Fuzz: Avoid using temporary files

- When built for fuzzing, expose special versions of tj3LoadImage*()
  that accept a FILE handle.

- Rename cjpeg_main() to cjpeg_fuzzer() and allow a FILE handle to be
  passed to it as well.

- Use fmemopen() to obtain a FILE handle from the fuzzer input data.

CMakeLists.txt

@@ -869,6 +869,7 @@ endif()
 ###############################################################################
 
 if(WITH_FUZZ)
+  add_definitions(-DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
   add_subdirectory(fuzz)
 endif()
 

fuzz/cjpeg.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (C)2021, 2024 D. R. Commander.  All Rights Reserved.
+ * Copyright (C)2021, 2024, 2026 D. R. Commander.  All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -29,13 +29,10 @@
 /* This fuzz target wraps cjpeg in order to test esoteric compression options
    as well as the GIF and Targa readers. */
 
-#define main  cjpeg_main
 #define CJPEG_FUZZER
 extern "C" {
 #include "../src/cjpeg.c"
 }
-#undef main
-#undef CJPEG_FUZZER
 
 #include <stdint.h>
 #include <unistd.h>
@@ -43,40 +40,36 @@ extern "C" {
 
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
-  char filename[FILENAME_MAX] = { 0 };
   char *argv1[] = {
     (char *)"cjpeg", (char *)"-dct", (char *)"float", (char *)"-memdst",
     (char *)"-optimize", (char *)"-quality", (char *)"100,99,98",
     (char *)"-restart", (char *)"2", (char *)"-sample", (char *)"4x1,2x2,1x2",
-    (char *)"-targa", NULL
+    (char *)"-targa"
   };
   char *argv2[] = {
     (char *)"cjpeg", (char *)"-arithmetic", (char *)"-dct", (char *)"float",
     (char *)"-memdst", (char *)"-quality", (char *)"90,80,70", (char *)"-rgb",
     (char *)"-sample", (char *)"2x2", (char *)"-smooth", (char *)"50",
-    (char *)"-targa", NULL
+    (char *)"-targa"
   };
-  int fd = -1;
+  FILE *file = NULL;
 
-  snprintf(filename, FILENAME_MAX, "/tmp/libjpeg-turbo_cjpeg_fuzz.XXXXXX");
+  if ((file = fmemopen((void *)data, size, "r")) == NULL)
-  if ((fd = mkstemp(filename)) < 0 || write(fd, data, size) < 0)
     goto bailout;
 
-  argv1[12] = argv2[13] = filename;
+  fseek(file, 0, SEEK_SET);
+  cjpeg_fuzzer(12, argv1, file);
+  fseek(file, 0, SEEK_SET);
+  cjpeg_fuzzer(13, argv2, file);
 
-  cjpeg_main(13, argv1);
+  argv1[11] = argv2[12] = NULL;
-  cjpeg_main(14, argv2);
 
-  argv1[12] = argv2[13] = NULL;
+  fseek(file, 0, SEEK_SET);
-  argv1[11] = argv2[12] = filename;
+  cjpeg_fuzzer(11, argv1, file);
-
+  fseek(file, 0, SEEK_SET);
-  cjpeg_main(12, argv1);
+  cjpeg_fuzzer(12, argv2, file);
-  cjpeg_main(13, argv2);
 
 bailout:
-  if (fd >= 0) {
+  if (file) fclose(file);
-    close(fd);
-    if (strlen(filename) > 0) unlink(filename);
-  }
   return 0;
 }

fuzz/compress.cc

@@ -33,6 +33,10 @@
 #include <string.h>
 #include <unistd.h>
 
+extern "C" unsigned char *
+_tj3LoadImageFromFileHandle8(tjhandle handle, FILE *file, int *width,
+                             int align, int *height, int *pixelFormat);
+
 
 #define NUMTESTS  7
 
@@ -48,8 +52,8 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
   tjhandle handle = NULL;
   unsigned char *srcBuf = NULL, *dstBuf = NULL;
-  int width = 0, height = 0, fd = -1, ti;
+  int width = 0, height = 0, ti;
-  char filename[FILENAME_MAX] = { 0 };
+  FILE *file = NULL;
   struct test tests[NUMTESTS] = {
     { TJPF_RGB, TJSAMP_444, 100 },
     { TJPF_BGR, TJSAMP_422, 90 },
@@ -60,8 +64,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     { TJPF_CMYK, TJSAMP_440, 40 }
   };
 
-  snprintf(filename, FILENAME_MAX, "/tmp/libjpeg-turbo_compress_fuzz.XXXXXX");
+  if ((file = fmemopen((void *)data, size, "r")) == NULL)
-  if ((fd = mkstemp(filename)) < 0 || write(fd, data, size) < 0)
     goto bailout;
 
   if ((handle = tj3Init(TJINIT_COMPRESS)) == NULL)
@@ -83,8 +86,9 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     tj3Set(handle, TJPARAM_MAXPIXELS, 1048576);
     /* tj3LoadImage8() will refuse to load images larger than 1 Megapixel, so
        we don't need to check the width and height here. */
-    if ((srcBuf = tj3LoadImage8(handle, filename, &width, 1, &height,
+    fseek(file, 0, SEEK_SET);
-                                &pf)) == NULL)
+    if ((srcBuf = _tj3LoadImageFromFileHandle8(handle, file, &width, 1,
+                                               &height, &pf)) == NULL)
       continue;
 
     dstSize = maxBufSize = tj3JPEGBufSize(width, height, tests[ti].subsamp);
@@ -118,10 +122,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 bailout:
   tj3Free(dstBuf);
   tj3Free(srcBuf);
-  if (fd >= 0) {
+  if (file) fclose(file);
-    close(fd);
-    if (strlen(filename) > 0) unlink(filename);
-  }
   tj3Destroy(handle);
   return 0;
 }

fuzz/compress12.cc

@@ -33,6 +33,10 @@
 #include <string.h>
 #include <unistd.h>
 
+extern "C" short *
+_tj3LoadImageFromFileHandle12(tjhandle handle, FILE *file, int *width,
+                              int align, int *height, int *pixelFormat);
+
 
 #define NUMTESTS  7
 
@@ -49,8 +53,8 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
   tjhandle handle = NULL;
   short *srcBuf = NULL;
   unsigned char *dstBuf = NULL;
-  int width = 0, height = 0, fd = -1, ti;
+  int width = 0, height = 0, ti;
-  char filename[FILENAME_MAX] = { 0 };
+  FILE *file = NULL;
   struct test tests[NUMTESTS] = {
     { TJPF_RGB, TJSAMP_444, 100 },
     { TJPF_BGR, TJSAMP_422, 90 },
@@ -61,8 +65,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     { TJPF_CMYK, TJSAMP_440, 40 }
   };
 
-  snprintf(filename, FILENAME_MAX, "/tmp/libjpeg-turbo_compress12_fuzz.XXXXXX");
+  if ((file = fmemopen((void *)data, size, "r")) == NULL)
-  if ((fd = mkstemp(filename)) < 0 || write(fd, data, size) < 0)
     goto bailout;
 
   if ((handle = tj3Init(TJINIT_COMPRESS)) == NULL)
@@ -83,8 +86,9 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     tj3Set(handle, TJPARAM_MAXPIXELS, 1048576);
     /* tj3LoadImage12() will refuse to load images larger than 1 Megapixel, so
        we don't need to check the width and height here. */
-    if ((srcBuf = tj3LoadImage12(handle, filename, &width, 1, &height,
+    fseek(file, 0, SEEK_SET);
-                                 &pf)) == NULL)
+    if ((srcBuf = _tj3LoadImageFromFileHandle12(handle, file, &width, 1,
+                                                &height, &pf)) == NULL)
       continue;
 
     dstSize = maxBufSize = tj3JPEGBufSize(width, height, tests[ti].subsamp);
@@ -118,10 +122,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 bailout:
   tj3Free(dstBuf);
   tj3Free(srcBuf);
-  if (fd >= 0) {
+  if (file) fclose(file);
-    close(fd);
-    if (strlen(filename) > 0) unlink(filename);
-  }
   tj3Destroy(handle);
   return 0;
 }

fuzz/compress12_lossless.cc

@@ -33,6 +33,10 @@
 #include <string.h>
 #include <unistd.h>
 
+extern "C" short *
+_tj3LoadImageFromFileHandle12(tjhandle handle, FILE *file, int *width,
+                              int align, int *height, int *pixelFormat);
+
 
 #define NUMTESTS  7
 
@@ -48,8 +52,8 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
   tjhandle handle = NULL;
   short *srcBuf = NULL;
   unsigned char *dstBuf = NULL;
-  int width = 0, height = 0, fd = -1, ti;
+  int width = 0, height = 0, ti;
-  char filename[FILENAME_MAX] = { 0 };
+  FILE *file = NULL;
   struct test tests[NUMTESTS] = {
     { TJPF_RGB, 12, 1, 0 },
     { TJPF_BGR, 11, 2, 2 },
@@ -60,8 +64,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     { TJPF_CMYK, 12, 7, 0 }
   };
 
-  snprintf(filename, FILENAME_MAX, "/tmp/libjpeg-turbo_compress_fuzz.XXXXXX");
+  if ((file = fmemopen((void *)data, size, "r")) == NULL)
-  if ((fd = mkstemp(filename)) < 0 || write(fd, data, size) < 0)
     goto bailout;
 
   if ((handle = tj3Init(TJINIT_COMPRESS)) == NULL)
@@ -80,8 +83,9 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     tj3Set(handle, TJPARAM_MAXPIXELS, 1048576);
     /* tj3LoadImage12() will refuse to load images larger than 1 Megapixel, so
        we don't need to check the width and height here. */
-    if ((srcBuf = tj3LoadImage12(handle, filename, &width, 1, &height,
+    fseek(file, 0, SEEK_SET);
-                                 &pf)) == NULL)
+    if ((srcBuf = _tj3LoadImageFromFileHandle12(handle, file, &width, 1,
+                                                &height, &pf)) == NULL)
       continue;
 
     dstSize = maxBufSize = tj3JPEGBufSize(width, height, TJSAMP_444);
@@ -116,10 +120,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 bailout:
   tj3Free(dstBuf);
   tj3Free(srcBuf);
-  if (fd >= 0) {
+  if (file) fclose(file);
-    close(fd);
-    if (strlen(filename) > 0) unlink(filename);
-  }
   tj3Destroy(handle);
   return 0;
 }

fuzz/compress16_lossless.cc

@@ -33,6 +33,10 @@
 #include <string.h>
 #include <unistd.h>
 
+extern "C" unsigned short *
+_tj3LoadImageFromFileHandle16(tjhandle handle, FILE *file, int *width,
+                              int align, int *height, int *pixelFormat);
+
 
 #define NUMTESTS  7
 
@@ -48,8 +52,8 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
   tjhandle handle = NULL;
   unsigned short *srcBuf = NULL;
   unsigned char *dstBuf = NULL;
-  int width = 0, height = 0, fd = -1, ti;
+  int width = 0, height = 0, ti;
-  char filename[FILENAME_MAX] = { 0 };
+  FILE *file = NULL;
   struct test tests[NUMTESTS] = {
     { TJPF_RGB, 16, 1, 0 },
     { TJPF_BGR, 15, 2, 2 },
@@ -60,8 +64,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     { TJPF_CMYK, 16, 7, 0 }
   };
 
-  snprintf(filename, FILENAME_MAX, "/tmp/libjpeg-turbo_compress_fuzz.XXXXXX");
+  if ((file = fmemopen((void *)data, size, "r")) == NULL)
-  if ((fd = mkstemp(filename)) < 0 || write(fd, data, size) < 0)
     goto bailout;
 
   if ((handle = tj3Init(TJINIT_COMPRESS)) == NULL)
@@ -80,8 +83,9 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     tj3Set(handle, TJPARAM_MAXPIXELS, 1048576);
     /* tj3LoadImage16() will refuse to load images larger than 1 Megapixel, so
        we don't need to check the width and height here. */
-    if ((srcBuf = tj3LoadImage16(handle, filename, &width, 1, &height,
+    fseek(file, 0, SEEK_SET);
-                                 &pf)) == NULL)
+    if ((srcBuf = _tj3LoadImageFromFileHandle16(handle, file, &width, 1,
+                                                &height, &pf)) == NULL)
       continue;
 
     dstSize = maxBufSize = tj3JPEGBufSize(width, height, TJSAMP_444);
@@ -116,10 +120,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 bailout:
   tj3Free(dstBuf);
   tj3Free(srcBuf);
-  if (fd >= 0) {
+  if (file) fclose(file);
-    close(fd);
-    if (strlen(filename) > 0) unlink(filename);
-  }
   tj3Destroy(handle);
   return 0;
 }

fuzz/compress_lossless.cc

@@ -33,6 +33,10 @@
 #include <string.h>
 #include <unistd.h>
 
+extern "C" unsigned char *
+_tj3LoadImageFromFileHandle8(tjhandle handle, FILE *file, int *width,
+                             int align, int *height, int *pixelFormat);
+
 
 #define NUMTESTS  7
 
@@ -47,8 +51,8 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
   tjhandle handle = NULL;
   unsigned char *srcBuf = NULL, *dstBuf = NULL;
-  int width = 0, height = 0, fd = -1, ti;
+  int width = 0, height = 0, ti;
-  char filename[FILENAME_MAX] = { 0 };
+  FILE *file = NULL;
   struct test tests[NUMTESTS] = {
     { TJPF_RGB, 8, 1, 0 },
     { TJPF_BGR, 7, 2, 5 },
@@ -59,8 +63,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     { TJPF_CMYK, 2, 7, 0 }
   };
 
-  snprintf(filename, FILENAME_MAX, "/tmp/libjpeg-turbo_compress_fuzz.XXXXXX");
+  if ((file = fmemopen((void *)data, size, "r")) == NULL)
-  if ((fd = mkstemp(filename)) < 0 || write(fd, data, size) < 0)
     goto bailout;
 
   if ((handle = tj3Init(TJINIT_COMPRESS)) == NULL)
@@ -79,8 +82,9 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     tj3Set(handle, TJPARAM_MAXPIXELS, 1048576);
     /* tj3LoadImage8() will refuse to load images larger than 1 Megapixel, so
        we don't need to check the width and height here. */
-    if ((srcBuf = tj3LoadImage8(handle, filename, &width, 1, &height,
+    fseek(file, 0, SEEK_SET);
-                                &pf)) == NULL)
+    if ((srcBuf = _tj3LoadImageFromFileHandle8(handle, file, &width, 1,
+                                               &height, &pf)) == NULL)
       continue;
 
     dstSize = maxBufSize = tj3JPEGBufSize(width, height, TJSAMP_444);
@@ -115,10 +119,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 bailout:
   tj3Free(dstBuf);
   tj3Free(srcBuf);
-  if (fd >= 0) {
+  if (file) fclose(file);
-    close(fd);
-    if (strlen(filename) > 0) unlink(filename);
-  }
   tj3Destroy(handle);
   return 0;
 }

fuzz/compress_yuv.cc

@@ -33,6 +33,10 @@
 #include <string.h>
 #include <unistd.h>
 
+extern "C" unsigned char *
+_tj3LoadImageFromFileHandle8(tjhandle handle, FILE *file, int *width,
+                             int align, int *height, int *pixelFormat);
+
 
 #define NUMTESTS  6
 
@@ -48,8 +52,8 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
   tjhandle handle = NULL;
   unsigned char *srcBuf = NULL, *dstBuf = NULL, *yuvBuf = NULL;
-  int width = 0, height = 0, fd = -1, ti;
+  int width = 0, height = 0, ti;
-  char filename[FILENAME_MAX] = { 0 };
+  FILE *file = NULL;
   struct test tests[NUMTESTS] = {
     { TJPF_XBGR, TJSAMP_444, 100 },
     { TJPF_XRGB, TJSAMP_422, 90 },
@@ -59,8 +63,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     { TJPF_GRAY, TJSAMP_GRAY, 50 }
   };
 
-  snprintf(filename, FILENAME_MAX, "/tmp/libjpeg-turbo_compress_yuv_fuzz.XXXXXX");
+  if ((file = fmemopen((void *)data, size, "r")) == NULL)
-  if ((fd = mkstemp(filename)) < 0 || write(fd, data, size) < 0)
     goto bailout;
 
   if ((handle = tj3Init(TJINIT_COMPRESS)) == NULL)
@@ -82,8 +85,9 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     tj3Set(handle, TJPARAM_MAXPIXELS, 1048576);
     /* tj3LoadImage8() will refuse to load images larger than 1 Megapixel, so
        we don't need to check the width and height here. */
-    if ((srcBuf = tj3LoadImage8(handle, filename, &width, 1, &height,
+    fseek(file, 0, SEEK_SET);
-                                &pf)) == NULL)
+    if ((srcBuf = _tj3LoadImageFromFileHandle8(handle, file, &width, 1,
+                                               &height, &pf)) == NULL)
       continue;
 
     dstSize = maxBufSize = tj3JPEGBufSize(width, height, tests[ti].subsamp);
@@ -123,10 +127,7 @@ bailout:
   tj3Free(dstBuf);
   free(yuvBuf);
   tj3Free(srcBuf);
-  if (fd >= 0) {
+  if (file) fclose(file);
-    close(fd);
-    if (strlen(filename) > 0) unlink(filename);
-  }
   tj3Destroy(handle);
   return 0;
 }

src/cjpeg.c

@@ -7,7 +7,7 @@
  * Lossless JPEG Modifications:
  * Copyright (C) 1999, Ken Murchison.
  * libjpeg-turbo Modifications:
- * Copyright (C) 2010, 2013-2014, 2017, 2019-2022, 2024-2025,
+ * Copyright (C) 2010, 2013-2014, 2017, 2019-2022, 2024-2026,
  *           D. R. Commander.
  * For conditions of distribution and use, see the accompanying README.ijg
  * file.
@@ -162,7 +162,7 @@ struct my_error_mgr {
   jmp_buf setjmp_buffer;
 };
 
-void my_error_exit(j_common_ptr cinfo)
+static void my_error_exit(j_common_ptr cinfo)
 {
   struct my_error_mgr *myerr = (struct my_error_mgr *)cinfo->err;
 
@@ -182,8 +182,6 @@ static void my_emit_message_fuzzer(j_common_ptr cinfo, int msg_level)
     jpeg_abort_compress(&cinfo); \
   } \
   jpeg_destroy_compress(&cinfo); \
-  if (input_file != stdin && input_file != NULL) \
-    fclose(input_file); \
   if (memdst) \
     free(outbuffer); \
   free(icc_profile); \
@@ -616,8 +614,13 @@ my_emit_message(j_common_ptr cinfo, int msg_level)
  * The main program.
  */
 
+#ifdef CJPEG_FUZZER
+static int
+cjpeg_fuzzer(int argc, char **argv, FILE *input_file)
+#else
 int
 main(int argc, char **argv)
+#endif
 {
   struct jpeg_compress_struct cinfo;
 #ifdef CJPEG_FUZZER
@@ -629,7 +632,9 @@ main(int argc, char **argv)
   struct cdjpeg_progress_mgr progress;
   int file_index;
   cjpeg_source_ptr src_mgr;
+#ifndef CJPEG_FUZZER
   FILE *input_file = NULL;
+#endif
   FILE *icc_file;
   JOCTET *icc_profile = NULL;
   long icc_len = 0;
@@ -696,6 +701,7 @@ main(int argc, char **argv)
   }
 #endif /* TWO_FILE_COMMANDLINE */
 
+#ifndef CJPEG_FUZZER
   /* Open the input file. */
   if (file_index < argc) {
     if ((input_file = fopen(argv[file_index], READ_BINARY)) == NULL) {
@@ -706,6 +712,7 @@ main(int argc, char **argv)
     /* default input file is stdin */
     input_file = read_stdin();
   }
+#endif
 
   /* Open the output file. */
   if (outfilename != NULL) {
@@ -818,8 +825,10 @@ main(int argc, char **argv)
   jpeg_destroy_compress(&cinfo);
 
   /* Close files, if we opened them */
+#ifndef CJPEG_FUZZER
   if (input_file != stdin)
     fclose(input_file);
+#endif
   if (output_file != stdout && output_file != NULL)
     fclose(output_file);
 

src/turbojpeg-mp.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (C)2009-2025 D. R. Commander.  All Rights Reserved.
+ * Copyright (C)2009-2026 D. R. Commander.  All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -290,8 +290,11 @@ bailout:
 /*************************** Packed-Pixel Image I/O **************************/
 
 /* TurboJPEG 3.0+ */
-DLLEXPORT _JSAMPLE *GET_NAME(tj3LoadImage, BITS_IN_JSAMPLE)
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
-  (tjhandle handle, const char *filename, int *width, int align, int *height,
+static
+#endif
+_JSAMPLE *GET_NAME(_tj3LoadImageFromFileHandle, BITS_IN_JSAMPLE)
+  (tjhandle handle, FILE *file, int *width, int align, int *height,
    int *pixelFormat)
 {
   static const char FUNCTION_NAME[] =
@@ -306,12 +309,11 @@ DLLEXPORT _JSAMPLE *GET_NAME(tj3LoadImage, BITS_IN_JSAMPLE)
   j_compress_ptr cinfo = NULL;
   cjpeg_source_ptr src;
   _JSAMPLE *dstBuf = NULL;
-  FILE *file = NULL;
   boolean invert;
 
   GET_TJINSTANCE(handle, NULL)
 
-  if (!filename || !width || align < 1 || !height || !pixelFormat ||
+  if (!file || !width || align < 1 || !height || !pixelFormat ||
       *pixelFormat < TJPF_UNKNOWN || *pixelFormat >= TJ_NUMPF)
     THROW("Invalid argument");
   if ((align & (align - 1)) != 0)
@@ -324,13 +326,6 @@ DLLEXPORT _JSAMPLE *GET_NAME(tj3LoadImage, BITS_IN_JSAMPLE)
   this2 = (tjinstance *)handle2;
   cinfo = &this2->cinfo;
 
-#ifdef _MSC_VER
-  if (fopen_s(&file, filename, "rb") || file == NULL)
-#else
-  if ((file = fopen(filename, "rb")) == NULL)
-#endif
-    THROW_UNIX("Cannot open input file");
-
   if ((tempc = getc(file)) < 0 || ungetc(tempc, file) == EOF)
     THROW_UNIX("Could not read input file")
   else if (tempc == EOF)
@@ -415,6 +410,56 @@ DLLEXPORT _JSAMPLE *GET_NAME(tj3LoadImage, BITS_IN_JSAMPLE)
 
 bailout:
   tj3Destroy(handle2);
+  if (retval < 0) { free(dstBuf);  dstBuf = NULL; }
+  return dstBuf;
+
+#else /* BITS_IN_JSAMPLE != 16 || defined(C_LOSSLESS_SUPPORTED) */
+
+  static const char ERROR_MSG[] =
+    "16-bit data precision requires lossless JPEG,\n"
+    "which was disabled at build time.";
+  _JSAMPLE *retval = NULL;
+
+  GET_TJINSTANCE(handle, NULL)
+  SNPRINTF(this->errStr, JMSG_LENGTH_MAX, "%s(): %s", FUNCTION_NAME,
+           ERROR_MSG);
+  this->isInstanceError = TRUE;  THROWG(ERROR_MSG, NULL)
+
+bailout:
+  return retval;
+
+#endif
+}
+
+DLLEXPORT _JSAMPLE *GET_NAME(tj3LoadImage, BITS_IN_JSAMPLE)
+  (tjhandle handle, const char *filename, int *width, int align, int *height,
+   int *pixelFormat)
+{
+  static const char FUNCTION_NAME[] =
+    GET_STRING(tj3LoadImage, BITS_IN_JSAMPLE);
+
+#if BITS_IN_JSAMPLE != 16 || defined(C_LOSSLESS_SUPPORTED)
+
+  int retval = 0;
+  _JSAMPLE *dstBuf = NULL;
+  FILE *file = NULL;
+
+  GET_TJINSTANCE(handle, NULL)
+
+  if (!filename)
+    THROW("Invalid argument");
+
+#ifdef _MSC_VER
+  if (fopen_s(&file, filename, "rb") || file == NULL)
+#else
+  if ((file = fopen(filename, "rb")) == NULL)
+#endif
+    THROW_UNIX("Cannot open input file");
+
+  dstBuf = GET_NAME(_tj3LoadImageFromFileHandle, BITS_IN_JSAMPLE)
+             (handle, file, width, align, height, pixelFormat);
+
+bailout:
   if (file) fclose(file);
   if (retval < 0) { free(dstBuf);  dstBuf = NULL; }
   return dstBuf;