solve problem of finding paths for anonymous modules

This commit is contained in:
Emil Lerch 2023-09-18 11:37:30 -07:00
parent e4195103a2
commit 1014f89d3d
Signed by: lobo
GPG Key ID: A7B62D657EF764F8

View File

@ -20,8 +20,10 @@ pub fn configureBuild(b: *std.Build, exe: *std.Build.Step.Compile) !void {
// type of interface is necessary
// Add module
const file_location = try findFileLocation(b);
exe.addAnonymousModule("universal_lambda_handler", .{
.source_file = .{ .path = "upstream/src/universal_lambda.zig" },
// Source file can be anywhere on disk, does not need to be a subdirectory
.source_file = .{ .path = b.pathJoin(&[_][]const u8{ file_location, "universal_lambda.zig" }) },
.dependencies = &[_]std.Build.ModuleDependency{.{
.name = "build_options",
.module = try createOptionsModule(b, exe),
@ -29,6 +31,41 @@ pub fn configureBuild(b: *std.Build, exe: *std.Build.Step.Compile) !void {
});
}
/// This function relies on internal implementation of the build runner
/// When a developer launches "zig build", a program is compiled, with the
/// main entrypoint existing in build_runner.zig (this can be overridden by
/// by command line).
///
/// The code we see in build.zig is compiled into that program. The program
/// is named 'build' and stuck in the zig cache, then it is run. There are
/// two phases to the build.
///
/// Build phase, where a graph is established of the steps that need to be run,
/// then the "make phase", where the steps are actually executed. Steps have
/// a make function that is called.
///
/// This function is reaching into the struct that is the build_runner.zig, and
/// finding the location of the dependency for ourselves to determine the
/// location of our own file. This is, of course, brittle, but there does not
/// seem to be a better way at the moment, and we need this to be able to import
/// modules appropriately.
///
/// For development of this process directly, we'll allow a build option to
/// override this process completely, because during development it's easier
/// for the example build.zig to simply import the file directly than it is
/// to pull from a download location and update hashes every time we change
fn findFileLocation(b: *std.Build) ![]const u8 {
const build_root = b.option([]const u8, "universal_lambda_build_root", "Build root for universal lambda (development of universal lambda only)");
if (build_root) |br| {
return b.pathJoin(&[_][]const u8{ br, "src" });
}
const build_runner = @import("root");
const deps = build_runner.dependencies;
const build_roots = deps.build_root;
if (!@hasField(build_roots, "universal_lambda_build"))
@panic("Dependency in build.zig.zon must be named 'universal_lambda_build'");
return b.pathJoin(&[_][]const u8{ @field(build_roots, "universal_lambda_build"), "src" });
}
/// Make our target platform visible to runtime through an import
/// called "build_options". This will also be available to the consuming
/// executable if needed