Disable error reporting during VALID_EC_TYPES eval

... this should not be required after upstream
liberasurecode has more configurable logging

3 files changed, 70 insertions, 23 deletions

diff --git a/pyeclib/core.py b/pyeclib/core.py
index e233915..a0174e1 100644
--- a/pyeclib/core.py
+++ b/pyeclib/core.py
@@ -35,7 +35,8 @@ pyver = float('%s.%s' % sys.version_info[:2])
 class ECPyECLibDriver(object):
 
     def __init__(self, k, m, hd, ec_type,
-                 chksum_type=PyECLib_FRAGHDRCHKSUM_Types.none):
+                 chksum_type=PyECLib_FRAGHDRCHKSUM_Types.none,
+                 validate=False):
         self.k = k
         self.m = m
         self.hd = hd
@@ -56,7 +57,8 @@ class ECPyECLibDriver(object):
             ec_type.value,
             self.hd,
             self.inline_chksum,
-            self.algsig_chksum)
+            self.algsig_chksum,
+            validate)
 
     def encode(self, data_bytes):
         return pyeclib_c.encode(self.handle, data_bytes)
@@ -136,7 +138,8 @@ class ECPyECLibDriver(object):
 
 class ECNullDriver(object):
 
-    def __init__(self, k, m, hd, ec_type=None, chksum_type=None):
+    def __init__(self, k, m, hd, ec_type=None, chksum_type=None,
+                 validate=False):
         self.k = k
         self.m = m
         self.hd = hd
@@ -173,7 +176,8 @@ class ECNullDriver(object):
 #
 class ECStripingDriver(object):
 
-    def __init__(self, k, m, hd, ec_type=None, chksum_type=None):
+    def __init__(self, k, m, hd, ec_type=None, chksum_type=None,
+                 validate=False):
         """Stripe an arbitrary-sized string into k fragments
         :param k: the number of data fragments to stripe
         :param m: the number of parity fragments to stripe
diff --git a/pyeclib/ec_iface.py b/pyeclib/ec_iface.py
index 2b459d6..202657d 100644
--- a/pyeclib/ec_iface.py
+++ b/pyeclib/ec_iface.py
@@ -112,6 +112,7 @@ class ECDriver(object):
         self.hd = -1
         self.ec_type = None
         self.chksum_type = None
+        self.validate = False
         for (key, value) in kwargs.items():
             if key == "k":
                 try:
@@ -144,6 +145,9 @@ class ECDriver(object):
                 else:
                     raise ECDriverError(
                         "%s is not a valid checksum type for PyECLib!" % value)
+            elif key == "validate":
+                # validate if the ec type is available (runtime check)
+                self.validate = value
 
         if self.hd == -1:
             self.hd = self.m
@@ -159,7 +163,10 @@ class ECDriver(object):
             m=self.m,
             hd=self.hd,
             ec_type=self.ec_type,
-            chksum_type=self.chksum_type)
+            chksum_type=self.chksum_type,
+            validate=int(self.validate)
+        )
+
         #
         # Verify that the imported library implements the required functions
         #
@@ -471,12 +478,14 @@ def _PyECLibValidECTypes():
     for _type in ALL_EC_TYPES:
         try:
             if _type is 'shss':
-                ECDriver(k=10, m=4, ec_type=_type)
+                _m = 4
             else:
-                ECDriver(k=10, m=5, ec_type=_type)
+                _m = 5
+            driver = ECDriver(k=10, m=_m, ec_type=_type, validate=True)
             available_ec_types.append(_type)
-        except Exception:
-            pass
+        except:
+            # ignore any errors, assume backend not available
+            continue
     return available_ec_types
 
 
diff --git a/src/c/pyeclib_c/pyeclib_c.c b/src/c/pyeclib_c/pyeclib_c.c
index ea6ac30..d96681d 100644
--- a/src/c/pyeclib_c/pyeclib_c.c
+++ b/src/c/pyeclib_c/pyeclib_c.c
@@ -24,6 +24,8 @@
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <stdio.h>
+#include <paths.h>
 #include <Python.h>
 #include <math.h>
 #include <bytesobject.h>
@@ -188,13 +190,39 @@ pyeclib_c_seterr(int ret, const char * prefix)
     PyErr_SetString(eo, err);
 }
 
+static int stderr_fd;
+static fpos_t stderr_fpos;
+#ifndef _PATH_DEVNULL
+#define _PATH_DEVNULL "/dev/null"
+#endif
+
+static void redirect_stderr(void)
+{
+    fflush(stderr);
+    fgetpos(stderr, &stderr_fpos);
+    stderr_fd = dup(fileno(stderr));
+    freopen(_PATH_DEVNULL, "w", stderr);
+}
+
+static void restore_stderr(void)
+{
+    fflush(stderr);
+    dup2(stderr_fd, fileno(stderr));
+    close(stderr_fd);
+    clearerr(stderr);
+    fsetpos(stderr, &stderr_fpos);        /* for C9X */
+}
+
 /**
  * Constructor method for creating a new pyeclib object using the given parameters.
  *
  * @param k integer number of data elements
  * @param m integer number of checksum elements
- * @param w integer word size in bytes
+ * @param hd hamming distance
  * @param backend_id erasure coding backend
+ * @param use_inline_chksum type of inline fragment header checksum
+ * @param use_algsig_chksum use algorithmic signature for fragment header checksum
+ * @param validate only validate backend and params, close handle immediately
  * @return pointer to PyObject or NULL on error
  */
 static PyObject *
@@ -202,12 +230,14 @@ pyeclib_c_init(PyObject *self, PyObject *args)
 {
   pyeclib_t *pyeclib_handle = NULL;
   PyObject *pyeclib_obj_handle = NULL;
-  int k, m, hd=0;
+  int k, m, hd = 0, validate = 0;
   int use_inline_chksum = 0, use_algsig_chksum = 0;
   const ec_backend_id_t backend_id;
 
   /* Obtain and validate the method parameters */
-  if (!PyArg_ParseTuple(args, "iii|iii", &k, &m, &backend_id, &hd, &use_inline_chksum, &use_algsig_chksum)) {
+  if (!PyArg_ParseTuple(args, "iii|iiiii",
+                        &k, &m, &backend_id, &hd, &use_inline_chksum,
+                        &use_algsig_chksum, &validate)) {
     pyeclib_c_seterr(-EINVALIDPARAMS, "pyeclib_c_init ERROR: ");
     return NULL;
   }
@@ -216,7 +246,7 @@ pyeclib_c_init(PyObject *self, PyObject *args)
   pyeclib_handle = (pyeclib_t *) alloc_zeroed_buffer(sizeof(pyeclib_t));
   if (NULL == pyeclib_handle) {
     pyeclib_c_seterr(-ENOMEM, "pyeclib_c_init ERROR: ");
-    goto error;
+    goto cleanup;
   }
 
   pyeclib_handle->ec_args.k = k;
@@ -224,10 +254,13 @@ pyeclib_c_init(PyObject *self, PyObject *args)
   pyeclib_handle->ec_args.hd = hd;
   pyeclib_handle->ec_args.ct = use_inline_chksum ? CHKSUM_CRC32 : CHKSUM_NONE;
 
+  if (validate)
+    redirect_stderr();
+
   pyeclib_handle->ec_desc = liberasurecode_instance_create(backend_id, &(pyeclib_handle->ec_args));  
   if (pyeclib_handle->ec_desc <= 0) {
     pyeclib_c_seterr(-EINVALIDPARAMS, "pyeclib_c_init ERROR: ");
-    goto error; 
+    goto cleanup;
   }
 
   /* Prepare the python object to return */
@@ -235,27 +268,28 @@ pyeclib_c_init(PyObject *self, PyObject *args)
   pyeclib_obj_handle = PyCapsule_New(pyeclib_handle, PYECC_HANDLE_NAME,
                                      pyeclib_c_destructor);
 #else
-  pyeclib_obj_handle = PyCObject_FromVoidPtrAndDesc(pyeclib_handle,
-                         (void *) PYECC_HANDLE_NAME,
-             pyeclib_c_destructor);
+  pyeclib_obj_handle = PyCObject_FromVoidPtrAndDesc(
+                                     pyeclib_handle, (void *) PYECC_HANDLE_NAME,
+                                     pyeclib_c_destructor);
 #endif /* Py_CAPSULE_H */
 
   /* Clean up the allocated memory on error, or update the ref count */
   if (pyeclib_obj_handle == NULL) {
     pyeclib_c_seterr(-EINVALIDPARAMS, "pyeclib_c_init ERROR: ");
-    goto error;
+    goto cleanup;
   } else {
     Py_INCREF(pyeclib_obj_handle);
   }
   
-  goto exit;
+exit:
+  if (validate)
+    restore_stderr();
+  return pyeclib_obj_handle;
 
-error:
+cleanup:
   check_and_free_buffer(pyeclib_handle);
   pyeclib_obj_handle = NULL;
-
-exit:  
-  return pyeclib_obj_handle;
+  goto exit;
 }