Added execv() and system().

1 files changed, 139 insertions, 0 deletions

diff --git a/src/core/exec.c b/src/core/exec.c
new file mode 100644
index 00000000..a0f0b527
--- /dev/null
+++ b/src/core/exec.c
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <errno.h>
+#include <assert.h>
+#include <vsprintf.h>
+#include <gpxe/tables.h>
+#include <gpxe/command.h>
+
+/** @file
+ *
+ * Command execution
+ *
+ */
+
+static struct command commands[0] __table_start ( commands );
+static struct command commands_end[0] __table_end ( commands );
+
+/**
+ * Execute command
+ *
+ * @v command		Command name
+ * @v argv		Argument list
+ * @ret rc		Command exit status
+ *
+ * Execute the named command.  Unlike a traditional POSIX execv(),
+ * this function returns the exit status of the command.
+ */
+int execv ( const char *command, char * const argv[] ) {
+	struct command *cmd;
+	int argc = 0;
+
+	assert ( argv[0] != NULL );
+
+	/* Count number of arguments */
+	do {
+		argc++;
+	} while ( argv[argc] != NULL );
+
+	/* Reset getopt() library ready for use by the command.  This
+	 * is an artefact of the POSIX getopt() API within the context
+	 * of Etherboot; see the documentation for reset_getopt() for
+	 * details.
+	 */
+	reset_getopt();
+
+	/* Hand off to command implementation */
+	for ( cmd = commands ; cmd < commands_end ; cmd++ ) {
+		if ( strcmp ( command, cmd->name ) == 0 )
+			return cmd->exec ( argc, ( char ** ) argv );
+	}
+
+	printf ( "%s: command not found\n", command );
+	return -ENOEXEC;
+}
+
+/**
+ * Split command line into argv array
+ *
+ * @v args		Command line
+ * @v argv		Argument array to populate, or NULL
+ * @ret argc		Argument count
+ *
+ * Splits the command line into whitespace-delimited arguments.  If @c
+ * argv is non-NULL, any whitespace in the command line will be
+ * replaced with NULs.
+ */
+static int split_args ( char *args, char * argv[] ) {
+	int argc = 0;
+
+	while ( 1 ) {
+		/* Skip over any whitespace / convert to NUL */
+		while ( *args == ' ' ) {
+			if ( argv )
+				*args = '\0';
+			args++;
+		}
+		/* Check for end of line */
+		if ( ! *args )
+			break;
+		/* We have found the start of the next argument */
+		if ( argv )
+			argv[argc] = args;
+		argc++;
+		/* Skip to start of next whitespace, if any */
+		while ( *args && ( *args != ' ' ) ) {
+			args++;
+		}
+	}
+	return argc;
+}
+
+/**
+ * Execute command line
+ *
+ * @v command		Command line
+ * @ret rc		Command exit status
+ *
+ * Execute the named command and arguments.
+ */
+int system ( const char *command ) {
+	char *args = strdup ( command );
+	int argc;
+	
+	if ( ! args )
+		return -ENOMEM;
+
+	/* Count arguments */
+	argc = split_args ( args, NULL );
+
+	/* Create argv array and execute command */
+	{
+		char * argv[argc + 1];
+		
+		split_args ( args, argv );
+		argv[argc] = NULL;
+		return execv ( argv[0], argv );
+	}
+}