mediamtx/internal/staticsources/rpicamera/camera_arm.go
2025-08-12 13:00:45 +02:00

391 lines
7 KiB
Go

//go:build (linux && arm) || (linux && arm64)
package rpicamera
import (
"debug/elf"
"fmt"
"os"
"os/exec"
"path/filepath"
"runtime"
"strconv"
"strings"
"sync"
"syscall"
"time"
"unsafe"
"github.com/bluenviron/mediacommon/v2/pkg/codecs/h264"
)
const (
libraryToCheckArchitecture = "libc.so.6"
dumpPrefix = "/dev/shm/mediamtx-rpicamera-"
executableName = "mtxrpicam"
)
var (
dumpMutex sync.Mutex
dumpCount = 0
dumpPath = ""
)
func ntpTime() syscall.Timespec {
var t syscall.Timespec
syscall.Syscall(syscall.SYS_CLOCK_GETTIME, 0, uintptr(unsafe.Pointer(&t)), 0)
return t
}
func monotonicTime() syscall.Timespec {
var t syscall.Timespec
syscall.Syscall(syscall.SYS_CLOCK_GETTIME, 1, uintptr(unsafe.Pointer(&t)), 0)
return t
}
func multiplyAndDivide(v, m, d int64) int64 {
secs := v / d
dec := v % d
return (secs*m + dec*m/d)
}
func getArchitecture(libPath string) (bool, error) {
f, err := os.Open(libPath)
if err != nil {
return false, err
}
defer f.Close()
ef, err := elf.NewFile(f)
if err != nil {
return false, err
}
defer ef.Close()
return (ef.FileHeader.Class == elf.ELFCLASS64), nil
}
func checkArchitecture() error {
byts, err := exec.Command("/sbin/ldconfig", "-p").Output()
if err != nil {
return fmt.Errorf("ldconfig failed: %w", err)
}
for _, line := range strings.Split(string(byts), "\n") {
f := strings.Split(line, " => ")
if len(f) == 2 && strings.Contains(f[1], libraryToCheckArchitecture) {
is64, err := getArchitecture(f[1])
if err != nil {
return err
}
if runtime.GOARCH == "arm" {
if !is64 {
return nil
}
} else {
if is64 {
return nil
}
}
}
}
if runtime.GOARCH == "arm" {
return fmt.Errorf("the operating system is 64-bit, you need the 64-bit server version")
}
return fmt.Errorf("the operating system is 32-bit, you need the 32-bit server version")
}
func dumpEmbedFSRecursive(src string, dest string) error {
files, err := mtxrpicam.ReadDir(src)
if err != nil {
return err
}
for _, f := range files {
if f.IsDir() {
err = os.Mkdir(filepath.Join(dest, f.Name()), 0o755)
if err != nil {
return err
}
err = dumpEmbedFSRecursive(filepath.Join(src, f.Name()), filepath.Join(dest, f.Name()))
if err != nil {
return err
}
} else {
buf, err := mtxrpicam.ReadFile(filepath.Join(src, f.Name()))
if err != nil {
return err
}
err = os.WriteFile(filepath.Join(dest, f.Name()), buf, 0o644)
if err != nil {
return err
}
}
}
return nil
}
func dumpComponent() error {
dumpMutex.Lock()
defer dumpMutex.Unlock()
if dumpCount > 0 {
dumpCount++
return nil
}
err := checkArchitecture()
if err != nil {
return err
}
dumpPath = dumpPrefix + strconv.FormatInt(time.Now().UnixNano(), 10)
err = os.Mkdir(dumpPath, 0o755)
if err != nil {
return err
}
files, err := mtxrpicam.ReadDir(".")
if err != nil {
os.RemoveAll(dumpPath)
return err
}
err = dumpEmbedFSRecursive(files[0].Name(), dumpPath)
if err != nil {
os.RemoveAll(dumpPath)
return err
}
err = os.Chmod(filepath.Join(dumpPath, executableName), 0o755)
if err != nil {
os.RemoveAll(dumpPath)
return err
}
dumpCount++
return nil
}
func freeComponent() {
dumpMutex.Lock()
defer dumpMutex.Unlock()
dumpCount--
if dumpCount == 0 {
os.RemoveAll(dumpPath)
}
}
type camera struct {
params params
onData func(int64, time.Time, [][]byte)
onDataSecondary func(int64, time.Time, []byte)
cmd *exec.Cmd
pipeOut *pipe
pipeIn *pipe
finalErr error
terminate chan struct{}
done chan struct{}
}
func (c *camera) initialize() error {
err := dumpComponent()
if err != nil {
return err
}
c.pipeOut, err = newPipe()
if err != nil {
freeComponent()
return err
}
c.pipeIn, err = newPipe()
if err != nil {
c.pipeOut.close()
freeComponent()
return err
}
env := []string{
"PIPE_CONF_FD=" + strconv.FormatInt(int64(c.pipeOut.readFD), 10),
"PIPE_VIDEO_FD=" + strconv.FormatInt(int64(c.pipeIn.writeFD), 10),
"LD_LIBRARY_PATH=" + dumpPath,
}
c.cmd = exec.Command(filepath.Join(dumpPath, executableName))
c.cmd.Stdout = os.Stdout
c.cmd.Stderr = os.Stderr
c.cmd.Env = env
c.cmd.Dir = dumpPath
err = c.cmd.Start()
if err != nil {
c.pipeOut.close()
c.pipeIn.close()
freeComponent()
return err
}
c.terminate = make(chan struct{})
c.done = make(chan struct{})
go c.run()
c.pipeOut.write(append([]byte{'c'}, c.params.serialize()...))
return nil
}
func (c *camera) close() {
close(c.terminate)
<-c.done
freeComponent()
}
func (c *camera) run() {
defer close(c.done)
c.finalErr = c.runInner()
}
func (c *camera) runInner() error {
cmdDone := make(chan error)
go func() {
cmdDone <- c.cmd.Wait()
}()
readDone := make(chan error)
go func() {
readDone <- c.runReader()
}()
for {
select {
case err := <-cmdDone:
c.pipeIn.close()
c.pipeOut.close()
<-readDone
return err
case err := <-readDone:
c.pipeIn.close()
c.pipeOut.write([]byte{'e'})
c.pipeOut.close()
<-cmdDone
return err
case <-c.terminate:
c.pipeIn.close()
<-readDone
c.pipeOut.write([]byte{'e'})
c.pipeOut.close()
<-cmdDone
return fmt.Errorf("terminated")
}
}
}
func (c *camera) runReader() error {
outer:
for {
buf, err := c.pipeIn.read()
if err != nil {
return err
}
switch buf[0] {
case 'e':
return fmt.Errorf(string(buf[1:]))
case 'r':
break outer
default:
return fmt.Errorf("unexpected data from pipe: '0x%.2x'", buf[0])
}
}
for {
buf, err := c.pipeIn.read()
if err != nil {
return err
}
switch buf[0] {
case 'e':
return fmt.Errorf(string(buf[1:]))
case 'd':
dts := int64(buf[8])<<56 | int64(buf[7])<<48 | int64(buf[6])<<40 | int64(buf[5])<<32 |
int64(buf[4])<<24 | int64(buf[3])<<16 | int64(buf[2])<<8 | int64(buf[1])
var nalus h264.AnnexB
err = nalus.Unmarshal(buf[9:])
if err != nil {
return err
}
unixNTP := ntpTime()
unixMono := monotonicTime()
// subtract from NTP the delay from now to the moment the frame was taken
ntp := time.Unix(int64(unixNTP.Sec), int64(unixNTP.Nsec))
deltaT := time.Duration(unixMono.Nano()-dts*1e3) * time.Nanosecond
ntp = ntp.Add(-deltaT)
c.onData(
multiplyAndDivide(dts, 90000, 1e6),
ntp,
nalus)
case 's':
dts := int64(buf[8])<<56 | int64(buf[7])<<48 | int64(buf[6])<<40 | int64(buf[5])<<32 |
int64(buf[4])<<24 | int64(buf[3])<<16 | int64(buf[2])<<8 | int64(buf[1])
unixNTP := ntpTime()
unixMono := monotonicTime()
// subtract from NTP the delay from now to the moment the frame was taken
ntp := time.Unix(int64(unixNTP.Sec), int64(unixNTP.Nsec))
deltaT := time.Duration(unixMono.Nano()-dts*1e3) * time.Nanosecond
ntp = ntp.Add(-deltaT)
c.onDataSecondary(
multiplyAndDivide(dts, 90000, 1e6),
ntp,
buf[9:])
default:
return fmt.Errorf("unexpected data from pipe: '0x%.2x'", buf[0])
}
}
}
func (c *camera) reloadParams(params params) {
c.pipeOut.write(append([]byte{'c'}, params.serialize()...))
}
func (c *camera) wait() error {
<-c.done
return c.finalErr
}