Subversion Repositories planix.SVN

#include <u.h>
#include <libc.h>
#include <draw.h>

Image *
creadimage(Display *d, int fd, int dolock)
{
        char hdr[5*12+1];
        Rectangle r;
        int m, nb, miny, maxy, new, ldepth, ncblock;
        uchar *buf, *a;
        Image *i;
        ulong chan;

        if(readn(fd, hdr, 5*12) != 5*12)
                return nil;

        /*
         * distinguish new channel descriptor from old ldepth.
         * channel descriptors have letters as well as numbers,
         * while ldepths are a single digit formatted as %-11d.
         */
        new = 0;
        for(m=0; m<10; m++){
                if(hdr[m] != ' '){
                        new = 1;
                        break;
                }
        }
        if(hdr[11] != ' '){
                werrstr("creadimage: bad format");
                return nil;
        }
        if(new){
                hdr[11] = '\0';
                if((chan = strtochan(hdr)) == 0){
                        werrstr("creadimage: bad channel string %s", hdr);
                        return nil;
                }
        }else{
                ldepth = ((int)hdr[10])-'0';
                if(ldepth<0 || ldepth>3){
                        werrstr("creadimage: bad ldepth %d", ldepth);
                        return nil;
                }
                chan = drawld2chan[ldepth];
        }
        r.min.x=atoi(hdr+1*12);
        r.min.y=atoi(hdr+2*12);
        r.max.x=atoi(hdr+3*12);
        r.max.y=atoi(hdr+4*12);
        if(r.min.x>r.max.x || r.min.y>r.max.y){
                werrstr("creadimage: bad rectangle");
                return nil;
        }

        if(d){
                if(dolock)
                        lockdisplay(d);
                i = allocimage(d, r, chan, 0, 0);
                setmalloctag(i, getcallerpc(&d));
                if(dolock)
                        unlockdisplay(d);
                if(i == nil)
                        return nil;
        }else{
                i = mallocz(sizeof(Image), 1);
                if(i == nil)
                        return nil;
        }
        ncblock = _compblocksize(r, chantodepth(chan));
        buf = malloc(ncblock);
        if(buf == nil)
                goto Errout;
        miny = r.min.y;
        while(miny != r.max.y){
                if(readn(fd, hdr, 2*12) != 2*12){
                Errout:
                        if(dolock)
                                lockdisplay(d);
                Erroutlock:
                        freeimage(i);
                        if(dolock)
                                unlockdisplay(d);
                        free(buf);
                        return nil;
                }
                maxy = atoi(hdr+0*12);
                nb = atoi(hdr+1*12);
                if(maxy<=miny || r.max.y<maxy){
                        werrstr("creadimage: bad maxy %d", maxy);
                        goto Errout;
                }
                if(nb<=0 || ncblock<nb){
                        werrstr("creadimage: bad count %d", nb);
                        goto Errout;
                }
                if(readn(fd, buf, nb)!=nb)
                        goto Errout;
                if(d){
                        if(dolock)
                                lockdisplay(d);
                        a = bufimage(i->display, 21+nb);
                        if(a == nil)
                                goto Erroutlock;
                        a[0] = 'Y';
                        BPLONG(a+1, i->id);
                        BPLONG(a+5, r.min.x);
                        BPLONG(a+9, miny);
                        BPLONG(a+13, r.max.x);
                        BPLONG(a+17, maxy);
                        if(!new)        /* old image: flip the data bits */
                                _twiddlecompressed(buf, nb);
                        memmove(a+21, buf, nb);
                        if(dolock)
                                unlockdisplay(d);
                }
                miny = maxy;
        }
        free(buf);
        return i;
}