lfname.c

网络爬虫程序

  lfname_lsp_var_free(var->param3);
  if(var->type == LF_LSP_STR)
    _free(var->val.str);
  _free(var);
}

static struct lfname_lsp_var *lfname_lsp_analyze(const char **pstr)
{
  struct lfname_lsp_var *retv = NULL;
  enum lfname_lsp_type type;
  char *p;
  const char *cp;

  type = lfname_lsp_token_type(pstr);

  switch (type)
  {
  case LF_LSP_UNKNOWN:
    xprintf(0, gettext("LSP analyze error: bad token at - %s\n"), *pstr);
    break;
  case LF_LSP_NUM:
    {
      int nval;

      errno = 0;
      nval = strtol(*pstr, &p, 0);

      if((errno == ERANGE) || (*p != '\0' && *p != ')' && *p != ' '))
      {
        xprintf(0, gettext("LSP analyze error: bad numeric value at - %s\n"),
          *pstr);
        break;
      }
      retv = lfname_lsp_var_new(type);
      retv->val.num = nval;
      *pstr = p;
    }
    break;
  case LF_LSP_MACRO:
    {
      if(!lfname_check_macro(**pstr) ||
        (*(*pstr + 1) != '\0' && *(*pstr + 1) != ')' && *(*pstr + 1) != ' '))
      {
        xprintf(0, gettext("LSP analyze error: bad macro at - %s\n"),
          *pstr - 1);
        break;
      }
      retv = lfname_lsp_var_new(type);
      retv->val.macro = **pstr;
      *pstr += 1;
    }
    break;
  case LF_LSP_STR:
    {
      char *tmp = _malloc(strlen(*pstr) + 1);
      char *tp;

      cp = *pstr;
      tp = tmp;

      while(*cp)
      {
        if(*cp == '\"')
          break;
        if(*cp == '\\')
          cp++;
        *tp = *cp;
        tp++;
        if(*cp)
          cp++;
      }
      *tp = '\0';

      if(*cp != '\"')
      {
        xprintf(0,
          gettext("LSP analyze error: unterminated string at - %s\n"),
          *pstr - 1);
        break;
      }
      retv = lfname_lsp_var_new(type);
      retv->val.str = tl_strdup(tmp);
      _free(tmp);
      *pstr = cp + 1;
    }
    break;
  default:
    {
      struct lfname_lsp_var *p1 = NULL;
      struct lfname_lsp_var *p2 = NULL;
      struct lfname_lsp_var *p3 = NULL;
      if(lfname_lsp_ftbl[type].params >= 1)
      {
        cp = *pstr;
        p1 = lfname_lsp_analyze(pstr);
        if(!p1)
          break;
        if(p1->rettype != lfname_lsp_ftbl[type].p1type)
        {
          xprintf(0,
            gettext("LSP analyze error: bad parameter type at - %s\n"), cp);
          lfname_lsp_var_free(p1);
          break;
        }
      }
      if(p1 && lfname_lsp_ftbl[type].params >= 2)
      {
        cp = *pstr;
        p2 = lfname_lsp_analyze(pstr);
        if(!p2)
        {
          lfname_lsp_var_free(p1);
          break;
        }
        if(p2->rettype != lfname_lsp_ftbl[type].p2type)
        {
          xprintf(0,
            gettext("LSP analyze error: bad parameter type at - %s\n"), cp);
          lfname_lsp_var_free(p1);
          lfname_lsp_var_free(p2);
          break;
        }
      }
      if(p2 && lfname_lsp_ftbl[type].params >= 3)
      {
        cp = *pstr;
        p3 = lfname_lsp_analyze(pstr);
        if(!p3)
        {
          lfname_lsp_var_free(p1);
          lfname_lsp_var_free(p2);
          break;
        }
        if(p3->rettype != lfname_lsp_ftbl[type].p3type)
        {
          xprintf(0,
            gettext("LSP analyze error: bad parameter type at - %s\n"), cp);
          lfname_lsp_var_free(p1);
          lfname_lsp_var_free(p2);
          lfname_lsp_var_free(p3);
          break;
        }
      }
      while(**pstr == ' ')
        (*pstr)++;
      if(**pstr != ')')
      {
        xprintf(0, gettext("LSP analyze error: bad token at - %s\n"), *pstr);
        if(p1)
          lfname_lsp_var_free(p1);
        if(p2)
          lfname_lsp_var_free(p2);
        if(p3)
          lfname_lsp_var_free(p3);
      }
      else
      {
        (*pstr)++;
        retv = lfname_lsp_var_new(type);
        retv->param1 = p1;
        retv->param2 = p2;
        retv->param3 = p3;
      }
    }
    break;
  }

  return retv;
}

/*
Removes a parameter from an URL-String.
e.g. removeparameter("myurl.php3?var=something","var") will convert the
URL to "myurl.php3?"
*/
static char *lfname_fn_removeparameter(char *urlstr, char *var)
{
  char *p, *found;
  int pos1;
  int parlen;

  /* &var= */
  p = tl_str_concat(NULL, "&", var, "=", NULL);
  parlen = strlen(p);

  found = strstr(urlstr, p);
  if(!found)
  {
    /* ?var= */
    *p = '?';
    found = strstr(urlstr, p);
    if(!found)
    {
      /* var= */
      if((parlen > 1) && !strncmp(urlstr, p + 1, parlen - 1))
      {
        found = urlstr;
      }
    }
  }
  _free(p);

  if(!found)
    return tl_strdup(urlstr);

  pos1 = found - urlstr + 1;

  found = strstr((urlstr + pos1 + 1), "&");
  if(!found)
  {
    return tl_strndup(urlstr, pos1 - 1);
  }

  urlstr = tl_strndup(urlstr, pos1);

  return tl_str_concat(urlstr, found + 1, NULL);
}

/*
reads a value from parameter of an URL-String.
e.g. lfname_fn_getvalue("myurl.php3?var=value","var") results in value
*/
static char *lfname_fn_getvalue(char *urlstr, char *var)
{
  char *p, *found;
  int parlen;

  /* &var= */
  p = tl_str_concat(NULL, "&", var, "=", NULL);
  parlen = strlen(p);

  found = strstr(urlstr, p);
  if(!found)
  {
    /* ?var= */
    *p = '?';
    found = strstr(urlstr, p);
    if(!found)
    {
      /* var= */
      if((parlen > 1) && !strncmp(urlstr, p + 1, parlen - 1))
      {
        parlen--;
        found = urlstr;
      }
    }
  }
  _free(p);

  if(!found)
    return tl_strdup("");

  return tl_strndup(found + parlen, strcspn(found + parlen, "&"));
}

static int lfname_lsp_eval(struct lfname_lsp_interp *interp,
  struct lfname_lsp_var *var)
{
  if(var->param1)
    lfname_lsp_eval(interp, var->param1);
  if(var->param2)
    lfname_lsp_eval(interp, var->param2);
  if(var->param3)
    lfname_lsp_eval(interp, var->param3);

  var->ret_val.str = NULL;

  switch (var->type)
  {
  case LF_LSP_UNKNOWN:
    break;
  case LF_LSP_STR:
    var->ret_val.str = tl_strdup(var->val.str);
    break;
  case LF_LSP_NUM:
    var->ret_val.num = var->val.num;
    break;
  case LF_LSP_MACRO:
    var->ret_val.str =
      tl_strdup(lfname_interp_get_macro(interp, var->val.macro));
    break;
  case LF_LSP_SUB:
#ifdef HAVE_REGEX
    var->ret_val.str = lfname_re_sub(interp->orig,
      interp->urlstr, var->param1->ret_val.num);
#endif
    break;
  case LF_LSP_SC:
    {
      char *p;
      p =
        _malloc(strlen(var->param1->ret_val.str) +
        strlen(var->param2->ret_val.str) + 1);
      strcpy(p, var->param1->ret_val.str);
      strcat(p, var->param2->ret_val.str);
      var->ret_val.str = p;
    }
    break;
  case LF_LSP_SS:
    {
      char *p;
      p = var->param1->ret_val.str;
      if(var->param2->ret_val.num > 0)
        p +=
          (strlen(p) >=
          var->param2->ret_val.num) ? var->param2->ret_val.num : strlen(p);
      if(var->param3->ret_val.num > 0)
        var->ret_val.str = tl_strndup(p, var->param3->ret_val.num);
      else
        var->ret_val.str = tl_strdup(p);
    }
    break;
  case LF_LSP_HASH:
    var->ret_val.num = str_hash_func(var->param2->ret_val.num,
      (dllist_t) var->param1->ret_val.str);
    break;
  case LF_LSP_MD5:
    var->ret_val.str = _md5(var->param1->ret_val.str);
    break;
  case LF_LSP_LOWER:
    var->ret_val.str = lowerstr(var->param1->ret_val.str);
    break;
  case LF_LSP_UPPER:
    var->ret_val.str = upperstr(var->param1->ret_val.str);
    break;
  case LF_LSP_UENC:
    var->ret_val.str = url_encode_str(var->param1->ret_val.str,
      var->param2->ret_val.str);
    break;
  case LF_LSP_UDEC:
    var->ret_val.str = url_decode_str(var->param1->ret_val.str,
      strlen(var->param1->ret_val.str));
    break;
  case LF_LSP_DELCHR:
    var->ret_val.str = tr_del_chr(var->param2->ret_val.str,
      var->param1->ret_val.str);
    break;
  case LF_LSP_TRCHR:
    var->ret_val.str = tr_chr_chr(var->param2->ret_val.str,
      var->param3->ret_val.str, var->param1->ret_val.str);
    break;
  case LF_LSP_TRSTR:
    var->ret_val.str = tr_str_str(var->param2->ret_val.str,
      var->param3->ret_val.str, var->param1->ret_val.str);
    break;
  case LF_LSP_STRSPN:
    var->ret_val.num = strspn(var->param1->ret_val.str,
      var->param2->ret_val.str);
    break;
  case LF_LSP_STRCSPN:
    var->ret_val.num = strcspn(var->param1->ret_val.str,
      var->param2->ret_val.str);
    break;
  case LF_LSP_STRLEN:
    var->ret_val.num = strlen(var->param1->ret_val.str);
    break;
  case LF_LSP_NRSTR:
    {
      char pom[1024];
      snprintf(pom, sizeof(pom), var->param1->ret_val.str, var->param2->ret_val.num);
      var->ret_val.str = tl_strdup(pom);
    }
    break;
  case LF_LSP_LCHR:
    {
      char *p;
      p = strrchr(var->param1->ret_val.str, *var->param2->ret_val.str);
      var->ret_val.num = p ? p - var->param1->ret_val.str : 0;
    }
    break;
  case LF_LSP_PLS:
    var->ret_val.num = var->param1->ret_val.num + var->param2->ret_val.num;
    break;
  case LF_LSP_MNS:
    var->ret_val.num = var->param1->ret_val.num - var->param2->ret_val.num;
    break;
  case LF_LSP_MOD:
    var->ret_val.num = var->param1->ret_val.num % var->param2->ret_val.num;
    break;
  case LF_LSP_MUL:
    var->ret_val.num = var->param1->ret_val.num * var->param2->ret_val.num;
    break;
  case LF_LSP_DIV:
    var->ret_val.num = var->param1->ret_val.num / var->param2->ret_val.num;
    break;
  case LF_LSP_REMOVEPARAMETER:
    var->ret_val.str =
      lfname_fn_removeparameter(var->param1->ret_val.str,
      var->param2->ret_val.str);
    break;
  case LF_LSP_GETVALUE:
    var->ret_val.str =
      lfname_fn_getvalue(var->param1->ret_val.str, var->param2->ret_val.str);
    break;
  case LF_LSP_SIF:
    var->ret_val.str = var->param1->ret_val.num ?
      tl_strdup(var->param2->ret_val.str) :
      tl_strdup(var->param3->ret_val.str);
    break;
  case LF_LSP_NOT:
    var->ret_val.num = !var->param1->ret_val.num;
    break;
  case LF_LSP_AND:
    var->ret_val.num = var->param1->ret_val.num && var->param2->ret_val.num;
    break;
  case LF_LSP_OR:
    var->ret_val.num = var->param1->ret_val.num || var->param2->ret_val.num;
    break;
  case LF_LSP_GETEXT:
    var->ret_val.str = tl_strdup(tl_get_extension(var->param1->ret_val.str));
    break;
  case LF_LSP_SEQ:
    var->ret_val.num = !strcmp(var->param1->ret_val.str,
      var->param2->ret_val.str);
    break;
#ifdef HAVE_MOZJS
  case LF_LSP_JSF:
    var->ret_val.str = pjs_run_fnrules_func(var->param1->ret_val.str, interp);
    break;
#endif
  }
  if(var->rettype == LF_LSP_STR && !var->ret_val.str)
    var->ret_val.str = tl_strdup("");

  return 0;
}

static char *lfname_lsp_get_by_url(struct lfname_lsp_interp *interp)
{
  char *retv = NULL;
  struct lfname_lsp_var *variant;
  const char *p;
  p = interp->orig->transstr;

  variant = lfname_lsp_analyze(&p);

  if(variant)
  {
    lfname_lsp_eval(interp, variant);
    if(variant->rettype == LF_LSP_NUM)
    {
      char nr[10];
      sprintf(nr, "%d", variant->ret_val.num);
      retv = tl_strdup(nr);
    }
    else
    {
      retv = tl_strdup(variant->ret_val.str);
    }
    lfname_lsp_var_free(variant);
  }

  return retv;
}