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unix: remove pread/preadv conditionals

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This commit is contained in:
Ben Noordhuis 2023-10-01 14:10:20 +02:00
parent c03569f0df
commit 663d88b677
1 changed files with 33 additions and 110 deletions
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143
src/unix/fs.c
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@ -46,20 +46,6 @@
#include <fcntl.h>
#include <poll.h>
#if defined(__DragonFly__) || \
defined(__FreeBSD__) || \
defined(__OpenBSD__) || \
defined(__NetBSD__)
# define HAVE_PREADV 1
#else
# define HAVE_PREADV 0
#endif
/* preadv() and pwritev() were added in Android N (level 24) */
#if defined(__linux__) && !(defined(__ANDROID__) && __ANDROID_API__ < 24)
# define TRY_PREADV 1
#endif
#if defined(__linux__)
# include <sys/sendfile.h>
#endif
@ -410,116 +396,35 @@ static ssize_t uv__fs_open(uv_fs_t* req) {
}
#if !HAVE_PREADV
static ssize_t uv__fs_preadv(uv_file fd,
uv_buf_t* bufs,
unsigned int nbufs,
off_t off) {
uv_buf_t* buf;
uv_buf_t* end;
ssize_t result;
ssize_t rc;
size_t pos;
assert(nbufs > 0);
result = 0;
pos = 0;
buf = bufs + 0;
end = bufs + nbufs;
for (;;) {
do
rc = pread(fd, buf->base + pos, buf->len - pos, off + result);
while (rc == -1 && errno == EINTR);
if (rc == 0)
break;
if (rc == -1 && result == 0)
return UV__ERR(errno);
if (rc == -1)
break; /* We read some data so return that, ignore the error. */
pos += rc;
result += rc;
if (pos < buf->len)
continue;
pos = 0;
buf += 1;
if (buf == end)
break;
}
return result;
}
#endif
static ssize_t uv__fs_read(uv_fs_t* req) {
#if TRY_PREADV
static _Atomic int no_preadv;
#endif
static ssize_t uv__fs_read_do(int fd,
const struct iovec* bufs,
unsigned int nbufs,
int64_t off) {
unsigned int iovmax;
ssize_t result;
iovmax = uv__getiovmax();
if (req->nbufs > iovmax)
req->nbufs = iovmax;
if (nbufs > iovmax)
nbufs = iovmax;
if (req->off < 0) {
if (req->nbufs == 1)
result = read(req->file, req->bufs[0].base, req->bufs[0].len);
if (off < 0) {
if (nbufs == 1)
result = read(fd, bufs->iov_base, bufs->iov_len);
else
result = readv(req->file, (struct iovec*) req->bufs, req->nbufs);
result = readv(fd, bufs, nbufs);
} else {
if (req->nbufs == 1) {
result = pread(req->file, req->bufs[0].base, req->bufs[0].len, req->off);
goto done;
}
#if HAVE_PREADV
result = preadv(req->file, (struct iovec*) req->bufs, req->nbufs, req->off);
#else
# if TRY_PREADV
if (atomic_load_explicit(&no_preadv, memory_order_relaxed)) retry:
# endif
{
result = uv__fs_preadv(req->file, req->bufs, req->nbufs, req->off);
}
# if TRY_PREADV
else {
result = preadv(req->file,
(struct iovec*) req->bufs,
req->nbufs,
req->off);
if (result == -1 && errno == ENOSYS) {
atomic_store_explicit(&no_preadv, 1, memory_order_relaxed);
goto retry;
}
}
# endif
#endif
if (nbufs == 1)
result = pread(fd, bufs->iov_base, bufs->iov_len, off);
else
result = preadv(fd, bufs, nbufs, off);
}
done:
/* Early cleanup of bufs allocation, since we're done with it. */
if (req->bufs != req->bufsml)
uv__free(req->bufs);
req->bufs = NULL;
req->nbufs = 0;
#ifdef __PASE__
/* PASE returns EOPNOTSUPP when reading a directory, convert to EISDIR */
if (result == -1 && errno == EOPNOTSUPP) {
struct stat buf;
ssize_t rc;
rc = uv__fstat(req->file, &buf);
rc = uv__fstat(fd, &buf);
if (rc == 0 && S_ISDIR(buf.st_mode)) {
errno = EISDIR;
}
@ -530,6 +435,24 @@ done:
}
static ssize_t uv__fs_read(uv_fs_t* req) {
const struct iovec* iov;
ssize_t result;
iov = (const struct iovec*) req->bufs;
result = uv__fs_read_do(req->file, iov, req->nbufs, req->off);
/* Early cleanup of bufs allocation, since we're done with it. */
if (req->bufs != req->bufsml)
uv__free(req->bufs);
req->bufs = NULL;
req->nbufs = 0;
return result;
}
static int uv__fs_scandir_filter(const uv__dirent_t* dent) {
return strcmp(dent->d_name, ".") != 0 && strcmp(dent->d_name, "..") != 0;
}