* pcx.c *
***********************************************************/
+#include "pcx.h"
#include "image.h"
#include "misc.h"
+#define PCX_DEBUG FALSE
+
#define PCX_MAGIC 0x0a /* first byte in a PCX image file */
#define PCX_LAST_VERSION 5 /* last acceptable version number */
#define PCX_ENCODING 1 /* PCX encoding method */
unsigned char filler[58]; /* fill to struct size of 128 */
};
-static byte *PCX_ReadBitmap(Image *, byte *, byte *);
-static byte *PCX_ReadColormap(Image *, byte *, byte *);
+/* global PCX error value */
+int errno_pcx = PCX_Success;
+
+static byte *PCX_ReadBitmap(Image *image, byte *buffer_ptr, byte *buffer_last)
+{
+ /* Run Length Encoding: If the two high bits are set,
+ * then the low 6 bits contain a repeat count, and the byte to
+ * repeat is the next byte in the file. If the two high bits are
+ * not set, then this is the byte to write.
+ */
+
+ unsigned int bytes_per_pixel = (image->depth + 7) / 8;
+ register byte *bitmap_ptr, *bitmap_last;
+ register byte value, count;
+
+ bitmap_ptr = image->data;
+ bitmap_last = bitmap_ptr + (image->width * image->height * bytes_per_pixel);
+
+ while (bitmap_ptr < bitmap_last && buffer_ptr < buffer_last)
+ {
+ value = *buffer_ptr++;
+
+ if ((value & 0xc0) == 0xc0) /* this is a repeat count byte */
+ {
+ count = value & 0x3f; /* extract repeat count from byte */
+ value = *buffer_ptr++; /* next byte is value to repeat */
+
+ for (; count && bitmap_ptr < bitmap_last; count--)
+ *bitmap_ptr++ = value;
+
+ if (count) /* repeat count spans end of bitmap */
+ return NULL;
+ }
+ else
+ *bitmap_ptr++ = value;
+
+ image->rgb.color_used[value] = TRUE;
+ }
+
+ /* check if end of buffer was reached before end of bitmap */
+ if (bitmap_ptr < bitmap_last)
+ return NULL;
+
+ /* return current buffer position for next decoding function */
+ return buffer_ptr;
+}
+
+static byte *PCX_ReadColormap(Image *image,byte *buffer_ptr, byte *buffer_last)
+{
+ int i, magic;
+
+ /* read colormap magic byte */
+ magic = *buffer_ptr++;
+
+ /* check magic colormap header byte */
+ if (magic != PCX_256COLORS_MAGIC)
+ return NULL;
+
+ /* check if enough bytes left for a complete colormap */
+ if (buffer_ptr + PCX_COLORMAP_SIZE > buffer_last)
+ return NULL;
+
+ /* read 256 colors from PCX colormap */
+ for (i=0; i<PCX_MAXCOLORS; i++)
+ {
+ image->rgb.red[i] = *buffer_ptr++ << 8;
+ image->rgb.green[i] = *buffer_ptr++ << 8;
+ image->rgb.blue[i] = *buffer_ptr++ << 8;
+ }
+
+ /* return current buffer position for next decoding function */
+ return buffer_ptr;
+}
Image *Read_PCX_to_Image(char *filename)
{
int width, height, depth;
int i;
+ errno_pcx = PCX_Success;
+
if (!(file = fopen(filename, "r")))
+ {
+ errno_pcx = PCX_OpenFailed;
return NULL;
+ }
if (fseek(file, 0, SEEK_END) == -1)
{
fclose(file);
+ errno_pcx = PCX_ReadFailed;
return NULL;
}
file_length = ftell(file);
rewind(file);
- if (file_length < PCX_HEADER_SIZE + PCX_COLORMAP_SIZE)
+ if (file_length < PCX_HEADER_SIZE)
{
+ /* PCX file is too short to contain a valid PCX header */
fclose(file);
+
+ errno_pcx = PCX_FileInvalid;
return NULL;
}
if (fread(file_buffer, 1, file_length, file) != file_length)
{
fclose(file);
+ errno_pcx = PCX_ReadFailed;
return NULL;
}
width < 0 || height < 0)
{
free(file_buffer);
+
+ errno_pcx = PCX_FileInvalid;
return NULL;
}
+#if PCX_DEBUG
if (options.verbose)
{
printf("%s is a %dx%d PC Paintbrush image with %d bitplanes\n",
- filename, pcx.xmax, pcx.ymax,
+ filename, width, height,
pcx.color_planes);
printf("depth: %d\n", pcx.bits_per_pixel);
+ printf("color_planes: %d\n", pcx.color_planes);
printf("bytes_per_line: %d\n", pcx.bytes_per_line);
printf("palette type: %s\n",
(pcx.palette_type == 1 ? "color" :
pcx.palette_type == 2 ? "grayscale" : "undefined"));
}
+#endif
/* allocate new image structure */
image = newImage(width, height, depth);
{
free(file_buffer);
freeImage(image);
+
+ errno_pcx = PCX_FileInvalid;
+ return NULL;
+ }
+
+ if (file_length < PCX_HEADER_SIZE + PCX_COLORMAP_SIZE)
+ {
+ /* PCX file is too short to contain a valid 256 colors colormap */
+ fclose(file);
+ errno_pcx = PCX_ColorFailed;
return NULL;
}
{
free(file_buffer);
freeImage(image);
+ errno_pcx = PCX_ColorFailed;
return NULL;
}
if (image->rgb.color_used[i])
image->rgb.used++;
+#if PCX_DEBUG
if (options.verbose)
printf("Read_PCX_to_Image: %d colors found\n", image->rgb.used);
+#endif
return image;
}
-
-static byte *PCX_ReadBitmap(Image *image, byte *buffer_ptr, byte *buffer_last)
-{
- /* Run Length Encoding: If the two high bits are set,
- * then the low 6 bits contain a repeat count, and the byte to
- * repeat is the next byte in the file. If the two high bits are
- * not set, then this is the byte to write.
- */
-
- unsigned int bytes_per_pixel = (image->depth + 7) / 8;
- register byte *bitmap_ptr, *bitmap_last;
- register byte value, count;
-
- bitmap_ptr = image->data;
- bitmap_last = bitmap_ptr + (image->width * image->height * bytes_per_pixel);
-
- while (bitmap_ptr < bitmap_last && buffer_ptr < buffer_last)
- {
- value = *buffer_ptr++;
-
- if ((value & 0xc0) == 0xc0) /* this is a repeat count byte */
- {
- count = value & 0x3f; /* extract repeat count from byte */
- value = *buffer_ptr++; /* next byte is value to repeat */
-
- for (; count && bitmap_ptr < bitmap_last; count--)
- *bitmap_ptr++ = value;
-
- if (count) /* repeat count spans end of bitmap */
- return NULL;
- }
- else
- *bitmap_ptr++ = value;
-
- image->rgb.color_used[value] = TRUE;
- }
-
- /* check if end of buffer was reached before end of bitmap */
- if (bitmap_ptr < bitmap_last)
- return NULL;
-
- /* return current buffer position for next decoding function */
- return buffer_ptr;
-}
-
-static byte *PCX_ReadColormap(Image *image,byte *buffer_ptr, byte *buffer_last)
-{
- int i, magic;
-
- /* read colormap magic byte */
- magic = *buffer_ptr++;
-
- /* check magic colormap header byte */
- if (magic != PCX_256COLORS_MAGIC)
- return NULL;
-
- /* check if enough bytes left for a complete colormap */
- if (buffer_ptr + PCX_COLORMAP_SIZE > buffer_last)
- return NULL;
-
- /* read 256 colors from PCX colormap */
- for (i=0; i<PCX_MAXCOLORS; i++)
- {
- image->rgb.red[i] = *buffer_ptr++ << 8;
- image->rgb.green[i] = *buffer_ptr++ << 8;
- image->rgb.blue[i] = *buffer_ptr++ << 8;
- }
-
- /* return current buffer position for next decoding function */
- return buffer_ptr;
-}
projects / rocksndiamonds.git / blobdiff