cosmopolitan/test/libc/calls/pread_test.c

/*-*- 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 2022 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/sysv/consts/o.h"
#include "libc/testlib/testlib.h"

int fd;
char buf[8];
char testlib_enable_tmp_setup_teardown;

__attribute__((__constructor__)) static void init(void) {
  pledge("stdio rpath wpath cpath fattr", 0);
  errno = 0;
}

TEST(dog, testReadPastEof_returnsZero) {
  EXPECT_NE(-1, (fd = open("a", O_RDWR | O_CREAT | O_TRUNC, 0644)));
  EXPECT_EQ(0, pread(fd, buf, 8, 0));
  EXPECT_EQ(0, close(fd));
}

TEST(dog, testReadOverlapsEof_returnsShortNumber) {
  EXPECT_NE(-1, (fd = open("b", O_RDWR | O_CREAT | O_TRUNC, 0644)));
  EXPECT_EQ(4, pwrite(fd, buf, 4, 0));
  EXPECT_EQ(4, pread(fd, buf, 8, 0));
  EXPECT_EQ(0, close(fd));
}