From 2780d0abb289bf85f463fcbb0935f3218118ae67 Mon Sep 17 00:00:00 2001
From: David Anderson <dvander@google.com>
Date: Tue, 19 Nov 2019 17:31:54 -0800
Subject: [PATCH] liblp: Allow "flashing" files on the host.

UpdatePartitionTable expects to be run on a device, which is a
reasonable assumption. However to implement lpadd (offline modification
of super images), it's useful to be able to run these methods, and
IPartitionOpener allows us to masquerade a flie as a block device.

The only catch is that we can't query partition information on the host.
Since this logic is a protection mechanism, just surround it with
an ifdef for __ANDROID__.

Bug: 144468779
Test: lpadd
Change-Id: I3c50e5677fa1dd59f2d4216038d3d4fbfb6edcc0
---
 fs_mgr/liblp/writer.cpp | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/fs_mgr/liblp/writer.cpp b/fs_mgr/liblp/writer.cpp
index 8a983adf4..bb24069aa 100644
--- a/fs_mgr/liblp/writer.cpp
+++ b/fs_mgr/liblp/writer.cpp
@@ -83,8 +83,9 @@ std::string SerializeMetadata(const LpMetadata& input) {
 
 // Perform sanity checks so we don't accidentally overwrite valid metadata
 // with potentially invalid metadata, or random partition data with metadata.
-static bool ValidateAndSerializeMetadata(const IPartitionOpener& opener, const LpMetadata& metadata,
-                                         const std::string& slot_suffix, std::string* blob) {
+static bool ValidateAndSerializeMetadata([[maybe_unused]] const IPartitionOpener& opener,
+                                         const LpMetadata& metadata, const std::string& slot_suffix,
+                                         std::string* blob) {
     const LpMetadataGeometry& geometry = metadata.geometry;
 
     *blob = SerializeMetadata(metadata);
@@ -128,6 +129,10 @@ static bool ValidateAndSerializeMetadata(const IPartitionOpener& opener, const L
                    << block_device.first_logical_sector << " for size " << block_device.size;
             return false;
         }
+
+        // When flashing on the device, check partition sizes. Don't do this on
+        // the host since there is no way to verify.
+#if defined(__ANDROID__)
         BlockDeviceInfo info;
         if (!opener.GetInfo(partition_name, &info)) {
             PERROR << partition_name << ": ioctl";
@@ -138,6 +143,7 @@ static bool ValidateAndSerializeMetadata(const IPartitionOpener& opener, const L
                    << block_device.size << ", got " << info.size << ")";
             return false;
         }
+#endif
     }
 
     // Make sure all partition entries reference valid extents.