Merge pull request #4890 from nulano/mingw-setup

.github/workflows/test-windows.yml

@@ -244,6 +244,7 @@ jobs:
               ${{ matrix.package }}-libimagequant \
               ${{ matrix.package }}-libjpeg-turbo \
               ${{ matrix.package }}-libraqm \
+              ${{ matrix.package }}-libtiff \
               ${{ matrix.package }}-libwebp \
               ${{ matrix.package }}-openjpeg2 \
               subversion
@@ -253,9 +254,7 @@ jobs:
           pushd depends && ./install_extra_test_images.sh && popd
 
       - name: Build Pillow
-        run: |
-          # libtiff is unable to open files
-          CFLAGS="-coverage" python3 setup.py build_ext --disable-tiff install
+        run: CFLAGS="-coverage" python3 setup.py build_ext install
 
       - name: Test Pillow
         run: |

docs/installation.rst

@@ -64,6 +64,8 @@ for raqm, libimagequant, and libxcb::
     python3 -m pip install --upgrade pip
     python3 -m pip install --upgrade Pillow
 
+To install Pillow in MSYS2, see `Building on Windows using MSYS2/MinGW`_.
+
 
 macOS Installation
 ^^^^^^^^^^^^^^^^^^
@@ -299,6 +301,42 @@ If you wish to compile Pillow manually, you can use the build scripts
 in the ``winbuild`` directory used for CI testing and development.
 These scripts require Visual Studio 2017 or newer and NASM.
 
+Building on Windows using MSYS2/MinGW
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+To build Pillow using MSYS2, make sure you run the **MSYS2 MinGW 32-bit** or
+**MSYS2 MinGW 64-bit** console, *not* **MSYS2** directly.
+
+The following instructions target the 64-bit build, for 32-bit
+replace all occurrences of ``mingw-w64-x86_64-`` with ``mingw-w64-i686-``.
+
+Make sure you have Python and GCC installed::
+
+    pacman -S \
+        mingw-w64-x86_64-gcc \
+        mingw-w64-x86_64-python3 \
+        mingw-w64-x86_64-python3-pip \
+        mingw-w64-x86_64-python3-setuptools
+
+Prerequisites are installed on **MSYS2 MinGW 64-bit** with::
+
+    pacman -S \
+        mingw-w64-x86_64-libjpeg-turbo \
+        mingw-w64-x86_64-zlib \
+        mingw-w64-x86_64-libtiff \
+        mingw-w64-x86_64-freetype \
+        mingw-w64-x86_64-lcms2 \
+        mingw-w64-x86_64-libwebp \
+        mingw-w64-x86_64-openjpeg2 \
+        mingw-w64-x86_64-libimagequant \
+        mingw-w64-x86_64-libraqm
+
+Now install Pillow with::
+
+    python3 -m pip install --upgrade pip
+    python3 -m pip install --upgrade Pillow
+
+
 Building on FreeBSD
 ^^^^^^^^^^^^^^^^^^^
 

setup.py

@@ -133,18 +133,6 @@ class RequiredDependencyException(Exception):
 PLATFORM_MINGW = os.name == "nt" and "GCC" in sys.version
 PLATFORM_PYPY = hasattr(sys, "pypy_version_info")
 
-if sys.platform == "win32" and PLATFORM_MINGW:
-    from distutils import cygwinccompiler
-
-    cygwin_versions = cygwinccompiler.get_versions()
-    if cygwin_versions[1] is None:
-        # ld version is None
-        # distutils cygwinccompiler might fetch the ld path from gcc
-        # Try the normal path instead
-        cygwin_versions = list(cygwin_versions)
-        cygwin_versions[1] = cygwinccompiler._find_exe_version("ld -v")
-        cygwinccompiler.get_versions = lambda: tuple(cygwin_versions)
-
 
 def _dbg(s, tp=None):
     if DEBUG:
@@ -528,11 +516,6 @@ class pil_build_ext(build_ext):
             _add_directory(library_dirs, "/lib")
 
         if sys.platform == "win32":
-            if PLATFORM_MINGW:
-                _add_directory(
-                    include_dirs, "C:\\msys64\\mingw32\\include\\libimagequant"
-                )
-
             # on Windows, look for the OpenJPEG libraries in the location that
             # the official installer puts them
             program_files = os.environ.get("ProgramFiles", "")
@@ -727,6 +710,10 @@ class pil_build_ext(build_ext):
         if feature.tiff:
             libs.append(feature.tiff)
             defs.append(("HAVE_LIBTIFF", None))
+            # FIXME the following define should be detected automatically
+            #       based on system libtiff, see #4237
+            if PLATFORM_MINGW:
+                defs.append(("USE_WIN32_FILEIO", None))
         if feature.xcb:
             libs.append(feature.xcb)
             defs.append(("HAVE_XCB", None))

src/libImaging/TiffDecode.c

@@ -20,6 +20,17 @@
 
 #include "TiffDecode.h"
 
+/* Convert C file descriptor to WinApi HFILE if LibTiff was compiled with tif_win32.c
+ *
+ * This cast is safe, as the top 32-bits of HFILE are guaranteed to be zero,
+ * see https://docs.microsoft.com/en-us/windows/win32/winprog64/interprocess-communication
+ */
+#ifndef USE_WIN32_FILEIO
+#define fd_to_tiff_fd(fd) (fd)
+#else
+#define fd_to_tiff_fd(fd) ((int)_get_osfhandle(fd))
+#endif
+
 void dump_state(const TIFFSTATE *state){
     TRACE(("State: Location %u size %d eof %d data: %p ifd: %d\n", (uint)state->loc,
            (int)state->size, (uint)state->eof, state->data, state->ifd));
@@ -316,7 +327,7 @@ int ImagingLibTiffDecode(Imaging im, ImagingCodecState state, UINT8* buffer, Py_
     if (clientstate->fp) {
         TRACE(("Opening using fd: %d\n",clientstate->fp));
         lseek(clientstate->fp,0,SEEK_SET); // Sometimes, I get it set to the end.
-        tiff = TIFFFdOpen(clientstate->fp, filename, mode);
+        tiff = TIFFFdOpen(fd_to_tiff_fd(clientstate->fp), filename, mode);
     } else {
         TRACE(("Opening from string\n"));
         tiff = TIFFClientOpen(filename, mode,
@@ -521,7 +532,7 @@ int ImagingLibTiffEncodeInit(ImagingCodecState state, char *filename, int fp) {
 
     if (fp) {
         TRACE(("Opening using fd: %d for writing \n",clientstate->fp));
-        clientstate->tiff = TIFFFdOpen(clientstate->fp, filename, mode);
+        clientstate->tiff = TIFFFdOpen(fd_to_tiff_fd(clientstate->fp), filename, mode);
     } else {
         // malloc a buffer to write the tif, we're going to need to realloc or something if we need bigger.
         TRACE(("Opening a buffer for writing \n"));