[PATCH 02/10] remote: Eliminate remote_hostio_close_cleanup

Pedro Alves
2018-05-16T14:18:36Z

gdb/ChangeLog:
yyyy-mm-dd Pedro Alves <palves@redhat.com>

* remote.c (remote_hostio_close_cleanup): Delete.
(class scoped_remote_fd): New.
(remote_file_put, remote_file_get): Use it.
---
gdb/remote.c | 89 ++++++++++++++++++++++++++++++++++++++++--------------------
1 file changed, 60 insertions(+), 29 deletions(-)

diff --git a/gdb/remote.c b/gdb/remote.c
index ca72c1a1c2..bc4815c67e 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -12198,20 +12198,52 @@ remote_hostio_error (int errnum)
error (_("Remote I/O error: %s"), safe_strerror (host_error));
}

-static void
-remote_hostio_close_cleanup (void *opaque)
+/* A RAII wrapper around a remote file descriptor. */
+
+class scoped_remote_fd
{
- int fd = *(int *) opaque;
- int remote_errno;
+public:
+ explicit scoped_remote_fd (int fd)
+ : m_fd (fd)
+ {
+ }

- remote_hostio_close (find_target_at (process_stratum), fd, &remote_errno);
-}
+ ~scoped_remote_fd ()
+ {
+ if (m_fd != -1)
+ {
+ int remote_errno;
+ remote_hostio_close (find_target_at (process_stratum),
+ m_fd, &remote_errno);
+ }
+ }
+
+ DISABLE_COPY_AND_ASSIGN (scoped_remote_fd);
+
+ /* Release ownership of the file descriptor, and return it. */
+ int release () noexcept
+ {
+ int fd = m_fd;
+ m_fd = -1;
+ return fd;
+ }
+
+ /* Return the owned file descriptor. */
+ int get () const noexcept
+ {
+ return m_fd;
+ }
+
+private:
+ /* The owned remote I/O file descriptor. */
+ int m_fd;
+};

void
remote_file_put (const char *local_file, const char *remote_file, int from_tty)
{
- struct cleanup *back_to, *close_cleanup;
- int retcode, fd, remote_errno, bytes, io_size;
+ struct cleanup *back_to;
+ int retcode, remote_errno, bytes, io_size;
gdb_byte *buffer;
int bytes_in_buffer;
int saw_eof;
@@ -12225,11 +12257,12 @@ remote_file_put (const char *local_file, const char *remote_file, int from_tty)
if (file == NULL)
perror_with_name (local_file);

- fd = remote_hostio_open (find_target_at (process_stratum), NULL,
- remote_file, (FILEIO_O_WRONLY | FILEIO_O_CREAT
- | FILEIO_O_TRUNC),
- 0700, 0, &remote_errno);
- if (fd == -1)
+ scoped_remote_fd fd
+ (remote_hostio_open (find_target_at (process_stratum), NULL,
+ remote_file, (FILEIO_O_WRONLY | FILEIO_O_CREAT
+ | FILEIO_O_TRUNC),
+ 0700, 0, &remote_errno));
+ if (fd.get () == -1)
remote_hostio_error (remote_errno);

/* Send up to this many bytes at once. They won't all fit in the
@@ -12238,8 +12271,6 @@ remote_file_put (const char *local_file, const char *remote_file, int from_tty)
buffer = (gdb_byte *) xmalloc (io_size);
back_to = make_cleanup (xfree, buffer);

- close_cleanup = make_cleanup (remote_hostio_close_cleanup, &fd);
-
bytes_in_buffer = 0;
saw_eof = 0;
offset = 0;
@@ -12271,7 +12302,7 @@ remote_file_put (const char *local_file, const char *remote_file, int from_tty)
bytes_in_buffer = 0;

retcode = remote_hostio_pwrite (find_target_at (process_stratum),
- fd, buffer, bytes,
+ fd.get (), buffer, bytes,
offset, &remote_errno);

if (retcode < 0)
@@ -12289,8 +12320,8 @@ remote_file_put (const char *local_file, const char *remote_file, int from_tty)
offset += retcode;
}

- discard_cleanups (close_cleanup);
- if (remote_hostio_close (find_target_at (process_stratum), fd, &remote_errno))
+ if (remote_hostio_close (find_target_at (process_stratum),
+ fd.release (), &remote_errno))
remote_hostio_error (remote_errno);

if (from_tty)
@@ -12301,8 +12332,8 @@ remote_file_put (const char *local_file, const char *remote_file, int from_tty)
void
remote_file_get (const char *remote_file, const char *local_file, int from_tty)
{
- struct cleanup *back_to, *close_cleanup;
- int fd, remote_errno, bytes, io_size;
+ struct cleanup *back_to;
+ int remote_errno, bytes, io_size;
gdb_byte *buffer;
ULONGEST offset;
struct remote_state *rs = get_remote_state ();
@@ -12310,10 +12341,11 @@ remote_file_get (const char *remote_file, const char *local_file, int from_tty)
if (!rs->remote_desc)
error (_("command can only be used with remote target"));

- fd = remote_hostio_open (find_target_at (process_stratum), NULL,
- remote_file, FILEIO_O_RDONLY, 0, 0,
- &remote_errno);
- if (fd == -1)
+ scoped_remote_fd fd
+ (remote_hostio_open (find_target_at (process_stratum), NULL,
+ remote_file, FILEIO_O_RDONLY, 0, 0,
+ &remote_errno));
+ if (fd.get () == -1)
remote_hostio_error (remote_errno);

gdb_file_up file = gdb_fopen_cloexec (local_file, "wb");
@@ -12326,13 +12358,12 @@ remote_file_get (const char *remote_file, const char *local_file, int from_tty)
buffer = (gdb_byte *) xmalloc (io_size);
back_to = make_cleanup (xfree, buffer);

- close_cleanup = make_cleanup (remote_hostio_close_cleanup, &fd);
-
offset = 0;
while (1)
{
bytes = remote_hostio_pread (find_target_at (process_stratum),
- fd, buffer, io_size, offset, &remote_errno);
+ fd.get (), buffer, io_size, offset,
+ &remote_errno);
if (bytes == 0)
/* Success, but no bytes, means end-of-file. */
break;
@@ -12346,8 +12377,8 @@ remote_file_get (const char *remote_file, const char *local_file, int from_tty)
perror_with_name (local_file);
}

- discard_cleanups (close_cleanup);
- if (remote_hostio_close (find_target_at (process_stratum), fd, &remote_errno))
+ if (remote_hostio_close (find_target_at (process_stratum),
+ fd.release (), &remote_errno))
remote_hostio_error (remote_errno);

if (from_tty)
--
2.14.3