libasn1c/src/constraints.c

94 lines
2.2 KiB
C

#include "asn_internal.h"
#include "constraints.h"
int
asn_generic_no_constraint(asn_TYPE_descriptor_t *type_descriptor,
const void *struct_ptr, asn_app_constraint_failed_f *cb, void *key) {
(void)type_descriptor; /* Unused argument */
(void)struct_ptr; /* Unused argument */
(void)cb; /* Unused argument */
(void)key; /* Unused argument */
/* Nothing to check */
return 0;
}
int
asn_generic_unknown_constraint(asn_TYPE_descriptor_t *type_descriptor,
const void *struct_ptr, asn_app_constraint_failed_f *cb, void *key) {
(void)type_descriptor; /* Unused argument */
(void)struct_ptr; /* Unused argument */
(void)cb; /* Unused argument */
(void)key; /* Unused argument */
/* Unknown how to check */
return 0;
}
struct errbufDesc {
asn_TYPE_descriptor_t *failed_type;
const void *failed_struct_ptr;
char *errbuf;
size_t errlen;
};
static void
_asn_i_ctfailcb(void *key, asn_TYPE_descriptor_t *td, const void *sptr, const char *fmt, ...) {
struct errbufDesc *arg = key;
va_list ap;
ssize_t vlen;
ssize_t maxlen;
arg->failed_type = td;
arg->failed_struct_ptr = sptr;
maxlen = arg->errlen;
if(maxlen <= 0)
return;
va_start(ap, fmt);
vlen = vsnprintf(arg->errbuf, maxlen, fmt, ap);
va_end(ap);
if(vlen >= maxlen) {
arg->errbuf[maxlen-1] = '\0'; /* Ensuring libc correctness */
arg->errlen = maxlen - 1; /* Not counting termination */
return;
} else if(vlen >= 0) {
arg->errbuf[vlen] = '\0'; /* Ensuring libc correctness */
arg->errlen = vlen; /* Not counting termination */
} else {
/*
* The libc on this system is broken.
*/
vlen = sizeof("<broken vsnprintf>") - 1;
maxlen--;
arg->errlen = vlen < maxlen ? vlen : maxlen;
memcpy(arg->errbuf, "<broken vsnprintf>", arg->errlen);
arg->errbuf[arg->errlen] = 0;
}
return;
}
int
asn_check_constraints(asn_TYPE_descriptor_t *type_descriptor,
const void *struct_ptr, char *errbuf, size_t *errlen) {
struct errbufDesc arg;
int ret;
arg.failed_type = 0;
arg.failed_struct_ptr = 0;
arg.errbuf = errbuf;
arg.errlen = errlen ? *errlen : 0;
ret = type_descriptor->check_constraints(type_descriptor,
struct_ptr, _asn_i_ctfailcb, &arg);
if(ret == -1 && errlen)
*errlen = arg.errlen;
return ret;
}