port/merge Eurecom APER support from OPENAIRMME
Eurecom has developed APER support for asn1c as part of the OPENAIRMME
softare (a LTE MME). This is too important to let it bit-rout out
of asn1c. Let's forward-port and merge it.
diff --git a/skeletons/per_decoder.c b/skeletons/per_decoder.c
index 220d7f9..20fe1a1 100644
--- a/skeletons/per_decoder.c
+++ b/skeletons/per_decoder.c
@@ -37,6 +37,35 @@
}
asn_dec_rval_t
+aper_decode_complete(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td, void **sptr, const void *buffer, size_t size) {
+ asn_dec_rval_t rval;
+
+ rval = aper_decode(opt_codec_ctx, td, sptr, buffer, size, 0, 0);
+ if(rval.consumed) {
+ /*
+ * We've always given 8-aligned data,
+ * so convert bits to integral bytes.
+ */
+ rval.consumed += 7;
+ rval.consumed >>= 3;
+ } else if(rval.code == RC_OK) {
+ if(size) {
+ if(((uint8_t *)buffer)[0] == 0) {
+ rval.consumed = 1; /* 1 byte */
+ } else {
+ ASN_DEBUG("Expecting single zeroed byte");
+ rval.code = RC_FAIL;
+ }
+ } else {
+ /* Must contain at least 8 bits. */
+ rval.code = RC_WMORE;
+ }
+ }
+
+ return rval;
+}
+
+asn_dec_rval_t
uper_decode(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td, void **sptr, const void *buffer, size_t size, int skip_bits, int unused_bits) {
asn_codec_ctx_t s_codec_ctx;
asn_dec_rval_t rval;
@@ -91,3 +120,57 @@
return rval;
}
+asn_dec_rval_t
+aper_decode(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td, void **sptr, const void *buffer, size_t size, int skip_bits, int unused_bits) {
+ asn_codec_ctx_t s_codec_ctx;
+ asn_dec_rval_t rval;
+ asn_per_data_t pd;
+
+ if(skip_bits < 0 || skip_bits > 7
+ || unused_bits < 0 || unused_bits > 7
+ || (unused_bits > 0 && !size))
+ _ASN_DECODE_FAILED;
+
+ /*
+ * Stack checker requires that the codec context
+ * must be allocated on the stack.
+ */
+ if(opt_codec_ctx) {
+ if(opt_codec_ctx->max_stack_size) {
+ s_codec_ctx = *opt_codec_ctx;
+ opt_codec_ctx = &s_codec_ctx;
+ }
+ } else {
+ /* If context is not given, be security-conscious anyway */
+ memset(&s_codec_ctx, 0, sizeof(s_codec_ctx));
+ s_codec_ctx.max_stack_size = _ASN_DEFAULT_STACK_MAX;
+ opt_codec_ctx = &s_codec_ctx;
+ }
+
+ /* Fill in the position indicator */
+ memset(&pd, 0, sizeof(pd));
+ pd.buffer = (const uint8_t *)buffer;
+ pd.nboff = skip_bits;
+ pd.nbits = 8 * size - unused_bits; /* 8 is CHAR_BIT from <limits.h> */
+ if(pd.nboff > pd.nbits)
+ _ASN_DECODE_FAILED;
+
+ /*
+ * Invoke type-specific decoder.
+ */
+ if(!td->aper_decoder)
+ _ASN_DECODE_FAILED; /* PER is not compiled in */
+ rval = td->aper_decoder(opt_codec_ctx, td, 0, sptr, &pd);
+ if(rval.code == RC_OK) {
+ /* Return the number of consumed bits */
+ rval.consumed = ((pd.buffer - (const uint8_t *)buffer) << 3)
+ + pd.nboff - skip_bits;
+ ASN_DEBUG("PER decoding consumed %d, counted %d",
+ rval.consumed, pd.moved);
+ assert(rval.consumed == pd.moved);
+ } else {
+ /* PER codec is not a restartable */
+ rval.consumed = 0;
+ }
+ return rval;
+}