cgpt supports dev and add/delete/modify commands.

src/platform/vboot_reference/cgptlib/cgptlib_internal.h

 /* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef VBOOT_REFERENCE_CGPTLIB_INTERNAL_H_
 #define VBOOT_REFERENCE_CGPTLIB_INTERNAL_H_
 
 #include <stdint.h>
 #include "cgptlib.h"
 
 int CheckParameters(GptData *gpt);
 uint32_t CheckHeaderSignature(GptData *gpt);
 uint32_t CheckRevision(GptData *gpt);
 uint32_t CheckSize(GptData *gpt);
 uint32_t CheckReservedFields(GptData *gpt);
 uint32_t CheckMyLba(GptData *gpt);
 uint32_t CheckSizeOfPartitionEntry(GptData *gpt);
 uint32_t CheckNumberOfEntries(GptData *gpt);
 uint32_t CheckEntriesLba(GptData *gpt);
 uint32_t CheckValidUsableLbas(GptData *gpt);
 uint32_t CheckHeaderCrc(GptData *gpt);
 uint32_t CheckEntriesCrc(GptData *gpt);
+int NonZeroGuid(const Guid *guid);
 uint32_t CheckValidEntries(GptData *gpt);
 typedef struct {
   uint64_t starting;
   uint64_t ending;
 } pair_t;
 int OverlappedEntries(GptEntry *entries, uint32_t number_of_entries);
 uint32_t CheckOverlappedPartition(GptData *gpt);
 int IsSynonymous(const GptHeader* a, const GptHeader* b);
 uint8_t RepairEntries(GptData *gpt, const uint32_t valid_entries);
 uint8_t RepairHeader(GptData *gpt, const uint32_t valid_headers);
@@ skipping 46 matching lines @@
 #define CGPT_ATTRIBUTE_MAX_TRIES (15ULL)
 #define CGPT_ATTRIBUTE_TRIES_MASK (CGPT_ATTRIBUTE_MAX_TRIES << \
                                    CGPT_ATTRIBUTE_TRIES_OFFSET)
 
 #define CGPT_ATTRIBUTE_PRIORITY_OFFSET 48
 #define CGPT_ATTRIBUTE_MAX_PRIORITY (15ULL)
 #define CGPT_ATTRIBUTE_PRIORITY_MASK (CGPT_ATTRIBUTE_MAX_PRIORITY << \
                                       CGPT_ATTRIBUTE_PRIORITY_OFFSET)
 
 #endif /* VBOOT_REFERENCE_CGPTLIB_INTERNAL_H_ */