cosmopolitan/libc/stdio/vfprintf.c
2021-04-24 13:58:50 -07:00

50 lines
2.5 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=8 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/fmt/fmt.h"
#include "libc/limits.h"
#include "libc/stdio/stdio.h"
#include "libc/sysv/errfuns.h"
struct state {
FILE *f;
int n;
};
static int vfprintfputchar(const char *s, struct state *t, size_t n) {
if (n) {
if (n == 1 && *s != '\n' && t->f->beg < t->f->size &&
t->f->bufmode != _IONBF) {
t->f->buf[t->f->beg++] = *s;
} else if (!fwrite(s, 1, n, t->f)) {
return -1;
}
t->n += n;
}
return 0;
}
int(vfprintf)(FILE *f, const char *fmt, va_list va) {
struct state st[1] = {{f, 0}};
if (__fmt(vfprintfputchar, st, fmt, va) != -1) {
return st->n;
} else {
return -1;
}
}