Working mmap.

* Also replaced syscall! with in-tree version that calls syscall_return() on result. * Learned how to use and read strace and objdump today too.
anp · May 10, 2016 · 0e93e5fb122101f8fb7da2bed40ef1b37727293e · 0e93e5f
1 parent 75b0329
commit 0e93e5fb122101f8fb7da2bed40ef1b37727293e
Unified Split

Showing with 117 additions and 45 deletions.

+1 −0 .gitignore

+3 −0 Cargo.toml

+0 −38 musl/src/mman/mmap.c

+3 −2 src/lib.rs

+52 −2 src/mmap.rs

+1 −0 src/platform/linux-x86_64/c_types.rs

+7 −1 src/platform/linux-x86_64/mman.rs

+50 −2 src/syscall_mgt.rs
diff --git a/.gitignore b/.gitignore
@@ -4,5 +4,6 @@ Cargo.lock
 build
 *.a
 *.o
+*.lo
 libc-test/src/common/options.h
 rusl_failures
diff --git a/Cargo.toml b/Cargo.toml
@@ -11,3 +11,6 @@ crate-type = ["staticlib", "dylib"]
 lazy_static = { version = "0.2.1", features = ["spin_no_std"] }
 rlibc = "1.0.0"
 syscall = "0.2.1"
+
+[profile.release]
+debug = true
diff --git a/musl/src/mman/mmap.c b/musl/src/mman/mmap.c
diff --git a/src/lib.rs b/src/lib.rs
@@ -5,13 +5,14 @@

 #[macro_use]
 extern crate lazy_static;
-#[macro_use]
 extern crate syscall;

+#[macro_use]
+pub mod syscall_mgt;
+
 pub mod malloc;
 pub mod mmap;
 pub mod string;
-pub mod syscall_mgt;
 pub mod thread;
 pub mod time;
 pub mod unistd;
diff --git a/src/mmap.rs b/src/mmap.rs
@@ -1,7 +1,57 @@
-use core::mem::size_of;
-use core::usize;
+use core::isize;

 use c_types::*;
+use errno::{set_errno, EINVAL, ENOMEM};
+use platform::mman::*;
+use thread::vmlock::__vm_wait;
+
+#[no_mangle]
+pub unsafe extern "C" fn __mmap(start: *mut c_void,
+                                len: size_t,
+                                prot: c_int,
+                                flags: c_int,
+                                fd: c_int,
+                                off: off_t)
+                                -> *mut c_void {
+
+    if (off & (PAGE_SIZE - 1)) != 0 {
+        set_errno(EINVAL);
+        return MAP_FAILED;
+    }
+
+    if len >= isize::MAX as usize {
+        set_errno(ENOMEM);
+        return MAP_FAILED;
+    }
+
+    if flags & MAP_FIXED != 0 {
+        __vm_wait();
+    }
+
+    syscall!(MMAP, start, len, prot, flags, fd, off) as *mut c_void
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn mmap(start: *mut c_void,
+                              len: size_t,
+                              prot: c_int,
+                              flags: c_int,
+                              fd: c_int,
+                              off: off_t)
+                              -> *mut c_void {
+    __mmap(start, len, prot, flags, fd, off)
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn mmap64(start: *mut c_void,
+                                len: size_t,
+                                prot: c_int,
+                                flags: c_int,
+                                fd: c_int,
+                                off: off_t)
+                                -> *mut c_void {
+    __mmap(start, len, prot, flags, fd, off)
+}

 #[no_mangle]
 pub unsafe extern "C" fn madvise(address: *mut c_void, len: usize, advice: c_int) -> c_int {
diff --git a/src/platform/linux-x86_64/c_types.rs b/src/platform/linux-x86_64/c_types.rs
@@ -41,6 +41,7 @@ pub type ptrdiff_t = isize;
 pub type intptr_t = isize;
 pub type uintptr_t = usize;
 pub type ssize_t = isize;
+pub type off_t = i64;

 pub type pid_t = i32;
 pub type uid_t = u32;
diff --git a/src/platform/linux-x86_64/mman.rs b/src/platform/linux-x86_64/mman.rs
@@ -1 +1,7 @@
-pub const MAP_FAILED: usize = (!1i64) as usize;
+use c_types::*;
+
+pub const PAGE_SIZE: off_t = 4096;
+
+pub const MAP_FAILED: *mut c_void = 0xffffffffffffffff as *mut c_void;
+
+pub const MAP_FIXED: c_int = 0x10;
diff --git a/src/syscall_mgt.rs b/src/syscall_mgt.rs
@@ -4,12 +4,60 @@ use c_types::*;
 use errno::set_errno;

 // from musl/src/internal/syscall_ret.c
-pub unsafe fn syscall_return(code: usize) -> isize {
+pub unsafe fn syscall_return(code: usize) -> usize {
    let max_err: usize = transmute(-4096i64);
    if code > max_err {
        set_errno(-(code as c_int));
-        -1
+        (-1isize) as usize
    } else {
        transmute(code)
    }
 }
+
+// from the syscall.rs crate, just added the return handling
+#[macro_export]
+macro_rules! syscall {
+    ($nr:ident)
+        => ( ::syscall_mgt::syscall_return(::syscall::syscall0(
+                ::syscall::nr::$nr)) );
+
+    ($nr:ident, $a1:expr)
+        => ( ::syscall_mgt::syscall_return(::syscall::syscall1(
+                ::syscall::nr::$nr,
+                $a1 as usize)) );
+
+    ($nr:ident, $a1:expr, $a2:expr)
+        => ( ::syscall_mgt::syscall_return(::syscall::syscall2(
+                ::syscall::nr::$nr,
+                $a1 as usize, $a2 as usize)) );
+
+    ($nr:ident, $a1:expr, $a2:expr, $a3:expr)
+        => ( ::syscall_mgt::syscall_return(::syscall::syscall3(
+                ::syscall::nr::$nr,
+                $a1 as usize, $a2 as usize, $a3 as usize)) );
+
+    ($nr:ident, $a1:expr, $a2:expr, $a3:expr, $a4:expr)
+        => ( ::syscall_mgt::syscall_return(::syscall::syscall4(
+                ::syscall::nr::$nr,
+                $a1 as usize, $a2 as usize, $a3 as usize,
+                $a4 as usize)) );
+
+    ($nr:ident, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr)
+        => ( ::syscall_mgt::syscall_return(::syscall::syscall5(
+                ::syscall::nr::$nr,
+                $a1 as usize, $a2 as usize, $a3 as usize,
+                $a4 as usize, $a5 as usize)) );
+
+    ($nr:ident, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr, $a6:expr)
+        => ( ::syscall_mgt::syscall_return(::syscall::syscall6(
+                ::syscall::nr::$nr,
+                $a1 as usize, $a2 as usize, $a3 as usize,
+                $a4 as usize, $a5 as usize, $a6 as usize)) );
+
+    ($nr:ident, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr, $a6:expr, $a7:expr)
+        => ( ::syscall_mgt::syscall_return(::syscall::syscall7(
+                ::syscall::nr::$nr,
+                $a1 as usize, $a2 as usize, $a3 as usize,
+                $a4 as usize, $a5 as usize, $a6 as usize,
+                $a7 as usize)) );
+}