[cmake] refactor: cpmfile, deps prefetch, force system and more (#322)

CPM Dependencies are now managed in a singular json file, where each can be properly prefetched at-will via `tools/cpm-fetch.sh <packages...>`, or all at once via `tools/cpm-fetch-all.sh`.

Adds docs for CPMUtil as well.

Also adds `<package>_FORCE_{BUNDLED,SYSTEM}` overrides

Signed-off-by: crueter <crueter@eden-emu.dev>
Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/322
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>

1 files changed, 252 insertions, 0 deletions

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+# CPM
+
+CPM (CMake Package Manager) is the preferred method of managing dependencies within Eden.
+
+Global Options:
+
+- `YUZU_USE_CPM` is set by default on MSVC and Android. Other platforms should use this if certain "required" system dependencies (e.g. OpenSSL) are broken or missing
+  * If this is `OFF`, required system dependencies will be searched via `find_package`, although certain externals use CPM regardless.
+- `CPMUTIL_FORCE_SYSTEM` (default `OFF`): Require all CPM dependencies to use system packages. NOT RECOMMENDED!
+  * Many packages, e.g. mcl, sirit, xbyak, discord-rpc, are not generally available as a system package.
+  * You may optionally override these (see CPMUtil section)
+- `CPMUTIL_FORCE_BUNDLED` (default `ON` on MSVC and Android, `OFF` elsewhere): Require all CPM dependencies to use bundled packages.
+
+## CPMUtil
+
+CPMUtil is a wrapper around CPM that aims to reduce boilerplate and add useful utility functions to make dependency management a piece of cake.
+
+### AddPackage
+
+`AddPackage` is the core of the CPMUtil wrapper, and is generally the lowest level you will need to go when dealing with dependencies.
+
+**Identification/Fetching**
+
+- `NAME` (required): The package name (must be the same as the `find_package` name if applicable)
+- `VERSION`: The minimum version of this package that can be used on the system
+- `GIT_VERSION`: The version found within git, only used for identification
+- `URL`: The URL to fetch.
+- `REPO`: The GitHub repo to use (`owner/repo`).
+  * Only GitHub is supported for now, though other platforms will see support at some point
+- `TAG`: The tag to fetch, if applicable.
+- `ARTIFACT`: The name of the artifact, if applicable.
+- `SHA`: Commit sha to fetch, if applicable.
+- `BRANCH`: Branch to fetch, if applicable.
+
+The following configurations are supported, in descending order of precedence:
+
+- `URL`: Bare URL download, useful for custom artifacts
+  * If this is set, `GIT_URL` or `REPO` should be set to allow the dependency viewer to link to the project's Git repository.
+  * If this is NOT set, `REPO` must be defined.
+- `REPO + TAG + ARTIFACT`: GitHub release artifact
+  * The final download URL will be `https://github.com/${REPO}/releases/download/${TAG}/${ARTIFACT}`
+  * Useful for prebuilt libraries and prefetched archives
+- `REPO + TAG`: GitHub tag archive
+  * The final download URL will be `https://github.com/${REPO}/archive/refs/tags/${TAG}.tar.gz`
+  * Useful for pinning to a specific tag, better for build identification
+- `REPO + SHA`: GitHub commit archive
+  * The final download URL will be `https://github.com/${REPO}/archive/${SHA}.zip`
+  * Useful for pinning to a specific commit
+- `REPO + BRANCH`: GitHub branch archive
+  * The final download URL will be `https://github.com/${REPO}/archive/refs/heads/${BRANCH}.zip`
+  * Generally not recommended unless the branch is frozen
+- `REPO`: GitHub master archive
+  * The final download URL will be `https://github.com/${REPO}/archive/refs/heads/master.zip`
+  * Generally not recommended unless the project is dead
+
+**Hashing**
+
+Hashing is used for verifying downloads. It's highly recommended to use these.
+
+- `HASH_ALGO` (default `SHA512`): Hash algorithm to use
+
+Hashing strategies, descending order of precedence:
+
+- `HASH`: Bare hash verification, useful for static downloads e.g. commit archives
+- `HASH_SUFFIX`: Download the hash as `${DOWNLOAD_URL}.${HASH_SUFFIX}`
+  * The downloaded hash *must* match the hash algorithm and contain nothing but the hash; no filenames or extra content.
+- `HASH_URL`: Download the hash from a separate URL
+
+**Additional Options**
+
+- `KEY`: Custom cache key to use (stored as `.cache/cpm/${packagename_lower}/${key}`)
+  * Default is based on, in descending order of precedence:
+    - First 4 characters of the sha
+    - `GIT_VERSION`, or `VERSION` if not specified
+    - Tag
+    - Otherwise, CPM defaults will be used. This is not recommended as it doesn't produce reproducible caches
+- `DOWNLOAD_ONLY`: Whether or not to configure the downloaded package via CMake
+  * Useful to turn `OFF` if the project doesn't use CMake
+- `SOURCE_SUBDIR`: Subdirectory of the project containing a CMakeLists.txt file
+- `FIND_PACKAGE_ARGUMENTS`: Arguments to pass to the `find_package` call
+- `BUNDLED_PACKAGE`: Set to `ON` to force the usage of a bundled package
+- `OPTIONS`: Options to pass to the configuration of the package
+- `PATCHES`: Patches to apply to the package, stored in `.patch/${packagename_lower}/0001-patch-name.patch` and so on
+- Other arguments can be passed to CPM as well
+
+**Extra Variables**
+
+For each added package, users may additionally force usage of the system/bundled package.
+
+- `${package}_FORCE_SYSTEM`: Require the package to be installed on the system
+- `${package}_FORCE_BUNDLED`: Force the package to be fetched and use the bundled version
+
+**Bundled/System Switching**
+
+Descending order of precedence:
+- If `${package}_FORCE_SYSTEM` is true, requires the package to be on the system
+- If `${package}_FORCE_BUNDLED` is true, forcefully uses the bundled package
+- If `CPMUTIL_FORCE_SYSTEM` is true, requires the package to be on the system
+- If `CPMUTIL_FORCE_BUNDLED` is true, forcefully uses the bundled package
+- If the `BUNDLED_PACKAGE` argument is true, forcefully uses the bundled package
+- Otherwise, CPM will search for the package first, and if not found, will use the bundled package
+
+**Identification**
+
+All dependencies must be identifiable in some way for usage in the dependency viewer. Lists are provided in descending order of precedence.
+
+URLs:
+
+- `GIT_URL`
+- `REPO` as a GitHub repository
+- `URL`
+
+Versions (bundled):
+
+- `SHA`
+- `GIT_VERSION`
+- `VERSION`
+- `TAG`
+- "unknown"
+
+If the package is a system package, AddPackage will attempt to determine the package version and append ` (system)` to the identifier. Otherwise, it will be marked as `unknown (system)`
+
+### AddCIPackage
+
+Adds a package that follows crueter's CI repository spec.
+
+- `VERSION` (required): The version to get (the tag will be `v${VERSION}`)
+- `NAME` (required): Name used within the artifacts
+- `REPO` (required): CI repository, e.g. `crueter-ci/OpenSSL`
+- `PACKAGE` (required): `find_package` package name
+- `EXTENSION`: Artifact extension (default `tar.zst`)
+- `MIN_VERSION`: Minimum version for `find_package`. Only used if platform does not support this package as a bundled artifact
+- `DISABLED_PLATFORMS`: List of platforms that lack artifacts for this package. One of:
+  * `windows-amd64`
+  * `windows-arm64`
+  * `android`
+  * `solaris`
+  * `freebsd`
+  * `linux`
+  * `linux-aarch64`
+- `CMAKE_FILENAME`: Custom CMake filename, relative to the package root (default `${PACKAGE_ROOT}/${NAME}.cmake`)
+
+### AddJsonPackage
+
+This is the recommended method of usage for CPMUtil. In each directory that utilizes `CPMUtil`, there must be a `cpmfile.json` that defines dependencies in a similar manner to the individual calls.
+
+The cpmfile is an object of objects, with each sub-object being named according to the package's identifier, e.g. `openssl`, which can then be fetched with `AddJsonPackage(<identifier>)`. Options are designed to map closely to the argument names, and are always strings unless otherwise specified.
+
+- `package` -> `NAME` (`PACKAGE` for CI), defaults to the object key
+- `repo` -> `REPO`
+- `version` -> `VERSION`
+- `ci` (bool)
+
+If `ci` is `false`:
+
+- `hash` -> `HASH`
+- `sha` -> `SHA`
+- `tag` -> `TAG`
+- `artifact` -> `ARTIFACT`
+- `git_version` -> `GIT_VERSION`
+- `source_subdir` -> `SOURCE_SUBDIR`
+- `bundled` -> `BUNDLED_PACKAGE`
+- `find_args` -> `FIND_PACKAGE_ARGUMENTS`
+- `patches` -> `PATCHES` (array)
+- `options` -> `OPTIONS` (array)
+
+Other arguments aren't currently supported. If you wish to add them, see the `AddJsonPackage` function in `CMakeModules/CPMUtil.cmake`.
+
+If `ci` is `true`:
+
+- `name` -> `NAME`, defaults to the object key
+- `extension` -> `EXTENSION`, defaults to `tar.zst`
+- `min_version` -> `MIN_VERSION`
+- `cmake_filename` -> `CMAKE_FILENAME`
+- `extension` -> `EXTENSION`
+
+### Examples
+
+In order: OpenSSL CI, Boost (tag + artifact), discord-rpc (sha + options + patches), Opus (options + find_args)
+
+```json
+{
+    "openssl": {
+        "ci": true,
+        "package": "OpenSSL",
+        "name": "openssl",
+        "repo": "crueter-ci/OpenSSL",
+        "version": "3.5.2",
+        "min_version": "1.1.1"
+    },
+    "boost": {
+        "package": "Boost",
+        "repo": "boostorg/boost",
+        "tag": "boost-1.88.0",
+        "artifact": "boost-1.88.0-cmake.7z",
+        "hash": "e5b049e5b61964480ca816395f63f95621e66cb9bcf616a8b10e441e0e69f129e22443acb11e77bc1e8170f8e4171b9b7719891efc43699782bfcd4b3a365f01",
+        "git_version": "1.88.0",
+        "version": "1.57"
+    },
+    "opus": {
+        "package": "Opus",
+        "repo": "xiph/opus",
+        "sha": "5ded705cf4",
+        "hash": "0dc89e58ddda1f3bc6a7037963994770c5806c10e66f5cc55c59286fc76d0544fe4eca7626772b888fd719f434bc8a92f792bdb350c807968b2ac14cfc04b203",
+        "version": "1.3",
+        "find_args": "MODULE",
+        "options": [
+            "OPUS_BUILD_TESTING OFF",
+            "OPUS_BUILD_PROGRAMS OFF",
+            "OPUS_INSTALL_PKG_CONFIG_MODULE OFF",
+            "OPUS_INSTALL_CMAKE_CONFIG_MODULE OFF"
+        ]
+    },
+    "discord-rpc": {
+        "repo": "discord/discord-rpc",
+        "sha": "963aa9f3e5",
+        "hash": "386e1344e9a666d730f2d335ee3aef1fd05b1039febefd51aa751b705009cc764411397f3ca08dffd46205c72f75b235c870c737b2091a4ed0c3b061f5919bde",
+        "options": [
+            "BUILD_EXAMPLES OFF"
+        ],
+        "patches": [
+            "0001-cmake-version.patch",
+            "0002-no-clang-format.patch",
+            "0003-fix-cpp17.patch"
+        ]
+    },
+}
+```
+
+### Inclusion
+
+To include CPMUtil:
+
+```cmake
+set(CPMUTIL_JSON_FILE ${CMAKE_CURRENT_SOURCE_DIR}/cpmfile.json)
+include(CPMUtil)
+```
+
+You may omit the first line if you are not utilizing cpmfile.
+
+## Prefetching
+
+- To prefetch a CPM dependency (requires cpmfile):
+  * `tools/cpm-fetch.sh <packages>`
+- To prefetch all CPM dependencies:
+  * `tools/cpm-fetch-all.sh`
+
+Currently, `cpm-fetch.sh` defines the following directories for cpmfiles:
+
+`externals src/yuzu/externals externals/ffmpeg src/dynarmic/externals externals/nx_tzdb`
+
+Whenever you add a new cpmfile, update the script accordingly
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