Use an enum to represent the return code and exit status of
multipath and its most important subroutine, configure().
This clarifies the confusing use of booleans and status
codes a bit, hopefully.
This patch doesn't introduce a change in behavior.
Signed-off-by: Martin Wilck <mwilck@xxxxxxxx>
---
multipath/main.c | 120 ++++++++++++++++++++++++++---------------------
1 file changed, 66 insertions(+), 54 deletions(-)
diff --git a/multipath/main.c b/multipath/main.c
index eb087482..e437746d 100644
--- a/multipath/main.c
+++ b/multipath/main.c
@@ -68,6 +68,19 @@ int logsink;
struct udev *udev;
struct config *multipath_conf;
+/*
+ * Return values of configure(), print_cmd_valid(), and main().
+ * RTVL_{YES,NO} are synonyms for RTVL_{OK,FAIL} for the CMD_VALID_PATH case.
+ */
+enum {
+ RTVL_OK = 0,
+ RTVL_YES = RTVL_OK,
+ RTVL_FAIL = 1,
+ RTVL_NO = RTVL_FAIL,
+ RTVL_MAYBE, /* only used internally, never returned */
+ RTVL_RETRY, /* returned by configure(), not by main() */
+};
+
struct config *get_multipath_config(void)
{
return multipath_conf;
@@ -475,15 +488,14 @@ retry:
static int print_cmd_valid(int k, const vector pathvec,
struct config *conf)
{
- static const int vals[] = { 1, 0, 2 };
int wait = FIND_MULTIPATHS_NEVER;
struct timespec until;
struct path *pp;
- if (k < 0 || k >= (sizeof(vals) / sizeof(int)))
- return 1;
+ if (k != RTVL_YES && k != RTVL_NO && k != RTVL_MAYBE)
+ return RTVL_NO;
- if (k == 2) {
+ if (k == RTVL_MAYBE) {
/*
* Caller ensures that pathvec[0] is the path to
* examine.
@@ -493,7 +505,7 @@ static int print_cmd_valid(int k, const vector pathvec,
wait = find_multipaths_check_timeout(
pp, pp->find_multipaths_timeout, &until);
if (wait != FIND_MULTIPATHS_WAITING)
- k = 1;
+ k = RTVL_NO;
} else if (pathvec != NULL && (pp = VECTOR_SLOT(pathvec, 0)))
wait = find_multipaths_check_timeout(pp, 0, &until);
if (wait == FIND_MULTIPATHS_WAITING)
@@ -501,8 +513,10 @@ static int print_cmd_valid(int k, const vector pathvec,
until.tv_sec, until.tv_nsec/1000);
else if (wait == FIND_MULTIPATHS_WAIT_DONE)
printf("FIND_MULTIPATHS_WAIT_UNTIL=\"0\"\n");
- printf("DM_MULTIPATH_DEVICE_PATH=\"%d\"\n", vals[k]);
- return k == 1;
+ printf("DM_MULTIPATH_DEVICE_PATH=\"%d\"\n",
+ k == RTVL_MAYBE ? 2 : k == RTVL_YES ? 1 : 0);
+ /* Never return RTVL_MAYBE */
+ return k == RTVL_NO ? RTVL_NO : RTVL_YES;
}
/*
@@ -524,12 +538,6 @@ static bool released_to_systemd(void)
return ret;
}
-/*
- * Return value:
- * -1: Retry
- * 0: Success
- * 1: Failure
- */
static int
configure (struct config *conf, enum mpath_cmds cmd,
enum devtypes dev_type, char *devpath)
@@ -537,7 +545,7 @@ configure (struct config *conf, enum mpath_cmds cmd,
vector curmp = NULL;
vector pathvec = NULL;
struct vectors vecs;
- int r = 1, rc;
+ int r = RTVL_FAIL, rc;
int di_flag = 0;
char * refwwid = NULL;
char * dev = NULL;
@@ -585,21 +593,23 @@ configure (struct config *conf, enum mpath_cmds cmd,
goto out;
}
if (cmd == CMD_REMOVE_WWID) {
- r = remove_wwid(refwwid);
- if (r == 0)
+ rc = remove_wwid(refwwid);
+ if (rc == 0) {
printf("wwid '%s' removed\n", refwwid);
- else if (r == 1) {
+ r = RTVL_OK;
+ } else if (rc == 1) {
printf("wwid '%s' not in wwids file\n",
refwwid);
- r = 0;
+ r = RTVL_OK;
}
goto out;
}
if (cmd == CMD_ADD_WWID) {
- r = remember_wwid(refwwid);
- if (r >= 0)
+ rc = remember_wwid(refwwid);
+ if (rc >= 0) {
printf("wwid '%s' added\n", refwwid);
- else
+ r = RTVL_OK;
+ } else
printf("failed adding '%s' to wwids file\n",
refwwid);
goto out;
@@ -614,13 +624,13 @@ configure (struct config *conf, enum mpath_cmds cmd,
*/
if (cmd == CMD_VALID_PATH) {
if (is_failed_wwid(refwwid) == WWID_IS_FAILED) {
- r = 1;
+ r = RTVL_NO;
goto print_valid;
}
if ((!find_multipaths_on(conf) &&
ignore_wwids_on(conf)) ||
check_wwids_file(refwwid, 0) == 0)
- r = 0;
+ r = RTVL_YES;
if (!ignore_wwids_on(conf))
goto print_valid;
/* At this point, either r==0 or find_multipaths_on. */
@@ -630,7 +640,7 @@ configure (struct config *conf, enum mpath_cmds cmd,
* Quick check if path is already multipathed.
*/
if (sysfs_is_multipathed(VECTOR_SLOT(pathvec, 0))) {
- r = 0;
+ r = RTVL_YES;
goto print_valid;
}
@@ -644,10 +654,10 @@ configure (struct config *conf, enum mpath_cmds cmd,
* Leave DM_MULTIPATH_DEVICE_PATH="0".
*/
if (released) {
- r = 1;
+ r = RTVL_NO;
goto print_valid;
}
- if (r == 0)
+ if (r == RTVL_YES)
goto print_valid;
/* find_multipaths_on: Fall through to path detection */
}
@@ -703,13 +713,12 @@ configure (struct config *conf, enum mpath_cmds cmd,
* the refwwid, or there is more than one path matching
* the refwwid, then the path is valid */
if (VECTOR_SIZE(curmp) != 0) {
- r = 0;
+ r = RTVL_YES;
goto print_valid;
} else if (VECTOR_SIZE(pathvec) > 1)
- r = 0;
+ r = RTVL_YES;
else
- /* Use r=2 as an indication for "maybe" */
- r = 2;
+ r = RTVL_MAYBE;
/*
* If opening the path with O_EXCL fails, the path
@@ -739,13 +748,14 @@ configure (struct config *conf, enum mpath_cmds cmd,
/*
* Check if we raced with multipathd
*/
- r = !sysfs_is_multipathed(VECTOR_SLOT(pathvec, 0));
+ r = sysfs_is_multipathed(VECTOR_SLOT(pathvec, 0)) ?
+ RTVL_YES : RTVL_NO;
}
goto print_valid;
}
if (cmd != CMD_CREATE && cmd != CMD_DRY_RUN) {
- r = 0;
+ r = RTVL_OK;
goto out;
}
@@ -754,7 +764,7 @@ configure (struct config *conf, enum mpath_cmds cmd,
*/
rc = coalesce_paths(&vecs, NULL, refwwid,
conf->force_reload, cmd);
- r = rc == CP_RETRY ? -1 : rc == CP_OK ? 0 : 1;
+ r = rc == CP_RETRY ? RTVL_RETRY : rc == CP_OK ? RTVL_OK : RTVL_FAIL;
print_valid:
if (cmd == CMD_VALID_PATH)
@@ -855,7 +865,7 @@ main (int argc, char *argv[])
int arg;
extern char *optarg;
extern int optind;
- int r = 1;
+ int r = RTVL_FAIL;
enum mpath_cmds cmd = CMD_CREATE;
enum devtypes dev_type = DEV_NONE;
char *dev = NULL;
@@ -866,7 +876,7 @@ main (int argc, char *argv[])
logsink = 0;
conf = load_config(DEFAULT_CONFIGFILE);
if (!conf)
- exit(1);
+ exit(RTVL_FAIL);
multipath_conf = conf;
conf->retrigger_tries = 0;
while ((arg = getopt(argc, argv, ":adcChl::FfM:v:p:b:BrR:itTquUwW")) != EOF ) {
@@ -877,7 +887,7 @@ main (int argc, char *argv[])
if (sizeof(optarg) > sizeof(char *) ||
!isdigit(optarg[0])) {
usage (argv[0]);
- exit(1);
+ exit(RTVL_FAIL);
}
conf->verbosity = atoi(optarg);
@@ -924,7 +934,7 @@ main (int argc, char *argv[])
if (conf->pgpolicy_flag == IOPOLICY_UNDEF) {
printf("'%s' is not a valid policy\n", optarg);
usage(argv[0]);
- exit(1);
+ exit(RTVL_FAIL);
}
break;
case 'r':
@@ -934,14 +944,14 @@ main (int argc, char *argv[])
conf->find_multipaths |= _FIND_MULTIPATHS_I;
break;
case 't':
- r = dump_config(conf, NULL, NULL);
+ r = dump_config(conf, NULL, NULL) ? RTVL_FAIL : RTVL_OK;
goto out_free_config;
case 'T':
cmd = CMD_DUMP_CONFIG;
break;
case 'h':
usage(argv[0]);
- exit(0);
+ exit(RTVL_OK);
case 'u':
cmd = CMD_VALID_PATH;
dev_type = DEV_UEVENT;
@@ -965,20 +975,20 @@ main (int argc, char *argv[])
case ':':
fprintf(stderr, "Missing option argument\n");
usage(argv[0]);
- exit(1);
+ exit(RTVL_FAIL);
case '?':
fprintf(stderr, "Unknown switch: %s\n", optarg);
usage(argv[0]);
- exit(1);
+ exit(RTVL_FAIL);
default:
usage(argv[0]);
- exit(1);
+ exit(RTVL_FAIL);
}
}
if (getuid() != 0) {
fprintf(stderr, "need to be root\n");
- exit(1);
+ exit(RTVL_FAIL);
}
if (optind < argc) {
@@ -1016,7 +1026,8 @@ main (int argc, char *argv[])
/* Failing here is non-fatal */
init_foreign(conf->multipath_dir);
if (cmd == CMD_USABLE_PATHS) {
- r = check_usable_paths(conf, dev, dev_type);
+ r = check_usable_paths(conf, dev, dev_type) ?
+ RTVL_FAIL : RTVL_OK;
goto out;
}
if (cmd == CMD_VALID_PATH &&
@@ -1032,7 +1043,7 @@ main (int argc, char *argv[])
if (fd == -1) {
condlog(3, "%s: daemon is not running", dev);
if (!systemd_service_enabled(dev)) {
- r = print_cmd_valid(1, NULL, conf);
+ r = print_cmd_valid(RTVL_NO, NULL, conf);
goto out;
}
} else
@@ -1046,9 +1057,9 @@ main (int argc, char *argv[])
switch(delegate_to_multipathd(cmd, dev, dev_type, conf)) {
case DELEGATE_OK:
- exit(0);
+ exit(RTVL_OK);
case DELEGATE_ERROR:
- exit(1);
+ exit(RTVL_FAIL);
case NOT_DELEGATED:
break;
}
@@ -1064,8 +1075,8 @@ main (int argc, char *argv[])
goto out;
}
if (dm_get_maps(curmp) == 0)
- r = replace_wwids(curmp);
- if (r == 0)
+ r = replace_wwids(curmp) ? RTVL_FAIL : RTVL_OK;
+ if (r == RTVL_OK)
printf("successfully reset wwids\n");
vector_foreach_slot_backwards(curmp, mpp, i) {
vector_del_slot(curmp, i);
@@ -1078,17 +1089,18 @@ main (int argc, char *argv[])
retries = conf->remove_retries;
if (conf->remove == FLUSH_ONE) {
if (dev_type == DEV_DEVMAP) {
- r = dm_suspend_and_flush_map(dev, retries);
+ r = dm_suspend_and_flush_map(dev, retries) ?
+ RTVL_FAIL : RTVL_OK;
} else
condlog(0, "must provide a map name to remove");
goto out;
}
else if (conf->remove == FLUSH_ALL) {
- r = dm_flush_maps(retries);
+ r = dm_flush_maps(retries) ? RTVL_FAIL : RTVL_OK;
goto out;
}
- while ((r = configure(conf, cmd, dev_type, dev)) < 0)
+ while ((r = configure(conf, cmd, dev_type, dev)) == RTVL_RETRY)
condlog(3, "restart multipath configuration process");
out:
@@ -1103,8 +1115,8 @@ out:
* multipath -u must exit with status 0, otherwise udev won't
* import its output.
*/
- if (cmd == CMD_VALID_PATH && dev_type == DEV_UEVENT && r == 1)
- r = 0;
+ if (cmd == CMD_VALID_PATH && dev_type == DEV_UEVENT && r == RTVL_NO)
+ r = RTVL_OK;
if (dev_type == DEV_UEVENT)
closelog();
--
2.19.1
--
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