aboutsummaryrefslogtreecommitdiffstats
path: root/erts/emulator/beam/erl_bif_binary.c
diff options
context:
space:
mode:
authorPatrik Nyblom <[email protected]>2010-04-30 18:17:17 +0200
committerBjörn Gustavsson <[email protected]>2010-05-17 15:51:50 +0200
commitccf8728a95af72aa4847e0844d45dcda991ea435 (patch)
tree1e52543c81f70ba659593b11a6a0918ea95f490f /erts/emulator/beam/erl_bif_binary.c
parent8f21d4026e8f338245812d6edfd113c05282e321 (diff)
downloadotp-ccf8728a95af72aa4847e0844d45dcda991ea435.tar.gz
otp-ccf8728a95af72aa4847e0844d45dcda991ea435.tar.bz2
otp-ccf8728a95af72aa4847e0844d45dcda991ea435.zip
Add binary:{encode,decode}_unsigned({1,2}
Add testcases for encode/decode_unsigned/1,2.
Diffstat (limited to 'erts/emulator/beam/erl_bif_binary.c')
-rw-r--r--erts/emulator/beam/erl_bif_binary.c304
1 files changed, 304 insertions, 0 deletions
diff --git a/erts/emulator/beam/erl_bif_binary.c b/erts/emulator/beam/erl_bif_binary.c
index b3ebc95cea..d073eb072f 100644
--- a/erts/emulator/beam/erl_bif_binary.c
+++ b/erts/emulator/beam/erl_bif_binary.c
@@ -2441,6 +2441,310 @@ BIF_RETTYPE binary_referenced_byte_size_1(BIF_ALIST_1)
BIF_RET(res);
}
+#define END_BIG 0
+#define END_SMALL 1
+
+#ifdef WORDS_BIGENDIAN
+#define END_NATIVE END_BIG
+#else
+#define END_NATIVE END_SMALL
+#endif
+
+static int get_need(Uint u) {
+#if defined(ARCH_64) && !HALFWORD_HEAP
+ if (u > 0xFFFFFFFFUL) {
+ if (u > 0xFFFFFFFFFFFFUL) {
+ if (u > 0xFFFFFFFFFFFFFFUL) {
+ return 8;
+ }
+ return 7;
+ }
+ if (u > 0xFFFFFFFFFFUL) {
+ return 6;
+ }
+ return 5;
+ }
+#endif
+ if (u > 0xFFFFUL) {
+ if (u > 0xFFFFFFUL) {
+ return 4;
+ }
+ return 3;
+ }
+ if (u > 0xFFUL) {
+ return 2;
+ }
+ return 1;
+}
+
+static BIF_RETTYPE do_encode_unsigned(Process *p, Eterm uns, Eterm endianess)
+{
+ Eterm res;
+ if ((is_not_small(uns) && is_not_big(uns)) || is_not_atom(endianess) ||
+ (endianess != am_big && endianess != am_little)) {
+ goto badarg;
+ }
+ if (is_small(uns)) {
+ Sint x = signed_val(uns);
+ Uint u;
+ int n,i;
+ byte *b;
+
+ if (x < 0) {
+ goto badarg;
+ }
+
+ u = (Uint) x;
+ n = get_need(u);
+ ASSERT(n <= ERL_ONHEAP_BIN_LIMIT);
+ res = erts_new_heap_binary(p, NULL, n, &b);
+ if (endianess == am_big) {
+ for(i=n-1;i>=0;--i) {
+ b[i] = u & 0xFF;
+ u >>= 8;
+ }
+ } else {
+ for(i=0;i<n;++i) {
+ b[i] = u & 0xFF;
+ u >>= 8;
+ }
+ }
+ BIF_RET(res);
+ } else {
+ /* Big */
+ Eterm *bigp = big_val(uns);
+ Uint n;
+ dsize_t num_parts = BIG_SIZE(bigp);
+ Eterm res;
+ byte *b;
+ ErtsDigit d;
+
+ if(BIG_SIGN(bigp)) {
+ goto badarg;
+ }
+ n = (num_parts-1)*sizeof(ErtsDigit)+get_need(BIG_DIGIT(bigp,(num_parts-1)));
+ if (n <= ERL_ONHEAP_BIN_LIMIT) {
+ res = erts_new_heap_binary(p,NULL,n,&b);
+ } else {
+ res = erts_new_mso_binary(p,NULL,n);
+ b = ((ProcBin *) binary_val(res))->bytes;
+ }
+
+ if (endianess == am_big) {
+ Sint i,j;
+ j = 0;
+ d = BIG_DIGIT(bigp,0);
+ for (i=n-1;i>=0;--i) {
+ b[i] = d & 0xFF;
+ if (!((++j) % sizeof(ErtsDigit))) {
+ d = BIG_DIGIT(bigp,j / sizeof(ErtsDigit));
+ } else {
+ d >>= 8;
+ }
+ }
+ } else {
+ Sint i,j;
+ j = 0;
+ d = BIG_DIGIT(bigp,0);
+ for (i=0;i<n;++i) {
+ b[i] = d & 0xFF;
+ if (!((++j) % sizeof(ErtsDigit))) {
+ d = BIG_DIGIT(bigp,j / sizeof(ErtsDigit));
+ } else {
+ d >>= 8;
+ }
+ }
+
+ }
+ BIF_RET(res);
+ }
+ badarg:
+ BIF_ERROR(p,BADARG);
+}
+
+static BIF_RETTYPE do_decode_unsigned(Process *p, Eterm uns, Eterm endianess)
+{
+ byte *bytes;
+ Uint bitoffs, bitsize;
+ Uint size;
+ Eterm res;
+
+ if (is_not_binary(uns) || is_not_atom(endianess) ||
+ (endianess != am_big && endianess != am_little)) {
+ goto badarg;
+ }
+ ERTS_GET_BINARY_BYTES(uns, bytes, bitoffs, bitsize);
+ if (bitsize != 0) {
+ goto badarg;
+ }
+ /* align while rolling */
+ size = binary_size(uns);
+ if (bitoffs) {
+ if (endianess == am_big) {
+ while (size && (((((Uint) bytes[0]) << bitoffs) |
+ (((Uint) bytes[1]) >> (8-bitoffs))) & 0xFF) == 0) {
+ ++bytes;
+ --size;
+ }
+ } else {
+ while(size &&
+ (((((Uint) bytes[size-1]) << bitoffs) |
+ (((Uint) bytes[size]) >> (8-bitoffs))) & 0xFF) == 0) {
+ --size;
+ }
+ }
+ } else {
+ if (endianess == am_big) {
+ while (size && *bytes == 0) {
+ ++bytes;
+ --size;
+ }
+ } else {
+ while(size && bytes[size-1] == 0) {
+ --size;
+ }
+ }
+ }
+ if (!size) {
+ BIF_RET(make_small(0));
+ }
+
+ if (size <= sizeof(Uint)) {
+ Uint u = 0;
+ Sint i;
+
+ if (endianess == am_big) {
+ if (bitoffs) {
+ for(i=0;i<size;++i) {
+ u <<=8;
+ u |= (((((Uint) bytes[i]) << bitoffs) |
+ (((Uint) bytes[i+1]) >> (8-bitoffs))) & 0xFF);
+ }
+ } else {
+ for(i=0;i<size;++i) {
+ u <<=8;
+ u |= bytes[i];
+ }
+ }
+ } else {
+
+ if (bitoffs) {
+ for(i=size-1;i>=0;--i) {
+ u <<=8;
+ u |= (((((Uint) bytes[i]) << bitoffs) |
+ (((Uint) bytes[i+1]) >> (8-bitoffs))) & 0xFF);
+ }
+ } else {
+ for(i=size-1;i>=0;--i) {
+ u <<=8;
+ u |= bytes[i];
+ }
+ }
+ }
+ res = erts_make_integer(u,p);
+ BIF_RET(res);
+ } else {
+ /* Assume big, as we stripped away all zeroes from the MSB part of the binary */
+ dsize_t num_parts = size / sizeof(ErtsDigit) + !!(size % sizeof(ErtsDigit));
+ Eterm *bigp;
+
+ bigp = HAlloc(p, BIG_NEED_SIZE(num_parts));
+ *bigp = make_pos_bignum_header(num_parts);
+ res = make_big(bigp);
+
+ if (endianess == am_big) {
+ Sint i,j;
+ ErtsDigit *d;
+ j = size;
+ d = &(BIG_DIGIT(bigp,num_parts - 1));
+ *d = 0;
+ i = 0;
+ if(bitoffs) {
+ for (;;){
+ (*d) <<= 8;
+ (*d) |= (((((Uint) bytes[i]) << bitoffs) |
+ (((Uint) bytes[i+1]) >> (8-bitoffs))) & 0xFF);
+ if (++i >= size) {
+ break;
+ }
+ if (!(--j % sizeof(ErtsDigit))) {
+ --d;
+ *d = 0;
+ }
+ }
+ } else {
+ for (;;){
+ (*d) <<= 8;
+ (*d) |= bytes[i];
+ if (++i >= size) {
+ break;
+ }
+ if (!(--j % sizeof(ErtsDigit))) {
+ --d;
+ *d = 0;
+ }
+ }
+ }
+ } else {
+ Sint i,j;
+ ErtsDigit *d;
+ j = size;
+ d = &(BIG_DIGIT(bigp,num_parts - 1));
+ *d = 0;
+ i = size-1;
+ if (bitoffs) {
+ for (;;){
+ (*d) <<= 8;
+ (*d) |= (((((Uint) bytes[i]) << bitoffs) |
+ (((Uint) bytes[i+1]) >> (8-bitoffs))) & 0xFF);
+ if (--i < 0) {
+ break;
+ }
+ if (!(--j % sizeof(ErtsDigit))) {
+ --d;
+ *d = 0;
+ }
+ }
+ } else {
+ for (;;){
+ (*d) <<= 8;
+ (*d) |= bytes[i];
+ if (--i < 0) {
+ break;
+ }
+ if (!(--j % sizeof(ErtsDigit))) {
+ --d;
+ *d = 0;
+ }
+ }
+ }
+ }
+ BIF_RET(res);
+ }
+ badarg:
+ BIF_ERROR(p,BADARG);
+}
+
+BIF_RETTYPE binary_encode_unsigned_1(BIF_ALIST_1)
+{
+ return do_encode_unsigned(BIF_P,BIF_ARG_1,am_big);
+}
+
+BIF_RETTYPE binary_encode_unsigned_2(BIF_ALIST_2)
+{
+ return do_encode_unsigned(BIF_P,BIF_ARG_1,BIF_ARG_2);
+}
+
+BIF_RETTYPE binary_decode_unsigned_1(BIF_ALIST_1)
+{
+ return do_decode_unsigned(BIF_P,BIF_ARG_1,am_big);
+}
+
+BIF_RETTYPE binary_decode_unsigned_2(BIF_ALIST_2)
+{
+ return do_decode_unsigned(BIF_P,BIF_ARG_1,BIF_ARG_2);
+}
+
/*
* Hard debug functions (dump) for the search structures
*/