constr_choice.c

RSA加密/解密算法源码 asn1c-0.9.12

		const void *memb_ptr;

		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(const void * const *)
					((const char *)ptr + elm->memb_offset);
		} else {
			memb_ptr = (const void *)
					((const char *)ptr + elm->memb_offset);
		}

		return asn_TYPE_outmost_tag(elm->type, memb_ptr,
			elm->tag_mode, elm->tag);
	} else {
		return (ber_tlv_tag_t)-1;
	}
}

int
CHOICE_constraint(asn_TYPE_descriptor_t *td, const void *sptr,
		asn_app_consume_bytes_f *app_errlog, void *app_key) {
	asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
	int present;

	if(!sptr) {
		_ASN_ERRLOG(app_errlog, app_key,
			"%s: value not given (%s:%d)",
			td->name, __FILE__, __LINE__);
		return -1;
	}

	/*
	 * Figure out which CHOICE element is encoded.
	 */
	present = _fetch_present_idx(sptr, specs->pres_offset,specs->pres_size);
	if(present > 0 && present <= td->elements_count) {
		asn_TYPE_member_t *elm = &td->elements[present-1];
		const void *memb_ptr;

		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(const void * const *)((const char *)sptr + elm->memb_offset);
			if(!memb_ptr) {
				if(elm->optional)
					return 0;
				_ASN_ERRLOG(app_errlog, app_key,
					"%s: mandatory CHOICE element %s absent (%s:%d)",
					td->name, elm->name, __FILE__, __LINE__);
				return -1;
			}
		} else {
			memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
		}

		if(elm->memb_constraints) {
			return elm->memb_constraints(elm->type, memb_ptr,
				app_errlog, app_key);
		} else {
			int ret = elm->type->check_constraints(elm->type,
					memb_ptr, app_errlog, app_key);
			/*
			 * Cannot inherit it eralier:
			 * need to make sure we get the updated version.
			 */
			elm->memb_constraints = elm->type->check_constraints;
			return ret;
		}
	} else {
		_ASN_ERRLOG(app_errlog, app_key,
			"%s: no CHOICE element given (%s:%d)",
			td->name, __FILE__, __LINE__);
		return -1;
	}
}

#undef	XER_ADVANCE
#define	XER_ADVANCE(num_bytes)	do {			\
		size_t num = num_bytes;			\
		buf_ptr = ((char *)buf_ptr) + num;	\
		size -= num;				\
		consumed_myself += num;			\
	} while(0)

/*
 * Decode the XER (XML) data.
 */
asn_dec_rval_t
CHOICE_decode_xer(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
	void **struct_ptr, const char *opt_mname,
		void *buf_ptr, size_t size) {
	/*
	 * Bring closer parts of structure description.
	 */
	asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
	const char *xml_tag = opt_mname ? opt_mname : td->xml_tag;

	/*
	 * Parts of the structure being constructed.
	 */
	void *st = *struct_ptr;	/* Target structure. */
	asn_struct_ctx_t *ctx;	/* Decoder context */

	asn_dec_rval_t rval;		/* Return value of a decoder */
	ssize_t consumed_myself = 0;	/* Consumed bytes from ptr */
	int edx;			/* Element index */

	/*
	 * Create the target structure if it is not present already.
	 */
	if(st == 0) {
		st = *struct_ptr = CALLOC(1, specs->struct_size);
		if(st == 0) RETURN(RC_FAIL);
	}

	/*
	 * Restore parsing context.
	 */
	ctx = (asn_struct_ctx_t *)((char *)st + specs->ctx_offset);


	/*
	 * Phases of XER/XML processing:
	 * Phase 0: Check that the opening tag matches our expectations.
	 * Phase 1: Processing body and reacting on closing tag.
	 * Phase 2: Processing inner type.
	 * Phase 3: Only waiting for closing tag.
	 * Phase 4: Skipping unknown extensions.
	 * Phase 5: PHASED OUT
	 */
	for(edx = ctx->step; ctx->phase <= 4;) {
		pxer_chunk_type_e ch_type;	/* XER chunk type */
		ssize_t ch_size;		/* Chunk size */
		xer_check_tag_e tcv;		/* Tag check value */
		asn_TYPE_member_t *elm;

		/*
		 * Go inside the member.
		 */
		if(ctx->phase == 2) {
			asn_dec_rval_t tmprval;
			void *memb_ptr;		/* Pointer to the member */
			void **memb_ptr2;	/* Pointer to that pointer */

			elm = &td->elements[edx];

			if(elm->flags & ATF_POINTER) {
				/* Member is a pointer to another structure */
				memb_ptr2 = (void **)((char *)st
					+ elm->memb_offset);
			} else {
				memb_ptr = (char *)st + elm->memb_offset;
				memb_ptr2 = &memb_ptr;
			}

			/* Start/Continue decoding the inner member */
			tmprval = elm->type->xer_decoder(opt_codec_ctx,
					elm->type, memb_ptr2, elm->name,
					buf_ptr, size);
			XER_ADVANCE(tmprval.consumed);
			ASN_DEBUG("XER/CHOICE: itdf: code=%d", tmprval.code);
			if(tmprval.code != RC_OK)
				RETURN(tmprval.code);
			assert(_fetch_present_idx(st,
				specs->pres_offset, specs->pres_size) == 0);
			/* Record what we've got */
			_set_present_idx(st,
				specs->pres_offset, specs->pres_size, edx + 1);
			ctx->phase = 3;
			/* Fall through */
		}

		/*
		 * Get the next part of the XML stream.
		 */
		ch_size = xer_next_token(&ctx->context, buf_ptr, size, &ch_type);
		switch(ch_size) {
		case -1: RETURN(RC_FAIL);
		case 0:  RETURN(RC_WMORE);
		default:
			switch(ch_type) {
			case PXER_COMMENT:	/* Got XML comment */
			case PXER_TEXT:		/* Ignore free-standing text */
				XER_ADVANCE(ch_size);	/* Skip silently */
				continue;
			case PXER_TAG:
				break;	/* Check the rest down there */
			}
		}

		tcv = xer_check_tag(buf_ptr, ch_size, xml_tag);

		/* Skip the extensions section */
		if(ctx->phase == 4) {
			ASN_DEBUG("skip_unknown(%d, %ld)",
				tcv, (long)ctx->left);
			switch(xer_skip_unknown(tcv, &ctx->left)) {
			case -1:
				ctx->phase = 5;
				RETURN(RC_FAIL);
				continue;
			case 1:
				ctx->phase = 3;
				/* Fall through */
			case 0:
				XER_ADVANCE(ch_size);
				continue;
			case 2:
				ctx->phase = 3;
				break;
			}
		}

		switch(tcv) {
		case XCT_BOTH:
			break;	/* No CHOICE? */
		case XCT_CLOSING:
			if(ctx->phase != 3)
				break;
			XER_ADVANCE(ch_size);
			ctx->phase = 5;	/* Phase out */
			RETURN(RC_OK);
		case XCT_OPENING:
			if(ctx->phase == 0) {
				XER_ADVANCE(ch_size);
				ctx->phase = 1;	/* Processing body phase */
				continue;
			}
			/* Fall through */
		case XCT_UNKNOWN_OP:
		case XCT_UNKNOWN_BO:

			if(ctx->phase != 1)
				break;	/* Really unexpected */

			/*
			 * Search which inner member corresponds to this tag.
			 */
			for(edx = 0; edx < td->elements_count; edx++) {
				elm = &td->elements[edx];
				tcv = xer_check_tag(buf_ptr,ch_size,elm->name);
				switch(tcv) {
				case XCT_BOTH:
				case XCT_OPENING:
					/*
					 * Process this member.
					 */
					ctx->step = edx;
					ctx->phase = 2;
					break;
				case XCT_UNKNOWN_OP:
				case XCT_UNKNOWN_BO:
					continue;
				default:
					edx = td->elements_count;
					break;	/* Phase out */
				}
				break;
			}
			if(edx != td->elements_count)
				continue;

			/* It is expected extension */
			if(specs->extensible) {
				ASN_DEBUG("Got anticipated extension");
				/*
				 * Check for (XCT_BOTH or XCT_UNKNOWN_BO)
				 * By using a mask. Only record a pure
				 * <opening> tags.
				 */
				if(tcv & XCT_CLOSING) {
					/* Found </extension> without body */
					ctx->phase = 3; /* Terminating */
				} else {
					ctx->left = 1;
					ctx->phase = 4; /* Skip ...'s */
				}
				XER_ADVANCE(ch_size);
				continue;
			}

			/* Fall through */
		default:
			break;
		}

		ASN_DEBUG("Unexpected XML tag in CHOICE");
		break;
	}

	ctx->phase = 5;	/* Phase out, just in case */
	RETURN(RC_FAIL);
}


asn_enc_rval_t
CHOICE_encode_xer(asn_TYPE_descriptor_t *td, void *sptr,
	int ilevel, enum xer_encoder_flags_e flags,
		asn_app_consume_bytes_f *cb, void *app_key) {
	asn_CHOICE_specifics_t *specs=(asn_CHOICE_specifics_t *)td->specifics;
	asn_enc_rval_t er;
	int present;

	if(!sptr)
		_ASN_ENCODE_FAILED;

	/*
	 * Figure out which CHOICE element is encoded.
	 */
	present = _fetch_present_idx(sptr, specs->pres_offset,specs->pres_size);

	if(present <= 0 || present > td->elements_count) {
		_ASN_ENCODE_FAILED;
	}  else {
		asn_enc_rval_t tmper;
		asn_TYPE_member_t *elm = &td->elements[present-1];
		void *memb_ptr;
		const char *mname = elm->name;
		unsigned int mlen = strlen(mname);

		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(void **)((char *)sptr + elm->memb_offset);
			if(!memb_ptr) _ASN_ENCODE_FAILED;
		} else {
			memb_ptr = (void *)((char *)sptr + elm->memb_offset);
		}

		er.encoded = 0;

                if(!(flags & XER_F_CANONICAL)) _i_ASN_TEXT_INDENT(1, ilevel);
		_ASN_CALLBACK3("<", 1, mname, mlen, ">", 1);

		tmper = elm->type->xer_encoder(elm->type, memb_ptr,
				ilevel + 1, flags, cb, app_key);
		if(tmper.encoded == -1) return tmper;

		_ASN_CALLBACK3("</", 2, mname, mlen, ">", 1);

		er.encoded += 5 + (2 * mlen) + tmper.encoded;
	}

	if(!(flags & XER_F_CANONICAL)) _i_ASN_TEXT_INDENT(1, ilevel - 1);

	return er;
cb_failed:
	_ASN_ENCODE_FAILED;
}

int
CHOICE_print(asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
		asn_app_consume_bytes_f *cb, void *app_key) {
	asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
	int present;

	if(!sptr) return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;

	/*
	 * Figure out which CHOICE element is encoded.
	 */
	present = _fetch_present_idx(sptr, specs->pres_offset,specs->pres_size);

	/*
	 * Print that element.
	 */
	if(present > 0 && present <= td->elements_count) {
		asn_TYPE_member_t *elm = &td->elements[present-1];
		const void *memb_ptr;

		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(const void * const *)((const char *)sptr + elm->memb_offset);
			if(!memb_ptr) return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;
		} else {
			memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
		}

		/* Print member's name and stuff */
		if(0) {
			if(cb(elm->name, strlen(elm->name), app_key) < 0
			|| cb(": ", 2, app_key) < 0)
				return -1;
		}

		return elm->type->print_struct(elm->type, memb_ptr, ilevel,
			cb, app_key);
	} else {
		return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;
	}
}

void
CHOICE_free(asn_TYPE_descriptor_t *td, void *ptr, int contents_only) {
	asn_CHOICE_specifics_t *specs = (asn_CHOICE_specifics_t *)td->specifics;
	int present;

	if(!td || !ptr)
		return;

	ASN_DEBUG("Freeing %s as CHOICE", td->name);

	/*
	 * Figure out which CHOICE element is encoded.
	 */
	present = _fetch_present_idx(ptr, specs->pres_offset, specs->pres_size);

	/*
	 * Free that element.
	 */
	if(present > 0 && present <= td->elements_count) {
		asn_TYPE_member_t *elm = &td->elements[present-1];
		void *memb_ptr;

		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(void **)((char *)ptr + elm->memb_offset);
			if(memb_ptr)
				elm->type->free_struct(elm->type, memb_ptr, 0);
		} else {
			memb_ptr = (void *)((char *)ptr + elm->memb_offset);
			elm->type->free_struct(elm->type, memb_ptr, 1);
		}
	}

	if(!contents_only) {
		FREEMEM(ptr);
	}
}


/*
 * The following functions functions offer protection against -fshort-enums,
 * compatible with little- and big-endian machines.
 * If assertion is triggered, either disable -fshort-enums, or add an entry
 * here with the ->pres_size of your target stracture.
 * Unless the target structure is packed, the ".present" member
 * is guaranteed to be aligned properly. ASN.1 compiler itself does not
 * produce packed code.
 */
static int
_fetch_present_idx(const void *struct_ptr, int pres_offset, int pres_size) {
	const void *present_ptr;
	int present;

	present_ptr = ((const char *)struct_ptr) + pres_offset;

	switch(pres_size) {
	case sizeof(int):	present =   *(const int *)present_ptr; break;
	case sizeof(short):	present = *(const short *)present_ptr; break;
	case sizeof(char):	present =  *(const char *)present_ptr; break;
	default:
		/* ANSI C mandates enum to be equivalent to integer */
		assert(pres_size != sizeof(int));
		return 0;	/* If not aborted, pass back safe value */
	}

	return present;
}

static void
_set_present_idx(void *struct_ptr, int pres_offset, int pres_size, int present) {
	void *present_ptr;
	present_ptr = ((char *)struct_ptr) + pres_offset;

	switch(pres_size) {
	case sizeof(int):	*(int *)present_ptr   = present; break;
	case sizeof(short):	*(short *)present_ptr = present; break;
	case sizeof(char):	*(char *)present_ptr  = present; break;
	default:
		/* ANSI C mandates enum to be equivalent to integer */
		assert(pres_size != sizeof(int));
	}
}