abstract out sorting

skeletons/constr_SET_OF.c

@@ -271,42 +271,130 @@ SET_OF_decode_ber(const asn_codec_ctx_t *opt_codec_ctx,
 struct _el_buffer {
 	uint8_t *buf;
 	size_t length;
-	size_t size;
+	size_t allocated_size;
+    unsigned bits_unused;
 };
 /* Append bytes to the above structure */
 static int _el_addbytes(const void *buffer, size_t size, void *el_buf_ptr) {
-	struct _el_buffer *el_buf = (struct _el_buffer *)el_buf_ptr;
+    struct _el_buffer *el_buf = (struct _el_buffer *)el_buf_ptr;
 
-	if(el_buf->length + size > el_buf->size)
-		return -1;
+    if(el_buf->length + size > el_buf->allocated_size) {
+        size_t new_size;
+        void *p;
 
-	memcpy(el_buf->buf + el_buf->length, buffer, size);
+        new_size = el_buf->allocated_size ? 2 * el_buf->allocated_size : 16;
 
-	el_buf->length += size;
-	return 0;
+        p = REALLOC(el_buf->buf, new_size);
+        if(p) {
+            el_buf->buf = p;
+            el_buf->allocated_size = new_size;
+        } else {
+            return -1;
+        }
+    }
+
+    memcpy(el_buf->buf + el_buf->length, buffer, size);
+
+    el_buf->length += size;
+    return 0;
 }
 static int _el_buf_cmp(const void *ap, const void *bp) {
-	const struct _el_buffer *a = (const struct _el_buffer *)ap;
-	const struct _el_buffer *b = (const struct _el_buffer *)bp;
-	int ret;
-	size_t common_len;
-
-	if(a->length < b->length)
-		common_len = a->length;
-	else
-		common_len = b->length;
-
-	ret = memcmp(a->buf, b->buf, common_len);
-	if(ret == 0) {
-		if(a->length < b->length)
-			ret = -1;
-		else if(a->length > b->length)
-			ret = 1;
+    const struct _el_buffer *a = (const struct _el_buffer *)ap;
+    const struct _el_buffer *b = (const struct _el_buffer *)bp;
+    size_t common_len;
+    int ret;
+
+    if(a->length < b->length)
+        common_len = a->length;
+    else
+        common_len = b->length;
+
+    ret = memcmp(a->buf, b->buf, common_len);
+    if(ret == 0) {
+        if(a->length < b->length)
+            ret = -1;
+        else if(a->length > b->length)
+            ret = 1;
+        /* Ignore unused bits. */
+        if(a->length) {
+            assert((a->buf[a->length-1] & ~(0xff << a->bits_unused)) == 0);
+            assert((b->buf[b->length-1] & ~(0xff << b->bits_unused)) == 0);
+        } else {
+            assert(a->bits_unused == 0);
+            assert(b->bits_unused == 0);
+        }
+    }
+
+    return ret;
+}
+
+static void
+SET_OF__encode_sorted_free(struct _el_buffer *el_buf, size_t count) {
+    size_t i;
+
+    for(i = 0; i < count; i++) {
+        FREEMEM(el_buf[i].buf);
+    }
+
+    FREEMEM(el_buf);
+}
+
+enum SET_OF__encode_method {
+    SOES_DER
+};
+
+static struct _el_buffer *
+SET_OF__encode_sorted(const asn_TYPE_member_t *elm,
+                      const asn_anonymous_set_ *list,
+                      enum SET_OF__encode_method method) {
+    static struct _el_buffer *encoded_els;
+    int edx;
+
+    encoded_els =
+        (struct _el_buffer *)CALLOC(list->count, sizeof(encoded_els[0]));
+    if(encoded_els == NULL) {
+        return NULL;
+    }
+
+	/*
+	 * Encode all members.
+	 */
+    for(edx = 0; edx < list->count; edx++) {
+        const void *memb_ptr = list->array[edx];
+        struct _el_buffer *encoded_el = &encoded_els[edx];
+        asn_enc_rval_t erval;
+
+        if(!memb_ptr) break;
+
+        /*
+		 * Encode the member into the prepared space.
+		 */
+        switch(method) {
+        case SOES_DER:
+            erval = elm->type->op->der_encoder(elm->type, memb_ptr, 0, elm->tag,
+                                               _el_addbytes, encoded_el);
+            break;
+        default:
+            assert(!"Unreachable");
+            break;
+        }
+        if(erval.encoded < 0) break;
 	}
 
-	return ret;
+    if(edx == list->count) {
+        /*
+         * Sort the encoded elements according to their encoding.
+         */
+        qsort(encoded_els, list->count, sizeof(encoded_els[0]), _el_buf_cmp);
+
+        return encoded_els;
+    } else {
+        SET_OF__encode_sorted_free(encoded_els, edx);
+        return NULL;
+    }
 }
 
+
 /*
  * The DER encoder of the SET OF type.
  */
@@ -315,134 +403,78 @@ SET_OF_encode_der(const asn_TYPE_descriptor_t *td, const void *sptr,
                   int tag_mode, ber_tlv_tag_t tag, asn_app_consume_bytes_f *cb,
                   void *app_key) {
     const asn_TYPE_member_t *elm = td->elements;
-	const asn_TYPE_descriptor_t *elm_type = elm->type;
-	der_type_encoder_f *der_encoder = elm_type->op->der_encoder;
     const asn_anonymous_set_ *list = _A_CSET_FROM_VOID(sptr);
     size_t computed_size = 0;
-	ssize_t encoding_size = 0;
-	struct _el_buffer *encoded_els;
-	ssize_t eels_count = 0;
-	size_t max_encoded_len = 1;
-	asn_enc_rval_t erval;
-	int ret;
-	int edx;
+    ssize_t encoding_size = 0;
+    struct _el_buffer *encoded_els;
+    int edx;
 
 	ASN_DEBUG("Estimating size for SET OF %s", td->name);
 
-	/*
-	 * Gather the length of the underlying members sequence.
-	 */
-	for(edx = 0; edx < list->count; edx++) {
-		void *memb_ptr = list->array[edx];
-		if(!memb_ptr) continue;
-        erval = der_encoder(elm_type, memb_ptr, 0, elm->tag, 0, 0);
-        if(erval.encoded == -1)
-			return erval;
-		computed_size += erval.encoded;
-
-		/* Compute maximum encoding's size */
-		if(max_encoded_len < (size_t)erval.encoded)
-			max_encoded_len = erval.encoded;
-	}
-
-	/*
-	 * Encode the TLV for the sequence itself.
-	 */
-	encoding_size = der_write_tags(td, computed_size, tag_mode, 1, tag,
-		cb, app_key);
-	if(encoding_size == -1) {
-		erval.encoded = -1;
-		erval.failed_type = td;
-		erval.structure_ptr = sptr;
-		return erval;
+    /*
+     * Gather the length of the underlying members sequence.
+     */
+    for(edx = 0; edx < list->count; edx++) {
+        void *memb_ptr = list->array[edx];
+        asn_enc_rval_t erval;
+
+        if(!memb_ptr) ASN__ENCODE_FAILED;
+
+        erval =
+            elm->type->op->der_encoder(elm->type, memb_ptr, 0, elm->tag, 0, 0);
+        if(erval.encoded == -1) return erval;
+        computed_size += erval.encoded;
 	}
-	computed_size += encoding_size;
 
-	if(!cb || list->count == 0) {
-		erval.encoded = computed_size;
-		ASN__ENCODED_OK(erval);
-	}
 
-	/*
-	 * DER mandates dynamic sorting of the SET OF elements
-	 * according to their encodings. Build an array of the
-	 * encoded elements.
-	 */
-    encoded_els =
-        (struct _el_buffer *)MALLOC(list->count * sizeof(encoded_els[0]));
-    if(encoded_els == NULL) {
+    /*
+     * Encode the TLV for the sequence itself.
+     */
+    encoding_size =
+        der_write_tags(td, computed_size, tag_mode, 1, tag, cb, app_key);
+    if(encoding_size < 0) {
         ASN__ENCODE_FAILED;
     }
+    computed_size += encoding_size;
 
-    ASN_DEBUG("Encoding members of %s SET OF", td->name);
-
-	/*
-	 * Encode all members.
-	 */
-	for(edx = 0; edx < list->count; edx++) {
-		const void *memb_ptr = list->array[edx];
-		struct _el_buffer *encoded_el = &encoded_els[eels_count];
-
-		if(!memb_ptr) continue;
+    if(!cb || list->count == 0) {
+        asn_enc_rval_t erval;
+        erval.encoded = computed_size;
+        ASN__ENCODED_OK(erval);
+    }
 
-		/*
-		 * Prepare space for encoding.
-		 */
-		encoded_el->buf = (uint8_t *)MALLOC(max_encoded_len);
-		if(encoded_el->buf) {
-			encoded_el->length = 0;
-			encoded_el->size = max_encoded_len;
-		} else {
-			for(edx--; edx >= 0; edx--)
-				FREEMEM(encoded_els[edx].buf);
-			FREEMEM(encoded_els);
-            ASN__ENCODE_FAILED;
-		}
+    ASN_DEBUG("Encoding members of %s SET OF", td->name);
 
-		/*
-		 * Encode the member into the prepared space.
-		 */
-		erval = der_encoder(elm_type, memb_ptr, 0, elm->tag,
-			_el_addbytes, encoded_el);
-		if(erval.encoded == -1) {
-			for(; edx >= 0; edx--)
-				FREEMEM(encoded_els[edx].buf);
-			FREEMEM(encoded_els);
-			return erval;
-		}
-		encoding_size += erval.encoded;
-		eels_count++;
-	}
+    /*
+     * DER mandates dynamic sorting of the SET OF elements
+     * according to their encodings. Build an array of the
+     * encoded elements.
+     */
+    encoded_els = SET_OF__encode_sorted(elm, list, SOES_DER);
 
-	/*
-	 * Sort the encoded elements according to their encoding.
-	 */
-	qsort(encoded_els, eels_count, sizeof(encoded_els[0]), _el_buf_cmp);
+    /*
+     * Report encoded elements to the application.
+     * Dispose of temporary sorted members table.
+     */
+    for(edx = 0; edx < list->count; edx++) {
+        struct _el_buffer *encoded_el = &encoded_els[edx];
+        /* Report encoded chunks to the application */
+        if(cb(encoded_el->buf, encoded_el->length, app_key) < 0) {
+            break;
+        } else {
+            encoding_size += encoded_el->length;
+        }
+    }
 
-	/*
-	 * Report encoded elements to the application.
-	 * Dispose of temporary sorted members table.
-	 */
-	ret = 0;
-	for(edx = 0; edx < eels_count; edx++) {
-		struct _el_buffer *encoded_el = &encoded_els[edx];
-		/* Report encoded chunks to the application */
-		if(ret == 0
-		&& cb(encoded_el->buf, encoded_el->length, app_key) < 0)
-			ret = -1;
-		FREEMEM(encoded_el->buf);
-	}
-	FREEMEM(encoded_els);
+    SET_OF__encode_sorted_free(encoded_els, list->count);
 
-	if(ret || computed_size != (size_t)encoding_size) {
-		/*
-		 * Standard callback failed, or
-		 * encoded size is not equal to the computed size.
-		 */
-        ASN__ENCODE_FAILED;
-	} else {
-		erval.encoded = computed_size;
+    if(edx == list->count) {
+        assert(computed_size == (size_t)encoding_size);
+        asn_enc_rval_t erval;
+        erval.encoded = computed_size;
         ASN__ENCODED_OK(erval);
+    } else {
+        ASN__ENCODE_FAILED;
     }
 }