[builds] Remove all legacy logic. (#21307)

We still need some of the source files from the legacy Mono library, but it's
only a few files, so just add them to the git repo.

Also implement caching of the .NET download, which speeds up clean rebuilds
significantly.

Note: all the files in the `builds/mono-ios-sdk-destdir` are a straight import
from the Mono archive, so those shouldn't need much reviewing (nor will I
change them unless absolutely necessary).

Make.config

@@ -637,22 +637,7 @@ JENKINS_RESULTS_DIRECTORY ?= $(abspath $(TOP)/jenkins-results)
 # Clone files instead of copying them on APFS file systems. Much faster.
 CP:=$(shell df -t apfs / >/dev/null 2>&1 && echo "cp -c" || echo "cp")
 
-# WORKAROUND, Ideally it should be xcode-$(XCODE_PRODUCT_BUILD_VERSION) but mono does not build binaries for each xcode release
-# Xcode 12.4 Build 12D4e
-XCODE_IOS_ARCHIVE_VERSION=xcode-12D4e
-# Xcode 12.4 Build 12D4e
-XCODE_MACOS_ARCHIVE_VERSION=xcode-12D4e
-MONO_IOS_FILENAME:=ios-release-Darwin-$(MONO_HASH).7z
-MONO_IOS_URL:=https://download.mono-project.com/mono-sdks/$(XCODE_IOS_ARCHIVE_VERSION)/$(MONO_IOS_FILENAME)
-
-# Setup various variables depending on whether mono is downloaded or built from source
-ifeq ($(MONO_BUILD_FROM_SOURCE),)
-MONO_IOS_SDK_DESTDIR:=$(abspath $(TOP)/builds/downloads/$(basename $(MONO_IOS_FILENAME)))
-MONO_BUILD_MODE=download-mono
-else
-MONO_IOS_SDK_DESTDIR:=$(abspath $(MONO_PATH)/sdks/out)
-MONO_BUILD_MODE=compile-mono
-endif
+MONO_IOS_SDK_DESTDIR:=$(abspath $(TOP)/builds/downloads/mono-ios-sdk-destdir)
 
 # This variable includes all the platforms we support, even those that might be disabled in this build.
 ALL_PLATFORMS=iOS tvOS watchOS macOS

builds/.gitignore

@@ -3,31 +3,3 @@ dotnet-install.sh
 BundledNETCorePlatformsPackageVersion.txt
 downloads
 .stamp*
-.deps.*.mk
-*.config.cache
-install
-mac32
-mac64
-llvm
-llvm64
-simulator86
-simulator64
-watchsimulator
-tvsimulator
-tools64
-cross
-cross64
-crosstv
-cross-watch
-target7
-target7s
-target64
-targettv
-targetwatch
-watchbcl
-mono-ios-sdk-destdir
-*.dylib
-*.o
-x86-64-slice*
-*.pkg
-

builds/Makefile

@@ -12,68 +12,22 @@ else
 DOTNET_ARCH=x64
 endif
 
-##
-## Mono download vs. build
-##
-
-download: download-mono
-download-mono: \
-	downloads/$(basename $(MONO_IOS_FILENAME)) \
-
-downloads/$(basename $(MONO_IOS_FILENAME)): MONO_URL=$(MONO_IOS_URL)
-
 include $(TOP)/mk/colors.mk
 
-DOWNLOADS = \
-	downloads/$(MONO_IOS_FILENAME) \
-
-# This target downloads the mono archives, there's one for Xamarin.iOS and one for Xamarin.Mac.
-# If doing many clean builds, it's possible to copy the downloaded zip file to ~/Library/Caches/xamarin-macios
-# to avoid having to download it every time. The zip files have to be copied manually, otherwise
-# we'd end up filling up a lot of hard drives around the world.
-$(DOWNLOADS):
-	$(Q) mkdir -p downloads
-	$(Q) echo "Downloading $(MONO_URL)..."
-	$(Q) if test -f ~/Library/Caches/xamarin-macios/$(notdir $@); then \
-		echo "Found a cached version of $(MONO_URL) in ~/Library/Caches/xamarin-macios/$(notdir $@)."; \
-		$(CP) ~/Library/Caches/xamarin-macios/$(notdir $@) $@.tmp; \
-	else \
-		EC=0; \
-		$(CURL_RETRY) $(MONO_URL) --output $@.tmp || EC=$$?; \
-		if [[ x$$EC == x22 ]]; then \
-			MSG="Could not download the archive %s because the URL doesn't exist. This can happen if bumping mono very soon after the corresponding commit was pushed to mono (i.e. the archive hasn't been built yet). If so, please wait a bit and try again."; \
-			printf "$(COLOR_RED)*** $$MSG$(COLOR_CLEAR)\n" "$(notdir $@)"; \
-			if test -n "$$FAILURE_REASON_PATH"; then printf "$$MSG\n" "[$(notdir $@)]($(MONO_URL))" >> "$$FAILURE_REASON_PATH"; fi; \
-		fi; \
-		if [[ x$$EC != x0 ]]; then exit $$EC; fi; \
-		if [[ "x$$MACIOS_CACHE_DOWNLOADS" != "x" ]]; then \
-			mkdir -p ~/Library/Caches/xamarin-macios/; \
-			$(CP) $@.tmp ~/Library/Caches/xamarin-macios/"$(notdir $@)"; \
-			echo "Cached the download of $(notdir $@) in ~/Library/Caches/xamarin-macios"; \
-		fi; \
-	fi
-	$(Q) mv $@.tmp $@
-	$(Q) echo "Downloaded $(MONO_URL)"
-
-downloads/%: downloads/%.7z
-	$(Q) echo "Unzipping $*..."
-	$(Q) rm -Rf $@.tmp
-	$(Q) 7z x $< -o$@.tmp
-	$(Q) find $@.tmp -exec touch {} +
-	$(Q) mv $@.tmp $@
-	$(Q) echo "Unzipped $*."
-
-downloads/%: downloads/%.nupkg
-	$(Q) echo "Unzipping $*..."
-	$(Q) rm -Rf $@.tmp
-	$(Q) unzip -d $@.tmp $<
-	$(Q) find $@.tmp -exec touch {} +
-	$(Q) mv $@.tmp $@
-	$(Q) echo "Unzipped $*."
+DOTNET_FILENAME=$(DOTNET_VERSION).tar.gz
+DOTNET_CACHE_FILENAME=$(HOME)/Library/Caches/xamarin-macios/$(DOTNET_FILENAME)
 
 downloads/$(DOTNET_INSTALL_NAME): dotnet-install.sh
 	$(Q) echo "Downloading and installing .NET $(DOTNET_VERSION) ($(DOTNET_ARCH)) into $@..."
-	$(Q) ./dotnet-install.sh --install-dir "$@.tmp" --version "$(DOTNET_VERSION)" --architecture $(DOTNET_ARCH) --no-path $$DOTNET_INSTALL_EXTRA_ARGS
+	$(Q) if test -f $(DOTNET_CACHE_FILENAME); then \
+			echo "Found a cached version of .NET $(DOTNET_VERSION) in $(DOTNET_CACHE_FILENAME)."; \
+			mkdir -p "$@.tmp"; \
+			tar -xzf $(DOTNET_CACHE_FILENAME) -C "$@.tmp"; \
+		else \
+			./dotnet-install.sh --install-dir "$@.tmp" --version "$(DOTNET_VERSION)" --architecture $(DOTNET_ARCH) --no-path --keep-zip --zip-path "downloads/$(DOTNET_FILENAME)" $$DOTNET_INSTALL_EXTRA_ARGS; \
+			cp -c downloads/$(DOTNET_FILENAME) $(DOTNET_CACHE_FILENAME); \
+			echo "Cached the download of $(DOTNET_FILENAME) in ~/Library/Caches/xamarin-macios"; \
+		fi
 	$(Q) rm -Rf "$@"
 	$(Q) mv "$@.tmp" "$@"
 	$(Q) echo "Downloaded and installed .NET $(DOTNET_VERSION) into $@."
@@ -108,10 +62,6 @@ dotnet-install.sh: Makefile
 	$(Q) chmod +x $@.tmp
 	$(Q) mv $@.tmp $@
 
-.stamp-download-mono: $(TOP)/Make.config $(TOP)/mk/mono.mk
-	$(MAKE) download-mono
-	$(Q) touch $@
-
 ifdef CUSTOM_DOTNET
 DOWNLOAD_DOTNET_VERSION=$(CUSTOM_DOTNET_VERSION)
 else
@@ -170,17 +120,7 @@ dotnet:: $(DOTNET_DOWNLOADS)
 all-local:: $(DOTNET_DOWNLOADS)
 
 clean-local::
-	$(Q) rm -Rf downloads .stamp-download-mono
-
-all-local:: .stamp-mono-ios-sdk-destdir
-
-.stamp-mono-ios-sdk-destdir: .stamp-$(MONO_BUILD_MODE)
-	ln -sf $(MONO_IOS_SDK_DESTDIR) mono-ios-sdk-destdir
-	$(Q) touch $@
-
-#
-# .NET
-#
+	$(Q) rm -Rf downloads
 
 DOTNET_COMMON_DIRECTORIES += \
 	$(foreach platform,$(DOTNET_PLATFORMS_UPPERCASE),$(DOTNET_DESTDIR)/$($(platform)_NUGET_SDK_NAME)) \
@@ -214,4 +154,3 @@ $(DOTNET_COMMON_DIRECTORIES):
 install-dotnet: $(DOTNET_COMMON_TARGETS)
 install-local:: install-dotnet
 all-local:: install-dotnet
-