jpc_cs.c

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	uint_fast8_t tmp;
	poc->numpchgs = (cstate->numcomps > 256) ? (ms->len / 9) :
	  (ms->len / 7);
	if (!(poc->pchgs = jas_malloc(poc->numpchgs * sizeof(jpc_pocpchg_t)))) {
		goto error;
	}
	for (pchgno = 0, pchg = poc->pchgs; pchgno < poc->numpchgs; ++pchgno,
	  ++pchg) {
		if (jpc_getuint8(in, &pchg->rlvlnostart)) {
			goto error;
		}
		if (cstate->numcomps > 256) {
			if (jpc_getuint16(in, &pchg->compnostart)) {
				goto error;
			}
		} else {
			if (jpc_getuint8(in, &tmp)) {
				goto error;
			};
			pchg->compnostart = tmp;
		}
		if (jpc_getuint16(in, &pchg->lyrnoend) ||
		  jpc_getuint8(in, &pchg->rlvlnoend)) {
			goto error;
		}
		if (cstate->numcomps > 256) {
			if (jpc_getuint16(in, &pchg->compnoend)) {
				goto error;
			}
		} else {
			if (jpc_getuint8(in, &tmp)) {
				goto error;
			}
			pchg->compnoend = tmp;
		}
		if (jpc_getuint8(in, &pchg->prgord)) {
			goto error;
		}
		if (pchg->rlvlnostart > pchg->rlvlnoend ||
		  pchg->compnostart > pchg->compnoend) {
			goto error;
		}
	}
	return 0;

error:
	jpc_poc_destroyparms(ms);
	return -1;
}

static int jpc_poc_putparms(jpc_ms_t *ms, jpc_cstate_t *cstate, jas_stream_t *out)
{
	jpc_poc_t *poc = &ms->parms.poc;
	jpc_pocpchg_t *pchg;
	int pchgno;
	for (pchgno = 0, pchg = poc->pchgs; pchgno < poc->numpchgs; ++pchgno,
	  ++pchg) {
		if (jpc_putuint8(out, pchg->rlvlnostart) ||
		  ((cstate->numcomps > 256) ?
		  jpc_putuint16(out, pchg->compnostart) :
		  jpc_putuint8(out, pchg->compnostart)) ||
		  jpc_putuint16(out, pchg->lyrnoend) ||
		  jpc_putuint8(out, pchg->rlvlnoend) ||
		  ((cstate->numcomps > 256) ?
		  jpc_putuint16(out, pchg->compnoend) :
		  jpc_putuint8(out, pchg->compnoend)) ||
		  jpc_putuint8(out, pchg->prgord)) {
			return -1;
		}
	}
	return 0;
}

static int jpc_poc_dumpparms(jpc_ms_t *ms, FILE *out)
{
	jpc_poc_t *poc = &ms->parms.poc;
	jpc_pocpchg_t *pchg;
	int pchgno;
	for (pchgno = 0, pchg = poc->pchgs; pchgno < poc->numpchgs;
	  ++pchgno, ++pchg) {
		fprintf(out, "po[%d] = %d; ", pchgno, pchg->prgord);
		fprintf(out, "cs[%d] = %d; ce[%d] = %d; ",
		  pchgno, pchg->compnostart, pchgno, pchg->compnoend);
		fprintf(out, "rs[%d] = %d; re[%d] = %d; ",
		  pchgno, pchg->rlvlnostart, pchgno, pchg->rlvlnoend);
		fprintf(out, "le[%d] = %d\n", pchgno, pchg->lyrnoend);
	}
	return 0;
}

/******************************************************************************\
* CRG marker segment operations.
\******************************************************************************/

static void jpc_crg_destroyparms(jpc_ms_t *ms)
{
	jpc_crg_t *crg = &ms->parms.crg;
	if (crg->comps) {
		jas_free(crg->comps);
	}
}

static int jpc_crg_getparms(jpc_ms_t *ms, jpc_cstate_t *cstate, jas_stream_t *in)
{
	jpc_crg_t *crg = &ms->parms.crg;
	jpc_crgcomp_t *comp;
	uint_fast16_t compno;
	crg->numcomps = cstate->numcomps;
	if (!(crg->comps = jas_malloc(cstate->numcomps * sizeof(uint_fast16_t)))) {
		return -1;
	}
	for (compno = 0, comp = crg->comps; compno < cstate->numcomps;
	  ++compno, ++comp) {
		if (jpc_getuint16(in, &comp->hoff) ||
		  jpc_getuint16(in, &comp->voff)) {
			jpc_crg_destroyparms(ms);
			return -1;
		}
	}
	return 0;
}

static int jpc_crg_putparms(jpc_ms_t *ms, jpc_cstate_t *cstate, jas_stream_t *out)
{
	jpc_crg_t *crg = &ms->parms.crg;
	int compno;
	jpc_crgcomp_t *comp;

	/* Eliminate compiler warning about unused variables. */
	cstate = 0;

	for (compno = 0, comp = crg->comps; compno < crg->numcomps; ++compno,
	  ++comp) {
		if (jpc_putuint16(out, comp->hoff) ||
		  jpc_putuint16(out, comp->voff)) {
			return -1;
		}
	}
	return 0;
}

static int jpc_crg_dumpparms(jpc_ms_t *ms, FILE *out)
{
	jpc_crg_t *crg = &ms->parms.crg;
	int compno;
	jpc_crgcomp_t *comp;
	for (compno = 0, comp = crg->comps; compno < crg->numcomps; ++compno,
	  ++comp) {
		fprintf(out, "hoff[%d] = %d; voff[%d] = %d\n", compno,
		  comp->hoff, compno, comp->voff);
	}
	return 0;
}

/******************************************************************************\
* Operations for COM marker segment.
\******************************************************************************/

static void jpc_com_destroyparms(jpc_ms_t *ms)
{
	jpc_com_t *com = &ms->parms.com;
	if (com->data) {
		jas_free(com->data);
	}
}

static int jpc_com_getparms(jpc_ms_t *ms, jpc_cstate_t *cstate, jas_stream_t *in)
{
	jpc_com_t *com = &ms->parms.com;

	/* Eliminate compiler warning about unused variables. */
	cstate = 0;

	if (jpc_getuint16(in, &com->regid)) {
		return -1;
	}
	com->len = ms->len - 2;
	if (com->len > 0) {
		if (!(com->data = jas_malloc(com->len))) {
			return -1;
		}
		if (jas_stream_read(in, com->data, com->len) != JAS_CAST(int, com->len)) {
			return -1;
		}
	} else {
		com->data = 0;
	}
	return 0;
}

static int jpc_com_putparms(jpc_ms_t *ms, jpc_cstate_t *cstate, jas_stream_t *out)
{
	jpc_com_t *com = &ms->parms.com;

	/* Eliminate compiler warning about unused variables. */
	cstate = 0;

	if (jpc_putuint16(out, com->regid)) {
		return -1;
	}
	if (jas_stream_write(out, com->data, com->len) != JAS_CAST(int, com->len)) {
		return -1;
	}
	return 0;
}

static int jpc_com_dumpparms(jpc_ms_t *ms, FILE *out)
{
	jpc_com_t *com = &ms->parms.com;
	unsigned int i;
	int printable;
	fprintf(out, "regid = %d;\n", com->regid);
	printable = 1;
	for (i = 0; i < com->len; ++i) {
		if (!isprint(com->data[i])) {
			printable = 0;
			break;
		}
	}
	if (printable) {
		fprintf(out, "data = ");
		fwrite(com->data, sizeof(char), com->len, out);
		fprintf(out, "\n");
	}
	return 0;
}

/******************************************************************************\
* Operations for unknown types of marker segments.
\******************************************************************************/

static void jpc_unk_destroyparms(jpc_ms_t *ms)
{
	jpc_unk_t *unk = &ms->parms.unk;
	if (unk->data) {
		jas_free(unk->data);
	}
}

static int jpc_unk_getparms(jpc_ms_t *ms, jpc_cstate_t *cstate, jas_stream_t *in)
{
	jpc_unk_t *unk = &ms->parms.unk;

	/* Eliminate compiler warning about unused variables. */
	cstate = 0;

	if (ms->len > 0) {
		if (!(unk->data = jas_malloc(ms->len * sizeof(unsigned char)))) {
			return -1;
		}
		if (jas_stream_read(in, (char *) unk->data, ms->len) != JAS_CAST(int, ms->len)) {
			jas_free(unk->data);
			return -1;
		}
		unk->len = ms->len;
	} else {
		unk->data = 0;
		unk->len = 0;
	}
	return 0;
}

static int jpc_unk_putparms(jpc_ms_t *ms, jpc_cstate_t *cstate, jas_stream_t *out)
{
	/* Eliminate compiler warning about unused variables. */
	cstate = 0;
	ms = 0;
	out = 0;

	/* If this function is called, we are trying to write an unsupported
	  type of marker segment.  Return with an error indication.  */
	return -1;
}

static int jpc_unk_dumpparms(jpc_ms_t *ms, FILE *out)
{
	unsigned int i;
	jpc_unk_t *unk = &ms->parms.unk;
	for (i = 0; i < unk->len; ++i) {
		fprintf(out, "%02x ", unk->data[i]);
	}
	return 0;
}

/******************************************************************************\
* Primitive I/O operations.
\******************************************************************************/

int jpc_getuint8(jas_stream_t *in, uint_fast8_t *val)
{
	int c;
	if ((c = jas_stream_getc(in)) == EOF) {
		return -1;
	}
	if (val) {
		*val = c;
	}
	return 0;
}

int jpc_putuint8(jas_stream_t *out, uint_fast8_t val)
{
	if (jas_stream_putc(out, val & 0xff) == EOF) {
		return -1;
	}
	return 0;
}

int jpc_getuint16(jas_stream_t *in, uint_fast16_t *val)
{
	uint_fast16_t v;
	int c;
	if ((c = jas_stream_getc(in)) == EOF) {
		return -1;
	}
	v = c;
	if ((c = jas_stream_getc(in)) == EOF) {
		return -1;
	}
	v = (v << 8) | c;
	if (val) {
		*val = v;
	}
	return 0;
}

int jpc_putuint16(jas_stream_t *out, uint_fast16_t val)
{
	if (jas_stream_putc(out, (val >> 8) & 0xff) == EOF ||
	  jas_stream_putc(out, val & 0xff) == EOF) {
		return -1;
	}
	return 0;
}

int jpc_getuint32(jas_stream_t *in, uint_fast32_t *val)
{
	uint_fast32_t v;
	int c;
	if ((c = jas_stream_getc(in)) == EOF) {
		return -1;
	}
	v = c;
	if ((c = jas_stream_getc(in)) == EOF) {
		return -1;
	}
	v = (v << 8) | c;
	if ((c = jas_stream_getc(in)) == EOF) {
		return -1;
	}
	v = (v << 8) | c;
	if ((c = jas_stream_getc(in)) == EOF) {
		return -1;
	}
	v = (v << 8) | c;
	if (val) {
		*val = v;
	}
	return 0;
}

int jpc_putuint32(jas_stream_t *out, uint_fast32_t val)
{
	if (jas_stream_putc(out, (val >> 24) & 0xff) == EOF ||
	  jas_stream_putc(out, (val >> 16) & 0xff) == EOF ||
	  jas_stream_putc(out, (val >> 8) & 0xff) == EOF ||
	  jas_stream_putc(out, val & 0xff) == EOF) {
		return -1;
	}
	return 0;
}

/******************************************************************************\
* Miscellany
\******************************************************************************/

static jpc_mstabent_t *jpc_mstab_lookup(int id)
{
	jpc_mstabent_t *mstabent;
	for (mstabent = jpc_mstab;; ++mstabent) {
		if (mstabent->id == id || mstabent->id < 0) {
			return mstabent;
		}
	}
	assert(0);
	return 0;
}

int jpc_validate(jas_stream_t *in)
{
	int n;
	int i;
	unsigned char buf[2];

	assert(JAS_STREAM_MAXPUTBACK >= 2);

	if ((n = jas_stream_read(in, (char *) buf, 2)) < 0) {
		return -1;
	}
	for (i = n - 1; i >= 0; --i) {
		if (jas_stream_ungetc(in, buf[i]) == EOF) {
			return -1;
		}
	}
	if (n < 2) {
		return -1;
	}
	if (buf[0] == (JPC_MS_SOC >> 8) && buf[1] == (JPC_MS_SOC & 0xff)) {
		return 0;
	}
	return -1;
}

int jpc_getdata(jas_stream_t *in, jas_stream_t *out, long len)
{
	return jas_stream_copy(out, in, len);
}

int jpc_putdata(jas_stream_t *out, jas_stream_t *in, long len)
{
	return jas_stream_copy(out, in, len);
}