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85aaf69f | 1 | // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT |
223e47cc LB |
2 | // file at the top-level directory of this distribution and at |
3 | // http://rust-lang.org/COPYRIGHT. | |
4 | // | |
5 | // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or | |
6 | // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license | |
7 | // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your | |
8 | // option. This file may not be copied, modified, or distributed | |
9 | // except according to those terms. | |
10 | ||
223e47cc | 11 | //! Finds crate binaries and loads their metadata |
1a4d82fc JJ |
12 | //! |
13 | //! Might I be the first to welcome you to a world of platform differences, | |
14 | //! version requirements, dependency graphs, conflicting desires, and fun! This | |
15 | //! is the major guts (along with metadata::creader) of the compiler for loading | |
16 | //! crates and resolving dependencies. Let's take a tour! | |
17 | //! | |
18 | //! # The problem | |
19 | //! | |
20 | //! Each invocation of the compiler is immediately concerned with one primary | |
21 | //! problem, to connect a set of crates to resolved crates on the filesystem. | |
22 | //! Concretely speaking, the compiler follows roughly these steps to get here: | |
23 | //! | |
24 | //! 1. Discover a set of `extern crate` statements. | |
25 | //! 2. Transform these directives into crate names. If the directive does not | |
26 | //! have an explicit name, then the identifier is the name. | |
27 | //! 3. For each of these crate names, find a corresponding crate on the | |
28 | //! filesystem. | |
29 | //! | |
30 | //! Sounds easy, right? Let's walk into some of the nuances. | |
31 | //! | |
32 | //! ## Transitive Dependencies | |
33 | //! | |
34 | //! Let's say we've got three crates: A, B, and C. A depends on B, and B depends | |
35 | //! on C. When we're compiling A, we primarily need to find and locate B, but we | |
36 | //! also end up needing to find and locate C as well. | |
37 | //! | |
38 | //! The reason for this is that any of B's types could be composed of C's types, | |
39 | //! any function in B could return a type from C, etc. To be able to guarantee | |
40 | //! that we can always typecheck/translate any function, we have to have | |
41 | //! complete knowledge of the whole ecosystem, not just our immediate | |
42 | //! dependencies. | |
43 | //! | |
44 | //! So now as part of the "find a corresponding crate on the filesystem" step | |
45 | //! above, this involves also finding all crates for *all upstream | |
46 | //! dependencies*. This includes all dependencies transitively. | |
47 | //! | |
48 | //! ## Rlibs and Dylibs | |
49 | //! | |
50 | //! The compiler has two forms of intermediate dependencies. These are dubbed | |
51 | //! rlibs and dylibs for the static and dynamic variants, respectively. An rlib | |
52 | //! is a rustc-defined file format (currently just an ar archive) while a dylib | |
53 | //! is a platform-defined dynamic library. Each library has a metadata somewhere | |
54 | //! inside of it. | |
55 | //! | |
476ff2be SL |
56 | //! A third kind of dependency is an rmeta file. These are metadata files and do |
57 | //! not contain any code, etc. To a first approximation, these are treated in the | |
58 | //! same way as rlibs. Where there is both an rlib and an rmeta file, the rlib | |
59 | //! gets priority (even if the rmeta file is newer). An rmeta file is only | |
60 | //! useful for checking a downstream crate, attempting to link one will cause an | |
61 | //! error. | |
62 | //! | |
1a4d82fc JJ |
63 | //! When translating a crate name to a crate on the filesystem, we all of a |
64 | //! sudden need to take into account both rlibs and dylibs! Linkage later on may | |
65 | //! use either one of these files, as each has their pros/cons. The job of crate | |
66 | //! loading is to discover what's possible by finding all candidates. | |
67 | //! | |
68 | //! Most parts of this loading systems keep the dylib/rlib as just separate | |
69 | //! variables. | |
70 | //! | |
71 | //! ## Where to look? | |
72 | //! | |
73 | //! We can't exactly scan your whole hard drive when looking for dependencies, | |
74 | //! so we need to places to look. Currently the compiler will implicitly add the | |
75 | //! target lib search path ($prefix/lib/rustlib/$target/lib) to any compilation, | |
76 | //! and otherwise all -L flags are added to the search paths. | |
77 | //! | |
78 | //! ## What criterion to select on? | |
79 | //! | |
80 | //! This a pretty tricky area of loading crates. Given a file, how do we know | |
81 | //! whether it's the right crate? Currently, the rules look along these lines: | |
82 | //! | |
83 | //! 1. Does the filename match an rlib/dylib pattern? That is to say, does the | |
84 | //! filename have the right prefix/suffix? | |
85 | //! 2. Does the filename have the right prefix for the crate name being queried? | |
83c7162d XL |
86 | //! This is filtering for files like `libfoo*.rlib` and such. If the crate |
87 | //! we're looking for was originally compiled with -C extra-filename, the | |
88 | //! extra filename will be included in this prefix to reduce reading | |
89 | //! metadata from crates that would otherwise share our prefix. | |
1a4d82fc JJ |
90 | //! 3. Is the file an actual rust library? This is done by loading the metadata |
91 | //! from the library and making sure it's actually there. | |
92 | //! 4. Does the name in the metadata agree with the name of the library? | |
93 | //! 5. Does the target in the metadata agree with the current target? | |
94 | //! 6. Does the SVH match? (more on this later) | |
95 | //! | |
96 | //! If the file answers `yes` to all these questions, then the file is | |
97 | //! considered as being *candidate* for being accepted. It is illegal to have | |
98 | //! more than two candidates as the compiler has no method by which to resolve | |
99 | //! this conflict. Additionally, rlib/dylib candidates are considered | |
100 | //! separately. | |
101 | //! | |
102 | //! After all this has happened, we have 1 or two files as candidates. These | |
103 | //! represent the rlib/dylib file found for a library, and they're returned as | |
104 | //! being found. | |
105 | //! | |
106 | //! ### What about versions? | |
107 | //! | |
108 | //! A lot of effort has been put forth to remove versioning from the compiler. | |
109 | //! There have been forays in the past to have versioning baked in, but it was | |
110 | //! largely always deemed insufficient to the point that it was recognized that | |
111 | //! it's probably something the compiler shouldn't do anyway due to its | |
112 | //! complicated nature and the state of the half-baked solutions. | |
113 | //! | |
114 | //! With a departure from versioning, the primary criterion for loading crates | |
115 | //! is just the name of a crate. If we stopped here, it would imply that you | |
116 | //! could never link two crates of the same name from different sources | |
117 | //! together, which is clearly a bad state to be in. | |
118 | //! | |
119 | //! To resolve this problem, we come to the next section! | |
120 | //! | |
121 | //! # Expert Mode | |
122 | //! | |
123 | //! A number of flags have been added to the compiler to solve the "version | |
124 | //! problem" in the previous section, as well as generally enabling more | |
125 | //! powerful usage of the crate loading system of the compiler. The goal of | |
126 | //! these flags and options are to enable third-party tools to drive the | |
127 | //! compiler with prior knowledge about how the world should look. | |
128 | //! | |
129 | //! ## The `--extern` flag | |
130 | //! | |
131 | //! The compiler accepts a flag of this form a number of times: | |
132 | //! | |
133 | //! ```text | |
134 | //! --extern crate-name=path/to/the/crate.rlib | |
135 | //! ``` | |
136 | //! | |
137 | //! This flag is basically the following letter to the compiler: | |
138 | //! | |
139 | //! > Dear rustc, | |
140 | //! > | |
141 | //! > When you are attempting to load the immediate dependency `crate-name`, I | |
9346a6ac | 142 | //! > would like you to assume that the library is located at |
1a4d82fc JJ |
143 | //! > `path/to/the/crate.rlib`, and look nowhere else. Also, please do not |
144 | //! > assume that the path I specified has the name `crate-name`. | |
145 | //! | |
146 | //! This flag basically overrides most matching logic except for validating that | |
147 | //! the file is indeed a rust library. The same `crate-name` can be specified | |
148 | //! twice to specify the rlib/dylib pair. | |
149 | //! | |
150 | //! ## Enabling "multiple versions" | |
151 | //! | |
152 | //! This basically boils down to the ability to specify arbitrary packages to | |
153 | //! the compiler. For example, if crate A wanted to use Bv1 and Bv2, then it | |
154 | //! would look something like: | |
155 | //! | |
041b39d2 | 156 | //! ```compile_fail,E0463 |
1a4d82fc JJ |
157 | //! extern crate b1; |
158 | //! extern crate b2; | |
159 | //! | |
160 | //! fn main() {} | |
161 | //! ``` | |
162 | //! | |
163 | //! and the compiler would be invoked as: | |
164 | //! | |
165 | //! ```text | |
166 | //! rustc a.rs --extern b1=path/to/libb1.rlib --extern b2=path/to/libb2.rlib | |
167 | //! ``` | |
168 | //! | |
169 | //! In this scenario there are two crates named `b` and the compiler must be | |
170 | //! manually driven to be informed where each crate is. | |
171 | //! | |
172 | //! ## Frobbing symbols | |
173 | //! | |
174 | //! One of the immediate problems with linking the same library together twice | |
175 | //! in the same problem is dealing with duplicate symbols. The primary way to | |
176 | //! deal with this in rustc is to add hashes to the end of each symbol. | |
177 | //! | |
178 | //! In order to force hashes to change between versions of a library, if | |
179 | //! desired, the compiler exposes an option `-C metadata=foo`, which is used to | |
180 | //! initially seed each symbol hash. The string `foo` is prepended to each | |
181 | //! string-to-hash to ensure that symbols change over time. | |
182 | //! | |
183 | //! ## Loading transitive dependencies | |
184 | //! | |
185 | //! Dealing with same-named-but-distinct crates is not just a local problem, but | |
186 | //! one that also needs to be dealt with for transitive dependencies. Note that | |
187 | //! in the letter above `--extern` flags only apply to the *local* set of | |
188 | //! dependencies, not the upstream transitive dependencies. Consider this | |
189 | //! dependency graph: | |
190 | //! | |
191 | //! ```text | |
192 | //! A.1 A.2 | |
193 | //! | | | |
194 | //! | | | |
195 | //! B C | |
196 | //! \ / | |
197 | //! \ / | |
198 | //! D | |
199 | //! ``` | |
200 | //! | |
201 | //! In this scenario, when we compile `D`, we need to be able to distinctly | |
202 | //! resolve `A.1` and `A.2`, but an `--extern` flag cannot apply to these | |
203 | //! transitive dependencies. | |
204 | //! | |
205 | //! Note that the key idea here is that `B` and `C` are both *already compiled*. | |
206 | //! That is, they have already resolved their dependencies. Due to unrelated | |
207 | //! technical reasons, when a library is compiled, it is only compatible with | |
208 | //! the *exact same* version of the upstream libraries it was compiled against. | |
209 | //! We use the "Strict Version Hash" to identify the exact copy of an upstream | |
210 | //! library. | |
211 | //! | |
212 | //! With this knowledge, we know that `B` and `C` will depend on `A` with | |
213 | //! different SVH values, so we crawl the normal `-L` paths looking for | |
214 | //! `liba*.rlib` and filter based on the contained SVH. | |
215 | //! | |
216 | //! In the end, this ends up not needing `--extern` to specify upstream | |
217 | //! transitive dependencies. | |
218 | //! | |
219 | //! # Wrapping up | |
220 | //! | |
221 | //! That's the general overview of loading crates in the compiler, but it's by | |
222 | //! no means all of the necessary details. Take a look at the rest of | |
c30ab7b3 | 223 | //! metadata::locator or metadata::creader for all the juicy details! |
223e47cc | 224 | |
0531ce1d | 225 | use cstore::{MetadataRef, MetadataBlob}; |
c30ab7b3 SL |
226 | use creader::Library; |
227 | use schema::{METADATA_HEADER, rustc_version}; | |
92a42be0 | 228 | |
54a0048b | 229 | use rustc::hir::svh::Svh; |
7cac9316 | 230 | use rustc::middle::cstore::MetadataLoader; |
476ff2be | 231 | use rustc::session::{config, Session}; |
92a42be0 SL |
232 | use rustc::session::filesearch::{FileSearch, FileMatches, FileDoesntMatch}; |
233 | use rustc::session::search_paths::PathKind; | |
476ff2be | 234 | use rustc::util::nodemap::FxHashMap; |
92a42be0 | 235 | |
3157f602 | 236 | use errors::DiagnosticBuilder; |
476ff2be | 237 | use syntax::symbol::Symbol; |
3157f602 | 238 | use syntax_pos::Span; |
83c7162d | 239 | use rustc_target::spec::{Target, TargetTriple}; |
1a4d82fc | 240 | |
1a4d82fc | 241 | use std::cmp; |
83c7162d | 242 | use std::collections::HashSet; |
a7813a04 | 243 | use std::fmt; |
2c00a5a8 | 244 | use std::fs; |
476ff2be | 245 | use std::io::{self, Read}; |
c34b1796 | 246 | use std::path::{Path, PathBuf}; |
92a42be0 | 247 | use std::time::Instant; |
1a4d82fc | 248 | |
041b39d2 | 249 | use flate2::read::DeflateDecoder; |
1a4d82fc | 250 | |
0531ce1d | 251 | use rustc_data_structures::owning_ref::OwningRef; |
1a4d82fc | 252 | pub struct CrateMismatch { |
c34b1796 | 253 | path: PathBuf, |
1a4d82fc | 254 | got: String, |
223e47cc LB |
255 | } |
256 | ||
1a4d82fc JJ |
257 | pub struct Context<'a> { |
258 | pub sess: &'a Session, | |
259 | pub span: Span, | |
476ff2be SL |
260 | pub ident: Symbol, |
261 | pub crate_name: Symbol, | |
1a4d82fc | 262 | pub hash: Option<&'a Svh>, |
83c7162d | 263 | pub extra_filename: Option<&'a str>, |
85aaf69f SL |
264 | // points to either self.sess.target.target or self.sess.host, must match triple |
265 | pub target: &'a Target, | |
0531ce1d | 266 | pub triple: &'a TargetTriple, |
1a4d82fc JJ |
267 | pub filesearch: FileSearch<'a>, |
268 | pub root: &'a Option<CratePaths>, | |
269 | pub rejected_via_hash: Vec<CrateMismatch>, | |
270 | pub rejected_via_triple: Vec<CrateMismatch>, | |
85aaf69f | 271 | pub rejected_via_kind: Vec<CrateMismatch>, |
a7813a04 | 272 | pub rejected_via_version: Vec<CrateMismatch>, |
476ff2be | 273 | pub rejected_via_filename: Vec<CrateMismatch>, |
1a4d82fc | 274 | pub should_match_name: bool, |
476ff2be | 275 | pub is_proc_macro: Option<bool>, |
8faf50e0 | 276 | pub metadata_loader: &'a dyn MetadataLoader, |
223e47cc LB |
277 | } |
278 | ||
1a4d82fc JJ |
279 | pub struct CratePaths { |
280 | pub ident: String, | |
c34b1796 | 281 | pub dylib: Option<PathBuf>, |
c30ab7b3 | 282 | pub rlib: Option<PathBuf>, |
476ff2be | 283 | pub rmeta: Option<PathBuf>, |
223e47cc LB |
284 | } |
285 | ||
a7813a04 XL |
286 | #[derive(Copy, Clone, PartialEq)] |
287 | enum CrateFlavor { | |
288 | Rlib, | |
476ff2be | 289 | Rmeta, |
c30ab7b3 | 290 | Dylib, |
a7813a04 XL |
291 | } |
292 | ||
293 | impl fmt::Display for CrateFlavor { | |
294 | fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { | |
295 | f.write_str(match *self { | |
296 | CrateFlavor::Rlib => "rlib", | |
476ff2be | 297 | CrateFlavor::Rmeta => "rmeta", |
c30ab7b3 | 298 | CrateFlavor::Dylib => "dylib", |
a7813a04 XL |
299 | }) |
300 | } | |
301 | } | |
302 | ||
1a4d82fc | 303 | impl CratePaths { |
c34b1796 | 304 | fn paths(&self) -> Vec<PathBuf> { |
476ff2be | 305 | self.dylib.iter().chain(self.rlib.iter()).chain(self.rmeta.iter()).cloned().collect() |
1a4d82fc JJ |
306 | } |
307 | } | |
308 | ||
309 | impl<'a> Context<'a> { | |
310 | pub fn maybe_load_library_crate(&mut self) -> Option<Library> { | |
83c7162d XL |
311 | let mut seen_paths = HashSet::new(); |
312 | match self.extra_filename { | |
313 | Some(s) => self.find_library_crate(s, &mut seen_paths) | |
314 | .or_else(|| self.find_library_crate("", &mut seen_paths)), | |
315 | None => self.find_library_crate("", &mut seen_paths) | |
316 | } | |
1a4d82fc JJ |
317 | } |
318 | ||
c30ab7b3 | 319 | pub fn report_errs(&mut self) -> ! { |
b039eaaf SL |
320 | let add = match self.root { |
321 | &None => String::new(), | |
c30ab7b3 | 322 | &Some(ref r) => format!(" which `{}` depends on", r.ident), |
b039eaaf | 323 | }; |
ff7c6d11 | 324 | let mut msg = "the following crate versions were found:".to_string(); |
9cc50fc6 | 325 | let mut err = if !self.rejected_via_hash.is_empty() { |
c30ab7b3 SL |
326 | let mut err = struct_span_err!(self.sess, |
327 | self.span, | |
ff7c6d11 XL |
328 | E0460, |
329 | "found possibly newer version of crate `{}`{}", | |
c30ab7b3 SL |
330 | self.ident, |
331 | add); | |
a7813a04 | 332 | err.note("perhaps that crate needs to be recompiled?"); |
1a4d82fc | 333 | let mismatches = self.rejected_via_hash.iter(); |
ff7c6d11 XL |
334 | for &CrateMismatch { ref path, .. } in mismatches { |
335 | msg.push_str(&format!("\ncrate `{}`: {}", self.ident, path.display())); | |
1a4d82fc JJ |
336 | } |
337 | match self.root { | |
338 | &None => {} | |
339 | &Some(ref r) => { | |
ff7c6d11 XL |
340 | for path in r.paths().iter() { |
341 | msg.push_str(&format!("\ncrate `{}`: {}", r.ident, path.display())); | |
970d7e83 | 342 | } |
223e47cc | 343 | } |
223e47cc | 344 | } |
ff7c6d11 XL |
345 | err.note(&msg); |
346 | err | |
347 | } else if !self.rejected_via_triple.is_empty() { | |
348 | let mut err = struct_span_err!(self.sess, | |
349 | self.span, | |
350 | E0461, | |
351 | "couldn't find crate `{}` \ | |
352 | with expected target triple {}{}", | |
353 | self.ident, | |
354 | self.triple, | |
355 | add); | |
356 | let mismatches = self.rejected_via_triple.iter(); | |
357 | for &CrateMismatch { ref path, ref got } in mismatches { | |
358 | msg.push_str(&format!("\ncrate `{}`, target triple {}: {}", | |
359 | self.ident, | |
360 | got, | |
361 | path.display())); | |
362 | } | |
363 | err.note(&msg); | |
364 | err | |
365 | } else if !self.rejected_via_kind.is_empty() { | |
366 | let mut err = struct_span_err!(self.sess, | |
367 | self.span, | |
368 | E0462, | |
369 | "found staticlib `{}` instead of rlib or dylib{}", | |
370 | self.ident, | |
371 | add); | |
a7813a04 | 372 | err.help("please recompile that crate using --crate-type lib"); |
85aaf69f | 373 | let mismatches = self.rejected_via_kind.iter(); |
ff7c6d11 XL |
374 | for &CrateMismatch { ref path, .. } in mismatches { |
375 | msg.push_str(&format!("\ncrate `{}`: {}", self.ident, path.display())); | |
a7813a04 | 376 | } |
ff7c6d11 XL |
377 | err.note(&msg); |
378 | err | |
379 | } else if !self.rejected_via_version.is_empty() { | |
380 | let mut err = struct_span_err!(self.sess, | |
381 | self.span, | |
382 | E0514, | |
383 | "found crate `{}` compiled by an incompatible version \ | |
384 | of rustc{}", | |
385 | self.ident, | |
386 | add); | |
a7813a04 | 387 | err.help(&format!("please recompile that crate using this compiler ({})", |
c30ab7b3 | 388 | rustc_version())); |
a7813a04 | 389 | let mismatches = self.rejected_via_version.iter(); |
ff7c6d11 XL |
390 | for &CrateMismatch { ref path, ref got } in mismatches { |
391 | msg.push_str(&format!("\ncrate `{}` compiled by {}: {}", | |
392 | self.ident, | |
393 | got, | |
394 | path.display())); | |
85aaf69f | 395 | } |
ff7c6d11 XL |
396 | err.note(&msg); |
397 | err | |
398 | } else { | |
399 | let mut err = struct_span_err!(self.sess, | |
400 | self.span, | |
401 | E0463, | |
402 | "can't find crate for `{}`{}", | |
403 | self.ident, | |
404 | add); | |
405 | ||
406 | if (self.ident == "std" || self.ident == "core") | |
0531ce1d | 407 | && self.triple != &TargetTriple::from_triple(config::host_triple()) { |
ff7c6d11 XL |
408 | err.note(&format!("the `{}` target may not be installed", self.triple)); |
409 | } | |
410 | err.span_label(self.span, "can't find crate"); | |
411 | err | |
412 | }; | |
413 | ||
476ff2be SL |
414 | if !self.rejected_via_filename.is_empty() { |
415 | let dylibname = self.dylibname(); | |
416 | let mismatches = self.rejected_via_filename.iter(); | |
417 | for &CrateMismatch { ref path, .. } in mismatches { | |
418 | err.note(&format!("extern location for {} is of an unknown type: {}", | |
419 | self.crate_name, | |
420 | path.display())) | |
421 | .help(&format!("file name should be lib*.rlib or {}*.{}", | |
422 | dylibname.0, | |
423 | dylibname.1)); | |
424 | } | |
425 | } | |
9cc50fc6 SL |
426 | |
427 | err.emit(); | |
1a4d82fc | 428 | self.sess.abort_if_errors(); |
54a0048b | 429 | unreachable!(); |
1a4d82fc JJ |
430 | } |
431 | ||
83c7162d XL |
432 | fn find_library_crate(&mut self, |
433 | extra_prefix: &str, | |
434 | seen_paths: &mut HashSet<PathBuf>) | |
435 | -> Option<Library> { | |
1a4d82fc JJ |
436 | // If an SVH is specified, then this is a transitive dependency that |
437 | // must be loaded via -L plus some filtering. | |
438 | if self.hash.is_none() { | |
439 | self.should_match_name = false; | |
476ff2be | 440 | if let Some(s) = self.sess.opts.externs.get(&self.crate_name.as_str()) { |
5bcae85e | 441 | return self.find_commandline_library(s.iter()); |
1a4d82fc JJ |
442 | } |
443 | self.should_match_name = true; | |
444 | } | |
445 | ||
446 | let dypair = self.dylibname(); | |
7453a54e | 447 | let staticpair = self.staticlibname(); |
1a4d82fc JJ |
448 | |
449 | // want: crate_name.dir_part() + prefix + crate_name.file_part + "-" | |
83c7162d XL |
450 | let dylib_prefix = format!("{}{}{}", dypair.0, self.crate_name, extra_prefix); |
451 | let rlib_prefix = format!("lib{}{}", self.crate_name, extra_prefix); | |
452 | let staticlib_prefix = format!("{}{}{}", staticpair.0, self.crate_name, extra_prefix); | |
1a4d82fc | 453 | |
476ff2be | 454 | let mut candidates = FxHashMap(); |
c30ab7b3 | 455 | let mut staticlibs = vec![]; |
1a4d82fc JJ |
456 | |
457 | // First, find all possible candidate rlibs and dylibs purely based on | |
458 | // the name of the files themselves. We're trying to match against an | |
459 | // exact crate name and a possibly an exact hash. | |
460 | // | |
461 | // During this step, we can filter all found libraries based on the | |
462 | // name and id found in the crate id (we ignore the path portion for | |
463 | // filename matching), as well as the exact hash (if specified). If we | |
464 | // end up having many candidates, we must look at the metadata to | |
465 | // perform exact matches against hashes/crate ids. Note that opening up | |
466 | // the metadata is where we do an exact match against the full contents | |
467 | // of the crate id (path/name/id). | |
468 | // | |
469 | // The goal of this step is to look at as little metadata as possible. | |
85aaf69f | 470 | self.filesearch.search(|path, kind| { |
c34b1796 | 471 | let file = match path.file_name().and_then(|s| s.to_str()) { |
1a4d82fc JJ |
472 | None => return FileDoesntMatch, |
473 | Some(file) => file, | |
474 | }; | |
476ff2be | 475 | let (hash, found_kind) = |
cc61c64b | 476 | if file.starts_with(&rlib_prefix) && file.ends_with(".rlib") { |
476ff2be | 477 | (&file[(rlib_prefix.len())..(file.len() - ".rlib".len())], CrateFlavor::Rlib) |
cc61c64b | 478 | } else if file.starts_with(&rlib_prefix) && file.ends_with(".rmeta") { |
476ff2be SL |
479 | (&file[(rlib_prefix.len())..(file.len() - ".rmeta".len())], CrateFlavor::Rmeta) |
480 | } else if file.starts_with(&dylib_prefix) && | |
481 | file.ends_with(&dypair.1) { | |
482 | (&file[(dylib_prefix.len())..(file.len() - dypair.1.len())], CrateFlavor::Dylib) | |
483 | } else { | |
cc61c64b | 484 | if file.starts_with(&staticlib_prefix) && file.ends_with(&staticpair.1) { |
476ff2be SL |
485 | staticlibs.push(CrateMismatch { |
486 | path: path.to_path_buf(), | |
487 | got: "static".to_string(), | |
488 | }); | |
489 | } | |
490 | return FileDoesntMatch; | |
491 | }; | |
83c7162d | 492 | |
1a4d82fc JJ |
493 | info!("lib candidate: {}", path.display()); |
494 | ||
495 | let hash_str = hash.to_string(); | |
c34b1796 | 496 | let slot = candidates.entry(hash_str) |
476ff2be SL |
497 | .or_insert_with(|| (FxHashMap(), FxHashMap(), FxHashMap())); |
498 | let (ref mut rlibs, ref mut rmetas, ref mut dylibs) = *slot; | |
c30ab7b3 SL |
499 | fs::canonicalize(path) |
500 | .map(|p| { | |
83c7162d XL |
501 | if seen_paths.contains(&p) { |
502 | return FileDoesntMatch | |
503 | }; | |
504 | seen_paths.insert(p.clone()); | |
476ff2be SL |
505 | match found_kind { |
506 | CrateFlavor::Rlib => { rlibs.insert(p, kind); } | |
507 | CrateFlavor::Rmeta => { rmetas.insert(p, kind); } | |
508 | CrateFlavor::Dylib => { dylibs.insert(p, kind); } | |
c30ab7b3 SL |
509 | } |
510 | FileMatches | |
511 | }) | |
512 | .unwrap_or(FileDoesntMatch) | |
1a4d82fc | 513 | }); |
62682a34 | 514 | self.rejected_via_kind.extend(staticlibs); |
1a4d82fc JJ |
515 | |
516 | // We have now collected all known libraries into a set of candidates | |
517 | // keyed of the filename hash listed. For each filename, we also have a | |
518 | // list of rlibs/dylibs that apply. Here, we map each of these lists | |
519 | // (per hash), to a Library candidate for returning. | |
520 | // | |
521 | // A Library candidate is created if the metadata for the set of | |
522 | // libraries corresponds to the crate id and hash criteria that this | |
523 | // search is being performed for. | |
476ff2be SL |
524 | let mut libraries = FxHashMap(); |
525 | for (_hash, (rlibs, rmetas, dylibs)) in candidates { | |
a7813a04 XL |
526 | let mut slot = None; |
527 | let rlib = self.extract_one(rlibs, CrateFlavor::Rlib, &mut slot); | |
476ff2be | 528 | let rmeta = self.extract_one(rmetas, CrateFlavor::Rmeta, &mut slot); |
a7813a04 XL |
529 | let dylib = self.extract_one(dylibs, CrateFlavor::Dylib, &mut slot); |
530 | if let Some((h, m)) = slot { | |
c30ab7b3 SL |
531 | libraries.insert(h, |
532 | Library { | |
3b2f2976 XL |
533 | dylib, |
534 | rlib, | |
535 | rmeta, | |
c30ab7b3 SL |
536 | metadata: m, |
537 | }); | |
1a4d82fc JJ |
538 | } |
539 | } | |
540 | ||
541 | // Having now translated all relevant found hashes into libraries, see | |
542 | // what we've got and figure out if we found multiple candidates for | |
543 | // libraries or not. | |
544 | match libraries.len() { | |
545 | 0 => None, | |
a7813a04 | 546 | 1 => Some(libraries.into_iter().next().unwrap().1), |
970d7e83 | 547 | _ => { |
c30ab7b3 SL |
548 | let mut err = struct_span_err!(self.sess, |
549 | self.span, | |
550 | E0464, | |
9cc50fc6 SL |
551 | "multiple matching crates for `{}`", |
552 | self.crate_name); | |
ff7c6d11 XL |
553 | let candidates = libraries.iter().filter_map(|(_, lib)| { |
554 | let crate_name = &lib.metadata.get_root().name.as_str(); | |
555 | match &(&lib.dylib, &lib.rlib) { | |
556 | &(&Some((ref pd, _)), &Some((ref pr, _))) => { | |
557 | Some(format!("\ncrate `{}`: {}\n{:>padding$}", | |
558 | crate_name, | |
559 | pd.display(), | |
560 | pr.display(), | |
561 | padding=8 + crate_name.len())) | |
562 | } | |
563 | &(&Some((ref p, _)), &None) | &(&None, &Some((ref p, _))) => { | |
564 | Some(format!("\ncrate `{}`: {}", crate_name, p.display())) | |
565 | } | |
566 | &(&None, &None) => None, | |
1a4d82fc | 567 | } |
ff7c6d11 XL |
568 | }).collect::<String>(); |
569 | err.note(&format!("candidates:{}", candidates)); | |
9cc50fc6 | 570 | err.emit(); |
970d7e83 LB |
571 | None |
572 | } | |
1a4d82fc JJ |
573 | } |
574 | } | |
575 | ||
576 | // Attempts to extract *one* library from the set `m`. If the set has no | |
577 | // elements, `None` is returned. If the set has more than one element, then | |
578 | // the errors and notes are emitted about the set of libraries. | |
579 | // | |
580 | // With only one library in the set, this function will extract it, and then | |
581 | // read the metadata from it if `*slot` is `None`. If the metadata couldn't | |
582 | // be read, it is assumed that the file isn't a valid rust library (no | |
583 | // errors are emitted). | |
c30ab7b3 | 584 | fn extract_one(&mut self, |
476ff2be | 585 | m: FxHashMap<PathBuf, PathKind>, |
c30ab7b3 SL |
586 | flavor: CrateFlavor, |
587 | slot: &mut Option<(Svh, MetadataBlob)>) | |
588 | -> Option<(PathBuf, PathKind)> { | |
a7813a04 | 589 | let mut ret: Option<(PathBuf, PathKind)> = None; |
85aaf69f | 590 | let mut error = 0; |
1a4d82fc JJ |
591 | |
592 | if slot.is_some() { | |
593 | // FIXME(#10786): for an optimization, we only read one of the | |
a7813a04 | 594 | // libraries' metadata sections. In theory we should |
1a4d82fc JJ |
595 | // read both, but reading dylib metadata is quite |
596 | // slow. | |
9346a6ac | 597 | if m.is_empty() { |
c30ab7b3 | 598 | return None; |
1a4d82fc | 599 | } else if m.len() == 1 { |
c30ab7b3 | 600 | return Some(m.into_iter().next().unwrap()); |
1a4d82fc JJ |
601 | } |
602 | } | |
603 | ||
9cc50fc6 | 604 | let mut err: Option<DiagnosticBuilder> = None; |
85aaf69f | 605 | for (lib, kind) in m { |
1a4d82fc | 606 | info!("{} reading metadata from: {}", flavor, lib.display()); |
7cac9316 XL |
607 | let (hash, metadata) = |
608 | match get_metadata_section(self.target, flavor, &lib, self.metadata_loader) { | |
609 | Ok(blob) => { | |
610 | if let Some(h) = self.crate_matches(&blob, &lib) { | |
611 | (h, blob) | |
612 | } else { | |
613 | info!("metadata mismatch"); | |
614 | continue; | |
615 | } | |
616 | } | |
617 | Err(err) => { | |
618 | info!("no metadata found: {}", err); | |
c30ab7b3 | 619 | continue; |
1a4d82fc | 620 | } |
7cac9316 | 621 | }; |
a7813a04 XL |
622 | // If we see multiple hashes, emit an error about duplicate candidates. |
623 | if slot.as_ref().map_or(false, |s| s.0 != hash) { | |
c30ab7b3 SL |
624 | let mut e = struct_span_err!(self.sess, |
625 | self.span, | |
626 | E0465, | |
9cc50fc6 | 627 | "multiple {} candidates for `{}` found", |
c30ab7b3 SL |
628 | flavor, |
629 | self.crate_name); | |
9cc50fc6 SL |
630 | e.span_note(self.span, |
631 | &format!(r"candidate #1: {}", | |
c30ab7b3 SL |
632 | ret.as_ref() |
633 | .unwrap() | |
634 | .0 | |
635 | .display())); | |
9cc50fc6 SL |
636 | if let Some(ref mut e) = err { |
637 | e.emit(); | |
638 | } | |
639 | err = Some(e); | |
1a4d82fc | 640 | error = 1; |
a7813a04 | 641 | *slot = None; |
1a4d82fc JJ |
642 | } |
643 | if error > 0 { | |
644 | error += 1; | |
9cc50fc6 | 645 | err.as_mut().unwrap().span_note(self.span, |
c30ab7b3 SL |
646 | &format!(r"candidate #{}: {}", |
647 | error, | |
9cc50fc6 | 648 | lib.display())); |
c30ab7b3 | 649 | continue; |
970d7e83 | 650 | } |
8bb4bdeb XL |
651 | |
652 | // Ok so at this point we've determined that `(lib, kind)` above is | |
653 | // a candidate crate to load, and that `slot` is either none (this | |
654 | // is the first crate of its kind) or if some the previous path has | |
655 | // the exact same hash (e.g. it's the exact same crate). | |
656 | // | |
657 | // In principle these two candidate crates are exactly the same so | |
658 | // we can choose either of them to link. As a stupidly gross hack, | |
659 | // however, we favor crate in the sysroot. | |
660 | // | |
661 | // You can find more info in rust-lang/rust#39518 and various linked | |
662 | // issues, but the general gist is that during testing libstd the | |
663 | // compilers has two candidates to choose from: one in the sysroot | |
664 | // and one in the deps folder. These two crates are the exact same | |
665 | // crate but if the compiler chooses the one in the deps folder | |
666 | // it'll cause spurious errors on Windows. | |
667 | // | |
668 | // As a result, we favor the sysroot crate here. Note that the | |
669 | // candidates are all canonicalized, so we canonicalize the sysroot | |
670 | // as well. | |
671 | if let Some((ref prev, _)) = ret { | |
672 | let sysroot = self.sess.sysroot(); | |
673 | let sysroot = sysroot.canonicalize() | |
674 | .unwrap_or(sysroot.to_path_buf()); | |
675 | if prev.starts_with(&sysroot) { | |
676 | continue | |
677 | } | |
678 | } | |
a7813a04 | 679 | *slot = Some((hash, metadata)); |
85aaf69f | 680 | ret = Some((lib, kind)); |
1a4d82fc | 681 | } |
9cc50fc6 SL |
682 | |
683 | if error > 0 { | |
684 | err.unwrap().emit(); | |
685 | None | |
686 | } else { | |
687 | ret | |
688 | } | |
1a4d82fc JJ |
689 | } |
690 | ||
9e0c209e | 691 | fn crate_matches(&mut self, metadata: &MetadataBlob, libpath: &Path) -> Option<Svh> { |
c30ab7b3 | 692 | let rustc_version = rustc_version(); |
476ff2be SL |
693 | let found_version = metadata.get_rustc_version(); |
694 | if found_version != rustc_version { | |
9e0c209e | 695 | info!("Rejecting via version: expected {} got {}", |
c30ab7b3 | 696 | rustc_version, |
476ff2be | 697 | found_version); |
a7813a04 XL |
698 | self.rejected_via_version.push(CrateMismatch { |
699 | path: libpath.to_path_buf(), | |
476ff2be | 700 | got: found_version, |
a7813a04 XL |
701 | }); |
702 | return None; | |
703 | } | |
704 | ||
476ff2be SL |
705 | let root = metadata.get_root(); |
706 | if let Some(is_proc_macro) = self.is_proc_macro { | |
707 | if root.macro_derive_registrar.is_some() != is_proc_macro { | |
708 | return None; | |
709 | } | |
710 | } | |
711 | ||
1a4d82fc | 712 | if self.should_match_name { |
9e0c209e | 713 | if self.crate_name != root.name { |
c30ab7b3 SL |
714 | info!("Rejecting via crate name"); |
715 | return None; | |
1a4d82fc JJ |
716 | } |
717 | } | |
1a4d82fc | 718 | |
0531ce1d | 719 | if &root.triple != self.triple { |
9e0c209e | 720 | info!("Rejecting via crate triple: expected {} got {}", |
c30ab7b3 SL |
721 | self.triple, |
722 | root.triple); | |
1a4d82fc | 723 | self.rejected_via_triple.push(CrateMismatch { |
c34b1796 | 724 | path: libpath.to_path_buf(), |
8faf50e0 | 725 | got: root.triple.to_string(), |
1a4d82fc | 726 | }); |
a7813a04 | 727 | return None; |
223e47cc | 728 | } |
223e47cc | 729 | |
a7813a04 | 730 | if let Some(myhash) = self.hash { |
9e0c209e | 731 | if *myhash != root.hash { |
c30ab7b3 | 732 | info!("Rejecting via hash: expected {} got {}", *myhash, root.hash); |
a7813a04 XL |
733 | self.rejected_via_hash.push(CrateMismatch { |
734 | path: libpath.to_path_buf(), | |
c30ab7b3 | 735 | got: myhash.to_string(), |
a7813a04 XL |
736 | }); |
737 | return None; | |
1a4d82fc | 738 | } |
223e47cc | 739 | } |
a7813a04 | 740 | |
9e0c209e | 741 | Some(root.hash) |
223e47cc | 742 | } |
223e47cc | 743 | |
1a4d82fc JJ |
744 | |
745 | // Returns the corresponding (prefix, suffix) that files need to have for | |
746 | // dynamic libraries | |
747 | fn dylibname(&self) -> (String, String) { | |
85aaf69f | 748 | let t = &self.target; |
1a4d82fc | 749 | (t.options.dll_prefix.clone(), t.options.dll_suffix.clone()) |
223e47cc | 750 | } |
223e47cc | 751 | |
7453a54e SL |
752 | // Returns the corresponding (prefix, suffix) that files need to have for |
753 | // static libraries | |
754 | fn staticlibname(&self) -> (String, String) { | |
755 | let t = &self.target; | |
756 | (t.options.staticlib_prefix.clone(), t.options.staticlib_suffix.clone()) | |
757 | } | |
758 | ||
c30ab7b3 SL |
759 | fn find_commandline_library<'b, LOCS>(&mut self, locs: LOCS) -> Option<Library> |
760 | where LOCS: Iterator<Item = &'b String> | |
5bcae85e | 761 | { |
1a4d82fc JJ |
762 | // First, filter out all libraries that look suspicious. We only accept |
763 | // files which actually exist that have the correct naming scheme for | |
764 | // rlibs/dylibs. | |
765 | let sess = self.sess; | |
766 | let dylibname = self.dylibname(); | |
476ff2be SL |
767 | let mut rlibs = FxHashMap(); |
768 | let mut rmetas = FxHashMap(); | |
769 | let mut dylibs = FxHashMap(); | |
1a4d82fc | 770 | { |
5bcae85e | 771 | let locs = locs.map(|l| PathBuf::from(l)).filter(|loc| { |
1a4d82fc JJ |
772 | if !loc.exists() { |
773 | sess.err(&format!("extern location for {} does not exist: {}", | |
c30ab7b3 SL |
774 | self.crate_name, |
775 | loc.display())); | |
1a4d82fc JJ |
776 | return false; |
777 | } | |
c34b1796 | 778 | let file = match loc.file_name().and_then(|s| s.to_str()) { |
1a4d82fc JJ |
779 | Some(file) => file, |
780 | None => { | |
781 | sess.err(&format!("extern location for {} is not a file: {}", | |
c30ab7b3 SL |
782 | self.crate_name, |
783 | loc.display())); | |
1a4d82fc JJ |
784 | return false; |
785 | } | |
786 | }; | |
476ff2be SL |
787 | if file.starts_with("lib") && |
788 | (file.ends_with(".rlib") || file.ends_with(".rmeta")) { | |
c30ab7b3 | 789 | return true; |
1a4d82fc JJ |
790 | } else { |
791 | let (ref prefix, ref suffix) = dylibname; | |
c30ab7b3 SL |
792 | if file.starts_with(&prefix[..]) && file.ends_with(&suffix[..]) { |
793 | return true; | |
1a4d82fc JJ |
794 | } |
795 | } | |
476ff2be SL |
796 | |
797 | self.rejected_via_filename.push(CrateMismatch { | |
798 | path: loc.clone(), | |
799 | got: String::new(), | |
800 | }); | |
801 | ||
1a4d82fc JJ |
802 | false |
803 | }); | |
804 | ||
85aaf69f SL |
805 | // Now that we have an iterator of good candidates, make sure |
806 | // there's at most one rlib and at most one dylib. | |
1a4d82fc | 807 | for loc in locs { |
c34b1796 | 808 | if loc.file_name().unwrap().to_str().unwrap().ends_with(".rlib") { |
c30ab7b3 | 809 | rlibs.insert(fs::canonicalize(&loc).unwrap(), PathKind::ExternFlag); |
476ff2be SL |
810 | } else if loc.file_name().unwrap().to_str().unwrap().ends_with(".rmeta") { |
811 | rmetas.insert(fs::canonicalize(&loc).unwrap(), PathKind::ExternFlag); | |
1a4d82fc | 812 | } else { |
c30ab7b3 | 813 | dylibs.insert(fs::canonicalize(&loc).unwrap(), PathKind::ExternFlag); |
1a4d82fc JJ |
814 | } |
815 | } | |
816 | }; | |
817 | ||
818 | // Extract the rlib/dylib pair. | |
a7813a04 XL |
819 | let mut slot = None; |
820 | let rlib = self.extract_one(rlibs, CrateFlavor::Rlib, &mut slot); | |
476ff2be | 821 | let rmeta = self.extract_one(rmetas, CrateFlavor::Rmeta, &mut slot); |
a7813a04 | 822 | let dylib = self.extract_one(dylibs, CrateFlavor::Dylib, &mut slot); |
1a4d82fc | 823 | |
476ff2be | 824 | if rlib.is_none() && rmeta.is_none() && dylib.is_none() { |
c30ab7b3 SL |
825 | return None; |
826 | } | |
8faf50e0 XL |
827 | slot.map(|(_, metadata)| |
828 | Library { | |
829 | dylib, | |
830 | rlib, | |
831 | rmeta, | |
832 | metadata, | |
c30ab7b3 | 833 | } |
8faf50e0 | 834 | ) |
223e47cc | 835 | } |
223e47cc LB |
836 | } |
837 | ||
1a4d82fc | 838 | // Just a small wrapper to time how long reading metadata takes. |
c30ab7b3 SL |
839 | fn get_metadata_section(target: &Target, |
840 | flavor: CrateFlavor, | |
7cac9316 | 841 | filename: &Path, |
8faf50e0 | 842 | loader: &dyn MetadataLoader) |
62682a34 | 843 | -> Result<MetadataBlob, String> { |
92a42be0 | 844 | let start = Instant::now(); |
7cac9316 | 845 | let ret = get_metadata_section_imp(target, flavor, filename, loader); |
c30ab7b3 SL |
846 | info!("reading {:?} => {:?}", |
847 | filename.file_name().unwrap(), | |
92a42be0 | 848 | start.elapsed()); |
c30ab7b3 | 849 | return ret; |
223e47cc LB |
850 | } |
851 | ||
c30ab7b3 SL |
852 | fn get_metadata_section_imp(target: &Target, |
853 | flavor: CrateFlavor, | |
7cac9316 | 854 | filename: &Path, |
8faf50e0 | 855 | loader: &dyn MetadataLoader) |
62682a34 | 856 | -> Result<MetadataBlob, String> { |
1a4d82fc JJ |
857 | if !filename.exists() { |
858 | return Err(format!("no such file: '{}'", filename.display())); | |
859 | } | |
0531ce1d | 860 | let raw_bytes: MetadataRef = match flavor { |
7cac9316 XL |
861 | CrateFlavor::Rlib => loader.get_rlib_metadata(target, filename)?, |
862 | CrateFlavor::Dylib => { | |
863 | let buf = loader.get_dylib_metadata(target, filename)?; | |
864 | // The header is uncompressed | |
865 | let header_len = METADATA_HEADER.len(); | |
866 | debug!("checking {} bytes of metadata-version stamp", header_len); | |
867 | let header = &buf[..cmp::min(header_len, buf.len())]; | |
868 | if header != METADATA_HEADER { | |
869 | return Err(format!("incompatible metadata version found: '{}'", | |
870 | filename.display())); | |
1a4d82fc | 871 | } |
223e47cc | 872 | |
7cac9316 XL |
873 | // Header is okay -> inflate the actual metadata |
874 | let compressed_bytes = &buf[header_len..]; | |
875 | debug!("inflating {} bytes of compressed metadata", compressed_bytes.len()); | |
041b39d2 XL |
876 | let mut inflated = Vec::new(); |
877 | match DeflateDecoder::new(compressed_bytes).read_to_end(&mut inflated) { | |
878 | Ok(_) => { | |
7cac9316 | 879 | let buf = unsafe { OwningRef::new_assert_stable_address(inflated) }; |
0531ce1d | 880 | rustc_erase_owner!(buf.map_owner_box()) |
7cac9316 XL |
881 | } |
882 | Err(_) => { | |
883 | return Err(format!("failed to decompress metadata: {}", filename.display())); | |
223e47cc LB |
884 | } |
885 | } | |
223e47cc | 886 | } |
7cac9316 | 887 | CrateFlavor::Rmeta => { |
2c00a5a8 | 888 | let buf = fs::read(filename).map_err(|_| |
7cac9316 | 889 | format!("failed to read rmeta metadata: '{}'", filename.display()))?; |
0531ce1d | 890 | rustc_erase_owner!(OwningRef::new(buf).map_owner_box()) |
7cac9316 XL |
891 | } |
892 | }; | |
893 | let blob = MetadataBlob(raw_bytes); | |
894 | if blob.is_compatible() { | |
895 | Ok(blob) | |
1a4d82fc | 896 | } else { |
7cac9316 | 897 | Err(format!("incompatible metadata version found: '{}'", filename.display())) |
223e47cc LB |
898 | } |
899 | } | |
900 | ||
901 | // A diagnostic function for dumping crate metadata to an output stream | |
7cac9316 XL |
902 | pub fn list_file_metadata(target: &Target, |
903 | path: &Path, | |
8faf50e0 XL |
904 | loader: &dyn MetadataLoader, |
905 | out: &mut dyn io::Write) | |
7cac9316 | 906 | -> io::Result<()> { |
a7813a04 | 907 | let filename = path.file_name().unwrap().to_str().unwrap(); |
c30ab7b3 SL |
908 | let flavor = if filename.ends_with(".rlib") { |
909 | CrateFlavor::Rlib | |
476ff2be SL |
910 | } else if filename.ends_with(".rmeta") { |
911 | CrateFlavor::Rmeta | |
c30ab7b3 SL |
912 | } else { |
913 | CrateFlavor::Dylib | |
914 | }; | |
7cac9316 | 915 | match get_metadata_section(target, flavor, path, loader) { |
9e0c209e | 916 | Ok(metadata) => metadata.list_crate_metadata(out), |
c30ab7b3 | 917 | Err(msg) => write!(out, "{}\n", msg), |
223e47cc LB |
918 | } |
919 | } |