[gPXE-devel] [gPXE] PATCH: Allow "dhcp" command to iterate over multiple interfaces like autoboot()

[Lars Kellogg-Stedman]

> Please use gPXE coding style, see net/netdevice.c for examples.
> [...]

Stefan,

I've reworked the code a little bit, trying to take your suggestions
into account.  I've also removed the "-c" option because it resulted
in simpler code.  You can see the diffs here:

  http://github.com/larsks/gpxe/compare/master...lars

And the patch follows:

diff --git a/src/hci/commands/dhcp_cmd.c b/src/hci/commands/dhcp_cmd.c
index 96aac8d..593cbcb 100644
--- a/src/hci/commands/dhcp_cmd.c
+++ b/src/hci/commands/dhcp_cmd.c
@@ -31,6 +31,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #include <gpxe/in.h>
 #include <gpxe/command.h>
 #include <usr/dhcpmgmt.h>
+#include <usr/ifmgmt.h>

 /** @file
  *
@@ -45,10 +46,76 @@ FILE_LICENCE ( GPL2_OR_LATER );
  */
 static void dhcp_syntax ( char **argv ) {
 	printf ( "Usage:\n"
-		 "  %s <interface>\n"
+		 "  %s <interface> [<interface> ...]\n"
+		 "  %s any\n"
 		 "\n"
 		 "Configure a network interface using DHCP\n",
-		 argv[0] );
+		 argv[0], argv[0] );
+}
+
+/**
+ * Attempt to configure a device with dhcp.
+ *
+ * @netdev		Device to configure.
+ */
+static int dhcp_one_device ( struct net_device *netdev ) {
+	int rc;
+
+	/* Perform DHCP */
+	if ( ( rc = dhcp ( netdev ) ) != 0 ) {
+		/* close the device on error to avoid out-of-memory
+		 * condition. */
+		netdev_close( netdev );
+
+		printf ( "Could not configure %s: %s\n", netdev->name,
+				strerror ( rc ) );
+		return 1;
+	}
+
+	return 0;
+}
+
+/**
+ * Call dhcp_one_device() for each name in argv.
+ *
+ * @argc		Number of devices
+ * @argv		List of device names
+ */
+static int dhcp_each_device_name ( int argc, char *argv[] ) {
+	int i;
+	char *netdev_name;
+	struct net_device *netdev;
+
+	for ( i=0; i<argc; i++ ) {
+		netdev_name = argv[i];
+		netdev = find_netdev( netdev_name );
+
+		if ( ! netdev ) {
+			printf ( "No such interface: %s\n", netdev_name );
+			continue;
+		}
+
+		if ( dhcp_one_device ( netdev ) == 0 )
+			return 0;
+	}
+
+	printf( "Could not configure any interface.\n" );
+	return 1;
+}
+
+/**
+ * Call dhcp_one_device() for each device in net_devices.
+ */
+static int dhcp_each_device ( void ) {
+	struct net_device *netdev;
+
+	for_each_netdev ( netdev ) {
+		if ( dhcp_one_device ( netdev ) == 0 )
+			return 0;
+	}
+
+	printf( "Could not configure any interface.\n" );
+	return 1;
 }

 /**
@@ -63,10 +130,7 @@ static int dhcp_exec ( int argc, char **argv ) {
 		{ "help", 0, NULL, 'h' },
 		{ NULL, 0, NULL, 0 },
 	};
-	const char *netdev_txt;
-	struct net_device *netdev;
 	int c;
-	int rc;

 	/* Parse options */
 	while ( ( c = getopt_long ( argc, argv, "h", longopts, NULL ) ) >= 0 ){
@@ -81,27 +145,15 @@ static int dhcp_exec ( int argc, char **argv ) {
 	}

 	/* Need exactly one interface name remaining after the options */
-	if ( optind != ( argc - 1 ) ) {
+	if ( ( argc - optind ) < 1 ) {
 		dhcp_syntax ( argv );
 		return 1;
 	}
-	netdev_txt = argv[optind];
-
-	/* Parse arguments */
-	netdev = find_netdev ( netdev_txt );
-	if ( ! netdev ) {
-		printf ( "No such interface: %s\n", netdev_txt );
-		return 1;
-	}

-	/* Perform DHCP */
-	if ( ( rc = dhcp ( netdev ) ) != 0 ) {
-		printf ( "Could not configure %s: %s\n", netdev->name,
-			 strerror ( rc ) );
-		return 1;
-	}
+	if ( strcmp( argv[optind], "any" ) == 0 )
+		return dhcp_each_device();

-	return 0;
+	return dhcp_each_device_name ( argc-optind, argv+optind );
 }

 /**