rdesktop/trunk/rdpsnd_dsp.c

/*
   rdesktop: A Remote Desktop Protocol client.
   Sound DSP routines
   Copyright (C) Michael Gernoth 2006

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <strings.h>

#include "rdesktop.h"
#include "rdpsnd.h"
#include "rdpsnd_dsp.h"

#ifdef HAVE_LIBSAMPLERATE
#include <samplerate.h>

#define SRC_CONVERTER SRC_SINC_MEDIUM_QUALITY
#endif

#define MAX_VOLUME 65535

static uint16 softvol_left = MAX_VOLUME;
static uint16 softvol_right = MAX_VOLUME;
static uint32 resample_to_srate = 44100;
static uint16 resample_to_bitspersample = 16;
static uint16 resample_to_channels = 2;
#ifdef HAVE_LIBSAMPLERATE
static SRC_STATE *src_converter = NULL;
#endif

void
rdpsnd_dsp_softvol_set(uint16 left, uint16 right)
{
        softvol_left = left;
        softvol_right = right;
        DEBUG(("rdpsnd_dsp_softvol_set: left: %u, right: %u\n", left, right));
}

void
rdpsnd_dsp_softvol(unsigned char *buffer, unsigned int size, WAVEFORMATEX * format)
{
        unsigned int factor_left, factor_right;
        unsigned char *posin = buffer;
        unsigned char *posout = buffer;

        if ((softvol_left == MAX_VOLUME) && (softvol_right == MAX_VOLUME))
                return;

        factor_left = (softvol_left * 256) / MAX_VOLUME;
        factor_right = (softvol_right * 256) / MAX_VOLUME;

        if (format->nChannels == 1)
        {
                factor_left = factor_right = (factor_left + factor_right) / 2;
        }

        if (format->wBitsPerSample == 8)
        {
                sint8 val;

                while (posout < buffer + size)
                {
                        /* Left */
                        val = *posin++;
                        val = (val * factor_left) >> 8;
                        *posout++ = val;

                        /* Right */
                        val = *posin++;
                        val = (val * factor_right) >> 8;
                        *posout++ = val;
                }
        }
        else
        {
                sint16 val;

                while (posout < buffer + size)
                {
                        /* Left */
                        val = *posin++;
                        val |= *posin++ << 8;
                        val = (val * factor_left) >> 8;
                        *posout++ = val & 0xff;
                        *posout++ = val >> 8;

                        /* Right */
                        val = *posin++;
                        val |= *posin++ << 8;
                        val = (val * factor_right) >> 8;
                        *posout++ = val & 0xff;
                        *posout++ = val >> 8;
                }
        }

        DEBUG(("using softvol with factors left: %d, right: %d (%d/%d)\n", factor_left,
               factor_right, format->wBitsPerSample, format->nChannels));
}

void
rdpsnd_dsp_swapbytes(unsigned char *buffer, unsigned int size, WAVEFORMATEX * format)
{
        int i;
        uint8 swap;

        if (format->wBitsPerSample == 8)
                return;

        for (i = 0; i < size; i += 2)
        {
                swap = *(buffer + i);
                *(buffer + i) = *(buffer + i + 1);
                *(buffer + i + 1) = swap;
        }
}

BOOL
rdpsnd_dsp_resample_set(uint32 device_srate, uint16 device_bitspersample, uint16 device_channels)
{
#ifdef HAVE_LIBSAMPLERATE
        int err;
#endif

        if (device_bitspersample != 16 && device_bitspersample != 8)
                return False;

        if (device_channels != 1 && device_channels != 2)
                return False;

        resample_to_srate = device_srate;
        resample_to_bitspersample = device_bitspersample;
        resample_to_channels = device_channels;

#ifdef HAVE_LIBSAMPLERATE
        if (src_converter != NULL)
                src_converter = src_delete(src_converter);

        if ((src_converter = src_new(SRC_CONVERTER, device_channels, &err)) == NULL)
        {
                warning("src_new failed: %d!\n", err);
                return False;
        }
#endif

        return True;
}

BOOL
rdpsnd_dsp_resample_supported(WAVEFORMATEX * format)
{
        if (format->wFormatTag != WAVE_FORMAT_PCM)
                return False;
        if ((format->nChannels != 1) && (format->nChannels != 2))
                return False;
        if ((format->wBitsPerSample != 8) && (format->wBitsPerSample != 16))
                return False;

        return True;
}

uint32
rdpsnd_dsp_resample(unsigned char **out, unsigned char *in, unsigned int size,
                    WAVEFORMATEX * format, BOOL stream_be)
{
#ifdef HAVE_LIBSAMPLERATE
        SRC_DATA resample_data;
        float *infloat, *outfloat;
        int err;
#else
        int ratio1k = (resample_to_srate * 1000) / format->nSamplesPerSec;
#endif
        int innum, outnum;
        unsigned char *tmpdata = NULL, *tmp = NULL;
        int samplewidth = format->wBitsPerSample / 8;
        int outsize = 0;
        int i;

        if ((resample_to_bitspersample == format->wBitsPerSample) &&
            (resample_to_channels == format->nChannels) &&
            (resample_to_srate == format->nSamplesPerSec))
                return 0;

#ifdef B_ENDIAN
        if (!stream_be)
                rdpsnd_dsp_swapbytes(in, size, format);
#endif

        if (resample_to_channels != format->nChannels)
        {
                int newsize = (size / format->nChannels) * resample_to_channels;
                tmpdata = xmalloc(newsize);

                for (i = 0; i < newsize / samplewidth; i++)
                {
                        if (format->nChannels > resample_to_channels)
                                memcpy(tmpdata + (i * samplewidth),
                                       in +
                                       (((i * format->nChannels) / resample_to_channels) *
                                        samplewidth), samplewidth);
                        else
                                memcpy(tmpdata + (i * samplewidth),
                                       in +
                                       (((i / resample_to_channels) * format->nChannels +
                                         (i % format->nChannels)) * samplewidth), samplewidth);

                }

                in = tmpdata;
                size = newsize;
        }


        /* Expand 8bit input-samples to 16bit */
#ifndef HAVE_LIBSAMPLERATE      /* libsamplerate needs 16bit samples */
        if (format->wBitsPerSample != resample_to_bitspersample)
#endif
        {
                /* source: 8 bit, dest: 16bit */
                if (format->wBitsPerSample == 8)
                {
                        tmp = tmpdata;
                        tmpdata = xmalloc(size * 2);
                        for (i = 0; i < size; i++)
                        {
                                tmpdata[i * 2] = in[i];
                                tmpdata[(i * 2) + 1] = 0x00;
                        }
                        in = tmpdata;
                        samplewidth = 16 / 2;
                        size *= 2;

                        if (tmp != NULL)
                                xfree(tmp);
                }
        }

        innum = size / samplewidth;

        /* Do the resampling */
#ifdef HAVE_LIBSAMPLERATE
        if (src_converter == NULL)
        {
                warning("no samplerate converter available!!\n");
                return 0;
        }

        outnum = ((float) innum * ((float) resample_to_srate / (float) format->nSamplesPerSec)) + 1;

        infloat = xmalloc(sizeof(float) * innum);
        outfloat = xmalloc(sizeof(float) * outnum);

        src_short_to_float_array((short *) in, infloat, innum);

        bzero(&resample_data, sizeof(resample_data));
        resample_data.data_in = infloat;
        resample_data.data_out = outfloat;
        resample_data.input_frames = innum / resample_to_channels;
        resample_data.output_frames = outnum / resample_to_channels;
        resample_data.src_ratio = (double) resample_to_srate / (double) format->nSamplesPerSec;
        resample_data.end_of_input = 0;

        if ((err = src_process(src_converter, &resample_data)) != 0)
                error("src_process: %s", src_strerror(err));

        xfree(infloat);

        outsize = resample_data.output_frames_gen * resample_to_channels * samplewidth;
        *out = xmalloc(outsize);
        src_float_to_short_array(outfloat, (short *) *out,
                                 resample_data.output_frames_gen * resample_to_channels);
        xfree(outfloat);

#else
        /* Michaels simple linear resampler */
        if (resample_to_srate < format->nSamplesPerSec)
        {
                warning("downsampling currently not supported!\n");
                return 0;
        }

        outnum = (innum * ratio1k) / 1000;

        outsize = outnum * samplewidth;
        *out = xmalloc(outsize);
        bzero(*out, outsize);

        for (i = 0; i < outsize / (resample_to_channels * samplewidth); i++)
        {
                int source = (i * 1000) / ratio1k;
                int j;

                if (source * resample_to_channels + samplewidth > size)
                        break;

                for (j = 0; j < resample_to_channels; j++)
                {
                        memcpy(*out + (i * resample_to_channels * samplewidth) + (samplewidth * j),
                               in + (source * resample_to_channels * samplewidth) +
                               (samplewidth * j), samplewidth);
                }
        }
        outsize = i * resample_to_channels * samplewidth;
#endif

        if (tmpdata != NULL)
                xfree(tmpdata);

        /* Shrink 16bit output-samples to 8bit */
#ifndef HAVE_LIBSAMPLERATE      /* libsamplerate produces 16bit samples */
        if (format->wBitsPerSample != resample_to_bitspersample)
#endif
        {
                /* source: 16 bit, dest: 8 bit */
                if (resample_to_bitspersample == 8)
                {
                        for (i = 0; i < outsize; i++)
                        {
                                *out[i] = *out[i * 2];
                        }
                        outsize /= 2;
                }
        }

#ifdef B_ENDIAN
        if (!stream_be)
                rdpsnd_dsp_swapbytes(*out, outsize, format);
#endif
        return outsize;
}

STREAM
rdpsnd_dsp_process(STREAM s, struct audio_driver * current_driver, WAVEFORMATEX * format)
{
        static struct stream out;
        BOOL stream_be = False;

        /* softvol and byteswap do not change the amount of data they
           return, so they can operate on the input-stream */
        if (current_driver->wave_out_volume == rdpsnd_dsp_softvol_set)
                rdpsnd_dsp_softvol(s->data, s->size, format);

#ifdef B_ENDIAN
        if (current_driver->need_byteswap_on_be)
        {
                rdpsnd_dsp_swapbytes(s->data, s->size, format);
                stream_be = True;
        }
#endif

        out.data = NULL;

        if (current_driver->need_resampling)
                out.size = rdpsnd_dsp_resample(&out.data, s->data, s->size, format, stream_be);

        if (out.data == NULL)
        {
                out.data = xmalloc(s->size);
                memcpy(out.data, s->data, s->size);
                out.size = s->size;
        }

        out.p = out.data;
        out.end = out.p + out.size;

        return &out;
}
1	stargo	1258	/*
2			rdesktop: A Remote Desktop Protocol client.
3			Sound DSP routines
4			Copyright (C) Michael Gernoth 2006
5
6			This program is free software; you can redistribute it and/or modify
7			it under the terms of the GNU General Public License as published by
8			the Free Software Foundation; either version 2 of the License, or
9			(at your option) any later version.
10
11			This program is distributed in the hope that it will be useful,
12			but WITHOUT ANY WARRANTY; without even the implied warranty of
13			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			GNU General Public License for more details.
15
16			You should have received a copy of the GNU General Public License
17			along with this program; if not, write to the Free Software
18			Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19			*/
20
21	stargo	1285	#include <strings.h>
22
23	stargo	1258	#include "rdesktop.h"
24			#include "rdpsnd.h"
25			#include "rdpsnd_dsp.h"
26
27	stargo	1278	#ifdef HAVE_LIBSAMPLERATE
28			#include <samplerate.h>
29
30			#define SRC_CONVERTER SRC_SINC_MEDIUM_QUALITY
31			#endif
32
33	stargo	1258	#define MAX_VOLUME 65535
34
35			static uint16 softvol_left = MAX_VOLUME;
36			static uint16 softvol_right = MAX_VOLUME;
37	stargo	1276	static uint32 resample_to_srate = 44100;
38			static uint16 resample_to_bitspersample = 16;
39			static uint16 resample_to_channels = 2;
40	stargo	1278	#ifdef HAVE_LIBSAMPLERATE
41			static SRC_STATE *src_converter = NULL;
42			#endif
43	stargo	1258
44			void
45			rdpsnd_dsp_softvol_set(uint16 left, uint16 right)
46			{
47			softvol_left = left;
48			softvol_right = right;
49			DEBUG(("rdpsnd_dsp_softvol_set: left: %u, right: %u\n", left, right));
50			}
51
52	stargo	1260	void
53	stargo	1259	rdpsnd_dsp_softvol(unsigned char buffer, unsigned int size, WAVEFORMATEX format)
54	stargo	1258	{
55			unsigned int factor_left, factor_right;
56	stargo	1259	unsigned char *posin = buffer;
57			unsigned char *posout = buffer;
58	stargo	1258
59	stargo	1259	if ((softvol_left == MAX_VOLUME) && (softvol_right == MAX_VOLUME))
60			return;
61
62	stargo	1270	factor_left = (softvol_left * 256) / MAX_VOLUME;
63			factor_right = (softvol_right * 256) / MAX_VOLUME;
64	stargo	1258
65			if (format->nChannels == 1)
66			{
67			factor_left = factor_right = (factor_left + factor_right) / 2;
68			}
69
70			if (format->wBitsPerSample == 8)
71			{
72	stargo	1262	sint8 val;
73	stargo	1258
74	stargo	1259	while (posout < buffer + size)
75	stargo	1258	{
76			/* Left */
77			val = *posin++;
78			val = (val * factor_left) >> 8;
79			*posout++ = val;
80
81			/* Right */
82			val = *posin++;
83			val = (val * factor_right) >> 8;
84			*posout++ = val;
85			}
86			}
87			else
88			{
89	stargo	1262	sint16 val;
90	stargo	1258
91	stargo	1259	while (posout < buffer + size)
92	stargo	1258	{
93			/* Left */
94			val = *posin++;
95			val \|= *posin++ << 8;
96			val = (val * factor_left) >> 8;
97			*posout++ = val & 0xff;
98			*posout++ = val >> 8;
99
100			/* Right */
101			val = *posin++;
102			val \|= *posin++ << 8;
103			val = (val * factor_right) >> 8;
104			*posout++ = val & 0xff;
105			*posout++ = val >> 8;
106			}
107			}
108
109	stargo	1263	DEBUG(("using softvol with factors left: %d, right: %d (%d/%d)\n", factor_left,
110			factor_right, format->wBitsPerSample, format->nChannels));
111	stargo	1258	}
112
113	stargo	1260	void
114			rdpsnd_dsp_swapbytes(unsigned char buffer, unsigned int size, WAVEFORMATEX format)
115			{
116			int i;
117			uint8 swap;
118
119			if (format->wBitsPerSample == 8)
120			return;
121
122			for (i = 0; i < size; i += 2)
123			{
124			swap = *(buffer + i);
125			(buffer + i) = (buffer + i + 1);
126			*(buffer + i + 1) = swap;
127			}
128			}
129
130	stargo	1276	BOOL
131			rdpsnd_dsp_resample_set(uint32 device_srate, uint16 device_bitspersample, uint16 device_channels)
132			{
133	stargo	1278	#ifdef HAVE_LIBSAMPLERATE
134			int err;
135			#endif
136
137	stargo	1276	if (device_bitspersample != 16 && device_bitspersample != 8)
138			return False;
139
140			if (device_channels != 1 && device_channels != 2)
141			return False;
142
143			resample_to_srate = device_srate;
144			resample_to_bitspersample = device_bitspersample;
145			resample_to_channels = device_channels;
146
147	stargo	1278	#ifdef HAVE_LIBSAMPLERATE
148			if (src_converter != NULL)
149			src_converter = src_delete(src_converter);
150
151			if ((src_converter = src_new(SRC_CONVERTER, device_channels, &err)) == NULL)
152			{
153			warning("src_new failed: %d!\n", err);
154			return False;
155			}
156			#endif
157
158	stargo	1276	return True;
159			}
160
161			BOOL
162			rdpsnd_dsp_resample_supported(WAVEFORMATEX * format)
163			{
164			if (format->wFormatTag != WAVE_FORMAT_PCM)
165			return False;
166			if ((format->nChannels != 1) && (format->nChannels != 2))
167			return False;
168			if ((format->wBitsPerSample != 8) && (format->wBitsPerSample != 16))
169			return False;
170
171			return True;
172			}
173
174			uint32
175			rdpsnd_dsp_resample(unsigned char *out, unsigned char in, unsigned int size,
176	stargo	1278	WAVEFORMATEX * format, BOOL stream_be)
177	stargo	1276	{
178	stargo	1278	#ifdef HAVE_LIBSAMPLERATE
179			SRC_DATA resample_data;
180			float infloat, outfloat;
181	stargo	1282	int err;
182	stargo	1278	#else
183	stargo	1283	int ratio1k = (resample_to_srate * 1000) / format->nSamplesPerSec;
184	stargo	1278	#endif
185	stargo	1283	int innum, outnum;
186	stargo	1288	unsigned char tmpdata = NULL, tmp = NULL;
187	stargo	1276	int samplewidth = format->wBitsPerSample / 8;
188	stargo	1278	int outsize = 0;
189	stargo	1281	int i;
190	stargo	1276
191	stargo	1277	if ((resample_to_bitspersample == format->wBitsPerSample) &&
192			(resample_to_channels == format->nChannels) &&
193			(resample_to_srate == format->nSamplesPerSec))
194			return 0;
195
196	stargo	1278	#ifdef B_ENDIAN
197			if (!stream_be)
198	stargo	1281	rdpsnd_dsp_swapbytes(in, size, format);
199	stargo	1278	#endif
200	stargo	1281
201	stargo	1288	if (resample_to_channels != format->nChannels)
202			{
203			int newsize = (size / format->nChannels) * resample_to_channels;
204			tmpdata = xmalloc(newsize);
205
206			for (i = 0; i < newsize / samplewidth; i++)
207			{
208			if (format->nChannels > resample_to_channels)
209			memcpy(tmpdata + (i * samplewidth),
210			in +
211			(((i * format->nChannels) / resample_to_channels) *
212			samplewidth), samplewidth);
213			else
214			memcpy(tmpdata + (i * samplewidth),
215			in +
216			(((i / resample_to_channels) * format->nChannels +
217			(i % format->nChannels)) * samplewidth), samplewidth);
218
219			}
220
221			in = tmpdata;
222			size = newsize;
223			}
224
225
226	stargo	1281	/* Expand 8bit input-samples to 16bit */
227			#ifndef HAVE_LIBSAMPLERATE /* libsamplerate needs 16bit samples */
228			if (format->wBitsPerSample != resample_to_bitspersample)
229			#endif
230			{
231			/* source: 8 bit, dest: 16bit */
232			if (format->wBitsPerSample == 8)
233	stargo	1278	{
234	stargo	1288	tmp = tmpdata;
235	stargo	1281	tmpdata = xmalloc(size * 2);
236			for (i = 0; i < size; i++)
237			{
238			tmpdata[i * 2] = in[i];
239			tmpdata[(i * 2) + 1] = 0x00;
240			}
241			in = tmpdata;
242			samplewidth = 16 / 2;
243			size *= 2;
244	stargo	1288
245			if (tmp != NULL)
246			xfree(tmp);
247	stargo	1278	}
248	stargo	1281	}
249	stargo	1278
250	stargo	1283	innum = size / samplewidth;
251
252	stargo	1281	/* Do the resampling */
253	stargo	1278	#ifdef HAVE_LIBSAMPLERATE
254			if (src_converter == NULL)
255	stargo	1276	{
256	stargo	1278	warning("no samplerate converter available!!\n");
257			return 0;
258			}
259
260	stargo	1283	outnum = ((float) innum * ((float) resample_to_srate / (float) format->nSamplesPerSec)) + 1;
261	stargo	1278
262			infloat = xmalloc(sizeof(float) * innum);
263			outfloat = xmalloc(sizeof(float) * outnum);
264
265			src_short_to_float_array((short *) in, infloat, innum);
266
267			bzero(&resample_data, sizeof(resample_data));
268			resample_data.data_in = infloat;
269			resample_data.data_out = outfloat;
270			resample_data.input_frames = innum / resample_to_channels;
271			resample_data.output_frames = outnum / resample_to_channels;
272			resample_data.src_ratio = (double) resample_to_srate / (double) format->nSamplesPerSec;
273			resample_data.end_of_input = 0;
274
275	stargo	1282	if ((err = src_process(src_converter, &resample_data)) != 0)
276			error("src_process: %s", src_strerror(err));
277
278	stargo	1278	xfree(infloat);
279
280	stargo	1282	outsize = resample_data.output_frames_gen * resample_to_channels * samplewidth;
281	stargo	1278	*out = xmalloc(outsize);
282	stargo	1283	src_float_to_short_array(outfloat, (short ) out,
283			resample_data.output_frames_gen * resample_to_channels);
284	stargo	1278	xfree(outfloat);
285
286			#else
287	stargo	1283	/* Michaels simple linear resampler */
288			if (resample_to_srate < format->nSamplesPerSec)
289	stargo	1278	{
290	stargo	1283	warning("downsampling currently not supported!\n");
291	stargo	1276	return 0;
292			}
293
294	stargo	1283	outnum = (innum * ratio1k) / 1000;
295
296			outsize = outnum * samplewidth;
297	stargo	1277	*out = xmalloc(outsize);
298	stargo	1283	bzero(*out, outsize);
299	stargo	1277
300	stargo	1283	for (i = 0; i < outsize / (resample_to_channels * samplewidth); i++)
301	stargo	1276	{
302	stargo	1291	int source = (i * 1000) / ratio1k;
303	stargo	1287	int j;
304	stargo	1283
305			if (source * resample_to_channels + samplewidth > size)
306			break;
307
308	stargo	1287	for (j = 0; j < resample_to_channels; j++)
309	stargo	1283	{
310	stargo	1287	memcpy(out + (i resample_to_channels * samplewidth) + (samplewidth * j),
311	stargo	1288	in + (source * resample_to_channels * samplewidth) +
312			(samplewidth * j), samplewidth);
313	stargo	1283	}
314	stargo	1276	}
315	stargo	1283	outsize = i * resample_to_channels * samplewidth;
316	stargo	1278	#endif
317	stargo	1276
318	stargo	1281	if (tmpdata != NULL)
319			xfree(tmpdata);
320
321			/* Shrink 16bit output-samples to 8bit */
322			#ifndef HAVE_LIBSAMPLERATE /* libsamplerate produces 16bit samples */
323			if (format->wBitsPerSample != resample_to_bitspersample)
324			#endif
325			{
326			/* source: 16 bit, dest: 8 bit */
327			if (resample_to_bitspersample == 8)
328			{
329			for (i = 0; i < outsize; i++)
330			{
331			out[i] = out[i * 2];
332			}
333			outsize /= 2;
334			}
335			}
336
337	stargo	1278	#ifdef B_ENDIAN
338			if (!stream_be)
339	stargo	1281	rdpsnd_dsp_swapbytes(*out, outsize, format);
340	stargo	1278	#endif
341	stargo	1281	return outsize;
342	stargo	1276	}
343
344	stargo	1263	STREAM
345	stargo	1276	rdpsnd_dsp_process(STREAM s, struct audio_driver * current_driver, WAVEFORMATEX * format)
346	stargo	1258	{
347	stargo	1263	static struct stream out;
348	stargo	1278	BOOL stream_be = False;
349	stargo	1258
350	stargo	1263	/* softvol and byteswap do not change the amount of data they
351			return, so they can operate on the input-stream */
352	stargo	1258	if (current_driver->wave_out_volume == rdpsnd_dsp_softvol_set)
353	stargo	1263	rdpsnd_dsp_softvol(s->data, s->size, format);
354	stargo	1258
355	stargo	1260	#ifdef B_ENDIAN
356			if (current_driver->need_byteswap_on_be)
357	stargo	1278	{
358	stargo	1263	rdpsnd_dsp_swapbytes(s->data, s->size, format);
359	stargo	1278	stream_be = True;
360			}
361	stargo	1260	#endif
362
363	stargo	1276	out.data = NULL;
364	stargo	1263
365	stargo	1279	if (current_driver->need_resampling)
366	stargo	1278	out.size = rdpsnd_dsp_resample(&out.data, s->data, s->size, format, stream_be);
367	stargo	1263
368	stargo	1276	if (out.data == NULL)
369			{
370			out.data = xmalloc(s->size);
371			memcpy(out.data, s->data, s->size);
372			out.size = s->size;
373			}
374
375	stargo	1263	out.p = out.data;
376			out.end = out.p + out.size;
377
378			return &out;
379	stargo	1258	}