1 ////////////////////////////////////////////////////////////////////////
2 //
3 // Copyright (C) 2008-2021 The Octave Project Developers
4 //
5 // See the file COPYRIGHT.md in the top-level directory of this
6 // distribution or <https://octave.org/copyright/>.
7 //
8 // This file is part of Octave.
9 //
10 // Octave is free software: you can redistribute it and/or modify it
11 // under the terms of the GNU General Public License as published by
12 // the Free Software Foundation, either version 3 of the License, or
13 // (at your option) any later version.
14 //
15 // Octave is distributed in the hope that it will be useful, but
16 // WITHOUT ANY WARRANTY; without even the implied warranty of
17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 // GNU General Public License for more details.
19 //
20 // You should have received a copy of the GNU General Public License
21 // along with Octave; see the file COPYING. If not, see
22 // <https://www.gnu.org/licenses/>.
23 //
24 ////////////////////////////////////////////////////////////////////////
25
26 #if defined (HAVE_CONFIG_H)
27 # include "config.h"
28 #endif
29
30 #include "defun.h"
31 #include "error.h"
32 #include "errwarn.h"
33 #include "mach-info.h"
34 #include "ov.h"
35 #include "ovl.h"
36 #include "utils.h"
37
38 static inline bool
is_little_endian(bool is_float)39 is_little_endian (bool is_float)
40 {
41 return ((is_float && (octave::mach_info::native_float_format ()
42 == octave::mach_info::flt_fmt_ieee_little_endian))
43 || octave::mach_info::words_little_endian ());
44 }
45
46 static uint8_t
hex2nibble(unsigned char ch)47 hex2nibble (unsigned char ch)
48 {
49 unsigned char val = 0;
50
51 if (! isxdigit (ch))
52 error ("hex2num: invalid character '%c' found in string S", ch);
53
54 if (ch >= 'a')
55 val = static_cast<unsigned char> (ch - 'a' + 10);
56 else if (ch >= 'A')
57 val = static_cast<unsigned char> (ch - 'A' + 10);
58 else
59 val = static_cast<unsigned char> (ch - '0');
60
61 return val;
62 }
63
64 static void
hex2num(const std::string & hex,void * num,std::size_t nbytes,bool swap_bytes)65 hex2num (const std::string& hex, void *num, std::size_t nbytes, bool swap_bytes)
66 {
67 unsigned char *cp = reinterpret_cast<unsigned char *> (num);
68
69 const std::size_t nc = hex.length ();
70 const std::size_t nchars = 2 * nbytes;
71
72 if (nc > nchars)
73 error ("hex2num: S must be no more than %zd characters", nchars);
74
75 std::size_t j = 0;
76
77 for (std::size_t i = 0; i < nbytes; i++)
78 {
79 std::size_t k = (swap_bytes ? nbytes - i - 1 : i);
80
81 unsigned char ch1 = (j < nc) ? hex[j++] : '0';
82 unsigned char ch2 = (j < nc) ? hex[j++] : '0';
83
84 cp[k] = (hex2nibble (ch1) << 4) + hex2nibble (ch2);
85 }
86 }
87
88 template <typename T>
89 Array<T>
hex2num(const Array<std::string> & val,bool swap_bytes)90 hex2num (const Array<std::string>& val, bool swap_bytes)
91 {
92 octave_idx_type nel = val.numel ();
93
94 Array<T> m (val.dims ());
95
96 std::size_t nbytes = sizeof (T);
97
98 for (octave_idx_type i = 0; i < nel; i++)
99 {
100 T num;
101
102 hex2num (val.xelem (i), &num, nbytes, swap_bytes);
103
104 m(i) = num;
105 }
106
107 return m;
108 }
109
110 DEFUN (hex2num, args, ,
111 doc: /* -*- texinfo -*-
112 @deftypefn {} {@var{n} =} hex2num (@var{s})
113 @deftypefnx {} {@var{n} =} hex2num (@var{s}, @var{class})
114 Typecast a hexadecimal character array or cell array of strings to an
115 array of numbers.
116
117 By default, the input array is interpreted as a hexadecimal number
118 representing a double precision value. If fewer than 16 characters are
119 given the strings are right padded with @qcode{'0'} characters.
120
121 Given a string matrix, @code{hex2num} treats each row as a separate number.
122
123 @example
124 @group
125 hex2num (["4005bf0a8b145769"; "4024000000000000"])
126 @result{} [2.7183; 10.000]
127 @end group
128 @end example
129
130 The optional second argument @var{class} may be used to cause the input
131 array to be interpreted as a different value type. Possible values are
132
133 @multitable {Option} {Characters}
134 @headitem Option @tab Characters
135 @item @qcode{"int8"} @tab 2
136 @item @qcode{"uint8"} @tab 2
137 @item @qcode{"int16"} @tab 4
138 @item @qcode{"uint16"} @tab 4
139 @item @qcode{"int32"} @tab 8
140 @item @qcode{"uint32"} @tab 8
141 @item @qcode{"int64"} @tab 16
142 @item @qcode{"uint64"} @tab 16
143 @item @qcode{"char"} @tab 2
144 @item @qcode{"single"} @tab 8
145 @item @qcode{"double"} @tab 16
146 @end multitable
147
148 For example:
149
150 @example
151 @group
152 hex2num (["402df854"; "41200000"], "single")
153 @result{} [2.7183; 10.000]
154 @end group
155 @end example
156 @seealso{num2hex, hex2dec, dec2hex}
157 @end deftypefn */)
158 {
159 octave_value retval;
160
161 int nargin = args.length ();
162
163 if (nargin < 1 || nargin > 2)
164 print_usage ();
165
166 std::string type = "double";
167 if (nargin == 2)
168 type = args(1).xstring_value ("hex2num: CLASS must be a string");
169
170 Array<std::string> val = args(0).cellstr_value ();
171
172 // We always use big-endian order for hex digits.
173 bool is_float = type == "single" || type == "double";
174 bool swap_bytes = is_little_endian (is_float);
175
176 if (type == "int8")
177 retval = octave_value (hex2num<octave_int8> (val, swap_bytes));
178 else if (type == "uint8")
179 retval = octave_value (hex2num<octave_uint8> (val, swap_bytes));
180 else if (type == "int16")
181 retval = octave_value (hex2num<octave_int16> (val, swap_bytes));
182 else if (type == "uint16")
183 retval = octave_value (hex2num<octave_uint16> (val, swap_bytes));
184 else if (type == "int32")
185 retval = octave_value (hex2num<octave_int32> (val, swap_bytes));
186 else if (type == "uint32")
187 retval = octave_value (hex2num<octave_uint32> (val, swap_bytes));
188 else if (type == "int64")
189 retval = octave_value (hex2num<octave_int64> (val, swap_bytes));
190 else if (type == "uint64")
191 retval = octave_value (hex2num<octave_uint64> (val, swap_bytes));
192 else if (type == "char")
193 retval = octave_value (hex2num<char> (val, swap_bytes));
194 else if (type == "single")
195 retval = octave_value (hex2num<float> (val, swap_bytes));
196 else if (type == "double")
197 retval = octave_value (hex2num<double> (val, swap_bytes));
198 else
199 error ("hex2num: unrecognized CLASS '%s'", type.c_str ());
200
201 return retval;
202 }
203
204 /*
205 %!assert (hex2num (["c00";"bff";"000";"3ff";"400"]), [-2:2]')
206 %!assert (hex2num (["c00";"bf8";"000";"3f8";"400"], "single"), single([-2:2])')
207 %!assert (hex2num ("ff", "uint8"), intmax ("uint8"))
208 %!assert (hex2num ("ffff", "uint16"), intmax ("uint16"))
209 %!assert (hex2num ("ffffffff", "uint32"), intmax ("uint32"))
210 %!assert (hex2num ("ffffffff", "uint32"), intmax ("uint32"))
211 %!assert (hex2num ("ffffffffffffffff", "uint64"), intmax ("uint64"))
212 */
213
214 static inline unsigned char
nibble2hex(unsigned char ch)215 nibble2hex (unsigned char ch)
216 {
217 if (ch >= 10)
218 ch += 'a' - 10;
219 else
220 ch += '0';
221
222 return ch;
223 }
224
225 static inline void
num2hex(const void * p,std::size_t n,char * hex,bool swap_bytes)226 num2hex (const void *p, std::size_t n, char *hex, bool swap_bytes)
227 {
228 const unsigned char *cp = reinterpret_cast<const unsigned char *> (p);
229
230 std::size_t k = 0;
231
232 for (std::size_t i = 0; i < n; i++)
233 {
234 std::size_t j = (swap_bytes ? n - i - 1 : i);
235
236 unsigned char ch = cp[j];
237
238 hex[k++] = nibble2hex ((ch >> 4) & 0xF);
239 hex[k++] = nibble2hex (ch & 0xF);
240 }
241 }
242
243 template <typename T>
244 Cell
num2hex(const Array<T> & v,bool swap_bytes)245 num2hex (const Array<T>& v, bool swap_bytes)
246 {
247 const std::size_t nbytes = sizeof (T);
248 const std::size_t nchars = 2 * nbytes;
249
250 octave_idx_type nel = v.numel ();
251
252 string_vector sv (nel);
253
254 const T *pv = v.fortran_vec ();
255
256 for (octave_idx_type i = 0; i < nel; i++)
257 {
258 char hex[nchars];
259
260 num2hex (pv++, nbytes, hex, swap_bytes);
261
262 sv[i] = std::string (hex, nchars);
263 }
264
265 return Cell (v.dims (), sv);
266 }
267
268 DEFUN (num2hex, args, ,
269 doc: /* -*- texinfo -*-
270 @deftypefn {} {@var{s} =} num2hex (@var{n})
271 @deftypefnx {} {@var{s} =} num2hex (@var{n}, "cell")
272 Convert a numeric array to an array of hexadecimal strings.
273
274 For example:
275
276 @example
277 @group
278 num2hex ([-1, 1, e, Inf])
279 @result{} "bff0000000000000
280 3ff0000000000000
281 4005bf0a8b145769
282 7ff0000000000000"
283 @end group
284 @end example
285
286 If the argument @var{n} is a single precision number or vector, the returned
287 string has a length of 8. For example:
288
289 @example
290 @group
291 num2hex (single ([-1, 1, e, Inf]))
292 @result{} "bf800000
293 3f800000
294 402df854
295 7f800000"
296 @end group
297 @end example
298
299 With the optional second argument @qcode{"cell"}, return a cell array of
300 strings instead of a character array.
301 @seealso{hex2num, hex2dec, dec2hex}
302 @end deftypefn */)
303 {
304 int nargin = args.length ();
305
306 if (nargin < 1 || nargin > 2)
307 print_usage ();
308
309 bool as_cell = false;
310
311 if (nargin == 2)
312 {
313 std::string opt = args(1).xstring_value ("num2hex: second argument must be a string");
314 if (opt == "cell")
315 as_cell = true;
316 else
317 error ("num2hex: unrecognized option '%s'", opt.c_str ());
318 }
319
320 octave_value val = args(0);
321
322 if (val.iscomplex ())
323 error ("num2hex: N must be real");
324
325 Cell result;
326
327 // We always use big-endian order for hex digits.
328 bool is_float = val.is_single_type () || val.is_double_type ();
329 bool swap_bytes = is_little_endian (is_float);
330
331 if (val.is_int8_type ())
332 result = num2hex (val.int8_array_value (), swap_bytes);
333 else if (val.is_int16_type ())
334 result = num2hex<octave_int16> (val.int16_array_value (), swap_bytes);
335 else if (val.is_int32_type ())
336 result = num2hex<octave_int32> (val.int32_array_value (), swap_bytes);
337 else if (val.is_int64_type ())
338 result = num2hex<octave_int64> (val.int64_array_value (), swap_bytes);
339 else if (val.is_uint8_type ())
340 result = num2hex<octave_uint8> (val.uint8_array_value (), swap_bytes);
341 else if (val.is_uint16_type ())
342 result = num2hex<octave_uint16> (val.uint16_array_value (), swap_bytes);
343 else if (val.is_uint32_type ())
344 result = num2hex<octave_uint32> (val.uint32_array_value (), swap_bytes);
345 else if (val.is_uint64_type ())
346 result = num2hex<octave_uint64> (val.uint64_array_value (), swap_bytes);
347 else if (val.is_char_matrix ())
348 result = num2hex<char> (val.char_array_value (), swap_bytes);
349 else if (val.is_single_type ())
350 result = num2hex<float> (val.float_vector_value (), swap_bytes);
351 else if (val.is_double_type ())
352 result = num2hex<double> (val.vector_value (), swap_bytes);
353 else
354 err_wrong_type_arg ("num2hex", val);
355
356 return (as_cell
357 ? octave_value (result)
358 : octave_value (result.string_vector_value ()));
359 }
360
361 /*
362 %!assert (num2hex (-2:2), ["c000000000000000";"bff0000000000000";"0000000000000000";"3ff0000000000000";"4000000000000000"])
363 %!assert (num2hex (single (-2:2)), ["c0000000";"bf800000";"00000000";"3f800000";"40000000"])
364 %!assert (num2hex (intmax ("uint8")), "ff")
365 %!assert (num2hex (intmax ("uint16")), "ffff")
366 %!assert (num2hex (intmax ("uint32")), "ffffffff")
367 %!assert (num2hex (intmax ("uint32")), "ffffffff")
368 %!assert (num2hex (intmax ("uint64")), "ffffffffffffffff")
369
370 %!assert (hex2num (num2hex (pi)), pi)
371 %!assert (hex2num (num2hex (single (pi)), "single"), single (pi))
372
373 %!error num2hex ()
374 %!error num2hex (1,2)
375 %!error num2hex (1,"foo")
376 %!error num2hex (1,2,3)
377 %!error num2hex (1j)
378 */
379