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1 #include <u.h>2 #include <libc.h>3 #include <draw.h>4 #include <memdraw.h>6 int7 _cloadmemimage(Memimage *i, Rectangle r, uchar *data, int ndata)8 {9 int y, bpl, c, cnt, offs;10 uchar mem[NMEM], *memp, *omemp, *emem, *linep, *elinep, *u, *eu;12 if(!rectinrect(r, i->r))13 return -1;14 bpl = bytesperline(r, i->depth);15 u = data;16 eu = data+ndata;17 memp = mem;18 emem = mem+NMEM;19 y = r.min.y;20 linep = byteaddr(i, Pt(r.min.x, y));21 elinep = linep+bpl;22 for(;;){23 if(linep == elinep){24 if(++y == r.max.y)25 break;26 linep = byteaddr(i, Pt(r.min.x, y));27 elinep = linep+bpl;28 }29 if(u == eu){ /* buffer too small */30 return -1;31 }32 c = *u++;33 if(c >= 128){34 for(cnt=c-128+1; cnt!=0 ;--cnt){35 if(u == eu){ /* buffer too small */36 return -1;37 }38 if(linep == elinep){ /* phase error */39 return -1;40 }41 *linep++ = *u;42 *memp++ = *u++;43 if(memp == emem)44 memp = mem;45 }46 }47 else{48 if(u == eu) /* short buffer */49 return -1;50 offs = *u++ + ((c&3)<<8)+1;51 if(memp-mem < offs)52 omemp = memp+(NMEM-offs);53 else54 omemp = memp-offs;55 for(cnt=(c>>2)+NMATCH; cnt!=0; --cnt){56 if(linep == elinep) /* phase error */57 return -1;58 *linep++ = *omemp;59 *memp++ = *omemp++;60 if(omemp == emem)61 omemp = mem;62 if(memp == emem)63 memp = mem;64 }65 }66 }67 return u-data;68 }