diff options
| -rw-r--r-- | buf.c | 99 | ||||
| -rw-r--r-- | buf.h | 3 | ||||
| -rw-r--r-- | tests/012/buf.tl | 69 | ||||
| -rw-r--r-- | txr.1 | 44 |
4 files changed, 215 insertions, 0 deletions
@@ -1529,6 +1529,102 @@ val buf_fash(val buf, val bits) abort(); } +val buf_and(val bufa, val bufb) +{ + val self = lit("buf-and"); + struct buf *ab = buf_handle(bufa, self); + struct buf *bb = buf_handle(bufb, self); + ucnum la = c_unum(ab->len, self); + ucnum lb = c_unum(bb->len, self); + + if (la == 0) { + return make_buf(bb->len, zero, bb->len); + } else if (lb == 0) { + return make_buf(ab->len, zero, ab->len); + } else if (la < lb) { + return buf_and(bufb, bufa); + } else if (la == convert(ucnum, -1)) { + err_oflow(self); + abort(); + } else { + val obuf = make_ubuf(la); + ucnum delta = la - lb; + ucnum i; + struct buf *ob = buf_handle(obuf, self); + + memset(ob->data, 0, delta); + + for (i = 0; i < lb; i++) + ob->data[i + delta] = ab->data[i + delta] & bb->data[i]; + + return obuf; + } +} + +val buf_or(val bufa, val bufb) +{ + val self = lit("buf-or"); + struct buf *ab = buf_handle(bufa, self); + struct buf *bb = buf_handle(bufb, self); + ucnum la = c_unum(ab->len, self); + ucnum lb = c_unum(bb->len, self); + + if (la == 0) { + return bufb; + } else if (lb == 0) { + return bufa; + } else if (la < lb) { + return buf_or(bufb, bufa); + } else if (la == convert(ucnum, -1)) { + err_oflow(self); + abort(); + } else { + val obuf = make_ubuf(la); + ucnum delta = la - lb; + ucnum i; + struct buf *ob = buf_handle(obuf, self); + + memcpy(ob->data, ab->data, delta); + + for (i = 0; i < lb; i++) + ob->data[i + delta] = ab->data[i + delta] | bb->data[i]; + + return obuf; + } +} + +val buf_xor(val bufa, val bufb) +{ + val self = lit("buf-xor"); + struct buf *ab = buf_handle(bufa, self); + struct buf *bb = buf_handle(bufb, self); + ucnum la = c_unum(ab->len, self); + ucnum lb = c_unum(bb->len, self); + + if (la == 0) { + return bufb; + } else if (lb == 0) { + return bufa; + } else if (la < lb) { + return buf_xor(bufb, bufa); + } else if (la == convert(ucnum, -1)) { + err_oflow(self); + abort(); + } else { + val obuf = make_ubuf(la); + ucnum delta = la - lb; + ucnum i; + struct buf *ob = buf_handle(obuf, self); + + memcpy(ob->data, ab->data, delta); + + for (i = 0; i < lb; i++) + ob->data[i + delta] = ab->data[i + delta] ^ bb->data[i]; + + return obuf; + } +} + void buf_init(void) { reg_fun(intern(lit("make-buf"), user_package), func_n3o(make_buf, 1)); @@ -1624,6 +1720,9 @@ void buf_init(void) reg_fun(intern(lit("buf-ash"), user_package), func_n2(buf_ash)); reg_fun(intern(lit("buf-fash"), user_package), func_n2(buf_fash)); + reg_fun(intern(lit("buf-and"), user_package), func_n2(buf_and)); + reg_fun(intern(lit("buf-or"), user_package), func_n2(buf_or)); + reg_fun(intern(lit("buf-xor"), user_package), func_n2(buf_xor)); fill_stream_ops(&buf_strm_ops); } @@ -126,5 +126,8 @@ void buf_swap32(val buf); val buf_ash(val buf, val bits); val buf_fash(val buf, val bits); +val buf_and(val bufa, val bufb); +val buf_or(val bufa, val bufb); +val buf_xor(val bufa, val bufb); void buf_init(void); diff --git a/tests/012/buf.tl b/tests/012/buf.tl index 4311e760..f6c35ac7 100644 --- a/tests/012/buf.tl +++ b/tests/012/buf.tl @@ -204,3 +204,72 @@ (mtest (buf-fash #b'deadcafef00d' 4) #b'eadcafef00d0' (buf-fash #b'deadcafef00d' -4) #b'0deadcafef00') + +(mtest + (buf-and #b'' #b'') #b'' + (buf-and #b'' #b'00') #b'00' + (buf-and #b'' #b'11') #b'00' + (buf-and #b'00' #b'00') #b'00' + (buf-and #b'ff' #b'00') #b'00' + (buf-and #b'00' #b'ff') #b'00' + (buf-and #b'aa' #b'ff') #b'aa' + (buf-and #b'ff' #b'aa') #b'aa' + (buf-and #b'ff55' #b'aa') #b'0000' + (buf-and #b'ff00' #b'00') #b'0000' + (buf-and #b'ffff' #b'00') #b'0000' + (buf-and #b'ff00' #b'ff') #b'0000' + (buf-and #b'ffaa' #b'ff') #b'00aa' + (buf-and #b'ffff' #b'aa') #b'00aa' + (buf-and #b'ff55' #b'aa') #b'0000' + (buf-and #b'00' #b'ff00') #b'0000' + (buf-and #b'ff' #b'ff00') #b'0000' + (buf-and #b'00' #b'ffff') #b'0000' + (buf-and #b'aa' #b'ffff') #b'00aa' + (buf-and #b'ff' #b'ffaa') #b'00aa' + (buf-and #b'ff00ff0f' #b'1baddeadbeef') #b'0000de00be0f') + +(mtest + (buf-or #b'' #b'') #b'' + (buf-or #b'' #b'00') #b'00' + (buf-or #b'' #b'11') #b'11' + (buf-or #b'00' #b'00') #b'00' + (buf-or #b'ff' #b'00') #b'ff' + (buf-or #b'00' #b'ff') #b'ff' + (buf-or #b'aa' #b'ff') #b'ff' + (buf-or #b'ff' #b'aa') #b'ff' + (buf-or #b'ff55' #b'aa') #b'ffff' + (buf-or #b'ff00' #b'00') #b'ff00' + (buf-or #b'ffff' #b'00') #b'ffff' + (buf-or #b'ff00' #b'ff') #b'ffff' + (buf-or #b'ffaa' #b'ff') #b'ffff' + (buf-or #b'ffff' #b'aa') #b'ffff' + (buf-or #b'ff55' #b'aa') #b'ffff' + (buf-or #b'00' #b'ff00') #b'ff00' + (buf-or #b'ff' #b'ff00') #b'ffff' + (buf-or #b'00' #b'ffff') #b'ffff' + (buf-or #b'aa' #b'ffff') #b'ffff' + (buf-or #b'ff' #b'ffaa') #b'ffff' + (buf-or #b'ff00ff0f' #b'1baddeadbeef') #b'1badffadffef') + +(mtest + (buf-xor #b'' #b'') #b'' + (buf-xor #b'' #b'00') #b'00' + (buf-xor #b'' #b'11') #b'11' + (buf-xor #b'00' #b'00') #b'00' + (buf-xor #b'ff' #b'00') #b'ff' + (buf-xor #b'00' #b'ff') #b'ff' + (buf-xor #b'aa' #b'ff') #b'55' + (buf-xor #b'ff' #b'aa') #b'55' + (buf-xor #b'ff55' #b'aa') #b'ffff' + (buf-xor #b'ff00' #b'00') #b'ff00' + (buf-xor #b'ffff' #b'00') #b'ffff' + (buf-xor #b'ff00' #b'ff') #b'ffff' + (buf-xor #b'ffaa' #b'ff') #b'ff55' + (buf-xor #b'ffff' #b'aa') #b'ff55' + (buf-xor #b'ff55' #b'aa') #b'ffff' + (buf-xor #b'00' #b'ff00') #b'ff00' + (buf-xor #b'ff' #b'ff00') #b'ffff' + (buf-xor #b'00' #b'ffff') #b'ffff' + (buf-xor #b'aa' #b'ffff') #b'ff55' + (buf-xor #b'ff' #b'ffaa') #b'ff55' + (buf-xor #b'ff00ff0f' #b'1baddeadbeef') #b'1bad21ad41e0') @@ -30273,6 +30273,50 @@ length is equal to that of Shifting an empty buffer by any number of bits results in an empty buffer. +.coNP Functions @, buf-and @ buf-or and @ buf-xor +.synb +.mets (buf-and < buf1 << buf2 ) +.mets (buf-or < buf1 << buf2 ) +.mets (buf-xor < buf1 << buf2 ) +.syne +.desc +The functions +.codn buf-and , +.code buf-or +or +.code buf-xor +perform common bitwise Boolean operations on a pair of buffers, +returning the result as a buffer. + +If the input operands +.meta buf1 +and +.meta buf2 +are of unequal lengths, the returned buffer exhibits the longer +of the two lengths. + +The operands are considered to be aligned together so that their rightmost +bytes correspond. For the purposes of each of these tree operations, the +shorter operand is considered to be padded on the left with null bytes, +which correspond with the leftmost bytes of the longer operand. + +If the returned buffer is the same as either +.meta buf1 +or +.meta buf2 +then that input buffer itself may be returned. + +The +code buf-and +function calculates the bitwise Boolean "and" operation between +corresponding bytes of the two operands; +.code buf-or +calculates the bitwise Boolean "or" operation; +and +.code buf-xor +calculates the bitwise Boolean exclusive "or". + + .coNP Functions @ buf-compress and @ buf-decompress .synb .mets (buf-compress < buf <> [ level ]) |