--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/zint/backend/filemem.h	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,103 @@
+/*  filemem.h - write to file/memory abstraction */
+/*
+    libzint - the open source barcode library
+    Copyright (C) 2023-2024 Robin Stuart <rstuart114@gmail.com>
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+    3. Neither the name of the project nor the names of its contributors
+       may be used to endorse or promote products derived from this software
+       without specific prior written permission.
+
+    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+    ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
+    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+    SUCH DAMAGE.
+ */
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef Z_FILEMEM_H
+#define Z_FILEMEM_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+#include <stdio.h>
+#include "common.h"
+
+/* Whether `vsnprintf()` available */
+#if (defined(_MSC_VER) && _MSC_VER < 1900) || defined(ZINT_IS_C89) /* Pre-MSVC 2015 (C++ 14.0) or C89 */
+#define FM_NO_VSNPRINTF
+#endif
+
+struct filemem {
+    FILE *fp;
+    unsigned char *mem;
+    size_t memsize;     /* Size of `mem` buffer (capacity) */
+    size_t mempos;      /* Current position */
+    size_t memend;      /* For use by `fm_seek()`, points to highest `mempos` reached */
+    int flags;          /* BARCODE_MEMORY_FILE or BARCODE_STDOUT */
+    int err;            /* `errno` values, reset only on `fm_open()` */
+#ifdef FM_NO_VSNPRINTF
+    FILE *fp_null;      /* Only used for BARCODE_MEMORY_FILE */
+#endif
+};
+
+/* `fopen()` if file, setup memory buffer if BARCODE_MEMORY_FILE, returning 1 on success, 0 on failure */
+INTERNAL int fm_open(struct filemem *restrict const fmp, struct zint_symbol *symbol, const char *mode);
+
+/* `fwrite()` to file or memory, returning 1 on success, 0 on failure */
+INTERNAL int fm_write(const void *restrict ptr, const size_t size, const size_t nitems,
+                    struct filemem *restrict const fmp);
+
+/* `fputc()` to file or memory, returning 1 on success, 0 on failure */
+INTERNAL int fm_putc(const int ch, struct filemem *restrict const fmp);
+
+/* `fputs()` to file or memory, returning 1 on success, 0 on failure */
+INTERNAL int fm_puts(const char *str, struct filemem *restrict const fmp);
+
+/* `fprintf()` to file or memory, returning 1 on success, 0 on failure */
+INTERNAL int fm_printf(struct filemem *restrict const fmp, const char *format, ...) ZINT_FORMAT_PRINTF(2, 3);
+
+/* Output float without trailing zeroes to `fmp` with decimal pts `dp` (precision), returning 1 on success, 0 on
+   failure */
+INTERNAL int fm_putsf(const char *prefix, const int dp, const float arg, struct filemem *restrict const fmp);
+
+/* `fclose()` if file, set `symbol->memfile` & `symbol->memfile_size` if memory, returning 1 on success, 0 on
+   failure */
+INTERNAL int fm_close(struct filemem *restrict const fmp, struct zint_symbol *symbol);
+
+/* `fseek()` to file/memory offset, returning 1 on success, 0 on failure */
+INTERNAL int fm_seek(struct filemem *restrict const fmp, const long offset, const int whence);
+
+/* `ftell()` returns current file/memory offset if successful, -1 on failure */
+INTERNAL long fm_tell(struct filemem *restrict const fmp);
+
+/* Return `err`, which uses `errno` values; if file and `err` not set, test `ferror()` also */
+INTERNAL int fm_error(struct filemem *restrict const fmp);
+
+/* `fflush()` if file, no-op if memory, returning 1 on success, 0 on failure
+   NOTE: don't use, included only for libpng compatibility */
+INTERNAL int fm_flush(struct filemem *restrict const fmp);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+/* vim: set ts=4 sw=4 et : */
+#endif /* Z_FILEMEM_H */