Implement a remove command. The remove command iterates the GPT

partitions and removes any that matches the pre-conditions. The
options are the same for the add command and are used to select
the partitions to remove.
Currently the remove command without any options deletes all GPT
partitions. This is rather harmful and will need anti-footshooting
measures.

sbin/gpt/Makefile

@@ -1,7 +1,8 @@
 # $FreeBSD$
 
 PROG=	gpt
-SRCS=	add.c create.c destroy.c gpt.c map.c migrate.c recover.c show.c
+SRCS=	add.c create.c destroy.c gpt.c map.c migrate.c recover.c remove.c \
+	show.c
 WARNS?=	4
 MAN=	gpt.8
 

sbin/gpt/gpt.c

@@ -415,11 +415,11 @@ static struct {
 } cmdsw[] = {
 	{ cmd_add, "add" },
 	{ cmd_create, "create" },
-	{ NULL, "delete" },
 	{ cmd_destroy, "destroy" },
 	{ NULL, "help" },
 	{ cmd_migrate, "migrate" },
 	{ cmd_recover, "recover" },
+	{ cmd_remove, "remove" },
 	{ NULL, "rename" },
 	{ cmd_show, "show" },
 	{ NULL, "verify" },

sbin/gpt/gpt.h

@@ -69,6 +69,7 @@ int	cmd_create(int, char *[]);
 int	cmd_destroy(int, char *[]);
 int	cmd_migrate(int, char *[]);
 int	cmd_recover(int, char *[]);
+int	cmd_remove(int, char *[]);
 int	cmd_show(int, char *[]);
 
 #endif /* _GPT_H_ */

sbin/gpt/map.h

@@ -44,7 +44,7 @@ typedef struct map {
 #define	MAP_TYPE_SEC_GPT_TBL	6
 #define	MAP_TYPE_GPT_PART	7
 #define	MAP_TYPE_PMBR		8
-	int	map_index;
+	unsigned int map_index;
 	void 	*map_data;
 } map_t;
 

sbin/gpt/remove.c

@@ -0,0 +1,212 @@
+/*
+ * Copyright (c) 2004 Marcel Moolenaar
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/disklabel.h>
+#include <sys/gpt.h>
+
+#include <err.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <uuid.h>
+
+#include "map.h"
+#include "gpt.h"
+
+static uuid_t type;
+static off_t block, size;
+static unsigned int entry;
+
+static void
+usage_remove(void)
+{
+
+	fprintf(stderr,
+	    "usage: %s [-b lba] [-i index] [-s lba] [-t uuid] device\n",
+	    getprogname());
+	exit(1);
+}
+
+static void
+rem(int fd)
+{
+	map_t *gpt, *tpg;
+	map_t *tbl, *lbt;
+	map_t *m;
+	struct gpt_hdr *hdr;
+	struct gpt_ent *ent;
+	unsigned int i, removed;
+
+	gpt = map_find(MAP_TYPE_PRI_GPT_HDR);
+	if (gpt == NULL) {
+		warnx("%s: error: no primary GPT header; run create or recover",
+		    device_name);
+		return;
+	}
+
+	tpg = map_find(MAP_TYPE_SEC_GPT_HDR);
+	if (tpg == NULL) {
+		warnx("%s: error: no secondary GPT header; run recover",
+		    device_name);
+		return;
+	}
+
+	tbl = map_find(MAP_TYPE_PRI_GPT_TBL);
+	lbt = map_find(MAP_TYPE_SEC_GPT_TBL);
+	if (tbl == NULL || lbt == NULL) {
+		warnx("%s: error: run recover -- trust me", device_name);
+		return;
+	}
+
+	removed = 0;
+
+	/* Remove all matching entries in the map. */
+	for (m = map_first(); m != NULL; m = m->map_next) {
+		if (m->map_type != MAP_TYPE_GPT_PART || m->map_index < 1)
+			continue;
+		if (entry > 0 && entry != m->map_index)
+			continue;
+		if (block > 0 && block != m->map_start)
+			continue;
+		if (size > 0 && size != m->map_size)
+			continue;
+
+		i = m->map_index - 1;
+
+		hdr = gpt->map_data;
+		ent = (void*)((char*)tbl->map_data + i * hdr->hdr_entsz);
+		if (!uuid_is_nil(&type, NULL) &&
+		    !uuid_equal(&type, &ent->ent_type, NULL))
+			continue;
+		uuid_create_nil(&ent->ent_type, NULL);
+
+		hdr->hdr_crc_table = crc32(tbl->map_data,
+		    hdr->hdr_entries * hdr->hdr_entsz);
+		hdr->hdr_crc_self = 0;
+		hdr->hdr_crc_self = crc32(hdr, hdr->hdr_size);
+
+		gpt_write(fd, gpt);
+		gpt_write(fd, tbl);
+
+		hdr = tpg->map_data;
+		ent = (void*)((char*)lbt->map_data + i * hdr->hdr_entsz);
+		uuid_create_nil(&ent->ent_type, NULL);
+
+		hdr->hdr_crc_table = crc32(lbt->map_data,
+		    hdr->hdr_entries * hdr->hdr_entsz);
+		hdr->hdr_crc_self = 0;
+		hdr->hdr_crc_self = crc32(hdr, hdr->hdr_size);
+
+		gpt_write(fd, lbt);
+		gpt_write(fd, tpg);
+
+		removed++;
+	}
+
+	warnx("%s: %d partition(s) removed", device_name, removed);
+}
+
+int
+cmd_remove(int argc, char *argv[])
+{
+	char *p;
+	int ch, fd;
+	uint32_t status;
+
+	/* Get the remove options */
+	while ((ch = getopt(argc, argv, "b:i:s:t:")) != -1) {
+		switch(ch) {
+		case 'b':
+			if (block > 0)
+				usage_remove();
+			block = strtol(optarg, &p, 10);
+			if (*p != 0 || block < 1)
+				usage_remove();
+			break;
+		case 'i':
+			if (entry > 0)
+				usage_remove();
+			entry = strtol(optarg, &p, 10);
+			if (*p != 0 || entry < 1)
+				usage_remove();
+			break;
+		case 's':
+			if (size > 0)
+				usage_remove();
+			size = strtol(optarg, &p, 10);
+			if (*p != 0 || size < 1)
+				usage_remove();
+			break;
+		case 't':
+			if (!uuid_is_nil(&type, NULL))
+				usage_remove();
+			uuid_from_string(optarg, &type, &status);
+			if (status != uuid_s_ok) {
+				if (strcmp(optarg, "efi") == 0) {
+					uuid_t efi = GPT_ENT_TYPE_EFI;
+					type = efi;
+				} else if (strcmp(optarg, "swap") == 0) {
+					uuid_t sw = GPT_ENT_TYPE_FREEBSD_SWAP;
+					type = sw;
+				} else if (strcmp(optarg, "ufs") == 0) {
+					uuid_t ufs = GPT_ENT_TYPE_FREEBSD_UFS;
+					type = ufs;
+				} else if (strcmp(optarg, "linux") == 0 ||
+				    strcmp(optarg, "windows") == 0) {
+					uuid_t m = GPT_ENT_TYPE_MS_BASIC_DATA;
+					type = m;
+				} else
+					usage_remove();
+			}
+			break;
+		default:
+			usage_remove();
+		}
+	}
+
+	if (argc == optind)
+		usage_remove();
+
+	while (optind < argc) {
+		fd = gpt_open(argv[optind++]);
+		if (fd == -1) {
+			warn("unable to open device '%s'", device_name);
+			continue;
+		}
+
+		rem(fd);
+
+		gpt_close(fd);
+	}
+
+	return (0);
+}