rustpkg: Pass command-line arguments to rustc

rustpkg now accepts most of rustc's command-line arguments and passes
them along to rustc when building or installing.

A few rarely-used arguments aren't implemented yet.

rustpkg doesn't support flags that don't make sense with rustpkg
(for example, --bin and --lib, which get inferred from crate file names).

Closes #8522

Author: catamorphism

src/librustpkg/api.rs

@@ -29,6 +29,8 @@ pub fn default_context(p: Path) -> BuildContext {
 pub fn new_default_context(c: workcache::Context, p: Path) -> BuildContext {
     BuildContext {
         context: Context {
+            cfgs: ~[],
+            rustc_flags: RustcFlags::default(),
             use_rust_path_hack: false,
             sysroot: p
         },
@@ -44,7 +46,6 @@ fn binary_is_fresh(path: &str, in_hash: &str) -> bool {
     in_hash == digest_only_date(&Path(path))
 }
 
-
 pub fn new_workcache_context(p: &Path) -> workcache::Context {
     let db_file = p.push("rustpkg_db.json"); // ??? probably wrong
     debug!("Workcache database file: %s", db_file.to_str());

src/librustpkg/context.rs

@@ -10,11 +10,16 @@
 
 // Context data structure used by rustpkg
 
-use std::os;
+use std::{io, os};
 use extra::workcache;
+use rustc::driver::session::{OptLevel, No};
 
 #[deriving(Clone)]
 pub struct Context {
+    // Config strings that the user passed in with --cfg
+    cfgs: ~[~str],
+    // Flags to pass to rustc
+    rustc_flags: RustcFlags,
     // If use_rust_path_hack is true, rustpkg searches for sources
     // in *package* directories that are in the RUST_PATH (for example,
     // FOO/src/bar-0.1 instead of FOO). The flag doesn't affect where
@@ -40,15 +45,82 @@ impl BuildContext {
     pub fn sysroot_to_use(&self) -> Path {
         self.context.sysroot_to_use()
     }
+
+    /// Returns the flags to pass to rustc, as a vector of strings
+    pub fn flag_strs(&self) -> ~[~str] {
+        self.context.flag_strs()
+    }
+
+    pub fn compile_upto(&self) -> StopBefore {
+        self.context.compile_upto()
+    }
+}
+
+/*
+Deliberately unsupported rustc flags:
+   --bin, --lib           inferred from crate file names
+   -L                     inferred from extern mods
+   --out-dir              inferred from RUST_PATH
+   --test                 use `rustpkg test`
+   -v -h --ls             don't make sense with rustpkg
+   -W -A -D -F -          use pragmas instead
+
+rustc flags that aren't implemented yet:
+   --passes
+   --llvm-arg
+   --target-feature
+   --android-cross-path
+*/
+pub struct RustcFlags {
+    compile_upto: StopBefore,
+    // Linker to use with the --linker flag
+    linker: Option<~str>,
+    // Extra arguments to pass to rustc with the --link-args flag
+    link_args: Option<~str>,
+    // Optimization level. 0 = default. -O = 2.
+    optimization_level: OptLevel,
+    // True if the user passed in --save-temps
+    save_temps: bool,
+    // Target (defaults to rustc's default target)
+    target: Option<~str>,
+    // Target CPU (defaults to rustc's default target CPU)
+    target_cpu: Option<~str>,
+    // Any -Z features
+    experimental_features: Option<~[~str]>
+}
+
+impl Clone for RustcFlags {
+    fn clone(&self) -> RustcFlags {
+        RustcFlags {
+            compile_upto: self.compile_upto,
+            linker: self.linker.clone(),
+            link_args: self.link_args.clone(),
+            optimization_level: self.optimization_level,
+            save_temps: self.save_temps,
+            target: self.target.clone(),
+            target_cpu: self.target_cpu.clone(),
+            experimental_features: self.experimental_features.clone()
+        }
+    }
+}
+
+#[deriving(Eq)]
+pub enum StopBefore {
+    Nothing,  // compile everything
+    Link,     // --no-link
+    LLVMCompileBitcode, // --emit-llvm without -S
+    LLVMAssemble, // -S --emit-llvm
+    Assemble, // -S without --emit-llvm
+    Trans,    // --no-trans
+    Pretty,   // --pretty
+    Analysis, // --parse-only
 }
 
 impl Context {
     pub fn sysroot(&self) -> Path {
         self.sysroot.clone()
     }
-}
 
-impl Context {
     /// Debugging
     pub fn sysroot_str(&self) -> ~str {
         self.sysroot.to_str()
@@ -63,6 +135,15 @@ impl Context {
             self.sysroot.pop().pop().pop()
         }
     }
+
+    /// Returns the flags to pass to rustc, as a vector of strings
+    pub fn flag_strs(&self) -> ~[~str] {
+        self.rustc_flags.flag_strs()
+    }
+
+    pub fn compile_upto(&self) -> StopBefore {
+        self.rustc_flags.compile_upto
+    }
 }
 
 /// We assume that if ../../rustc exists, then we're running
@@ -72,3 +153,141 @@ pub fn in_target(sysroot: &Path) -> bool {
     debug!("Checking whether %s is in target", sysroot.to_str());
     os::path_is_dir(&sysroot.pop().pop().push("rustc"))
 }
+
+impl RustcFlags {
+    fn flag_strs(&self) -> ~[~str] {
+        let linker_flag = match self.linker {
+            Some(ref l) => ~[~"--linker", l.clone()],
+            None    => ~[]
+        };
+        let link_args_flag = match self.link_args {
+            Some(ref l) => ~[~"--link-args", l.clone()],
+            None        => ~[]
+        };
+        let save_temps_flag = if self.save_temps { ~[~"--save-temps"] } else { ~[] };
+        let target_flag = match self.target {
+            Some(ref l) => ~[~"--target", l.clone()],
+            None        => ~[]
+        };
+        let target_cpu_flag = match self.target_cpu {
+            Some(ref l) => ~[~"--target-cpu", l.clone()],
+            None        => ~[]
+        };
+        let z_flags = match self.experimental_features {
+            Some(ref ls)    => ls.flat_map(|s| ~[~"-Z", s.clone()]),
+            None            => ~[]
+        };
+        linker_flag
+            + link_args_flag
+            + save_temps_flag
+            + target_flag
+            + target_cpu_flag
+            + z_flags + (match self.compile_upto {
+            LLVMCompileBitcode => ~[~"--emit-llvm"],
+            LLVMAssemble => ~[~"--emit-llvm", ~"-S"],
+            Link => ~[~"-c"],
+            Trans => ~[~"--no-trans"],
+            Assemble => ~[~"-S"],
+            // n.b. Doesn't support all flavors of --pretty (yet)
+            Pretty => ~[~"--pretty"],
+            Analysis => ~[~"--parse-only"],
+            Nothing => ~[]
+        })
+    }
+
+    pub fn default() -> RustcFlags {
+        RustcFlags {
+            linker: None,
+            link_args: None,
+            compile_upto: Nothing,
+            optimization_level: No,
+            save_temps: false,
+            target: None,
+            target_cpu: None,
+            experimental_features: None
+        }
+    }
+}
+
+/// Returns true if any of the flags given are incompatible with the cmd
+pub fn flags_ok_for_cmd(flags: &RustcFlags,
+                        cfgs: &[~str],
+                        cmd: &str, user_supplied_opt_level: bool) -> bool {
+    let complain = |s| {
+        io::println(fmt!("The %s option can only be used with the build command:
+                         rustpkg [options..] build %s [package-ID]", s, s));
+    };
+
+    if flags.linker.is_some() && cmd != "build" && cmd != "install" {
+        io::println("The --linker option can only be used with the build or install commands.");
+        return true;
+    }
+    if flags.link_args.is_some() && cmd != "build" && cmd != "install" {
+        io::println("The --link-args option can only be used with the build or install commands.");
+        return true;
+    }
+
+    if !cfgs.is_empty() && cmd != "build" && cmd != "install" {
+        io::println("The --cfg option can only be used with the build or install commands.");
+        return true;
+    }
+
+    if user_supplied_opt_level && cmd != "build" && cmd != "install" {
+        io::println("The -O and --opt-level options can only be used with the build \
+                    or install commands.");
+        return true;
+    }
+
+    if flags.save_temps  && cmd != "build" && cmd != "install" {
+        io::println("The --save-temps option can only be used with the build \
+                    or install commands.");
+        return true;
+    }
+
+    if flags.target.is_some()  && cmd != "build" && cmd != "install" {
+        io::println("The --target option can only be used with the build \
+                    or install commands.");
+        return true;
+    }
+    if flags.target_cpu.is_some()  && cmd != "build" && cmd != "install" {
+        io::println("The --target-cpu option can only be used with the build \
+                    or install commands.");
+        return true;
+    }
+    if flags.experimental_features.is_some() && cmd != "build" && cmd != "install" {
+        io::println("The -Z option can only be used with the build or install commands.");
+        return true;
+    }
+
+    match flags.compile_upto {
+        Link if cmd != "build" => {
+            complain("--no-link");
+            true
+        }
+        Trans if cmd != "build" => {
+            complain("--no-trans");
+            true
+        }
+        Assemble if cmd != "build" => {
+            complain("-S");
+            true
+        }
+        Pretty if cmd != "build" => {
+            complain("--pretty");
+            true
+        }
+        Analysis if cmd != "build" => {
+            complain("--parse-only");
+            true
+        }
+        LLVMCompileBitcode if cmd != "build" => {
+            complain("--emit-llvm");
+            true
+        }
+        LLVMAssemble if cmd != "build" => {
+            complain("--emit-llvm");
+            true
+        }
+        _ => false
+    }
+}