pkgtools

commit 945efae19305d4416f44b666b37340901d5055ce
parent ab213e6eb726133a978bb3d15bdcc42f42ca9129
Author: sin <sin@2f30.org>
Date:   Sun, 15 Jun 2014 22:38:57 +0100

Lock /var/pkg directly

No need for a separate lockfile.

Diffstat:
M
infopkg.c
 | 
5
+----
M
installpkg.c
 | 
5
+----
M
lock.c
 | 
61
++++++++++++++-----------------------------------------------
M
removepkg.c
 | 
5
+----
M
util.h
 | 
3
+--

5 files changed, 18 insertions(+), 61 deletions(-)
diff --git a/infopkg.c b/infopkg.c
@@ -32,7 +32,6 @@ main(int argc, char *argv[])
 	char *prefix = "/";
 	char path[PATH_MAX];
 	int Oflag = 0;
-	int lockfd;
 	int i;
 	int r;
 
@@ -57,7 +56,7 @@ main(int argc, char *argv[])
 		return EXIT_FAILURE;
 	}
 
-	lockfd = lockdb();
+	lockdb();
 
 	dir = opendir("var/pkg");
 	if (!dir) {
@@ -82,8 +81,6 @@ main(int argc, char *argv[])
 
 	closedir(dir);
 
-	unlockdb(lockfd);
-
 	return EXIT_SUCCESS;
 }
 
diff --git a/installpkg.c b/installpkg.c
@@ -39,7 +39,6 @@ main(int argc, char *argv[])
 	char cwd[PATH_MAX];
 	char *prefix = "/";
 	int fflag = 0;
-	int lockfd;
 
 	ARGBEGIN {
 	case 'v':
@@ -67,7 +66,7 @@ main(int argc, char *argv[])
 		exit(EXIT_FAILURE);
 	}
 
-	lockfd = lockdb();
+	lockdb();
 
 	r = chdir(cwd);
 	if (r < 0) {
@@ -100,8 +99,6 @@ main(int argc, char *argv[])
 		exit(EXIT_FAILURE);
 	}
 
-	unlockdb(lockfd);
-
 	return EXIT_SUCCESS;
 }
 
diff --git a/lock.c b/lock.c
@@ -1,65 +1,32 @@
 /* See LICENSE file for copyright and license details. */
+#include <dirent.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <fcntl.h>
+#include <sys/types.h>
 #include <unistd.h>
 
-#define LOCKPATH "var/pkg/.lock"
-
 /* lock the package dabatase - assumes cwd is the root prefix */
-int
+void
 lockdb(void)
 {
-	struct flock fl;
-	int r;
-	int fd;
-
-	fl.l_type = F_WRLCK;
-	fl.l_whence = SEEK_SET;
-	fl.l_start = 0;
-	fl.l_len = 0;
-	fl.l_pid = getpid();
-
-	fd = open(LOCKPATH, O_WRONLY | O_CREAT, 0600);
-	if (fd < 0) {
-		fprintf(stderr, "failed to create lockfile: %s\n",
-			strerror(errno));
-		exit(EXIT_FAILURE);
-	}
+	DIR *dir;
 
-	r = fcntl(fd, F_SETLKW, &fl);
-	if (r < 0) {
-		fprintf(stderr, "failed to obtain lock: %s\n",
+	dir = opendir("var/pkg");
+	if (!dir) {
+		fprintf(stderr, "opendir %s: %s\n", "var/pkg",
 			strerror(errno));
 		exit(EXIT_FAILURE);
 	}
 
-	return fd;
-}
-
-/* unlock the package dabatase - assumes cwd is the root prefix */
-void
-unlockdb(int fd)
-{
-	struct flock fl;
-	int r;
-
-	fl.l_type = F_UNLCK;
-	fl.l_whence = SEEK_SET;
-	fl.l_start = 0;
-	fl.l_len = 0;
-	fl.l_pid = getpid();
-
-	r = fcntl(fd, F_SETLKW, &fl);
-	if (r < 0) {
-		fprintf(stderr, "failed to clear lock: %s\n",
-			strerror(errno));
+	if (flock(dirfd(dir), LOCK_EX | LOCK_NB) < 0) {
+		if (errno == EWOULDBLOCK)
+			fprintf(stderr, "package db already locked\n");
+		else
+			fprintf(stderr, "flock %s: %s\n", "var/pkg",
+				strerror(errno));
 		exit(EXIT_FAILURE);
 	}
-
-	close(fd);
-
-	unlink(LOCKPATH);
 }
diff --git a/removepkg.c b/removepkg.c
@@ -38,7 +38,6 @@ main(int argc, char *argv[])
 	struct dirent *dp;
 	char filename[PATH_MAX];
 	char *prefix = "/";
-	int lockfd;
 	int found = 0;
 	int r;
 	int i;
@@ -67,7 +66,7 @@ main(int argc, char *argv[])
 		return EXIT_FAILURE;
 	}
 
-	lockfd = lockdb();
+	lockdb();
 
 	dir = opendir("var/pkg");
 	if (!dir) {
@@ -107,8 +106,6 @@ main(int argc, char *argv[])
 
 	closedir(dir);
 
-	unlockdb(lockfd);
-
 	return EXIT_SUCCESS;
 }
 
diff --git a/util.h b/util.h
@@ -6,8 +6,7 @@
 
 extern char *argv0;
 
-int lockdb(void);
-void unlockdb(int);
+void lockdb(void);
 
 #undef strlcat
 size_t strlcat(char *, const char *, size_t);