Brings HDFS VFD binary compatibility stubs from 1.10

The implementation of the HDFS VFD included no-op stubs for HDFS
functionality, even when the HDFS VFD was not being built. These
were removed in the develop branch and those changes were merged
to the 1.12 development trunk after 1.12.0 was released. This
would lead to binary compatibility problems if released in HDF5
1.12.1.

This commit restores the no-op stubs.

2 files changed, 79 insertions, 21 deletions

diff --git a/src/H5FDhdfs.c b/src/H5FDhdfs.c
index aa7091b..c3bfd12 100644
--- a/src/H5FDhdfs.c
+++ b/src/H5FDhdfs.c
@@ -20,21 +20,38 @@
  *             File System (HDFS).
  */
 
-#include "H5private.h"   /* Generic Functions        */
-#include "H5Eprivate.h"  /* Error handling           */
-#include "H5FDprivate.h" /* File drivers             */
-#include "H5FDhdfs.h"    /* hdfs file driver         */
-#include "H5FLprivate.h" /* Free Lists               */
-#include "H5Iprivate.h"  /* IDs                      */
-#include "H5MMprivate.h" /* Memory management        */
-
 #ifdef H5_HAVE_LIBHDFS
-
-/* This source code file is part of the H5FD driver module */
+/* This source code file is part of the H5FD driver module
+ * NOTE: If we're just building the binary compatibility stubs,
+ * we're never going to really initialize the package, so we
+ * don't include this.
+ */
 #include "H5FDdrvr_module.h"
+#endif /* H5_HAVE_LIBHDFS */
+
+#include "H5private.h"      /* Generic Functions        */
+#include "H5Eprivate.h"     /* Error handling           */
+#include "H5FDprivate.h"    /* File drivers             */
+#include "H5FDhdfs.h"       /* hdfs file driver         */
+#include "H5FLprivate.h"    /* Free Lists               */
+#include "H5Iprivate.h"     /* IDs                      */
+#include "H5MMprivate.h"    /* Memory management        */
 
-/* HDFS routines */
-#include "hdfs.h"
+#ifdef H5_HAVE_LIBHDFS
+
+/* HDFS routines
+ * Have to turn off -Wstrict-prototypes as this header contains functions
+ * defined as foo() instead of foo(void), which triggers warnings that HDF5
+ * then interprets as errors.
+ * -Wundef isn't interpreted as an error by HDF5, but the header does do
+ *  some bad symbol interpretation that raises a warning that is out of our
+ *  control.
+ */
+H5_GCC_DIAG_OFF("strict-prototypes")
+H5_GCC_DIAG_OFF("undef")
+#include <hdfs.h>
+H5_GCC_DIAG_ON("strict-prototypes")
+H5_GCC_DIAG_ON("undef")
 
 /* toggle function call prints: 1 turns on */
 #define HDFS_DEBUG 0
@@ -361,7 +378,7 @@ H5FD_hdfs_init(void)
     unsigned int bin_i;
 #endif
 
-    FUNC_ENTER_NOAPI(FAIL)
+    FUNC_ENTER_NOAPI(H5I_INVALID_HID)
 
 #if HDFS_DEBUG
     HDfprintf(stdout, "called %s.\n", FUNC);
@@ -598,8 +615,7 @@ done:
  *
  * Return:      SUCCEED/FAIL
  *
- * Programmer:  John Mainzer
- *              9/10/17
+ * Programmer:  Jacob Smith 2018
  *
  *-------------------------------------------------------------------------
  */
@@ -1700,4 +1716,48 @@ H5FD__hdfs_unlock(H5FD_t H5_ATTR_UNUSED *_file)
 
     FUNC_LEAVE_NOAPI(SUCCEED)
 } /* end H5FD__hdfs_unlock() */
+
+#else /* H5_HAVE_LIBHDFS */
+
+/* No-op stubs to avoid binary compatibility problems with previous
+ * HDF5 1.10 versions. Non-functional versions of these API calls were
+ * erroneously included in the library even when the HDFS VFD was not
+ * configured.
+ */
+hid_t
+H5FD_hdfs_init(void)
+{
+    /* This should never be called since the header doesn't invoke it */
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    FUNC_LEAVE_NOAPI(H5I_INVALID_HID)
+}
+
+herr_t
+H5Pget_fapl_hdfs(hid_t fapl_id, H5FD_hdfs_fapl_t *fa_out)
+{
+    herr_t ret_value = FAIL;
+
+    FUNC_ENTER_API_NOINIT
+    H5TRACE2("e", "i*x", fapl_id, fa_out);
+
+    HGOTO_ERROR(H5E_VFL, H5E_UNSUPPORTED, FAIL, "HDFS VFD not included in the HDF5 library")
+
+done:
+    FUNC_LEAVE_API_NOINIT(ret_value)
+}
+
+herr_t
+H5Pset_fapl_hdfs(hid_t fapl_id, H5FD_hdfs_fapl_t *fa)
+{
+    herr_t ret_value = FAIL;
+
+    FUNC_ENTER_API_NOINIT
+    H5TRACE2("e", "i*x", fapl_id, fa);
+
+    HGOTO_ERROR(H5E_VFL, H5E_UNSUPPORTED, FAIL, "HDFS VFD not included in the HDF5 library")
+
+done:
+    FUNC_LEAVE_API_NOINIT(ret_value)
+}
+
 #endif /* H5_HAVE_LIBHDFS */
diff --git a/src/H5FDhdfs.h b/src/H5FDhdfs.h
index 9d14e9a..5fbc54b 100644
--- a/src/H5FDhdfs.h
+++ b/src/H5FDhdfs.h
@@ -28,11 +28,6 @@
 #define H5FD_HDFS (-1)
 #endif /* H5_HAVE_LIBHDFS */
 
-#ifdef H5_HAVE_LIBHDFS
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 /****************************************************************************
  *
  * Structure: H5FD_hdfs_fapl_t
@@ -112,6 +107,10 @@ typedef struct H5FD_hdfs_fapl_t {
     int32_t stream_buffer_size;
 } H5FD_hdfs_fapl_t;
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 H5_DLL hid_t  H5FD_hdfs_init(void);
 H5_DLL herr_t H5Pget_fapl_hdfs(hid_t fapl_id, H5FD_hdfs_fapl_t *fa_out);
 H5_DLL herr_t H5Pset_fapl_hdfs(hid_t fapl_id, H5FD_hdfs_fapl_t *fa);
@@ -119,6 +118,5 @@ H5_DLL herr_t H5Pset_fapl_hdfs(hid_t fapl_id, H5FD_hdfs_fapl_t *fa);
 #ifdef __cplusplus
 }
 #endif
-#endif /* H5_HAVE_LIBHDFS */
 
 #endif /* ifndef H5FDhdfs_H */