Add android::fs_mgr namespace for new Fstab code

Also add libfstab dependencies where needed.  Previously the
`typedef struct FstabEntry Volume;` line served to both define a
`struct FstabEntry` as well as alias Volume to it.  With the new
namespace for android::fs_mgr::FstabEntry, `struct FstabEntry` isn't
compatible anymore, so we need to alias Volume to the real
android::fs_mgr::FstabEntry.

In doing so, we need to include <fstab/fstab.h> and this requires
libfstab as a library, which a few modules did not have before.

Test: treehugger
Change-Id: I655209a0efb304b3e0568db0748bd5cf7cecbdb7

Android.bp

@@ -45,6 +45,7 @@ cc_library {
     static_libs: [
         "libminui",
         "libotautil",
+        "libfstab",
     ],
 
     shared_libs: [
@@ -157,6 +158,7 @@ cc_defaults {
         "libhealthhalutils",
         "libvintf_recovery",
         "libvintf",
+        "libfstab",
     ],
 }
 
@@ -260,6 +262,7 @@ cc_binary {
 
     static_libs: [
         "libotautil",
+        "libfstab",
     ],
 
     init_rc: [
@@ -287,6 +290,7 @@ cc_binary {
 
     static_libs: [
         "libotautil",
+        "libfstab",
     ],
 
     init_rc: [

bootloader_message/bootloader_message.cpp

@@ -29,6 +29,9 @@
 #include <android-base/unique_fd.h>
 #include <fstab/fstab.h>
 
+using android::fs_mgr::Fstab;
+using android::fs_mgr::ReadDefaultFstab;
+
 static std::string get_misc_blk_device(std::string* err) {
   Fstab fstab;
   if (!ReadDefaultFstab(&fstab)) {

roots.cpp

@@ -45,6 +45,10 @@
 #include "otautil/mounts.h"
 #include "otautil/sysutil.h"
 
+using android::fs_mgr::Fstab;
+using android::fs_mgr::FstabEntry;
+using android::fs_mgr::ReadDefaultFstab;
+
 static Fstab fstab;
 
 extern struct selabel_handle* sehandle;
@@ -69,10 +73,7 @@ void load_volume_table() {
 }
 
 Volume* volume_for_mount_point(const std::string& mount_point) {
-  auto it = std::find_if(fstab.begin(), fstab.end(), [&mount_point](const auto& entry) {
-    return entry.mount_point == mount_point;
-  });
-  return it == fstab.end() ? nullptr : &*it;
+  return android::fs_mgr::GetEntryForMountPoint(&fstab, mount_point);
 }
 
 // Mount the volume specified by path at the given mount_point.

roots.h

@@ -19,7 +19,9 @@
 
 #include <string>
 
-typedef struct FstabEntry Volume;
+#include <fstab/fstab.h>
+
+using Volume = android::fs_mgr::FstabEntry;
 
 // Load and parse volume data from /etc/recovery.fstab.
 void load_volume_table();

uncrypt/uncrypt.cpp

@@ -119,6 +119,9 @@
 
 #include "otautil/error_code.h"
 
+using android::fs_mgr::Fstab;
+using android::fs_mgr::ReadDefaultFstab;
+
 static constexpr int WINDOW_SIZE = 5;
 static constexpr int FIBMAP_RETRY_LIMIT = 3;