libap: use util_lockfile and remove liblockfile dependency

Now that we have a utility library for file locking, remove all
calls to liblockfile functions from libap and remove all links to
the library from the current users of the libap liblockfile
implementation (ap_tools/ap-check and zdev).

Fixes: https://github.com/ibm-s390-linux/s390-tools/issues/142
Suggested-by: Luca BRUNO <luca.bruno@coreos.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

README.md

@@ -319,7 +319,6 @@ build options:
 |                |                    | pvattest                              |
 | libxml2        | `HAVE_LIBXML2`     | libkmipclient                         |
 | systemd        | `HAVE_SYSTEMD`     | hsavmcore                             |
-| liblockfile    | `HAVE_LOCKFILE`    | ap-check                              |
 | libudev        | `HAVE_LIBUDEV`     | cpacfstatsd                           |
 
 This table lists additional build or install options:
@@ -513,8 +512,7 @@ the different tools are provided:
   GNU awk for the build process.
 
 * ap-check:
-  For building the ap-check mdevctl callout utility you need liblockfile
-  version 1.14 or newer installed (liblockfile-devel.rpm).  Also required is
-  json-c version 0.13 or newer (json-c-devel.rpm).
-  Tip: you may skip ap-check build by adding `HAVE_LOCKFILE=0` or `HAVE_JSONC=0`
-  to the make invocation.
+  For building the ap-check mdevctl callout utility you need json-c version
+  0.13 or newer (json-c-devel.rpm).
+  Tip: you may skip ap-check build by adding `HAVE_JSONC=0` to the make
+  invocation.

ap_tools/Makefile

@@ -7,21 +7,14 @@ MDEVCTL_CALLOUTS = /etc/mdevctl.d/scripts.d/callouts/
 libs =	$(rootdir)/libap/libap.a \
 	$(rootdir)/libutil/libutil.a
 
-ifeq (${HAVE_LOCKFILE},0)
-all:
-	$(SKIP) HAVE_LOCKFILE=0
-
-install:
-	$(SKIP) HAVE_LOCKFILE=0
-
-else ifeq (${HAVE_JSONC},0)
+ifeq (${HAVE_JSONC},0)
 all:
 	$(SKIP) HAVE_JSONC=0
 
 install:
 	$(SKIP) HAVE_JSONC=0
 else
-LDLIBS += -llockfile -ljson-c
+LDLIBS += -ljson-c
 
 all: ap-check
 

ap_tools/ap-check.c

@@ -133,7 +133,7 @@ static void ap_check_cleanup(struct ap_check_anchor *anc)
 	if (anc->dev)
 		vfio_ap_device_free(anc->dev);
 	if (anc->cleanup_lock)
-		ap_release_lock();
+		ap_release_lock_callout();
 }
 
 /*
@@ -775,7 +775,7 @@ out:
  */
 static int ap_check_handle_post(void)
 {
-	return ap_release_lock();
+	return ap_release_lock_callout();
 }
 
 /* For the specified device, print the attributes to stdout in JSON format */

include/lib/ap.h

@@ -90,5 +90,6 @@ void ap_list_remove_all(struct util_list *list);
 int ap_get_lock(void);
 int ap_get_lock_callout(void);
 int ap_release_lock(void);
+int ap_release_lock_callout(void);
 
 #endif /* LIB_AP_H */

libap/Makefile

@@ -2,17 +2,6 @@ include ../common.mak
 
 lib = libap.a
 
-check-dep-lock:
-	touch check-dep-lock
-ifneq (${HAVE_LOCKFILE},0)
-	$(call check_dep, \
-		"libap", \
-		"lockfile.h", \
-		"liblockfile-devel", \
-		"HAVE_LOCKFILE=0")
-ALL_CPPFLAGS += -DHAVE_LOCKFILE
-endif
-
 check-dep-json:
 	touch check-dep-json
 ifneq (${HAVE_JSONC},0)
@@ -29,7 +18,7 @@ objects = ap.o
 
 $(lib): $(objects)
 
-$(objects): check-dep-lock check-dep-json
+$(objects): check-dep-json
 
 install: all
 

libap/ap.c

@@ -22,13 +22,10 @@
 #include <json-c/json.h>
 #endif /* HAVE_JSONC */
 
-#ifdef HAVE_LOCKFILE
-#include <lockfile.h>
-#endif /* HAVE_LOCKFILE */
-
 #include "lib/ap.h"
 #include "lib/util_file.h"
 #include "lib/util_libc.h"
+#include "lib/util_lockfile.h"
 #include "lib/util_panic.h"
 #include "lib/util_path.h"
 #include "lib/util_udev.h"
@@ -701,33 +698,28 @@ void ap_list_remove_all(struct util_list *list)
 	}
 }
 
-#ifdef HAVE_LOCKFILE
-static int ap_lockfile_create(int flags)
-{
-	return lockfile_create(AP_LOCKFILE, AP_LOCK_RETRIES, flags);
-}
-
 /**
- * Acquire the ap config lock using this process PID (L_PID)
+ * Acquire the ap config lock using this Process ID
+ *
+ * @retval         0          Lock acquired on behalf of this process
  *
- * @retval         0          Lock successfully acquired on behalf of L_PID
  * @retval         != 0       Error, lock was not obtained
  */
 int ap_get_lock(void)
 {
-	return ap_lockfile_create(L_PID);
+	return util_lockfile_lock(AP_LOCKFILE, AP_LOCK_RETRIES);
 }
 
 /**
- * Acquire the ap config lock using the parent process PID (L_PPID) -- intended
- * for use by the mdevctl callout ap-check utility
+ * Acquire the ap config lock using the Parent Process ID -- intended for use
+ * by the mdevctl callout ap-check utility
  *
- * @retval         0          Lock successfully acquired on behalf of L_PPID
+ * @retval         0          Lock acquired on behalf of parent process
  * @retval         != 0       Error, lock was not obtained
  */
 int ap_get_lock_callout(void)
 {
-	return ap_lockfile_create(L_PPID);
+	return util_lockfile_parent_lock(AP_LOCKFILE, AP_LOCK_RETRIES);
 }
 
 /**
@@ -738,23 +730,10 @@ int ap_get_lock_callout(void)
  */
 int ap_release_lock(void)
 {
-	return lockfile_remove(AP_LOCKFILE);
-}
-#else
-/* If no liblockfile, actions are performed without acquiring the file lock */
-int ap_get_lock(void)
-{
-	return 0;
+	return util_lockfile_release(AP_LOCKFILE);
 }
 
-int ap_get_lock_callout(void)
+int ap_release_lock_callout(void)
 {
-	return 0;
+	return util_lockfile_parent_release(AP_LOCKFILE);
 }
-
-int ap_release_lock(void)
-{
-	return 0;
-}
-
-#endif /* HAVE_LOCKFILE */

zdev/src/Makefile

@@ -81,9 +81,6 @@ lszdev_objects += generic_ccw.o
 
 all: chzdev lszdev zdev_id
 
-ifneq (${HAVE_LOCKFILE}, 0)
-LDLIBS += -llockfile
-endif
 ifneq (${HAVE_JSONC}, 0)
 LDLIBS += -ljson-c
 endif