textops.c

用来作为linux中SIP SERVER,完成VOIP网络电话中服务器的功能

		DBG(" %s: subst_f: replacing at offset %d [%.*s] with [%.*s]\n",
				exports.name, rpl->offset+off,
				rpl->size, rpl->offset+off+msg->buf,
				rpl->rpl.len, rpl->rpl.s);
		if ((l=del_lump(msg, rpl->offset+off, rpl->size, 0))==0)
			goto error;
		/* hack to avoid re-copying rpl, possible because both 
		 * replace_lst & lumps use pkg_malloc */
		if (insert_new_lump_after(l, rpl->rpl.s, rpl->rpl.len, 0)==0){
			LOG(L_ERR, "ERROR: %s: subst_f: could not insert new lump\n",
					exports.name);
			goto error;
		}
		/* hack continued: set rpl.s to 0 so that replace_lst_free will
		 * not free it */
		rpl->rpl.s=0;
		rpl->rpl.len=0;
	}
	ret=1;
error:
	DBG("subst_f: lst was %p\n", lst);
	if (lst) replace_lst_free(lst);
	if (nmatches<0)
		LOG(L_ERR, "ERROR: %s: subst_run failed\n", exports.name);
	return ret;
}



/* sed-perl style re: s/regular expression/replacement/flags, like
 *  subst but works on the message uri */
static int subst_uri_f(struct sip_msg* msg, char*  subst, char* ignored)
{
	char* tmp;
	int len;
	char c;
	struct subst_expr* se;
	str* result;
	
	se=(struct subst_expr*)subst;
	if (msg->new_uri.s){
		len=msg->new_uri.len;
		tmp=msg->new_uri.s;
	}else{
		tmp=msg->first_line.u.request.uri.s;
		len	=msg->first_line.u.request.uri.len;
	};
	/* ugly hack: 0 s[len], and restore it afterward
	 * (our re functions require 0 term strings), we can do this
	 * because we always alloc len+1 (new_uri) and for first_line, the
	 * message will always be > uri.len */
	c=tmp[len];
	tmp[len]=0;
	result=subst_str(tmp, msg, se, 0); /* pkg malloc'ed result */
	tmp[len]=c;
	if (result){
		DBG("%s: subst_uri_f: match - old uri= [%.*s], new uri= [%.*s]\n",
				exports.name, len, tmp,
				(result->len)?result->len:0,(result->s)?result->s:"");
		if (msg->new_uri.s) pkg_free(msg->new_uri.s);
		msg->new_uri=*result;
		msg->parsed_uri_ok=0; /* reset "use cached parsed uri" flag */
		pkg_free(result); /* free str* pointer */
		return 1; /* success */
	}
	return -1; /* false, no subst. made */
}
	


/* sed-perl style re: s/regular expression/replacement/flags, like
 *  subst but works on the user part of the uri */
static int subst_user_f(struct sip_msg* msg, char*  subst, char* ignored)
{
	int rval;
	str* result;
	struct subst_expr* se;
	struct action act;
	str user;
	char c;
	int nmatches;

	c=0;
	if (parse_sip_msg_uri(msg)<0){
		return -1; /* error, bad uri */
	}
	if (msg->parsed_uri.user.s==0){
		/* no user in uri */
		user.s="";
		user.len=0;
	}else{
		user=msg->parsed_uri.user;
		c=user.s[user.len];
		user.s[user.len]=0;
	}
	se=(struct subst_expr*)subst;
	result=subst_str(user.s, msg, se, &nmatches);/* pkg malloc'ed result */
	if (c)	user.s[user.len]=c;
	if (result == NULL) {
		if (nmatches<0)
			LOG(L_ERR, "subst_user(): subst_str() failed\n");
		return -1;
	}
	/* result->s[result->len] = '\0';  --subst_str returns 0-term strings */
	memset(&act, 0, sizeof(act)); /* be on the safe side */
	act.type = SET_USER_T;
	act.p1_type = STRING_ST;
	act.p1.string = result->s;
	rval = do_action(&act, msg);
	pkg_free(result);
	return rval;
}



static int remove_hf_f(struct sip_msg* msg, char* str_hf, char* foo)
{
	struct hdr_field *hf;
	struct lump* l;
	int cnt;

	cnt=0;
	/* we need to be sure we have seen all HFs */
	parse_headers(msg, HDR_EOH, 0);
	for (hf=msg->headers; hf; hf=hf->next) {
		if (hf->name.len!=((str *)str_hf)->len)
			continue;
		if (strncasecmp(hf->name.s, ((str *)str_hf)->s, hf->name.len)!=0)
			continue;
		l=del_lump(msg, hf->name.s-msg->buf, hf->len, 0);
		if (l==0) {
			LOG(L_ERR, "ERROR: remove_hf_f: no memory\n");
			return -1;
		}
		cnt++;
	}
	return cnt==0 ? -1 : 1;
}

static int is_present_hf_f(struct sip_msg* msg, char* str_hf, char* foo)
{
	struct hdr_field *hf;

	/* we need to be sure we have seen all HFs */
	parse_headers(msg, HDR_EOH, 0);
	for (hf=msg->headers; hf; hf=hf->next) {
		if (hf->name.len!=((str *)str_hf)->len)
			continue;
		if (strncasecmp(hf->name.s, ((str *)str_hf)->s, hf->name.len)!=0)
			continue;
		return 1;
	}
	return -1;
}



static int fixup_regex(void** param, int param_no)
{
	regex_t* re;

	DBG("module - fixing %s\n", (char*)(*param));
	if (param_no!=1) return 0;
	if ((re=pkg_malloc(sizeof(regex_t)))==0) return E_OUT_OF_MEM;
	if (regcomp(re, *param, REG_EXTENDED|REG_ICASE|REG_NEWLINE) ){
		pkg_free(re);
		LOG(L_ERR, "ERROR: %s : bad re %s\n", exports.name, (char*)*param);
		return E_BAD_RE;
	}
	/* free string */
	pkg_free(*param);
	/* replace it with the compiled re */
	*param=re;
	return 0;
}



static int fixup_substre(void** param, int param_no)
{
	struct subst_expr* se;
	str subst;

	DBG("%s module -- fixing %s\n", exports.name, (char*)(*param));
	if (param_no!=1) return 0;
	subst.s=*param;
	subst.len=strlen(*param);
	se=subst_parser(&subst);
	if (se==0){
		LOG(L_ERR, "ERROR: %s: bad subst. re %s\n", exports.name, 
				(char*)*param);
		return E_BAD_RE;
	}
	/* free string */
	pkg_free(*param);
	/* replace it with the compiled subst. re */
	*param=se;
	return 0;
}


static int append_time_f(struct sip_msg* msg, char* p1, char *p2)
{


	size_t len;
	char time_str[MAX_TIME];
	time_t now;
	struct tm *bd_time;

	now=time(0);

	bd_time=gmtime(&now);
	if (bd_time==NULL) {
		LOG(L_ERR, "ERROR: append_time: gmtime failed\n");
		return -1;
	}

	len=strftime(time_str, MAX_TIME, TIME_FORMAT, bd_time);
	if (len>MAX_TIME-2 || len==0) {
		LOG(L_ERR, "ERROR: append_time: unexpected time length\n");
		return -1;
	}

	time_str[len]='\r';
	time_str[len+1]='\n';


	if (add_lump_rpl(msg, time_str, len+2, LUMP_RPL_HDR)==0)
	{
		LOG(L_ERR, "ERROR: append_time: unable to add lump\n");
		return -1;
	}

	return 1;
}

static int append_to_reply_f(struct sip_msg* msg, char* key, char* str)
{
	if ( add_lump_rpl( msg, key, strlen(key), LUMP_RPL_HDR)==0 )
	{
		LOG(L_ERR,"ERROR:append_to_reply : unable to add lump_rl\n");
		return -1;
	}

	return 1;
}


/* add str1 to end of header or str1.r-uri.str2 */

static int append_hf_helper(struct sip_msg* msg, str *str1, str *str2)
{
	struct lump* anchor;
	char *s;
	int len;

	if (parse_headers(msg, HDR_EOH, 0) == -1) {
		LOG(L_ERR, "append_hf(): Error while parsing message\n");
		return -1;
	}

	anchor = anchor_lump(msg, msg->unparsed - msg->buf, 0, 0);
	if (anchor == 0) {
		LOG(L_ERR, "append_hf(): Can't get anchor\n");
		return -1;
	}

	len=str1->len;
	if (str2) len+= str2->len + REQ_LINE(msg).uri.len;

	s = (char*)pkg_malloc(len);
	if (!s) {
		LOG(L_ERR, "append_hf(): No memory left\n");
		return -1;
	}

	memcpy(s, str1->s, str1->len);
	if (str2) {
		memcpy(s+str1->len, REQ_LINE(msg).uri.s, REQ_LINE(msg).uri.len);
		memcpy(s+str1->len+REQ_LINE(msg).uri.len, str2->s, str2->len );
	}

	if (insert_new_lump_before(anchor, s, len, 0) == 0) {
		LOG(L_ERR, "append_hf(): Can't insert lump\n");
		pkg_free(s);
		return -1;
	}
	return 1;
}

static int append_hf(struct sip_msg *msg, char *str1, char *str2 )
{
	return append_hf_helper(msg, (str *) str1, (str *) 0);
}

static int append_urihf(struct sip_msg *msg, char *str1, char *str2 )
{
	return append_hf_helper(msg, (str *) str1, (str *) str2);
}



/*
 * Convert char* parameter to str* parameter
 */
static int str_fixup(void** param, int param_no)
{
	str* s;

	s = (str*)pkg_malloc(sizeof(str));
	if (!s) {
		LOG(L_ERR, "str_fixup(): No memory left\n");
		return E_UNSPEC;
	}

	s->s = (char*)*param;
	s->len = strlen(s->s);
	*param = (void*)s;

	return 0;
}