+/*
+ * recording function
+ * Records all data from down and from up into one single stream.
+ * Both streams may have gaps or jitter.
+ * A Jitter buffer for both streams is used to compensate jitter.
+ *
+ * If one stream (dir) received packets, they are stored to a
+ * buffer to wait for the other stream (dir), so both streams can
+ * be combined. If the buffer is full, it's content is written
+ * without mixing stream. (assuming only one stram (dir) exists.)
+ * A flag is used to indicate what stream is currently in buffer.
+ *
+ * NOTE: First stereo sample (odd) is from down, second is from up.
+ */
+void Port::record(unsigned char *data, int length, int dir_fromup)
+{
+ unsigned char write_buffer[1024], *d;
+ signed short *s;
+ int free, i, ii;
+ signed long sample;
+
+ /* no recording */
+ if (!p_record || !length)
+ return;
+
+ /* skip data from local caller (dtmf input) */
+ if (p_record_skip && !dir_fromup)
+ {
+ /* more to skip than we have */
+ if (p_record_skip > length)
+ {
+ p_record_skip -= length;
+ return;
+ }
+ /* less to skip */
+ data += p_record_skip;
+ length -= p_record_skip;
+ p_record_skip = 0;
+ }
+
+//printf("dir=%d len=%d\n", dir_fromup, length);
+
+ free = ((p_record_buffer_readp - p_record_buffer_writep - 1) & RECORD_BUFFER_MASK);
+
+//PDEBUG(DEBUG_PORT, "record(data,%d,%d): free=%d, p_record_buffer_dir=%d, p_record_buffer_readp=%d, p_record_buffer_writep=%d.\n", length, dir_fromup, free, p_record_buffer_dir, p_record_buffer_readp, p_record_buffer_writep);
+
+ /* the buffer stores the same data stream */
+ if (dir_fromup == p_record_buffer_dir)
+ {
+same_again:
+
+//printf("same free=%d length=%d\n", free, length);
+ /* first write what we can to the buffer */
+ while(free && length)
+ {
+ p_record_buffer[p_record_buffer_writep] = audio_law_to_s32[*data++];
+ p_record_buffer_writep = (p_record_buffer_writep + 1) & RECORD_BUFFER_MASK;
+ free--;
+ length--;
+ }
+ /* all written, so we return */
+ if (!length)
+ return;
+ /* still data left, buffer is full, so we need to write a chunk to file */
+ switch(p_record_type)
+ {
+ case CODEC_MONO:
+ s = (signed short *)write_buffer;
+ i = 0;
+ while(i < 256)
+ {
+ *s++ = p_record_buffer[p_record_buffer_readp];
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ i++;
+ }
+ fwrite(write_buffer, 512, 1, p_record);
+ p_record_length += 512;
+ break;
+
+ case CODEC_STEREO:
+ s = (signed short *)write_buffer;
+ if (p_record_buffer_dir)
+ {
+ i = 0;
+ while(i < 256)
+ {
+ *s++ = 0; /* nothing from down */
+ *s++ = p_record_buffer[p_record_buffer_readp];
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ i++;
+ }
+ } else
+ {
+ i = 0;
+ while(i < 256)
+ {
+ *s++ = p_record_buffer[p_record_buffer_readp];
+ *s++ = 0; /* nothing from up */
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ i++;
+ }
+ }
+ fwrite(write_buffer, 1024, 1, p_record);
+ p_record_length += 1024;
+ break;
+
+ case CODEC_8BIT:
+ d = write_buffer;
+ i = 0;
+ while(i < 256)
+ {
+ *d++ = ((unsigned short)(p_record_buffer[p_record_buffer_readp]+0x8000)) >> 8;
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ i++;
+ }
+ fwrite(write_buffer, 512, 1, p_record);
+ p_record_length += 512;
+ break;
+
+ case CODEC_LAW:
+ d = write_buffer;
+ i = 0;
+ while(i < 256)
+ {
+ *d++ = audio_s16_to_law[p_record_buffer[p_record_buffer_readp] & 0xffff];
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ i++;
+ }
+ fwrite(write_buffer, 256, 1, p_record);
+ p_record_length += 256;
+ break;
+ }
+ /* because we still have data, we write again */
+ free += 256;
+ goto same_again;
+ }
+ /* the buffer stores the other stream */
+
+different_again:
+ /* if buffer empty, change it */
+ if (p_record_buffer_readp == p_record_buffer_writep)
+ {
+ p_record_buffer_dir = dir_fromup;
+ goto same_again;
+ }
+ /* how much data can we mix ? */
+ ii = (p_record_buffer_writep - p_record_buffer_readp) & RECORD_BUFFER_MASK;
+ if (length < ii)
+ ii = length;
+
+ if (ii > 256)
+ ii = 256;
+//printf("same ii=%d length=%d\n", ii, length);
+//PDEBUG(DEBUG_PORT, "record(data,%d,%d): free=%d, p_record_buffer_dir=%d, p_record_buffer_readp=%d, p_record_buffer_writep=%d: mixing %d bytes.\n", length, dir_fromup, free, p_record_buffer_dir, p_record_buffer_readp, p_record_buffer_writep, ii);
+
+ /* write data mixed with the buffer */
+ switch(p_record_type)
+ {
+ case CODEC_MONO:
+ s = (signed short *)write_buffer;
+ i = 0;
+ while(i < ii)
+ {
+ sample = p_record_buffer[p_record_buffer_readp]
+ + audio_law_to_s32[*data++];
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ if (sample < SHORT_MIN) sample = SHORT_MIN;
+ if (sample > SHORT_MAX) sample = SHORT_MAX;
+ *s++ = sample;
+ i++;
+ }
+ fwrite(write_buffer, ii<<1, 1, p_record);
+ p_record_length += (ii<<1);
+ break;
+
+ case CODEC_STEREO:
+ s = (signed short *)write_buffer;
+ if (p_record_buffer_dir)
+ {
+ i = 0;
+ while(i < ii)
+ {
+ *s++ = audio_law_to_s32[*data++];
+ *s++ = p_record_buffer[p_record_buffer_readp];
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ i++;
+ }
+ } else
+ {
+ i = 0;
+ while(i < ii)
+ {
+ *s++ = p_record_buffer[p_record_buffer_readp];
+ *s++ = audio_law_to_s32[*data++];
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ i++;
+ }
+ }
+ fwrite(write_buffer, ii<<2, 1, p_record);
+ p_record_length += (ii<<2);
+ break;
+
+ case CODEC_8BIT:
+ d = write_buffer;
+ i = 0;
+ while(i < ii)
+ {
+ sample = p_record_buffer[p_record_buffer_readp]
+ + audio_law_to_s32[*data++];
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ if (sample < SHORT_MIN) sample = SHORT_MIN;
+ if (sample > SHORT_MAX) sample = SHORT_MAX;
+ *d++ = (sample+0x8000) >> 8;
+ i++;
+ }
+ fwrite(write_buffer, ii, 1, p_record);
+ p_record_length += ii;
+ break;
+
+ case CODEC_LAW:
+ d = write_buffer;
+ i = 0;
+ while(i < ii)
+ {
+ sample = p_record_buffer[p_record_buffer_readp]
+ + audio_law_to_s32[*data++];
+ p_record_buffer_readp = (p_record_buffer_readp + 1) & RECORD_BUFFER_MASK;
+ if (sample < SHORT_MIN) sample = SHORT_MIN;
+ if (sample > SHORT_MAX) sample = SHORT_MAX;
+ *d++ = audio_s16_to_law[sample & 0xffff];
+ i++;
+ }
+ fwrite(write_buffer, ii, 1, p_record);
+ p_record_length += ii;
+ break;
+ }
+ length -= ii;
+ /* still data */
+ if (length)
+ goto different_again;
+ /* no data (maybe buffer) */
+ return;
+
+}
+