| /* |
| * Copyright 1996 by Jutta Degener and Carsten Bormann, Technische |
| * Universitaet Berlin. See the accompanying file "COPYRIGHT" for |
| * details. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE. |
| */ |
| |
| /*$Header*/ |
| |
| /* Generate code to pack a bit array from a name:#bits description, |
| * WAV #49 style. |
| */ |
| |
| #include <stdio.h> |
| #include "taste.h" |
| #include "proto.h" |
| #include <limits.h> |
| |
| /* This module goes back to one Jeff Chilton used for his implementation |
| * of the #49 WAV GSM format. (In his original patch 8, it replaced |
| * bitter.c.) |
| * |
| * In Microsoft's WAV #49 version of the GSM format, two 32 1/2 |
| * byte GSM frames are packed together to make one WAV frame, and |
| * the GSM parameters are packed into bytes right-to-left rather |
| * than left-to-right. |
| * |
| * That is, where toast's GSM format writes |
| * |
| * aaaaaabb bbbbcccc cdddddee ... |
| * ___1____ ___2____ ___3____ |
| * |
| * for parameters a (6 bits), b (6 bits), c (5 bits), d (5 bits), e .. |
| * the WAV format has |
| * |
| * bbaaaaaa ccccbbbb eedddddc ... |
| * ___1____ ___2____ ___3____ |
| * |
| * (This format looks a lot prettier if one pictures octets coming |
| * in through a fifo queue from the left, rather than waiting in the |
| * right-hand remainder of a C array.) |
| */ |
| |
| #define WORD_BITS 16 /* sizeof(uword) * CHAR_BIT on the |
| * target architecture---if this isn't 16, |
| * you're in trouble with this library anyway. |
| */ |
| |
| #define BYTE_BITS 8 /* CHAR_BIT on the target architecture--- |
| * if this isn't 8, you're in *deep* trouble. |
| */ |
| |
| void write_code P2((s_spex, n_spex), struct spex * s_spex, int n_spex) |
| { |
| struct spex * sp = s_spex; |
| int n_in = 0; |
| |
| printf("uword sr = 0;\n"); |
| |
| for (; n_spex > 0; n_spex--, sp++) { |
| |
| /* insert old |
| * new var value unused |
| * here |
| * |
| * [____________xxxxxx**********] |
| * |
| * <----- n_in ------> |
| */ |
| printf("sr = sr >> %d | %s << %d;\n", |
| sp->varsize, |
| sp->var, |
| WORD_BITS - sp->varsize); |
| |
| n_in += sp->varsize; |
| |
| while (n_in >= BYTE_BITS) { |
| printf("*c++ = sr >> %d;\n", |
| WORD_BITS - n_in); |
| n_in -= BYTE_BITS; |
| } |
| } |
| |
| while (n_in >= BYTE_BITS) { |
| printf("*c++ = sr >> %d;\n", WORD_BITS - n_in); |
| n_in -= BYTE_BITS; |
| } |
| |
| if (n_in > 0) { |
| fprintf(stderr, "warning: %d bits left over\n", n_in); |
| } |
| } |