Implementation of CgptManager C++ library and unit tests.

CgptManager exposes the cgpt commands via a C++ library so that
the post-installer for 32- to 64-bit upgrade can link directly
against a library and thus avoid any shell dependency.

The default make target will not build libcgpt-cc.a since it
requires some dependencies that are available only in chroot.
A separate follow-up checkin to the vboot_reference
ebuild will enable emerging the libcgpt-cc.a by default.

BUG=chromium-os:25374
TEST=Tested with the new unit tests for CgptManager,
     ran existing cgpt unit tests,  as well as running the
     cgpt commands manually. Built on both amd64 and x86.
     Tested that vboot_reference is also buildable outside of chroot.
     Tested that vboot_reference-firmware and vboot_reference-tests
     also build fine with these changes.
CQ-DEPEND=I99f6c321e09c2425eaa8171d78685d2d731954c8
Change-Id: I59a896255b8ea2fc8b1b2150ae7c4ff9d0769699
Reviewed-on: https://gerrit.chromium.org/gerrit/15730
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Gaurav Shah <gauravsh@chromium.org>
Commit-Ready: Jay Srinivasan <jaysri@chromium.org>
Tested-by: Jay Srinivasan <jaysri@chromium.org>

1 files changed, 50 insertions, 1 deletions

diff --git a/cgpt/cgpt_boot.c b/cgpt/cgpt_boot.c
index 15e98cfa..33c5471c 100644
--- a/cgpt/cgpt_boot.c
+++ b/cgpt/cgpt_boot.c
@@ -12,6 +12,55 @@
 #include "endian.h"
 #include "cgpt_params.h"
 
+
+int cgpt_get_boot_partition_number(CgptBootParams *params) {
+  struct drive drive;
+  int gpt_retval= 0;
+  int retval;
+
+  if (params == NULL)
+    return CGPT_FAILED;
+
+  if (CGPT_OK != DriveOpen(params->drive_name, &drive))
+    return CGPT_FAILED;
+
+  if (GPT_SUCCESS != (gpt_retval = GptSanityCheck(&drive.gpt))) {
+    Error("GptSanityCheck() returned %d: %s\n",
+          gpt_retval, GptError(gpt_retval));
+    retval = CGPT_FAILED;
+    goto done;
+  }
+
+  if (CGPT_OK != ReadPMBR(&drive)) {
+    Error("Unable to read PMBR\n");
+    goto done;
+  }
+
+  char buf[GUID_STRLEN];
+  GuidToStr(&drive.pmbr.boot_guid, buf, sizeof(buf));
+
+  int numEntries = GetNumberOfEntries(&drive.gpt);
+  int i;
+  for(i = 0; i < numEntries; i++) {
+      GptEntry *entry = GetEntry(&drive.gpt, ANY_VALID, i);
+
+      if (GuidEqual(&entry->unique, &drive.pmbr.boot_guid)) {
+        params->partition = i + 1;
+        retval = CGPT_OK;
+        goto done;
+      }
+  }
+
+  Error("Didn't find any boot partition\n");
+  params->partition = 0;
+  retval = CGPT_FAILED;
+
+done:
+  (void) DriveClose(&drive, 1);
+  return retval;
+}
+
+
 int cgpt_boot(CgptBootParams *params) {
   struct drive drive;
   int retval = 1;
@@ -20,7 +69,7 @@ int cgpt_boot(CgptBootParams *params) {
   if (params == NULL)
     return CGPT_FAILED;
 
-  if (CGPT_OK != DriveOpen(params->driveName, &drive))
+  if (CGPT_OK != DriveOpen(params->drive_name, &drive))
     return CGPT_FAILED;
 
   if (CGPT_OK != ReadPMBR(&drive)) {