Module Name: src
Committed By: jmmv
Date: Tue Mar 29 13:55:37 UTC 2011
Modified Files:
src/lib/libutil: pidfile.3 pidfile.c
src/tests/lib/libutil: t_pidfile.c
Log Message:
Extend pidfile(3) to support creating pid files in arbitrary locations.
If the argument provided to pidfile(3) contains a '/', then the value is
considered to be an absolute/relative path and the pid file is created
in the given location.
Otherwise, pidfile(3) behaves as before and treats the provided value as
a basename to construct a pid file in /var/run/<basename>.pid. This means
that to create a pid file named "foo.pid" in the current directory, one
must specify "./foo.pid".
To generate a diff of this commit:
cvs rdiff -u -r1.12 -r1.13 src/lib/libutil/pidfile.3
cvs rdiff -u -r1.8 -r1.9 src/lib/libutil/pidfile.c
cvs rdiff -u -r1.2 -r1.3 src/tests/lib/libutil/t_pidfile.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/libutil/pidfile.3
diff -u src/lib/libutil/pidfile.3:1.12 src/lib/libutil/pidfile.3:1.13
--- src/lib/libutil/pidfile.3:1.12 Wed May 5 22:05:31 2010
+++ src/lib/libutil/pidfile.3 Tue Mar 29 13:55:37 2011
@@ -1,4 +1,4 @@
-.\" $NetBSD: pidfile.3,v 1.12 2010/05/05 22:05:31 wiz Exp $
+.\" $NetBSD: pidfile.3,v 1.13 2011/03/29 13:55:37 jmmv Exp $
.\"
.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
.\" All rights reserved.
@@ -27,7 +27,7 @@
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
-.Dd May 4, 2010
+.Dd March 23, 2011
.Dt PIDFILE 3
.Os
.Sh NAME
@@ -38,34 +38,48 @@
.Sh SYNOPSIS
.In util.h
.Ft int
-.Fn pidfile "const char *basename"
+.Fn pidfile "const char *path"
.Sh DESCRIPTION
.Fn pidfile
-writes a file containing the process ID of the program to the
+creates a file containing the process ID of the caller program.
+The pid file can be used as a quick reference if
+the process needs to be sent a signal.
+When the program exits, the pid file is removed automatically, unless
+the program receives a fatal signal.
+.Pp
+If
+.Ar path
+is
+.Dv NULL
+or a plain basename (a name containing no directory components), the pid file
+is created in the
.Pa /var/run
directory.
The file name has the form
.Pa /var/run/basename.pid .
-If the
-.Ar basename
-argument is
+The basename part is either the value of
+.Ar path
+if it was not
.Dv NULL ,
-.Fn pidfile
-will determine the program name and use that instead.
+or the program name as returned by
+.Xr getprogname 3
+otherwise.
.Pp
-The pid file can be used as a quick reference if
-the process needs to be sent a signal.
-When the program exits, the pid file will be removed automatically, unless
-the program receives a fatal signal.
+If
+.Ar path
+is an absolute or relative path (i.e. it contains the
+.Sq /
+character),
+the pid file is created in the provided location.
.Pp
Note that only the first invocation of
.Fn pidfile
causes a pid file to be written; subsequent invocations have no effect
unless a new
-.Ar basename
+.Ar path
is supplied.
If called with a new
-.Ar basename ,
+.Ar path ,
.Fn pidfile
will remove the old pid file and write the new one.
.Sh RETURN VALUES
@@ -78,11 +92,13 @@
.Fn pidfile
function call appeared in
.Nx 1.5 .
+Support for creating pid files in any arbitrary path was added in
+.Nx 6.0 .
.Sh BUGS
.Fn pidfile
uses
.Xr atexit 3
-to ensure the pidfile is unlinked at program exit.
+to ensure the pid file is unlinked at program exit.
However, programs that use the
.Xr _exit 2
function (for example, in signal handlers)
Index: src/lib/libutil/pidfile.c
diff -u src/lib/libutil/pidfile.c:1.8 src/lib/libutil/pidfile.c:1.9
--- src/lib/libutil/pidfile.c:1.8 Mon Apr 28 20:23:03 2008
+++ src/lib/libutil/pidfile.c Tue Mar 29 13:55:37 2011
@@ -1,11 +1,11 @@
-/* $NetBSD: pidfile.c,v 1.8 2008/04/28 20:23:03 martin Exp $ */
+/* $NetBSD: pidfile.c,v 1.9 2011/03/29 13:55:37 jmmv Exp $ */
/*-
* Copyright (c) 1999 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
- * by Jason R. Thorpe and Matthias Scheler.
+ * by Jason R. Thorpe, Matthias Scheler and Julio Merino.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -31,90 +31,144 @@
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
-__RCSID("$NetBSD: pidfile.c,v 1.8 2008/04/28 20:23:03 martin Exp $");
+__RCSID("$NetBSD: pidfile.c,v 1.9 2011/03/29 13:55:37 jmmv Exp $");
#endif
#include <sys/param.h>
+
#include <paths.h>
+#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <util.h>
-static int pidfile_atexit_done;
static pid_t pidfile_pid;
-static char *pidfile_basename;
static char *pidfile_path;
-static void pidfile_cleanup(void);
+/* Deletes an existent pidfile iff it was created by this process. */
+static void
+pidfile_cleanup(void)
+{
-int
-pidfile(const char *basename)
+ if ((pidfile_path != NULL) && (pidfile_pid == getpid()))
+ (void) unlink(pidfile_path);
+}
+
+/* Registers an atexit(3) handler to delete the pidfile we have generated.
+ * We only register the handler when we create a pidfile, so we can assume
+ * that the pidfile exists.
+ *
+ * Returns 0 on success or -1 if the handler could not be registered. */
+static int
+register_atexit_handler(void)
{
- FILE *f;
+ static bool done = false;
- /*
- * Register handler which will remove the pidfile later.
- */
- if (!pidfile_atexit_done) {
+ if (!done) {
if (atexit(pidfile_cleanup) < 0)
return -1;
- pidfile_atexit_done = 1;
+ done = true;
}
- if (basename == NULL)
- basename = getprogname();
+ return 0;
+}
- /*
- * If pidfile has already been created for the supplied basename
- * we don't need to create a pidfile again.
- */
+/* Given a new pidfile name in 'path', deletes any previously-created pidfile
+ * if the previous file differs to the new one.
+ *
+ * If a previous file is deleted, returns 1, which means that a new pidfile
+ * must be created. Otherwise, this returns 0, which means that the existing
+ * file does not need to be touched. */
+static int
+cleanup_old_pidfile(const char* path)
+{
if (pidfile_path != NULL) {
- if (strcmp(pidfile_basename, basename) == 0)
+ if (strcmp(pidfile_path, path) != 0) {
+ pidfile_cleanup();
+
+ free(pidfile_path);
+ pidfile_path = NULL;
+
+ return 1;
+ } else
return 0;
- /*
- * Remove existing pidfile if it was created by this process.
- */
- pidfile_cleanup();
+ } else
+ return 1;
+}
- free(pidfile_path);
- pidfile_path = NULL;
- free(pidfile_basename);
- pidfile_basename = NULL;
- }
+/* Constructs a name for a pidfile in the default location (/var/run). If
+ * 'basename' is NULL, uses the name of the current program for the name of
+ * the pidfile.
+ *
+ * Returns a pointer to a dynamically-allocatd string containing the absolute
+ * path to the pidfile; NULL on failure. */
+static char *
+generate_varrun_path(const char *basename)
+{
+ char *path;
- pidfile_pid = getpid();
+ if (basename == NULL)
+ basename = getprogname();
- pidfile_basename = strdup(basename);
- if (pidfile_basename == NULL)
+ /* _PATH_VARRUN includes trailing / */
+ (void) asprintf(&path, "%s%s.pid", _PATH_VARRUN, basename);
+ return path;
+}
+
+/* Creates a pidfile with the provided name. The new pidfile is "registered"
+ * in the global variables pidfile_path and pidfile_pid so that any further
+ * call to pidfile(3) can check if we are recreating the same file or a new
+ * one.
+ *
+ * Returns 0 on success or -1 if there is any error. */
+static int
+create_pidfile(const char* path)
+{
+ FILE *f;
+
+ if (register_atexit_handler() == -1)
return -1;
- /* _PATH_VARRUN includes trailing / */
- (void) asprintf(&pidfile_path, "%s%s.pid", _PATH_VARRUN, basename);
- if (pidfile_path == NULL) {
- free(pidfile_basename);
- pidfile_basename = NULL;
+ if (cleanup_old_pidfile(path) == 0)
+ return 0;
+
+ pidfile_path = strdup(path);
+ if (pidfile_path == NULL)
return -1;
- }
- if ((f = fopen(pidfile_path, "w")) == NULL) {
+ if ((f = fopen(path, "w")) == NULL) {
free(pidfile_path);
pidfile_path = NULL;
- free(pidfile_basename);
- pidfile_basename = NULL;
return -1;
}
+ pidfile_pid = getpid();
+
(void) fprintf(f, "%d\n", pidfile_pid);
(void) fclose(f);
+
return 0;
}
-static void
-pidfile_cleanup(void)
+int
+pidfile(const char *path)
{
- /* Only remove the pidfile if it was created by this process. */
- if ((pidfile_path != NULL) && (pidfile_pid == getpid()))
- (void) unlink(pidfile_path);
+
+ if (path == NULL || strchr(path, '/') == NULL) {
+ char *default_path;
+
+ if ((default_path = generate_varrun_path(path)) == NULL)
+ return -1;
+
+ if (create_pidfile(default_path) == -1) {
+ free(default_path);
+ return -1;
+ }
+
+ free(default_path);
+ return 0;
+ } else
+ return create_pidfile(path);
}
Index: src/tests/lib/libutil/t_pidfile.c
diff -u src/tests/lib/libutil/t_pidfile.c:1.2 src/tests/lib/libutil/t_pidfile.c:1.3
--- src/tests/lib/libutil/t_pidfile.c:1.2 Wed Mar 23 09:13:54 2011
+++ src/tests/lib/libutil/t_pidfile.c Tue Mar 29 13:55:37 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: t_pidfile.c,v 1.2 2011/03/23 09:13:54 jmmv Exp $ */
+/* $NetBSD: t_pidfile.c,v 1.3 2011/03/29 13:55:37 jmmv Exp $ */
/*
* Copyright (c) 2011 The NetBSD Foundation, Inc.
@@ -46,8 +46,9 @@
#include <sys/cdefs.h>
__COPYRIGHT("@(#) Copyright (c) 2011\
The NetBSD Foundation, inc. All rights reserved.");
-__RCSID("$NetBSD: t_pidfile.c,v 1.2 2011/03/23 09:13:54 jmmv Exp $");
+__RCSID("$NetBSD: t_pidfile.c,v 1.3 2011/03/29 13:55:37 jmmv Exp $");
+#include <sys/stat.h>
#include <sys/wait.h>
#include <assert.h>
@@ -142,7 +143,7 @@
}
static void
-helper_default_basename(const char *path)
+helper_default_path(const char *path)
{
if (pidfile(NULL) == -1)
@@ -153,17 +154,17 @@
exit(EXIT_SUCCESS);
}
-ATF_TC(default_basename);
-ATF_TC_HEAD(default_basename, tc)
+ATF_TC(default_path);
+ATF_TC_HEAD(default_path, tc)
{
atf_tc_set_md_var(tc, "require.user", "root");
}
-ATF_TC_BODY(default_basename, tc)
+ATF_TC_BODY(default_path, tc)
{
char *path;
path = generate_varrun_pidfile(NULL);
- run_child(helper_default_basename, path);
+ run_child(helper_default_path, path);
ensure_deleted(path);
free(path);
}
@@ -196,6 +197,28 @@
}
static void
+helper_custom_path(const char *path)
+{
+
+ if (pidfile(path) == -1)
+ errx(EXIT_FAILURE, "Failed to create pidfile '%s'", path);
+ check_pidfile(path);
+ exit(EXIT_SUCCESS);
+}
+
+ATF_TC_WITHOUT_HEAD(custom_path);
+ATF_TC_BODY(custom_path, tc)
+{
+
+ ATF_REQUIRE(mkdir("var", 0777) != -1);
+ ATF_REQUIRE(mkdir("var/run", 0777) != -1);
+
+ run_child(helper_custom_path, "./var/run/my-pidfile.pid");
+
+ ensure_deleted("./var/run/my-pidfile.pid");
+}
+
+static void
helper_change_basenames(const char *unused_cookie)
{
char *default_path;
@@ -249,12 +272,92 @@
free(default_path);
}
+static void
+helper_change_paths(const char *unused_cookie)
+{
+
+ if (pidfile("./var/run/first.pid") == -1)
+ errx(EXIT_FAILURE, "Failed to create pidfile "
+ "'./var/run/first.pid'");
+ check_pidfile("./var/run/first.pid");
+
+ if (pidfile("./second.pid") == -1)
+ errx(EXIT_FAILURE, "Failed to create pidfile 'second.pid'");
+ ensure_deleted("./var/run/first.pid");
+ check_pidfile("./second.pid");
+
+ exit(EXIT_SUCCESS);
+}
+
+ATF_TC_WITHOUT_HEAD(change_paths);
+ATF_TC_BODY(change_paths, tc)
+{
+
+ ATF_REQUIRE(mkdir("var", 0777) != -1);
+ ATF_REQUIRE(mkdir("var/run", 0777) != -1);
+
+ run_child(helper_change_paths, NULL);
+
+ ensure_deleted("./var/run/my-pidfile.pid");
+ ensure_deleted("second.pid");
+}
+
+static void
+helper_mix(const char *unused_cookie)
+{
+ char *default_path;
+ char *custom_path;
+
+ default_path = generate_varrun_pidfile(NULL);
+ custom_path = generate_varrun_pidfile("custom-basename");
+
+ if (pidfile(NULL) == -1)
+ errx(EXIT_FAILURE, "Failed to create default pidfile");
+ check_pidfile(default_path);
+
+ if (pidfile("./second.pid") == -1)
+ errx(EXIT_FAILURE, "Failed to create pidfile 'second.pid'");
+ ensure_deleted(default_path);
+ check_pidfile("./second.pid");
+
+ if (pidfile("custom-basename") == -1)
+ errx(EXIT_FAILURE, "Failed to create pidfile 'second.pid'");
+ ensure_deleted(default_path);
+ ensure_deleted("./second.pid");
+ ensure_deleted("./custom-basename");
+ check_pidfile(custom_path);
+
+ free(custom_path);
+ free(default_path);
+ exit(EXIT_SUCCESS);
+}
+
+ATF_TC(change_mix);
+ATF_TC_HEAD(change_mix, tc)
+{
+ atf_tc_set_md_var(tc, "require.user", "root");
+}
+ATF_TC_BODY(change_mix, tc)
+{
+ char *default_path;
+
+ run_child(helper_mix, NULL);
+
+ default_path = generate_varrun_pidfile(NULL);
+ ensure_deleted(default_path);
+ ensure_deleted("second.pid");
+ free(default_path);
+}
+
ATF_TP_ADD_TCS(tp)
{
- ATF_TP_ADD_TC(tp, default_basename);
+ ATF_TP_ADD_TC(tp, default_path);
ATF_TP_ADD_TC(tp, custom_basename);
+ ATF_TP_ADD_TC(tp, custom_path);
ATF_TP_ADD_TC(tp, change_basenames);
+ ATF_TP_ADD_TC(tp, change_paths);
+ ATF_TP_ADD_TC(tp, change_mix);
return atf_no_error();
}
