si: Implement range 128, 256, 1024 encoding

This commit adds the implementation of these range formats to the
encoder. In addition, the work-around that tried range 512 first is
removed, so that the selection is primarily based on the max distance
between frequencies.

Ticket: OW#1061
Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/libbsc/arfcn_range_encode.c b/openbsc/src/libbsc/arfcn_range_encode.c
index 1a26523..e67bf0a 100644
--- a/openbsc/src/libbsc/arfcn_range_encode.c
+++ b/openbsc/src/libbsc/arfcn_range_encode.c
@@ -270,8 +270,8 @@
 	chan_list[0] = 0x8C;
 	write_orig_arfcn(chan_list, f0);
 
-	LOGP(DRR, LOGL_ERROR, "Range128 encoding is not implemented.\n");
-	return -1;
+	write_all_wn(&chan_list[2], 1, w, 28, 7);
+	return 0;
 }
 
 int range_enc_range256(uint8_t *chan_list, int f0, int *w)
@@ -279,8 +279,8 @@
 	chan_list[0] = 0x8A;
 	write_orig_arfcn(chan_list, f0);
 
-	LOGP(DRR, LOGL_ERROR, "Range256 encoding is not implemented.\n");
-	return -1;
+	write_all_wn(&chan_list[2], 1, w, 21, 8);
+	return 0;
 }
 
 int range_enc_range512(uint8_t *chan_list, int f0, int *w)
@@ -296,8 +296,8 @@
 {
 	chan_list[0] = 0x80 | (f0_included << 2);
 
-	LOGP(DRR, LOGL_ERROR, "Range1024 encoding is not implemented.\n");
-	return -1;
+	write_all_wn(&chan_list[0], 6, w, 16, 10);
+	return 0;
 }
 
 int range_enc_filter_arfcns(int *arfcns,
diff --git a/openbsc/tests/gsm0408/gsm0408_test.ok b/openbsc/tests/gsm0408/gsm0408_test.ok
index dab495d..3d3c4e6 100644
--- a/openbsc/tests/gsm0408/gsm0408_test.ok
+++ b/openbsc/tests/gsm0408/gsm0408_test.ok
@@ -47,20 +47,15 @@
 Decoded freqs 6 (expected 6)
 Decoded: 10 17 31 45 58 79 
 Range test 6: range 1023, num ARFCNs 17
-Cannot encode range, rc = -1
+chan_list = 84 71 e4 ab b9 58 05 cb 39 17 fd b0 75 62 0f 2f 
+Decoded freqs 17 (expected 17)
+Decoded: 0 17 31 45 58 79 81 97 113 127 213 277 287 311 331 391 1023 
 Range test 7: range 1023, num ARFCNs 16
-Cannot encode range, rc = -1
+chan_list = 80 71 e4 ab b9 58 05 cb 39 17 fd b0 75 62 0f 2f 
+Decoded freqs 16 (expected 16)
+Decoded: 17 31 45 58 79 81 97 113 127 213 277 287 311 331 391 1023 
 Random range test: range 127, max num ARFCNs 29
-Cannot encode range, rc = -1
-Failed on test 0, range 127, num ARFCNs 1
-Cannot encode range, rc = -1
 Random range test: range 255, max num ARFCNs 22
-Cannot encode range, rc = -1
-Failed on test 0, range 255, num ARFCNs 1
-Cannot encode range, rc = -1
 Random range test: range 511, max num ARFCNs 18
 Random range test: range 1023, max num ARFCNs 16
-Cannot encode range, rc = -1
-Failed on test 0, range 1023, num ARFCNs 1
-Cannot encode range, rc = -1
 Done.