Function subst_run

re.c:509–583

! \brief run substitutions * \return 0 if no match or error, or subst result; if count!=0 * it will be set to 0 (no match), the number of matches * or -1 (error). * \note WARNING: input must be 0 terminated! */

 * \note WARNING: input must be 0 terminated!
 */
struct replace_lst* subst_run(struct subst_expr* se, const char* input,
								struct sip_msg* msg, int* count)
{
	struct replace_lst *head;
	struct replace_lst **crt;
	const char *p;
	int r;
	regmatch_t* pmatch;
	int nmatch;
	int eflags;
	int cnt;


	/* init */
	head=0;
	cnt=0;
	crt=&head;
	p=input;
	nmatch=se->max_pmatch+1;
	/* no of () referenced + 1 for the whole string: pmatch[0] */
	pmatch=pkg_malloc(nmatch*sizeof(regmatch_t));
	if (pmatch==0){
		LM_ERR("out of pkg mem. (pmatch)\n");
		goto error;
	}
	eflags=0;
	do{
		r=regexec(se->re, p, nmatch, pmatch, eflags);
		LM_DBG("running. r=%d\n", r);
		/* subst */
		if (r==0){ /* != REG_NOMATCH */
			/* some checks */
			if (pmatch[0].rm_so==-1){
				LM_ERR("unknown offset?\n");
				goto error;
			}
			if (pmatch[0].rm_so==pmatch[0].rm_eo){
				LM_ERR("matched string is empty... invalid regexp?\n");
				goto error;
			}
			*crt=pkg_malloc(sizeof(struct replace_lst));
			if (*crt==0){
				LM_ERR("out of pkg mem (crt)\n");
				goto error;
			}
			memset(*crt, 0, sizeof(struct replace_lst));
			(*crt)->offset=pmatch[0].rm_so+(int)(p-input);
			(*crt)->size=pmatch[0].rm_eo-pmatch[0].rm_so;
			LM_DBG("matched (%d, %d): [%.*s]\n",
					(*crt)->offset, (*crt)->size,
					(*crt)->size, input+(*crt)->offset);
			/* create subst. string */
			/* construct the string from replace[] */
			if (replace_build(p, nmatch, pmatch, se, msg, &((*crt)->rpl))<0){
				goto error;
			}
			crt=&((*crt)->next);
			p+=pmatch[0].rm_eo;