add Builder.dupePkg()

mimics the duplication of strings in `Builder` for `Pkg`. This
ensures the lifetime of the memory backing strings in a `Pkg`
struct and the `Pkg.dependencies` slice is not shorter than the
`Builder` that the data is associated with.
This commit is contained in:
Jesse Rudolph
2020-07-07 14:19:34 -05:00
committed by Andrew Kelley
parent b0684bf084
commit e821a57683

View File

@@ -311,6 +311,23 @@ pub const Builder = struct {
return the_copy;
}
pub fn dupePkg(self: *Builder, package: Pkg) Pkg {
var the_copy = Pkg{
.name = self.dupe(package.name),
.path = self.dupePath(package.path),
};
if (package.dependencies) |dependencies| {
const new_dependencies = self.allocator.alloc(Pkg, dependencies.len) catch unreachable;
the_copy.dependencies = new_dependencies;
for (dependencies) |dep_package, i| {
new_dependencies[i] = self.dupePkg(dep_package);
}
}
return the_copy;
}
pub fn addWriteFile(self: *Builder, file_path: []const u8, data: []const u8) *WriteFileStep {
const write_file_step = self.addWriteFiles();
write_file_step.add(file_path, data);
@@ -1826,7 +1843,7 @@ pub const LibExeObjStep = struct {
}
pub fn addPackage(self: *LibExeObjStep, package: Pkg) void {
self.packages.append(package) catch unreachable;
self.packages.append(self.dupePkg(package)) catch unreachable;
}
pub fn addPackagePath(self: *LibExeObjStep, name: []const u8, pkg_index_path: []const u8) void {
@@ -2691,6 +2708,47 @@ pub const InstalledFile = struct {
path: []const u8,
};
test "Builder.dupePkg()" {
var arena = std.heap.ArenaAllocator.init(std.testing.allocator);
defer arena.deinit();
var builder = try Builder.create(
&arena.allocator,
"test",
"test",
"test",
);
defer builder.destroy();
var pkg_dep = Pkg{
.name = "pkg_dep",
.path = "/not/a/pkg_dep.zig",
};
var pkg_top = Pkg{
.name = "pkg_top",
.path = "/not/a/pkg_top.zig",
.dependencies = &[_]Pkg{pkg_dep},
};
const dupe = builder.dupePkg(pkg_top);
const original_deps = pkg_top.dependencies.?;
const dupe_deps = dupe.dependencies.?;
// probably the same top level package details
std.testing.expectEqualStrings(pkg_top.name, dupe.name);
// probably the same dependencies
std.testing.expectEqual(original_deps.len, dupe_deps.len);
std.testing.expectEqual(original_deps[0].name, pkg_dep.name);
// could segfault otherwise if pointers in duplicated package's fields are
// the same as those in stack allocated package's fields
std.testing.expect(dupe_deps.ptr != original_deps.ptr);
std.testing.expect(dupe.name.ptr != pkg_top.name.ptr);
std.testing.expect(dupe.path.ptr != pkg_top.path.ptr);
std.testing.expect(dupe_deps[0].name.ptr != pkg_dep.name.ptr);
std.testing.expect(dupe_deps[0].path.ptr != pkg_dep.path.ptr);
}
test "" {
// The only purpose of this test is to get all these untested functions
// to be referenced to avoid regression so it is okay to skip some targets.