Add README.md and some Vezel repository scaffolding.

.editorconfig

@@ -0,0 +1,25 @@
+root = true
+
+[*]
+charset = utf-8
+indent_size = 4
+indent_style = space
+insert_final_newline = true
+max_line_length = 120
+tab_width = 4
+trim_trailing_whitespace = true
+
+[*.json]
+indent_size = 2
+
+[*.jsonc]
+indent_size = 2
+
+[*.vsconfig]
+indent_size = 2
+
+[*.yaml]
+indent_size = 2
+
+[*.yml]
+indent_size = 2

.gitattributes

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+* text
+*.verified.* text eol=lf
+*.ico binary
+*.pdf binary
+*.png binary
+*.zig eol=lf
+*.zon eol=lf

.github/CODEOWNERS

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+* @vezel-dev/graf-maintainers

.github/CONTRIBUTING.md

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+# Contributing
+
+This repository is a fork that only makes build system changes and provides Zig
+bindings. As such, most issues and pull requests should be directed
+[upstream](https://github.com/libffi/libffi). That said, if your issue or pull
+request is related to our fork's changes, then please see
+[our organization contribution guide](https://github.com/vezel-dev/.github/blob/master/CONTRIBUTING.md).
+
+Please note that, if you send a pull request and it is merged, it is quite
+likely that the record of your contribution will be lost, even though the change
+itself is kept. This happens because we rebase the `master` branch periodically
+and try to keep the number of commits on top of upstream to a minimum.

.github/SECURITY.md

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+# Security
+
+This repository is a fork that only makes build system changes and provides Zig
+bindings. As such, most security issues should be directed
+[upstream](https://github.com/libffi/libffi). That said, if you wish to report a
+security issue that is related to our fork's changes, then please see
+[our organization security policy](https://github.com/vezel-dev/.github/security/policy).

.github/dependabot.yml

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+# yaml-language-server: $schema=https://json.schemastore.org/dependabot-2.0.json
+version: 2
+updates:
+  - package-ecosystem: dotnet-sdk
+    directories:
+      - /
+    schedule:
+      interval: daily
+      timezone: Europe/Copenhagen
+      time: "12:00"
+    open-pull-requests-limit: 25
+    labels: []
+  - package-ecosystem: nuget
+    directories:
+      - /
+    schedule:
+      interval: daily
+      timezone: Europe/Copenhagen
+      time: "12:00"
+    open-pull-requests-limit: 25
+    labels: []

.markdownlint.json

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+{
+  "$schema": "https://raw.githubusercontent.com/DavidAnson/markdownlint/main/schema/markdownlint-config-schema.json",
+  "default": true,
+  "MD001": true,
+  "MD003": {
+    "style": "atx"
+  },
+  "MD004": {
+    "style": "asterisk"
+  },
+  "MD005": true,
+  "MD007": {
+    "start_indented": false,
+    "start_indent": 4,
+    "indent": 4
+  },
+  "MD009": {
+    "br_spaces": 0,
+    "strict": true
+  },
+  "MD010": {
+    "spaces_per_tab": 4
+  },
+  "MD011": true,
+  "MD012": true,
+  "MD013": {
+    "code_blocks": false,
+    "headings": false,
+    "tables": false
+  },
+  "MD014": true,
+  "MD018": true,
+  "MD019": true,
+  "MD020": true,
+  "MD021": true,
+  "MD022": true,
+  "MD023": true,
+  "MD024": true,
+  "MD025": true,
+  "MD026": {
+    "punctuation": "!,.:;?"
+  },
+  "MD027": true,
+  "MD028": true,
+  "MD029": {
+    "style": "ordered"
+  },
+  "MD030": true,
+  "MD031": true,
+  "MD032": true,
+  "MD033": {
+    "allowed_elements": [
+      "div",
+      "img",
+      "p",
+      "strong"
+    ]
+  },
+  "MD034": true,
+  "MD035": {
+    "style": "--------------------------------------------------------------------------------"
+  },
+  "MD036": {
+    "punctuation": "!,.:;?"
+  },
+  "MD037": true,
+  "MD038": true,
+  "MD039": true,
+  "MD040": {
+    "language_only": true
+  },
+  "MD041": true,
+  "MD042": true,
+  "MD043": false,
+  "MD044": true,
+  "MD045": true,
+  "MD046": {
+    "style": "fenced"
+  },
+  "MD047": true,
+  "MD048": {
+    "style": "backtick"
+  },
+  "MD049": {
+    "style": "asterisk"
+  },
+  "MD050": {
+    "style": "asterisk"
+  },
+  "MD051": true,
+  "MD052": true,
+  "MD053": {
+    "ignored_definitions": []
+  },
+  "MD054": {
+    "url_inline": false
+  },
+  "MD055": {
+    "style": "leading_and_trailing"
+  },
+  "MD056": true,
+  "MD058": true
+}

.netconfig

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+[file ".editorconfig"]
+	url = https://github.com/vezel-dev/.github/blob/master/syn/.editorconfig
+	sha = 25cfbb6a508a9fcf8444ef283ddfe7b2e5121bca
+	etag = df90691e6bc4d301e82e508fca55eed234028a335c3615cf916db00cb4a053f1
+	weak
+[file ".gitattributes"]
+	url = https://github.com/vezel-dev/.github/blob/master/syn/.gitattributes
+	sha = 0ff05334db6d820dd16428e1aad477ed83ca10ef
+	etag = 0a6a1f6373760bc1c03e09e1efeeb77109705f11b159afd759e11550b45ee950
+	weak
+[file ".markdownlint.json"]
+	url = https://github.com/vezel-dev/.github/blob/master/syn/.markdownlint.json
+	sha = 72ec690564533b1ad756f452be9b3ea5075ad124
+	etag = 6d74ad50782defb281b210a627cae9d255cbb419cdc705b0571f1653dbe02300
+	weak

.vscode/extensions.json

@@ -0,0 +1,14 @@
+{
+  "recommendations": [
+    "chdsbd.github-code-owners",
+    "codezombiech.gitignore",
+    "davidanson.vscode-markdownlint",
+    "editorconfig.editorconfig",
+    "github.vscode-github-actions",
+    "github.vscode-pull-request-github",
+    "llvm-vs-code-extensions.vscode-clangd",
+    "redhat.vscode-yaml",
+    "yy0931.gitconfig-lsp",
+    "ziglang.vscode-zig"
+  ]
+}

.vscode/settings.json

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+{
+  "files.exclude": {
+    ".zig-cache": true,
+    "zig-out": true
+  }
+}

README.md

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+# Vezel libffi Fork
+
+This is a friendly fork of [libffi](https://sourceware.org/libffi). The notable
+changes made in this fork are the additions of a [Zig](https://ziglang.org)
+build script, making it easy to integrate libffi into Zig projects using the Zig
+package manager, and a set of idiomatic Zig bindings for libffi's main API.
+Additionally, to reduce the package download size, we have removed a large
+number of files that are unnecessary when using libffi in a Zig project.
+Importantly, **all library source code is identical to upstream**, so in terms
+of API/ABI compatibility, using this fork is no different from linking to a
+system libffi package.
+
+## Usage
+
+The minimum Zig version supported by this project can be found in the
+`minimum_zig_version` field of the [`build.zig.zon`](build.zig.zon) file. We
+generally try to track the latest release of Zig. But do note that the `master`
+branch may sometimes contain code that only works with a `master` build of Zig.
+
+Please note that the `master` branch is rebased on top of upstream periodically.
+**You should use a release tag rather than `master`.** For example:
+
+```bash
+zig fetch --save=ffi https://github.com/vezel-dev/libffi/archive/vX.Y.Z-B.tar.gz
+# Or, to use Git:
+zig fetch --save=ffi git+https://github.com/vezel-dev/libffi.git#vX.Y.Z-B
+```
+
+(You can find the latest version on the
+[releases page](https://github.com/vezel-dev/libffi/releases).)
+
+Consume the library in your `build.zig`:
+
+```zig
+const ffi = b.dependency("ffi", .{
+    .target = target,
+    .optimize = optimize,
+});
+
+exe.root_module.addImport("ffi", ffi.module("ffi"));
+
+if (b.systemIntegrationOption("ffi", .{})) {
+    exe.linkSystemLibrary("ffi");
+} else {
+    exe.linkLibrary(ffi.artifact("ffi"));
+}
+```
+
+You can now use the Zig bindings in your code:
+
+```zig
+const builtin = @import("builtin");
+const std = @import("std");
+const stdio = @cImport(@cInclude("stdio.h"));
+const ffi = @import("ffi");
+
+pub fn main() !void {
+    std.debug.print("Calling C puts() on {s}.\n", .{builtin.cpu.arch.genericName()});
+
+    var func: ffi.Function = undefined;
+    var params = [_]*ffi.Type{
+        ffi.types.pointer,
+    };
+
+    try func.prepare(ffi.Abi.default, params.len, params[0..params.len], ffi.types.sint32);
+
+    var result: ffi.uarg = undefined;
+    var args = [params.len]*anyopaque{
+        @ptrCast(@constCast(&"Hello World")),
+    };
+
+    func.call(&stdio.puts, args[0..args.len], &result);
+
+    if (result == stdio.EOF) return error.IOError;
+}
+```
+
+And finally:
+
+```console
+$ zig build run
+Calling C puts() on x86.
+Hello World
+```
+
+Cross-compilation works too:
+
+```console
+$ zig build run -fqemu -Dtarget=aarch64-linux
+Calling C puts() on aarch64.
+Hello World
+```
+
+## License
+
+This project is licensed under the terms found in [`LICENSE`](LICENSE); this
+file is unchanged from upstream.

RELEASE.md

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+# Release
+
+Every upstream release should have a corresponding release branch and tag here.
+The branch should be named `release/vX.Y.Z`; that is, unlike normal Vezel
+convention, even a patch release gets a unique branch. The tag should be named
+`vX.Y.Z-B`, where B represents our one-based fork version. B is incremented
+whenever we make fixes to the Zig build script or bindings within the same
+upstream release cycle, and is reset for any new X/Y/Z combination.
+
+This is the procedure for creating a new release from an upstream release:
+
+1. Run `git checkout -b release/vX.Y.Z vX.Y.Z` to create and switch to the new
+   release branch.
+2. Cherry-pick our fork's commit range from `master` and resolve any conflicts
+   in the process.
+3. Adjust the libffi version in [`build.zig`](build.zig) and
+   [`build.zig.zon`](build.zig.zon), and then commit the changes.
+4. Make sure `zig build` works. Try cross-compiling for any targets that had
+   changes in the upstream release.
+5. Push the release branch.
+6. Run `git tag vX.Y.Z-B -m vX.Y.Z-B -s` to create and sign a release tag, then
+   push it.
+7. Go to the [releases page](https://github.com/vezel-dev/libffi/releases) to
+   create a release from the new tag. The release notes should just be a link to
+   the upstream release, such as
+   [this one](https://github.com/libffi/libffi/releases/tag/v3.4.6).
+
+(Obviously, step 2 will be easier if `master` is not lagging behind upstream.)
+
+The procedure for creating a release that only includes fixes to the Zig build
+script or bindings is simpler: Just commit the fix to the release branch and
+then proceed from step 4. Remember to increment the B value!
+
+If something goes wrong, you can run `git tag -d vX.Y.Z-B` and
+`git push origin :vX.Y.Z-B` to delete the tag until you resolve the issue(s),
+and then repeat whichever steps are necessary.

dotnet-tools.json

@@ -0,0 +1,18 @@
+{
+  "version": 1,
+  "isRoot": true,
+  "tools": {
+    "dotnet-config": {
+      "version": "1.2.0",
+      "commands": [
+        "dotnet-config"
+      ]
+    },
+    "dotnet-file": {
+      "version": "1.7.1",
+      "commands": [
+        "dotnet-file"
+      ]
+    }
+  }
+}

global.json

@@ -0,0 +1,8 @@
+{
+  "$schema": "https://json.schemastore.org/global.json",
+  "sdk": {
+    "version": "9.0.100",
+    "rollForward": "disable",
+    "allowPrelease": false
+  }
+}