Nearly complete rewrite of cgpt tool.

cgpt/cmd_create.c

+// 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.
+
+#include "cgpt.h"
+
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <uuid/uuid.h>
+
+#include "cgptlib_internal.h"
+
+static void Usage(void)
+{
+  printf("\nUsage: %s create [OPTIONS] DRIVE\n\n"
+         "Create or reset an empty GPT.\n\n"
+         "Options:\n"
+         "  -z           Zero the sectors of the GPT table and entries\n"
+         "\n", progname);
+}
+
+int cmd_create(int argc, char *argv[]) {
+  struct drive drive;
+  int zap = 0;
+  
+  int c;
+  int errorcnt = 0;
+
+  opterr = 0;                     // quiet, you
+  while ((c=getopt(argc, argv, ":hz")) != -1)
+  {
+    switch (c)
+    {
+    case 'z':
+      zap = 1;
+      break;
+
+    case 'h':
+      Usage();
+      return CGPT_OK;
+    case '?':
+      Error("unrecognized option: -%c\n", optopt);
+      errorcnt++;
+      break;
+    case ':':
+      Error("missing argument to -%c\n", optopt);
+      errorcnt++;
+      break;
+    default:
+      errorcnt++;
+      break;
+    }
+  }
+  if (errorcnt)
+  {
+    Usage();
+    return CGPT_FAILED;
+  }
+
+  if (optind >= argc) {
+    Usage();
+    return CGPT_FAILED;
+  }
+
+  if (CGPT_OK != DriveOpen(argv[optind], &drive))
+    return CGPT_FAILED;
+
+  // Erase the data
+  memset(drive.gpt.primary_header, 0,
+         drive.gpt.sector_bytes * GPT_HEADER_SECTOR);
+  memset(drive.gpt.secondary_header, 0,
+         drive.gpt.sector_bytes * GPT_HEADER_SECTOR);
+  memset(drive.gpt.primary_entries, 0,
+         drive.gpt.sector_bytes * GPT_ENTRIES_SECTORS);
+  memset(drive.gpt.secondary_entries, 0,
+         drive.gpt.sector_bytes * GPT_ENTRIES_SECTORS);
+  
+  drive.gpt.modified |= (GPT_MODIFIED_HEADER1 | GPT_MODIFIED_ENTRIES1 |
+                         GPT_MODIFIED_HEADER2 | GPT_MODIFIED_ENTRIES2);
+
+  // Initialize a blank set
+  if (!zap)
+  {
+    GptHeader *h = (GptHeader *)drive.gpt.primary_header;
+    memcpy(h->signature, GPT_HEADER_SIGNATURE, GPT_HEADER_SIGNATURE_SIZE);
+    h->revision = GPT_HEADER_REVISION;
+    h->size = sizeof(GptHeader);
+    h->my_lba = 1;
+    h->first_usable_lba = 1 + 1 + GPT_ENTRIES_SECTORS;
+    h->last_usable_lba = drive.gpt.drive_sectors - 1 - GPT_ENTRIES_SECTORS - 1;
+    uuid_generate((uint8_t *)&h->disk_uuid);
+    h->entries_lba = 2;
+    h->number_of_entries = 128;
+    h->size_of_entry = sizeof(GptEntry);
+
+    // Copy to secondary
+    RepairHeader(&drive.gpt, MASK_PRIMARY);
+
+    UpdateCrc(&drive.gpt);
+  }
+
+  // Write it all out
+  return DriveClose(&drive, 1);
+}