tests: add seek program for testing SEEK_DATA/SEEK_HOLE over FUSE

Note that this only works on Linux kernel 4.5 and newer. The program is
not run by a test-case because of this.

BUG: 1220173
Change-Id: Ifdee3c793e33f9d763940130e8d01a61eae5498a
Signed-off-by: Niels de Vos <ndevos@redhat.com>
Reviewed-on: http://review.gluster.org/13291
Smoke: Gluster Build System <jenkins@build.gluster.com>
CentOS-regression: Gluster Build System <jenkins@build.gluster.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>

2 files changed, 92 insertions, 0 deletions

diff --git a/tests/basic/fuse/Makefile.am b/tests/basic/fuse/Makefile.am
new file mode 100644
index 00000000000..c446d253228
--- /dev/null
+++ b/tests/basic/fuse/Makefile.am
@@ -0,0 +1,12 @@
+CFLAGS   = -Wall -g
+LDFLAGS  =
+
+BINARIES = seek
+
+%: %.c
+	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^
+
+all: $(BINARIES)
+
+clean:
+	-$(RM) $(BINARIES)
diff --git a/tests/basic/fuse/seek.c b/tests/basic/fuse/seek.c
new file mode 100644
index 00000000000..e4db41c03d7
--- /dev/null
+++ b/tests/basic/fuse/seek.c
@@ -0,0 +1,80 @@
+/* seek.c - use lseek() to find holes in a file
+ *
+ * Author: Niels de Vos <ndevos@redhat.com>
+ */
+
+/* needed for SEEK_HOLE/SEEK_DATA */
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+int
+main (int argc, char **argv)
+{
+        int          ret        = EXIT_SUCCESS;
+        int          fd         = -1;
+        char        *filename   = NULL;
+        struct stat  st         = { 0, };
+        off_t        hole_start = 0;
+        off_t        hole_end   = 0;
+
+        if (argc != 2) {
+                fprintf (stderr, "Invalid argument, use %s <file>\n", argv[0]);
+                return EXIT_FAILURE;
+        }
+
+        filename = argv[1];
+
+        fd = open (filename, O_RDONLY);
+        if (fd <= 0) {
+                perror ("open");
+                return EXIT_FAILURE;
+        }
+
+        if (fstat (fd, &st)) {
+                perror ("fstat");
+                return EXIT_FAILURE;
+        }
+
+        while (hole_end < st.st_size) {
+                hole_start = lseek (fd, hole_end, SEEK_HOLE);
+                if (hole_start == -1 && errno == ENXIO) {
+                        /* no more holes */
+                        break;
+                } else if (hole_start == -1 && errno == ENOTSUP) {
+                        /* SEEK_HOLE is not supported */
+                        perror ("lseek(SEEK_HOLE)");
+                        ret = EXIT_FAILURE;
+                        break;
+                } else if (hole_start == -1) {
+			perror ("no more holes");
+			break;
+		}
+
+                hole_end = lseek (fd, hole_start, SEEK_DATA);
+                if (hole_end == -1 && errno == ENXIO) {
+                        /* no more data */
+                        break;
+                } else if (hole_end == -1 && errno == ENOTSUP) {
+                        /* SEEK_DATA is not supported */
+                        perror ("lseek(SEEK_DATA)");
+                        ret = EXIT_FAILURE;
+                        break;
+                }
+
+                printf ("HOLE found: %ld - %ld%s\n", hole_start, hole_end,
+                         (hole_end == st.st_size) ? " (EOF)" : "");
+        }
+
+        close (fd);
+
+        return ret;
+}