src/librustdoc/html/sources.rs

   1 use crate::clean;
   2 use crate::docfs::PathError;
   3 use crate::fold::DocFolder;
   4 use crate::html::format::Buffer;
   5 use crate::html::highlight;
   6 use crate::html::layout;
   7 use crate::html::render::{Error, SharedContext, BASIC_KEYWORDS};
   8 use rustc_hir::def_id::LOCAL_CRATE;
   9 use rustc_span::source_map::FileName;
  10 use std::ffi::OsStr;
  11 use std::fs;
  12 use std::path::{Component, Path, PathBuf};
  13
  14 crate fn render(
  15     dst: &Path,
  16     scx: &mut SharedContext,
  17     krate: clean::Crate,
  18 ) -> Result<clean::Crate, Error> {
  19     info!("emitting source files");
  20     let dst = dst.join("src").join(&krate.name);
  21     scx.ensure_dir(&dst)?;
  22     let mut folder = SourceCollector { dst, scx };
  23     Ok(folder.fold_crate(krate))
  24 }
  25
  26 /// Helper struct to render all source code to HTML pages
  27 struct SourceCollector<'a> {
  28     scx: &'a mut SharedContext,
  29
  30     /// Root destination to place all HTML output into
  31     dst: PathBuf,
  32 }
  33
  34 impl<'a> DocFolder for SourceCollector<'a> {
  35     fn fold_item(&mut self, item: clean::Item) -> Option<clean::Item> {
  36         // If we're including source files, and we haven't seen this file yet,
  37         // then we need to render it out to the filesystem.
  38         if self.scx.include_sources
  39             // skip all synthetic "files"
  40             && item.source.filename.is_real()
  41             // skip non-local files
  42             && item.source.cnum == LOCAL_CRATE
  43         {
  44             // If it turns out that we couldn't read this file, then we probably
  45             // can't read any of the files (generating html output from json or
  46             // something like that), so just don't include sources for the
  47             // entire crate. The other option is maintaining this mapping on a
  48             // per-file basis, but that's probably not worth it...
  49             self.scx.include_sources = match self.emit_source(&item.source.filename) {
  50                 Ok(()) => true,
  51                 Err(e) => {
  52                     println!(
  53                         "warning: source code was requested to be rendered, \
  54                               but processing `{}` had an error: {}",
  55                         item.source.filename, e
  56                     );
  57                     println!("         skipping rendering of source code");
  58                     false
  59                 }
  60             };
  61         }
  62         self.fold_item_recur(item)
  63     }
  64 }
  65
  66 impl<'a> SourceCollector<'a> {
  67     /// Renders the given filename into its corresponding HTML source file.
  68     fn emit_source(&mut self, filename: &FileName) -> Result<(), Error> {
  69         let p = match *filename {
  70             FileName::Real(ref file) => file.local_path().to_path_buf(),
  71             _ => return Ok(()),
  72         };
  73         if self.scx.local_sources.contains_key(&*p) {
  74             // We've already emitted this source
  75             return Ok(());
  76         }
  77
  78         let contents = match fs::read_to_string(&p) {
  79             Ok(contents) => contents,
  80             Err(e) => {
  81                 return Err(Error::new(e, &p));
  82             }
  83         };
  84
  85         // Remove the utf-8 BOM if any
  86         let contents =
  87             if contents.starts_with("\u{feff}") { &contents[3..] } else { &contents[..] };
  88
  89         // Create the intermediate directories
  90         let mut cur = self.dst.clone();
  91         let mut root_path = String::from("../../");
  92         let mut href = String::new();
  93         clean_path(&self.scx.src_root, &p, false, |component| {
  94             cur.push(component);
  95             root_path.push_str("../");
  96             href.push_str(&component.to_string_lossy());
  97             href.push('/');
  98         });
  99         self.scx.ensure_dir(&cur)?;
 100         let mut fname = p.file_name().expect("source has no filename").to_os_string();
 101         fname.push(".html");
 102         cur.push(&fname);
 103         href.push_str(&fname.to_string_lossy());
 104
 105         let title = format!(
 106             "{} -- source",
 107             cur.file_name().expect("failed to get file name").to_string_lossy()
 108         );
 109         let desc = format!("Source to the Rust file `{}`.", filename);
 110         let page = layout::Page {
 111             title: &title,
 112             css_class: "source",
 113             root_path: &root_path,
 114             static_root_path: self.scx.static_root_path.as_deref(),
 115             description: &desc,
 116             keywords: BASIC_KEYWORDS,
 117             resource_suffix: &self.scx.resource_suffix,
 118             extra_scripts: &[&format!("source-files{}", self.scx.resource_suffix)],
 119             static_extra_scripts: &[&format!("source-script{}", self.scx.resource_suffix)],
 120         };
 121         let v = layout::render(
 122             &self.scx.layout,
 123             &page,
 124             "",
 125             |buf: &mut _| print_src(buf, &contents),
 126             &self.scx.themes,
 127         );
 128         self.scx.fs.write(&cur, v.as_bytes())?;
 129         self.scx.local_sources.insert(p.clone(), href);
 130         Ok(())
 131     }
 132 }
 133
 134 /// Takes a path to a source file and cleans the path to it. This canonicalizes
 135 /// things like ".." to components which preserve the "top down" hierarchy of a
 136 /// static HTML tree. Each component in the cleaned path will be passed as an
 137 /// argument to `f`. The very last component of the path (ie the file name) will
 138 /// be passed to `f` if `keep_filename` is true, and ignored otherwise.
 139 pub fn clean_path<F>(src_root: &Path, p: &Path, keep_filename: bool, mut f: F)
 140 where
 141     F: FnMut(&OsStr),
 142 {
 143     // make it relative, if possible
 144     let p = p.strip_prefix(src_root).unwrap_or(p);
 145
 146     let mut iter = p.components().peekable();
 147
 148     while let Some(c) = iter.next() {
 149         if !keep_filename && iter.peek().is_none() {
 150             break;
 151         }
 152
 153         match c {
 154             Component::ParentDir => f("up".as_ref()),
 155             Component::Normal(c) => f(c),
 156             _ => continue,
 157         }
 158     }
 159 }
 160
 161 /// Wrapper struct to render the source code of a file. This will do things like
 162 /// adding line numbers to the left-hand side.
 163 fn print_src(buf: &mut Buffer, s: &str) {
 164     let lines = s.lines().count();
 165     let mut cols = 0;
 166     let mut tmp = lines;
 167     while tmp > 0 {
 168         cols += 1;
 169         tmp /= 10;
 170     }
 171     write!(buf, "<pre class=\"line-numbers\">");
 172     for i in 1..=lines {
 173         write!(buf, "<span id=\"{0}\">{0:1$}</span>\n", i, cols);
 174     }
 175     write!(buf, "</pre>");
 176     write!(buf, "{}", highlight::render_with_highlighting(s, None, None, None));
 177 }