#include <assert.h>
#include <errno.h>
-#include "lbx.h"
#include "byteorder.h"
+#include "misc.h"
+#include "lbx.h"
+#include "image.h"
struct lbx_image {
- FILE *f;
uint16_t width, height;
- uint16_t wtf1, wtf2;
+ uint16_t wtf1;
uint16_t offs, frames;
+ uint16_t pal;
+
+ FILE *f;
+ long foff;
+
+ int currentframe;
+ int currentx, currenty;
+ unsigned char **framedata;
+
uint32_t offsets[];
};
struct lbx_image *lbximg_fopen(FILE *f)
{
- struct lbx_image tmp = {.f = f}, *new;
+ struct lbx_image tmp = {.f = f}, *new = NULL;
if (fread(&tmp.width, sizeof tmp.width, 1, f) != 1) goto readerr;
if (fread(&tmp.height, sizeof tmp.height, 1, f) != 1) goto readerr;
if (fread(&tmp.wtf1, sizeof tmp.wtf1, 1, f) != 1) goto readerr;
if (fread(&tmp.offs, sizeof tmp.offs, 1, f) != 1) goto readerr;
if (fread(&tmp.frames, sizeof tmp.frames, 1, f) != 1) goto readerr;
- if (fread(&tmp.wtf2, sizeof tmp.wtf2, 1, f) != 1) goto readerr;
+ if (fread(&tmp.pal, sizeof tmp.pal, 1, f) != 1) goto readerr;
+
+ tmp.width = letohs(tmp.width); tmp.foff += sizeof tmp.width;
+ tmp.height = letohs(tmp.height); tmp.foff += sizeof tmp.height;
+ tmp.wtf1 = letohs(tmp.wtf1); tmp.foff += sizeof tmp.wtf1;
+ tmp.offs = letohs(tmp.offs); tmp.foff += sizeof tmp.offs;
+ tmp.frames = letohs(tmp.frames); tmp.foff += sizeof tmp.frames;
+ tmp.pal = letohs(tmp.pal); tmp.foff += sizeof tmp.pal;
+
+ /* For some reason, the format seems to need this. */
+ tmp.offs++;
+ tmp.frames++;
- tmp.width = letohs(tmp.width);
- tmp.height = letohs(tmp.height);
- tmp.wtf1 = letohs(tmp.wtf1);
- tmp.offs = letohs(tmp.offs);
- tmp.frames = letohs(tmp.frames);
- tmp.wtf2 = letohs(tmp.wtf2);
+ /* Format constraints. */
+ if (tmp.offs <= tmp.frames) {
+ lbx_errno = LBX_EFORMAT;
+ return NULL;
+ }
/*
* DEBUG ONLY. These assertions exist to catch otherwise valid image
* If we never find any exceptions, we can replace the assertions with
* assumptions.
*/
- assert(tmp.wtf1 == 0);
- assert(tmp.offs == tmp.frames + 1);
+ _lbx_assert(tmp.wtf1 == 0);
+ _lbx_assert(tmp.offs == tmp.frames + 1);
+ _lbx_assert(tmp.pal == 0 || tmp.pal == 0x1000);
new = malloc(sizeof *new + tmp.offs * sizeof *new->offsets);
if (!new) {
}
*new = tmp;
+ new->currentframe = -1;
- if (fread(new->offsets, sizeof *new->offsets, new->offs, f) != new->offs)
+ if (fread(new->offsets, sizeof *new->offsets, new->offs, f)!= new->offs)
goto readerr;
+ new->foff += sizeof *new->offsets * new->offs;
return new;
readerr:
return NULL;
}
+static int _lbx_drawrow(int first, struct lbx_image *img)
+{
+ uint16_t type, yval, count, xval;
+ unsigned char *pos;
+ unsigned char abyss;
+ size_t rc;
+
+ assert(img->framedata);
+
+ if (fread(&type, sizeof type, 1, img->f) != 1) goto readerr;
+ type = letohs(type); img->foff += sizeof type;
+
+ if (first) {
+ img->currentx = 0;
+ img->currenty = 0;
+ type = 0;
+ }
+
+ if (type == 0) {
+ if (fread(&yval, sizeof yval, 1, img->f) != 1) goto readerr;
+ yval = letohs(yval); img->foff += sizeof yval;
+ if (yval == 1000)
+ return 1;
+ if (fread(&count, sizeof count, 1, img->f) != 1) goto readerr;
+ count = letohs(count); img->foff += sizeof count;
+ if (fread(&xval, sizeof xval, 1, img->f) != 1) goto readerr;
+ xval = letohs(xval); img->foff += sizeof xval;
+ if (xval == 1000)
+ return 1;
+
+ /* Ensure that the row fits in the image. */
+ if (img->height - img->currenty <= yval || xval >= img->width) {
+ lbx_errno = LBX_EFORMAT;
+ return -1;
+ }
+
+ img->currenty += yval;
+ img->currentx = xval;
+ } else {
+ if (fread(&xval, sizeof xval, 1, img->f) != 1) goto readerr;
+ xval = letohs(xval); img->foff += sizeof xval;
+
+ if (img->width - img->currentx <= xval) {
+ lbx_errno = LBX_EFORMAT;
+ return -1;
+ }
+ img->currentx += xval;
+
+ count = type;
+
+ }
+
+ if (count > img->width - img->currentx) {
+ lbx_errno = LBX_EFORMAT;
+ return -1;
+ }
+
+ pos = &img->framedata[img->currenty][img->currentx];
+ rc = fread(pos, 1, count, img->f);
+ img->currentx += rc;
+ img->foff += rc;
+
+ if (rc < count)
+ goto readerr;
+
+ if (count % 2) {
+ if (fread(&abyss, 1, 1, img->f) != 1)
+ goto readerr;
+ img->foff += 1;
+ }
+
+ return 0;
+readerr:
+ if (feof(img->f)) {
+ lbx_errno = LBX_EEOF;
+ } else {
+ lbx_errno = -errno;
+ }
+ return -1;
+}
+
+unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
+{
+ if (frame >= img->frames || frame < 0) {
+ lbx_errno = LBX_ERANGE;
+ return NULL;
+ }
+
+ if (!img->framedata) {
+ unsigned char *tmp;
+ int i;
+
+ tmp = malloc(img->width * img->height);
+ if (!tmp) {
+ lbx_errno = -errno;
+ return NULL;
+ }
+
+ img->framedata = malloc(img->height * sizeof *img->framedata);
+ if (!img->framedata) {
+ lbx_errno = -errno;
+ free(tmp);
+ return NULL;
+ }
+
+ for (i = 0; i < img->height; i++) {
+ img->framedata[i] = tmp + i * img->width;
+ }
+ }
+
+ /* Start over if we are backtracking. */
+ if (img->currentframe > frame)
+ img->currentframe == -1;
+
+ /* We must have previous frame decoded to continue. */
+ if (frame > img->currentframe + 1) {
+ if (!lbximg_getframe(img, frame-1))
+ return NULL;
+ }
+
+ if (img->currentframe != frame) {
+ int rc, first = 1;
+
+ if (_lbx_fseek(img->f, &img->foff, img->offsets[frame]) == -1)
+ return NULL;
+
+ do {
+ rc = _lbx_drawrow(first, img);
+ if (rc == -1)
+ return NULL;
+ first = 0;
+
+ if (!rc && img->foff > img->offsets[frame+1]) {
+ lbx_errno = LBX_EFORMAT;
+ return NULL;
+ }
+ } while (!rc);
+ }
+
+ img->currentframe = frame;
+ return img->framedata;
+}
+
+int lbximg_loadpalette(FILE *f, struct lbx_colour palette[static 256])
+{
+ uint8_t entry[4];
+ int i;
+
+ for (i = 0; i < 256; i++) {
+ if (fread(entry, sizeof entry, 1, f) != 1) {
+ lbx_errno = (feof(f)) ? LBX_EEOF : -errno;
+ return -1;
+ }
+
+ if (entry[0] != 1) {
+ lbx_errno = LBX_EFORMAT;
+ return -1;
+ }
+
+ palette[i] = (struct lbx_colour){
+ .red = entry[1] << 2,
+ .green = entry[2] << 2,
+ .blue = entry[3] << 2,
+ };
+ }
+
+ return 0;
+}
+
+int
+lbximg_getpalette(struct lbx_image *img, struct lbx_colour palette[static 256])
+{
+ size_t hdrlen = 6*(sizeof img->pal)+(img->offs)*(sizeof *img->offsets);
+ unsigned int i;
+ size_t rc;
+
+ uint16_t zero, count;
+ uint8_t entry[4];
+
+ /* Do nothing if the image doesn't have embedded palette data. */
+ if (img->pal == 0)
+ return 0;
+
+ /* Palette data is located right after the header. */
+ if (_lbx_fseek(img->f, &img->foff, hdrlen) == -1)
+ return -1;
+
+ /* Palette header */
+ if (fread(&zero, sizeof zero, 1, img->f) != 1) goto readerr;
+ if (fread(&count, sizeof count, 1, img->f) != 1) goto readerr;
+ zero = letohs(zero); img->foff += sizeof zero;
+ count = letohs(count); img->foff += sizeof count;
+
+ if (zero != 0 || count > 256) {
+ lbx_errno = LBX_EFORMAT;
+ return -1;
+ }
+
+ if (hdrlen + 2*(sizeof zero) + count*(sizeof entry) > img->offsets[0]) {
+ lbx_errno = LBX_EFORMAT;
+ return -1;
+ }
+
+ for (i = 0; i < count; i++) {
+ rc = fread(entry, 1, sizeof entry, img->f);
+ img->foff += rc;
+
+ if (rc < sizeof entry) {
+ goto readerr;
+ }
+
+ if (entry[0] != 0) {
+ lbx_errno = LBX_EFORMAT;
+ return -1;
+ }
+
+ palette[i] = (struct lbx_colour){
+ .red = entry[1] << 2,
+ .green = entry[2] << 2,
+ .blue = entry[3] << 2,
+ };
+ }
+
+ return 0;
+readerr:
+ lbx_errno = feof(img->f) ? LBX_EEOF : -errno;
+ return -1;
+}
+
+void lbximg_getinfo(struct lbx_image *img, struct lbx_imginfo *info)
+{
+ *info = (struct lbx_imginfo) {
+ .width = img->width,
+ .height = img->height,
+ .nframes = img->frames,
+ };
+}
+
void lbximg_close(struct lbx_image *img)
{
if (!img) return;
+ if (img->framedata) {
+ free(img->framedata[0]);
+ free(img->framedata);
+ }
+
if (img->f) {
fclose(img->f);
}
projects / liblbx.git / blobdiff