1use std::path::{Path, PathBuf};
2use std::{fs, io};
3
4use rustc_data_structures::temp_dir::MaybeTempDir;
5use rustc_fs_util::TempDirBuilder;
6use rustc_middle::ty::TyCtxt;
7use rustc_session::Session;
8use rustc_session::config::{CrateType, OutFileName, OutputType};
9use rustc_session::output::filename_for_metadata;
10
11use crate::errors::{
12 BinaryOutputToTty, FailedCopyToStdout, FailedCreateEncodedMetadata, FailedCreateFile,
13 FailedCreateTempdir, FailedWriteError,
14};
15use crate::{EncodedMetadata, encode_metadata};
16
17pub const METADATA_FILENAME: &str = "lib.rmeta";
19
20pub fn emit_wrapper_file(sess: &Session, data: &[u8], tmpdir: &Path, name: &str) -> PathBuf {
26 let out_filename = tmpdir.join(name);
27 let result = fs::write(&out_filename, data);
28
29 if let Err(err) = result {
30 sess.dcx().emit_fatal(FailedWriteError { filename: out_filename, err });
31 }
32
33 out_filename
34}
35
36pub fn encode_and_write_metadata(tcx: TyCtxt<'_>) -> EncodedMetadata {
37 let out_filename = filename_for_metadata(tcx.sess, tcx.output_filenames(()));
38 let metadata_tmpdir = TempDirBuilder::new()
44 .prefix("rmeta")
45 .tempdir_in(out_filename.parent().unwrap_or_else(|| Path::new("")))
46 .unwrap_or_else(|err| tcx.dcx().emit_fatal(FailedCreateTempdir { err }));
47 let metadata_tmpdir = MaybeTempDir::new(metadata_tmpdir, tcx.sess.opts.cg.save_temps);
48 let metadata_filename = metadata_tmpdir.as_ref().join("full.rmeta");
49 let metadata_stub_filename = if !tcx.sess.opts.unstable_opts.embed_metadata
50 && !tcx.crate_types().contains(&CrateType::ProcMacro)
51 {
52 Some(metadata_tmpdir.as_ref().join("stub.rmeta"))
53 } else {
54 None
55 };
56
57 if tcx.needs_metadata() {
58 encode_metadata(tcx, &metadata_filename, metadata_stub_filename.as_deref());
59 } else {
60 std::fs::File::create(&metadata_filename).unwrap_or_else(|err| {
63 tcx.dcx().emit_fatal(FailedCreateFile { filename: &metadata_filename, err });
64 });
65 if let Some(metadata_stub_filename) = &metadata_stub_filename {
66 std::fs::File::create(metadata_stub_filename).unwrap_or_else(|err| {
67 tcx.dcx().emit_fatal(FailedCreateFile { filename: &metadata_stub_filename, err });
68 });
69 }
70 }
71
72 let _prof_timer = tcx.sess.prof.generic_activity("write_crate_metadata");
73
74 let need_metadata_file = tcx.sess.opts.output_types.contains_key(&OutputType::Metadata);
78 let (metadata_filename, metadata_tmpdir) = if need_metadata_file {
79 let filename = match out_filename {
80 OutFileName::Real(ref path) => {
81 if let Err(err) = non_durable_rename(&metadata_filename, path) {
82 tcx.dcx().emit_fatal(FailedWriteError { filename: path.to_path_buf(), err });
83 }
84 path.clone()
85 }
86 OutFileName::Stdout => {
87 if out_filename.is_tty() {
88 tcx.dcx().emit_err(BinaryOutputToTty);
89 } else if let Err(err) = copy_to_stdout(&metadata_filename) {
90 tcx.dcx()
91 .emit_err(FailedCopyToStdout { filename: metadata_filename.clone(), err });
92 }
93 metadata_filename
94 }
95 };
96 if tcx.sess.opts.json_artifact_notifications {
97 tcx.dcx().emit_artifact_notification(out_filename.as_path(), "metadata");
98 }
99 (filename, None)
100 } else {
101 (metadata_filename, Some(metadata_tmpdir))
102 };
103
104 let metadata =
106 EncodedMetadata::from_path(metadata_filename, metadata_stub_filename, metadata_tmpdir)
107 .unwrap_or_else(|err| {
108 tcx.dcx().emit_fatal(FailedCreateEncodedMetadata { err });
109 });
110
111 metadata
112}
113
114#[cfg(not(target_os = "linux"))]
115pub fn non_durable_rename(src: &Path, dst: &Path) -> std::io::Result<()> {
116 std::fs::rename(src, dst)
117}
118
119#[cfg(target_os = "linux")]
127pub fn non_durable_rename(src: &Path, dst: &Path) -> std::io::Result<()> {
128 let _ = std::fs::remove_file(dst);
129 std::fs::rename(src, dst)
130}
131
132pub fn copy_to_stdout(from: &Path) -> io::Result<()> {
133 let mut reader = fs::File::open_buffered(from)?;
134 let mut stdout = io::stdout();
135 io::copy(&mut reader, &mut stdout)?;
136 Ok(())
137}