kaguya
81 lines
1.7 KiB
C++
81 lines
1.7 KiB
C++
|
|
#include <sys/uio.h>
|
|
#include <unistd.h>
|
|
#include <errno.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <limits.h>
|
|
|
|
#include <frg/vector.hpp>
|
|
#include <mlibc/allocator.hpp>
|
|
#include <mlibc/debug.hpp>
|
|
#include <mlibc/posix-sysdeps.hpp>
|
|
#include <bits/ensure.h>
|
|
|
|
ssize_t readv(int fd, const struct iovec *iovs, int iovc) {
|
|
ssize_t read_bytes = 0;
|
|
|
|
auto sysdep = MLIBC_CHECK_OR_ENOSYS(mlibc::sys_readv, -1);
|
|
|
|
if (int e = sysdep(fd, iovs, iovc, &read_bytes); e) {
|
|
errno = e;
|
|
return -1;
|
|
}
|
|
|
|
return read_bytes;
|
|
}
|
|
|
|
ssize_t writev(int fd, const struct iovec *iovs, int iovc) {
|
|
__ensure(iovc);
|
|
|
|
ssize_t written = 0;
|
|
|
|
auto sysdep = mlibc::sys_writev;
|
|
if(sysdep) {
|
|
int e = sysdep(fd, iovs, iovc, &written);
|
|
if(e) {
|
|
errno = e;
|
|
return -1;
|
|
}
|
|
return written;
|
|
}
|
|
|
|
// TODO: this implementation is not safe to use in signal contexts
|
|
mlibc::infoLogger() << "mlibc: falling back to signal-unsafe writev implementation!" << frg::endlog;
|
|
size_t bytes = 0;
|
|
for(int i = 0; i < iovc; i++) {
|
|
if(SSIZE_MAX - bytes < iovs[i].iov_len) {
|
|
errno = EINVAL;
|
|
return -1;
|
|
}
|
|
bytes += iovs[i].iov_len;
|
|
}
|
|
frg::vector<char, MemoryAllocator> buffer{getAllocator()};
|
|
buffer.resize(bytes);
|
|
|
|
size_t to_copy = bytes;
|
|
char *bp = buffer.data();
|
|
for(int i = 0; i < iovc; i++) {
|
|
size_t copy = frg::min(iovs[i].iov_len, to_copy);
|
|
|
|
bp = (char *)mempcpy((void *)bp, (void *)iovs[i].iov_base, copy);
|
|
|
|
to_copy -= copy;
|
|
if(to_copy == 0)
|
|
break;
|
|
}
|
|
|
|
written = write(fd, buffer.data(), bytes);
|
|
return written;
|
|
}
|
|
|
|
ssize_t preadv(int, const struct iovec *, int, off_t) {
|
|
__ensure(!"Not implemented");
|
|
__builtin_unreachable();
|
|
}
|
|
|
|
ssize_t pwritev(int, const struct iovec *, int, off_t) {
|
|
__ensure(!"Not implemented");
|
|
__builtin_unreachable();
|
|
}
|