))
    return(1);
  return 0;
}

static void reset_buffer()
{
  bufbytes=my_eof=0;
}

static void free_buffer()
{
  my_free(buffer);
  my_free(out_buff);
}


/*
  Fill the buffer retaining the last n bytes at the beginning of the
  newly filled buffer (for backward context).  Returns the number of new
  bytes read from disk.
*/

static int fill_buffer_retaining(fd,n)
File fd;
int n;
{
  int i;

  /* See if we need to grow the buffer. */
  if ((int) bufalloc - n <= bufread)
  {
    while ((int) bufalloc - n <= bufread)
    {
      bufalloc *= 2;
      bufread *= 2;
    }
    buffer = my_realloc(PSI_NOT_INSTRUMENTED,
                        buffer, bufalloc+1, MYF(MY_WME));
    if (! buffer)
      return(-1);
  }

  /* Shift stuff down. */
  memmove(buffer, buffer+bufbytes-n, (uint) n);
  bufbytes = n;

  if (my_eof)
    return 0;

  /* Read in new stuff. */
  if ((i=(int) my_read(fd, (uchar*) buffer + bufbytes,
                       (size_t) bufread, MYF(MY_WME))) < 0)
    return -1;

  /* Kludge to pretend every nonempty file ends with a newline. */
  if (i == 0 && bufbytes > 0 && buffer[bufbytes - 1] != '\n')
  {
    my_eof = i = 1;
    buffer[bufbytes] = '\n';
  }

  bufbytes += i;
  return i;
}

	/* Return 0 if convert is ok */
	/* Global variable update is set if something was changed */

static int convert_pipe(rep,in,out)
REPLACE *rep;
FILE *in,*out;
{
  int retain,error;
  uint length;
  char save_char,*end_of_line,*start_of_line;
  DBUG_ENTER("convert_pipe");

  updated=retain=0;
  reset_buffer();

  while ((error=fill_buffer_retaining(my_fileno(in),retain)) > 0)
  {
    end_of_line=buffer ;
    buffer[bufbytes]=0;			/* Sentinel  */
    for (;;)
    {
      start_of_line=end_of_line;
      while (end_of_line[0] != '\n' && end_of_line[0])
	end_of_line++;
      if (end_of_line == buffer+bufbytes)
      {
	retain= (int) (end_of_line - start_of_line);
	break;				/* No end of line, read more */
      }
      save_char=end_of_line[0];
      end_of_line[0]=0;
      end_of_line++;
      if ((length=replace_strings(rep,&out_buff,&out_length,start_of_line)) ==
	  (uint) -1)
	DBUG_RETURN(1);
      if (!my_eof)
	out_buff[length++]=save_char;	/* Don't write added newline */
      if (my_fwrite(out, (uchar*) out_buff, length, MYF(MY_WME | MY_NABP)))
	DBUG_RETURN(1);
    }
  }
  DBUG_RETURN(error);
}


static int convert_file(REPLACE *rep, char * name)
{
  int error;
  FILE *in,*out;
  char dir_buff[FN_REFLEN], tempname[FN_REFLEN], *org_name = name;
#ifdef HAVE_READLINK
  char link_name[FN_REFLEN];
#endif
  File temp_file;
  size_t dir_buff_length;
  DBUG_ENTER("convert_file");

  /* check if name is a symlink */
#ifdef HAVE_READLINK  
  org_name= (my_enable_symlinks &&
             !my_readlink(link_name, name, MYF(0))) ? link_name : name;
#endif
  if (!(in= my_fopen(org_name,O_RDONLY,MYF(MY_WME))))
    DBUG_RETURN(1);
  dirname_part(dir_buff, org_name, &dir_buff_length);
  if ((temp_file= create_temp_file(tempname, dir_buff, "PR", O_WRONLY,
                                   MYF(MY_WME))) < 0)
  {
    my_fclose(in,MYF(0));
    DBUG_RETURN(1);
  }    
  if (!(out= my_fdopen(temp_file, tempname, O_WRONLY, MYF(MY_WME))))
  {
    my_fclose(in,MYF(0));
    DBUG_RETURN(1);
  }

  error=convert_pipe(rep,in,out);
  my_fclose(in,MYF(0)); my_fclose(out,MYF(0));

  if (updated && ! error)
    my_redel(org_name,tempname,MYF(MY_WME | MY_LINK_WARNING));
  else
    my_delete(tempname,MYF(MY_WME));
  if (!silent && ! error)
  {
    if (updated)
      printf("%s converted\n",name);
    else if (verbose)
      printf("%s left unchanged\n",name);
  }
  DBUG_RETURN(error);
}