Some hw breakpoint fixes #52
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Enable usage of dr1-dr3. Clear control bits when a breakpoint is disabled. Use DR_LEN_1 instead of DR_LEN_8 so breakpoint work on unaligned adresses. Fixes go-delve#51.
| @@ -50,6 +51,15 @@ func PtracePokeUser(tid int, off, addr uintptr) error { | |||
| return nil | |||
| } | |||
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| func PtracePeekUser(tid int, off uintptr) (uintptr, error) { | |||
| var x uintptr // XXX: this should not be necessary | |||
| ret, _, err := syscall.Syscall6(syscall.SYS_PTRACE, syscall.PTRACE_PEEKUSR, uintptr(tid), uintptr(off), uintptr(unsafe.Pointer(&x)), 0, 0) | |||
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ret will never be anything of interest to us here. The actual value from this ptrace request will be stored in x. The ptrace API is to provide an address and data, and for reads (PEEK) the data stored in the requested address will be placed in the data argument, which here would be x.
ret will be 0 every time, whereas x will hold to value of interest.
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On Sun, Jan 25, 2015 at 12:32:55PM -0800, Derek Parker wrote:
@@ -50,6 +51,15 @@ func PtracePokeUser(tid int, off, addr uintptr) error {
return nil
}+func PtracePeekUser(tid int, off uintptr) (uintptr, error) {
- var x uintptr // XXX: this should not be necessary
- ret, _, err := syscall.Syscall6(syscall.SYS_PTRACE, syscall.PTRACE_PEEKUSR, uintptr(tid), uintptr(off), uintptr(unsafe.Pointer(&x)), 0, 0)
retwill never be anything of interest to us here. The actual value
from this ptrace request will be stored inx. The ptrace API is to
provide an address and data, and for reads (PEEK) the data stored in
the requested address will be placed in the data argument, which here
would bex.
retwill be 0 every time, whereasxwill hold to value of
interest.
Indeed. The man page apparently documents the ABI of the glibc wrapper.
Fixed.
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Thanks! |
* Added optus proxy peering module * Added optus proxy peering module * Added optus proxy peering module
Enable usage of dr1-dr3. Clear control bits when a breakpoint
is disabled. Use DR_LEN_1 instead of DR_LEN_8 so breakpoint work on
unaligned adresses.
Fixes #51.