Vendor things

third-party/vendor/cc/src/tool.rs

@@ -0,0 +1,399 @@
+use std::{
+    collections::HashMap,
+    ffi::OsString,
+    path::{Path, PathBuf},
+    process::Command,
+    sync::Mutex,
+};
+
+use crate::command_helpers::{run_output, CargoOutput};
+
+/// Configuration used to represent an invocation of a C compiler.
+///
+/// This can be used to figure out what compiler is in use, what the arguments
+/// to it are, and what the environment variables look like for the compiler.
+/// This can be used to further configure other build systems (e.g. forward
+/// along CC and/or CFLAGS) or the `to_command` method can be used to run the
+/// compiler itself.
+#[derive(Clone, Debug)]
+#[allow(missing_docs)]
+pub struct Tool {
+    pub(crate) path: PathBuf,
+    pub(crate) cc_wrapper_path: Option<PathBuf>,
+    pub(crate) cc_wrapper_args: Vec<OsString>,
+    pub(crate) args: Vec<OsString>,
+    pub(crate) env: Vec<(OsString, OsString)>,
+    pub(crate) family: ToolFamily,
+    pub(crate) cuda: bool,
+    pub(crate) removed_args: Vec<OsString>,
+    pub(crate) has_internal_target_arg: bool,
+}
+
+impl Tool {
+    pub(crate) fn new(
+        path: PathBuf,
+        cached_compiler_family: &Mutex<HashMap<Box<Path>, ToolFamily>>,
+        cargo_output: &CargoOutput,
+    ) -> Self {
+        Self::with_features(path, None, false, cached_compiler_family, cargo_output)
+    }
+
+    pub(crate) fn with_clang_driver(
+        path: PathBuf,
+        clang_driver: Option<&str>,
+        cached_compiler_family: &Mutex<HashMap<Box<Path>, ToolFamily>>,
+        cargo_output: &CargoOutput,
+    ) -> Self {
+        Self::with_features(
+            path,
+            clang_driver,
+            false,
+            cached_compiler_family,
+            cargo_output,
+        )
+    }
+
+    /// Explicitly set the `ToolFamily`, skipping name-based detection.
+    pub(crate) fn with_family(path: PathBuf, family: ToolFamily) -> Self {
+        Self {
+            path,
+            cc_wrapper_path: None,
+            cc_wrapper_args: Vec::new(),
+            args: Vec::new(),
+            env: Vec::new(),
+            family,
+            cuda: false,
+            removed_args: Vec::new(),
+            has_internal_target_arg: false,
+        }
+    }
+
+    pub(crate) fn with_features(
+        path: PathBuf,
+        clang_driver: Option<&str>,
+        cuda: bool,
+        cached_compiler_family: &Mutex<HashMap<Box<Path>, ToolFamily>>,
+        cargo_output: &CargoOutput,
+    ) -> Self {
+        fn detect_family_inner(path: &Path, cargo_output: &CargoOutput) -> ToolFamily {
+            let mut cmd = Command::new(path);
+            cmd.arg("--version");
+
+            let stdout = match run_output(
+                &mut cmd,
+                &path.to_string_lossy(),
+                // tool detection issues should always be shown as warnings
+                cargo_output,
+            )
+            .ok()
+            .and_then(|o| String::from_utf8(o).ok())
+            {
+                Some(s) => s,
+                None => {
+                    // --version failed. fallback to gnu
+                    cargo_output.print_warning(&format_args!("Failed to run: {:?}", cmd));
+                    return ToolFamily::Gnu;
+                }
+            };
+            if stdout.contains("clang") {
+                ToolFamily::Clang
+            } else if stdout.contains("GCC") {
+                ToolFamily::Gnu
+            } else {
+                // --version doesn't include clang for GCC
+                cargo_output.print_warning(&format_args!(
+                    "Compiler version doesn't include clang or GCC: {:?}",
+                    cmd
+                ));
+                ToolFamily::Gnu
+            }
+        }
+        let detect_family = |path: &Path| -> ToolFamily {
+            if let Some(family) = cached_compiler_family.lock().unwrap().get(path) {
+                return *family;
+            }
+
+            let family = detect_family_inner(path, cargo_output);
+            cached_compiler_family
+                .lock()
+                .unwrap()
+                .insert(path.into(), family);
+            family
+        };
+
+        // Try to detect family of the tool from its name, falling back to Gnu.
+        let family = if let Some(fname) = path.file_name().and_then(|p| p.to_str()) {
+            if fname.contains("clang-cl") {
+                ToolFamily::Msvc { clang_cl: true }
+            } else if fname.ends_with("cl") || fname == "cl.exe" {
+                ToolFamily::Msvc { clang_cl: false }
+            } else if fname.contains("clang") {
+                match clang_driver {
+                    Some("cl") => ToolFamily::Msvc { clang_cl: true },
+                    _ => ToolFamily::Clang,
+                }
+            } else {
+                detect_family(&path)
+            }
+        } else {
+            detect_family(&path)
+        };
+
+        Tool {
+            path,
+            cc_wrapper_path: None,
+            cc_wrapper_args: Vec::new(),
+            args: Vec::new(),
+            env: Vec::new(),
+            family,
+            cuda,
+            removed_args: Vec::new(),
+            has_internal_target_arg: false,
+        }
+    }
+
+    /// Add an argument to be stripped from the final command arguments.
+    pub(crate) fn remove_arg(&mut self, flag: OsString) {
+        self.removed_args.push(flag);
+    }
+
+    /// Push an "exotic" flag to the end of the compiler's arguments list.
+    ///
+    /// Nvidia compiler accepts only the most common compiler flags like `-D`,
+    /// `-I`, `-c`, etc. Options meant specifically for the underlying
+    /// host C++ compiler have to be prefixed with `-Xcompiler`.
+    /// [Another possible future application for this function is passing
+    /// clang-specific flags to clang-cl, which otherwise accepts only
+    /// MSVC-specific options.]
+    pub(crate) fn push_cc_arg(&mut self, flag: OsString) {
+        if self.cuda {
+            self.args.push("-Xcompiler".into());
+        }
+        self.args.push(flag);
+    }
+
+    /// Checks if an argument or flag has already been specified or conflicts.
+    ///
+    /// Currently only checks optimization flags.
+    pub(crate) fn is_duplicate_opt_arg(&self, flag: &OsString) -> bool {
+        let flag = flag.to_str().unwrap();
+        let mut chars = flag.chars();
+
+        // Only duplicate check compiler flags
+        if self.is_like_msvc() {
+            if chars.next() != Some('/') {
+                return false;
+            }
+        } else if self.is_like_gnu() || self.is_like_clang() {
+            if chars.next() != Some('-') {
+                return false;
+            }
+        }
+
+        // Check for existing optimization flags (-O, /O)
+        if chars.next() == Some('O') {
+            return self
+                .args()
+                .iter()
+                .any(|a| a.to_str().unwrap_or("").chars().nth(1) == Some('O'));
+        }
+
+        // TODO Check for existing -m..., -m...=..., /arch:... flags
+        false
+    }
+
+    /// Don't push optimization arg if it conflicts with existing args.
+    pub(crate) fn push_opt_unless_duplicate(&mut self, flag: OsString) {
+        if self.is_duplicate_opt_arg(&flag) {
+            println!("Info: Ignoring duplicate arg {:?}", &flag);
+        } else {
+            self.push_cc_arg(flag);
+        }
+    }
+
+    /// Converts this compiler into a `Command` that's ready to be run.
+    ///
+    /// This is useful for when the compiler needs to be executed and the
+    /// command returned will already have the initial arguments and environment
+    /// variables configured.
+    pub fn to_command(&self) -> Command {
+        let mut cmd = match self.cc_wrapper_path {
+            Some(ref cc_wrapper_path) => {
+                let mut cmd = Command::new(cc_wrapper_path);
+                cmd.arg(&self.path);
+                cmd
+            }
+            None => Command::new(&self.path),
+        };
+        cmd.args(&self.cc_wrapper_args);
+
+        let value = self
+            .args
+            .iter()
+            .filter(|a| !self.removed_args.contains(a))
+            .collect::<Vec<_>>();
+        cmd.args(&value);
+
+        for (k, v) in self.env.iter() {
+            cmd.env(k, v);
+        }
+        cmd
+    }
+
+    /// Returns the path for this compiler.
+    ///
+    /// Note that this may not be a path to a file on the filesystem, e.g. "cc",
+    /// but rather something which will be resolved when a process is spawned.
+    pub fn path(&self) -> &Path {
+        &self.path
+    }
+
+    /// Returns the default set of arguments to the compiler needed to produce
+    /// executables for the target this compiler generates.
+    pub fn args(&self) -> &[OsString] {
+        &self.args
+    }
+
+    /// Returns the set of environment variables needed for this compiler to
+    /// operate.
+    ///
+    /// This is typically only used for MSVC compilers currently.
+    pub fn env(&self) -> &[(OsString, OsString)] {
+        &self.env
+    }
+
+    /// Returns the compiler command in format of CC environment variable.
+    /// Or empty string if CC env was not present
+    ///
+    /// This is typically used by configure script
+    pub fn cc_env(&self) -> OsString {
+        match self.cc_wrapper_path {
+            Some(ref cc_wrapper_path) => {
+                let mut cc_env = cc_wrapper_path.as_os_str().to_owned();
+                cc_env.push(" ");
+                cc_env.push(self.path.to_path_buf().into_os_string());
+                for arg in self.cc_wrapper_args.iter() {
+                    cc_env.push(" ");
+                    cc_env.push(arg);
+                }
+                cc_env
+            }
+            None => OsString::from(""),
+        }
+    }
+
+    /// Returns the compiler flags in format of CFLAGS environment variable.
+    /// Important here - this will not be CFLAGS from env, its internal gcc's flags to use as CFLAGS
+    /// This is typically used by configure script
+    pub fn cflags_env(&self) -> OsString {
+        let mut flags = OsString::new();
+        for (i, arg) in self.args.iter().enumerate() {
+            if i > 0 {
+                flags.push(" ");
+            }
+            flags.push(arg);
+        }
+        flags
+    }
+
+    /// Whether the tool is GNU Compiler Collection-like.
+    pub fn is_like_gnu(&self) -> bool {
+        self.family == ToolFamily::Gnu
+    }
+
+    /// Whether the tool is Clang-like.
+    pub fn is_like_clang(&self) -> bool {
+        self.family == ToolFamily::Clang
+    }
+
+    /// Whether the tool is AppleClang under .xctoolchain
+    #[cfg(target_vendor = "apple")]
+    pub(crate) fn is_xctoolchain_clang(&self) -> bool {
+        let path = self.path.to_string_lossy();
+        path.contains(".xctoolchain/")
+    }
+    #[cfg(not(target_vendor = "apple"))]
+    pub(crate) fn is_xctoolchain_clang(&self) -> bool {
+        false
+    }
+
+    /// Whether the tool is MSVC-like.
+    pub fn is_like_msvc(&self) -> bool {
+        match self.family {
+            ToolFamily::Msvc { .. } => true,
+            _ => false,
+        }
+    }
+}
+
+/// Represents the family of tools this tool belongs to.
+///
+/// Each family of tools differs in how and what arguments they accept.
+///
+/// Detection of a family is done on best-effort basis and may not accurately reflect the tool.
+#[derive(Copy, Clone, Debug, PartialEq)]
+pub enum ToolFamily {
+    /// Tool is GNU Compiler Collection-like.
+    Gnu,
+    /// Tool is Clang-like. It differs from the GCC in a sense that it accepts superset of flags
+    /// and its cross-compilation approach is different.
+    Clang,
+    /// Tool is the MSVC cl.exe.
+    Msvc { clang_cl: bool },
+}
+
+impl ToolFamily {
+    /// What the flag to request debug info for this family of tools look like
+    pub(crate) fn add_debug_flags(&self, cmd: &mut Tool, dwarf_version: Option<u32>) {
+        match *self {
+            ToolFamily::Msvc { .. } => {
+                cmd.push_cc_arg("-Z7".into());
+            }
+            ToolFamily::Gnu | ToolFamily::Clang => {
+                cmd.push_cc_arg(
+                    dwarf_version
+                        .map_or_else(|| "-g".into(), |v| format!("-gdwarf-{}", v))
+                        .into(),
+                );
+            }
+        }
+    }
+
+    /// What the flag to force frame pointers.
+    pub(crate) fn add_force_frame_pointer(&self, cmd: &mut Tool) {
+        match *self {
+            ToolFamily::Gnu | ToolFamily::Clang => {
+                cmd.push_cc_arg("-fno-omit-frame-pointer".into());
+            }
+            _ => (),
+        }
+    }
+
+    /// What the flags to enable all warnings
+    pub(crate) fn warnings_flags(&self) -> &'static str {
+        match *self {
+            ToolFamily::Msvc { .. } => "-W4",
+            ToolFamily::Gnu | ToolFamily::Clang => "-Wall",
+        }
+    }
+
+    /// What the flags to enable extra warnings
+    pub(crate) fn extra_warnings_flags(&self) -> Option<&'static str> {
+        match *self {
+            ToolFamily::Msvc { .. } => None,
+            ToolFamily::Gnu | ToolFamily::Clang => Some("-Wextra"),
+        }
+    }
+
+    /// What the flag to turn warning into errors
+    pub(crate) fn warnings_to_errors_flag(&self) -> &'static str {
+        match *self {
+            ToolFamily::Msvc { .. } => "-WX",
+            ToolFamily::Gnu | ToolFamily::Clang => "-Werror",
+        }
+    }
+
+    pub(crate) fn verbose_stderr(&self) -> bool {
+        *self == ToolFamily::Clang
+    }
+}