chew.c

早期freebsd实现

	    idx+=2;
	}
	else 
	{
	    catchar(&out, at(tos, idx));
	    idx++;
	}
    }
    delete_string(tos);
    *tos = out;
    pc++;
    
}
/* A command is all upper case,and alone on a line */
static int 
DEFUN( iscommand,(ptr, idx),
      string_type *ptr AND
      unsigned int idx)
{
    unsigned int len = 0;
    while (at(ptr,idx)) {
	    if (isupper(at(ptr,idx)) || at(ptr,idx) == ' ' ||
		at(ptr,idx) == '_') 
	    {
	     len++;
	     idx++;
	 }
	    else if(at(ptr,idx) == '\n')
	    {
		if (len >4) return 1;
		return 0;
	    }
	    else return 0;
	}
    return 0;

}


DEFUN(copy_past_newline,(ptr, idx, dst),
      string_type *ptr AND
      unsigned int idx AND
      string_type *dst)
{
    while (at(ptr, idx) && at(ptr, idx) != '\n') 
    {
	catchar(dst, at(ptr, idx));
	idx++;
	
    }    
    catchar(dst, at(ptr, idx));
    idx++;
    return idx;

}

WORD(icopy_past_newline)
{
    tos++;
    init_string(tos);
    idx = copy_past_newline(ptr, idx, tos);
    pc++;	
}

/* indent
   Take the string at the top of the stack, do some prettying */




WORD(kill_bogus_lines)
{
    int sl ;
    
    int nl = 0;
    int idx = 0;
    int c;
    int dot = 0    ;
    
    string_type out;    
    init_string(&out);
    /* Drop leading nl */
    while (at(tos,idx) == '\n')
    {
	idx++;
    }
    c = idx;
    
    /* Find the last char */
    while (at(tos,idx))
    {
	idx++;
    }
    
    /* find the last non white before the nl */
    idx--;
    
    while (idx && isspace(at(tos,idx)))
     idx--;
    idx++;
    
    /* Copy buffer upto last char, but blank lines before and after
       dots don't count */
    sl = 1;

    while (c < idx)
    {
	if (at(tos,c) == '\n' 
	    && at(tos,c+1) == '\n'
	    && at(tos,c+2) == '.') 
	{
	    /* Ignore two newlines before a dot*/
	    c++;
	}
	else if (at(tos,c) == '.' && sl)
	{
	    /* remember that this line started with a dot */
	    dot=2;
	}
	else if (at(tos,c) == '\n' 
		 && at(tos,c+1) == '\n'
		 && dot)
	{
	    c++;
	    /* Ignore two newlines when last line was dot */
	}

	catchar(&out, at(tos,c));
	if (at(tos,c) == '\n')
	{
	    sl = 1;
	    
	    if (dot == 2)dot=1;else dot = 0;
	}
	
	c++;	

    }
    
    /* Append nl*/
    catchar(&out, '\n');
    pc++;
    delete_string(tos);
    *tos = out;
    
    
}

WORD(indent)
{
    string_type out;
    int tab = 0;
    int idx = 0;
    int ol =0;
    init_string(&out);
    while (at(tos,idx)) {
	    switch (at(tos,idx)) 
	    {
	      case '\n':
		cattext(&out,"\n");
		idx++;
		if (tab) 
		{
		    cattext(&out,"    ");
		}
		ol = 0;
		break;
	      case '(':
		tab++;
		if (ol == 0)
		    cattext(&out,"   ");
		idx++;
		cattext(&out,"(");
		ol = 1;
		break;
	      case ')':
		tab--;
		cattext(&out,")");
		idx++;
		ol=1;
		
		break;
	      default:
		catchar(&out,at(tos,idx));
		ol=1;
		
		idx++;
		break;
	    }
	}	

    pc++;
    delete_string(tos);
    *tos = out;

}


WORD(get_stuff_in_command)
{
    tos++;
    init_string(tos);

    while (at(ptr, idx)) {
	    if (iscommand(ptr, idx))  break;
	    idx =   copy_past_newline(ptr, idx, tos);
	}
pc++;    
}

WORD(swap)
{
    string_type t;
    
    t = tos[0];
    tos[0] = tos[-1];
    tos[-1] =t; 
    pc++;
    
}

WORD(other_dup)
{
    tos++;
    init_string(tos);
    catstr(tos, tos-1);
    pc++;
    
}



WORD(icatstr)
{
    catstr(tos-1, tos);
    delete_string(tos);
    tos--;
    pc++;
    
}

WORD(skip_past_newline)
{
    while (at(ptr,idx) 
	   && at(ptr,idx) != '\n')
     idx++;
    idx++;
    pc++;
}


WORD(internalmode)
{
    internal_mode = *(isp);
    isp--;
    pc++;
}

WORD(maybecatstr)
{
    if (internal_wanted == internal_mode) 
    {
	catstr(tos-1, tos);
    }
    delete_string(tos);
    tos--;
    pc++;
    
}

char *
DEFUN(nextword,(string, word),
      char *string AND
      char **word)
{
    char *word_start;
    int idx;
    char *dst;
    char *src;
    
    int length = 0;
    
    while (isspace(*string) || *string == '-') {
	    if (*string == '-') 
	    {
		while (*string && *string != '\n') 
		 string++;
		
	    }
	    else {
		    string++;
		}
	}
    if (!*string) return 0;
    
    word_start = string;    	
    if (*string == '"') 
    {
	string++;
	length++;
	
	while (*string != '"') 
	{
	    string++;
	    length++;
	}
    }
    else     
    {
	

	while (!isspace(*string)) 
	{
	    string++;
	    length++;
	
	}
    }
    
    *word = malloc(length + 1);

    dst = *word;
    src = word_start;


    for (idx= 0; idx < length; idx++) 
    {
    
	if (src[idx] == '\\' && src[idx+1] == 'n') 
	{
	    *dst++ = '\n';
	    idx++;
    
	}
	else *dst++ = src[idx];
    }
    *dst++ = 0;





    if(*string)    
     return string + 1;
    else 
     return 0;
    
}
dict_type *root;
dict_type *
DEFUN(lookup_word,(word),
      char *word)
{
  dict_type *ptr = root;
  while (ptr) {
      if (strcmp(ptr->word, word) == 0) return ptr;
      ptr = ptr->next;
	    
    }
  if (warning)
   fprintf(stderr,"Can't find %s\n",word);
  return 0;
    
    
}

static void DEFUN_VOID(perform)
{
  tos = stack;
    
  while (at(ptr, idx)) {
      /* It's worth looking through the command list */
      if (iscommand(ptr, idx))
      {
	unsigned int i;
	int found = 0;

	char *next;
	dict_type *word ;
		
	(void)		nextword(addr(ptr, idx), &next);


	word = lookup_word(next);


		

	if (word) 
	{
	  exec(word);
	}
	else
	{
	  if (warning)
	   fprintf(stderr,"warning, %s is not recognised\n",  next);
	  skip_past_newline();
	}
		
      }
      else skip_past_newline();

    }
}

dict_type *
DEFUN(newentry,(word),
      char *word)
{
    dict_type *new = (dict_type *)malloc(sizeof(dict_type));
    new->word = word;
    new->next = root;
    root = new;
    new->code = (stinst_type *)malloc(sizeof(stinst_type ));
    new->code_length = 1;
    new->code_end = 0;
    return new;
    
}


unsigned int
DEFUN(add_to_definition,(entry, word), 
      dict_type *entry AND
      stinst_type word)
{
    if (entry->code_end == entry->code_length) 
    {
	entry->code_length += 2;
	entry->code =
	 (stinst_type *) realloc((char *)(entry->code),
			       entry->code_length *sizeof(word_type));
    }
    entry->code[entry->code_end] = word;
    
return     entry->code_end++;  
}







void
DEFUN(add_intrinsic,(name, func),
      char *name AND
      void (*func)())
{
    dict_type *new = newentry(name);
    add_to_definition(new, func);
    add_to_definition(new, 0);
}

WORD(push_addr)
{
    

}

void
DEFUN(add_var,(name),
      char *name)
{
    dict_type *new = newentry(name);
    add_to_definition(new, push_number);
    add_to_definition(new, (stinst_type)(&(new->var)));
    add_to_definition(new,0);
    
}
      



void 
DEFUN(compile, (string), 
      char *string)

{
    int jstack[STACK];
    int *jptr = jstack;
    /* add words to the dictionary */
    char *word;
    string = nextword(string, &word);
    while (string && *string && word[0]) 
    {
	if (strcmp(word,"var")==0) 
	{
 string=nextword(string, &word);
	  
	  add_var(word);
 string=nextword(string, &word);
	}
else	
	    
	if (word[0] == ':')
	{
	    dict_type *ptr;
	    /* Compile a word and add to dictionary */
	    string = nextword(string, &word);
	    
	    ptr = newentry(word);
	    string = nextword(string, &word);
	    while (word[0] != ';' ) 
	    {
		 switch (word[0]) 
		 {
		    
		    
		   case '"':
		     /* got a string, embed magic push string
			function */
		     add_to_definition(ptr, push_text);
		     add_to_definition(ptr, (stinst_type)(word+1));
		     break;
		   case '0':
		   case '1':
		   case '2':
		   case '3':
		   case '4':
		   case '5':
		   case '6':
		   case '7':
		   case '8':
		   case '9':
		     /* Got a number, embedd the magic push number
			function */
		     add_to_definition(ptr, push_number);
		     add_to_definition(ptr, atol(word));
		     break;
		   default:
		     add_to_definition(ptr, call);
		     add_to_definition(ptr, lookup_word(word));
		 }

		string = nextword(string, &word);		     
	    }
	    add_to_definition(ptr,0);
	    string = nextword(string, &word);
	}
	else 
	{
	    fprintf(stderr,"syntax error at %s\n",string-1);
	}	    
    }

}

 
static void DEFUN_VOID(bang)
{
*(int *)((isp[0])) = isp[-1];
isp-=2;
pc++;

}

WORD(atsign)
{
    isp[0] = *(int *)(isp[0]);
    pc++;
}

WORD(hello)
{
    
    printf("hello\n");
    pc++;    
}



static void DEFUN(read_in, (str, file), 
	   string_type *str AND
		  FILE *file)
{
    char buff[10000];    
    unsigned int r;
    do 
    {
	r = fread(buff, 1, sizeof(buff), file);
	catbuf(str, buff, r);
    }
    while (r);
    buff[0] = 0;
    
    catbuf(str, buff,1);
    
}


static void DEFUN_VOID(usage)
{
    fprintf(stderr,"usage: -[d|i|g] <file >file\n");
    exit(33);    
}

int DEFUN(main,(ac,av),
int ac AND
char *av[])
{
  unsigned int i;
  string_type buffer;
  string_type pptr;

  init_string(&buffer);
  init_string(&pptr);
  init_string(stack+0);
  tos=stack+1;
  ptr = &pptr;
    
  add_intrinsic("push_text", push_text);
  add_intrinsic("!", bang);
  add_intrinsic("@", atsign);
  add_intrinsic("hello",hello);    
  add_intrinsic("skip_past_newline", skip_past_newline );
  add_intrinsic("catstr", icatstr );
  add_intrinsic("copy_past_newline", icopy_past_newline );
  add_intrinsic("dup", other_dup );
  add_intrinsic("remchar", remchar );
  add_intrinsic("get_stuff_in_command", get_stuff_in_command );
  add_intrinsic("do_fancy_stuff", do_fancy_stuff );
  add_intrinsic("bulletize", bulletize );
  add_intrinsic("courierize", courierize );
  /* If the following line gives an error, exit() is not declared in the
     ../hosts/foo.h file for this host.  Fix it there, not here!  */
  add_intrinsic("exit", exit );
  add_intrinsic("swap", swap );
  add_intrinsic("outputdots", outputdots );
  add_intrinsic("exfunstuff", exfunstuff );
  add_intrinsic("maybecatstr", maybecatstr );
  add_intrinsic("translatecomments", translatecomments );
  add_intrinsic("kill_bogus_lines", kill_bogus_lines);
  add_intrinsic("indent", indent);
  add_intrinsic("internalmode", internalmode);
    
  /* Put a nl at the start */
  catchar(&buffer,'\n');

  read_in(&buffer, stdin); 
  remove_noncomments(&buffer, ptr);
  for (i= 1; i < ac; i++) 
  {
    if (av[i][0] == '-')
    {
      if (av[i][1] == 'f')
      {
	string_type b;
	FILE *f;
	init_string(&b);

	f  = fopen(av[i+1],"r");
	if (!f) 
	{
	  fprintf(stderr,"Can't open the input file %s\n",av[i+1]);
	  return 33;
	}
		
		  
	read_in(&b, f);
	compile(b.ptr);
	perform();	
      }
      else if (av[i][1] == 'i') 
      {
	internal_wanted = 1;
      }
      else if (av[i][1] == 'w') 
      {
	warning = 1;
      }
    }

  }      
  write_buffer(stack+0);
  return 0;
}