android系统如何获得外置卡路径
内置与外置卡路径实际是存在系统文件"system/etc/vold.fstab"中，可以用一下语句获得路径。
Environment.getRootDirectory().getAbsoluteFile() + File.separator + "etc" + File.separator + "vold.fstab"；
联想K860i的system/etc/vold.fstab文件内容如下：
## Vold 2.0 Generic fstab
## - San Mehat ([email protected])
##
#######################
## Regular device mount
##
## Format: dev_mount <label> <mount_point> <part> <sysfs_path1...>
## label - Label for the volume
## mount_point - Where the volume will be mounted
## part - Partition # (1 based), or 'auto' for first usable partition.
## <sysfs_path> - List of sysfs paths to source devices
######################
dev_mount sdcard /mnt/sdcard 1 /devices/platform/dw_mmc/mmc_host/mmc0
dev_mount extra_sd /mnt/sdcard/extra_sd auto /devices/platform/s3c-sdhci.2/mmc_host/mmc1
联想K860i的sd卡路径是：
mnt/sdcard 内置卡，mnt/sdcard/extra_sd外置卡，与结果相符。
目前只在联想K860i和公司的样机G2，G10，G6+，D6上测试OK。
G2,/storage/sdcard0内置卡,/storage/sdcard1外置卡
dev_mount sdcard /storage/sdcard0 emmc@fat /devices/platform/goldfish_mmc.0 /devices/platform/mtk-sd.0/mmc_host
dev_mount sdcard2 /storage/sdcard1 auto /devices/platform/goldfish_mmc.1 /devices/platform/mtk-sd.1/mmc_host
G10&G10+,/mnt/sdcard外置卡,/mnt/external_sd外置卡,/mnt/usb_storageU盘
dev_mount flash /mnt/sdcard auto /dev/block/mtd/by-name/user
dev_mount sdcard /mnt/external_sd auto /devices/platform/rk29_sdmmc.0/mmc_host/mmc0
dev_mount udisk /mnt/usb_storage auto /devices/platform/usb20_host/usb /devices/platform/usb20_otg/usb
G6+,/mnt/sdcard内置卡,/mnt/external_sd外置卡
dev_mount flash /mnt/sdcard auto /devices/virtual/mtd/mtd9/mtdblock9
dev_mount sdcard /mnt/external_sd auto /devices/platform/rk29_sdmmc.0/mmc_host/mmc0
D6,/mnt/sdcard内置卡,/mnt/extsd外置卡,/mnt/usbhost1U盘
dev_mount sdcard/mnt/sdcard auto/devices/virtual/block/nandj
dev_mount extsd/mnt/extsd auto/devices/platform/sunxi-mmc.1/mmc_host /devices/platform/sunxi-mmc.0/mmc_host
dev_mount usbhost1/mnt/usbhost1 auto/devices/platform/sw-ehci.1 /devices/platform/sw_hcd_host0/devices/platform/sw-ohci.1
G6,,/mnt/sdcard内置卡,/mnt/extsd外置卡,/mnt/usbhost1U盘
dev_mount sdcard/mnt/sdcard auto/devices/virtual/block/nandj
dev_mount extsd/mnt/extsd auto/devices/platform/sunxi-mmc.1/mmc_host /devices/platform/sunxi-mmc.0/mmc_host
dev_mount usbhost1/mnt/usbhost1 auto/devices/platform/sw-ehci.1 /devices/platform/sw_hcd_host0/devices/platform/sw-ehci.2a
D6和G6有所不同，不是用空格隔开，而是用TAB隔开。
获取盘符类：
public class Dev_MountInfo implements IDev {/*
#######################
## Regular device mount
##
## Format: dev_mount <label> <mount_point> <part> <sysfs_path1...>
## label - Label for the volume
## mount_point - Where the volume will be mounted
## part - Partition # (1 based), or 'auto' for first usable partition.
## <sysfs_path> - List of sysfs paths to source devices
######################
*/
public final String HEAD = "dev_mount";
private final int DEV_INTERNAL = 0;
private final int DEV_EXTERNAL = 1;
private final int DEV_USB = 2;//这个可能没有，上面两个一般都会有
private ArrayList<String> cache = new ArrayList<String>();
private static Dev_MountInfo dev;
private DevInfo info;
private final File VOLD_FSTAB = new File(
Environment.getRootDirectory().getAbsoluteFile()
+ File.separator + "etc"
+ File.separator + "vold.fstab");
public static Dev_MountInfo getInstance() {
if (null == dev)
dev = new Dev_MountInfo();
return dev;
}
private DevInfo getInfo(final int device) {
try {
initVoldFstabToCache();
} catch (IOException e) {
e.printStackTrace();
}
info = new DevInfo();
if(device < cache.size()){
String[] sinfo = cache.get(device).split(" |\t");
if(sinfo.length >= 5){
info.setLabel(sinfo[1]);
info.setMount_point(sinfo[2]);
info.setPart(sinfo[3]);
info.setSysfs_path(sinfo[4]);
}
}
return info;
}
/**
* init the words into the cache array
* @throws IOException
*/
private void initVoldFstabToCache() throws IOException {
cache.clear();
BufferedReader br = new BufferedReader(new FileReader(VOLD_FSTAB));
String tmp = null;
while ((tmp = br.readLine()) != null) {
// the words startsWith "dev_mount" are the SD info
if (tmp.startsWith(HEAD)) {
cache.add(tmp);
Log.v("xcl", tmp);
}
}
br.close();
cache.trimToSize();
}
public class DevInfo {
private String label, mount_point, part;
private String sysfs_path;
public String getLabel() {
return label;
}
private void setLabel(String label) {
this.label = label;
}
public String getMount_point() {
return mount_point;
}
private void setMount_point(String mount_point) {
this.mount_point = mount_point;
}
public String getPart() {
return part;
}
private void setPart(String part) {
this.part = part;
}
public String getSysfs_path() {
return sysfs_path;
}
private void setSysfs_path(String sysfs_path) {
this.sysfs_path = sysfs_path;
}
}
public DevInfo getInternalInfo() {
return getInfo(DEV_INTERNAL);
}
public DevInfo getExternalInfo() {
return getInfo(DEV_EXTERNAL);
}
public DevInfo getUSBInfo(){
return getInfo(DEV_USB);
}
}
interface IDev {
DevInfo getInternalInfo();
DevInfo getExternalInfo();
}
调用代码：
//获得各盘符路径
Dev_MountInfo dev = Dev_MountInfo.getInstance();
DevInfo info = dev.getInternalInfo();
this.diskInternal = info.getMount_point();
//Environment.getExternalStorageDirectory() 这两个要是不一样咋办
info = dev.getExternalInfo();
this.diskExternal = info.getMount_point();
info = dev.getUSBInfo();
this.diskUSB = info.getMount_point();
该方法基于以下几点猜测：
1.挂载盘符的文件一定是 system/etc/vold.fstab
2.挂载盘符顺序一定是 内置卡 外置卡 U盘，而且前面必须有
3.每个盘符挂载信息都是如下排序 Format: dev_mount <label> <mount_point> <part> <sysfs_path1...>
4.