changeset 101:c08794028df4

Fully implemented. Needs testing, but it works on the Grateful Dead show I leeched through etree.org. :)
author Ryan C. Gordon <icculus@icculus.org>
date Wed, 03 Oct 2001 17:59:14 +0000
parents 6d9fdec2f708
children 72502bed0aef
files decoders/shn.c
diffstat 1 files changed, 1123 insertions(+), 46 deletions(-) [+]
line wrap: on
line diff
--- a/decoders/shn.c	Wed Oct 03 12:25:34 2001 +0000
+++ b/decoders/shn.c	Wed Oct 03 17:59:14 2001 +0000
@@ -21,7 +21,7 @@
  * Shorten decoder for SDL_sound.
  *
  * This driver handles Shorten-compressed waveforms. Despite the fact that
- *  SHNs are generally used in online trading communities, they tend to be
+ *  SHNs are popular in online music trading communities, they tend to be
  *  much bigger than MP3s. If an MP3 crunches the waveform to 10-20 percent
  *  of its original size, SHNs only go to about 50-60%. Why do the Phish fans
  *  of the world use this format then? Rabid music traders appreciate the
@@ -34,7 +34,7 @@
  * Shorten homepage: http://www.softsound.com/Shorten.html
  *
  * The Shorten format was gleaned from the shorten codebase, by Tony
- *  Robinson and SoftSound Limited, but none of their code was used here.
+ *  Robinson and SoftSound Limited.
  *
  * Please see the file LICENSE in the source's root directory.
  *
@@ -76,6 +76,252 @@
 };
 
 
+#define SHN_BUFSIZ  512
+
+typedef struct
+{
+    Sint32 version;
+    Sint32 datatype;
+    Sint32 nchan;
+    Sint32 blocksize;
+    Sint32 maxnlpc;
+    Sint32 nmean;
+    Sint32 nwrap;
+    Sint32 **buffer;
+    Sint32 **offset;
+    Sint32 *qlpc;
+    Sint32 lpcqoffset;
+    Sint32 bitshift;
+    int nbitget;
+    int nbyteget;
+    Uint8 *getbuf;
+    Uint8 *getbufp;
+    Uint32 gbuffer;
+    Uint8 *backBuffer;
+    Uint32 backBufferSize;
+    Uint32 backBufLeft;
+} shn_t;
+
+
+static const Uint32 mask_table[] =
+{
+    0x00000000, 0x00000001, 0x00000003, 0x00000007, 0x0000000F, 0x0000001F,
+    0x0000003F, 0x0000007F, 0x000000FF, 0x000001FF, 0x000003FF, 0x000007FF,
+    0x00000FFF, 0x00001FFF, 0x00003FFF, 0x00007FFF, 0x0000FFFF, 0x0001FFFF,
+    0x0003FFFF, 0x0007FFFF, 0x000FFFFF, 0x001FFFFF, 0x003FFFFF, 0x007FFFFF,
+    0x00FFFFFF, 0x01FFFFFF, 0x03FFFFFF, 0x07FFFFFF, 0x0FFFFFFF, 0x1FFFFFFF,
+    0x3FFFFFFF, 0x7FFFFFFF, 0xFFFFFFFF
+};
+
+
+static const Uint8 ulaw_outward[13][256] = {
+{127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,255,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128},
+{112,114,116,118,120,122,124,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,113,115,117,119,121,123,125,255,253,251,249,247,245,243,241,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,252,250,248,246,244,242,240},
+{96,98,100,102,104,106,108,110,112,113,114,116,117,118,120,121,122,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,97,99,101,103,105,107,109,111,115,119,123,255,251,247,243,239,237,235,233,231,229,227,225,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,250,249,248,246,245,244,242,241,240,238,236,234,232,230,228,226,224},
+{80,82,84,86,88,90,92,94,96,97,98,100,101,102,104,105,106,108,109,110,112,113,114,115,116,117,118,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,81,83,85,87,89,91,93,95,99,103,107,111,119,255,247,239,235,231,227,223,221,219,217,215,213,211,209,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,246,245,244,243,242,241,240,238,237,236,234,233,232,230,229,228,226,225,224,222,220,218,216,214,212,210,208},
+{64,66,68,70,72,74,76,78,80,81,82,84,85,86,88,89,90,92,93,94,96,97,98,99,100,101,102,104,105,106,107,108,109,110,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,65,67,69,71,73,75,77,79,83,87,91,95,103,111,255,239,231,223,219,215,211,207,205,203,201,199,197,195,193,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,238,237,236,235,234,233,232,230,229,228,227,226,225,224,222,221,220,218,217,216,214,213,212,210,209,208,206,204,202,200,198,196,194,192},
+{49,51,53,55,57,59,61,63,64,66,67,68,70,71,72,74,75,76,78,79,80,81,82,84,85,86,87,88,89,90,92,93,94,95,96,97,98,99,100,101,102,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,50,52,54,56,58,60,62,65,69,73,77,83,91,103,255,231,219,211,205,201,197,193,190,188,186,184,182,180,178,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,230,229,228,227,226,225,224,223,222,221,220,218,217,216,215,214,213,212,210,209,208,207,206,204,203,202,200,199,198,196,195,194,192,191,189,187,185,183,181,179,177},
+{32,34,36,38,40,42,44,46,48,49,51,52,53,55,56,57,59,60,61,63,64,65,66,67,68,70,71,72,73,74,75,76,78,79,80,81,82,83,84,85,86,87,88,89,90,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,33,35,37,39,41,43,45,47,50,54,58,62,69,77,91,255,219,205,197,190,186,182,178,175,173,171,169,167,165,163,161,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,218,217,216,215,214,213,212,211,210,209,208,207,206,204,203,202,201,200,199,198,196,195,194,193,192,191,189,188,187,185,184,183,181,180,179,177,176,174,172,170,168,166,164,162,160},
+{16,18,20,22,24,26,28,30,32,33,34,36,37,38,40,41,42,44,45,46,48,49,50,51,52,53,55,56,57,58,59,60,61,63,64,65,66,67,68,69,70,71,72,73,74,75,76,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,17,19,21,23,25,27,29,31,35,39,43,47,54,62,77,255,205,190,182,175,171,167,163,159,157,155,153,151,149,147,145,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,204,203,202,201,200,199,198,197,196,195,194,193,192,191,189,188,187,186,185,184,183,181,180,179,178,177,176,174,173,172,170,169,168,166,165,164,162,161,160,158,156,154,152,150,148,146,144},
+{2,4,6,8,10,12,14,16,17,18,20,21,22,24,25,26,28,29,30,32,33,34,35,36,37,38,40,41,42,43,44,45,46,48,49,50,51,52,53,54,55,56,57,58,59,60,61,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,1,3,5,7,9,11,13,15,19,23,27,31,39,47,62,255,190,175,167,159,155,151,147,143,141,139,137,135,133,131,129,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,189,188,187,186,185,184,183,182,181,180,179,178,177,176,174,173,172,171,170,169,168,166,165,164,163,162,161,160,158,157,156,154,153,152,150,149,148,146,145,144,142,140,138,136,134,132,130,128},
+{1,2,4,5,6,8,9,10,12,13,14,16,17,18,19,20,21,22,24,25,26,27,28,29,30,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,3,7,11,15,23,31,47,255,175,159,151,143,139,135,131,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,158,157,156,155,154,153,152,150,149,148,147,146,145,144,142,141,140,138,137,136,134,133,132,130,129,128},
+{1,2,3,4,5,6,8,9,10,11,12,13,14,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,7,15,31,255,159,143,135,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,142,141,140,139,138,137,136,134,133,132,131,130,129,128},
+{1,2,3,4,5,6,7,8,9,10,11,12,13,14,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,15,255,143,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128},
+{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,0,255,254,253,252,251,250,249,248,247,246,245,244,243,242,241,240,239,238,237,236,235,234,233,232,231,230,229,228,227,226,225,224,223,222,221,220,219,218,217,216,215,214,213,212,211,210,209,208,207,206,205,204,203,202,201,200,199,198,197,196,195,194,193,192,191,190,189,188,187,186,185,184,183,182,181,180,179,178,177,176,175,174,173,172,171,170,169,168,167,166,165,164,163,162,161,160,159,158,157,156,155,154,153,152,151,150,149,148,147,146,145,144,143,142,141,140,139,138,137,136,135,134,133,132,131,130,129,128}
+};
+
+
+#ifndef	MIN_MACRO
+#define MIN_MACRO(a,b) (((a)<(b))?(a):(b))
+#endif
+
+#ifndef	MAX_MACRO
+#define MAX_MACRO(a,b) (((a)>(b))?(a):(b))
+#endif
+
+#define POSITIVE_ULAW_ZERO 0xff
+#define NEGATIVE_ULAW_ZERO 0x7f
+
+#define CAPMAXSCHAR(x)  ((x > 127) ? 127 : x)
+#define CAPMAXUCHAR(x)  ((x > 255) ? 255 : x)
+#define CAPMAXSHORT(x)  ((x > 32767) ? 32767 : x)
+#define CAPMAXUSHORT(x) ((x > 65535) ? 65535 : x)
+
+#define UNDEFINED_UINT      -1
+#define DEFAULT_BLOCK_SIZE  256
+#define DEFAULT_V0NMEAN     0
+#define DEFAULT_V2NMEAN     4
+#define DEFAULT_MAXNLPC     0
+#define DEFAULT_NCHAN       1
+#define DEFAULT_NSKIP       0
+#define DEFAULT_NDISCARD    0
+#define NBITPERLONG         32
+#define DEFAULT_MINSNR      256
+#define DEFAULT_QUANTERROR  0
+#define MINBITRATE          2.5
+
+#define MEAN_VERSION0   0
+#define MEAN_VERSION2   4
+
+#define SHN_FN_DIFF0        0
+#define SHN_FN_DIFF1        1
+#define SHN_FN_DIFF2        2
+#define SHN_FN_DIFF3        3
+#define SHN_FN_QUIT         4
+#define SHN_FN_BLOCKSIZE    5
+#define SHN_FN_BITSHIFT     6
+#define SHN_FN_QLPC         7
+#define SHN_FN_ZERO         8
+#define SHN_FN_VERBATIM     9
+
+#define SHN_TYPE_AU1              0
+#define SHN_TYPE_S8               1
+#define SHN_TYPE_U8               2
+#define SHN_TYPE_S16HL            3
+#define SHN_TYPE_U16HL            4
+#define SHN_TYPE_S16LH            5
+#define SHN_TYPE_U16LH            6
+#define SHN_TYPE_ULAW             7
+#define SHN_TYPE_AU2              8
+#define SHN_TYPE_AU3              9
+#define SHN_TYPE_ALAW            10
+#define SHN_TYPE_RIFF_WAVE       11
+#define SHN_TYPE_EOF             12
+#define SHN_TYPE_GENERIC_ULAW   128
+#define SHN_TYPE_GENERIC_ALAW   129
+
+#define SHN_FNSIZE                  2
+#define SHN_CHANNELSIZE             0
+#define SHN_TYPESIZE                4
+#define SHN_ULONGSIZE               2
+#define SHN_NSKIPSIZE               1
+#define SHN_LPCQSIZE                2
+#define SHN_LPCQUANT                5
+#define SHN_XBYTESIZE               7
+#define SHN_VERBATIM_CKSIZE_SIZE    5
+#define SHN_VERBATIM_BYTE_SIZE      8
+#define SHN_ENERGYSIZE              3
+#define SHN_BITSHIFTSIZE            2
+
+#define SHN_LPCQOFFSET_VER2 (1 << SHN_LPCQUANT)
+
+
+#define MAGIC_NUM 0x676B6A61   /* looks like "ajkg" as chars. */
+
+#ifndef M_LN2
+#define M_LN2   0.69314718055994530942
+#endif
+
+#ifndef M_PI
+#define M_PI    3.14159265358979323846
+#endif
+
+
+static int word_get(shn_t *shn, SDL_RWops *rw, Uint32 *word)
+{
+    if (shn->nbyteget < 4)
+    {
+        shn->nbyteget += SDL_RWread(rw, shn->getbuf, 1, SHN_BUFSIZ);
+        BAIL_IF_MACRO(shn->nbyteget < 4, NULL, 0);
+        shn->getbufp = shn->getbuf;
+    } /* if */
+
+    if (word != NULL)
+    {
+        *word = (((Sint32) shn->getbufp[0]) << 24) |
+                (((Sint32) shn->getbufp[1]) << 16) |
+                (((Sint32) shn->getbufp[2]) <<  8) |
+                (((Sint32) shn->getbufp[3])      );
+    } /* if */
+
+    shn->getbufp += 4;
+    shn->nbyteget -= 4;
+
+    return(1);
+} /* word_get */
+
+
+static int uvar_get(int nbin, shn_t *shn, SDL_RWops *rw, Sint32 *word)
+{
+    Sint32 result;
+
+    if (shn->nbitget == 0)
+    {
+        BAIL_IF_MACRO(!word_get(shn, rw, &shn->gbuffer), NULL, 0);
+        shn->nbitget = 32;
+    } /* if */
+
+    for (result = 0; !(shn->gbuffer & (1L << --shn->nbitget)); result++)
+    {
+        if (shn->nbitget == 0)
+        {
+            BAIL_IF_MACRO(!word_get(shn, rw, &shn->gbuffer), NULL, 0);
+            shn->nbitget = 32;
+        } /* if */
+    } /* for */
+
+    while (nbin != 0)
+    {
+        if (shn->nbitget >= nbin)
+        {
+            result = ( (result << nbin) |
+                        ((shn->gbuffer >> (shn->nbitget - nbin)) &
+                        mask_table[nbin]) );
+            shn->nbitget -= nbin;
+            break;
+        } /* if */
+        else
+        {
+            result = (result << shn->nbitget) |
+                     (shn->gbuffer & mask_table[shn->nbitget]);
+            BAIL_IF_MACRO(!word_get(shn, rw, &shn->gbuffer), NULL, 0);
+            nbin -= shn->nbitget;
+            shn->nbitget = 32;
+        } /* else */
+    } /* while */
+
+    if (word != NULL)
+        *word = result;
+
+    return(1);
+} /* uvar_get */
+
+
+static int var_get(int nbin, shn_t *shn, SDL_RWops *rw, Sint32 *word)
+{
+    BAIL_IF_MACRO(!uvar_get(nbin + 1, shn, rw, word), NULL, 0);
+
+    if ((*word) & 1)
+        *word = (Sint32) ~((*word) >> 1);
+    else
+        *word = (Sint32) ((*word) >> 1);
+
+    return(1);
+} /* var_get */
+
+
+static int ulong_get(shn_t *shn, SDL_RWops *rw, Sint32 *word)
+{
+    Sint32 nbit;
+    Sint32 retval;
+    BAIL_IF_MACRO(!uvar_get(SHN_ULONGSIZE, shn, rw, &nbit), NULL, 0);
+    BAIL_IF_MACRO(!uvar_get(nbit, shn, rw, &retval), NULL, 0);
+
+    if (word != NULL)
+        *word = retval;
+
+    return(1);
+} /* ulong_get */
+
+
+static inline int uint_get(int nbit, shn_t *shn, SDL_RWops *rw, Sint32 *word)
+{
+    return((shn->version == 0) ?
+                uvar_get(nbit, shn, rw, word) :
+                ulong_get(shn, rw, word));
+} /* uint_get */
+
+
 static int SHN_init(void)
 {
     return(1);  /* initialization always successful. */
@@ -88,19 +334,6 @@
 } /* SHN_quit */
 
 
-static Uint32 mask_table[] =
-{
-    0x00000000, 0x00000001, 0x00000003, 0x00000007, 0x0000000F, 0x0000001F,
-    0x0000003F, 0x0000007F, 0x000000FF, 0x000001FF, 0x000003FF, 0x000007FF,
-    0x00000FFF, 0x00001FFF, 0x00003FFF, 0x00007FFF, 0x0000FFFF, 0x0001FFFF,
-    0x0003FFFF, 0x0007FFFF, 0x000FFFFF, 0x001FFFFF, 0x003FFFFF, 0x007FFFFF,
-    0x00FFFFFF, 0x01FFFFFF, 0x03FFFFFF, 0x07FFFFFF, 0x0FFFFFFF, 0x1FFFFFFF,
-    0x3FFFFFFF, 0x7FFFFFFF, 0xFFFFFFFF
-};
-
-
-#define MAGIC_NUM 0x676B6A61   /* looks like "ajkg" as chars. */
-
 /*
  * Look through the whole file for a SHN magic number. This is costly, so
  *  it should only be done if the user SWEARS they have a Shorten stream...
@@ -115,7 +348,7 @@
     {
         BAIL_IF_MACRO(SDL_RWread(rw, &ch, sizeof (ch), 1) != 1, NULL, -1);
         word = ((word << 8) & 0xFFFFFF00) | ch;
-        if (SDL_SwapLE32(word) == MAGIC_NUM)
+        if (SDL_SwapBE32(word) == MAGIC_NUM)
         {
             BAIL_IF_MACRO(SDL_RWread(rw, &ch, sizeof (ch), 1) != 1, NULL, -1);
             return((int) ch);
@@ -127,7 +360,7 @@
 
 
 /* look for the magic number in the RWops and see what kind of file this is. */
-static inline int determine_shn_version(Sound_Sample *sample)
+static inline int determine_shn_version(Sound_Sample *sample, const char *ext)
 {
     SDL_RWops *rw = ((Sound_SampleInternal *) sample->opaque)->rw;
     Uint32 magic;
@@ -142,7 +375,7 @@
      */
 
     if (__Sound_strcasecmp(ext, "shn") == 0)
-        return(extended_shn_magic_search(sample);
+        return(extended_shn_magic_search(sample));
 
     BAIL_IF_MACRO(SDL_RWread(rw, &magic, sizeof (magic), 1) != 1, NULL, -1);
     BAIL_IF_MACRO(SDL_SwapLE32(magic) != MAGIC_NUM, "SHN: Not a SHN file", -1);
@@ -153,59 +386,903 @@
 } /* determine_shn_version */
 
 
+static int init_shn_offset(Sint32 **offset, int nchan, int nblock, int ftype)
+{
+    Sint32 mean = 0;
+    int chan;
+
+    switch (ftype)
+    {
+        case SHN_TYPE_AU1:
+        case SHN_TYPE_S8:
+        case SHN_TYPE_S16HL:
+        case SHN_TYPE_S16LH:
+        case SHN_TYPE_ULAW:
+        case SHN_TYPE_AU2:
+        case SHN_TYPE_AU3:
+        case SHN_TYPE_ALAW:
+            mean = 0;
+            break;
+        case SHN_TYPE_U8:
+            mean = 0x80;
+            break;
+        case SHN_TYPE_U16HL:
+        case SHN_TYPE_U16LH:
+            mean = 0x8000;
+            break;
+        default:
+            BAIL_MACRO("SHN: unknown file type", 0);
+    } /* switch */
+
+    for(chan = 0; chan < nchan; chan++)
+    {
+        int i;
+        for(i = 0; i < nblock; i++)
+            offset[chan][i] = mean;
+    } /* for */
+} /* init_shn_offset */
+
+
+static inline Uint16 cvt_shnftype_to_sdlfmt(Sint16 shntype)
+{
+    switch (shntype)
+    {
+        case SHN_TYPE_S8:
+            return(AUDIO_S8);
+
+        case SHN_TYPE_ALAW:
+        case SHN_TYPE_ULAW:
+        case SHN_TYPE_AU1:
+        case SHN_TYPE_AU2:
+        case SHN_TYPE_AU3:
+        case SHN_TYPE_U8:
+            return(AUDIO_U8);
+
+        case SHN_TYPE_S16HL:
+            return(AUDIO_S16MSB);
+
+        case SHN_TYPE_S16LH:
+            return(AUDIO_S16LSB);
+
+        case SHN_TYPE_U16HL:
+            return(AUDIO_U16MSB);
+
+        case SHN_TYPE_U16LH:
+            return(AUDIO_U16LSB);
+    } /* switch */
+
+    return(0);
+} /* cvt_shnftype_to_sdlfmt */
+
+
+static inline int skip_bits(shn_t *shn, SDL_RWops *rw)
+{
+    int i;
+    Sint32 skip;
+    Sint32 trash;
+
+    BAIL_IF_MACRO(!uint_get(SHN_NSKIPSIZE, shn, rw, &skip), NULL, 0);
+    for(i = 0; i < skip; i++)
+    {
+        BAIL_IF_MACRO(!uint_get(SHN_XBYTESIZE, shn, rw, &trash), NULL, 0);
+    } /* for */
+
+    return(1);
+} /* skip_bits */
+
+
+static Sint32 **shn_long2d(Uint32 n0, Uint32 n1)
+{
+    Sint32 **array0;
+    Uint32 size = (n0 * sizeof (Sint32 *)) + (n0 * n1 * sizeof (Sint32));
+
+    array0 = (Sint32 **) malloc(size);
+    if (array0 != NULL)
+    {
+        int i;
+        Sint32 *array1 = (Sint32 *) (array0 + n0);
+        for(i = 0; i < n0; i++)
+            array0[i] = array1 + (i * n1);
+    } /* if */
+
+    return(array0);
+} /* shn_long2d */
+
+#define riffID 0x46464952  /* "RIFF", in ascii. */
+#define waveID 0x45564157  /* "WAVE", in ascii. */
+#define fmtID  0x20746D66  /* "fmt ", in ascii. */
+#define dataID 0x61746164  /* "data", in ascii. */
+
+static int verb_ReadLE32(shn_t *shn, SDL_RWops *rw, Uint32 *word)
+{
+    int i;
+    Uint8 chars[4];
+    Sint32 byte;
+
+    for (i = 0; i < 4; i++)
+    {
+        if (!uvar_get(SHN_VERBATIM_BYTE_SIZE, shn, rw, &byte))
+            return(0);
+        chars[i] = (Uint8) byte;
+    } /* for */
+
+    memcpy(word, chars, sizeof (*word));
+    *word = SDL_SwapLE32(*word);
+
+    return(1);
+} /* verb_ReadLE32 */
+
+
+static int verb_ReadLE16(shn_t *shn, SDL_RWops *rw, Uint16 *word)
+{
+    int i;
+    Uint8 chars[2];
+    Sint32 byte;
+
+    for (i = 0; i < 2; i++)
+    {
+        if (!uvar_get(SHN_VERBATIM_BYTE_SIZE, shn, rw, &byte))
+            return(0);
+        chars[i] = (Uint8) byte;
+    } /* for */
+
+    memcpy(word, chars, sizeof (*word));
+    *word = SDL_SwapLE16(*word);
+
+    return(1);
+} /* verb_ReadLE16 */
+
+
+static inline int parse_riff_header(shn_t *shn, Sound_Sample *sample)
+{
+    Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
+    SDL_RWops *rw = internal->rw;
+    Uint16 u16;
+    Uint32 u32;
+    Sint32 cklen;
+
+    BAIL_IF_MACRO(!uvar_get(SHN_VERBATIM_CKSIZE_SIZE, shn, rw, &cklen), NULL, 0);
+
+    BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* RIFF header */
+    BAIL_IF_MACRO(u32 != riffID, "SHN: No RIFF header.", 0);
+    BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* length */
+
+    BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* WAVE header */
+    BAIL_IF_MACRO(u32 != waveID, "SHN: No WAVE header.", 0);
+
+    BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* 'fmt ' header */
+    BAIL_IF_MACRO(u32 != fmtID,  "SHN: No 'fmt ' header.", 0);
+
+    BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* chunksize */
+    BAIL_IF_MACRO(!verb_ReadLE16(shn, rw, &u16), NULL, 0); /* format */
+    BAIL_IF_MACRO(!verb_ReadLE16(shn, rw, &u16), NULL, 0); /* channels */
+    sample->actual.channels = u16;
+    BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* sample rate */
+    sample->actual.rate = u32;
+
+    BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* bytespersec */
+    BAIL_IF_MACRO(!verb_ReadLE16(shn, rw, &u16), NULL, 0); /* blockalign */
+    BAIL_IF_MACRO(!verb_ReadLE16(shn, rw, &u16), NULL, 0); /* bitspersample */
+
+    BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* 'data' header */
+    BAIL_IF_MACRO(u32 != dataID,  "SHN: No 'data' header.", 0);
+    BAIL_IF_MACRO(!verb_ReadLE32(shn, rw, &u32), NULL, 0); /* chunksize */
+
+    return(1);
+} /* parse_riff_header */
+
+
 static int SHN_open(Sound_Sample *sample, const char *ext)
 {
     Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
     SDL_RWops *rw = internal->rw;
-    int shn_version = determine_shn_version(sample, ext);
-    int mean = MEAN_VERSION2;
+    shn_t _shn;
+    shn_t *shn = &_shn;  /* malloc and copy later. */
+    Sint32 cmd;
+    Sint32 chan;
+
+    memset(shn, '\0', sizeof (shn_t));
+    shn->getbufp = shn->getbuf = (Uint8 *) malloc(SHN_BUFSIZ);
+    shn->datatype = SHN_TYPE_EOF;
+    shn->nchan = DEFAULT_NCHAN;
+    shn->blocksize = DEFAULT_BLOCK_SIZE;
+    shn->maxnlpc = DEFAULT_MAXNLPC;
+    shn->nmean = UNDEFINED_UINT;
+    shn->version = determine_shn_version(sample, ext);
+
+    if (shn->version == -1) goto shn_open_puke;
+    if (!uint_get(SHN_TYPESIZE, shn, rw, &shn->datatype)) goto shn_open_puke;
+    if (!uint_get(SHN_CHANNELSIZE, shn, rw, &shn->nchan)) goto shn_open_puke;
+
+    sample->actual.format = cvt_shnftype_to_sdlfmt(shn->datatype);
+    if (sample->actual.format == 0)
+    {
+        SDL_SetError(ERR_UNSUPPORTED_FORMAT);
+        goto shn_open_puke;
+    } /* if */
+
+    if (shn->version > 0)
+    {
+        int rc = uint_get((int) (log((double) DEFAULT_BLOCK_SIZE) / M_LN2),
+                           shn, rw, &shn->blocksize);
+        if (!rc)  goto shn_open_puke;;
+        if (!uint_get(SHN_LPCQSIZE, shn, rw, &shn->maxnlpc)) goto shn_open_puke;
+        if (!uint_get(0, shn, rw, &shn->nmean)) goto shn_open_puke;
+        if (!skip_bits(shn, rw)) goto shn_open_puke;
+    } /* else */
+
+    shn->nwrap = (shn->maxnlpc > 3) ? shn->maxnlpc : 3;
+
+    /* grab some space for the input buffer */
+    shn->buffer = shn_long2d((Uint32) shn->nchan, shn->blocksize + shn->nwrap);
+    shn->offset = shn_long2d((Uint32) shn->nchan, MAX_MACRO(1, shn->nmean));
+
+    for (chan = 0; chan < shn->nchan; chan++)
+    {
+        int i;
+        for(i = 0; i < shn->nwrap; i++)
+            shn->buffer[chan][i] = 0;
+        shn->buffer[chan] += shn->nwrap;
+    } /* for */
 
-    BAIL_IF_MACRO(shn_version == -1, NULL, 0);
-    if (shn_version < 2)  /* downgrade? */
-        mean = MEAN_VERSION0;
+    if (shn->maxnlpc > 0)
+    {
+        shn->qlpc = (int *) malloc((Uint32) (shn->maxnlpc * sizeof (Sint32)));
+        if (shn->qlpc == NULL)
+        {
+            Sound_SetError(ERR_OUT_OF_MEMORY);
+            goto shn_open_puke;
+        } /* if */
+    } /* if */
+
+    if (shn->version > 1)
+        shn->lpcqoffset = SHN_LPCQOFFSET_VER2;
+
+    init_shn_offset(shn->offset, shn->nchan,
+                    MAX_MACRO(1, shn->nmean), shn->datatype);
+
+    if ( (!uvar_get(SHN_FNSIZE, shn, rw, &cmd)) ||
+         (cmd != SHN_FN_VERBATIM) ||
+         (!parse_riff_header(shn, sample)) )
+    {
+        if (cmd != SHN_FN_VERBATIM)
+            Sound_SetError("SHN: Expected VERBATIM function");
+
+        goto shn_open_puke;
+        return(0);
+    } /* if */
+
+    shn = (shn_t *) malloc(sizeof (shn_t));
+    if (shn == NULL)
+    {
+        Sound_SetError(ERR_OUT_OF_MEMORY);
+        goto shn_open_puke;
+    } /* if */
+
+    memcpy(shn, &_shn, sizeof (shn_t));
+    internal->decoder_private = shn;
+
+    SNDDBG(("SHN: Accepting data stream.\n"));
+    sample->flags = SOUND_SAMPLEFLAG_NONE;
+    return(1); /* we'll handle this data. */
+
+shn_open_puke:
+    if (_shn.getbuf)
+        free(_shn.getbuf);
+    if (_shn.buffer != NULL)
+        free(_shn.buffer);
+    if (_shn.offset != NULL)
+        free(_shn.offset);
+    if (_shn.qlpc != NULL)
+        free(_shn.qlpc);
+
+    return(0);
+} /* SHN_open */
 
 
+void fix_bitshift(Sint32 *buffer, int nitem, int bitshift, int ftype)
+{
+    int i;
 
-    SNDDBG(("SHN: Accepting data stream.\n"));
-    set up sample->actual;
-    sample->flags = SOUND_SAMPLEFLAG_NONE;
-    return(1); /* we'll handle this data. */
-} /* SHN_open */
+    if (ftype == SHN_TYPE_AU1)
+    {
+        for (i = 0; i < nitem; i++)
+            buffer[i] = ulaw_outward[bitshift][buffer[i] + 128];
+    } /* if */
+    else if (ftype == SHN_TYPE_AU2)
+    {
+        for(i = 0; i < nitem; i++)
+        {
+            if (buffer[i] >= 0)
+                buffer[i] = ulaw_outward[bitshift][buffer[i] + 128];
+            else if (buffer[i] == -1)
+                buffer[i] = NEGATIVE_ULAW_ZERO;
+            else
+                buffer[i] = ulaw_outward[bitshift][buffer[i] + 129];
+        } /* for */
+    } /* else if */
+    else
+    {
+        if (bitshift != 0)
+        {
+            for(i = 0; i < nitem; i++)
+                buffer[i] <<= bitshift;
+        } /* if */
+    } /* else */
+} /* fix_bitshift */
 
 
 static void SHN_close(Sound_Sample *sample)
 {
     Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
-    clean up anything you put into internal->decoder_private;
+    shn_t *shn = (shn_t *) internal->decoder_private;
+
+    if (shn->qlpc != NULL)
+        free(shn->qlpc);
+
+    if (shn->backBuffer != NULL)
+        free(shn->backBuffer);
+
+    if (shn->offset != NULL)
+        free(shn->offset);
+
+    if (shn->buffer != NULL)
+        free(shn->buffer);
+
+    if (shn->getbuf != NULL)
+        free(shn->getbuf);
+
+    free(shn);
 } /* SHN_close */
 
 
+/* xLaw conversions... */
+
+/* adapted by ajr for int input */
+static Uint8 Slinear2ulaw(int sample)
+{
+/*
+** This routine converts from linear to ulaw.
+**
+** Craig Reese: IDA/Supercomputing Research Center
+** Joe Campbell: Department of Defense
+** 29 September 1989
+**
+** References:
+** 1) CCITT Recommendation G.711  (very difficult to follow)
+** 2) "A New Digital Technique for Implementation of Any
+**     Continuous PCM Companding Law," Villeret, Michel,
+**     et al. 1973 IEEE Int. Conf. on Communications, Vol 1,
+**     1973, pg. 11.12-11.17
+** 3) MIL-STD-188-113,"Interoperability and Performance Standards
+**     for Analog-to_Digital Conversion Techniques,"
+**     17 February 1987
+**
+** Input: Signed 16 bit linear sample
+** Output: 8 bit ulaw sample
+*/
+
+#define BIAS 0x84   /* define the add-in bias for 16 bit samples */
+#define CLIP 32635
+
+  int sign, exponent, mantissa;
+  Uint8 ulawbyte;
+  static const int exp_lut[256] = {0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,
+                                   4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
+                                   5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+                                   5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
+                                   6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+                                   6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+                                   6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+                                   6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
+                                   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+                                   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+                                   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+                                   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+                                   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+                                   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+                                   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
+                                   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7};
+
+    /* Get the sample into sign-magnitude. */
+    if (sample >= 0)
+        sign = 0;
+    else
+    {
+        sign = 0x80;
+        sample = -sample;
+    } /* else */
+
+    /* clip the magnitude */
+    if (sample > CLIP)
+        sample = CLIP;
+
+    /* Convert from 16 bit linear to ulaw. */
+    sample = sample + BIAS;
+    exponent = exp_lut[( sample >> 7 ) & 0xFF];
+    mantissa = (sample >> (exponent + 3)) & 0x0F;
+    ulawbyte = ~(sign | (exponent << 4) | mantissa);
+
+    return(ulawbyte);
+} /* Slinear2ulaw */
+
+
+/* this is derived from the Sun code - it is a bit simpler and has int input */
+#define QUANT_MASK      (0xf)           /* Quantization field mask. */
+#define NSEGS           (8)             /* Number of A-law segments. */
+#define SEG_SHIFT       (4)             /* Left shift for segment number. */
+
+
+static Uint8 Slinear2alaw(Sint32 linear)
+{
+    int	seg;
+    Uint8 aval, mask;
+    static const Sint32 seg_aend[NSEGS] =
+    {
+        0x1f,0x3f,0x7f,0xff,0x1ff,0x3ff,0x7ff,0xfff
+    };
+
+    linear >>= 3;
+    if(linear >= 0)
+        mask = 0xd5;		/* sign (7th) bit = 1 */
+    else
+    {
+        mask = 0x55;		/* sign bit = 0 */
+        linear = -linear - 1;
+    } /* else */
+
+    /* Convert the scaled magnitude to segment number. */
+    for (seg = 0; (seg < NSEGS) && (linear > seg_aend[seg]); seg++);
+
+    /* Combine the sign, segment, and quantization bits. */
+    if (seg >= NSEGS)    /* out of range, return maximum value. */
+        return((Uint8) (0x7F ^ mask));
+
+    aval = (Uint8) seg << SEG_SHIFT;
+    if (seg < 2)
+        aval |= (linear >> 1) & QUANT_MASK;
+    else
+        aval |= (linear >> seg) & QUANT_MASK;
+
+    return (aval ^ mask);
+} /* Slinear2alaw */
+
+
+/* convert from signed ints to a given type and write */
+static Uint32 put_to_buffers(Sound_Sample *sample, Uint32 bw)
+{
+    Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
+    shn_t *shn = (shn_t *) internal->decoder_private;
+    int i, chan;
+    Sint32 *data0 = shn->buffer[0];
+    Sint32 nitem = shn->blocksize;
+    int datasize = ((sample->actual.format & 0xFF) / 8);
+    Uint32 bsiz = shn->nchan * nitem * datasize;
+
+    assert(shn->backBufLeft == 0);
+
+    if (shn->backBufferSize < bsiz)
+    {
+        void *rc = realloc(shn->backBuffer, bsiz);
+        if (rc == NULL)
+        {
+            sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+            BAIL_MACRO(ERR_OUT_OF_MEMORY, 0);
+        } /* if */
+        shn->backBuffer = (Uint8 *) rc;
+        shn->backBufferSize = bsiz;
+    } /* if */
+
+    switch (shn->datatype)
+    {
+        case SHN_TYPE_AU1: /* leave the conversion to fix_bitshift() */
+        case SHN_TYPE_AU2:
+        {
+            Uint8 *writebufp = shn->backBuffer;
+            if (shn->nchan == 1)
+            {
+                for (i = 0; i < nitem; i++)
+                    *writebufp++ = data0[i];
+            } /* if */
+            else
+            {
+                for (i = 0; i < nitem; i++)
+                {
+                    for (chan = 0; chan < shn->nchan; chan++)
+                        *writebufp++ = shn->buffer[chan][i];
+                } /* for */
+            } /* else */
+        } /* case */
+        break;
+
+        case SHN_TYPE_U8:
+        {
+            Uint8 *writebufp = shn->backBuffer;
+            if (shn->nchan == 1)
+            {
+                for (i = 0; i < nitem; i++)
+                    *writebufp++ = CAPMAXUCHAR(data0[i]);
+            } /* if */
+            else
+            {
+                for (i = 0; i < nitem; i++)
+                {
+                    for (chan = 0; chan < shn->nchan; chan++)
+                        *writebufp++ = CAPMAXUCHAR(shn->buffer[chan][i]);
+                } /* for */
+            } /* else */
+        } /* case */
+        break;
+
+        case SHN_TYPE_S8:
+        {
+            Sint8 *writebufp = (Sint8 *) shn->backBuffer;
+            if (shn->nchan == 1)
+            {
+                for(i = 0; i < nitem; i++)
+                    *writebufp++ = CAPMAXSCHAR(data0[i]);
+            } /* if */
+            else
+            {
+                for(i = 0; i < nitem; i++)
+                {
+                    for(chan = 0; chan < shn->nchan; chan++)
+                        *writebufp++ = CAPMAXSCHAR(shn->buffer[chan][i]);
+                } /* for */
+            } /* else */
+        } /* case */
+        break;
+
+        case SHN_TYPE_S16HL:
+        case SHN_TYPE_S16LH:
+        {
+            Sint16 *writebufp = (Sint16 *) shn->backBuffer;
+            if (shn->nchan == 1)
+            {
+                for (i = 0; i < nitem; i++)
+                    *writebufp++ = CAPMAXSHORT(data0[i]);
+            } /* if */
+            else
+            {
+                for (i = 0; i < nitem; i++)
+                {
+                    for (chan = 0; chan < shn->nchan; chan++)
+                        *writebufp++ = CAPMAXSHORT(shn->buffer[chan][i]);
+                } /* for */
+            } /* else */
+        } /* case */
+        break;
+
+        case SHN_TYPE_U16HL:
+        case SHN_TYPE_U16LH:
+        {
+            Uint16 *writebufp = (Uint16 *) shn->backBuffer;
+            if (shn->nchan == 1)
+            {
+                for (i = 0; i < nitem; i++)
+                    *writebufp++ = CAPMAXUSHORT(data0[i]);
+            } /* if */
+            else
+            {
+                for (i = 0; i < nitem; i++)
+                {
+                    for (chan = 0; chan < shn->nchan; chan++)
+                        *writebufp++ = CAPMAXUSHORT(shn->buffer[chan][i]);
+                } /* for */
+            } /* else */
+        } /* case */
+        break;
+
+        case SHN_TYPE_ULAW:
+        {
+            Uint8 *writebufp = shn->backBuffer;
+            if (shn->nchan == 1)
+            {
+                for(i = 0; i < nitem; i++)
+                    *writebufp++ = Slinear2ulaw(CAPMAXSHORT((data0[i] << 3)));
+            } /* if */
+            else
+            {
+                for(i = 0; i < nitem; i++)
+                {
+                    for(chan = 0; chan < shn->nchan; chan++)
+                        *writebufp++ = Slinear2ulaw(CAPMAXSHORT((shn->buffer[chan][i] << 3)));
+                } /* for */
+            } /* else */
+        } /* case */
+        break;
+
+        case SHN_TYPE_AU3:
+        {
+            Uint8 *writebufp = shn->backBuffer;
+            if (shn->nchan == 1)
+            {
+                for (i = 0; i < nitem; i++)
+                    if(data0[i] < 0)
+                        *writebufp++ = (127 - data0[i]) ^ 0xd5;
+                    else
+                        *writebufp++ = (data0[i] + 128) ^ 0x55;
+            } /* if */
+            else
+            {
+                for (i = 0; i < nitem; i++)
+                {
+                    for (chan = 0; chan < shn->nchan; chan++)
+                    {
+                        if (shn->buffer[chan][i] < 0)
+                            *writebufp++ = (127 - shn->buffer[chan][i]) ^ 0xd5;
+                        else
+                            *writebufp++ = (shn->buffer[chan][i] + 128) ^ 0x55;
+                    } /* for */
+                } /* for */
+            } /* else */
+        } /* case */
+        break;
+
+        case SHN_TYPE_ALAW:
+        {
+            Uint8 *writebufp = shn->backBuffer;
+            if (shn->nchan == 1)
+            {
+                for (i = 0; i < nitem; i++)
+                    *writebufp++ = Slinear2alaw(CAPMAXSHORT((data0[i] << 3)));
+            } /* if */
+            else
+            {
+                for (i = 0; i < nitem; i++)
+                {
+                    for(chan = 0; chan < shn->nchan; chan++)
+                        *writebufp++ = Slinear2alaw(CAPMAXSHORT((shn->buffer[chan][i] << 3)));
+                } /* for */
+            }/* else */
+        } /* case */
+        break;
+    } /* switch */
+
+    i = MIN_MACRO(internal->buffer_size - bw, bsiz);
+    memcpy(internal->buffer + bw, shn->backBuffer, i);
+    shn->backBufLeft = bsiz - i;
+    memcpy(shn->backBuffer, shn->backBuffer + i, shn->backBufLeft);
+    return(i);
+} /* put_to_buffers */
+
+
+#define ROUNDEDSHIFTDOWN(x, n) (((n) == 0) ? (x) : ((x) >> ((n) - 1)) >> 1)
+
 static Uint32 SHN_read(Sound_Sample *sample)
 {
-    Uint32 retval;
+    Uint32 retval = 0;
+    Sint32 chan = 0;
+    Uint32 cpyBytes = 0;
     Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
+    SDL_RWops *rw = internal->rw;
+    shn_t *shn = (shn_t *) internal->decoder_private;
+    Sint32 cmd;
+
+    assert(shn->backBufLeft >= 0);
+
+        /* see if there are leftovers to copy... */
+    if (shn->backBufLeft > 0)
+    {
+        retval = MIN_MACRO(shn->backBufLeft, internal->buffer_size);
+        memcpy(internal->buffer, shn->backBuffer, retval);
+        shn->backBufLeft -= retval;
+        memcpy(shn->backBuffer, shn->backBuffer + retval, shn->backBufLeft);
+    } /* if */
+
+    assert((shn->backBufLeft == 0) || (retval == internal->buffer_size));
+
+    /* get commands from file and execute them */
+    while (retval < internal->buffer_size)
+    {
+        if (!uvar_get(SHN_FNSIZE, shn, rw, &cmd))
+        {
+            sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+            return(retval);
+        } /* if */
+
+        if (cmd == SHN_FN_QUIT)
+        {
+            sample->flags |= SOUND_SAMPLEFLAG_EOF;
+            return(retval);
+        } /* if */
+
+        switch(cmd)
+        {
+            case SHN_FN_ZERO:
+            case SHN_FN_DIFF0:
+            case SHN_FN_DIFF1:
+            case SHN_FN_DIFF2:
+            case SHN_FN_DIFF3:
+            case SHN_FN_QLPC:
+            {
+                Sint32 i;
+                Sint32 coffset, *cbuffer = shn->buffer[chan];
+                Sint32 resn = 0, nlpc, j;
 
-        /*
-         * We don't actually do any decoding, so we read the fmt data
-         *  directly into the internal buffer...
-         */
-    retval = SDL_RWread(internal->rw, internal->buffer,
-                        1, internal->buffer_size);
+                if (cmd != SHN_FN_ZERO)
+                {
+                    if (!uvar_get(SHN_ENERGYSIZE, shn, rw, &resn))
+                    {
+                        sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                        return(retval);
+                    } /* if */
+
+                    /* version 0 differed in definition of var_get */
+                    if (shn->version == 0)
+                        resn--;
+                } /* if */
+
+                /* find mean offset : N.B. this code duplicated */
+                if (shn->nmean == 0)
+                    coffset = shn->offset[chan][0];
+                else
+                {
+                    Sint32 sum = (shn->version < 2) ? 0 : shn->nmean / 2;
+                    for (i = 0; i < shn->nmean; i++)
+                        sum += shn->offset[chan][i];
+
+                    if (shn->version < 2)
+                        coffset = sum / shn->nmean;
+                    else
+                        coffset = ROUNDEDSHIFTDOWN(sum / shn->nmean, shn->bitshift);
+                } /* else */
 
-    (or whatever. Do some decoding here...)
+                switch (cmd)
+                {
+                    case SHN_FN_ZERO:
+                        for (i = 0; i < shn->blocksize; i++)
+                            cbuffer[i] = 0;
+                        break;
+
+                    case SHN_FN_DIFF0:
+                        for(i = 0; i < shn->blocksize; i++)
+                        {
+                            if (!var_get(resn, shn, rw, &cbuffer[i]))
+                            {
+                                sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                                return(retval);
+                            } /* if */
+                            cbuffer[i] += coffset;
+                        } /* for */
+                        break;
+
+                    case SHN_FN_DIFF1:
+                        for(i = 0; i < shn->blocksize; i++)
+                        {
+                            if (!var_get(resn, shn, rw, &cbuffer[i]))
+                            {
+                                sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                                return(retval);
+                            } /* if */
+                            cbuffer[i] += cbuffer[i - 1];
+                        } /* for */
+                        break;
 
-        /* Make sure the read went smoothly... */
-    if (retval == 0)
-        sample->flags |= SOUND_SAMPLEFLAG_EOF;
+                    case SHN_FN_DIFF2:
+                        for (i = 0; i < shn->blocksize; i++)
+                        {
+                            if (!var_get(resn, shn, rw, &cbuffer[i]))
+                            {
+                                sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                                return(retval);
+                            } /* if */
+                            cbuffer[i] += (2 * cbuffer[i-1] - cbuffer[i-2]);
+                        } /* for */
+                        break;
+
+                    case SHN_FN_DIFF3:
+                        for (i = 0; i < shn->blocksize; i++)
+                        {
+                            if (!var_get(resn, shn, rw, &cbuffer[i]))
+                            {
+                                sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                                return(retval);
+                            } /* if */
+                            cbuffer[i] += 3 * (cbuffer[i - 1] - cbuffer[i - 2]) + cbuffer[i - 3];
+                        } /* for */
+                        break;
+
+                    case SHN_FN_QLPC:
+                        if (!uvar_get(SHN_LPCQSIZE, shn, rw, &nlpc))
+                        {
+                            sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                            return(retval);
+                        } /* if */
+
+                        for(i = 0; i < nlpc; i++)
+                        {
+                            if (!var_get(SHN_LPCQUANT, shn, rw, &shn->qlpc[i]))
+                            {
+                                sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                                return(retval);
+                            } /* if */
+                        } /* for */
+
+                        for(i = 0; i < nlpc; i++)
+                            cbuffer[i - nlpc] -= coffset;
+
+                        for(i = 0; i < shn->blocksize; i++)
+                        {
+                            Sint32 sum = shn->lpcqoffset;
+
+                            for(j = 0; j < nlpc; j++)
+                                sum += shn->qlpc[j] * cbuffer[i - j - 1];
+
+                            if (!var_get(resn, shn, rw, &cbuffer[i]))
+                            {
+                                sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                                return(retval);
+                            } /* if */
+                            cbuffer[i] += (sum >> SHN_LPCQUANT);
+                        } /* for */
 
-    else if (retval == -1)
-        sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                        if (coffset != 0)
+                        {
+                            for(i = 0; i < shn->blocksize; i++)
+                                cbuffer[i] += coffset;
+                        } /* if */
+
+                        break;
+                } /* switch */
+
+                /* store mean value if appropriate : N.B. Duplicated code */
+                if (shn->nmean > 0)
+                {
+                    Sint32 sum = (shn->version < 2) ? 0 : shn->blocksize / 2;
+                    for (i = 0; i < shn->blocksize; i++)
+                        sum += cbuffer[i];
+
+                    for(i = 1; i < shn->nmean; i++)
+                        shn->offset[chan][i - 1] = shn->offset[chan][i];
+
+                    if (shn->version < 2)
+                        shn->offset[chan][shn->nmean - 1] = sum / shn->blocksize;
+                    else
+                        shn->offset[chan][shn->nmean - 1] = (sum / shn->blocksize) << shn->bitshift;
+                } /* if */
+
+                /* do the wrap */
+                for(i = -shn->nwrap; i < 0; i++)
+                    cbuffer[i] = cbuffer[i + shn->blocksize];
+
+                fix_bitshift(cbuffer, shn->blocksize, shn->bitshift, shn->datatype);
 
-        /* (next call this EAGAIN may turn into an EOF or error.) */
-    else if (retval < internal->buffer_size)
-        sample->flags |= SOUND_SAMPLEFLAG_EAGAIN;
+                if (chan == shn->nchan - 1)
+                {
+                    retval += put_to_buffers(sample, retval);
+                    if (sample->flags & SOUND_SAMPLEFLAG_ERROR)
+                        return(retval);
+                } /* if */
+
+                chan = (chan + 1) % shn->nchan;
+                break;
+            } /* case */
 
-    (or whatever. retval == number of bytes you put in internal->buffer).
+            case SHN_FN_BLOCKSIZE:
+                if (!uint_get((int) (log((double) shn->blocksize) / M_LN2),
+                              shn, rw, &shn->blocksize))
+                {
+                    sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                    return(retval);
+                } /* if */
+                break;
+
+            case SHN_FN_BITSHIFT:
+                if (!uvar_get(SHN_BITSHIFTSIZE, shn, rw, &shn->bitshift))
+                {
+                    sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                    return(retval);
+                } /* if */
+                break;
+
+            case SHN_FN_VERBATIM:
+            default:
+                Sound_SetError("SHN: Unhandled function.");
+                sample->flags |= SOUND_SAMPLEFLAG_ERROR;
+                return(retval);
+        } /* switch */
+    } /* while */
 
     return(retval);
 } /* SHN_read */