Add resizefs utility

Change-Id: I5f503cf07216df64dcc33081f24cd083d003e581
Reviewed-on: https://review.haiku-os.org/c/haiku/+/943
Reviewed-by: Jérôme Duval <[email protected]>
Reviewed-by: Axel Dörfler <[email protected]>
Reviewed-by: Adrien Destugues <[email protected]>

src/bin/Jamfile

@@ -128,6 +128,7 @@ StdBinCommands
 # standard commands that need libbe.so, libsupc++.so, and libshared.a
 StdBinCommands
 	ramdisk.cpp
+	resizefs.cpp
 	: shared be [ TargetLibsupc++ ] : $(haiku-utils_rsrc) ;
 
 # standard commands that need libbe.so, libbnetapi.so, libsupc++.so

src/bin/resizefs.cpp

@@ -0,0 +1,128 @@
+/*
+ * Copyright 2012, Andreas Henriksson, [email protected].
+ * Copyright 2008, Axel Dörfler, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include <stdio.h>
+
+#include <DiskDevice.h>
+#include <DiskDeviceRoster.h>
+#include <DiskSystem.h>
+#include <StringForSize.h>
+
+
+extern "C" const char* __progname;
+static const char* kProgramName = __progname;
+
+
+int
+main(int argc, char** argv)
+{
+	if (argc != 3) {
+		fprintf(stderr, "Usage: %s <device> <size>\n",
+			"Resize volume on <device> to new size <size> (in bytes, suffixes "
+			"'k', 'm', 'g', 't' are interpreted as KiB, Mib, GiB, TiB).\n"
+			kProgramName);
+		return 1;
+	}
+
+	int64 size = parse_size(argv[2]);
+	if (size <= 0) {
+		fprintf(stderr, "%s: The new size \"%s\" is not a number\n",
+			kProgramName, argv[2]);
+		return 1;
+	}
+
+	BDiskDeviceRoster roster;
+	BPartition* partition;
+	BDiskDevice device;
+
+	status_t status = roster.GetPartitionForPath(argv[1], &device,
+		&partition);
+	if (status != B_OK) {
+		if (strncmp(argv[1], "/dev", 4)) {
+			// try mounted volume
+			status = roster.FindPartitionByMountPoint(argv[1], &device,
+				&partition) ? B_OK : B_BAD_VALUE;
+		}
+
+		// TODO: try to register file device
+
+		if (status != B_OK) {
+			fprintf(stderr, "%s: Failed to get disk device for path \"%s\": "
+				"%s\n", kProgramName, argv[1], strerror(status));
+			return 1;
+		}
+	}
+
+	// Prepare the device for modifications
+
+	status = device.PrepareModifications();
+	if (status != B_OK) {
+		fprintf(stderr, "%s: Could not prepare the device for modifications: "
+			"%s\n", kProgramName, strerror(status));
+		return false;
+	}
+
+	// Check if the partition supports resizing
+
+	bool canResizeWhileMounted;
+	bool canResize = partition->CanResize(NULL, &canResizeWhileMounted);
+
+	if (!canResize && !canResizeWhileMounted) {
+		fprintf(stderr, "%s: The disk system does not support resizing.\n",
+			kProgramName);
+		return 1;
+	}
+
+	if (partition->IsMounted() && !canResizeWhileMounted) {
+		fprintf(stderr, "%s: The disk system does not support resizing a "
+			"mounted volume.\n", kProgramName);
+		return 1;
+	}
+	if (!partition->IsMounted() && !canResize) {
+		fprintf(stderr, "%s: The disk system does not support resizing a "
+			"volume that is not mounted.\n", kProgramName);
+		return 1;
+	}
+
+	// Validate the requested size
+
+	off_t validatedSize = size;
+	status = partition->ValidateResize(&validatedSize);
+	if (status != B_OK) {
+		fprintf(stderr, "%s: Failed to validate the size: %s\n", kProgramName,
+			strerror(status));
+		return 1;
+	}
+
+	if (validatedSize != size) {
+		printf("The requested size (%" B_PRId64 " bytes) was not accepted.\n"
+			"Resize to %" B_PRId64 " bytes instead? (y/N): ", size,
+			(int64)validatedSize);
+
+		int c = getchar();
+		if (c != 'y')
+			return 0;
+	}
+
+	// Resize the volume
+
+	status = partition->Resize(validatedSize);
+	if (status != B_OK) {
+		fprintf(stderr, "%s: Resizing failed: %s\n", kProgramName,
+			strerror(status));
+		return 1;
+	}
+
+	status = device.CommitModifications();
+	if (status != B_OK) {
+		fprintf(stderr, "%s: Failed to commit modifications: %s\n",
+			kProgramName, strerror(status));
+		return 1;
+	}
+
+	return 0;
+}