ErrorCode PTrace::readBytes(ProcessThreadId const &ptid, Address const &address,
void *buffer, size_t length, size_t *count,
bool nullTerm) {
pid_t pid;
CHK(ptidToPid(ptid, pid));
bool foundNull = false;
size_t nread = 0;
uintptr_t base = address;
uintptr_t *words = (uintptr_t *)buffer;
if (length == 0 || buffer == nullptr) {
if (count != nullptr) {
*count = 0;
}
return kSuccess;
}
while (length > 0) {
union {
uintptr_t word;
uint8_t bytes[sizeof(uintptr_t)];
} data;
size_t ncopy = std::min(length, sizeof(uintptr_t));
errno = 0;
if (ncopy < sizeof(uintptr_t)) {
data.word = wrapPtrace(PTRACE_PEEKDATA, pid, base + nread, nullptr);
if (errno == 0) {
std::memcpy(words, data.bytes, ncopy);
}
} else {
*words = wrapPtrace(PTRACE_PEEKDATA, pid, base + nread, nullptr);
}
if (errno != 0)
break;
if (nullTerm && strnlen((char *)words, ncopy) < ncopy) {
foundNull = true;
break;
}
length -= ncopy;
nread += ncopy;
words++;
}
if (count != nullptr) {
*count = nread;
}
if (errno != 0)
return Platform::TranslateError();
if (nullTerm && !foundNull)
return kErrorNameTooLong;
return kSuccess;
}
ErrorCode PTrace::writeMemory(ProcessThreadId const &ptid,
Address const &address, void const *buffer,
size_t length, size_t *count) {
pid_t pid;
CHK(ptidToPid(ptid, pid));
uintptr_t base = address;
struct ptrace_io_desc desc;
if (length == 0 || buffer == nullptr) {
if (count != nullptr)
*count = 0;
return kSuccess;
}
desc.piod_op = PIOD_WRITE_D;
desc.piod_offs = (void *)base;
desc.piod_addr = (void *)buffer;
desc.piod_len = length;
if (wrapPtrace(PT_IO, pid, &desc, nullptr) < 0)
return Platform::TranslateError();
if (count != nullptr)
*count = desc.piod_len;
return kSuccess;
}
ErrorCode PTrace::getSigInfo(ProcessThreadId const &ptid, siginfo_t &si) {
pid_t pid;
CHK(ptidToPid(ptid, pid));
if (wrapPtrace(PTRACE_GETSIGINFO, pid, nullptr, &si) < 0)
return Platform::TranslateError();
return kSuccess;
}
ErrorCode PTrace::getLwpInfo(ProcessThreadId const &ptid,
struct ptrace_lwpinfo *lwpinfo) {
pid_t pid;
CHK(ptidToPid(ptid, pid));
if (wrapPtrace(PT_LWPINFO, pid, lwpinfo, sizeof(struct ptrace_lwpinfo)) < 0)
return Platform::TranslateError();
return kSuccess;
}
ErrorCode PTrace::getSigInfo(ProcessThreadId const &ptid, siginfo_t &si) {
struct ptrace_lwpinfo lwpinfo;
pid_t pid;
CHK(ptidToPid(ptid, pid));
if (wrapPtrace(PT_LWPINFO, pid, &lwpinfo, sizeof lwpinfo) < 0)
return Platform::TranslateError();
si = lwpinfo.pl_siginfo;
return kSuccess;
}
ErrorCode PTrace::writeMemory(ProcessThreadId const &ptid,
Address const &address, void const *buffer,
size_t length, size_t *count) {
pid_t pid;
CHK(ptidToPid(ptid, pid));
size_t nwritten = 0;
uintptr_t base = address;
uintptr_t const *words = (uintptr_t const *)buffer;
if (length == 0 || buffer == nullptr) {
if (count != nullptr) {
*count = 0;
}
return kSuccess;
}
while (length > 0) {
union {
uintptr_t word;
uint8_t bytes[sizeof(uintptr_t)];
} data;
size_t ncopy = std::min(length, sizeof(uintptr_t));
errno = 0;
if (ncopy < sizeof(uintptr_t)) {
data.word = wrapPtrace(PTRACE_PEEKDATA, pid, base + nwritten, nullptr);
if (errno == 0) {
std::memcpy(data.bytes, words, ncopy);
wrapPtrace(PTRACE_POKEDATA, pid, base + nwritten, data.word);
}
} else {
wrapPtrace(PTRACE_POKEDATA, pid, base + nwritten, *words);
}
if (errno != 0)
break;
length -= ncopy;
nwritten += ncopy;
words++;
}
if (errno != 0)
return Platform::TranslateError();
if (count != nullptr) {
*count = nwritten;
}
return kSuccess;
}
ErrorCode PTrace::wait(ProcessThreadId const &ptid, int *status) {
pid_t pid;
CHK(ptidToPid(ptid, pid));
int stat;
pid_t ret;
ret = waitpid(pid, &stat, __WALL);
if (ret < 0)
return kErrorProcessNotFound;
DS2ASSERT(ret == pid);
if (status != nullptr) {
*status = stat;
}
return kSuccess;
}
