open_by_handle: add -s option to sleep and keep files open by handle

This feature is needed for tests that need to open file by handle and
then perform operations while that file is open. This will be used by
an overlay test to keep disconnected dentries in dcache.

Usage: open_by_handle -s <test_dir>

On success, the program will run until it gets a terminating signal.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

diff --git a/src/open_by_handle.c b/src/open_by_handle.c
index d3beb78496f9a2ae9079340f54439021fb349fbf..f5be2350e3fdefd447edb419467e812b550ea8fd 100644 (file)
--- a/src/open_by_handle.c
+++ b/src/open_by_handle.c
@@ -27,7 +27,7 @@
 
 /*
 
-usage: open_by_handle [-cludmrwapknh] [<-i|-o> <handles_file>] <test_dir> [num_files]
+usage: open_by_handle [-cludmrwapknhs] [<-i|-o> <handles_file>] <test_dir> [num_files]
 
 Examples:
 
@@ -48,9 +48,9 @@ Examples:
    open_by_handle -p -o <handles_file> <test_dir> [N]
 
 4. Read file handles from file and open files by handle without
-   dropping caches beforehand:
+   dropping caches beforehand. Sleep afterhand to keep files open:
 
-   open_by_handle -np -i <handles_file> <test_dir> [N]
+   open_by_handle -nps -i <handles_file> <test_dir> [N]
 
 5. Get file handles for existing test set, write data to files,
    drop caches, open all files by handle, read and verify written
@@ -112,7 +112,7 @@ struct handle {
 
 void usage(void)
 {
-       fprintf(stderr, "usage: open_by_handle [-cludmrwapknh] [<-i|-o> <handles_file>] <test_dir> [num_files]\n");
+       fprintf(stderr, "usage: open_by_handle [-cludmrwapknhs] [<-i|-o> <handles_file>] <test_dir> [num_files]\n");
        fprintf(stderr, "\n");
        fprintf(stderr, "open_by_handle -c <test_dir> [N] - create N test files under test_dir, try to get file handles and exit\n");
        fprintf(stderr, "open_by_handle    <test_dir> [N] - get file handles of test files, drop caches and try to open by handle\n");
@@ -128,6 +128,7 @@ void usage(void)
        fprintf(stderr, "open_by_handle -p <test_dir>     - create/delete and try to open by handle also test_dir itself\n");
        fprintf(stderr, "open_by_handle -i <handles_file> <test_dir> [N] - read test files handles from file and try to open by handle\n");
        fprintf(stderr, "open_by_handle -o <handles_file> <test_dir> [N] - get file handles of test files and write handles to file\n");
+       fprintf(stderr, "open_by_handle -s <test_dir> [N] - wait in sleep loop after opening files by handle to keep them open\n");
        exit(EXIT_FAILURE);
 }
 
@@ -148,12 +149,12 @@ int main(int argc, char **argv)
        int     numfiles = 1;
        int     create = 0, delete = 0, nlink = 1, move = 0;
        int     rd = 0, wr = 0, wrafter = 0, parent = 0;
-       int     keepopen = 0, drop_caches = 1;
+       int     keepopen = 0, drop_caches = 1, sleep_loop = 0;
 
        if (argc < 2)
                usage();
 
-       while ((c = getopt(argc, argv, "cludmrwapknhi:o:")) != -1) {
+       while ((c = getopt(argc, argv, "cludmrwapknhi:o:s")) != -1) {
                switch (c) {
                case 'c':
                        create = 1;
@@ -209,6 +210,9 @@ int main(int argc, char **argv)
                                return EXIT_FAILURE;
                        }
                        break;
+               case 's':
+                       sleep_loop = 1;
+                       break;
                default:
                        fprintf(stderr, "illegal option '%s'\n", argv[optind]);
                case 'h':
@@ -478,7 +482,8 @@ int main(int argc, char **argv)
                                perror(fname);
                                return EXIT_FAILURE;
                        }
-                       close(fd);
+                       if (!sleep_loop)
+                               close(fd);
                        continue;
                } else if (!nlink && !keepopen && fd < 0 && (errno == ENOENT || errno == ESTALE)) {
                        continue;
@@ -529,7 +534,8 @@ int main(int argc, char **argv)
                                        return EXIT_FAILURE;
                                }
                        }
-                       close(fd);
+                       if (!sleep_loop)
+                               close(fd);
                } else if (nlink || !(errno == ENOENT || errno == ESTALE)) {
                        printf("open_by_handle(%s) returned %d incorrectly on %s dir!\n",
                                        dname, errno,
@@ -540,5 +546,13 @@ int main(int argc, char **argv)
 
        if (failed)
                return EXIT_FAILURE;
+
+       /*
+        * Sleep keeping files open by handle - the program need to be killed
+        * to release the open files.
+        */
+       while (sleep_loop)
+               sleep(1);
+
        return EXIT_SUCCESS;
 }