/* filter2.c - Don Yang (uguu.org)

   05/11/02
                                                                           */

#include<stdio.h>
#include<stdlib.h>
#include<string.h>

#define Err(_) fprintf(stderr, "%s\n", text[_])
static char *text[6] =
   {"malloc", "open", "create", "write", "remove", "rename"};

int main(int argc, char **argv)
{
   FILE *infile, *outfile;
   char tmpname[16], *buffer, *tmpbuffer;
   int status, i, c;
   size_t bufsize, bufindex;

   i = 0;
   infile = stdin;
   outfile = stdout;
   if( argc > 1 )
   {
      if( strcmp(argv[1], "-") != 0 )
      {
         if( (infile = fopen(argv[1], "rb")) == NULL )
            return Err(1);
      }
      if( argc > 2 )
      {
         if( infile != stdin && strcmp(argv[1], argv[2]) == 0 )
         {
            for(i = 1; i < 999; i++)
            {
               sprintf(tmpname, "tmp.%d", i);
               if( (outfile = fopen(tmpname, "rb")) == NULL )
               {
                  if( (outfile = fopen(tmpname, "wb+")) != NULL )
                     i = 1000;
               }
            }
            if( i == 999 )
            {
               Err(2);
               fclose(infile);
               return 1;
            }
         }
         else
         {
            if( (outfile = fopen(argv[2], "wb+")) == NULL )
               return Err(2);
         }
      }
   }

   if( (buffer = (char*)malloc(bufsize = 256)) == NULL )
   {
      Err(0);
      status = 1;
   }
   else
   {
      bufindex = 0;
      status = 0;
      while( (c = fgetc(infile)) != EOF && status == 0 )
      {
         if( c == 13 || c == 10 )
         {
            if( fputc(c, outfile) == EOF )
            {
               Err(3);
               free(buffer);
               status = 1;
            }
            bufindex = 0;
         }
         else if( c == 32 || c == 9 )
         {
            buffer[bufindex++] = (char)c;
            if( bufindex >= bufsize )
            {
               tmpbuffer = (char*)realloc(buffer, bufsize *= 2);
               if( tmpbuffer == NULL )
               {
                  if( (tmpbuffer = (char*)malloc(bufsize)) == NULL )
                  {
                     Err(0);
                     free(buffer);
                     status = 1;
                  }
                  else
                  {
                     memcpy(tmpbuffer, buffer, bufsize / 2);
                     free(buffer);
                     buffer = tmpbuffer;
                  }
               }
            }
         }
         else
         {
            if( bufindex > 0 )
            {
               if( fwrite(buffer, bufindex, 1, outfile) != 1 )
               {
                  Err(3);
                  free(buffer);
                  status = 1;
               }
               bufindex = 0;
            }
            if( fputc(c, outfile) == EOF )
            {
               Err(3);
               free(buffer);
               status = 1;
            }
         }
      }
      free(buffer);
   }

   if( infile != stdin )      fclose(infile);
   if( outfile != stdout )    fclose(outfile);

   if( i != 0 && status == 0 )
   {
      if( remove(argv[1]) != 0 )
      {
         Err(4);
         status = 1;
      }
      if( rename(tmpname, argv[2]) != 0 )
      {
         Err(5);
         status = 1;
      }
   }
   return status;
}