1 files changed, 103 insertions, 0 deletions
diff --git a/libmisc/shell.c b/libmisc/shell.c
new file mode 100644
index 0000000..92bfc2b
--- /dev/null
+++ b/libmisc/shell.c
@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 1989 - 1991, Julianne Frances Haugh
+ * Copyright (c) 1996 - 1998, Marek Michałkiewicz
+ * Copyright (c) 2003 - 2006, Tomasz Kłoczko
+ * Copyright (c) 2009       , Nicolas François
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the copyright holders or contributors may not be used to
+ *    endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <config.h>
+
+#ident "$Id$"
+
+#include <stdio.h>
+#include <errno.h>
+#include "prototypes.h"
+#include "defines.h"
+extern char **newenvp;
+extern size_t newenvc;
+
+/*
+ * shell - execute the named program
+ *
+ *	shell begins by trying to figure out what argv[0] is going to
+ *	be for the named process.  The user may pass in that argument,
+ *	or it will be the last pathname component of the file with a
+ *	'-' prepended.
+ *	Then, it executes the named file.
+ */
+
+int shell (const char *file, /*@null@*/const char *arg, char *const envp[])
+{
+	char arg0[1024];
+	int err;
+
+	if (file == (char *) 0) {
+		errno = EINVAL;
+		return errno;
+	}
+
+	/*
+	 * The argv[0]'th entry is usually the path name, but
+	 * for various reasons the invoker may want to override
+	 * that.  So, we determine the 0'th entry only if they
+	 * don't want to tell us what it is themselves.
+	 */
+	if (arg == (char *) 0) {
+		(void) snprintf (arg0, sizeof arg0, "-%s", Basename ((char *) file));
+		arg0[sizeof arg0 - 1] = '\0';
+		arg = arg0;
+	}
+
+	/*
+	 * First we try the direct approach.  The system should be
+	 * able to figure out what we are up to without too much
+	 * grief.
+	 */
+	(void) execle (file, arg, (char *) 0, envp);
+	err = errno;
+
+	if (access (file, R_OK|X_OK) == 0) {
+		/*
+		 * Assume this is a shell script (with no shebang).
+		 * Interpret it with /bin/sh
+		 */
+		(void) execle (SHELL, "sh", "-", file, (char *)0, envp);
+		err = errno;
+	}
+
+	/*
+	 * Obviously something is really wrong - I can't figure out
+	 * how to execute this stupid shell, so I might as well give
+	 * up in disgust ...
+	 */
+	(void) snprintf (arg0, sizeof arg0, _("Cannot execute %s"), file);
+	errno = err;
+	perror (arg0);
+	return err;
+}
+