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Commit d6eba89f authored by Daniel Rosenberg's avatar Daniel Rosenberg
Browse files

Fix "adb remount" for when the root directory is in system.img 

When the root directory has been built into system.img, it is
mounted at /.

Change-Id: If01d12efeaa53b4ae59e801a6e9b802a9ae5882d
parent c9aeae27

adb/remount_service.cpp

+34 −2
Original line number Diff line number Diff line
@@ -33,9 +33,12 @@ 
#include "adb_io.h"

#include "adb_utils.h"

#include "cutils/properties.h"

#include "fs_mgr.h"



const std::string kFstab_Prefix = "/fstab.";



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

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

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

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

    if (!fp) {

        return "";
@@ -50,6 +53,29 @@ static std::string find_mount(const char* dir) { 
    return "";

}



// Returns the device used to mount a directory in the fstab.

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

    char propbuf[PROPERTY_VALUE_MAX];



    property_get("ro.hardware", propbuf, "");

    std::string fstab_filename = kFstab_Prefix + propbuf;

    struct fstab* fstab = fs_mgr_read_fstab(fstab_filename.c_str());

    struct fstab_rec* rec = fs_mgr_get_entry_for_mount_point(fstab, dir);

    std::string dev = rec ? std::string(rec->blk_device) : "";

    fs_mgr_free_fstab(fstab);

    return dev;

}



// The proc entry for / is full of lies, so check fstab instead.

// /proc/mounts lists rootfs and /dev/root, neither of which is what we want.

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

    if (strcmp(dir, "/") == 0) {

       return find_fstab_mount(dir);

    } else {

       return find_proc_mount(dir);

    }

}



bool make_block_device_writable(const std::string& dev) {

    int fd = unix_open(dev.c_str(), O_RDONLY | O_CLOEXEC);

    if (fd == -1) {
@@ -112,7 +138,13 @@ void remount_service(int fd, void* cookie) { 
    }



    bool success = true;

    property_get("ro.build.system_root_image", prop_buf, "");

    bool system_root = !strcmp(prop_buf, "true");

    if (system_root) {

        success &= remount_partition(fd, "/");

    } else {

        success &= remount_partition(fd, "/system");

    }

    success &= remount_partition(fd, "/vendor");

    success &= remount_partition(fd, "/oem");