README
¶
fat
A File Allocation Table implementation written in Go. Intended for use in embedded systems with SD cards, USBs, MMC devices and also usable with an in-RAM representation. Inspired by FatFs.
This is a Work in Progress.
How to install package with newer versions of Go (+1.16):
go mod download github.com/soypat/fat@latest
Basic usage example
The following example does the following:
- Mounts a FAT filesystem to the
fat.FStype. - Creates a new empty file called
newfile.txt, replacing any existing file. - Writes
Hello, World!to that file. - Closes the file to synchronize pending changes to the FAT filesystem.
- Opens the file in read mode and reads all of it's contents and prints them to standard output.
package main
import "github.com/soypat/fat"
func main() {
// device could be an SD card, RAM, or anything that implements the BlockDevice interface.
device := NewFATDevice()
var fs fat.FS
err := fs.Mount(device, device.BlockSize(), fat.ModeRW)
if err != nil {
panic(err)
}
var file fat.File
err = fs.OpenFile(&file, "newfile.txt", fat.ModeCreateAlways|fat.ModeWrite)
if err != nil {
panic(err)
}
_, err = file.Write([]byte("Hello, World!"))
if err != nil {
panic(err)
}
err = file.Close()
if err != nil {
panic(err)
}
// Read back the file:
err = fs.OpenFile(&file, "newfile.txt", fat.ModeRead)
if err != nil {
panic(err)
}
data, err := io.ReadAll(&file)
if err != nil {
panic(err)
}
fmt.Println(string(data))
file.Close()
// Output: Hello, World!
}
Documentation
¶
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type BlockDevice ¶
type Dir ¶
type Dir struct {
// contains filtered or unexported fields
}
Dir represents an open FAT directory.
type FS ¶
type FS struct {
// contains filtered or unexported fields
}
Example (Basic_usage) ¶
package main
import (
"fmt"
"io"
"github.com/soypat/fat"
)
func main() {
// device could be an SD card, RAM, or anything that implements the BlockDevice interface.
device := fat.DefaultFATByteBlocks(32000)
var fs fat.FS
err := fs.Mount(device, device.BlockSize(), fat.ModeRW)
if err != nil {
panic(err)
}
var file fat.File
err = fs.OpenFile(&file, "newfile.txt", fat.ModeCreateAlways|fat.ModeWrite)
if err != nil {
panic(err)
}
_, err = file.Write([]byte("Hello, World!"))
if err != nil {
panic(err)
}
err = file.Close()
if err != nil {
panic(err)
}
// Read back the file:
err = fs.OpenFile(&file, "newfile.txt", fat.ModeRead)
if err != nil {
panic(err)
}
data, err := io.ReadAll(&file)
if err != nil {
panic(err)
}
fmt.Println(string(data))
file.Close()
}
Output: Hello, World!
func (*FS) Mount ¶
func (fsys *FS) Mount(bd BlockDevice, blockSize int, mode Mode) error
Mount mounts the FAT file system on the given block device and sector size. It immediately invalidates previously open files and directories pointing to the same FS. Mode should be ModeRead, ModeWrite, or both.
type File ¶
type File struct {
// contains filtered or unexported fields
}
func (*File) Read ¶
Read reads up to len(buf) bytes from the File. It implements the io.Reader interface.
type FileInfo ¶
type FileInfo struct {
// contains filtered or unexported fields
}
func (*FileInfo) AlternateName ¶
AlternateName returns the alternate name of the file.
type FormatConfig ¶
type Formatter ¶
type Formatter struct {
// contains filtered or unexported fields
}
func (*Formatter) Format ¶
func (f *Formatter) Format(bd BlockDevice, blocksize, fsSizeInBlocks int, cfg FormatConfig) error
type Mode ¶
type Mode uint8
Mode represents the file access mode used in Open.
const ( ModeRead Mode = Mode(faRead) ModeWrite Mode = Mode(faWrite) ModeRW Mode = ModeRead | ModeWrite ModeCreateNew Mode = Mode(faCreateNew) ModeCreateAlways Mode = Mode(faCreateAlways) ModeOpenExisting Mode = Mode(faOpenExisting) ModeOpenAppend Mode = Mode(faOpenAppend) )
File access modes for calling Open.
Source Files
Directories