Improve performance of printf functions

This commit is contained in:
Justine Tunney 2021-04-24 13:58:34 -07:00
parent b107d2709f
commit dc6d11a031
39 changed files with 577 additions and 650 deletions

View file

@ -22,43 +22,55 @@
#include "libc/limits.h"
#include "libc/macros.internal.h"
#include "libc/nt/files.h"
#include "libc/sock/sock.h"
#include "libc/str/str.h"
#include "libc/sysv/errfuns.h"
struct VdprintfState {
int n;
int fd;
unsigned char buf[1024];
int n, t, fd;
char b[1024];
};
static int vdprintf_flush(struct VdprintfState *df, int n) {
int i, rc;
for (i = 0; i < n; i += rc) {
if ((rc = write(df->fd, df->buf + i, n - i)) == -1) {
return -1;
static int vdprintf_putc(const char *s, struct VdprintfState *t, size_t n) {
struct iovec iov[2];
if (n) {
if (t->n + n < sizeof(t->b)) {
memcpy(t->b + t->n, s, n);
t->n += n;
} else {
iov[0].iov_base = t->b;
iov[0].iov_len = t->n;
iov[1].iov_base = s;
iov[1].iov_len = n;
if (WritevUninterruptible(t->fd, iov, 2) == -1) {
return -1;
}
t->t += t->n;
t->n = 0;
}
}
return 0;
}
static int vdprintf_putc(int c, struct VdprintfState *df) {
df->buf[df->n++ & (ARRAYLEN(df->buf) - 1)] = c & 0xff;
if ((df->n & (ARRAYLEN(df->buf) - 1))) {
return 0;
} else {
return vdprintf_flush(df, ARRAYLEN(df->buf));
}
}
/**
* Formats string directly to system i/o device.
* @asyncsignalsafe
* @vforksafe
*/
int(vdprintf)(int fd, const char *fmt, va_list va) {
struct VdprintfState df;
df.n = 0;
df.fd = fd;
if (__fmt(vdprintf_putc, &df, fmt, va) == -1) return -1;
if (vdprintf_flush(&df, df.n & (ARRAYLEN(df.buf) - 1)) == -1) return -1;
return df.n;
struct iovec iov[1];
struct VdprintfState t;
t.n = 0;
t.t = 0;
t.fd = fd;
if (__fmt(vdprintf_putc, &t, fmt, va) == -1) return -1;
if (t.n) {
iov[0].iov_base = t.b;
iov[0].iov_len = t.n;
if (WritevUninterruptible(t.fd, iov, 1) == -1) {
return -1;
}
t.t += t.n;
}
return t.t;
}