[master] Restores use of env vars for lease and pid files

    Merges in rt46859.

2 files changed, 65 insertions, 74 deletions

diff --git a/server/dhcpd.c b/server/dhcpd.c
index ea62d1a0..dfc617d0 100644
--- a/server/dhcpd.c
+++ b/server/dhcpd.c
@@ -271,9 +271,9 @@ main(int argc, char **argv) {
 	struct parse *parse;
 	int lose;
 #endif
-	int no_dhcpd_conf = 0;
-	int no_dhcpd_db = 0;
-	int no_dhcpd_pid = 0;
+	int have_dhcpd_conf = 0;
+	int have_dhcpd_db = 0;
+	int have_dhcpd_pid = 0;
 #ifdef DHCPv6
 	int local_family_set = 0;
 #ifdef DHCP4o6
@@ -464,17 +464,17 @@ main(int argc, char **argv) {
 			if (++i == argc)
 				usage(use_noarg, argv[i-1]);
 			path_dhcpd_conf = argv [i];
-			no_dhcpd_conf = 1;
+			have_dhcpd_conf = 1;
 		} else if (!strcmp (argv [i], "-lf")) {
 			if (++i == argc)
 				usage(use_noarg, argv[i-1]);
 			path_dhcpd_db = argv [i];
-			no_dhcpd_db = 1;
+			have_dhcpd_db = 1;
 		} else if (!strcmp (argv [i], "-pf")) {
 			if (++i == argc)
 				usage(use_noarg, argv[i-1]);
 			path_dhcpd_pid = argv [i];
-			no_dhcpd_pid = 1;
+			have_dhcpd_pid = 1;
 		} else if (!strcmp(argv[i], "--no-pid")) {
 			no_pid_file = ISC_TRUE;
                 } else if (!strcmp (argv [i], "-t")) {
@@ -570,42 +570,43 @@ main(int argc, char **argv) {
 	}
 #endif /* DHCPv6 && DHCP4o6 */
 
-	if (!no_dhcpd_conf && (s = getenv ("PATH_DHCPD_CONF"))) {
+	if (!have_dhcpd_conf && (s = getenv ("PATH_DHCPD_CONF"))) {
 		path_dhcpd_conf = s;
 	}
 
 #ifdef DHCPv6
         if (local_family == AF_INET6) {
                 /* DHCPv6: override DHCPv4 lease and pid filenames */
-	        if (!no_dhcpd_db) {
+	        if (!have_dhcpd_db) {
                         if ((s = getenv ("PATH_DHCPD6_DB")))
 		                path_dhcpd_db = s;
                         else
 		                path_dhcpd_db = _PATH_DHCPD6_DB;
 	        }
-	        if (!no_dhcpd_pid) {
+	        if (!have_dhcpd_pid) {
                         if ((s = getenv ("PATH_DHCPD6_PID")))
 		                path_dhcpd_pid = s;
                         else
 		                path_dhcpd_pid = _PATH_DHCPD6_PID;
 	        }
         } else
-#else /* !DHCPv6 */
+#endif /* DHCPv6 */
         {
-	        if (!no_dhcpd_db && (s = getenv ("PATH_DHCPD_DB"))) {
+	        if (!have_dhcpd_db && (s = getenv ("PATH_DHCPD_DB"))) {
 		        path_dhcpd_db = s;
+			have_dhcpd_db = 1;
 	        }
-	        if (!no_dhcpd_pid && (s = getenv ("PATH_DHCPD_PID"))) {
+	        if (!have_dhcpd_pid && (s = getenv ("PATH_DHCPD_PID"))) {
 		        path_dhcpd_pid = s;
+			have_dhcpd_pid = 1;
 	        }
         }
-#endif /* DHCPv6 */
 
         /*
          * convert relative path names to absolute, for files that need
          * to be reopened after chdir() has been called
          */
-        if (path_dhcpd_db[0] != '/') {
+        if (have_dhcpd_db && path_dhcpd_db[0] != '/') {
 		const char *path = path_dhcpd_db;
                 path_dhcpd_db = realpath(path_dhcpd_db, NULL);
                 if (path_dhcpd_db == NULL)
@@ -795,7 +796,7 @@ main(int argc, char **argv) {
 
 #if defined (TRACING)
 	if (traceinfile) {
-	    if (!no_dhcpd_db) {
+	    if (!have_dhcpd_db) {
 		    log_error ("%s", "");
 		    log_error ("** You must specify a lease file with -lf.");
 		    log_error ("   Dhcpd will not overwrite your default");
diff --git a/server/dhcpd.conf.5 b/server/dhcpd.conf.5
index 1ba4009f..b32915d4 100644
--- a/server/dhcpd.conf.5
+++ b/server/dhcpd.conf.5
@@ -2633,31 +2633,16 @@ statement
 .B lease-file-name \fIname\fB;\fR
 .PP
 .I Name
-should be the name of the DHCP server's lease file.  By default, this
-is DBDIR/dhcpd.leases.  This statement \fBmust\fR appear in the outer
-scope of the configuration file - if it appears in some other scope,
-it will have no effect.  Furthermore, it has no effect if overridden
-by the
-.B -lf
-flag or the
-.B PATH_DHCPD_DB
-environment variable.
-.RE
-.PP
-The
-.I limit-addrs-per-ia
-statement
-.RS 0.25i
+Where \fIname\fR is the name of the DHCP server's lease file. By default,
+this is DBDIR/dhcpd.leases.  This statement \fBmust\fR appear in the outer
+scope of the configuration file - if it appears in some other scope, it will
+have no effect.  The value must be the absolute path of the file to use.
+The order of precedence the server uses for the lease file name
+is:
 .PP
-.B limit-addrs-per-ia \fInumber\fB;\fR
-.PP
-By default, the DHCPv6 server will limit clients to one IAADDR per IA
-option, meaning one address.  If you wish to permit clients to hang onto
-multiple addresses at a time, configure a larger \fInumber\fR here.
-.PP
-Note that there is no present method to configure the server to forcibly
-configure the client with one IP address per each subnet on a shared network.
-This is left to future work.
+    1. \fBlease-file-name\fR configuration file statement.
+    2. \fB-lf\fR command line flag.
+    3. \fBPATH_DHCPD_DB\fR environment variable.
 .RE
 .PP
 The
@@ -2667,21 +2652,16 @@ statement
 .PP
 .B dhcpv6-lease-file-name \fIname\fB;\fR
 .PP
-.I Name
-is the name of the lease file to use if and only if the server is running
-in DHCPv6 mode.  By default, this is DBDIR/dhcpd6.leases.  This statement,
-like
-.I lease-file-name,
-\fBmust\fR appear in the outer scope of the configuration file.  It
-has no effect if overridden by the
-.B -lf
-flag or the
-.B PATH_DHCPD6_DB
-environment variable.  If
-.I dhcpv6-lease-file-name
-is not specified, but
-.I lease-file-name
-is, the latter value will be used.
+Where \fIname\fR is the name of the DHCP server's lease file when the server
+is running DHCPv6. By default, this is DBDIR/dhcpd6.leases. This statement
+\fBmust\fR appear in the outer scope of the configuration file - if it appears
+in some other scope, it will have no effect.  The value must be the absolute
+path of the file to use.  The order of precedence the server uses
+for the lease file name is:
+.PP
+    1. \fBdhcpv6-lease-file-name\fR configuration file statement.
+    2. \fB-lf\fR command line flag.
+    3. \fBPATH_DHCPD6_DB\fR environment variable.
 .RE
 .PP
 The
@@ -2705,6 +2685,22 @@ automatically reads the values in either format.
 .RE
 .PP
 The
+.I limit-addrs-per-ia
+statement
+.RS 0.25i
+.PP
+.B limit-addrs-per-ia \fInumber\fB;\fR
+.PP
+By default, the DHCPv6 server will limit clients to one IAADDR per IA
+option, meaning one address.  If you wish to permit clients to hang onto
+multiple addresses at a time, configure a larger \fInumber\fR here.
+.PP
+Note that there is no present method to configure the server to forcibly
+configure the client with one IP address per each subnet on a shared network.
+This is left to future work.
+.RE
+.PP
+The
 .I local-port
 statement
 .RS 0.25i
@@ -2970,14 +2966,13 @@ statement
 .I Name
 should be the name of the DHCP server's process ID file.  This is the
 file in which the DHCP server's process ID is stored when the server
-starts.  By default, this is RUNDIR/dhcpd.pid.  Like the
-.I lease-file-name
-statement, this statement must appear in the outer scope
-of the configuration file.  It has no effect if overridden by the
-.B -pf
-flag or the
-.B PATH_DHCPD_PID
-environment variable.
+starts.  By default, this is RUNDIR/dhcpd.pid.  Like the \fIlease-file-name\fR
+statement, this statement must appear in the outer scope of the configuration
+file. The order of precedence used by the server is:
+.PP
+    1. \fBpid-file-name\fR configuration file statement.
+    2. \fB-lf\fR command line flag.
+    3. \fBPATH_DHCPD_PID\fR environment variable.
 .PP
 The
 .I dhcpv6-pid-file-name
@@ -2989,18 +2984,13 @@ statement
 .I Name
 is the name of the pid file to use if and only if the server is running
 in DHCPv6 mode.  By default, this is DBDIR/dhcpd6.pid.  This statement,
-like
-.I pid-file-name,
-\fBmust\fR appear in the outer scope of the configuration file.  It
-has no effect if overridden by the
-.B -pf
-flag or the
-.B PATH_DHCPD6_PID
-environment variable.  If
-.I dhcpv6-pid-file-name
-is not specified, but
-.I pid-file-name
-is, the latter value will be used.
+like \fIpid-file-name\fr, \fBmust\fR appear in the outer scope of the
+configuration file.  The order of precedence used by the server is:
+.PP
+    1. \fBdhcpv6-pid-file-name\fR configuration file statement.
+    2. \fB-lf\fR command line flag.
+    3. \fBPATH_DHCPD6_PID\fR environment variable.
+.PP
 .RE
 .PP
 The