/* returns the substitution result in a str, input must be 0 term
* 0 on no match or malloc error */
str* subst_str(char *input, struct sip_msg* msg, struct subst_expr* se)
{
str* res;
struct replace_lst *lst;
struct replace_lst* l;
int len;
int size;
char* p;
char* dest;
char* end;
/* compute the len */
len=strlen(input);
end=input+len;
lst=subst_run(se, input, msg);
if (lst==0){
DBG("subst_str: no match\n");
return 0;
}
for (l=lst; l; l=l->next)
len+=(int)(l->rpl.len)-l->size;
res=pkg_malloc(sizeof(str));
if (res==0){
LOG(L_ERR, "ERROR: subst_str: mem. allocation error\n");
goto error;
}
res->s=pkg_malloc(len+1); /* space for null termination */
res->s[len]=0;
if (res->s==0){
LOG(L_ERR, "ERROR: subst_str: mem. allocation error (res->s)\n");
goto error;
}
res->len=len;
/* replace */
dest=res->s;
p=input;
for(l=lst; l; l=l->next){
size=l->offset+input-p;
memcpy(dest, p, size); /* copy till offset */
p+=size + l->size; /* skip l->size bytes */
dest+=size;
if (l->rpl.len){
memcpy(dest, l->rpl.s, l->rpl.len);
dest+=l->rpl.len;
}
}
memcpy(dest, p, end-p);
if(lst) replace_lst_free(lst);
return res;
error:
if (lst) replace_lst_free(lst);
if (res){
if (res->s) pkg_free(res->s);
pkg_free(res);
}
return 0;
}
/* sed-perl style re: s/regular expression/replacement/flags */
static int subst_body_f(struct sip_msg* msg, char* subst, char* ignored)
{
struct lump* l;
struct replace_lst* lst;
struct replace_lst* rpl;
char* begin;
struct subst_expr* se;
int off;
int ret;
int nmatches;
str body;
if ( get_body(msg,&body)!=0 || body.len==0) {
LM_DBG("message body has zero length\n");
return -1;
}
se=(struct subst_expr*)subst;
begin=body.s;
off=begin-msg->buf;
ret=-1;
if ((lst=subst_run(se, begin, msg, &nmatches))==0)
goto error; /* not found */
for (rpl=lst; rpl; rpl=rpl->next){
LM_DBG("%s 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){
LM_ERR("%s 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:
LM_DBG("lst was %p\n", lst);
if (lst) replace_lst_free(lst);
if (nmatches<0)
LM_ERR("%s subst_run failed\n", exports.name);
return ret;
}
/* sed-perl style re: s/regular expression/replacement/flags */
static int subst_f(struct sip_msg* msg, char* subst, char* ignored)
{
struct lump* l;
struct replace_lst* lst;
struct replace_lst* rpl;
char* begin;
struct subst_expr* se;
int off;
int ret;
int nmatches;
se=(struct subst_expr*)subst;
begin=get_header(msg); /* start after first line to avoid replacing
the uri */
off=begin-msg->buf;
ret=-1;
if ((lst=subst_run(se, begin, msg, &nmatches))==0)
goto error; /* not found */
for (rpl=lst; rpl; rpl=rpl->next){
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;
}
/* WARNING: input must be 0 terminated! */
struct replace_lst* subst_run(struct subst_expr* se, char* input,
struct sip_msg* msg)
{
struct replace_lst *head;
struct replace_lst **crt;
char *p;
int r;
regmatch_t* pmatch;
int nmatch;
int eflags;
/* init */
head=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){
LOG(L_ERR, "ERROR: subst_run_ out of mem. (pmatch)\n");
goto error;
}
eflags=0;
do{
r=regexec(se->re, p, nmatch, pmatch, eflags);
DBG("subst_run: running. r=%d\n", r);
/* subst */
if (r==0){ /* != REG_NOMATCH */
/* change eflags, not to match any more at string start */
eflags|=REG_NOTBOL;
*crt=pkg_malloc(sizeof(struct replace_lst));
if (*crt==0){
LOG(L_ERR, "ERROR: subst_run: out of mem (crt)\n");
goto error;
}
memset(*crt, 0, sizeof(struct replace_lst));
if (pmatch[0].rm_so==-1){
LOG(L_ERR, "ERROR: subst_run: unknown offset?\n");
goto error;
}
(*crt)->offset=pmatch[0].rm_so+(int)(p-input);
(*crt)->size=pmatch[0].rm_eo-pmatch[0].rm_so;
DBG("subst_run: 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;
}
}while((r==0) && se->replace_all);
pkg_free(pmatch);
return head;
error:
if (head) replace_lst_free(head);
if (pmatch) pkg_free(pmatch);
return 0;
}
/*! \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!
*/
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;
/* is it still a string start? */
if (*(p-1)=='\n' || *(p-1)=='\r')
eflags&=~REG_NOTBOL;
else
eflags|=REG_NOTBOL;
cnt++;
}
}while((r==0) && se->replace_all);
pkg_free(pmatch);
if (count)*count=cnt;
return head;
error:
if (head) replace_lst_free(head);
if (pmatch) pkg_free(pmatch);
if (count) *count=-1;
return 0;
}
