WIP: Support custom Rust targets

Support custom Rust targets defined in a JSON file.

Signed-off-by: Jonathan Schwender <[email protected]>

cmake/Corrosion.cmake

@@ -111,8 +111,13 @@ function(_corrosion_parse_platform manifest rust_version target_triple)
     # vendor is optional - We detect if vendor is present by matching against a known list of
     # vendors. The next field is the OS, which we assume to always be present, while the last field
     # is again optional and contains the environment.
+    # The target-triple may optionally also be a path to a json file, however we still require the
+    # filename (wihout the extenion) to follow the "arch-(vendor-)os(-env)" syntax.
+    # todo: alternatively we could just pass the target triple through as is if parsing fails,
+    # and just not add any libs or other os dependent options, since it is likely a custom OS
+    # anyway.
     string(REGEX MATCH
-            "^([^-]+)-((${known_vendors_joined})-)?([^-]+)(-([^-]+))?$"
+            "([a-z0-9_]+)-((${known_vendors_joined})-)?([a-z0-9_]+)(-([a-z0-9_]+))?(\.json)?$"
             whole_match
             "${target_triple}"
     )

test/config/ParseTargetTriple/CMakeLists.txt

@@ -0,0 +1,20 @@
+# This test is supposed to ensure that the regex in _corrosion_parse_platform works as expected.
+cmake_minimum_required(VERSION 3.15)
+
+project(ParseTargetTriple LANGUAGES C)
+
+add_subdirectory(../../.. corrosion)
+
+
+# Important built-in target triples.
+_corrosion_parse_platform("Cargo.toml" "1.55" "x86_64-unknown-linux-gnu")
+_corrosion_parse_platform("Cargo.toml" "1.55" "aarch64-unknown-linux-gnu")
+_corrosion_parse_platform("Cargo.toml" "1.55" "aarch64-fuchsia")
+
+# Custom json file. The file doesn't need to exist for the test.
+_corrosion_parse_platform("Cargo.toml" "1.55" "../../blah/x86_64-unknown-custom-gnu.json")
+_corrosion_parse_platform("Cargo.toml" "1.55" "x86_64-unknown-custom-gnu.json")
+_corrosion_parse_platform("Cargo.toml" "1.55" "/path/to/x86_64-unknown-custom-gnu.json")
+_corrosion_parse_platform("Cargo.toml" "1.55" "../../blah/x86_64-custom_os.json")
+
+

test/config/ParseTargetTriple/Cargo.toml

@@ -0,0 +1 @@
+# Pseudo manifest, just used in CMake to set some source file properties.

test/config/ParseTargetTriple/Test.cmake

@@ -0,0 +1,10 @@
+execute_process(
+    COMMAND
+        ${CMAKE_COMMAND} ${CMAKE_CURRENT_LIST_DIR}
+    COMMAND_ECHO STDOUT
+    RESULT_VARIABLE SUCCESS
+)
+
+if (NOT SUCCESS EQUAL 0)
+    message(FATAL_ERROR)
+endif()