[RFA/commit] gdbserver: return ENOSYS if readlink not supported.

Joel Brobecker
2012-02-09T16:32:08Z

Hi Pedro,

Given that this problem has been lingering for 3 weeks, I've decided
to just KISS. This reproduces on the GDBserver side what GDB does
when readlink is not supported. Does this look good to you?

Thanks!

gdb/ChangeLog:

* configure.ac: Add readlink to AC_CHECK_FUNCS list.
* configure, config.in: Regenerate.
* hostio.c: Provide an alternate implementation if HAVE_READLINK
is not defined.

Tested on x86_64-linux and x86-windows (by simply rebuilding and verifying
that the correct section of the #if/#else is taken). I'd like to commit
sometime today if possible - people keep reporting this problem.

---
gdb/gdbserver/config.in | 3 +++
gdb/gdbserver/configure | 2 +-
gdb/gdbserver/configure.ac | 2 +-
gdb/gdbserver/hostio.c | 4 ++++
4 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/gdb/gdbserver/config.in b/gdb/gdbserver/config.in
index a9472ea..7fa3b5b 100644
--- a/gdb/gdbserver/config.in
+++ b/gdb/gdbserver/config.in
@@ -128,6 +128,9 @@
/* Define to 1 if you have the `pwrite' function. */
#undef HAVE_PWRITE

+/* Define to 1 if you have the `readlink' function. */
+#undef HAVE_READLINK
+
/* Define to 1 if you have the <sgtty.h> header file. */
#undef HAVE_SGTTY_H

diff --git a/gdb/gdbserver/configure b/gdb/gdbserver/configure
index d92a00f..e251844 100755
--- a/gdb/gdbserver/configure
+++ b/gdb/gdbserver/configure
@@ -4163,7 +4163,7 @@ fi

done

-for ac_func in pread pwrite pread64
+for ac_func in pread pwrite pread64 readlink
do :
as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
diff --git a/gdb/gdbserver/configure.ac b/gdb/gdbserver/configure.ac
index 30666ec..7c86cd4 100644
--- a/gdb/gdbserver/configure.ac
+++ b/gdb/gdbserver/configure.ac
@@ -43,7 +43,7 @@ AC_CHECK_HEADERS(sgtty.h termio.h termios.h sys/reg.h string.h dnl
errno.h fcntl.h signal.h sys/file.h malloc.h dnl
sys/ioctl.h netinet/in.h sys/socket.h netdb.h dnl
netinet/tcp.h arpa/inet.h sys/wait.h)
-AC_CHECK_FUNCS(pread pwrite pread64)
+AC_CHECK_FUNCS(pread pwrite pread64 readlink)
AC_REPLACE_FUNCS(memmem vasprintf vsnprintf)

# Check for UST
diff --git a/gdb/gdbserver/hostio.c b/gdb/gdbserver/hostio.c
index 34e4fa8..03aab58 100644
--- a/gdb/gdbserver/hostio.c
+++ b/gdb/gdbserver/hostio.c
@@ -459,6 +459,7 @@ handle_unlink (char *own_buf)
static void
handle_readlink (char *own_buf, int *new_packet_len)
{
+#if defined (HAVE_READLINK)
char filename[PATH_MAX], linkname[PATH_MAX];
char *p;
int ret, bytes_sent;
@@ -485,6 +486,9 @@ handle_readlink (char *own_buf, int *new_packet_len)
to return a partial response, but simply fail. */
if (bytes_sent < ret)
sprintf (own_buf, "F-1,%x", FILEIO_ENAMETOOLONG);
+#else /* ! HAVE_READLINK */
+ sprintf (own_buf, "F-1,%x", FILEIO_ENOSYS);
+#endif
}

/* Handle all the 'F' file transfer packets. */
--
1.7.1