Use the right methods on Android

src/libstd/sys/unix/android.rs

@@ -18,10 +18,7 @@
 
 #![cfg(target_os = "android")]
 
-use libc::{c_int, sighandler_t, ssize_t};
-
-use super::{cvt, cvt_r};
-use crate::io;
+use libc::{c_int, sighandler_t};
 
 // The `log2` and `log2f` functions apparently appeared in android-18, or at
 // least you can see they're not present in the android-17 header [1] and they

src/libstd/sys/unix/fd.rs

@@ -81,9 +81,9 @@ impl FileDesc {
             count: usize,
             offset: i64,
         ) -> io::Result<isize> {
-            #[cfg(not(target_os = "linux"))]
+            #[cfg(not(any(target_os = "linux", target_os = "android")))]
             use libc::pread as pread64;
-            #[cfg(target_os = "linux")]
+            #[cfg(any(target_os = "linux", target_os = "android"))]
             use libc::pread64;
             cvt(pread64(fd, buf, count, offset))
         }
@@ -129,9 +129,9 @@ impl FileDesc {
             count: usize,
             offset: i64,
         ) -> io::Result<isize> {
-            #[cfg(not(target_os = "linux"))]
+            #[cfg(not(any(target_os = "linux", target_os = "android")))]
             use libc::pwrite as pwrite64;
-            #[cfg(target_os = "linux")]
+            #[cfg(any(target_os = "linux", target_os = "android"))]
             use libc::pwrite64;
             cvt(pwrite64(fd, buf, count, offset))
         }

src/libstd/sys/unix/fs.rs

@@ -30,8 +30,8 @@ use libc::fstatat64;
 use libc::readdir_r as readdir64_r;
 #[cfg(target_os = "android")]
 use libc::{
-    dirent as dirent64, fstat as fstat64, fstatat as fstatat64, lseek64, lstat as lstat64,
-    open as open64, stat as stat64,
+    dirent as dirent64, fstat as fstat64, fstatat as fstatat64, ftruncate64, lseek64,
+    lstat as lstat64, off64_t, open as open64, stat as stat64,
 };
 #[cfg(not(any(
     target_os = "linux",