static int
NextInt(IOSTREAM *fstream)
{ int ch;
int value = 0;
int gotone = 0;
int done = 0;
/* loop, accumulate hex value until find delimiter */
/* skip any initial delimiters found in read stream */
while (!done)
{ if ( Sfeof(fstream) )
{ value = -1;
done++;
} else
{ int dvalue;
ch = Sgetc(fstream) & 0xff;
if ( ch == '\r' )
continue;
dvalue = hexTable[ch];
if ( dvalue >= 0 )
{ value = (value << 4) + dvalue;
gotone++;
} else if ((hexTable[ch]) == -1 && gotone)
done++;
}
}
return value;
}
static ssize_t
ar_read(struct archive *a, void *cdata, const void **buffer)
{ archive_wrapper *ar = cdata;
if ( Sfeof(ar->data) )
{ return 0;
} else
{ ssize_t bytes = ar->data->limitp - ar->data->bufp;
*buffer = ar->data->bufp;
ar->data->bufp = ar->data->limitp;
ar->data->position->byteno += bytes;
return bytes;
}
}
XImage *
read_ppm_file(Display *disp, Colormap cmap, int depth, IOSTREAM *fd)
{ XImage *img;
long here = Stell(fd);
int c;
int fmt, encoding;
int width, height, bytes_per_line, scale=0;
char *data;
int allocdepth;
int pad = XBitmapPad(disp);
Visual *v = DefaultVisual(disp, DefaultScreen(disp));
ncolours = nmapped = nfailed = 0; /* statistics */
assert(pad%8 == 0);
if ( (c=Sgetc(fd)) != 'P' )
{ Sungetc(c, fd);
return NULL;
}
if ( !cmap )
cmap = DefaultColormap(disp, DefaultScreen(disp));
c = Sgetc(fd);
if ( c < '1' || c > '9' )
goto errout;
c -= '0';
fmt = ((c - 1) % 3) + 1;
encoding = c - fmt;
width = getNum(fd);
height = getNum(fd);
if ( fmt == PNM_PBM )
{ depth = 1;
} else
{ scale = getNum(fd);
if ( !depth )
depth = DefaultDepth(disp, DefaultScreen(disp));
}
if ( width < 0 || height < 0 || scale < 0 )
goto errout;
allocdepth = (depth >= 24 ? 32 : depth);
bytes_per_line = roundup((width*allocdepth+7)/8, pad/8);
data = (char *)pceMalloc(height * bytes_per_line);
img = XCreateImage(disp,
v,
depth,
fmt == PNM_PBM ? XYBitmap : ZPixmap,
0,
data,
width, height,
pad, bytes_per_line);
if ( !img )
{ perror("XCreateImage");
pceFree(data);
goto errout;
}
img->bits_per_pixel = depth;
switch(encoding)
{ int x, y;
case PNM_ASCII:
{ switch(fmt)
{ case PNM_PBM:
for(y=0; y<height; y++)
{ for(x=0; x<width; x++)
{ int value = getNum(fd);
if ( value < 0 || value > 1 )
goto errout;
XPutPixel(img, x, y, value);
}
}
break;
case PNM_PGM:
{ Table t = newTable(64);
for(y=0; y<height; y++)
{ for(x=0; x<width; x++)
{ int g = getNum(fd);
unsigned long pixel;
if ( g < 0 || g > scale )
goto errout;
if ( scale != 255 )
g = rescale(g, scale, 255);
pixel = colourPixel(disp, depth, cmap, t, g, g, g);
XPutPixel(img, x, y, pixel);
}
}
freeTable(t);
break;
}
case PNM_PPM:
{ Table t = newTable(64);
for(y=0; y<height; y++)
{ for(x=0; x<width; x++)
{ int r = getNum(fd);
int g = getNum(fd);
int b = getNum(fd);
unsigned long pixel;
if ( r < 0 || r > scale ||
g < 0 || g > scale ||
b < 0 || b > scale )
goto errout;
if ( scale != 255 )
{ r = rescale(r, scale, 255);
g = rescale(g, scale, 255);
b = rescale(b, scale, 255);
}
pixel = colourPixel(disp, depth, cmap, t, r, g, b);
XPutPixel(img, x, y, pixel);
}
}
freeTable(t);
break;
}
break;
}
break;
}
case PNM_RAWBITS:
{ switch(fmt)
{ case PNM_PBM:
{ int byte = 0;
int bit = 0;
for(y=0; y<height; y++)
{ for(x=0; x<width; x++)
{ if ( !bit )
{ byte = Sgetc(fd);
bit = 8;
}
bit--;
XPutPixel(img, x, y, (byte & (1<<bit)) ? 1 : 0);
}
bit = 0; /* scanlines are byte-aligned */
}
break;
}
case PNM_PGM:
{ Table t = newTable(64);
for(y=0; y<height; y++)
{ for(x=0; x<width; x++)
{ int g;
unsigned long pixel;
if ( Sfeof(fd) || (g=Sgetc(fd)) > scale )
goto errout;
if ( scale != 255 )
g = rescale(g, scale, 255);
pixel = colourPixel(disp, depth, cmap, t, g, g, g);
XPutPixel(img, x, y, pixel);
}
}
freeTable(t);
break;
}
case PNM_PPM:
{ Table t = newTable(64);
for(y=0; y<height; y++)
{ for(x=0; x<width; x++)
{ int r, g, b;
unsigned long pixel;
if ( Sfeof(fd) ||
(r=Sgetc(fd)) > scale ||
(g=Sgetc(fd)) > scale ||
(b=Sgetc(fd)) > scale )
goto errout;
if ( scale != 255 )
{ r = rescale(r, scale, 255);
g = rescale(g, scale, 255);
b = rescale(b, scale, 255);
}
pixel = colourPixel(disp, depth, cmap, t, r, g, b);
XPutPixel(img, x, y, pixel);
}
}
freeTable(t);
break;
}
break;
}
break;
}
case PNM_RUNLEN:
{ int rlen = 0;
unsigned long cpixel = NOPIXEL;
switch(fmt)
{ case PNM_PGM:
{ Table t = newTable(64);
DEBUG(NAME_pnm, Cprintf("Reading runlength encoded graymap\n"));
for(y=0; y<height; y++)
{ for(x=0; x<width; x++)
{ if ( rlen-- > 0 )
{ XPutPixel(img, x, y, cpixel);
} else
{ int g;
if ( (g=Sgetc(fd)) > scale ||
(rlen = Sgetc(fd)) == EOF )
goto errout;
rlen &= 0xff;
if ( scale != 255 )
g = rescale(g, scale, 255);
cpixel = colourPixel(disp, depth, cmap, t, g, g, g);
XPutPixel(img, x, y, cpixel);
rlen--;
}
}
}
freeTable(t);
break;
}
case PNM_PPM:
{ Table t = newTable(64);
for(y=0; y<height; y++)
{ for(x=0; x<width; x++)
{ if ( rlen-- > 0 )
{ XPutPixel(img, x, y, cpixel);
} else
{ int r, g, b;
if ( (r=Sgetc(fd)) > scale ||
(g=Sgetc(fd)) > scale ||
(b=Sgetc(fd)) > scale ||
(rlen = Sgetc(fd)) == EOF )
goto errout;
rlen &= 0xff;
if ( scale != 255 )
{ r = rescale(r, scale, 255);
g = rescale(g, scale, 255);
b = rescale(b, scale, 255);
}
cpixel = colourPixel(disp, depth, cmap, t, r, g, b);
XPutPixel(img, x, y, cpixel);
rlen--;
}
}
}
freeTable(t);
break;
}
}
}
}
DEBUG(NAME_ppm,
Cprintf("PNM: Converted %dx%dx%d image, %d colours (%d mapped, %d failed)\n",
width, height, depth, ncolours, nmapped, nfailed));
return img;
errout:
DEBUG(NAME_ppm,
Cprintf("PNM: Format error, index = %d\n", Stell(fd)));
Sseek(fd, here, SEEK_SET);
return NULL;
}
