libdap Updated for version 3.20.10
libdap4 is an implementation of OPeNDAP's DAP protocol.
D4StreamUnMarshaller.cc
1// D4StreamUnMarshaller.cc
2
3// -*- mode: c++; c-basic-offset:4 -*-
4
5// This file is part of libdap, A C++ implementation of the OPeNDAP Data
6// Access Protocol.
7
8// Copyright (c) 2012 OPeNDAP, Inc.
9// Author: James Gallagher <jgallagher@opendap.org>
10//
11// This library is free software; you can redistribute it and/or
12// modify it under the terms of the GNU Lesser General Public
13// License as published by the Free Software Foundation; either
14// version 2.1 of the License, or (at your option) any later version.
15//
16// This library is distributed in the hope that it will be useful,
17// but WITHOUT ANY WARRANTY; without even the implied warranty of
18// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19// Lesser General Public License for more details.
20//
21// You should have received a copy of the GNU Lesser General Public
22// License along with this library; if not, write to the Free Software
23// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24//
25// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.
26
27#include "config.h"
28
29#include <byteswap.h>
30#include <cassert>
31
32#include <iostream>
33#include <iomanip>
34#include <limits>
35#include <string>
36#include <sstream>
37
38//#define DODS_DEBUG2 1
39//#define DODS_DEBUG 1
40
41#include "util.h"
42#include "InternalErr.h"
43#include "D4StreamUnMarshaller.h"
44#include "debug.h"
45#include "DapIndent.h"
46
47namespace libdap {
48
59D4StreamUnMarshaller::D4StreamUnMarshaller(istream &in, bool twiddle_bytes) : d_in( in ), d_twiddle_bytes(twiddle_bytes)
60{
61 assert(sizeof(std::streamsize) >= sizeof(int64_t));
62
63#if USE_XDR_FOR_IEEE754_ENCODING
64 // XDR is used to handle transforming non-ieee754 reals, nothing else.
65 xdrmem_create(&d_source, d_buf, sizeof(dods_float64), XDR_DECODE);
66#endif
67
68 // This will cause exceptions to be thrown on i/o errors. The exception
69 // will be ostream::failure
70 d_in.exceptions(istream::failbit | istream::badbit);
71
72}
73
80D4StreamUnMarshaller::D4StreamUnMarshaller(istream &in) : d_in( in ), d_twiddle_bytes(false)
81{
82 assert(sizeof(std::streamsize) >= sizeof(int64_t));
83
84#if USE_XDR_FOR_IEEE754_ENCODING
85 // XDR is used to handle transforming non-ieee754 reals, nothing else.
86 xdrmem_create(&d_source, d_buf, sizeof(dods_float64), XDR_DECODE);
87#endif
88
89 // This will cause exceptions to be thrown on i/o errors. The exception
90 // will be ostream::failure
91 d_in.exceptions(istream::failbit | istream::badbit);
92}
93
94D4StreamUnMarshaller::~D4StreamUnMarshaller( )
95{
96#if USE_XDR_FOR_IEEE754_ENCODING
97 xdr_destroy(&d_source);
98#endif
99}
100
101Crc32::checksum D4StreamUnMarshaller::get_checksum()
102{
103 Crc32::checksum c;
104 d_in.read(reinterpret_cast<char*>(&c), sizeof(Crc32::checksum));
105
106 return c;
107}
108
109string D4StreamUnMarshaller::get_checksum_str()
110{
111 ostringstream oss;
112 oss.setf(ios::hex, ios::basefield);
113 oss << setfill('0') << setw(8) << get_checksum();
114
115 return oss.str();
116}
117
118void
119D4StreamUnMarshaller::get_byte( dods_byte &val )
120{
121 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_byte));
122}
123
124void
125D4StreamUnMarshaller::get_int8( dods_int8 &val )
126{
127 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_int8));
128}
129
130void
131D4StreamUnMarshaller::get_int16( dods_int16 &val )
132{
133 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_int16));
134 if (d_twiddle_bytes)
135 val = bswap_16(val);
136}
137
138void
139D4StreamUnMarshaller::get_int32( dods_int32 &val )
140{
141 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_int32));
142 if (d_twiddle_bytes)
143 val = bswap_32(val);
144}
145
146void
147D4StreamUnMarshaller::get_int64( dods_int64 &val )
148{
149 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_int64));
150 if (d_twiddle_bytes)
151 val = bswap_64(val);
152}
153
154void
155D4StreamUnMarshaller::get_float32( dods_float32 &val )
156{
157#if !USE_XDR_FOR_IEEE754_ENCODING
158 assert(std::numeric_limits<float>::is_iec559);
159
160 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_float32));
161 if (d_twiddle_bytes) {
162 dods_int32 *i = reinterpret_cast<dods_int32*>(&val);
163 *i = bswap_32(*i);
164 }
165
166#else
167 if (std::numeric_limits<float>::is_iec559) {
168 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_float32));
169 if (d_twiddle_bytes) {
170 dods_int32 *i = reinterpret_cast<dods_int32*>(&val);
171 *i = bswap_32(*i);
172 }
173
174 }
175 else {
176 xdr_setpos( &d_source, 0);
177 d_in.read(d_buf, sizeof(dods_float32));
178
179 if (!xdr_float(&d_source, &val))
180 throw Error("Network I/O Error. Could not read float 64 data.");
181 }
182#endif
183}
184
185void
186D4StreamUnMarshaller::get_float64( dods_float64 &val )
187{
188#if !USE_XDR_FOR_IEEE754_ENCODING
189 assert(std::numeric_limits<double>::is_iec559);
190
191 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_float64));
192 if (d_twiddle_bytes) {
193 dods_int64 *i = reinterpret_cast<dods_int64*>(&val);
194 *i = bswap_64(*i);
195 }
196
197#else
198 if (std::numeric_limits<float>::is_iec559) {
199 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_float64));
200 if (d_twiddle_bytes) {
201 dods_int64 *i = reinterpret_cast<dods_int64*>(&val);
202 *i = bswap_64(*i);
203 }
204 }
205 else {
206 xdr_setpos( &d_source, 0);
207 d_in.read(d_buf, sizeof(dods_float64));
208
209 if (!xdr_double(&d_source, &val))
210 throw Error("Network I/O Error. Could not read float 64 data.");
211 }
212#endif
213}
214
215void
216D4StreamUnMarshaller::get_uint16( dods_uint16 &val )
217{
218 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_uint16));
219 if (d_twiddle_bytes)
220 val = bswap_16(val);
221}
222
223void
224D4StreamUnMarshaller::get_uint32( dods_uint32 &val )
225{
226 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_uint32));
227 if (d_twiddle_bytes)
228 val = bswap_32(val);
229}
230
231void
232D4StreamUnMarshaller::get_uint64( dods_uint64 &val )
233{
234 d_in.read(reinterpret_cast<char*>(&val), sizeof(dods_uint64));
235 if (d_twiddle_bytes)
236 val = bswap_64(val);
237}
238
239void
240D4StreamUnMarshaller::get_str( string &val )
241{
242 int64_t len;
243 d_in.read(reinterpret_cast<char*>(&len), sizeof(int64_t));
244
245 val.resize(len);
246 d_in.read(&val[0], len);
247}
248
249void
250D4StreamUnMarshaller::get_url( string &val )
251{
252 get_str( val ) ;
253}
254
263int64_t
265{
266 int64_t count;
267 d_in.read(reinterpret_cast<char*>(&count), sizeof(count));
268 return count;
269}
270
278void
279D4StreamUnMarshaller::get_opaque_dap4( char **val, int64_t &len )
280{
281 //len = get_length_prefix();
282 d_in.read(reinterpret_cast<char*>(&len), sizeof(len));
283
284 *val = new char[len];
285 d_in.read(*val, len);
286}
287
288void
289D4StreamUnMarshaller::get_opaque_dap4( vector<uint8_t> &val )
290{
291 //len = get_length_prefix();
292 int64_t len;
293 d_in.read(reinterpret_cast<char*>(&len), sizeof(len));
294
295 val.resize(len);
296 d_in.read(reinterpret_cast<char*>(val.data()), len);
297}
298
299void
300D4StreamUnMarshaller::get_vector( char *val, int64_t bytes )
301{
302 d_in.read(val, bytes);
303}
304
305#if USE_XDR_FOR_IEEE754_ENCODING
306void D4StreamUnMarshaller::m_deserialize_reals(char *val, int64_t num, int width, Type type)
307{
308 int64_t size = num * width;
309 // char *buf = (char*)malloc(size); jhrg 7/23/13
310 vector<char> buf(size);
311 XDR xdr;
312 xdrmem_create(&xdr, buf.data(), size, XDR_DECODE);
313 try {
314 xdr_setpos(&d_source, 0);
315 d_in.read(buf.data(), size);
316
317 if(!xdr_array(&xdr, &val, (unsigned int *)&num, size, width, XDRUtils::xdr_coder(type)))
318 throw InternalErr(__FILE__, __LINE__, "Error deserializing a Float64 array");
319
320 if (xdr_getpos(&xdr) != size)
321 throw InternalErr(__FILE__, __LINE__, "Error deserializing a Float64 array");
322 }
323 catch (...) {
324 xdr_destroy(&xdr);
325 throw;
326 }
327 xdr_destroy(&xdr);
328}
329#endif
330
331void D4StreamUnMarshaller::m_twidle_vector_elements(char *vals, int64_t num, int width)
332{
333 switch (width) {
334 case 2: {
335 dods_int16 *local = reinterpret_cast<dods_int16*>(vals);
336 while (num--) {
337 *local = bswap_16(*local);
338 local++;
339 }
340 break;
341 }
342 case 4: {
343 dods_int32 *local = reinterpret_cast<dods_int32*>(vals);;
344 while (num--) {
345 *local = bswap_32(*local);
346 local++;
347 }
348 break;
349 }
350 case 8: {
351 dods_int64 *local = reinterpret_cast<dods_int64*>(vals);;
352 while (num--) {
353 *local = bswap_64(*local);
354 local++;
355 }
356 break;
357 }
358 default:
359 throw InternalErr(__FILE__, __LINE__, "Unrecognized word size.");
360 }
361}
362
363void
364D4StreamUnMarshaller::get_vector(char *val, int64_t num_elem, int elem_size)
365{
366 assert(std::numeric_limits<float>::is_iec559);
367 assert(std::numeric_limits<double>::is_iec559);
368 assert(val);
369 assert(num_elem >= 0);
370 assert(elem_size > 0);
371
372 int64_t bytes;
373
374 switch (elem_size) {
375 case 1:
376 assert(!"Don't call this method for bytes, use put_vector(val, bytes) instead");
377 bytes = num_elem;
378 break;
379 case 2:
380 // Don't bother testing the sign bit
381 assert(!(num_elem & 0x4000000000000000)); // 0x 40 00 --> 0100 0000
382 bytes = num_elem << 1;
383 break;
384 case 4:
385 assert(!(num_elem & 0x6000000000000000)); // 0x 60 00 --> 0110 0000
386 bytes = num_elem << 2;
387 break;
388 case 8:
389 assert(!(num_elem & 0x7000000000000000)); // 0111 0000
390 bytes = num_elem << 3;
391 break;
392 default:
393 bytes = num_elem * elem_size;
394 break;
395 }
396
397 d_in.read(val, bytes);
398
399 if (d_twiddle_bytes)
400 m_twidle_vector_elements(val, num_elem, elem_size);
401}
402
403void
404D4StreamUnMarshaller::get_vector_float32(char *val, int64_t num_elem)
405{
406#if !USE_XDR_FOR_IEEE754_ENCODING
407 assert(std::numeric_limits<float>::is_iec559);
408 assert(val);
409 assert(num_elem >= 0);
410 assert(!(num_elem & 0x6000000000000000)); // 0x 60 00 --> 0110 0000
411
412 int64_t bytes = num_elem << 2;
413
414 d_in.read(val, bytes);
415
416 if (d_twiddle_bytes)
417 m_twidle_vector_elements(val, num_elem, sizeof(dods_float32));
418
419#else
420 if (type == dods_float32_c && !std::numeric_limits<float>::is_iec559) {
421 // If not using IEEE 754, use XDR to get it that way.
422 m_deserialize_reals(val, num, 4, type);
423 }
424 else if (type == dods_float64_c && !std::numeric_limits<double>::is_iec559) {
425 m_deserialize_reals(val, num, 8, type);
426 }
427 else {
428 d_in.read(val, num * width);
429 if (d_twiddle_bytes)
430 m_twidle_vector_elements(val, num, width);
431 }
432#endif
433}
434
435void
436D4StreamUnMarshaller::get_vector_float64(char *val, int64_t num_elem)
437{
438#if !USE_XDR_FOR_IEEE754_ENCODING
439 assert(std::numeric_limits<float>::is_iec559);
440 assert(val);
441 assert(num_elem >= 0);
442 assert(!(num_elem & 0x7000000000000000)); // 0x 70 00 --> 0111 0000
443
444 int64_t bytes = num_elem << 3;
445
446 d_in.read(val, bytes);
447
448 if (d_twiddle_bytes)
449 m_twidle_vector_elements(val, num_elem, sizeof(dods_float64));
450
451#else
452 if (type == dods_float32_c && !std::numeric_limits<float>::is_iec559) {
453 // If not using IEEE 754, use XDR to get it that way.
454 m_deserialize_reals(val, num, 4, type);
455 }
456 else if (type == dods_float64_c && !std::numeric_limits<double>::is_iec559) {
457 m_deserialize_reals(val, num, 8, type);
458 }
459 else {
460 d_in.read(val, num * width);
461 if (d_twiddle_bytes)
462 m_twidle_vector_elements(val, num, width);
463 }
464#endif
465}
466
467void
468D4StreamUnMarshaller::dump(ostream &strm) const
469{
470 strm << DapIndent::LMarg << "D4StreamUnMarshaller::dump - ("
471 << (void *)this << ")" << endl ;
472}
473
474} // namespace libdap
475
virtual void get_opaque_dap4(char **val, int64_t &len)
virtual void dump(ostream &strm) const
dump the contents of this object to the specified ostream
static xdrproc_t xdr_coder(const Type &t)
Returns a function used to encode elements of an array.
Definition XDRUtils.cc:145
top level DAP object to house generic methods