per support

skeletons/constr_SEQUENCE_OF.c

 /*-
- * Copyright (c) 2003, 2004 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Copyright (c) 2003, 2004, 2006 Lev Walkin <vlm@lionet.info>.
+ * All rights reserved.
  * Redistribution and modifications are permitted subject to BSD license.
  */
 #include <asn_internal.h>
@@ -139,3 +140,69 @@ cb_failed:
 	_ASN_ENCODE_FAILED;
 }
 
+asn_enc_rval_t
+SEQUENCE_OF_encode_uper(asn_TYPE_descriptor_t *td,
+	asn_per_constraints_t *constraints, void *sptr, asn_per_outp_t *po) {
+	asn_anonymous_sequence_ *list;
+	asn_per_constraint_t *ct;
+	asn_enc_rval_t er;
+	asn_TYPE_member_t *elm = td->elements;
+	int seq;
+
+	if(!sptr) _ASN_ENCODE_FAILED;
+	list = _A_SEQUENCE_FROM_VOID(sptr);
+
+	er.encoded = 0;
+
+	ASN_DEBUG("Encoding %s as SEQUENCE OF (%d)", td->name, list->count);
+
+	if(constraints) ct = &constraints->size;
+	else if(td->per_constraints) ct = &td->per_constraints->size;
+	else ct = 0;
+
+	/* If extensible constraint, check if size is in root */
+	if(ct) {
+		int not_in_root = (list->count < ct->lower_bound
+				|| list->count > ct->upper_bound);
+		ASN_DEBUG("lb %ld ub %ld %s",
+			ct->lower_bound, ct->upper_bound,
+			ct->flags & APC_EXTENSIBLE ? "ext" : "fix");
+		if(ct->flags & APC_EXTENSIBLE) {
+			/* Declare whether size is in extension root */
+			if(per_put_few_bits(po, not_in_root, 1))
+				_ASN_ENCODE_FAILED;
+			if(not_in_root) ct = 0;
+		} else if(not_in_root && ct->effective_bits >= 0)
+			_ASN_ENCODE_FAILED;
+	}
+
+	if(ct && ct->effective_bits >= 0) {
+		/* X.691, #19.5: No length determinant */
+		if(per_put_few_bits(po, list->count - ct->lower_bound,
+				ct->effective_bits))
+			_ASN_ENCODE_FAILED;
+	}
+
+	for(seq = -1; seq < list->count;) {
+		ssize_t mayEncode;
+		if(seq < 0) seq = 0;
+		if(ct && ct->effective_bits >= 0) {
+			mayEncode = list->count;
+		} else {
+			mayEncode = uper_put_length(po, list->count - seq);
+			if(mayEncode < 0) _ASN_ENCODE_FAILED;
+		}
+
+		while(mayEncode--) {
+			void *memb_ptr = list->array[seq++];
+			if(!memb_ptr) _ASN_ENCODE_FAILED;
+			er = elm->type->uper_encoder(elm->type,
+				elm->per_constraints, memb_ptr, po);
+			if(er.encoded == -1)
+				_ASN_ENCODE_FAILED;
+		}
+	}
+
+	_ASN_ENCODED_OK(er);
+}
+

skeletons/constr_SEQUENCE_OF.h

@@ -24,6 +24,7 @@ extern "C" {
 #define	SEQUENCE_OF_decode_uper	SET_OF_decode_uper
 der_type_encoder_f SEQUENCE_OF_encode_der;
 xer_type_encoder_f SEQUENCE_OF_encode_xer;
+per_type_encoder_f SEQUENCE_OF_encode_uper;
 
 #ifdef __cplusplus
 }

skeletons/constr_SET_OF.h

@@ -33,6 +33,7 @@ der_type_encoder_f SET_OF_encode_der;
 xer_type_decoder_f SET_OF_decode_xer;
 xer_type_encoder_f SET_OF_encode_xer;
 per_type_decoder_f SET_OF_decode_uper;
+per_type_encoder_f SET_OF_encode_uper;
 
 #ifdef __cplusplus
 }

skeletons/constr_TYPE.h

 /*-
- * Copyright (c) 2003, 2004, 2005 Lev Walkin <vlm@lionet.info>.
+ * Copyright (c) 2003, 2004, 2005, 2006 Lev Walkin <vlm@lionet.info>.
  * All rights reserved.
  * Redistribution and modifications are permitted subject to BSD license.
  */
@@ -40,6 +40,7 @@ typedef struct asn_struct_ctx_s {
 #include <xer_decoder.h>	/* Decoder of XER (XML, text) */
 #include <xer_encoder.h>	/* Encoder into XER (XML, text) */
 #include <per_decoder.h>	/* Packet Encoding Rules decoder */
+#include <per_encoder.h>	/* Packet Encoding Rules encoder */
 #include <constraints.h>	/* Subtype constraints support */
 
 /*
@@ -97,6 +98,7 @@ typedef struct asn_TYPE_descriptor_s {
 	xer_type_decoder_f *xer_decoder;	/* Generic XER decoder */
 	xer_type_encoder_f *xer_encoder;	/* [Canonical] XER encoder */
 	per_type_decoder_f *uper_decoder;	/* Unaligned PER decoder */
+	per_type_encoder_f *uper_encoder;	/* Unaligned PER encoder */
 
 	/***********************************************************************
 	 * Internally useful members. Not to be used by applications directly. *
@@ -144,7 +146,7 @@ typedef struct asn_TYPE_member_s {
 	asn_TYPE_descriptor_t *type;	/* Member type descriptor */
 	asn_constr_check_f *memb_constraints;	/* Constraints validator */
 	asn_per_constraints_t *per_constraints;	/* PER compiled constraints */
-	int (*default_value)(void **sptr);	/* DEFAULT <value> */
+	int (*default_value)(int setval, void **sptr);	/* DEFAULT <value> */
 	char *name;			/* ASN.1 identifier of the element */
 } asn_TYPE_member_t;
 

skeletons/der_encoder.c

@@ -52,20 +52,19 @@ static int encode_to_buffer_cb(const void *buffer, size_t size, void *key) {
  */
 asn_enc_rval_t
 der_encode_to_buffer(asn_TYPE_descriptor_t *type_descriptor, void *struct_ptr,
-	void *buffer, size_t *buffer_size) {
+	void *buffer, size_t buffer_size) {
 	enc_to_buf_arg arg;
 	asn_enc_rval_t ec;
 
 	arg.buffer = buffer;
-	arg.left = *buffer_size;
+	arg.left = buffer_size;
 
 	ec = type_descriptor->der_encoder(type_descriptor,
 		struct_ptr,	/* Pointer to the destination structure */
 		0, 0, encode_to_buffer_cb, &arg);
 	if(ec.encoded != -1) {
-		assert(ec.encoded == (ssize_t)(*buffer_size - arg.left));
+		assert(ec.encoded == (ssize_t)(buffer_size - arg.left));
 		/* Return the encoded contents size */
-		*buffer_size = ec.encoded;
 	}
 	return ec;
 }

skeletons/der_encoder.h

@@ -27,7 +27,7 @@ asn_enc_rval_t der_encode_to_buffer(
 		struct asn_TYPE_descriptor_s *type_descriptor,
 		void *struct_ptr,	/* Structure to be encoded */
 		void *buffer,		/* Pre-allocated buffer */
-		size_t *buffer_size	/* Initial buffer size (max) */
+		size_t buffer_size	/* Initial buffer size (maximum) */
 	);
 
 /*

skeletons/file-dependencies

@@ -60,6 +60,7 @@ xer_decoder.h xer_decoder.c	# XER decoding support
 xer_encoder.h xer_encoder.c	# XER encoding support
 per_support.h per_support.c	# PER parsing
 per_decoder.h per_decoder.c	# PER decoding support
+per_encoder.h per_encoder.c	# PER encoding support
 #asn-decoder-template.c		# Template for quick decoder creation
 
 CODEC-PER:			# THIS IS A SPECIAL SECTION

skeletons/per_encoder.c

+#include <asn_application.h>
+#include <asn_internal.h>
+#include <per_encoder.h>
+
+/* Flush partially filled buffer */
+static int _uper_encode_flush_outp(asn_per_outp_t *po);
+
+asn_enc_rval_t
+uper_encode(asn_TYPE_descriptor_t *td, void *sptr, asn_app_consume_bytes_f *cb, void *app_key) {
+	asn_per_outp_t po;
+	asn_enc_rval_t er;
+
+	/*
+	 * Invoke type-specific encoder.
+	 */
+	if(!td || !td->uper_encoder)
+		_ASN_ENCODE_FAILED;	/* PER is not compiled in */
+
+	po.buffer = po.tmpspace;
+	po.nboff = 0;
+	po.nbits = 8 * sizeof(po.tmpspace);
+	po.outper = cb;
+	po.op_key = app_key;
+
+	er = td->uper_encoder(td, 0, sptr, &po);
+	if(er.encoded != -1 && _uper_encode_flush_outp(&po))
+		_ASN_ENCODE_FAILED;
+
+	return er;
+}
+
+/*
+ * Argument type and callback necessary for uper_encode_to_buffer().
+ */
+typedef struct enc_to_buf_arg {
+	void *buffer;
+	size_t left;
+} enc_to_buf_arg;
+static int encode_to_buffer_cb(const void *buffer, size_t size, void *key) {
+	enc_to_buf_arg *arg = (enc_to_buf_arg *)key;
+
+	if(arg->left < size)
+		return -1;	/* Data exceeds the available buffer size */
+
+	memcpy(arg->buffer, buffer, size);
+	arg->buffer = ((char *)arg->buffer) + size;
+	arg->left -= size;
+
+	return 0;
+}
+
+asn_enc_rval_t
+uper_encode_to_buffer(asn_TYPE_descriptor_t *td, void *sptr, void *buffer, size_t buffer_size) {
+	enc_to_buf_arg key;
+	asn_enc_rval_t er;
+
+	/*
+	 * Invoke type-specific encoder.
+	 */
+	if(!td || !td->uper_encoder)
+		_ASN_ENCODE_FAILED;	/* PER is not compiled in */
+
+	key.buffer = buffer;
+	key.left = buffer_size;
+
+	ASN_DEBUG("Encoding \"%s\" using UNALIGNED PER", td->name);
+
+	er = uper_encode(td, sptr, encode_to_buffer_cb, &key);
+	if(er.encoded != -1)
+		er.encoded = buffer_size - key.left;
+	return er;
+}
+
+static int
+_uper_encode_flush_outp(asn_per_outp_t *po) {
+	uint8_t *buf;
+
+	if(po->nboff == 0 && po->buffer == po->tmpspace)
+		return 0;
+
+	buf = po->buffer + (po->nboff >> 3);
+	/* Make sure we account for the last, partially filled */
+	if(po->nboff & 0x07) {
+		buf[0] &= 0xff << (8 - (po->nboff & 0x07));
+		buf++;
+	}
+
+	return po->outper(po->tmpspace, buf - po->tmpspace, po->op_key);
+}

skeletons/per_encoder.h

+/*-
+ * Copyright (c) 2006 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#ifndef	_PER_ENCODER_H_
+#define	_PER_ENCODER_H_
+
+#include <asn_application.h>
+#include <per_support.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct asn_TYPE_descriptor_s;	/* Forward declaration */
+
+/*
+ * Unaligned PER encoder of any ASN.1 type. May be invoked by the application.
+ */
+asn_enc_rval_t uper_encode(struct asn_TYPE_descriptor_s *type_descriptor,
+	void *struct_ptr,	/* Structure to be encoded */
+	asn_app_consume_bytes_f *consume_bytes_cb,	/* Data collector */
+	void *app_key		/* Arbitrary callback argument */
+);
+
+/* A variant of uper_encode() which encodes data into the existing buffer */
+asn_enc_rval_t uper_encode_to_buffer(
+	struct asn_TYPE_descriptor_s *type_descriptor,
+	void *struct_ptr,	/* Structure to be encoded */
+	void *buffer,		/* Pre-allocated buffer */
+	size_t buffer_size	/* Initial buffer size (max) */
+);
+
+
+/*
+ * Type of the generic PER encoder function.
+ */
+typedef asn_enc_rval_t (per_type_encoder_f)(
+	struct asn_TYPE_descriptor_s *type_descriptor,
+	asn_per_constraints_t *constraints,
+	void *struct_ptr,
+	asn_per_outp_t *per_output
+);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* _PER_ENCODER_H_ */

skeletons/per_support.c

 /*
- * Copyright (c) 2005 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Copyright (c) 2005, 2006 Lev Walkin <vlm@lionet.info>. All rights reserved.
  * Redistribution and modifications are permitted subject to BSD license.
  */
 #include <asn_system.h>
@@ -80,7 +80,7 @@ per_get_many_bits(asn_per_data_t *pd, uint8_t *dst, int alright, int nbits) {
 		} else {
 			value = per_get_few_bits(pd, nbits);
 			if(value < 0) return -1;
-			if(nbits & 7) {	/* implies alright */
+			if(nbits & 7) {	/* implies left alignment */
 				value <<= 8 - (nbits & 7),
 				nbits += 8 - (nbits & 7);
 				if(nbits > 24)
@@ -150,3 +150,161 @@ uper_get_nsnnwn(asn_per_data_t *pd) {
 
 	return value;
 }
+
+/*
+ * Put the normally small non-negative whole number.
+ * X.691, #10.6
+ */
+int
+uper_put_nsnnwn(asn_per_outp_t *po, int n) {
+	int bytes;
+
+	if(n <= 63) {
+		if(n < 0) return -1;
+		return per_put_few_bits(po, n, 7);
+	}
+	if(n < 256)
+		bytes = 1;
+	else if(n < 65536)
+		bytes = 2;
+	else if(n < 256 * 65536)
+		bytes = 3;
+	else
+		return -1;	/* This is not a "normally small" value */
+	if(per_put_few_bits(po, bytes, 8))
+		return -1;
+
+	return per_put_few_bits(po, n, 8 * bytes);
+}
+
+
+/*
+ * Put a small number of bits (<= 31).
+ */
+int
+per_put_few_bits(asn_per_outp_t *po, uint32_t bits, int obits) {
+	size_t off;	/* Next after last bit offset */
+	size_t omsk;	/* Existing last byte meaningful bits mask */
+	uint8_t *buf;
+
+	if(obits <= 0 || obits >= 32) return obits ? -1 : 0;
+
+	/*
+	 * Normalize position indicator.
+	 */
+	if(po->nboff >= 8) {
+		po->buffer += (po->nboff >> 3);
+		po->nbits  -= (po->nboff & ~0x07);
+		po->nboff  &= 0x07;
+	}
+
+	/*
+	 * Flush whole-bytes output, if necessary.
+	 */
+	if(po->nboff + obits > po->nbits) {
+		int complete_bytes = (po->buffer - po->tmpspace);
+		if(po->outper(po->buffer, complete_bytes, po->op_key) < 0)
+			return -1;
+		if(po->nboff)
+			po->tmpspace[0] = po->buffer[0];
+		po->buffer = po->tmpspace;
+		po->nbits = 8 * sizeof(po->tmpspace);
+	}
+
+	/*
+	 * Now, due to sizeof(tmpspace), we are guaranteed large enough space.
+	 */
+	buf = po->buffer;
+	omsk = ~((1 << (8 - po->nboff)) - 1);
+	off = (po->nboff += obits);
+
+	/* Clear data of debris before meaningful bits */
+	bits &= (((uint32_t)1 << obits) - 1);
+
+	ASN_DEBUG("[PER out %d %u/%x (t=%d,o=%d) %x&%x=%x]", obits, bits, bits,
+		po->nboff - obits, off, buf[0], omsk&0xff, buf[0] & omsk);
+
+	if(off <= 8)	/* Completely within 1 byte */
+		bits <<= (8 - off),
+		buf[0] = (buf[0] & omsk) | bits;
+	else if(off <= 16)
+		bits <<= (16 - off),
+		buf[0] = (buf[0] & omsk) | (bits >> 8),
+		buf[1] = bits;
+	else if(off <= 24)
+		bits <<= (24 - off),
+		buf[0] = (buf[0] & omsk) | (bits >> 16),
+		buf[1] = bits >> 8,
+		buf[2] = bits;
+	else if(off <= 31)
+		bits <<= (32 - off),
+		buf[0] = (buf[0] & omsk) | (bits >> 24),
+		buf[1] = bits >> 16,
+		buf[2] = bits >> 8,
+		buf[3] = bits;
+	else {
+		ASN_DEBUG("->[PER out split %d]", obits);
+		per_put_few_bits(po, bits >> 8, 24);
+		per_put_few_bits(po, bits, obits - 24);
+		ASN_DEBUG("<-[PER out split %d]", obits);
+	}
+
+	ASN_DEBUG("[PER out %u/%x => %02x buf+%d]",
+		bits, bits, buf[0], po->buffer - po->tmpspace);
+
+	return 0;
+}
+
+
+/*
+ * Output a large number of bits.
+ */
+int
+per_put_many_bits(asn_per_outp_t *po, const uint8_t *src, int nbits) {
+
+	while(nbits) {
+		uint32_t value;
+
+		if(nbits >= 24) {
+			value = (src[0] << 16) | (src[1] << 8) | src[2];
+			src += 3;
+			nbits -= 24;
+			if(per_put_few_bits(po, value, 24))
+				return -1;
+		} else {
+			value = src[0];
+			if(nbits > 8)
+				value = (value << 8) | src[1];
+			if(nbits > 16)
+				value = (value << 8) | src[2];
+			if(nbits & 0x07)
+				value >>= (8 - (nbits & 0x07));
+			if(per_put_few_bits(po, value, nbits))
+				return -1;
+			break;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Put the length "n" (or part of it) into the stream.
+ */
+ssize_t
+uper_put_length(asn_per_outp_t *po, size_t length) {
+
+	if(length <= 127)	/* #10.9.3.6 */
+		return per_put_few_bits(po, length, 8)
+			? -1 : (ssize_t)length;
+	else if(length < 16384)	/* #10.9.3.7 */
+		return per_put_few_bits(po, length|0x8000, 16)
+			? -1 : (ssize_t)length;
+
+	length >>= 14;
+	if(length > 4) length = 4;
+
+	return per_put_few_bits(po, 0xC0 | length, 8)
+			? -1 : (ssize_t)(length << 14);
+}
+

skeletons/per_support.h

@@ -12,7 +12,7 @@ extern "C" {
 #endif
 
 /*
- * This structure describes a position inside a PER bit stream.
+ * This structure describes a position inside an incoming PER bit stream.
  */
 typedef struct asn_per_data_s {
  const uint8_t *buffer;	/* Pointer to the octet stream */
@@ -20,6 +20,18 @@ typedef struct asn_per_data_s {
         size_t  nbits;	/* Number of bits in the stream */
 } asn_per_data_t;
 
+/*
+ * This structure supports forming PER output.
+ */
+typedef struct asn_per_outp_s {
+	uint8_t *buffer;	/* Pointer into the (tmpspace) */
+	size_t nboff;		/* Bit offset to the meaningful bit */
+	size_t nbits;		/* Number of bits left in (tmpspace) */
+	uint8_t tmpspace[32];	/* Preliminary storage to hold data */
+	int (*outper)(const void *data, size_t size, void *op_key);
+	void *op_key;
+} asn_per_outp_t;
+
 /*
  * Extract a small number of bits (<= 31) from the specified PER data pointer.
  * This function returns -1 if the specified number of bits could not be
@@ -27,6 +39,9 @@ typedef struct asn_per_data_s {
  */
 int32_t per_get_few_bits(asn_per_data_t *per_data, int get_nbits);
 
+/* Output a small number of bits (<= 31) */
+int per_put_few_bits(asn_per_outp_t *per_data, uint32_t bits, int obits);
+
 /*
  * Extract a large number of bits from the specified PER data pointer.
  * This function returns -1 if the specified number of bits could not be
@@ -35,6 +50,9 @@ int32_t per_get_few_bits(asn_per_data_t *per_data, int get_nbits);
 int per_get_many_bits(asn_per_data_t *pd, uint8_t *dst, int right_align,
 			int get_nbits);
 
+/* Output a large number of bits */
+int per_put_many_bits(asn_per_outp_t *po, const uint8_t *src, int put_nbits);
+
 /*
  * Get the length "n" from the Unaligned PER stream.
  */
@@ -42,11 +60,23 @@ ssize_t uper_get_length(asn_per_data_t *pd,
 			int effective_bound_bits,
 			int *repeat);
 
+/*
+ * Put the length "n" to the Unaligned PER stream.
+ * This function returns the number of units which may be flushed
+ * in the next units saving iteration.
+ */
+ssize_t uper_put_length(asn_per_outp_t *po, size_t whole_length);
+
 /*
  * Get the normally small non-negative whole number.
  */
 ssize_t uper_get_nsnnwn(asn_per_data_t *pd);
 
+/*
+ * Put the normally small non-negative whole number.
+ */
+int uper_put_nsnnwn(asn_per_outp_t *po, int n);
+
 #ifdef __cplusplus
 }
 #endif

skeletons/tests/check-PER.c

 #include <per_support.c>
 #include <assert.h>
 
-int
-main() {
+static void
+check_per_decoding() {
 	uint8_t buf[] = { 0xB7, 0x19, 0x2F, 0xEE, 0xAD };
 	uint8_t tmpbuf[10];
 	int32_t z;
@@ -119,6 +119,102 @@ main() {
 	assert(tmpbuf[2] == buf[2]);
 	assert(tmpbuf[3] == buf[3]);
 	assert(tmpbuf[4] == buf[4]);
+}
+
+static int Ignore(const void *data, size_t size, void *op_key) {
+	return 0;
+}
 
+static void
+check_per_encoding() {
+	asn_per_outp_t po;
+	po.buffer = po.tmpspace;
+	po.nboff = 0;
+	po.nbits = 0;
+	po.outper = Ignore;
+	po.op_key = 0;
+	po.tmpspace[0] = 0xff;
+	int ret;
+
+	ret = per_put_few_bits(&po, 0, 0);
+	assert(ret == 0);
+	assert(po.nboff == 0);
+	assert(po.buffer == po.tmpspace);
+	assert(po.tmpspace[0] == 0xff);
+
+	ret = per_put_few_bits(&po, 0, 1);
+	assert(ret == 0);
+	assert(po.nboff == 1);
+	assert(po.nbits == 8 * sizeof(po.tmpspace));
+	assert(po.buffer == po.tmpspace);
+	assert(po.tmpspace[0] == 0x00);
+
+	ret = per_put_few_bits(&po, 1, 1);
+	assert(ret == 0);
+	assert(po.nboff == 2);
+	assert(po.nbits == 8 * sizeof(po.tmpspace));
+	assert(po.buffer == po.tmpspace);
+	assert(po.tmpspace[0] == 0x40);
+
+	ret = per_put_few_bits(&po, 1, 1);
+	assert(ret == 0);
+	assert(po.nboff == 3);
+	assert(po.nbits == 8 * sizeof(po.tmpspace));
+	assert(po.buffer == po.tmpspace);
+	assert(po.tmpspace[0] == 0x60);
+
+	ret = per_put_few_bits(&po, 15, 5);
+	assert(ret == 0);
+	assert(po.nboff == 8);
+	assert(po.nbits == 8 * sizeof(po.tmpspace));
+	assert(po.buffer == po.tmpspace);
+	assert(po.tmpspace[0] == 0x6F);
+
+	ret = per_put_few_bits(&po, 0xf0ff, 16);
+	assert(ret == 0);
+	assert(po.nboff == 16);
+	assert(po.nbits == 8 * sizeof(po.tmpspace) - 8);
+	assert(po.buffer == po.tmpspace + 1);
+	assert(po.tmpspace[0] == 0x6F);
+	assert(po.tmpspace[1] == 0xf0);
+	assert(po.tmpspace[2] == 0xff);
+
+	po.nboff--;
+
+	ret = per_put_few_bits(&po, 2, 1);
+	assert(ret == 0);
+	assert(po.nboff == 8);
+	assert(po.nbits == 8 * sizeof(po.tmpspace) - 16);
+	assert(po.buffer == po.tmpspace + 2);
+	assert(po.tmpspace[0] == 0x6F);
+	assert(po.tmpspace[1] == 0xf0);
+	assert(po.tmpspace[2] == 0xfe);
+
+	ret = per_put_few_bits(&po, 2, 32);
+	assert(ret == -1);
+
+	ret = per_put_few_bits(&po, 2, -1);
+	assert(ret == -1);
+
+	ret = per_put_few_bits(&po, -1, 31);
+	assert(ret == 0);
+	assert(po.nboff == 31);
+	assert(po.nbits == 8 * sizeof(po.tmpspace) - 24);
+	assert(po.buffer == po.tmpspace + 3);
+	assert(po.tmpspace[0] == 0x6F);
+	assert(po.tmpspace[1] == 0xf0);
+	assert(po.tmpspace[2] == 0xfe);
+	assert(po.tmpspace[3] == 0xff);
+	assert(po.tmpspace[4] == 0xff);
+	assert(po.tmpspace[5] == 0xff);
+	assert(po.tmpspace[6] == 0xfe);
+
+
+}
+
+int
+main() {
+	check_per_decoding();
+	check_per_encoding();
 	return 0;
 }