github-actions: add Windows CI for Cygwin testsuite

.gitattributes

@@ -18,3 +18,4 @@
 #     file gets renamed again ...
 
 ChangeLog       merge=merge-changelog
+*.sh eol=lf

.github/workflows/build.yaml

@@ -38,6 +38,22 @@ jobs:
           name: install
           path: _dest/
 
+      - name: Build test programs
+        shell: msys2 {0}
+        run: |
+          make -C x86_64-pc-cygwin/winsup/testsuite -j8 \
+            CFLAGS="-O2 -pipe -ggdb -std=gnu89 -w" check_programs
+
+      - name: Bundle up worktree
+        shell: msys2 {0}
+        run: $WINDIR/system32/tar.exe -czf wt.tgz --exclude _dest --exclude .git --exclude wt.tgz .
+
+      - name: Upload worktree archive
+        uses: actions/upload-artifact@v7
+        with:
+          name: wt.tgz
+          path: wt.tgz
+
   generate-msys2-tests-matrix:
     runs-on: ubuntu-latest
     outputs:
@@ -93,3 +109,50 @@ jobs:
       - name: Run tests
         uses: msys2/msys2-tests@main
 
+  cygwin-tests:
+    needs: [build]
+    runs-on: windows-latest
+    steps:
+      - name: setup-msys2
+        uses: msys2/setup-msys2@v2
+        with:
+          msystem: MSYS
+          update: true
+          install: msys2-devel base-devel diffutils make perl busybox cygutils
+
+      - name: Download worktree archive
+        uses: actions/download-artifact@v7
+        with:
+          name: wt.tgz
+
+      - name: Extract worktree
+        shell: msys2 {0}
+        run: $WINDIR/system32/tar.exe -xzf wt.tgz
+
+      - name: Run the test suite of Cygwin
+        shell: msys2 {0}
+        run: |
+          export PATH=/usr/bin:$WINDIR/system32
+          export MAKEFLAGS=-j8
+          export MSYS=winsymlinks:nativestrict
+          WINSUP=$PWD/x86_64-pc-cygwin/winsup
+          cp $WINSUP/cygserver/cygserver.exe $WINSUP/testsuite/testinst/usr/bin/
+          ( cd $WINSUP/testsuite/testinst/usr/bin && PATH=$PWD:$WINDIR/system32 "$WINDIR/System32/WindowsPowerShell/v1.0/powershell.exe" -command '& .\cygserver.exe' & )
+          # cygserver is launched asynchronously; wait for it to come up before
+          # running the SysV IPC tests (semtest/shmtest/msgtest) that depend on
+          # it, otherwise they race its startup and fail intermittently.
+          for i in $(seq 1 60); do
+            "$WINDIR/System32/tasklist.exe" //FI "IMAGENAME eq cygserver.exe" 2>/dev/null | grep -qi cygserver && break
+            sleep 1
+          done
+          sleep 5
+          cd $WINSUP && make check AM_COLOR_TESTS=always
+
+      - name: Upload testsuite logs
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: cygwin-testsuite-logs
+          path: |
+            x86_64-pc-cygwin/winsup/testsuite/**/*.log
+            x86_64-pc-cygwin/winsup/testsuite/**/*.trs

winsup/cygwin/Makefile.am

@@ -620,8 +620,8 @@ $(NEW_DLL_NAME): $(LDSCRIPT) libdll.a $(VERSION_OFILES) $(LIBSERVER)\
 	$(newlib_build)/libm.a \
 	$(newlib_build)/libc.a \
 	-lgcc -lkernel32 -lntdll -Wl,-Map,msys.map
-	@$(MKDIR_P) ${target_builddir}/winsup/testsuite/testinst/bin/
-	$(AM_V_at)$(INSTALL_PROGRAM) $(NEW_DLL_NAME) ${target_builddir}/winsup/testsuite/testinst/bin/$(DLL_NAME)
+	@$(MKDIR_P) ${target_builddir}/winsup/testsuite/testinst/usr/bin/
+	$(AM_V_at)$(INSTALL_PROGRAM) $(NEW_DLL_NAME) ${target_builddir}/winsup/testsuite/testinst/usr/bin/$(DLL_NAME)
 
 # msys-2.0 import library
 toolopts=--cpu=@target_cpu@ --ar=@AR@ --as=@AS@ --nm=@NM@ --objcopy=@OBJCOPY@

winsup/testsuite/Makefile.am

@@ -318,7 +318,7 @@ check_PROGRAMS = \
 # flags for linking against the just built implib
 # TODO: use -nostdinc and to-be-installed headers as well?
 LDFLAGS_FOR_TESTDLL = -nodefaultlibs
-LDADD_FOR_TESTDLL = $(builddir)/../cygwin/libcygwin.a -lgcc -lkernel32 -luser32
+LDADD_FOR_TESTDLL = $(builddir)/../cygwin/libmsys-2.0.a -lgcc -lkernel32 -luser32
 
 # flags for test executables
 AM_CPPFLAGS = -I$(srcdir)/libltp/include
@@ -334,16 +334,24 @@ TESTS = $(check_PROGRAMS) \
 
 # expected fail tests
 XFAIL_TESTS = \
+	winsup.api/ltp/access01 \
+	winsup.api/ltp/access05 \
+	winsup.api/ltp/chmod01 \
 	winsup.api/ltp/setgroups01 \
 	winsup.api/ltp/setuid02 \
+	winsup.api/ltp/stat02 \
+	winsup.api/ltp/symlink01 \
+	winsup.api/ltp/symlink03 \
+	winsup.api/ltp/symlink05 \
 	winsup.api/ltp/ulimit01 \
+	winsup.api/ltp/umask03 \
 	winsup.api/ltp/unlink08 \
 	winsup.api/samples/sample-fail
 
 # cygrun.sh test-runner script, and variables used by it:
 LOG_COMPILER = $(srcdir)/cygrun.sh
 
-export runtime_root=$(abs_builddir)/testinst/bin
+export runtime_root=$(abs_builddir)/testinst/usr/bin
 export cygrun=$(builddir)/mingw/cygrun
 
 # Set up things in the Cygwin 'installation' at testsuite/testinst/ to provide
@@ -365,9 +373,9 @@ export cygrun=$(builddir)/mingw/cygrun
 
 check-local:
 	$(MKDIR_P) ${builddir}/testinst/tmp
-	cd ${builddir}/testinst/bin && cp /usr/libexec/busybox/bin/busybox.exe sh.exe
-	cd ${builddir}/testinst/bin && cp /usr/libexec/busybox/bin/busybox.exe sleep.exe
-	cd ${builddir}/testinst/bin && cp /usr/libexec/busybox/bin/busybox.exe ls.exe
+	cd ${builddir}/testinst/usr/bin && cp /usr/bin/busybox.exe sh.exe
+	cd ${builddir}/testinst/usr/bin && cp /usr/bin/busybox.exe sleep.exe
+	cd ${builddir}/testinst/usr/bin && cp /usr/bin/busybox.exe ls.exe
 
 # target to build all the programs needed by check, without running check
 check_programs: $(check_PROGRAMS)

winsup/testsuite/cygrun.sh

@@ -11,7 +11,7 @@ export PATH="$runtime_root:${PATH}"
 if [ "$1" = "./mingw/cygload" ]
 then
     windows_runtime_root=$(cygpath -m $runtime_root)
-    $cygrun "$exe -v -cygwin $windows_runtime_root/cygwin1.dll"
+    MSYS_NO_PATHCONV=1 $cygrun "$exe -v -cygwin $windows_runtime_root/msys-2.0.dll"
 else
     cygdrop $cygrun $exe
 fi

winsup/testsuite/libltp/lib/search_path.c

@@ -139,7 +139,11 @@ printf("search_path: cmd = %s, access_mode = %d, fullpath = %d\n", cmd, access_m
 			PATH_MAX);
 		    return -1;
 		}
-		sprintf(res_path, "%s/%s", curpath, cmd);
+		/* Avoid a leading "//": on Cygwin/MSYS2 a path starting with
+		   "//" denotes a UNC network path.  When cwd is the root "/"
+		   (as in the MSYS2 testsuite install-root) "%s/%s" would yield
+		   "//cmd"; collapse curpath to "" so we emit "/cmd" instead. */
+		sprintf(res_path, "%s/%s", strcmp(curpath, "/") ? curpath : "", cmd);
 	    }
 	    else
 	        strcpy(res_path, cmd);
@@ -202,7 +206,8 @@ printf("search_path: tmppath = %s\n", tmppath);
 	    continue;
 	}
 
-	sprintf(res_path, "%s/%s", tmppath, cmd);
+	/* Same UNC-path guard as above for the PATH-scan branch. */
+	sprintf(res_path, "%s/%s", strcmp(tmppath, "/") ? tmppath : "", cmd);
 #if DEBUG
 printf("search_path: res_path = '%s'\n", res_path);
 #endif