bbits.c (2101B)
1 #include <u.h> 2 #include <libc.h> 3 #include <libg.h> 4 #include <bio.h> 5 #include "hdr.h" 6 7 enum { 8 Charsperfont = 157, 9 Void1b = (0xC6-0xA2)*Charsperfont+0x3f, 10 Void1e = (0xC9-0xA2)*Charsperfont - 1 11 }; 12 13 Bitmap * 14 breadbits(char *file, int n, long *chars, int size, uchar *bits, int **doneptr) 15 { 16 Bitmap *bm; 17 Biobuf *bf; 18 int i, j, byt; 19 int nch; 20 long c; 21 uchar *b, *nbits; 22 int *done; 23 static uchar missing[32] = {0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x08, 0x00, 0x04, 0x00, 0x02, 0x00, 0x01, 0x00, 0x00, 0x80, 0x00, 0x40, 0x00, 0x20, 0x00, 0x10, 0x00, 0x08, 0x00, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 24 uchar buf[32]; 25 26 bf = Bopen(file, OREAD); 27 if(bf == 0){ 28 fprint(2, "%s: %s: %r\n", argv0, file); 29 exits("bitfile open error"); 30 } 31 done = (int *)malloc(n*sizeof(done[0])); 32 if(done == 0){ 33 fprint(2, "%s: malloc error (%d bytes)\n", argv0, n); 34 exits("malloc error"); 35 } 36 *doneptr = done; 37 byt = size/8; 38 nch = 0; 39 for(i = 0; i < n; i++){ 40 done[i] = 1; 41 nch++; 42 c = chars[i]; 43 if((c >= Void1b) && (c <= Void1e)){ 44 done[i] = 0; 45 nch--; 46 continue; 47 } 48 /* magic via presotto for calculating the seek */ 49 j = c; 50 if(c >= 2*Charsperfont) 51 j += 294; /* baffling hole between A3 and A4 */ 52 if(c > Void1e) 53 j -= 3*Charsperfont - 0x3F; 54 j *= byt*size; /* bytes per char */ 55 j += 256; /* 256 front matter */ 56 Bseek(bf, j, 0); 57 Bread(bf, buf, sizeof(missing)); 58 if(memcmp(buf, missing, sizeof(missing)) == 0){ 59 done[i] = 0; 60 nch--; 61 continue; 62 } 63 Bseek(bf, j, 0); 64 b = bits + i*byt; 65 for(j = 0; j < size; j++){ /* rows */ 66 Bread(bf, b, byt); 67 b += n*byt; 68 } 69 } 70 nbits = (uchar *)malloc(nch*byt*size); 71 if(nbits == 0){ 72 fprint(2, "%s: malloc error (%d bytes)\n", argv0, nch*byt); 73 exits("malloc error"); 74 } 75 c = 0; 76 for(i = 0; i < n; i++) 77 if(done[i]){ 78 for(j = 0; j < size; j++) 79 memmove(nbits+c*byt+j*nch*byt, bits+i*byt+j*n*byt, byt); 80 c++; 81 } 82 bm = balloc((Rectangle){(Point){0, 0}, (Point){nch*size, size}}, 0); 83 if(bm == 0){ 84 fprint(2, "%s: balloc failure\n", argv0); 85 exits("balloc failure"); 86 } 87 wrbitmap(bm, 0, size, nbits); 88 return(bm); 89 }