Add fstat support for pipe

src/libos/src/fs/pipe.rs

@@ -44,6 +44,25 @@ impl File for PipeReader {
         self.consumer.pop_slices(bufs)
     }
 
+    fn metadata(&self) -> Result<Metadata> {
+        Ok(Metadata {
+            dev: 0,
+            inode: 0,
+            size: 0,
+            blk_size: 0,
+            blocks: 0,
+            atime: Timespec { sec: 0, nsec: 0 },
+            mtime: Timespec { sec: 0, nsec: 0 },
+            ctime: Timespec { sec: 0, nsec: 0 },
+            type_: FileType::NamedPipe,
+            mode: 0o600,
+            nlinks: 1,
+            uid: 0,
+            gid: 0,
+            rdev: 0,
+        })
+    }
+
     fn access_mode(&self) -> Result<AccessMode> {
         Ok(AccessMode::O_RDONLY)
     }
@@ -111,6 +130,25 @@ impl File for PipeWriter {
         return_errno!(ESPIPE, "Pipe does not support seek")
     }
 
+    fn metadata(&self) -> Result<Metadata> {
+        Ok(Metadata {
+            dev: 0,
+            inode: 0,
+            size: 0,
+            blk_size: 0,
+            blocks: 0,
+            atime: Timespec { sec: 0, nsec: 0 },
+            mtime: Timespec { sec: 0, nsec: 0 },
+            ctime: Timespec { sec: 0, nsec: 0 },
+            type_: FileType::NamedPipe,
+            mode: 0o600,
+            nlinks: 1,
+            uid: 0,
+            gid: 0,
+            rdev: 0,
+        })
+    }
+
     fn access_mode(&self) -> Result<AccessMode> {
         Ok(AccessMode::O_WRONLY)
     }

test/pipe/main.c

@@ -5,6 +5,7 @@
 #include <sys/syscall.h>
 #include <sys/wait.h>
 #include <sys/time.h>
+#include <sys/stat.h>
 #include <fcntl.h>
 #include <poll.h>
 #include <unistd.h>
@@ -26,6 +27,23 @@ static void free_pipe(int *pipe) {
 // ============================================================================
 // Test cases
 // ============================================================================
+int test_fstat() {
+    int pipe_fds[2];
+    struct stat stat_bufs[2];
+    if (pipe(pipe_fds) < 0) {
+        THROW_ERROR("failed to create a pipe");
+    }
+    if (fstat(pipe_fds[0], &stat_bufs[0]) < 0 || fstat(pipe_fds[1], &stat_bufs[1]) < 0) {
+        free_pipe(pipe_fds);
+        THROW_ERROR("failed to fstat pipe fd");
+    }
+    free_pipe(pipe_fds);
+    if (!S_ISFIFO(stat_bufs[0].st_mode) || !S_ISFIFO(stat_bufs[1].st_mode)) {
+        THROW_ERROR("failed to check the pipe st_mode");
+    }
+    return 0;
+}
+
 int test_fcntl_get_flags() {
     int pipe_fds[2];
     if (pipe(pipe_fds) < 0) {
@@ -315,6 +333,7 @@ int test_select_read_write() {
 // Test suite
 // ============================================================================
 static test_case_t test_cases[] = {
+    TEST_CASE(test_fstat),
     TEST_CASE(test_fcntl_get_flags),
     TEST_CASE(test_fcntl_set_flags),
     TEST_CASE(test_create_with_flags),