Merge branch 'drop-the-bass'

external/kiss_fft/TIPS

+Speed:
+    * If you want to use multiple cores, then compile with -openmp or -fopenmp (see your compiler docs).
+	Realize that larger FFTs will reap more benefit than smaller FFTs. This generally uses more CPU time, but
+	less wall time.
+
+    * experiment with compiler flags
+        Special thanks to Oscar Lesta. He suggested some compiler flags 
+        for gcc that make a big difference. They shave 10-15% off
+        execution time on some systems.  Try some combination of:
+                -march=pentiumpro
+                -ffast-math
+                -fomit-frame-pointer
+
+    * If the input data has no imaginary component, use the kiss_fftr code under tools/.
+      Real ffts are roughly twice as fast as complex.
+
+    * If you can rearrange your code to do 4 FFTs in parallel and you are on a recent Intel or AMD machine,
+    then you might want to experiment with the USE_SIMD code.  See README.simd
+
+
+Reducing code size:
+    * remove some of the butterflies. There are currently butterflies optimized for radices
+        2,3,4,5.  It is worth mentioning that you can still use FFT sizes that contain 
+        other factors, they just won't be quite as fast.  You can decide for yourself 
+        whether to keep radix 2 or 4.  If you do some work in this area, let me 
+        know what you find.
+
+    * For platforms where ROM/code space is more plentiful than RAM,
+     consider creating a hardcoded kiss_fft_state. In other words, decide which 
+     FFT size(s) you want and make a structure with the correct factors and twiddles.
+
+    * Frank van der Hulst offered numerous suggestions for smaller code size and correct operation 
+    on embedded targets.  "I'm happy to help anyone who is trying to implement KISSFFT on a micro"
+
+    Some of these were rolled into the mainline code base:
+        - using long casts to promote intermediate results of short*short multiplication
+        - delaying allocation of buffers that are sometimes unused.
+    In some cases, it may be desirable to limit capability in order to better suit the target:
+        - predefining the twiddle tables for the desired fft size.  

external/kiss_fft/_kiss_fft_guts.h

+/*
+ *  Copyright (c) 2003-2010, Mark Borgerding. All rights reserved.
+ *  This file is part of KISS FFT - https://github.com/mborgerding/kissfft
+ *
+ *  SPDX-License-Identifier: BSD-3-Clause
+ *  See COPYING file for more information.
+ */
+
+/* kiss_fft.h
+   defines kiss_fft_scalar as either short or a float type
+   and defines
+   typedef struct { kiss_fft_scalar r; kiss_fft_scalar i; }kiss_fft_cpx; */
+#include "kiss_fft.h"
+#include <limits.h>
+
+#define MAXFACTORS 32
+/* e.g. an fft of length 128 has 4 factors 
+ as far as kissfft is concerned
+ 4*4*4*2
+ */
+
+struct kiss_fft_state{
+    int nfft;
+    int inverse;
+    int factors[2*MAXFACTORS];
+    kiss_fft_cpx twiddles[1];
+};
+
+/*
+  Explanation of macros dealing with complex math:
+
+   C_MUL(m,a,b)         : m = a*b
+   C_FIXDIV( c , div )  : if a fixed point impl., c /= div. noop otherwise
+   C_SUB( res, a,b)     : res = a - b
+   C_SUBFROM( res , a)  : res -= a
+   C_ADDTO( res , a)    : res += a
+ * */
+#ifdef FIXED_POINT
+#if (FIXED_POINT==32)
+# define FRACBITS 31
+# define SAMPPROD int64_t
+#define SAMP_MAX 2147483647
+#else
+# define FRACBITS 15
+# define SAMPPROD int32_t 
+#define SAMP_MAX 32767
+#endif
+
+#define SAMP_MIN -SAMP_MAX
+
+#if defined(CHECK_OVERFLOW)
+#  define CHECK_OVERFLOW_OP(a,op,b)  \
+	if ( (SAMPPROD)(a) op (SAMPPROD)(b) > SAMP_MAX || (SAMPPROD)(a) op (SAMPPROD)(b) < SAMP_MIN ) { \
+		fprintf(stderr,"WARNING:overflow @ " __FILE__ "(%d): (%d " #op" %d) = %ld\n",__LINE__,(a),(b),(SAMPPROD)(a) op (SAMPPROD)(b) );  }
+#endif
+
+
+#   define smul(a,b) ( (SAMPPROD)(a)*(b) )
+#   define sround( x )  (kiss_fft_scalar)( ( (x) + (1<<(FRACBITS-1)) ) >> FRACBITS )
+
+#   define S_MUL(a,b) sround( smul(a,b) )
+
+#   define C_MUL(m,a,b) \
+      do{ (m).r = sround( smul((a).r,(b).r) - smul((a).i,(b).i) ); \
+          (m).i = sround( smul((a).r,(b).i) + smul((a).i,(b).r) ); }while(0)
+
+#   define DIVSCALAR(x,k) \
+	(x) = sround( smul(  x, SAMP_MAX/k ) )
+
+#   define C_FIXDIV(c,div) \
+	do {    DIVSCALAR( (c).r , div);  \
+		DIVSCALAR( (c).i  , div); }while (0)
+
+#   define C_MULBYSCALAR( c, s ) \
+    do{ (c).r =  sround( smul( (c).r , s ) ) ;\
+        (c).i =  sround( smul( (c).i , s ) ) ; }while(0)
+
+#else  /* not FIXED_POINT*/
+
+#   define S_MUL(a,b) ( (a)*(b) )
+#define C_MUL(m,a,b) \
+    do{ (m).r = (a).r*(b).r - (a).i*(b).i;\
+        (m).i = (a).r*(b).i + (a).i*(b).r; }while(0)
+#   define C_FIXDIV(c,div) /* NOOP */
+#   define C_MULBYSCALAR( c, s ) \
+    do{ (c).r *= (s);\
+        (c).i *= (s); }while(0)
+#endif
+
+#ifndef CHECK_OVERFLOW_OP
+#  define CHECK_OVERFLOW_OP(a,op,b) /* noop */
+#endif
+
+#define  C_ADD( res, a,b)\
+    do { \
+	    CHECK_OVERFLOW_OP((a).r,+,(b).r)\
+	    CHECK_OVERFLOW_OP((a).i,+,(b).i)\
+	    (res).r=(a).r+(b).r;  (res).i=(a).i+(b).i; \
+    }while(0)
+#define  C_SUB( res, a,b)\
+    do { \
+	    CHECK_OVERFLOW_OP((a).r,-,(b).r)\
+	    CHECK_OVERFLOW_OP((a).i,-,(b).i)\
+	    (res).r=(a).r-(b).r;  (res).i=(a).i-(b).i; \
+    }while(0)
+#define C_ADDTO( res , a)\
+    do { \
+	    CHECK_OVERFLOW_OP((res).r,+,(a).r)\
+	    CHECK_OVERFLOW_OP((res).i,+,(a).i)\
+	    (res).r += (a).r;  (res).i += (a).i;\
+    }while(0)
+
+#define C_SUBFROM( res , a)\
+    do {\
+	    CHECK_OVERFLOW_OP((res).r,-,(a).r)\
+	    CHECK_OVERFLOW_OP((res).i,-,(a).i)\
+	    (res).r -= (a).r;  (res).i -= (a).i; \
+    }while(0)
+
+
+#ifdef FIXED_POINT
+#  define KISS_FFT_COS(phase)  floor(.5+SAMP_MAX * cos (phase))
+#  define KISS_FFT_SIN(phase)  floor(.5+SAMP_MAX * sin (phase))
+#  define HALF_OF(x) ((x)>>1)
+#elif defined(USE_SIMD)
+#  define KISS_FFT_COS(phase) _mm_set1_ps( cos(phase) )
+#  define KISS_FFT_SIN(phase) _mm_set1_ps( sin(phase) )
+#  define HALF_OF(x) ((x)*_mm_set1_ps(.5))
+#else
+#  define KISS_FFT_COS(phase) (kiss_fft_scalar) cos(phase)
+#  define KISS_FFT_SIN(phase) (kiss_fft_scalar) sin(phase)
+#  define HALF_OF(x) ((x)*.5)
+#endif
+
+#define  kf_cexp(x,phase) \
+	do{ \
+		(x)->r = KISS_FFT_COS(phase);\
+		(x)->i = KISS_FFT_SIN(phase);\
+	}while(0)
+
+
+/* a debugging function */
+#define pcpx(c)\
+    fprintf(stderr,"%g + %gi\n",(double)((c)->r),(double)((c)->i) )
+
+
+#ifdef KISS_FFT_USE_ALLOCA
+// define this to allow use of alloca instead of malloc for temporary buffers
+// Temporary buffers are used in two case: 
+// 1. FFT sizes that have "bad" factors. i.e. not 2,3 and 5
+// 2. "in-place" FFTs.  Notice the quotes, since kissfft does not really do an in-place transform.
+#include <alloca.h>
+#define  KISS_FFT_TMP_ALLOC(nbytes) alloca(nbytes)
+#define  KISS_FFT_TMP_FREE(ptr) 
+#else
+#define  KISS_FFT_TMP_ALLOC(nbytes) KISS_FFT_MALLOC(nbytes)
+#define  KISS_FFT_TMP_FREE(ptr) KISS_FFT_FREE(ptr)
+#endif

external/kiss_fft/kiss_fft.c

+/*
+ *  Copyright (c) 2003-2010, Mark Borgerding. All rights reserved.
+ *  This file is part of KISS FFT - https://github.com/mborgerding/kissfft
+ *
+ *  SPDX-License-Identifier: BSD-3-Clause
+ *  See COPYING file for more information.
+ */
+
+
+#include "_kiss_fft_guts.h"
+/* The guts header contains all the multiplication and addition macros that are defined for
+ fixed or floating point complex numbers.  It also delares the kf_ internal functions.
+ */
+
+static void kf_bfly2(
+        kiss_fft_cpx * Fout,
+        const size_t fstride,
+        const kiss_fft_cfg st,
+        int m
+        )
+{
+    kiss_fft_cpx * Fout2;
+    kiss_fft_cpx * tw1 = st->twiddles;
+    kiss_fft_cpx t;
+    Fout2 = Fout + m;
+    do{
+        C_FIXDIV(*Fout,2); C_FIXDIV(*Fout2,2);
+
+        C_MUL (t,  *Fout2 , *tw1);
+        tw1 += fstride;
+        C_SUB( *Fout2 ,  *Fout , t );
+        C_ADDTO( *Fout ,  t );
+        ++Fout2;
+        ++Fout;
+    }while (--m);
+}
+
+static void kf_bfly4(
+        kiss_fft_cpx * Fout,
+        const size_t fstride,
+        const kiss_fft_cfg st,
+        const size_t m
+        )
+{
+    kiss_fft_cpx *tw1,*tw2,*tw3;
+    kiss_fft_cpx scratch[6];
+    size_t k=m;
+    const size_t m2=2*m;
+    const size_t m3=3*m;
+
+
+    tw3 = tw2 = tw1 = st->twiddles;
+
+    do {
+        C_FIXDIV(*Fout,4); C_FIXDIV(Fout[m],4); C_FIXDIV(Fout[m2],4); C_FIXDIV(Fout[m3],4);
+
+        C_MUL(scratch[0],Fout[m] , *tw1 );
+        C_MUL(scratch[1],Fout[m2] , *tw2 );
+        C_MUL(scratch[2],Fout[m3] , *tw3 );
+
+        C_SUB( scratch[5] , *Fout, scratch[1] );
+        C_ADDTO(*Fout, scratch[1]);
+        C_ADD( scratch[3] , scratch[0] , scratch[2] );
+        C_SUB( scratch[4] , scratch[0] , scratch[2] );
+        C_SUB( Fout[m2], *Fout, scratch[3] );
+        tw1 += fstride;
+        tw2 += fstride*2;
+        tw3 += fstride*3;
+        C_ADDTO( *Fout , scratch[3] );
+
+        if(st->inverse) {
+            Fout[m].r = scratch[5].r - scratch[4].i;
+            Fout[m].i = scratch[5].i + scratch[4].r;
+            Fout[m3].r = scratch[5].r + scratch[4].i;
+            Fout[m3].i = scratch[5].i - scratch[4].r;
+        }else{
+            Fout[m].r = scratch[5].r + scratch[4].i;
+            Fout[m].i = scratch[5].i - scratch[4].r;
+            Fout[m3].r = scratch[5].r - scratch[4].i;
+            Fout[m3].i = scratch[5].i + scratch[4].r;
+        }
+        ++Fout;
+    }while(--k);
+}
+
+static void kf_bfly3(
+         kiss_fft_cpx * Fout,
+         const size_t fstride,
+         const kiss_fft_cfg st,
+         size_t m
+         )
+{
+     size_t k=m;
+     const size_t m2 = 2*m;
+     kiss_fft_cpx *tw1,*tw2;
+     kiss_fft_cpx scratch[5];
+     kiss_fft_cpx epi3;
+     epi3 = st->twiddles[fstride*m];
+
+     tw1=tw2=st->twiddles;
+
+     do{
+         C_FIXDIV(*Fout,3); C_FIXDIV(Fout[m],3); C_FIXDIV(Fout[m2],3);
+
+         C_MUL(scratch[1],Fout[m] , *tw1);
+         C_MUL(scratch[2],Fout[m2] , *tw2);
+
+         C_ADD(scratch[3],scratch[1],scratch[2]);
+         C_SUB(scratch[0],scratch[1],scratch[2]);
+         tw1 += fstride;
+         tw2 += fstride*2;
+
+         Fout[m].r = Fout->r - HALF_OF(scratch[3].r);
+         Fout[m].i = Fout->i - HALF_OF(scratch[3].i);
+
+         C_MULBYSCALAR( scratch[0] , epi3.i );
+
+         C_ADDTO(*Fout,scratch[3]);
+
+         Fout[m2].r = Fout[m].r + scratch[0].i;
+         Fout[m2].i = Fout[m].i - scratch[0].r;
+
+         Fout[m].r -= scratch[0].i;
+         Fout[m].i += scratch[0].r;
+
+         ++Fout;
+     }while(--k);
+}
+
+static void kf_bfly5(
+        kiss_fft_cpx * Fout,
+        const size_t fstride,
+        const kiss_fft_cfg st,
+        int m
+        )
+{
+    kiss_fft_cpx *Fout0,*Fout1,*Fout2,*Fout3,*Fout4;
+    int u;
+    kiss_fft_cpx scratch[13];
+    kiss_fft_cpx * twiddles = st->twiddles;
+    kiss_fft_cpx *tw;
+    kiss_fft_cpx ya,yb;
+    ya = twiddles[fstride*m];
+    yb = twiddles[fstride*2*m];
+
+    Fout0=Fout;
+    Fout1=Fout0+m;
+    Fout2=Fout0+2*m;
+    Fout3=Fout0+3*m;
+    Fout4=Fout0+4*m;
+
+    tw=st->twiddles;
+    for ( u=0; u<m; ++u ) {
+        C_FIXDIV( *Fout0,5); C_FIXDIV( *Fout1,5); C_FIXDIV( *Fout2,5); C_FIXDIV( *Fout3,5); C_FIXDIV( *Fout4,5);
+        scratch[0] = *Fout0;
+
+        C_MUL(scratch[1] ,*Fout1, tw[u*fstride]);
+        C_MUL(scratch[2] ,*Fout2, tw[2*u*fstride]);
+        C_MUL(scratch[3] ,*Fout3, tw[3*u*fstride]);
+        C_MUL(scratch[4] ,*Fout4, tw[4*u*fstride]);
+
+        C_ADD( scratch[7],scratch[1],scratch[4]);
+        C_SUB( scratch[10],scratch[1],scratch[4]);
+        C_ADD( scratch[8],scratch[2],scratch[3]);
+        C_SUB( scratch[9],scratch[2],scratch[3]);
+
+        Fout0->r += scratch[7].r + scratch[8].r;
+        Fout0->i += scratch[7].i + scratch[8].i;
+
+        scratch[5].r = scratch[0].r + S_MUL(scratch[7].r,ya.r) + S_MUL(scratch[8].r,yb.r);
+        scratch[5].i = scratch[0].i + S_MUL(scratch[7].i,ya.r) + S_MUL(scratch[8].i,yb.r);
+
+        scratch[6].r =  S_MUL(scratch[10].i,ya.i) + S_MUL(scratch[9].i,yb.i);
+        scratch[6].i = -S_MUL(scratch[10].r,ya.i) - S_MUL(scratch[9].r,yb.i);
+
+        C_SUB(*Fout1,scratch[5],scratch[6]);
+        C_ADD(*Fout4,scratch[5],scratch[6]);
+
+        scratch[11].r = scratch[0].r + S_MUL(scratch[7].r,yb.r) + S_MUL(scratch[8].r,ya.r);
+        scratch[11].i = scratch[0].i + S_MUL(scratch[7].i,yb.r) + S_MUL(scratch[8].i,ya.r);
+        scratch[12].r = - S_MUL(scratch[10].i,yb.i) + S_MUL(scratch[9].i,ya.i);
+        scratch[12].i = S_MUL(scratch[10].r,yb.i) - S_MUL(scratch[9].r,ya.i);
+
+        C_ADD(*Fout2,scratch[11],scratch[12]);
+        C_SUB(*Fout3,scratch[11],scratch[12]);
+
+        ++Fout0;++Fout1;++Fout2;++Fout3;++Fout4;
+    }
+}
+
+/* perform the butterfly for one stage of a mixed radix FFT */
+static void kf_bfly_generic(
+        kiss_fft_cpx * Fout,
+        const size_t fstride,
+        const kiss_fft_cfg st,
+        int m,
+        int p
+        )
+{
+    int u,k,q1,q;
+    kiss_fft_cpx * twiddles = st->twiddles;
+    kiss_fft_cpx t;
+    int Norig = st->nfft;
+
+    kiss_fft_cpx * scratch = (kiss_fft_cpx*)KISS_FFT_TMP_ALLOC(sizeof(kiss_fft_cpx)*p);
+
+    for ( u=0; u<m; ++u ) {
+        k=u;
+        for ( q1=0 ; q1<p ; ++q1 ) {
+            scratch[q1] = Fout[ k  ];
+            C_FIXDIV(scratch[q1],p);
+            k += m;
+        }
+
+        k=u;
+        for ( q1=0 ; q1<p ; ++q1 ) {
+            int twidx=0;
+            Fout[ k ] = scratch[0];
+            for (q=1;q<p;++q ) {
+                twidx += fstride * k;
+                if (twidx>=Norig) twidx-=Norig;
+                C_MUL(t,scratch[q] , twiddles[twidx] );
+                C_ADDTO( Fout[ k ] ,t);
+            }
+            k += m;
+        }
+    }
+    KISS_FFT_TMP_FREE(scratch);
+}
+
+static
+void kf_work(
+        kiss_fft_cpx * Fout,
+        const kiss_fft_cpx * f,
+        const size_t fstride,
+        int in_stride,
+        int * factors,
+        const kiss_fft_cfg st
+        )
+{
+    kiss_fft_cpx * Fout_beg=Fout;
+    const int p=*factors++; /* the radix  */
+    const int m=*factors++; /* stage's fft length/p */
+    const kiss_fft_cpx * Fout_end = Fout + p*m;
+
+#ifdef _OPENMP
+    // use openmp extensions at the 
+    // top-level (not recursive)
+    if (fstride==1 && p<=5)
+    {
+        int k;
+
+        // execute the p different work units in different threads
+#       pragma omp parallel for
+        for (k=0;k<p;++k) 
+            kf_work( Fout +k*m, f+ fstride*in_stride*k,fstride*p,in_stride,factors,st);
+        // all threads have joined by this point
+
+        switch (p) {
+            case 2: kf_bfly2(Fout,fstride,st,m); break;
+            case 3: kf_bfly3(Fout,fstride,st,m); break; 
+            case 4: kf_bfly4(Fout,fstride,st,m); break;
+            case 5: kf_bfly5(Fout,fstride,st,m); break; 
+            default: kf_bfly_generic(Fout,fstride,st,m,p); break;
+        }
+        return;
+    }
+#endif
+
+    if (m==1) {
+        do{
+            *Fout = *f;
+            f += fstride*in_stride;
+        }while(++Fout != Fout_end );
+    }else{
+        do{
+            // recursive call:
+            // DFT of size m*p performed by doing
+            // p instances of smaller DFTs of size m, 
+            // each one takes a decimated version of the input
+            kf_work( Fout , f, fstride*p, in_stride, factors,st);
+            f += fstride*in_stride;
+        }while( (Fout += m) != Fout_end );
+    }
+
+    Fout=Fout_beg;
+
+    // recombine the p smaller DFTs 
+    switch (p) {
+        case 2: kf_bfly2(Fout,fstride,st,m); break;
+        case 3: kf_bfly3(Fout,fstride,st,m); break; 
+        case 4: kf_bfly4(Fout,fstride,st,m); break;
+        case 5: kf_bfly5(Fout,fstride,st,m); break; 
+        default: kf_bfly_generic(Fout,fstride,st,m,p); break;
+    }
+}
+
+/*  facbuf is populated by p1,m1,p2,m2, ...
+    where 
+    p[i] * m[i] = m[i-1]
+    m0 = n                  */
+static 
+void kf_factor(int n,int * facbuf)
+{
+    int p=4;
+    double floor_sqrt;
+    floor_sqrt = floor( sqrt((double)n) );
+
+    /*factor out powers of 4, powers of 2, then any remaining primes */
+    do {
+        while (n % p) {
+            switch (p) {
+                case 4: p = 2; break;
+                case 2: p = 3; break;
+                default: p += 2; break;
+            }
+            if (p > floor_sqrt)
+                p = n;          /* no more factors, skip to end */
+        }
+        n /= p;
+        *facbuf++ = p;
+        *facbuf++ = n;
+    } while (n > 1);
+}
+
+/*
+ *
+ * User-callable function to allocate all necessary storage space for the fft.
+ *
+ * The return value is a contiguous block of memory, allocated with malloc.  As such,
+ * It can be freed with free(), rather than a kiss_fft-specific function.
+ * */
+kiss_fft_cfg kiss_fft_alloc(int nfft,int inverse_fft,void * mem,size_t * lenmem )
+{
+    kiss_fft_cfg st=NULL;
+    size_t memneeded = sizeof(struct kiss_fft_state)
+        + sizeof(kiss_fft_cpx)*(nfft-1); /* twiddle factors*/
+
+    if ( lenmem==NULL ) {
+        st = ( kiss_fft_cfg)KISS_FFT_MALLOC( memneeded );
+    }else{
+        if (mem != NULL && *lenmem >= memneeded)
+            st = (kiss_fft_cfg)mem;
+        *lenmem = memneeded;
+    }
+    if (st) {
+        int i;
+        st->nfft=nfft;
+        st->inverse = inverse_fft;
+
+        for (i=0;i<nfft;++i) {
+            const double pi=3.141592653589793238462643383279502884197169399375105820974944;
+            double phase = -2*pi*i / nfft;
+            if (st->inverse)
+                phase *= -1;
+            kf_cexp(st->twiddles+i, phase );
+        }
+
+        kf_factor(nfft,st->factors);
+    }
+    return st;
+}
+
+
+void kiss_fft_stride(kiss_fft_cfg st,const kiss_fft_cpx *fin,kiss_fft_cpx *fout,int in_stride)
+{
+    if (fin == fout) {
+        //NOTE: this is not really an in-place FFT algorithm.
+        //It just performs an out-of-place FFT into a temp buffer
+        kiss_fft_cpx * tmpbuf = (kiss_fft_cpx*)KISS_FFT_TMP_ALLOC( sizeof(kiss_fft_cpx)*st->nfft);
+        kf_work(tmpbuf,fin,1,in_stride, st->factors,st);
+        memcpy(fout,tmpbuf,sizeof(kiss_fft_cpx)*st->nfft);
+        KISS_FFT_TMP_FREE(tmpbuf);
+    }else{
+        kf_work( fout, fin, 1,in_stride, st->factors,st );
+    }
+}
+
+void kiss_fft(kiss_fft_cfg cfg,const kiss_fft_cpx *fin,kiss_fft_cpx *fout)
+{
+    kiss_fft_stride(cfg,fin,fout,1);
+}
+
+
+void kiss_fft_cleanup(void)
+{
+    // nothing needed any more
+}
+
+int kiss_fft_next_fast_size(int n)
+{
+    while(1) {
+        int m=n;
+        while ( (m%2) == 0 ) m/=2;
+        while ( (m%3) == 0 ) m/=3;
+        while ( (m%5) == 0 ) m/=5;
+        if (m<=1)
+            break; /* n is completely factorable by twos, threes, and fives */
+        n++;
+    }
+    return n;
+}

external/kiss_fft/kiss_fft.h

+/*
+ *  Copyright (c) 2003-2010, Mark Borgerding. All rights reserved.
+ *  This file is part of KISS FFT - https://github.com/mborgerding/kissfft
+ *
+ *  SPDX-License-Identifier: BSD-3-Clause
+ *  See COPYING file for more information.
+ */
+