/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 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/bits/safemacros.internal.h"
#include "libc/calls/calls.h"
#include "libc/fmt/fmt.h"
#include "libc/macros.internal.h"
#include "libc/runtime/runtime.h"
#include "libc/stdio/stdio.h"
#include "libc/stdio/temp.h"
#include "libc/str/str.h"

/**
 * Creates a temporary file.
 *
 * @see mkostempsm(), kTmpPath
 */
FILE *tmpfile(void) {
  int fd;
  char *tmp, *sep, tpl[PATH_MAX];
  tmp = firstnonnull(getenv("TMPDIR"), kTmpPath);
  sep = !isempty(tmp) && !endswith(tmp, "/") ? "/" : "";
  if ((snprintf)(tpl, PATH_MAX, "%s%stmp.%s.XXXXXX", tmp, sep,
                 firstnonnull(program_invocation_short_name, "unknown")) <=
      PATH_MAX) {
    if ((fd = mkostemps(tpl, 0, 0)) != -1) {
      return fdopen(fd, "w+");
    }
  }
  return NULL;
}