Nearly complete rewrite of cgpt tool.

cgpt/cmd_boot.c

Index: cgpt/cmd_boot.c
diff --git a/cgpt/cmd_boot.c b/cgpt/cmd_boot.c
new file mode 100644
index 0000000000000000000000000000000000000000..784684a24d404188e880ef6480a15f42dacb2f30
--- /dev/null
+++ b/cgpt/cmd_boot.c
@@ -0,0 +1,167 @@
+// 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 <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <uuid/uuid.h>
+
+#include "cgptlib_internal.h"
+#include "endian.h"
+
+static void Usage(void)
+{
+  printf("\nUsage: %s boot [OPTIONS] DRIVE\n\n"
+         "Edit the PMBR sector for legacy BIOSes\n\n"
+         "Options:\n"
+         "  -i NUM       Set bootable partition\n"
+         "  -b FILE      Install bootloader code in the PMBR\n"
+         "  -p           Create legacy PMBR partition table\n"
+         "\n"
+         "With no options, it will just print the PMBR boot guid\n"
+         "\n", progname);
+}
+
+
+int cmd_boot(int argc, char *argv[]) {
+  struct drive drive;
+  int partition = 0;
+  char *bootfile = 0;
+  int create_pmbr = 0;
+  int retval = 1;
+  int gpt_retval;
+  
+  int c;
+  int errorcnt = 0;
+  char *e = 0;
+
+  opterr = 0;                     // quiet, you
+  while ((c=getopt(argc, argv, ":hi:b:p")) != -1)
+  {
+    switch (c)
+    {
+    case 'i':
+      partition = (uint32_t)strtoul(optarg, &e, 0);
+      if (!*optarg || (e && *e))
+      {
+        Error("invalid argument to -%c: \"%s\"\n", c, optarg);
+        errorcnt++;
+      }
+      break;
+    case 'b':
+      bootfile = optarg;
+      break;
+    case 'p':
+      create_pmbr = 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) {
+    Error("missing drive argument\n");
+    return CGPT_FAILED;
+  }
+
+  if (CGPT_OK != DriveOpen(argv[optind], &drive))
+    return CGPT_FAILED;
+
+  if (CGPT_OK != ReadPMBR(&drive)) {
+    Error("Unable to read PMBR\n");
+    goto done;
+  }
+    
+  if (create_pmbr) {
+    drive.pmbr.magic[0] = 0x1d;
+    drive.pmbr.magic[1] = 0x9a;
+    drive.pmbr.sig[0] = 0x55;
+    drive.pmbr.sig[1] = 0xaa;
+    memset(&drive.pmbr.part, 0, sizeof(drive.pmbr.part));
+    drive.pmbr.part[0].f_head = 0x00;
+    drive.pmbr.part[0].f_sect = 0x02;
+    drive.pmbr.part[0].f_cyl = 0x00;
+    drive.pmbr.part[0].type = 0xee;
+    drive.pmbr.part[0].l_head = 0xff;
+    drive.pmbr.part[0].l_sect = 0xff;
+    drive.pmbr.part[0].l_cyl = 0xff;
+    drive.pmbr.part[0].f_lba = htole32(1);
+    uint32_t max = 0xffffffff;
+    if (drive.gpt.drive_sectors < 0xffffffff)
+      max = drive.gpt.drive_sectors - 1;
+    drive.pmbr.part[0].num_sect = htole32(max);
+  }
+
+  if (partition) {
+    if (GPT_SUCCESS != (gpt_retval = GptSanityCheck(&drive.gpt))) {
+      Error("GptSanityCheck() returned %d: %s\n",
+            gpt_retval, GptError(gpt_retval));
+      goto done;
+    }
+
+    if (partition > GetNumberOfEntries(&drive.gpt)) {
+      Error("invalid partition number: %d\n", partition);
+      goto done;
+    }
+
+    int index = partition - 1;
+    GptEntry *entry = GetEntry(&drive.gpt, PRIMARY, index);
+    memcpy(&drive.pmbr.boot_guid, &entry->unique, sizeof(Guid));
+  }
+
+  if (bootfile) {
+    int fd = open(bootfile, O_RDONLY);
+    if (fd < 0) {
+      Error("Can't read %s: %s\n", bootfile, strerror(errno));
+      goto done;
+    }
+
+    int n = read(fd, drive.pmbr.bootcode, sizeof(drive.pmbr.bootcode));
+    if (n < 1) {
+      Error("problem reading %s: %s\n", bootfile, strerror(errno));
+      close(fd);
+      goto done;
+    }
+
+    close(fd);
+  }
+      
+  char buf[256];
+  GuidToStr(&drive.pmbr.boot_guid, buf);
+  printf("%s\n", buf);
+
+  // Write it all out
+  if (CGPT_OK == WritePMBR(&drive))
+    retval = 0;
+
+done:
+  (void) DriveClose(&drive, 1);
+  return retval;
+}