1 #include "lib9.h"
2 #include "draw.h"
3 #include "kernel.h"
4
5 Image *
creadimage(Display * d,int fd,int dolock)6 creadimage(Display *d, int fd, int dolock)
7 {
8 char hdr[5*12+1];
9 Rectangle r;
10 int m, nb, miny, maxy, new, ldepth, ncblock;
11 uchar *buf, *a;
12 Image *i;
13 ulong chan;
14 int font;
15
16 font = dolock&2;
17 dolock &= 1;
18 if(libreadn(fd, hdr, 5*12) != 5*12)
19 return nil;
20
21 /*
22 * distinguish new channel descriptor from old ldepth.
23 * channel descriptors have letters as well as numbers,
24 * while ldepths are a single digit formatted as %-11d.
25 */
26 new = 0;
27 for(m=0; m<10; m++){
28 if(hdr[m] != ' '){
29 new = 1;
30 break;
31 }
32 }
33 if(hdr[11] != ' '){
34 kwerrstr("creadimage: bad format");
35 return nil;
36 }
37 if(new){
38 hdr[11] = '\0';
39 if((chan = strtochan(hdr)) == 0){
40 kwerrstr("creadimage: bad channel string %s", hdr);
41 return nil;
42 }
43 }else{
44 ldepth = ((int)hdr[10])-'0';
45 if(ldepth<0 || ldepth>3){
46 kwerrstr("creadimage: bad ldepth %d", ldepth);
47 return nil;
48 }
49 chan = drawld2chan[ldepth];
50 }
51 r.min.x=atoi(hdr+1*12);
52 r.min.y=atoi(hdr+2*12);
53 r.max.x=atoi(hdr+3*12);
54 r.max.y=atoi(hdr+4*12);
55 if(r.min.x>r.max.x || r.min.y>r.max.y){
56 kwerrstr("creadimage: bad rectangle");
57 return nil;
58 }
59
60 if(dolock)
61 dolock = lockdisplay(d);
62 i = allocimage(d, r, chan, 0, 0);
63 if(dolock)
64 unlockdisplay(d);
65 if(i == nil)
66 return nil;
67 ncblock = _compblocksize(r, i->depth);
68 buf = malloc(ncblock);
69 if(buf == nil)
70 goto Errout;
71 miny = r.min.y;
72 while(miny != r.max.y){
73 if(libreadn(fd, hdr, 2*12) != 2*12){
74 Errout:
75 if(dolock)
76 lockdisplay(d);
77 Erroutlock:
78 freeimage(i);
79 if(dolock)
80 unlockdisplay(d);
81 free(buf);
82 return nil;
83 }
84 maxy = atoi(hdr+0*12);
85 nb = atoi(hdr+1*12);
86 if(maxy<=miny || r.max.y<maxy){
87 kwerrstr("creadimage: bad maxy %d", maxy);
88 goto Errout;
89 }
90 if(nb<=0 || ncblock<nb){
91 kwerrstr("creadimage: bad count %d", nb);
92 goto Errout;
93 }
94 if(libreadn(fd, buf, nb)!=nb)
95 goto Errout;
96 if(dolock)
97 lockdisplay(d);
98 a = bufimage(i->display, 21+nb);
99 if(a == nil)
100 goto Erroutlock;
101 a[0] = 'Y';
102 BPLONG(a+1, i->id);
103 BPLONG(a+5, r.min.x);
104 BPLONG(a+9, miny);
105 BPLONG(a+13, r.max.x);
106 BPLONG(a+17, maxy);
107 if(!font&&!new) /* old image: flip the data bits */
108 _twiddlecompressed(buf, nb);
109 memmove(a+21, buf, nb);
110 if(dolock)
111 unlockdisplay(d);
112 miny = maxy;
113 }
114 free(buf);
115 return i;
116 }
117