ec: Fix posix compliance failures

This patch solves some problems that caused dispersed volumes to not
pass posix smoke tests:

* Problems in open/create with O_WRONLY
    Opening files with -w- permissions using O_WRONLY returned an EACCES
    error because internally O_WRONLY was replaced with O_RDWR.

* Problems with entrylk on renames.
    When source and destination were the same, ec tried to acquire
    the same entrylk twice, causing a deadlock.

* Overwrite of a variable when reordering locks.
    On a rename, if the second lock needed to be placed at the beggining
    of the list, the 'lock' variable was overwritten and later its timer
    was cancelled, cancelling the incorrect one.

* Handle O_TRUNC in open.
    When O_TRUNC was received in an open call, it was blindly propagated
    to child subvolumes. This caused a discrepancy between real file
    size and the size stored into trusted.ec.size xattr. This has been
    solved by removing O_TRUNC from open and later calling ftruncate.

This is a backport of http://review.gluster.org/9420

Change-Id: I20c3d6e1c11be314be86879be54b728e01013798
BUG: 1159471
Signed-off-by: Xavier Hernandez <xhernandez@datalab.es>
Reviewed-on: http://review.gluster.org/9501
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Dan Lambright <dlambrig@redhat.com>
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Reviewed-by: Raghavendra Bhat <raghavendra@redhat.com>

2 files changed, 97 insertions, 0 deletions

diff --git a/tests/bugs/bug-1161886/bug-1161886.c b/tests/bugs/bug-1161886/bug-1161886.c
new file mode 100644
index 00000000000..036f4ad1cc7
--- /dev/null
+++ b/tests/bugs/bug-1161886/bug-1161886.c
@@ -0,0 +1,53 @@
+
+#include <stdio.h>
+#include "glfs.h"
+#include "glfs-handles.h"
+
+int
+main (int argc, char *argv[])
+{
+        glfs_t    *fs = NULL;
+        glfs_fd_t *fd = NULL;
+        int        ret = 1;
+
+        if (argc != 4) {
+                fprintf (stderr, "Syntax: %s <host> <volname> <file>\n", argv[0]);
+                return 1;
+        }
+
+        fs = glfs_new (argv[2]);
+        if (!fs) {
+                fprintf (stderr, "glfs_new: returned NULL\n");
+                return 1;
+        }
+
+        ret = glfs_set_volfile_server (fs, "tcp", argv[1], 24007);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_set_volfile_server: retuned %d\n", ret);
+                goto out;
+        }
+        ret = glfs_set_logging (fs, "/dev/null", 7);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_set_logging: returned %d\n", ret);
+                goto out;
+        }
+        ret = glfs_init (fs);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_init: returned %d\n", ret);
+                goto out;
+        }
+
+        fd = glfs_open (fs, argv[3], O_RDWR | O_TRUNC);
+        if (fd == NULL) {
+                fprintf (stderr, "glfs_open: returned NULL\n");
+                goto out;
+        }
+        glfs_close(fd);
+
+        ret = 0;
+
+out:
+        glfs_fini (fs);
+
+        return ret;
+}
diff --git a/tests/bugs/bug-1161886/bug-1161886.t b/tests/bugs/bug-1161886/bug-1161886.t
new file mode 100644
index 00000000000..3911038cd5f
--- /dev/null
+++ b/tests/bugs/bug-1161886/bug-1161886.t
@@ -0,0 +1,44 @@
+#!/bin/bash
+
+. $(dirname $0)/../../include.rc
+. $(dirname $0)/../../volume.rc
+
+function check_ec_size
+{
+    local res
+
+    for i in {0..2}; do
+        res=$(( `getfattr -n trusted.ec.size -e hex $B0/$V0$i/$1 | sed -n "s/^trusted.ec.size=//p"` ))
+        if [ "x$res" == "x" -o "$res" != "$2" ]; then
+            echo "N"
+            return 0
+        fi
+    done
+    echo "Y"
+    return 0
+}
+
+cleanup
+
+TEST glusterd
+TEST pidof glusterd
+TEST $CLI volume create $V0 redundancy 1 $H0:$B0/${V0}{0..2}
+EXPECT "Created" volinfo_field $V0 'Status'
+TEST $CLI volume start $V0
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "Started" volinfo_field $V0 'Status'
+TEST glusterfs --entry-timeout=0 --attribute-timeout=0 --volfile-id=/$V0 --volfile-server=$H0 $M0
+EXPECT_WITHIN $CHILD_UP_TIMEOUT "3" ec_child_up_count $V0 0
+
+TEST dd if=/dev/zero of=$M0/file1 bs=4k count=1
+TEST mv $M0/file1 $M0/file2
+TEST ! stat $M0/file1
+TEST stat $M0/file2
+
+TEST gcc -Wall -O2 -I api/src -o $(dirname $0)/bug-1161886 $(dirname $0)/bug-1161886.c -lgfapi
+TEST $(dirname $0)/bug-1161886 $H0 $V0 /file2
+EXPECT "^0$" stat -c "%s" $M0/file2
+EXPECT "^Y$" check_ec_size file2 0
+
+rm -f $(dirname $0)/bug-1161886
+
+cleanup