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    /*
    
    $Log$
    
    Revision 1.15  2004/06/26 03:50:14  markster
    Merge source cleanups (bug #1911)
    
    
    Revision 1.14  2003/02/12 13:59:15  matteo
    mer feb 12 14:56:57 CET 2003
    
    Revision 1.1.1.1  2003/02/12 13:59:15  matteo
    mer feb 12 14:56:57 CET 2003
    
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    Revision 1.2  2000/01/05 08:20:39  markster
    Some OSS fixes and a few lpc changes to make it actually work
    
     * Revision 1.2  1996/08/20  20:41:32  jaf
     * Removed all static local variables that were SAVE'd in the Fortran
     * code, and put them in struct lpc10_decoder_state that is passed as an
     * argument.
     *
     * Removed init function, since all initialization is now done in
     * init_lpc10_decoder_state().
     *
     * Revision 1.1  1996/08/19  22:30:49  jaf
     * Initial revision
     *
    
    */
    
    /*  -- translated by f2c (version 19951025).
       You must link the resulting object file with the libraries:
    	-lf2c -lm   (in that order)
    */
    
    #include "f2c.h"
    
    
    #ifdef P_R_O_T_O_T_Y_P_E_S
    extern integer random_(struct lpc10_decoder_state *st);
    #endif
    
    
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    /* ********************************************************************** */
    
    /* 	RANDOM Version 49 */
    
    /* $Log$
    
     * Revision 1.15  2004/06/26 03:50:14  markster
     * Merge source cleanups (bug #1911)
    
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     *
    
     * Revision 1.14  2003/02/12 13:59:15  matteo
     * mer feb 12 14:56:57 CET 2003
     *
     * Revision 1.1.1.1  2003/02/12 13:59:15  matteo
     * mer feb 12 14:56:57 CET 2003
     *
     * Revision 1.2  2000/01/05 08:20:39  markster
     * Some OSS fixes and a few lpc changes to make it actually work
     *
    
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     * Revision 1.2  1996/08/20  20:41:32  jaf
     * Removed all static local variables that were SAVE'd in the Fortran
     * code, and put them in struct lpc10_decoder_state that is passed as an
     * argument.
     *
     * Removed init function, since all initialization is now done in
     * init_lpc10_decoder_state().
     *
     * Revision 1.1  1996/08/19  22:30:49  jaf
     * Initial revision
     * */
    /* Revision 1.3  1996/03/20  16:13:54  jaf */
    /* Rearranged comments a little bit, and added comments explaining that */
    /* even though there is local state here, there is no need to create an */
    /* ENTRY for reinitializing it. */
    
    /* Revision 1.2  1996/03/14  22:25:29  jaf */
    /* Just rearranged the comments and local variable declarations a bit. */
    
    /* Revision 1.1  1996/02/07 14:49:01  jaf */
    /* Initial revision */
    
    
    /* ********************************************************************* */
    
    /*  Pseudo random number generator based on Knuth, Vol 2, p. 27. */
    
    /* Function Return: */
    /*  RANDOM - Integer variable, uniformly distributed over -32768 to 32767 */
    
    /* This subroutine maintains local state from one call to the next. */
    /* In the context of the LPC10 coder, there is no reason to reinitialize */
    /* this local state when switching between audio streams, because its */
    /* results are only used to generate noise for unvoiced frames. */
    
    integer random_(struct lpc10_decoder_state *st)
    {
        /* Initialized data */
    
        integer *j;
        integer *k;
        shortint *y;
    
        /* System generated locals */
        integer ret_val;
    
    /* 	Parameters/constants */
    /*       Local state */
    /*   The following is a 16 bit 2's complement addition, */
    /*   with overflow checking disabled */
    
        j = &(st->j);
        k = &(st->k);
        y = &(st->y[0]);
    
        y[*k - 1] += y[*j - 1];
        ret_val = y[*k - 1];
        --(*k);
        if (*k <= 0) {
    	*k = 5;
        }
        --(*j);
        if (*j <= 0) {
    	*j = 5;
        }
        return ret_val;
    } /* random_ */