From 048f6fac527cff53d32c2059f6b644a992a416a8 Mon Sep 17 00:00:00 2001
From: TellowKrinkle <tellowkrinkle@gmail.com>
Date: Mon, 1 Aug 2022 17:35:22 -0500
Subject: [PATCH 1/2] CMake: Properly include zstd include directories

---
 CMake/DolphinLibraryTools.cmake   | 10 ++++++++++
 CMakeLists.txt                    | 13 +++++--------
 Source/Core/DiscIO/CMakeLists.txt |  2 +-
 3 files changed, 16 insertions(+), 9 deletions(-)
 create mode 100644 CMake/DolphinLibraryTools.cmake

diff --git a/CMake/DolphinLibraryTools.cmake b/CMake/DolphinLibraryTools.cmake
new file mode 100644
index 0000000000..4f3a8df9f3
--- /dev/null
+++ b/CMake/DolphinLibraryTools.cmake
@@ -0,0 +1,10 @@
+# like add_library(new ALIAS old) but avoids add_library cannot create ALIAS target "new" because target "old" is imported but not globally visible. on older cmake
+# This can be replaced with a direct alias call once our minimum is cmake 3.18
+function(dolphin_alias_library new old)
+  string(REPLACE "::" "" library_no_namespace ${old})
+  if (NOT TARGET _alias_${library_no_namespace})
+    add_library(_alias_${library_no_namespace} INTERFACE)
+    target_link_libraries(_alias_${library_no_namespace} INTERFACE ${old})
+  endif()
+  add_library(${new} ALIAS _alias_${library_no_namespace})
+endfunction()
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 163ea2c943..5ca704eb48 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -127,6 +127,7 @@ include(CheckCCompilerFlag)
 include(CheckVendoringApproved)
 include(DolphinCompileDefinitions)
 include(DolphinDisableWarningsMSVC)
+include(DolphinLibraryTools)
 include(RemoveCompileFlag)
 
 # Enable folders for IDE
@@ -773,17 +774,13 @@ else()
   add_subdirectory(Externals/liblzma)
 endif()
 
-pkg_check_modules(ZSTD QUIET libzstd>=1.4.0)
-check_include_file(zstd.h HAVE_ZSTD_H)
-if(ZSTD_FOUND AND HAVE_ZSTD_H)
+pkg_check_modules(ZSTD QUIET libzstd>=1.4.0 IMPORTED_TARGET)
+if(ZSTD_FOUND)
   message(STATUS "Using shared zstd version: " ${ZSTD_VERSION})
+  dolphin_alias_library(zstd::zstd PkgConfig::ZSTD)
 else()
   check_vendoring_approved(zstd)
-  if(ZSTD_FOUND AND NOT HAVE_ZSTD_H)
-    message(STATUS "Shared zstd found but lacks headers, falling back to the static library")
-  else()
-    message(STATUS "Shared zstd not found, falling back to the static library")
-  endif()
+  message(STATUS "Shared zstd not found, falling back to the static library")
   add_subdirectory(Externals/zstd)
 endif()
 
diff --git a/Source/Core/DiscIO/CMakeLists.txt b/Source/Core/DiscIO/CMakeLists.txt
index 61790d89d8..eddfe9e2ff 100644
--- a/Source/Core/DiscIO/CMakeLists.txt
+++ b/Source/Core/DiscIO/CMakeLists.txt
@@ -71,7 +71,7 @@ PUBLIC
   core
   BZip2::BZip2
   lzma
-  zstd
+  zstd::zstd
 
 PRIVATE
   fmt::fmt

From 1bc133f3aed9254bf273a35a750bfc30f76e90f3 Mon Sep 17 00:00:00 2001
From: TellowKrinkle <tellowkrinkle@gmail.com>
Date: Mon, 1 Aug 2022 17:35:34 -0500
Subject: [PATCH 2/2] CMake: Properly include lzma include directories

---
 CMake/DolphinLibraryTools.cmake   | 10 ++++++++++
 CMakeLists.txt                    | 11 ++++-------
 Source/Core/DiscIO/CMakeLists.txt |  2 +-
 3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/CMake/DolphinLibraryTools.cmake b/CMake/DolphinLibraryTools.cmake
index 4f3a8df9f3..f1681306cb 100644
--- a/CMake/DolphinLibraryTools.cmake
+++ b/CMake/DolphinLibraryTools.cmake
@@ -8,3 +8,13 @@ function(dolphin_alias_library new old)
   endif()
   add_library(${new} ALIAS _alias_${library_no_namespace})
 endfunction()
+
+# Makes an imported target if it doesn't exist.  Useful for when find scripts from older versions of cmake don't make the targets you need
+function(dolphin_make_imported_target_if_missing target lib)
+  if(${lib}_FOUND AND NOT TARGET ${target})
+    add_library(_${lib} INTERFACE)
+    target_link_libraries(_${lib} INTERFACE "${${lib}_LIBRARIES}")
+    target_include_directories(_${lib} INTERFACE "${${lib}_INCLUDE_DIRS}")
+    add_library(${target} ALIAS _${lib})
+  endif()
+endfunction()
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5ca704eb48..fb72407bd6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -761,16 +761,13 @@ endif()
 
 # macOS ships with liblzma.dylib but no headers, so check for the headers too
 find_package(LibLZMA)
-check_include_file(lzma.h HAVE_LZMA_H)
-if(LIBLZMA_FOUND AND HAVE_LZMA_H)
+if(LIBLZMA_FOUND)
+  # Imported target added in CMake 3.14
+  dolphin_make_imported_target_if_missing(LibLZMA::LibLZMA LIBLZMA)
   message(STATUS "Using shared lzma")
 else()
   check_vendoring_approved(lzma)
-  if(LIBLZMA_FOUND AND NOT HAVE_LZMA_H)
-    message(STATUS "Shared lzma found but lacks headers, falling back to the static library")
-  else()
-    message(STATUS "Shared lzma not found, falling back to the static library")
-  endif()
+  message(STATUS "Shared lzma not found, falling back to the static library")
   add_subdirectory(Externals/liblzma)
 endif()
 
diff --git a/Source/Core/DiscIO/CMakeLists.txt b/Source/Core/DiscIO/CMakeLists.txt
index eddfe9e2ff..87bf6bea30 100644
--- a/Source/Core/DiscIO/CMakeLists.txt
+++ b/Source/Core/DiscIO/CMakeLists.txt
@@ -70,7 +70,7 @@ target_link_libraries(discio
 PUBLIC
   core
   BZip2::BZip2
-  lzma
+  LibLZMA::LibLZMA
   zstd::zstd
 
 PRIVATE