From 2abd0cf754fd5c2fe302656716c72cca15c68fd2 Mon Sep 17 00:00:00 2001
From: Jonas 'Sortie' Termansen <sortie@maxsi.org>
Date: Wed, 7 May 2014 14:15:52 +0200
Subject: [PATCH] Add unmount(1).

---
 doc/user-guide    |   1 +
 utils/.gitignore  |   1 +
 utils/Makefile    |   1 +
 utils/unmount.cpp | 124 ++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 127 insertions(+)
 create mode 100644 utils/unmount.cpp

diff --git a/doc/user-guide b/doc/user-guide
index 22d9c2a2..3f2d623d 100644
--- a/doc/user-guide
+++ b/doc/user-guide
@@ -200,6 +200,7 @@ Sortix comes with a number of home-made programs. Here is an overview:
 * `type` - type raw characters directly into the terminal
 * `uname` - system information
 * `uniq` - report or omit repeated lines
+* `unmount` - unmount filesystem
 * `uptime` - time since initialization
 * `wc` - count words and lines
 * `which` - find path to command
diff --git a/utils/.gitignore b/utils/.gitignore
index e5689b80..3517a8ac 100644
--- a/utils/.gitignore
+++ b/utils/.gitignore
@@ -40,6 +40,7 @@ true
 type
 uname
 uniq
+unmount
 uptime
 wc
 which
diff --git a/utils/Makefile b/utils/Makefile
index 26acda7e..8c3c2920 100644
--- a/utils/Makefile
+++ b/utils/Makefile
@@ -52,6 +52,7 @@ true \
 type \
 uname \
 uniq \
+unmount \
 uptime \
 wc \
 which \
diff --git a/utils/unmount.cpp b/utils/unmount.cpp
new file mode 100644
index 00000000..c5f1a75c
--- /dev/null
+++ b/utils/unmount.cpp
@@ -0,0 +1,124 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2014.
+
+    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 3 of the License, or (at your option)
+    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, see <http://www.gnu.org/licenses/>.
+
+    unmount.cpp
+    Unmount a filesystem.
+
+*******************************************************************************/
+
+#include <sys/mount.h>
+
+#include <errno.h>
+#include <error.h>
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static void compact_arguments(int* argc, char*** argv)
+{
+	for ( int i = 0; i < *argc; i++ )
+	{
+		while ( i < *argc && !(*argv)[i] )
+		{
+			for ( int n = i; n < *argc; n++ )
+				(*argv)[n] = (*argv)[n+1];
+			(*argc)--;
+		}
+	}
+}
+
+static void help(FILE* fp, const char* argv0)
+{
+	fprintf(fp, "Usage: %s [OPTION]... DIRECTORY...\n", argv0);
+	fprintf(fp, "Unmounts filesystems mounted at directories..\n");
+	fprintf(fp, "\n");
+	fprintf(fp, "Mandatory arguments to long options are mandatory for short options too.\n");
+	fprintf(fp, "  -f, --force   unmount even though still in use\n");
+	fprintf(fp, "  -l, --lazy    remove mountpoint but delay unmounting until no longer used");
+
+}
+
+static void version(FILE* fp, const char* argv0)
+{
+	fprintf(fp, "%s (Sortix) %s\n", argv0, VERSIONSTR);
+	fprintf(fp, "License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.\n");
+	fprintf(fp, "This is free software: you are free to change and redistribute it.\n");
+	fprintf(fp, "There is NO WARRANTY, to the extent permitted by law.\n");
+}
+
+int main(int argc, char* argv[])
+{
+	setlocale(LC_ALL, "");
+
+	bool force = false;
+	bool lazy = false;
+
+	const char* argv0 = argv[0];
+	for ( int i = 1; i < argc; i++ )
+	{
+		const char* arg = argv[i];
+		if ( arg[0] != '-' || !arg[1] )
+			continue;
+		argv[i] = NULL;
+		if ( !strcmp(arg, "--") )
+			break;
+		if ( arg[1] != '-' )
+		{
+			while ( char c = *++arg ) switch ( c )
+			{
+			case 'f': force = true; break;
+			case 'l': lazy = true; break;
+			default:
+				fprintf(stderr, "%s: unknown option -- '%c'\n", argv0, c);
+				help(stderr, argv0);
+				exit(1);
+			}
+		}
+		else if ( !strcmp(arg, "--help") )
+			help(stdout, argv0), exit(0);
+		else if ( !strcmp(arg, "--version") )
+			version(stdout, argv0), exit(0);
+		else if ( !strcmp(arg, "--force") )
+			force = true;
+		else if ( !strcmp(arg, "--lazy") )
+			lazy = true;
+		else
+		{
+			fprintf(stderr, "%s: unknown option: %s\n", argv0, arg);
+			help(stderr, argv0);
+			exit(1);
+		}
+	}
+
+	compact_arguments(&argc, &argv);
+
+	int flags = 0;
+	if ( flags & force )
+		flags |= UNMOUNT_FORCE;
+	if ( flags & lazy )
+		flags |= UNMOUNT_DETACH;
+
+	for ( int i = 1; i < argc; i++ )
+	{
+		const char* path = argv[i];
+		if ( unmount(path, flags) < 0 )
+			error(1, errno, "`%s'", path);
+	}
+
+	return 0;
+}