#include <u.h>#include <libc.h>#include <bio.h>#include <thread.h>#define J40_CONFIRM_THAT_THIS_IS_EXPERIMENTAL_AND_POTENTIALLY_UNSAFE#define J40_IMPLEMENTATION#define J40_INLINEint __builtin_clz(unsigned int x);int __builtin_clzll(unsigned long long x);#include "j40.h" static voidusage(void){	fprint(2, "usage: %s\n", argv0);} static u8int *readall(int f, int *outsz){	int bufsz, sz, n;	u8int *s; 	bufsz = 65535;	s = nil;	for(sz = 0;; sz += n){		if(bufsz-sz < 65536){			bufsz *= 2;			s = realloc(s, bufsz);		}		if((n = readn(f, s+sz, bufsz-sz)) < 1)			break;	}	if(n < 0 || sz < 1){		if(n == 0)			werrstr("empty");		free(s);		return nil;	}	*outsz = sz; 	return s;} voidthreadmain(int argc, char **argv){	j40_pixels_u8x4 pixels;	u8int *p, *in, x;	j40_image image;	j40_frame frame;	int sz, y, n;	Biobuf *b; 	ARGBEGIN{	default:		usage();	}ARGEND 	if((in = readall(0, &sz)) == nil || (b = Bfdopen(1, OWRITE)) == nil)		sysfatal("%r");	j40_from_memory(&image, in, sz, free);	j40_output_format(&image, J40_RGBA, J40_U8X4); 	if(j40_next_frame(&image)){		frame = j40_current_frame(&image);		pixels = j40_frame_pixels_u8x4(&frame, J40_RGBA);		Bprint(b, "%11s %11d %11d %11d %11d ", "a8r8g8b8", 0, 0, pixels.width, pixels.height);		for(y = 0; y < pixels.height; ++y){			p = (u8int*)j40_row_u8x4(pixels, y);			for(n = 0; n < 4*pixels.width; n += 4){				x = p[n+0];				p[n+0] = p[n+2];				p[n+2] = x;			}			Bwrite(b, p, 4*pixels.width);		}	} 	if(j40_error(&image))		sysfatal("%s", j40_error_string(&image)); 	j40_free(&image);	Bterm(b); 	threadexitsall(nil);}