chore: Build windows outputs into arch-specific build dirs.

This is just for local compilation so we don't need to keep deleting
`_build` and can instead build both in the same source directory.

Also removed some unused code for wine dll prefixes.

windows/cross-compile/build.sh

@@ -40,6 +40,8 @@ done
 
 # Common directory paths
 
+QTOX_BUILD_DIR="_build-$WINEARCH"
+readonly QTOX_BUILD_DIR
 QTOX_PREFIX_DIR="$(realpath install-prefix)"
 readonly QTOX_PREFIX_DIR
 QTOX_PACKAGE_DIR="$(realpath package-prefix)"
@@ -82,7 +84,7 @@ if [[ "$BUILD_TYPE" == "Release" ]]; then
     -DSTRICT_OPTIONS=ON \
     -DTEST_CROSSCOMPILING_EMULATOR=wine \
     -GNinja \
-    -B_build \
+    "-B$QTOX_BUILD_DIR" \
     "$QTOX_SRC_DIR"
 elif [[ "$BUILD_TYPE" == "Debug" ]]; then
   cmake -DCMAKE_TOOLCHAIN_FILE=/build/windows-toolchain.cmake \
@@ -95,18 +97,18 @@ elif [[ "$BUILD_TYPE" == "Debug" ]]; then
     -DTEST_CROSSCOMPILING_EMULATOR=wine \
     -GNinja \
     -DCMAKE_EXE_LINKER_FLAGS="-mconsole" \
-    -B_build \
+    "-B$QTOX_BUILD_DIR" \
     "$QTOX_SRC_DIR"
 fi
 
-cmake --build _build
+cmake --build "$QTOX_BUILD_DIR"
 
 mkdir -p "$QTOX_PREFIX_DIR"
-cp _build/qtox.exe "$QTOX_PREFIX_DIR"
+cp "$QTOX_BUILD_DIR/qtox.exe" "$QTOX_PREFIX_DIR"
 cp -r /export/* "$QTOX_PREFIX_DIR"
 
 export WINEQT_QPA_PLATFORM='offscreen'
-export WINEPREFIX="$PWD/_build/.wine"
+export WINEPREFIX="$PWD/$QTOX_BUILD_DIR/.wine"
 
 # Check if our main binary runs (just to see if any DLL errors happen early on).
 # This also initialises the wine directory for tests (avoiding race conditions).
@@ -119,7 +121,7 @@ if [[ $RUN_TESTS -ne 0 ]]; then
   # we want to see if the prefix dir has everything we need).
   export WINEQT_PLUGIN_PATH='z:\export'
   export WINEPATH='z:\export;z:\windows\bin'
-  ctest --test-dir _build --parallel "$(nproc)" --output-on-failure
+  ctest --test-dir "$QTOX_BUILD_DIR" --parallel "$(nproc)" --output-on-failure
 fi
 set -u
 
@@ -191,35 +193,41 @@ elif [[ "$ARCH" == "x86_64" ]]; then
   echo "$QTOX_PREFIX_DIR/libssl-3-x64.dll" >>runtime-dlls
 fi
 
+# Clean up any old file that may be here from previous runs.
+rm -f dlls-required
+
 # Create a tree of all required dlls
 # Assumes all .exe files are directly in $QTOX_PREFIX_DIR, not in subdirs
-while IFS= read -r line; do
-  if [[ "$ARCH" == "i686" ]]; then
-    WINE_DLL_DIR=("/usr/lib/x86_64-linux-gnu/wine/i386-windows")
-  elif [[ "$ARCH" == "x86_64" ]]; then
-    WINE_DLL_DIR=("/usr/lib/x86_64-linux-gnu/wine/x86_64-windows" "/usr/lib/x86_64-linux-gnu/wine/i386-windows")
-  fi
-  python3 /usr/local/bin/mingw-ldd.py "$line" --dll-lookup-dirs "$QTOX_PREFIX_DIR" "${WINE_DLL_DIR[@]}" --output-format tree >>dlls-required
-done < <(cat exes runtime-dlls)
+windows/cross-compile/check-dlls "-j$(nproc)" \
+  EXES="$(cat exes runtime-dlls)" \
+  ARCH="$ARCH" \
+  BUILD_DIR="$QTOX_BUILD_DIR" \
+  PREFIX_DIR="$QTOX_PREFIX_DIR"
 
-# Check that no extra dlls get bundled
-while IFS= read -r line; do
-  if ! grep -q "$line" dlls-required; then
-    echo "Error: extra dll included: $line. If this is a mistake and the dll is actually needed (e.g. it's loaded at runtime), please add it to the runtime dll list."
-    exit 1
-  fi
-done <dlls
+wc -l dlls-required
+
+# pipefail breaks the checks below (I don't understand why - if someone does,
+# please change this comment to explain).
+set +o pipefail
 
 # Check that no dll is missing. Ignore api-ms-win-*.dll, because they are
 # symbolic names pointing at kernel32.dll, user32.dll, etc.
 #
 # See https://github.com/nurupo/mingw-ldd/blob/master/README.md#api-set-dlls
-if grep -q 'not found' dlls-required | grep -q -v 'api-ms-win-'; then
+if grep -v 'api-ms-win-' dlls-required | grep -q 'not found'; then
   cat dlls-required
   echo "Error: Missing some dlls."
   exit 1
 fi
 
+# Check that no extra dlls get bundled
+while IFS= read -r line; do
+  if ! grep -q "$line" dlls-required; then
+    echo "Error: extra dll included: $line. If this is a mistake and the dll is actually needed (e.g. it's loaded at runtime), please add it to the runtime dll list."
+    exit 1
+  fi
+done <dlls
+
 # Check that OpenAL is bundled. It is availabe from WINE, but not on Windows systems
 if grep -q '/opt/wine-stable/lib/wine/i386-windows/openal32.dll' dlls-required; then
   cat dlls-required

windows/cross-compile/check-dlls

@@ -0,0 +1,16 @@
+#!/usr/bin/make -f
+
+ifeq ($(ARCH),i686)
+WINE_DLL_DIR=/usr/lib/i386-linux-gnu/wine/i386-windows
+endif
+ifeq ($(ARCH),x86_64)
+WINE_DLL_DIR=/usr/lib/x86_64-linux-gnu/wine/x86_64-windows /usr/lib/i386-linux-gnu/wine/i386-windows
+endif
+
+dlls-required: $(EXES:$(PREFIX_DIR)/%=$(BUILD_DIR)/%.check)
+	@cat $+ >$@
+
+$(BUILD_DIR)/%.check: $(PREFIX_DIR)/% $(WINE_DLL_DIR:=/kernel32.dll)
+	@echo "Checking $<"
+	@mkdir -p $(@D)
+	@python3 /usr/local/bin/mingw-ldd.py "$<" --dll-lookup-dirs "$(PREFIX_DIR)" $(WINE_DLL_DIR) --output-format tree >$@