ChangeLog:

	* configure.ac [AC_CHECK_FUNCS]: Check for readlink.
	* config.in, configure: Regenerate.

	* target.h (struct target_ops): Add to_fileio_readlink.
	(target_fileio_readlink): Add prototype.
	* target.c (target_fileio_readlink): New function.

	* inf-child.c: Conditionally include <sys/param.h>.
	(inf_child_fileio_readlink): New function.
	(inf_child_target): Install it.

	* remote.c (PACKET_vFile_readlink): New enum value.
	(remote_hostio_readlink): New function.
	(init_remote_ops): Install it.
	(_initialize_remote): Handle vFile:readlink packet type.

doc/ChangeLog:

	* gdb.texinfo (Remote Configuration): Document
	"set remote hostio-readlink-packet" command.
	(General Query Packets): Document vFile:readlink packet.

gdbserver/ChangeLog:

	* hostio.c (handle_readlink): New function.
	(handle_vFile): Call it to handle "vFile:readlink" packets.

1 files changed, 34 insertions, 0 deletions

diff --git a/gdb/inf-child.c b/gdb/inf-child.c
index 0dda331..2271824 100644
--- a/gdb/inf-child.c
+++ b/gdb/inf-child.c
@@ -29,6 +29,9 @@
 #include "inf-child.h"
 #include "gdb/fileio.h"
 
+#ifdef HAVE_SYS_PARAM_H
+#include <sys/param.h>		/* for MAXPATHLEN */
+#endif
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
@@ -299,6 +302,36 @@ inf_child_fileio_unlink (const char *filename, int *target_errno)
   return ret;
 }
 
+/* Read value of symbolic link FILENAME on the target.  Return a
+   null-terminated string allocated via xmalloc, or NULL if an error
+   occurs (and set *TARGET_ERRNO).  */
+static char *
+inf_child_fileio_readlink (const char *filename, int *target_errno)
+{
+  /* We support readlink only on systems that also provide a compile-time
+     maximum path length (MAXPATHLEN), at least for now.  */
+#if defined (HAVE_READLINK) && defined (MAXPATHLEN)
+  char buf[MAXPATHLEN];
+  int len;
+  char *ret;
+
+  len = readlink (filename, buf, sizeof buf);
+  if (len < 0)
+    {
+      *target_errno = inf_child_errno_to_fileio_error (errno);
+      return NULL;
+    }
+
+  ret = xmalloc (len + 1);
+  memcpy (ret, buf, len);
+  ret[len] = '\0';
+  return ret;
+#else
+  *target_errno = FILEIO_ENOSYS;
+  return NULL;
+#endif
+}
+
 
 struct target_ops *
 inf_child_target (void)
@@ -336,6 +369,7 @@ inf_child_target (void)
   t->to_fileio_pread = inf_child_fileio_pread;
   t->to_fileio_close = inf_child_fileio_close;
   t->to_fileio_unlink = inf_child_fileio_unlink;
+  t->to_fileio_readlink = inf_child_fileio_readlink;
   t->to_magic = OPS_MAGIC;
   return t;
 }