Merge "allow adb to remount symlink mount points" into pie-gsi

#include <string>

#include <android-base/file.h>

#include <android-base/properties.h>

#include "adb.h"

#include "adb_utils.h"

#include "fs_mgr.h"

using android::base::Realpath;

// Returns the device used to mount a directory in /proc/mounts.

static std::string find_proc_mount(const char* dir) {

    std::unique_ptr<FILE, int(*)(FILE*)> fp(setmntent("/proc/mounts", "r"), endmntent);

        return "";

    }

    // dir might be a symlink, e.g., /product -> /system/product in GSI.

    std::string canonical_path;

    if (!Realpath(dir, &canonical_path)) {

        PLOG(ERROR) << "Realpath failed: " << dir;

    }

    mntent* e;

    while ((e = getmntent(fp.get())) != nullptr) {

        if (strcmp(dir, e->mnt_dir) == 0) {

        if (canonical_path == e->mnt_dir) {

            return e->mnt_fsname;

        }

    }