1 files changed, 105 insertions, 0 deletions
diff --git a/compiler/rustc_codegen_llvm/src/llvm/archive_ro.rs b/compiler/rustc_codegen_llvm/src/llvm/archive_ro.rs
new file mode 100644
index 000000000..64db4f746
--- /dev/null
+++ b/compiler/rustc_codegen_llvm/src/llvm/archive_ro.rs
@@ -0,0 +1,105 @@
+//! A wrapper around LLVM's archive (.a) code
+
+use rustc_fs_util::path_to_c_string;
+use std::path::Path;
+use std::slice;
+use std::str;
+
+pub struct ArchiveRO {
+    pub raw: &'static mut super::Archive,
+}
+
+unsafe impl Send for ArchiveRO {}
+
+pub struct Iter<'a> {
+    raw: &'a mut super::ArchiveIterator<'a>,
+}
+
+pub struct Child<'a> {
+    pub raw: &'a mut super::ArchiveChild<'a>,
+}
+
+impl ArchiveRO {
+    /// Opens a static archive for read-only purposes. This is more optimized
+    /// than the `open` method because it uses LLVM's internal `Archive` class
+    /// rather than shelling out to `ar` for everything.
+    ///
+    /// If this archive is used with a mutable method, then an error will be
+    /// raised.
+    pub fn open(dst: &Path) -> Result<ArchiveRO, String> {
+        unsafe {
+            let s = path_to_c_string(dst);
+            let ar = super::LLVMRustOpenArchive(s.as_ptr()).ok_or_else(|| {
+                super::last_error().unwrap_or_else(|| "failed to open archive".to_owned())
+            })?;
+            Ok(ArchiveRO { raw: ar })
+        }
+    }
+
+    pub fn iter(&self) -> Iter<'_> {
+        unsafe { Iter { raw: super::LLVMRustArchiveIteratorNew(self.raw) } }
+    }
+}
+
+impl Drop for ArchiveRO {
+    fn drop(&mut self) {
+        unsafe {
+            super::LLVMRustDestroyArchive(&mut *(self.raw as *mut _));
+        }
+    }
+}
+
+impl<'a> Iterator for Iter<'a> {
+    type Item = Result<Child<'a>, String>;
+
+    fn next(&mut self) -> Option<Result<Child<'a>, String>> {
+        unsafe {
+            match super::LLVMRustArchiveIteratorNext(self.raw) {
+                Some(raw) => Some(Ok(Child { raw })),
+                None => super::last_error().map(Err),
+            }
+        }
+    }
+}
+
+impl<'a> Drop for Iter<'a> {
+    fn drop(&mut self) {
+        unsafe {
+            super::LLVMRustArchiveIteratorFree(&mut *(self.raw as *mut _));
+        }
+    }
+}
+
+impl<'a> Child<'a> {
+    pub fn name(&self) -> Option<&'a str> {
+        unsafe {
+            let mut name_len = 0;
+            let name_ptr = super::LLVMRustArchiveChildName(self.raw, &mut name_len);
+            if name_ptr.is_null() {
+                None
+            } else {
+                let name = slice::from_raw_parts(name_ptr as *const u8, name_len as usize);
+                str::from_utf8(name).ok().map(|s| s.trim())
+            }
+        }
+    }
+
+    pub fn data(&self) -> &'a [u8] {
+        unsafe {
+            let mut data_len = 0;
+            let data_ptr = super::LLVMRustArchiveChildData(self.raw, &mut data_len);
+            if data_ptr.is_null() {
+                panic!("failed to read data from archive child");
+            }
+            slice::from_raw_parts(data_ptr as *const u8, data_len as usize)
+        }
+    }
+}
+
+impl<'a> Drop for Child<'a> {
+    fn drop(&mut self) {
+        unsafe {
+            super::LLVMRustArchiveChildFree(&mut *(self.raw as *mut _));
+        }
+    }
+}