The checkers code implicitly uses a sort-of OOP class/instance model,
but very clumsily. Separate the checker "class" and "instance" cleanly,
and do a few further cleanups (constifications etc) on the way.
Signed-off-by: Martin Wilck <mwilck@xxxxxxxx>
---
libmultipath/checkers.c | 137 ++++++++++++++++---------------
libmultipath/checkers.h | 23 ++----
libmultipath/checkers/directio.c | 2 +-
libmultipath/checkers/tur.c | 2 +-
libmultipath/print.c | 2 +-
libmultipath/propsel.c | 19 +++--
6 files changed, 92 insertions(+), 93 deletions(-)
diff --git a/libmultipath/checkers.c b/libmultipath/checkers.c
index 19c8ad58..7733471c 100644
--- a/libmultipath/checkers.c
+++ b/libmultipath/checkers.c
@@ -8,6 +8,19 @@
#include "checkers.h"
#include "vector.h"
+struct checker_class {
+ struct list_head node;
+ void *handle;
+ int refcount;
+ int sync;
+ char name[CHECKER_NAME_LEN];
+ int (*check)(struct checker *);
+ int (*init)(struct checker *); /* to allocate the context */
+ void (*free)(struct checker *); /* to free the context */
+ const char **msgtable;
+ short msgtable_size;
+};
+
char *checker_state_names[] = {
"wild",
"unchecked",
@@ -23,38 +36,30 @@ char *checker_state_names[] = {
static LIST_HEAD(checkers);
-char * checker_state_name (int i)
+const char *checker_state_name(int i)
{
return checker_state_names[i];
}
-int init_checkers (char *multipath_dir)
-{
- if (!add_checker(multipath_dir, DEFAULT_CHECKER))
- return 1;
- return 0;
-}
-
-struct checker * alloc_checker (void)
+static struct checker_class *alloc_checker_class(void)
{
- struct checker *c;
+ struct checker_class *c;
- c = MALLOC(sizeof(struct checker));
+ c = MALLOC(sizeof(struct checker_class));
if (c) {
INIT_LIST_HEAD(&c->node);
c->refcount = 1;
- c->fd = -1;
}
return c;
}
-void free_checker (struct checker * c)
+void free_checker_class(struct checker_class *c)
{
if (!c)
return;
c->refcount--;
if (c->refcount) {
- condlog(3, "%s checker refcount %d",
+ condlog(4, "%s checker refcount %d",
c->name, c->refcount);
return;
}
@@ -71,17 +76,17 @@ void free_checker (struct checker * c)
void cleanup_checkers (void)
{
- struct checker * checker_loop;
- struct checker * checker_temp;
+ struct checker_class *checker_loop;
+ struct checker_class *checker_temp;
list_for_each_entry_safe(checker_loop, checker_temp, &checkers, node) {
- free_checker(checker_loop);
+ free_checker_class(checker_loop);
}
}
-struct checker * checker_lookup (char * name)
+static struct checker_class *checker_class_lookup(const char *name)
{
- struct checker * c;
+ struct checker_class *c;
if (!name || !strlen(name))
return NULL;
@@ -92,14 +97,15 @@ struct checker * checker_lookup (char * name)
return NULL;
}
-struct checker * add_checker (char *multipath_dir, char * name)
+static struct checker_class *add_checker_class(const char *multipath_dir,
+ const char *name)
{
char libname[LIB_CHECKER_NAMELEN];
struct stat stbuf;
- struct checker * c;
+ struct checker_class *c;
char *errstr;
- c = alloc_checker();
+ c = alloc_checker_class();
if (!c)
return NULL;
snprintf(c->name, CHECKER_NAME_LEN, "%s", name);
@@ -158,12 +164,11 @@ struct checker * add_checker (char *multipath_dir, char * name)
c->name, c->msgtable_size);
done:
- c->fd = -1;
c->sync = 1;
list_add(&c->node, &checkers);
return c;
out:
- free_checker(c);
+ free_checker_class(c);
return NULL;
}
@@ -176,16 +181,16 @@ void checker_set_fd (struct checker * c, int fd)
void checker_set_sync (struct checker * c)
{
- if (!c)
+ if (!c || !c->cls)
return;
- c->sync = 1;
+ c->cls->sync = 1;
}
void checker_set_async (struct checker * c)
{
- if (!c)
+ if (!c || !c->cls)
return;
- c->sync = 0;
+ c->cls->sync = 0;
}
void checker_enable (struct checker * c)
@@ -204,11 +209,11 @@ void checker_disable (struct checker * c)
int checker_init (struct checker * c, void ** mpctxt_addr)
{
- if (!c)
+ if (!c || !c->cls)
return 1;
c->mpcontext = mpctxt_addr;
- if (c->init)
- return c->init(c);
+ if (c->cls->init)
+ return c->cls->init(c);
return 0;
}
@@ -220,15 +225,16 @@ void checker_clear (struct checker *c)
void checker_put (struct checker * dst)
{
- struct checker * src;
+ struct checker_class *src;
- if (!dst || !strlen(dst->name))
+ if (!dst)
return;
- src = checker_lookup(dst->name);
- if (dst->free)
- dst->free(dst);
+ src = dst->cls;
+
+ if (src && src->free)
+ src->free(dst);
checker_clear(dst);
- free_checker(src);
+ free_checker_class(src);
}
int checker_check (struct checker * c, int path_state)
@@ -243,32 +249,35 @@ int checker_check (struct checker * c, int path_state)
c->msgid = CHECKER_MSGID_DISABLED;
return PATH_UNCHECKED;
}
- if (!strncmp(c->name, NONE, 4))
+ if (!strncmp(c->cls->name, NONE, 4))
return path_state;
if (c->fd < 0) {
c->msgid = CHECKER_MSGID_NO_FD;
return PATH_WILD;
}
- r = c->check(c);
+ r = c->cls->check(c);
return r;
}
-int checker_selected (struct checker * c)
+int checker_selected(const struct checker *c)
{
if (!c)
return 0;
- if (!strncmp(c->name, NONE, 4))
- return 1;
- return (c->check) ? 1 : 0;
+ return c->cls != NULL;
}
const char *checker_name(const struct checker *c)
{
- if (!c)
+ if (!c || !c->cls)
return NULL;
- return c->name;
+ return c->cls->name;
+}
+
+int checker_is_sync(const struct checker *c)
+{
+ return c && c->cls && c->cls->sync;
}
static const char *generic_msg[CHECKER_LAST_GENERIC_MSGID] = {
@@ -295,8 +304,8 @@ static const char *_checker_message(const struct checker *c)
return generic_msg[c->msgid];
id = c->msgid - CHECKER_FIRST_MSGID;
- if (id < c->msgtable_size)
- return c->msgtable[id];
+ if (id < c->cls->msgtable_size)
+ return c->cls->msgtable[id];
return NULL;
}
@@ -309,7 +318,7 @@ const char *checker_message(const struct checker *c)
*buf = '\0';
else
snprintf(buf, sizeof(buf), "%s checker%s",
- c->name, msg);
+ c->cls->name, msg);
return buf;
}
@@ -320,31 +329,29 @@ void checker_clear_message (struct checker *c)
c->msgid = CHECKER_MSGID_NONE;
}
-void checker_get (char *multipath_dir, struct checker * dst, char * name)
+void checker_get(const char *multipath_dir, struct checker *dst,
+ const char *name)
{
- struct checker * src = NULL;
+ struct checker_class *src = NULL;
if (!dst)
return;
if (name && strlen(name)) {
- src = checker_lookup(name);
+ src = checker_class_lookup(name);
if (!src)
- src = add_checker(multipath_dir, name);
+ src = add_checker_class(multipath_dir, name);
}
- if (!src) {
- dst->check = NULL;
+ dst->cls = src;
+ if (!src)
return;
- }
- dst->fd = src->fd;
- dst->sync = src->sync;
- strncpy(dst->name, src->name, CHECKER_NAME_LEN);
- dst->msgid = src->msgid;
- dst->check = src->check;
- dst->init = src->init;
- dst->free = src->free;
- dst->msgtable = src->msgtable;
- dst->msgtable_size = src->msgtable_size;
- dst->handle = NULL;
+
src->refcount++;
}
+
+int init_checkers(const char *multipath_dir)
+{
+ if (!add_checker_class(multipath_dir, DEFAULT_CHECKER))
+ return 1;
+ return 0;
+}
diff --git a/libmultipath/checkers.h b/libmultipath/checkers.h
index 98fec2c4..c46f7ffa 100644
--- a/libmultipath/checkers.h
+++ b/libmultipath/checkers.h
@@ -116,32 +116,22 @@ enum {
CHECKER_MSGTABLE_SIZE = 100, /* max msg table size for checkers */
};
+struct checker_class;
struct checker {
- struct list_head node;
- void *handle;
- int refcount;
+ struct checker_class *cls;
int fd;
- int sync;
unsigned int timeout;
int disable;
- char name[CHECKER_NAME_LEN];
short msgid; /* checker-internal extra status */
void * context; /* store for persistent data */
void ** mpcontext; /* store for persistent data shared
multipath-wide. Use MALLOC if
you want to stuff data in. */
- int (*check)(struct checker *);
- int (*init)(struct checker *); /* to allocate the context */
- void (*free)(struct checker *); /* to free the context */
- const char**msgtable;
- short msgtable_size;
};
-char * checker_state_name (int);
-int init_checkers (char *);
+const char *checker_state_name(int);
+int init_checkers(const char *);
void cleanup_checkers (void);
-struct checker * add_checker (char *, char *);
-struct checker * checker_lookup (char *);
int checker_init (struct checker *, void **);
void checker_clear (struct checker *);
void checker_put (struct checker *);
@@ -152,11 +142,12 @@ void checker_set_fd (struct checker *, int);
void checker_enable (struct checker *);
void checker_disable (struct checker *);
int checker_check (struct checker *, int);
-int checker_selected (struct checker *);
+int checker_selected(const struct checker *);
+int checker_is_sync(const struct checker *);
const char *checker_name (const struct checker *);
const char *checker_message (const struct checker *);
void checker_clear_message (struct checker *c);
-void checker_get (char *, struct checker *, char *);
+void checker_get(const char *, struct checker *, const char *);
/* Prototypes for symbols exported by path checker dynamic libraries (.so) */
int libcheck_check(struct checker *);
diff --git a/libmultipath/checkers/directio.c b/libmultipath/checkers/directio.c
index c4a0712e..1b00b775 100644
--- a/libmultipath/checkers/directio.c
+++ b/libmultipath/checkers/directio.c
@@ -202,7 +202,7 @@ int libcheck_check (struct checker * c)
if (!ct)
return PATH_UNCHECKED;
- ret = check_state(c->fd, ct, c->sync, c->timeout);
+ ret = check_state(c->fd, ct, checker_is_sync(c), c->timeout);
switch (ret)
{
diff --git a/libmultipath/checkers/tur.c b/libmultipath/checkers/tur.c
index 8f4bdc8b..05e7bed6 100644
--- a/libmultipath/checkers/tur.c
+++ b/libmultipath/checkers/tur.c
@@ -323,7 +323,7 @@ int libcheck_check(struct checker * c)
if (!ct)
return PATH_UNCHECKED;
- if (c->sync)
+ if (checker_is_sync(c))
return tur_check(c->fd, c->timeout, &c->msgid);
/*
diff --git a/libmultipath/print.c b/libmultipath/print.c
index 7b610b94..fc40b0f0 100644
--- a/libmultipath/print.c
+++ b/libmultipath/print.c
@@ -615,7 +615,7 @@ static int
snprint_path_checker (char * buff, size_t len, const struct path * pp)
{
const struct checker * c = &pp->checker;
- return snprint_str(buff, len, c->name);
+ return snprint_str(buff, len, checker_name(c));
}
static int
diff --git a/libmultipath/propsel.c b/libmultipath/propsel.c
index fdb5953a..970a3b5c 100644
--- a/libmultipath/propsel.c
+++ b/libmultipath/propsel.c
@@ -479,26 +479,27 @@ check_rdac(struct path * pp)
int select_checker(struct config *conf, struct path *pp)
{
const char *origin;
- char *checker_name;
+ char *ckr_name;
struct checker * c = &pp->checker;
if (pp->detect_checker == DETECT_CHECKER_ON) {
origin = autodetect_origin;
if (check_rdac(pp)) {
- checker_name = RDAC;
+ ckr_name = RDAC;
goto out;
} else if (pp->tpgs > 0) {
- checker_name = TUR;
+ ckr_name = TUR;
goto out;
}
}
- do_set(checker_name, conf->overrides, checker_name, overrides_origin);
- do_set_from_hwe(checker_name, pp, checker_name, hwe_origin);
- do_set(checker_name, conf, checker_name, conf_origin);
- do_default(checker_name, DEFAULT_CHECKER);
+ do_set(checker_name, conf->overrides, ckr_name, overrides_origin);
+ do_set_from_hwe(checker_name, pp, ckr_name, hwe_origin);
+ do_set(checker_name, conf, ckr_name, conf_origin);
+ do_default(ckr_name, DEFAULT_CHECKER);
out:
- checker_get(conf->multipath_dir, c, checker_name);
- condlog(3, "%s: path_checker = %s %s", pp->dev, c->name, origin);
+ checker_get(conf->multipath_dir, c, ckr_name);
+ condlog(3, "%s: path_checker = %s %s", pp->dev,
+ checker_name(c), origin);
if (conf->checker_timeout) {
c->timeout = conf->checker_timeout;
condlog(3, "%s: checker timeout = %u s %s",
--
2.19.0
--
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