C++ skip_white函数代码示例

char *skip_token(char *ptr)
{
  ptr = skip_white(ptr);
  ptr = skip_not_white(ptr);
  ptr = skip_white(ptr);
  return (ptr);
}

static void parse_comment( char* in, M3u_Playlist::info_t& info, bool first )
{
	in = skip_white( in + 1 );
	const char* field = in;
	while ( *in && *in != ':' )
		in++;
	
	if ( *in == ':' )
	{
		const char* text = skip_white( in + 1 );
		if ( *text )
		{
			*in = 0;
			     if ( !strcmp( "Composer", field ) ) info.composer = text;
			else if ( !strcmp( "Engineer", field ) ) info.engineer = text;
			else if ( !strcmp( "Ripping" , field ) ) info.ripping  = text;
			else if ( !strcmp( "Tagging" , field ) ) info.tagging  = text;
			else
				text = 0;
			if ( text )
				return;
			*in = ':';
		}
	}
	
	if ( first )
		info.title = field;
}

static void
read_lisp_symbol (FILE *infile, char *buffer)
{
  char c;
  char *fillp = buffer;

  skip_white (infile);
  while (1)
    {
      c = getc (infile);
      if (c == '\\')
	*(++fillp) = getc (infile);
      else if (c == ' ' || c == '\t' || c == '\n' || c == '\r' || c == '(' || c == ')')
	{
	  ungetc (c, infile);
	  *fillp = 0;
	  break;
	}
      else
	*fillp++ = c;
    }

  if (! buffer[0])
    fprintf (stderr, "## expected a symbol, got '%c'\n", c);

  skip_white (infile);
}

static int parse_mask(lbind_Enum *et, const char *s, int *penum, lua_State *L) {
  *penum = 0;
  while (*s != '\0') {
    const char *e;
    int inversion = 0;
    lbind_EnumItem *item;
    s = skip_white(s);
    if (*s == '~') {
      inversion = 1;
      s = skip_white(s+1);
    }
    if (*s == '\0') break;
    e = skip_ident(s);
    if (e == s || (item = lbind_findenum(et, s, e-s)) == NULL) {
      if (L == NULL) return 0;
      if (e == s)
        return luaL_error(L, "unexpected token '%c' in %s", *s, et->name);
      else {
        lua_pushlstring(L, s, e-s);
        return luaL_error(L, "unexpected mask '%s' in %s", lua_tostring(L, -1), et->name);
      }
    }
    s = e;
    if (inversion)
      *penum &= ~item->value;
    else
      *penum |= item->value;
  }
  return 1;
}

pdf_obj *parse_pdf_array (char **start, char *end)
{
  pdf_obj *result, *tmp1;
#ifdef MEM_DEBUG
MEM_START
#endif
  skip_white(start, end);
  if (*((*start)++) != '[')
    return NULL;
  result = pdf_new_array ();
  skip_white(start, end);
  while (*start < end &&
	 **start != ']') {
    if ((tmp1 = parse_pdf_object (start, end)) == NULL) {
      pdf_release_obj (result);
      return NULL;
    };
    pdf_add_array (result, tmp1);
    skip_white(start, end);
  }
  if (*start >= end) {
    pdf_release_obj (result);
    fprintf (stderr, "\nArray ended prematurely\n");
    return NULL;
  }
  (*start)++;
#ifdef MEM_DEBUG
MEM_END
#endif
  return result;
}

char *
jump_etc(char *op)
{	char *p = op;

	/* try to get the type separated from the name */

	p = skip_white(p);	/* initial white space */

	if (strncmp(p, "enum", strlen("enum")) == 0) /* special case: a two-part typename */
	{	p += strlen("enum")+1;
		p = skip_white(p);
	}
	p = skip_nonwhite(p);	/* type name */
	p = skip_white(p);	/* white space */
	while (*p == '*') p++;	/* decorations */
	p = skip_white(p);	/* white space */

	if (*p == '\0')
		fatal("c_state format (%s)", op);

	if (strchr(p, '[')
	&&  !strchr(p, '{'))
	{	non_fatal("array initialization error, c_state (%s)", p);
		return (char *) 0;
	}

	return p;
}

NODE*
parse_any(SCANNER *s, int mode) {
  NODE *x = NULL;
  int c;

  skip_white(s);
  if (s_eof(s)) return raise(s, "unexpected end of file");

  c = s_peek(s);

  if (c == '(') {
    s_getc(s);
    x = parse_paren(s, mode);
    if (x == NULL) return NULL;
    if (s_eof(s)) {
      return raise(s, "unexpected end of file");
    }
    skip_white(s);
    if (s_getc(s) != ')') {
      return invalid_token(s);
    }
  } else if (c == '\'')
    x = parse_quote(s);
  else if (c == '`')
    return parse_bquote(s);
  else if (c == '"')
    x = parse_string(s);
  else if (isalnum((int)c) || strchr(SYMBOL_CHARS, c))
    x = parse_primitive(s);
  else
    return invalid_token(s);

  return x;
}

// Get next token.
static parse_ptr get_token(parse_ptr src, token_info & token, const char * path, int & line)
{
  src = skip_white(src, path, line);
  switch (*src) {
    case '{': case '}': case ',':
      // Simple token
      token.type = *src; token.line = line;
      ++src;
      break;

    case '"':
      // String constant
      token.type = '"'; token.line = line;
      token.value = "";
      do {
        for (++src; *src != '"'; ++src) {
          char c = *src;
          if (!c || c == '\n' || (c == '\\' && !src[1])) {
            pout("%s(%d): Missing terminating '\"'\n", path, line);
            token.type = '?'; token.line = line;
            return src;
          }
          if (c == '\\') {
            c = *++src;
            switch (c) {
              case 'n' : c = '\n'; break;
              case '\n': ++line; break;
              case '\\': case '"': break;
              default:
                pout("%s(%d): Unknown escape sequence '\\%c'\n", path, line, c);
                token.type = '?'; token.line = line;
                continue;
            }
          }
          token.value += c;
        }
        // Lookahead to detect string constant concatentation
        src = skip_white(++src, path, line);
      } while (*src == '"');
      break;

    case 0:
      // EOF
      token.type = 0; token.line = line;
      break;

    default:
      pout("%s(%d): Syntax error, invalid char '%c'\n", path, line, *src);
      token.type = '?'; token.line = line;
      while (*src && *src != '\n')
        ++src;
      break;
  }

  return src;
}

// Parse next letter/number pair.
// Returns the remaining line or NULL if end reached.
static const char *gcodep_parse_pair_with_linenumber(int line_num,
                                                     const char *line,
                                                     char *letter, float *value,
                                                     FILE *err_stream) {
  // TODO: error callback when we have errors with messages.
  if (line == NULL)
    return NULL;
  line = skip_white(line);

  if (*line == '\0' || *line == ';' || *line == '%')
    return NULL;

  if (*line == '(') {  // Comment between words; e.g. G0(move) X1(this axis)
    while (*line && *line != ')')
      line++;
    line = skip_white(line + 1);
    if (*line == '\0') return NULL;
  }

  *letter = toupper(*line++);
  if (*line == '\0') {
    fprintf(err_stream ? err_stream : stderr,
	    "// Line %d G-Code Syntax Error: expected value after '%c'\n",
            line_num, *letter);
    return NULL;
  }
  // If this line has a checksum, we ignore it. In fact, the line is done.
  if (*letter == '*')
    return NULL;
  while (*line && isspace(*line))
    line++;

  // Parsing with strtof() can be problematic if the line does
  // not contain spaces, and strof() sees the sequence 0X... as it treats that
  // as hex value. E.g. G0X1. Unlikely, but let's do a nasty workaround:
  char *repair_x = (*(line+1) == 'x' || *(line+1) == 'X') ? (char*)line+1 : NULL;
  if (repair_x) *repair_x = '\0';  // pretend that is the end of number.

  char *endptr;
  *value = strtof(line, &endptr);

  if (repair_x) *repair_x = 'X';  // Put the 'X' back.

  if (line == endptr) {
    fprintf(err_stream ? err_stream : stderr, "// Line %d G-Code Syntax Error:"
	    " Letter '%c' is not followed by a number `%s`.\n",
            line_num, *letter, line);
    return NULL;
  }
  line = endptr;

  line = skip_white(line); // Makes the line better to deal with.
  return line;  // We parsed something; return whatever is remaining.
}

char *
has_ident(const char *name,
	  char *first,
	  char *last)
{
    char *base;
    char *s, *t, *d, c;

    name = leaf_of(name);

    s = first;
    while ((t = base = strchr(s, '$')) != 0 && (t < last)) {
	t++;
	if ((s = exact(skip_camel(t), "Id")) != 0
	    || (s = exact(t, "Header")) != 0) {
	    if (*s == '$') {
		return base;
	    } else if ((*s == ':')
		       && is_inline(t, '$')) {
		/* RCS identifier can have pathname prepended */
		s = skip_white(s + 1);
		d = skip_text(s);
		c = *d;
		*d = EOS;
		while (is_inline(s, '/'))
		    s++;
		*d = c;
		if ((s = same_name(s, name)) != 0
		    && (s = exact(s, ",v")) != 0
		    && isspace(*s))
		    return base;
	    }
	}
	s = t;
    }

    s = first;
    while ((t = base = strchr(s, '@')) != 0 && (t < last)) {
	t++;
	if ((s = exact(t, "(#)")) != NULL) {
	    t = s;
	    /* some versions of SCCS don't do module-name */
	    if ((s = same_name(t, name)) != NULL)
		return base;

	    t = skip_text(t);	/* module-name, if any */
	    t = skip_white(t);
	    if ((s = same_name(t, name)) != NULL)
		return base;
	}
	s = t;
    }
    return 0;
}

NODE*
parse_paren(SCANNER *s, int mode) {
  NODE *head, *node, *x;

  skip_white(s);
  if (s_eof(s)) return raise(s, "unexpected end of file");

  head = node = new_node();
  node->t = NODE_CELL;
  while (!s_eof(s) && s_peek(s) != ')') {
    NODE *child;
    char q = s_peek(s) == ',';
    if (q) s_getc(s);

    child = parse_any(s, PARSE_ANY);
    if (child == NULL) return NULL;

    if ((mode & PARSE_BQUOTE) != 0 && !q) {
      NODE *r = new_node();
      r->t = NODE_QUOTE;
      r->car = child;
      child = r;
    }

    if (child->t == NODE_IDENT && !strcmp(".", child->s)) {
      if (!head->car) {
        free_node(child);
        return raise(s, "illegal dot operation");
      }
      free_node(child);

      child = parse_any(s, PARSE_ANY);
      if (child == NULL) return NULL;
      node->cdr = child;
      break;
    } else {
      if (head->car) {
        x = new_node();
        x->t = NODE_CELL;
        node->cdr = x;
        node = x;
      }
      node->car = child;
    }

    skip_white(s);
  }

  if (!head->car && !head->cdr)
    head->t = NODE_NIL;

  return head;
}

void
proc_parse_config(const char *token, char *cptr)
{
    char            tmpname[STRMAX];
    struct myproc **procp = &procwatch;

    /*
     * don't allow two entries with the same name 
     */
    copy_nword(cptr, tmpname, sizeof(tmpname));
    if (get_proc_by_name(tmpname) != NULL) {
        config_perror("Already have an entry for this process.");
        return;
    }

    /*
     * skip past used ones 
     */
    while (*procp != NULL)
        procp = &((*procp)->next);

    (*procp) = (struct myproc *) calloc(1, sizeof(struct myproc));
    if (*procp == NULL)
        return;                 /* memory alloc error */
    numprocs++;
    /*
     * not blank and not a comment 
     */
    copy_nword(cptr, (*procp)->name, sizeof((*procp)->name));
    cptr = skip_not_white(cptr);
    if ((cptr = skip_white(cptr))) {
        (*procp)->max = atoi(cptr);
        cptr = skip_not_white(cptr);
        if ((cptr = skip_white(cptr)))
            (*procp)->min = atoi(cptr);
        else
            (*procp)->min = 0;
    } else {
        /* Default to asssume that we require at least one
         *  such process to be running, but no upper limit */
        (*procp)->max = 0;
        (*procp)->min = 1;
        /* This frees "proc <procname> 0 0" to monitor
         * processes that should _not_ be running. */
    }
#ifdef NETSNMP_PROCFIXCMD
    sprintf((*procp)->fixcmd, NETSNMP_PROCFIXCMD, (*procp)->name);
#endif
    DEBUGMSGTL(("ucd-snmp/proc", "Read:  %s (%d) (%d)\n",
                (*procp)->name, (*procp)->max, (*procp)->min));
}

static void parse_fmtargs(parse_info *info, int *wide, int *count) {
    skip_white(info->fmt);
    parse_optint(&info->fmt, wide);
    skip_white(info->fmt);
    if (*info->fmt == '*') {
        ++info->fmt;
        skip_white(info->fmt);
        parse_optint(&info->fmt, count);
    }
    else if (*info->fmt == '$') {
        ++info->fmt;
        *count = -1;
    }
    skip_white(info->fmt);
}

static int parse_html_tag (char **start, char *end)
{
  int result = -1;
  char *token = NULL;
  int closing = 0;
  skip_white(start, end);
  if (*start < end) {
    if (**start == '/') {
      (*start)++;
      closing = 1;
    }
    if (*start < end && (token = parse_ident (start, end))) {
      downcase (token);
      {
	int i;
	for (i=0; i<sizeof(tags)/sizeof(tags[0]); i++) {
	  if (!strcmp (token, tags[i])) {
	    result = i;
	    if (closing) 
	      result += sizeof(tags)/sizeof(tags[0]);
	  }
	  break;
	}
	if (i>=sizeof(tags)/sizeof(tags[0]))
	  result = -1;
      }
      RELEASE (token);
    }
  }
  return result;
}

/**
 * @internal
 * parse mode: save everything
 */
void
_pm_save_everything(FILE *f, netsnmp_container *cin, int flags)
{
    char               line[STRINGMAX], *ptr;
    size_t             len;

    netsnmp_assert(NULL != f);
    netsnmp_assert(NULL != cin);

    while (fgets(line, sizeof(line), f) != NULL) {

        ptr = line;
        len = strlen(line) - 1;
        if (line[len] == '\n')
            line[len] = 0;

        /*
         * save blank line or comment?
         */
        if (flags & PM_FLAG_SKIP_WHITESPACE) {
            if (NULL == (ptr = skip_white(ptr)))
                continue;
        }

        ptr = strdup(line);
        if (NULL == ptr) {
            snmp_log(LOG_ERR,"malloc failed\n");
            break;
        }

        CONTAINER_INSERT(cin,ptr);
    }
}