Add [vcpkg].overlay-ports feature

docs/cmake-toml.md

@@ -163,12 +163,15 @@ Variables emit a [`set`](https://cmake.org/cmake/help/latest/command/set.html) a
 version = "2024.03.25"
 url = "https://github.com/microsoft/vcpkg/archive/refs/tags/2024.03.25.tar.gz"
 packages = ["fmt", "zlib"]
+overlay-ports = ["my-ports"]
 ```
 
 The vcpkg `version` will automatically generate the `url` from the [official repository](https://github.com/microsoft/vcpkg/releases). For a custom registry you can specify your own `url` (and omit the `version`). You can browse available packages on [vcpkg.io](https://vcpkg.io/en/packages.html).
 
 To specify package features you can use the following syntax: `imgui[docking-experimental,freetype,sdl2-binding,opengl3-binding]`.
 
+The `overlay-ports` feature allows you to embed vcpkg ports inside your project, without having to fork the main vcpkg registry or creating a custom registry. You can find more information in the relevant [documentation](https://learn.microsoft.com/en-us/vcpkg/concepts/overlay-ports).
+
 ## Packages
 
 ```toml

include/project_parser.hpp

@@ -48,6 +48,7 @@ struct Vcpkg {
     };
 
     std::vector<Package> packages;
+    std::vector<std::string> overlay_ports;
 
     bool enabled() const {
         return !packages.empty();

src/cmake_generator.cpp

@@ -936,7 +936,7 @@ void generate_cmake(const char *path, const parser::Project *parent_project) {
         ofs << R"({
   "$cmkr": "This file is automatically generated from cmake.toml - DO NOT EDIT",
   "$cmkr-url": "https://github.com/build-cpp/cmkr",
-  "$schema": "https://raw.githubusercontent.com/microsoft/vcpkg/master/scripts/vcpkg.schema.json",
+  "$schema": "https://raw.githubusercontent.com/microsoft/vcpkg-tool/main/docs/vcpkg.schema.json",
   "dependencies": [
 )";
 
@@ -993,7 +993,29 @@ void generate_cmake(const char *path, const parser::Project *parent_project) {
         ofs << "  ],\n";
         ofs << "  \"description\": \"" << escape(project.project_description) << "\",\n";
         ofs << "  \"name\": \"" << escape(vcpkg_escape_identifier(project.project_name)) << "\",\n";
-        ofs << R"(  "version-string": "")" << '\n';
+        ofs << "  \"version-string\": \"none\"";
+        const auto &overlay_ports = project.vcpkg.overlay_ports;
+        if (!overlay_ports.empty()) {
+            ofs << ",\n";
+            // Reference: https://learn.microsoft.com/en-us/vcpkg/reference/vcpkg-json#vcpkg-configuration
+            ofs << "  \"vcpkg-configuration\": {\n";
+            ofs << "    \"overlay-ports\": [\n";
+            for (size_t i = 0; i < overlay_ports.size(); i++) {
+                const auto &directory = overlay_ports[i];
+                if (!fs::is_directory(directory)) {
+                    throw std::runtime_error("[vcpkg].overlay-ports is not a directory: " + directory);
+                }
+                ofs << "      \"" << escape(directory) << "\"";
+                if (i > 0) {
+                    ofs << ",";
+                }
+                ofs << "\n";
+            }
+            ofs << "    ]\n";
+            ofs << "  }\n";
+        } else {
+            ofs << "\n";
+        }
         ofs << "}\n";
     }
 

src/project_parser.cpp

@@ -854,6 +854,8 @@ Project::Project(const Project *parent, const std::string &path, bool build) : p
             }
             vcpkg.packages.emplace_back(std::move(package));
         }
+
+        v.optional("overlay-ports", vcpkg.overlay_ports);
     }
 
     checker.check(conditions, true);