923 lines
38 KiB
Rust
923 lines
38 KiB
Rust
// Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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//! Finds crate binaries and loads their metadata
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//!
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//! Might I be the first to welcome you to a world of platform differences,
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//! version requirements, dependency graphs, conflicting desires, and fun! This
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//! is the major guts (along with metadata::creader) of the compiler for loading
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//! crates and resolving dependencies. Let's take a tour!
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//!
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//! # The problem
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//!
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//! Each invocation of the compiler is immediately concerned with one primary
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//! problem, to connect a set of crates to resolved crates on the filesystem.
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//! Concretely speaking, the compiler follows roughly these steps to get here:
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//!
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//! 1. Discover a set of `extern crate` statements.
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//! 2. Transform these directives into crate names. If the directive does not
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//! have an explicit name, then the identifier is the name.
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//! 3. For each of these crate names, find a corresponding crate on the
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//! filesystem.
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//!
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//! Sounds easy, right? Let's walk into some of the nuances.
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//!
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//! ## Transitive Dependencies
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//!
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//! Let's say we've got three crates: A, B, and C. A depends on B, and B depends
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//! on C. When we're compiling A, we primarily need to find and locate B, but we
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//! also end up needing to find and locate C as well.
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//!
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//! The reason for this is that any of B's types could be composed of C's types,
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//! any function in B could return a type from C, etc. To be able to guarantee
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//! that we can always typecheck/translate any function, we have to have
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//! complete knowledge of the whole ecosystem, not just our immediate
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//! dependencies.
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//!
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//! So now as part of the "find a corresponding crate on the filesystem" step
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//! above, this involves also finding all crates for *all upstream
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//! dependencies*. This includes all dependencies transitively.
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//!
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//! ## Rlibs and Dylibs
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//!
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//! The compiler has two forms of intermediate dependencies. These are dubbed
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//! rlibs and dylibs for the static and dynamic variants, respectively. An rlib
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//! is a rustc-defined file format (currently just an ar archive) while a dylib
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//! is a platform-defined dynamic library. Each library has a metadata somewhere
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//! inside of it.
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//!
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//! A third kind of dependency is an rmeta file. These are metadata files and do
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//! not contain any code, etc. To a first approximation, these are treated in the
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//! same way as rlibs. Where there is both an rlib and an rmeta file, the rlib
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//! gets priority (even if the rmeta file is newer). An rmeta file is only
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//! useful for checking a downstream crate, attempting to link one will cause an
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//! error.
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//!
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//! When translating a crate name to a crate on the filesystem, we all of a
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//! sudden need to take into account both rlibs and dylibs! Linkage later on may
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//! use either one of these files, as each has their pros/cons. The job of crate
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//! loading is to discover what's possible by finding all candidates.
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//!
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//! Most parts of this loading systems keep the dylib/rlib as just separate
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//! variables.
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//!
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//! ## Where to look?
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//!
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//! We can't exactly scan your whole hard drive when looking for dependencies,
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//! so we need to places to look. Currently the compiler will implicitly add the
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//! target lib search path ($prefix/lib/rustlib/$target/lib) to any compilation,
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//! and otherwise all -L flags are added to the search paths.
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//!
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//! ## What criterion to select on?
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//!
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//! This a pretty tricky area of loading crates. Given a file, how do we know
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//! whether it's the right crate? Currently, the rules look along these lines:
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//!
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//! 1. Does the filename match an rlib/dylib pattern? That is to say, does the
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//! filename have the right prefix/suffix?
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//! 2. Does the filename have the right prefix for the crate name being queried?
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//! This is filtering for files like `libfoo*.rlib` and such. If the crate
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//! we're looking for was originally compiled with -C extra-filename, the
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//! extra filename will be included in this prefix to reduce reading
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//! metadata from crates that would otherwise share our prefix.
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//! 3. Is the file an actual rust library? This is done by loading the metadata
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//! from the library and making sure it's actually there.
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//! 4. Does the name in the metadata agree with the name of the library?
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//! 5. Does the target in the metadata agree with the current target?
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//! 6. Does the SVH match? (more on this later)
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//!
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//! If the file answers `yes` to all these questions, then the file is
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//! considered as being *candidate* for being accepted. It is illegal to have
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//! more than two candidates as the compiler has no method by which to resolve
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//! this conflict. Additionally, rlib/dylib candidates are considered
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//! separately.
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//!
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//! After all this has happened, we have 1 or two files as candidates. These
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//! represent the rlib/dylib file found for a library, and they're returned as
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//! being found.
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//!
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//! ### What about versions?
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//!
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//! A lot of effort has been put forth to remove versioning from the compiler.
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//! There have been forays in the past to have versioning baked in, but it was
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//! largely always deemed insufficient to the point that it was recognized that
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//! it's probably something the compiler shouldn't do anyway due to its
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//! complicated nature and the state of the half-baked solutions.
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//!
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//! With a departure from versioning, the primary criterion for loading crates
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//! is just the name of a crate. If we stopped here, it would imply that you
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//! could never link two crates of the same name from different sources
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//! together, which is clearly a bad state to be in.
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//!
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//! To resolve this problem, we come to the next section!
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//!
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//! # Expert Mode
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//!
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//! A number of flags have been added to the compiler to solve the "version
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//! problem" in the previous section, as well as generally enabling more
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//! powerful usage of the crate loading system of the compiler. The goal of
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//! these flags and options are to enable third-party tools to drive the
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//! compiler with prior knowledge about how the world should look.
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//!
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//! ## The `--extern` flag
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//!
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//! The compiler accepts a flag of this form a number of times:
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//!
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//! ```text
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//! --extern crate-name=path/to/the/crate.rlib
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//! ```
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//!
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//! This flag is basically the following letter to the compiler:
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//!
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//! > Dear rustc,
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//! >
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//! > When you are attempting to load the immediate dependency `crate-name`, I
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//! > would like you to assume that the library is located at
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//! > `path/to/the/crate.rlib`, and look nowhere else. Also, please do not
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//! > assume that the path I specified has the name `crate-name`.
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//!
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//! This flag basically overrides most matching logic except for validating that
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//! the file is indeed a rust library. The same `crate-name` can be specified
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//! twice to specify the rlib/dylib pair.
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//!
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//! ## Enabling "multiple versions"
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//!
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//! This basically boils down to the ability to specify arbitrary packages to
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//! the compiler. For example, if crate A wanted to use Bv1 and Bv2, then it
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//! would look something like:
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//!
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//! ```compile_fail,E0463
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//! extern crate b1;
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//! extern crate b2;
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//!
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//! fn main() {}
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//! ```
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//!
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//! and the compiler would be invoked as:
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//!
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//! ```text
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//! rustc a.rs --extern b1=path/to/libb1.rlib --extern b2=path/to/libb2.rlib
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//! ```
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//!
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//! In this scenario there are two crates named `b` and the compiler must be
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//! manually driven to be informed where each crate is.
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//!
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//! ## Frobbing symbols
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//!
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//! One of the immediate problems with linking the same library together twice
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//! in the same problem is dealing with duplicate symbols. The primary way to
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//! deal with this in rustc is to add hashes to the end of each symbol.
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//!
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//! In order to force hashes to change between versions of a library, if
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//! desired, the compiler exposes an option `-C metadata=foo`, which is used to
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//! initially seed each symbol hash. The string `foo` is prepended to each
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//! string-to-hash to ensure that symbols change over time.
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//!
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//! ## Loading transitive dependencies
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//!
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//! Dealing with same-named-but-distinct crates is not just a local problem, but
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//! one that also needs to be dealt with for transitive dependencies. Note that
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//! in the letter above `--extern` flags only apply to the *local* set of
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//! dependencies, not the upstream transitive dependencies. Consider this
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//! dependency graph:
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//!
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//! ```text
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//! A.1 A.2
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//! | |
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//! | |
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//! B C
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//! \ /
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//! \ /
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//! D
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//! ```
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//!
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//! In this scenario, when we compile `D`, we need to be able to distinctly
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//! resolve `A.1` and `A.2`, but an `--extern` flag cannot apply to these
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//! transitive dependencies.
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//!
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//! Note that the key idea here is that `B` and `C` are both *already compiled*.
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//! That is, they have already resolved their dependencies. Due to unrelated
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//! technical reasons, when a library is compiled, it is only compatible with
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//! the *exact same* version of the upstream libraries it was compiled against.
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//! We use the "Strict Version Hash" to identify the exact copy of an upstream
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//! library.
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//!
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//! With this knowledge, we know that `B` and `C` will depend on `A` with
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//! different SVH values, so we crawl the normal `-L` paths looking for
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//! `liba*.rlib` and filter based on the contained SVH.
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//!
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//! In the end, this ends up not needing `--extern` to specify upstream
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//! transitive dependencies.
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//!
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//! # Wrapping up
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//!
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//! That's the general overview of loading crates in the compiler, but it's by
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//! no means all of the necessary details. Take a look at the rest of
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//! metadata::locator or metadata::creader for all the juicy details!
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use cstore::{MetadataRef, MetadataBlob};
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use creader::Library;
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use schema::{METADATA_HEADER, rustc_version};
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use rustc::hir::svh::Svh;
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use rustc::middle::cstore::MetadataLoader;
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use rustc::session::{config, Session};
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use rustc::session::filesearch::{FileSearch, FileMatches, FileDoesntMatch};
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use rustc::session::search_paths::PathKind;
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use rustc::util::nodemap::FxHashMap;
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use errors::DiagnosticBuilder;
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use syntax::symbol::Symbol;
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use syntax_pos::Span;
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use rustc_back::target::{Target, TargetTriple};
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use std::cmp;
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use std::collections::HashSet;
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use std::fmt;
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use std::fs;
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use std::io::{self, Read};
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use std::path::{Path, PathBuf};
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use std::time::Instant;
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use flate2::read::DeflateDecoder;
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use rustc_data_structures::owning_ref::OwningRef;
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pub struct CrateMismatch {
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path: PathBuf,
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got: String,
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}
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pub struct Context<'a> {
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pub sess: &'a Session,
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pub span: Span,
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pub ident: Symbol,
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pub crate_name: Symbol,
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pub hash: Option<&'a Svh>,
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pub extra_filename: Option<&'a str>,
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// points to either self.sess.target.target or self.sess.host, must match triple
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pub target: &'a Target,
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pub triple: &'a TargetTriple,
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pub filesearch: FileSearch<'a>,
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pub root: &'a Option<CratePaths>,
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pub rejected_via_hash: Vec<CrateMismatch>,
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pub rejected_via_triple: Vec<CrateMismatch>,
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pub rejected_via_kind: Vec<CrateMismatch>,
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pub rejected_via_version: Vec<CrateMismatch>,
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pub rejected_via_filename: Vec<CrateMismatch>,
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pub should_match_name: bool,
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pub is_proc_macro: Option<bool>,
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pub metadata_loader: &'a MetadataLoader,
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}
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pub struct CratePaths {
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pub ident: String,
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pub dylib: Option<PathBuf>,
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pub rlib: Option<PathBuf>,
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pub rmeta: Option<PathBuf>,
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}
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#[derive(Copy, Clone, PartialEq)]
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enum CrateFlavor {
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Rlib,
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Rmeta,
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Dylib,
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}
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impl fmt::Display for CrateFlavor {
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fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
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f.write_str(match *self {
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CrateFlavor::Rlib => "rlib",
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CrateFlavor::Rmeta => "rmeta",
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CrateFlavor::Dylib => "dylib",
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})
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}
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}
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impl CratePaths {
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fn paths(&self) -> Vec<PathBuf> {
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self.dylib.iter().chain(self.rlib.iter()).chain(self.rmeta.iter()).cloned().collect()
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}
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}
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impl<'a> Context<'a> {
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pub fn maybe_load_library_crate(&mut self) -> Option<Library> {
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let mut seen_paths = HashSet::new();
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match self.extra_filename {
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Some(s) => self.find_library_crate(s, &mut seen_paths)
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.or_else(|| self.find_library_crate("", &mut seen_paths)),
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None => self.find_library_crate("", &mut seen_paths)
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}
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}
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pub fn report_errs(&mut self) -> ! {
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let add = match self.root {
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&None => String::new(),
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&Some(ref r) => format!(" which `{}` depends on", r.ident),
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};
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let mut msg = "the following crate versions were found:".to_string();
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let mut err = if !self.rejected_via_hash.is_empty() {
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let mut err = struct_span_err!(self.sess,
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self.span,
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E0460,
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"found possibly newer version of crate `{}`{}",
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self.ident,
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add);
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err.note("perhaps that crate needs to be recompiled?");
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let mismatches = self.rejected_via_hash.iter();
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for &CrateMismatch { ref path, .. } in mismatches {
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msg.push_str(&format!("\ncrate `{}`: {}", self.ident, path.display()));
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}
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match self.root {
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&None => {}
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&Some(ref r) => {
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for path in r.paths().iter() {
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msg.push_str(&format!("\ncrate `{}`: {}", r.ident, path.display()));
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}
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}
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}
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err.note(&msg);
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err
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} else if !self.rejected_via_triple.is_empty() {
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let mut err = struct_span_err!(self.sess,
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self.span,
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E0461,
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"couldn't find crate `{}` \
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with expected target triple {}{}",
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self.ident,
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self.triple,
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add);
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let mismatches = self.rejected_via_triple.iter();
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for &CrateMismatch { ref path, ref got } in mismatches {
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msg.push_str(&format!("\ncrate `{}`, target triple {}: {}",
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self.ident,
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got,
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path.display()));
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}
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err.note(&msg);
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err
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} else if !self.rejected_via_kind.is_empty() {
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let mut err = struct_span_err!(self.sess,
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self.span,
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E0462,
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"found staticlib `{}` instead of rlib or dylib{}",
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self.ident,
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add);
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err.help("please recompile that crate using --crate-type lib");
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let mismatches = self.rejected_via_kind.iter();
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for &CrateMismatch { ref path, .. } in mismatches {
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msg.push_str(&format!("\ncrate `{}`: {}", self.ident, path.display()));
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}
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err.note(&msg);
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err
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} else if !self.rejected_via_version.is_empty() {
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let mut err = struct_span_err!(self.sess,
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self.span,
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E0514,
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"found crate `{}` compiled by an incompatible version \
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of rustc{}",
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self.ident,
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add);
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err.help(&format!("please recompile that crate using this compiler ({})",
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rustc_version()));
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let mismatches = self.rejected_via_version.iter();
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for &CrateMismatch { ref path, ref got } in mismatches {
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msg.push_str(&format!("\ncrate `{}` compiled by {}: {}",
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self.ident,
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got,
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path.display()));
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}
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err.note(&msg);
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err
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} else {
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let mut err = struct_span_err!(self.sess,
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self.span,
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E0463,
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"can't find crate for `{}`{}",
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self.ident,
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add);
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if (self.ident == "std" || self.ident == "core")
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&& self.triple != &TargetTriple::from_triple(config::host_triple()) {
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err.note(&format!("the `{}` target may not be installed", self.triple));
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}
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err.span_label(self.span, "can't find crate");
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err
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};
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if !self.rejected_via_filename.is_empty() {
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let dylibname = self.dylibname();
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let mismatches = self.rejected_via_filename.iter();
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for &CrateMismatch { ref path, .. } in mismatches {
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err.note(&format!("extern location for {} is of an unknown type: {}",
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self.crate_name,
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path.display()))
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.help(&format!("file name should be lib*.rlib or {}*.{}",
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dylibname.0,
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dylibname.1));
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}
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}
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err.emit();
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self.sess.abort_if_errors();
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unreachable!();
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}
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fn find_library_crate(&mut self,
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extra_prefix: &str,
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seen_paths: &mut HashSet<PathBuf>)
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-> Option<Library> {
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// If an SVH is specified, then this is a transitive dependency that
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// must be loaded via -L plus some filtering.
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if self.hash.is_none() {
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self.should_match_name = false;
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if let Some(s) = self.sess.opts.externs.get(&self.crate_name.as_str()) {
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return self.find_commandline_library(s.iter());
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}
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self.should_match_name = true;
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}
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let dypair = self.dylibname();
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let staticpair = self.staticlibname();
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// want: crate_name.dir_part() + prefix + crate_name.file_part + "-"
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let dylib_prefix = format!("{}{}{}", dypair.0, self.crate_name, extra_prefix);
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let rlib_prefix = format!("lib{}{}", self.crate_name, extra_prefix);
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let staticlib_prefix = format!("{}{}{}", staticpair.0, self.crate_name, extra_prefix);
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let mut candidates = FxHashMap();
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let mut staticlibs = vec![];
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// First, find all possible candidate rlibs and dylibs purely based on
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// the name of the files themselves. We're trying to match against an
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// exact crate name and a possibly an exact hash.
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//
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// During this step, we can filter all found libraries based on the
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// name and id found in the crate id (we ignore the path portion for
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// filename matching), as well as the exact hash (if specified). If we
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// end up having many candidates, we must look at the metadata to
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// perform exact matches against hashes/crate ids. Note that opening up
|
|
// the metadata is where we do an exact match against the full contents
|
|
// of the crate id (path/name/id).
|
|
//
|
|
// The goal of this step is to look at as little metadata as possible.
|
|
self.filesearch.search(|path, kind| {
|
|
let file = match path.file_name().and_then(|s| s.to_str()) {
|
|
None => return FileDoesntMatch,
|
|
Some(file) => file,
|
|
};
|
|
let (hash, found_kind) =
|
|
if file.starts_with(&rlib_prefix) && file.ends_with(".rlib") {
|
|
(&file[(rlib_prefix.len())..(file.len() - ".rlib".len())], CrateFlavor::Rlib)
|
|
} else if file.starts_with(&rlib_prefix) && file.ends_with(".rmeta") {
|
|
(&file[(rlib_prefix.len())..(file.len() - ".rmeta".len())], CrateFlavor::Rmeta)
|
|
} else if file.starts_with(&dylib_prefix) &&
|
|
file.ends_with(&dypair.1) {
|
|
(&file[(dylib_prefix.len())..(file.len() - dypair.1.len())], CrateFlavor::Dylib)
|
|
} else {
|
|
if file.starts_with(&staticlib_prefix) && file.ends_with(&staticpair.1) {
|
|
staticlibs.push(CrateMismatch {
|
|
path: path.to_path_buf(),
|
|
got: "static".to_string(),
|
|
});
|
|
}
|
|
return FileDoesntMatch;
|
|
};
|
|
|
|
info!("lib candidate: {}", path.display());
|
|
|
|
let hash_str = hash.to_string();
|
|
let slot = candidates.entry(hash_str)
|
|
.or_insert_with(|| (FxHashMap(), FxHashMap(), FxHashMap()));
|
|
let (ref mut rlibs, ref mut rmetas, ref mut dylibs) = *slot;
|
|
fs::canonicalize(path)
|
|
.map(|p| {
|
|
if seen_paths.contains(&p) {
|
|
return FileDoesntMatch
|
|
};
|
|
seen_paths.insert(p.clone());
|
|
match found_kind {
|
|
CrateFlavor::Rlib => { rlibs.insert(p, kind); }
|
|
CrateFlavor::Rmeta => { rmetas.insert(p, kind); }
|
|
CrateFlavor::Dylib => { dylibs.insert(p, kind); }
|
|
}
|
|
FileMatches
|
|
})
|
|
.unwrap_or(FileDoesntMatch)
|
|
});
|
|
self.rejected_via_kind.extend(staticlibs);
|
|
|
|
// We have now collected all known libraries into a set of candidates
|
|
// keyed of the filename hash listed. For each filename, we also have a
|
|
// list of rlibs/dylibs that apply. Here, we map each of these lists
|
|
// (per hash), to a Library candidate for returning.
|
|
//
|
|
// A Library candidate is created if the metadata for the set of
|
|
// libraries corresponds to the crate id and hash criteria that this
|
|
// search is being performed for.
|
|
let mut libraries = FxHashMap();
|
|
for (_hash, (rlibs, rmetas, dylibs)) in candidates {
|
|
let mut slot = None;
|
|
let rlib = self.extract_one(rlibs, CrateFlavor::Rlib, &mut slot);
|
|
let rmeta = self.extract_one(rmetas, CrateFlavor::Rmeta, &mut slot);
|
|
let dylib = self.extract_one(dylibs, CrateFlavor::Dylib, &mut slot);
|
|
if let Some((h, m)) = slot {
|
|
libraries.insert(h,
|
|
Library {
|
|
dylib,
|
|
rlib,
|
|
rmeta,
|
|
metadata: m,
|
|
});
|
|
}
|
|
}
|
|
|
|
// Having now translated all relevant found hashes into libraries, see
|
|
// what we've got and figure out if we found multiple candidates for
|
|
// libraries or not.
|
|
match libraries.len() {
|
|
0 => None,
|
|
1 => Some(libraries.into_iter().next().unwrap().1),
|
|
_ => {
|
|
let mut err = struct_span_err!(self.sess,
|
|
self.span,
|
|
E0464,
|
|
"multiple matching crates for `{}`",
|
|
self.crate_name);
|
|
let candidates = libraries.iter().filter_map(|(_, lib)| {
|
|
let crate_name = &lib.metadata.get_root().name.as_str();
|
|
match &(&lib.dylib, &lib.rlib) {
|
|
&(&Some((ref pd, _)), &Some((ref pr, _))) => {
|
|
Some(format!("\ncrate `{}`: {}\n{:>padding$}",
|
|
crate_name,
|
|
pd.display(),
|
|
pr.display(),
|
|
padding=8 + crate_name.len()))
|
|
}
|
|
&(&Some((ref p, _)), &None) | &(&None, &Some((ref p, _))) => {
|
|
Some(format!("\ncrate `{}`: {}", crate_name, p.display()))
|
|
}
|
|
&(&None, &None) => None,
|
|
}
|
|
}).collect::<String>();
|
|
err.note(&format!("candidates:{}", candidates));
|
|
err.emit();
|
|
None
|
|
}
|
|
}
|
|
}
|
|
|
|
// Attempts to extract *one* library from the set `m`. If the set has no
|
|
// elements, `None` is returned. If the set has more than one element, then
|
|
// the errors and notes are emitted about the set of libraries.
|
|
//
|
|
// With only one library in the set, this function will extract it, and then
|
|
// read the metadata from it if `*slot` is `None`. If the metadata couldn't
|
|
// be read, it is assumed that the file isn't a valid rust library (no
|
|
// errors are emitted).
|
|
fn extract_one(&mut self,
|
|
m: FxHashMap<PathBuf, PathKind>,
|
|
flavor: CrateFlavor,
|
|
slot: &mut Option<(Svh, MetadataBlob)>)
|
|
-> Option<(PathBuf, PathKind)> {
|
|
let mut ret: Option<(PathBuf, PathKind)> = None;
|
|
let mut error = 0;
|
|
|
|
if slot.is_some() {
|
|
// FIXME(#10786): for an optimization, we only read one of the
|
|
// libraries' metadata sections. In theory we should
|
|
// read both, but reading dylib metadata is quite
|
|
// slow.
|
|
if m.is_empty() {
|
|
return None;
|
|
} else if m.len() == 1 {
|
|
return Some(m.into_iter().next().unwrap());
|
|
}
|
|
}
|
|
|
|
let mut err: Option<DiagnosticBuilder> = None;
|
|
for (lib, kind) in m {
|
|
info!("{} reading metadata from: {}", flavor, lib.display());
|
|
let (hash, metadata) =
|
|
match get_metadata_section(self.target, flavor, &lib, self.metadata_loader) {
|
|
Ok(blob) => {
|
|
if let Some(h) = self.crate_matches(&blob, &lib) {
|
|
(h, blob)
|
|
} else {
|
|
info!("metadata mismatch");
|
|
continue;
|
|
}
|
|
}
|
|
Err(err) => {
|
|
info!("no metadata found: {}", err);
|
|
continue;
|
|
}
|
|
};
|
|
// If we see multiple hashes, emit an error about duplicate candidates.
|
|
if slot.as_ref().map_or(false, |s| s.0 != hash) {
|
|
let mut e = struct_span_err!(self.sess,
|
|
self.span,
|
|
E0465,
|
|
"multiple {} candidates for `{}` found",
|
|
flavor,
|
|
self.crate_name);
|
|
e.span_note(self.span,
|
|
&format!(r"candidate #1: {}",
|
|
ret.as_ref()
|
|
.unwrap()
|
|
.0
|
|
.display()));
|
|
if let Some(ref mut e) = err {
|
|
e.emit();
|
|
}
|
|
err = Some(e);
|
|
error = 1;
|
|
*slot = None;
|
|
}
|
|
if error > 0 {
|
|
error += 1;
|
|
err.as_mut().unwrap().span_note(self.span,
|
|
&format!(r"candidate #{}: {}",
|
|
error,
|
|
lib.display()));
|
|
continue;
|
|
}
|
|
|
|
// Ok so at this point we've determined that `(lib, kind)` above is
|
|
// a candidate crate to load, and that `slot` is either none (this
|
|
// is the first crate of its kind) or if some the previous path has
|
|
// the exact same hash (e.g. it's the exact same crate).
|
|
//
|
|
// In principle these two candidate crates are exactly the same so
|
|
// we can choose either of them to link. As a stupidly gross hack,
|
|
// however, we favor crate in the sysroot.
|
|
//
|
|
// You can find more info in rust-lang/rust#39518 and various linked
|
|
// issues, but the general gist is that during testing libstd the
|
|
// compilers has two candidates to choose from: one in the sysroot
|
|
// and one in the deps folder. These two crates are the exact same
|
|
// crate but if the compiler chooses the one in the deps folder
|
|
// it'll cause spurious errors on Windows.
|
|
//
|
|
// As a result, we favor the sysroot crate here. Note that the
|
|
// candidates are all canonicalized, so we canonicalize the sysroot
|
|
// as well.
|
|
if let Some((ref prev, _)) = ret {
|
|
let sysroot = self.sess.sysroot();
|
|
let sysroot = sysroot.canonicalize()
|
|
.unwrap_or(sysroot.to_path_buf());
|
|
if prev.starts_with(&sysroot) {
|
|
continue
|
|
}
|
|
}
|
|
*slot = Some((hash, metadata));
|
|
ret = Some((lib, kind));
|
|
}
|
|
|
|
if error > 0 {
|
|
err.unwrap().emit();
|
|
None
|
|
} else {
|
|
ret
|
|
}
|
|
}
|
|
|
|
fn crate_matches(&mut self, metadata: &MetadataBlob, libpath: &Path) -> Option<Svh> {
|
|
let rustc_version = rustc_version();
|
|
let found_version = metadata.get_rustc_version();
|
|
if found_version != rustc_version {
|
|
info!("Rejecting via version: expected {} got {}",
|
|
rustc_version,
|
|
found_version);
|
|
self.rejected_via_version.push(CrateMismatch {
|
|
path: libpath.to_path_buf(),
|
|
got: found_version,
|
|
});
|
|
return None;
|
|
}
|
|
|
|
let root = metadata.get_root();
|
|
if let Some(is_proc_macro) = self.is_proc_macro {
|
|
if root.macro_derive_registrar.is_some() != is_proc_macro {
|
|
return None;
|
|
}
|
|
}
|
|
|
|
if self.should_match_name {
|
|
if self.crate_name != root.name {
|
|
info!("Rejecting via crate name");
|
|
return None;
|
|
}
|
|
}
|
|
|
|
if &root.triple != self.triple {
|
|
info!("Rejecting via crate triple: expected {} got {}",
|
|
self.triple,
|
|
root.triple);
|
|
self.rejected_via_triple.push(CrateMismatch {
|
|
path: libpath.to_path_buf(),
|
|
got: format!("{}", root.triple),
|
|
});
|
|
return None;
|
|
}
|
|
|
|
if let Some(myhash) = self.hash {
|
|
if *myhash != root.hash {
|
|
info!("Rejecting via hash: expected {} got {}", *myhash, root.hash);
|
|
self.rejected_via_hash.push(CrateMismatch {
|
|
path: libpath.to_path_buf(),
|
|
got: myhash.to_string(),
|
|
});
|
|
return None;
|
|
}
|
|
}
|
|
|
|
Some(root.hash)
|
|
}
|
|
|
|
|
|
// Returns the corresponding (prefix, suffix) that files need to have for
|
|
// dynamic libraries
|
|
fn dylibname(&self) -> (String, String) {
|
|
let t = &self.target;
|
|
(t.options.dll_prefix.clone(), t.options.dll_suffix.clone())
|
|
}
|
|
|
|
// Returns the corresponding (prefix, suffix) that files need to have for
|
|
// static libraries
|
|
fn staticlibname(&self) -> (String, String) {
|
|
let t = &self.target;
|
|
(t.options.staticlib_prefix.clone(), t.options.staticlib_suffix.clone())
|
|
}
|
|
|
|
fn find_commandline_library<'b, LOCS>(&mut self, locs: LOCS) -> Option<Library>
|
|
where LOCS: Iterator<Item = &'b String>
|
|
{
|
|
// First, filter out all libraries that look suspicious. We only accept
|
|
// files which actually exist that have the correct naming scheme for
|
|
// rlibs/dylibs.
|
|
let sess = self.sess;
|
|
let dylibname = self.dylibname();
|
|
let mut rlibs = FxHashMap();
|
|
let mut rmetas = FxHashMap();
|
|
let mut dylibs = FxHashMap();
|
|
{
|
|
let locs = locs.map(|l| PathBuf::from(l)).filter(|loc| {
|
|
if !loc.exists() {
|
|
sess.err(&format!("extern location for {} does not exist: {}",
|
|
self.crate_name,
|
|
loc.display()));
|
|
return false;
|
|
}
|
|
let file = match loc.file_name().and_then(|s| s.to_str()) {
|
|
Some(file) => file,
|
|
None => {
|
|
sess.err(&format!("extern location for {} is not a file: {}",
|
|
self.crate_name,
|
|
loc.display()));
|
|
return false;
|
|
}
|
|
};
|
|
if file.starts_with("lib") &&
|
|
(file.ends_with(".rlib") || file.ends_with(".rmeta")) {
|
|
return true;
|
|
} else {
|
|
let (ref prefix, ref suffix) = dylibname;
|
|
if file.starts_with(&prefix[..]) && file.ends_with(&suffix[..]) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
self.rejected_via_filename.push(CrateMismatch {
|
|
path: loc.clone(),
|
|
got: String::new(),
|
|
});
|
|
|
|
false
|
|
});
|
|
|
|
// Now that we have an iterator of good candidates, make sure
|
|
// there's at most one rlib and at most one dylib.
|
|
for loc in locs {
|
|
if loc.file_name().unwrap().to_str().unwrap().ends_with(".rlib") {
|
|
rlibs.insert(fs::canonicalize(&loc).unwrap(), PathKind::ExternFlag);
|
|
} else if loc.file_name().unwrap().to_str().unwrap().ends_with(".rmeta") {
|
|
rmetas.insert(fs::canonicalize(&loc).unwrap(), PathKind::ExternFlag);
|
|
} else {
|
|
dylibs.insert(fs::canonicalize(&loc).unwrap(), PathKind::ExternFlag);
|
|
}
|
|
}
|
|
};
|
|
|
|
// Extract the rlib/dylib pair.
|
|
let mut slot = None;
|
|
let rlib = self.extract_one(rlibs, CrateFlavor::Rlib, &mut slot);
|
|
let rmeta = self.extract_one(rmetas, CrateFlavor::Rmeta, &mut slot);
|
|
let dylib = self.extract_one(dylibs, CrateFlavor::Dylib, &mut slot);
|
|
|
|
if rlib.is_none() && rmeta.is_none() && dylib.is_none() {
|
|
return None;
|
|
}
|
|
match slot {
|
|
Some((_, metadata)) => {
|
|
Some(Library {
|
|
dylib,
|
|
rlib,
|
|
rmeta,
|
|
metadata,
|
|
})
|
|
}
|
|
None => None,
|
|
}
|
|
}
|
|
}
|
|
|
|
// Just a small wrapper to time how long reading metadata takes.
|
|
fn get_metadata_section(target: &Target,
|
|
flavor: CrateFlavor,
|
|
filename: &Path,
|
|
loader: &MetadataLoader)
|
|
-> Result<MetadataBlob, String> {
|
|
let start = Instant::now();
|
|
let ret = get_metadata_section_imp(target, flavor, filename, loader);
|
|
info!("reading {:?} => {:?}",
|
|
filename.file_name().unwrap(),
|
|
start.elapsed());
|
|
return ret;
|
|
}
|
|
|
|
fn get_metadata_section_imp(target: &Target,
|
|
flavor: CrateFlavor,
|
|
filename: &Path,
|
|
loader: &MetadataLoader)
|
|
-> Result<MetadataBlob, String> {
|
|
if !filename.exists() {
|
|
return Err(format!("no such file: '{}'", filename.display()));
|
|
}
|
|
let raw_bytes: MetadataRef = match flavor {
|
|
CrateFlavor::Rlib => loader.get_rlib_metadata(target, filename)?,
|
|
CrateFlavor::Dylib => {
|
|
let buf = loader.get_dylib_metadata(target, filename)?;
|
|
// The header is uncompressed
|
|
let header_len = METADATA_HEADER.len();
|
|
debug!("checking {} bytes of metadata-version stamp", header_len);
|
|
let header = &buf[..cmp::min(header_len, buf.len())];
|
|
if header != METADATA_HEADER {
|
|
return Err(format!("incompatible metadata version found: '{}'",
|
|
filename.display()));
|
|
}
|
|
|
|
// Header is okay -> inflate the actual metadata
|
|
let compressed_bytes = &buf[header_len..];
|
|
debug!("inflating {} bytes of compressed metadata", compressed_bytes.len());
|
|
let mut inflated = Vec::new();
|
|
match DeflateDecoder::new(compressed_bytes).read_to_end(&mut inflated) {
|
|
Ok(_) => {
|
|
let buf = unsafe { OwningRef::new_assert_stable_address(inflated) };
|
|
rustc_erase_owner!(buf.map_owner_box())
|
|
}
|
|
Err(_) => {
|
|
return Err(format!("failed to decompress metadata: {}", filename.display()));
|
|
}
|
|
}
|
|
}
|
|
CrateFlavor::Rmeta => {
|
|
let buf = fs::read(filename).map_err(|_|
|
|
format!("failed to read rmeta metadata: '{}'", filename.display()))?;
|
|
rustc_erase_owner!(OwningRef::new(buf).map_owner_box())
|
|
}
|
|
};
|
|
let blob = MetadataBlob(raw_bytes);
|
|
if blob.is_compatible() {
|
|
Ok(blob)
|
|
} else {
|
|
Err(format!("incompatible metadata version found: '{}'", filename.display()))
|
|
}
|
|
}
|
|
|
|
// A diagnostic function for dumping crate metadata to an output stream
|
|
pub fn list_file_metadata(target: &Target,
|
|
path: &Path,
|
|
loader: &MetadataLoader,
|
|
out: &mut io::Write)
|
|
-> io::Result<()> {
|
|
let filename = path.file_name().unwrap().to_str().unwrap();
|
|
let flavor = if filename.ends_with(".rlib") {
|
|
CrateFlavor::Rlib
|
|
} else if filename.ends_with(".rmeta") {
|
|
CrateFlavor::Rmeta
|
|
} else {
|
|
CrateFlavor::Dylib
|
|
};
|
|
match get_metadata_section(target, flavor, path, loader) {
|
|
Ok(metadata) => metadata.list_crate_metadata(out),
|
|
Err(msg) => write!(out, "{}\n", msg),
|
|
}
|
|
}
|