--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/platform/java/jni/fitzinputstream.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,178 @@
+// Copyright (C) 2004-2021 Artifex Software, Inc.
+//
+// This file is part of MuPDF.
+//
+// MuPDF is free software: you can redistribute it and/or modify it under the
+// terms of the GNU Affero General Public License as published by the Free
+// Software Foundation, either version 3 of the License, or (at your option)
+// any later version.
+//
+// MuPDF is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+// details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with MuPDF. If not, see <https://www.gnu.org/licenses/agpl-3.0.en.html>
+//
+// Alternative licensing terms are available from the licensor.
+// For commercial licensing, see <https://www.artifex.com/> or contact
+// Artifex Software, Inc., 39 Mesa Street, Suite 108A, San Francisco,
+// CA 94129, USA, for further information.
+
+/* FitzInputStream interface */
+
+JNIEXPORT jboolean JNICALL
+FUN(FitzInputStream_markSupported)(JNIEnv *env, jobject self)
+{
+	fz_context *ctx = get_context(env);
+	fz_stream *stm = from_FitzInputStream_safe(env, self);
+	jboolean closed = JNI_TRUE;
+
+	if (!ctx || !stm) return JNI_FALSE;
+
+	closed = (*env)->GetBooleanField(env, self, fid_FitzInputStream_closed);
+	if (closed) jni_throw_uoe(env, "stream closed");
+
+	return stm->seek != NULL;
+}
+
+JNIEXPORT void JNICALL
+FUN(FitzInputStream_mark)(JNIEnv *env, jobject self, jint readlimit)
+{
+	fz_context *ctx = get_context(env);
+	fz_stream *stm = from_FitzInputStream_safe(env, self);
+	jlong markpos = 0;
+	jboolean closed = JNI_TRUE;
+
+	if (!ctx || !stm) return;
+	if (stm->seek == NULL) jni_throw_uoe_void(env, "mark not supported");
+
+	closed = (*env)->GetBooleanField(env, self, fid_FitzInputStream_closed);
+	if (closed) jni_throw_uoe_void(env, "stream closed");
+
+	fz_try(ctx)
+		markpos = fz_tell(ctx, stm);
+	fz_catch(ctx)
+		jni_rethrow_void(env, ctx);
+
+	(*env)->SetLongField(env, self, fid_FitzInputStream_markpos, markpos);
+}
+
+JNIEXPORT void JNICALL
+FUN(FitzInputStream_reset)(JNIEnv *env, jobject self)
+{
+	fz_context *ctx = get_context(env);
+	fz_stream *stm = from_FitzInputStream_safe(env, self);
+	jboolean closed = JNI_TRUE;
+	jlong markpos = -1;
+
+	if (!ctx || !stm) return;
+
+	if (stm->seek == NULL) jni_throw_uoe_void(env, "reset not supported");
+	closed = (*env)->GetBooleanField(env, self, fid_FitzInputStream_closed);
+	if (closed) jni_throw_uoe_void(env, "stream closed");
+
+	markpos = (*env)->GetLongField(env, self, fid_FitzInputStream_markpos);
+	if (markpos < 0) jni_throw_io_void(env, "mark not set");
+
+	fz_try(ctx)
+		fz_seek(ctx, stm, markpos, SEEK_SET);
+	fz_catch(ctx)
+		jni_rethrow_void(env, ctx);
+}
+
+JNIEXPORT jint JNICALL
+FUN(FitzInputStream_available)(JNIEnv *env, jobject self)
+{
+	fz_context *ctx = get_context(env);
+	fz_stream *stm = from_FitzInputStream_safe(env, self);
+	jint available = 0;
+	jboolean closed = JNI_TRUE;
+
+	if (!ctx || !stm) return -1;
+
+	closed = (*env)->GetBooleanField(env, self, fid_FitzInputStream_closed);
+	if (closed) jni_throw_uoe(env, "stream closed");
+
+	fz_try(ctx)
+		available = fz_available(ctx, stm, 1);
+	fz_catch(ctx)
+		jni_rethrow(env, ctx);
+
+	return available;
+}
+
+JNIEXPORT jint JNICALL
+FUN(FitzInputStream_readByte)(JNIEnv *env, jobject self)
+{
+	fz_context *ctx = get_context(env);
+	fz_stream *stm = from_FitzInputStream_safe(env, self);
+	jboolean closed = JNI_TRUE;
+	jbyte b = 0;
+
+	if (!ctx || !stm) return -1;
+
+	closed = (*env)->GetBooleanField(env, self, fid_FitzInputStream_closed);
+	if (closed) jni_throw_uoe(env, "stream closed");
+
+	fz_try(ctx)
+		b = fz_read_byte(ctx, stm);
+	fz_catch(ctx)
+		jni_rethrow(env, ctx);
+
+	return b;
+}
+
+JNIEXPORT jint JNICALL
+FUN(FitzInputStream_readArray)(JNIEnv *env, jobject self, jobject jarr, jint off, jint len)
+{
+	fz_context *ctx = get_context(env);
+	fz_stream *stm = from_FitzInputStream_safe(env, self);
+	jboolean closed = JNI_TRUE;
+	jbyte *arr = NULL;
+	jint n = 0;
+
+	if (!ctx || !stm) return -1;
+	if (!jarr) jni_throw_arg(env, "buffer must not be null");
+
+	closed = (*env)->GetBooleanField(env, self, fid_FitzInputStream_closed);
+	if (closed) jni_throw_uoe(env, "stream closed");
+
+	arr = (*env)->GetByteArrayElements(env, jarr, NULL);
+	if (!arr) jni_throw_arg(env, "cannot get buffer to read into");
+
+	fz_try(ctx)
+		n = fz_read(ctx, stm, (unsigned char *) arr + off, len);
+	fz_always(ctx)
+		(*env)->ReleaseByteArrayElements(env, jarr, arr, 0);
+	fz_catch(ctx)
+		jni_rethrow(env, ctx);
+
+	return n;
+}
+
+JNIEXPORT void JNICALL
+FUN(FitzInputStream_finalize)(JNIEnv *env, jobject self)
+{
+	fz_context *ctx = get_context(env);
+	fz_stream *stm = from_FitzInputStream_safe(env, self);
+	if (!ctx || !stm) return;
+	(*env)->SetLongField(env, self, fid_FitzInputStream_pointer, 0);
+	fz_drop_stream(ctx, stm);
+}
+
+JNIEXPORT void JNICALL
+FUN(FitzInputStream_close)(JNIEnv *env, jobject self)
+{
+	fz_context *ctx = get_context(env);
+	fz_stream *stm = from_FitzInputStream_safe(env, self);
+	jboolean closed = JNI_TRUE;
+
+	if (!ctx || !stm) return;
+
+	closed = (*env)->GetBooleanField(env, self, fid_FitzInputStream_closed);
+	if (closed) jni_throw_uoe_void(env, "stream closed");
+
+	(*env)->SetBooleanField(env, self, fid_FitzInputStream_closed, JNI_TRUE);
+}