92 lines
3.6 KiB
Go
92 lines
3.6 KiB
Go
package buildinfo
|
|
|
|
import (
|
|
"runtime"
|
|
|
|
"golang.org/x/sys/cpu"
|
|
)
|
|
|
|
// GetSupportedGOARM returns the ARM compatibility level of the current CPU.
|
|
//
|
|
// Returns the integer value that can be set for the GOARM variable to
|
|
// build with this level as target, a value which normally corresponds to the
|
|
// ARM architecture version number, although it is the floating point hardware
|
|
// support which is the decicive factor.
|
|
//
|
|
// Only relevant for 32-bit ARM architectures, where GOARCH=arm, which means
|
|
// ARMv7 and lower (ARMv8 is GOARCH=arm64 and GOARM is not considered).
|
|
// Highest possible value is therefore 7, while other possible values are
|
|
// 6 (for ARMv6) and 5 (for ARMv5, which is the lowest currently supported
|
|
// in go. Returns value 0 for anything else.
|
|
//
|
|
// See also:
|
|
//
|
|
// https://go.dev/src/runtime/os_linux_arm.go
|
|
// https://github.com/golang/go/wiki/GoArm
|
|
func GetSupportedGOARM() int {
|
|
if runtime.GOARCH == "arm" && cpu.Initialized {
|
|
// This CPU is an ARM (32-bit), and cpu.Initialized true means its
|
|
// features could be retrived on current GOOS so that we can check
|
|
// for floating point hardware support.
|
|
if cpu.ARM.HasVFPv3 {
|
|
// This CPU has VFPv3 floating point hardware, which means it can
|
|
// run programs built with any GOARM value, 7 and lower.
|
|
return 7
|
|
} else if cpu.ARM.HasVFP {
|
|
// This CPU has VFP floating point hardware, but not VFPv3, which
|
|
// means it can run programs built with GOARM value 6 and lower,
|
|
// but not 7.
|
|
return 6
|
|
} else {
|
|
// This CPU has no VFP floating point hardware, which means it can
|
|
// only run programs built with GOARM value 5, which is minimum supported.
|
|
// Note that the CPU can still in reality be based on e.g. ARMv7
|
|
// architecture, but simply lack hardfloat support.
|
|
return 5
|
|
}
|
|
}
|
|
return 0
|
|
}
|
|
|
|
// GetArch tells the rclone executable's architecture target.
|
|
func GetArch() string {
|
|
// Get the running program's architecture target.
|
|
arch := runtime.GOARCH
|
|
|
|
// For ARM architectures there are several variants, with different
|
|
// inconsistent and ambiguous naming.
|
|
//
|
|
// The most interesting thing here is which compatibility level of go is
|
|
// used, as controlled by GOARM build variable. We cannot in runtime get
|
|
// the actual value of GOARM used for building this program, but we can
|
|
// check the value supported by the current CPU by calling GetSupportedGOARM.
|
|
// This means we return information about the compatibility level (GOARM
|
|
// value) supported, when the current rclone executable may in reality be
|
|
// built with a lower level.
|
|
//
|
|
// Note that the kernel architecture, as returned by "uname -m", is not
|
|
// considered or included in results here, but it is included in the output
|
|
// from function GetOSVersion. It can have values such as armv6l, armv7l,
|
|
// armv8l, arm64 and aarch64, which may give relevant information. But it
|
|
// can also simply have value "arm", or it can have value "armv7l" for a
|
|
// processor based on ARMv7 but without floating point hardware - which
|
|
// means it in go needs to be built in ARMv5 compatibility mode (GOARM=5).
|
|
if arch == "arm64" {
|
|
// 64-bit ARM architecture, known as AArch64, was introduced with ARMv8.
|
|
// In go this architecture is a specific one, separate from other ARMs.
|
|
arch += " (ARMv8 compatible)"
|
|
} else if arch == "arm" {
|
|
// 32-bit ARM architecture, which is ARMv7 and lower.
|
|
// In go there are different compatibility levels represented by ARM
|
|
// architecture version number (like 5, 6 or 7).
|
|
switch GetSupportedGOARM() {
|
|
case 7:
|
|
arch += " (ARMv7 compatible)"
|
|
case 6:
|
|
arch += " (ARMv6 compatible)"
|
|
case 5:
|
|
arch += " (ARMv5 compatible, no hardfloat)"
|
|
}
|
|
}
|
|
return arch
|
|
}
|