Add more tests of getline

There is very little test coverage for getline (only a minimal
stdio-common/tstgetln.c which doesn't verify anything about the
results of the getline calls).  Add some more thorough tests
(generally using fopencookie for convenience in testing various cases
for what the input and possible errors / EOF in the file read might
look like).

Note the following regarding testing of error cases:

* Nothing is said in the specifications about what if anything might
  be written into the buffer, and whether it might be reallocated, in
  error cases.  The expectation of the tests (required to avoid memory
  leaks on error) is that at least on error cases, the invariant that
  lineptr points to at least n bytes is maintained.

* The optional EOVERFLOW error case specified in POSIX, "The number of
  bytes to be written into the buffer, including the delimiter
  character (if encountered), would exceed {SSIZE_MAX}.", doesn't seem
  practically testable, as any case reading so many characters (half
  the address space) would also be liable to run into allocation
  failure along (ENOMEM) the way.

* If a read error occurs part way through reading an input line, it
  seems unclear whether a partial line should be returned by getline
  (avoid input getting lost), which is what glibc does at least in the
  fopencookie case used in this test, or whether getline should return
  -1 (error) (so avoiding the program misbehaving by processing a
  truncated line as if it were complete).  (There was a short,
  inconclusive discussion about this on the Austin Group list on 9-10
  November 2014.)

* The POSIX specification of getline inherits errors from fgetc.  I
  didn't try to cover fgetc errors systematically, just one example of
  such an error.

Tested for x86_64 and x86.

diff --git a/stdio-common/Makefile b/stdio-common/Makefile
index a91754f52def6a527955db05d8688eab4cd1a7c3..948d960cccc0bc3a3935b8b88bcbe68870c9d5c1 100644 (file)
--- a/stdio-common/Makefile
+++ b/stdio-common/Makefile
@@ -218,6 +218,8 @@ tests := \
   tst-fphex-wide \
   tst-fseek \
   tst-fwrite \
+  tst-getline \
+  tst-getline-enomem \
   tst-gets \
   tst-grouping \
   tst-grouping2 \
@@ -313,6 +315,8 @@ tests-special += \
 ifeq (yes,$(build-shared))
 ifneq ($(PERL),no)
 tests-special += \
+  $(objpfx)tst-getline-enomem-mem.out \
+  $(objpfx)tst-getline-mem.out \
   $(objpfx)tst-printf-bz18872-mem.out \
   $(objpfx)tst-printf-bz25691-mem.out \
   $(objpfx)tst-printf-fp-free-mem.out \
@@ -322,6 +326,10 @@ tests-special += \
   # tests-special
 
 generated += \
+  tst-getline-enomem-mem.out \
+  tst-getline-enomem.mtrace \
+  tst-getline-mem.out \
+  tst-getline.mtrace \
   tst-printf-bz18872-mem.out \
   tst-printf-bz18872.c \
   tst-printf-bz18872.mtrace \
@@ -431,6 +439,12 @@ tst-scanf-bz27650-ENV = \
 tst-ungetc-leak-ENV = \
   MALLOC_TRACE=$(objpfx)tst-ungetc-leak.mtrace \
   LD_PRELOAD=$(common-objpfx)malloc/libc_malloc_debug.so
+tst-getline-ENV = \
+  MALLOC_TRACE=$(objpfx)tst-getline.mtrace \
+  LD_PRELOAD=$(common-objpfx)malloc/libc_malloc_debug.so
+tst-getline-enomem-ENV = \
+  MALLOC_TRACE=$(objpfx)tst-getline-enomem.mtrace \
+  LD_PRELOAD=$(common-objpfx)malloc/libc_malloc_debug.so
 
 $(objpfx)tst-unbputc.out: tst-unbputc.sh $(objpfx)tst-unbputc
        $(SHELL) $< $(common-objpfx) '$(test-program-prefix)'; \

diff --git a/stdio-common/tst-getline-enomem.c b/stdio-common/tst-getline-enomem.c
new file mode 100644 (file)
index 0000000..7fc70ea
--- /dev/null
+++ b/stdio-common/tst-getline-enomem.c
@@ -0,0 +1,78 @@
+/* Test getline: ENOMEM on allocation failure.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <mcheck.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/resource.h>
+
+#include <support/check.h>
+#include <support/test-driver.h>
+
+/* Produce a stream of test data based on data in COOKIE (ignored),
+   storing up to SIZE bytes in BUF.  */
+
+static ssize_t
+io_read (void *cookie, char *buf, size_t size)
+{
+  memset (buf, 'x', size);
+  return size;
+}
+
+/* Set up a test stream with fopencookie.  */
+
+static FILE *
+open_test_stream (void)
+{
+  static cookie_io_functions_t io_funcs = { .read = io_read };
+  static int cookie;
+  FILE *fp = fopencookie (&cookie, "r", io_funcs);
+  TEST_VERIFY_EXIT (fp != NULL);
+  return fp;
+}
+
+int
+do_test (void)
+{
+  FILE *fp;
+  char *lineptr = NULL;
+  size_t size = 0;
+  ssize_t ret;
+  mtrace ();
+  /* Test ENOMEM (and error indicator for stream set) for memory
+     allocation failure.  */
+  verbose_printf ("Testing memory allocation failure\n");
+  fp = open_test_stream ();
+  struct rlimit limit;
+  TEST_VERIFY_EXIT (getrlimit (RLIMIT_AS, &limit) == 0);
+  limit.rlim_cur = 32 * 1024 * 1024;
+  TEST_VERIFY_EXIT (setrlimit (RLIMIT_AS, &limit) == 0);
+  errno = 0;
+  ret = getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (errno, ENOMEM);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  free (lineptr);
+  fclose (fp);
+  return 0;
+}
+
+#include <support/test-driver.c>

diff --git a/stdio-common/tst-getline.c b/stdio-common/tst-getline.c
new file mode 100644 (file)
index 0000000..29eb7ce
--- /dev/null
+++ b/stdio-common/tst-getline.c
@@ -0,0 +1,451 @@
+/* Test getline.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <malloc.h>
+#include <mcheck.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <support/check.h>
+#include <support/test-driver.h>
+#include <support/support.h>
+#include <support/xstdio.h>
+#include <support/xunistd.h>
+
+static struct test_data
+{
+  /* Input test data for fopencookie stream.  */
+  const char *in_data;
+
+  /* The amount of test data left.  */
+  size_t in_data_left;
+
+  /* Error number for forcing an error on next read.  */
+  int in_error;
+
+  /* Error number for forcing an error (rather than EOF) after all
+     bytes read.  */
+  int in_error_after;
+} the_cookie;
+
+/* Produce a stream of test data based on data in COOKIE, storing up
+   to SIZE bytes in BUF.  */
+
+static ssize_t
+io_read (void *cookie, char *buf, size_t size)
+{
+  struct test_data *p = cookie;
+  if (p->in_error)
+    {
+      errno = p->in_error;
+      return -1;
+    }
+  if (size > p->in_data_left)
+    size = p->in_data_left;
+  memcpy (buf, p->in_data, size);
+  p->in_data += size;
+  p->in_data_left -= size;
+  if (p->in_data_left == 0)
+    p->in_error = p->in_error_after;
+  return size;
+}
+
+/* Set up a test stream with fopencookie.  */
+
+static FILE *
+open_test_stream (const char *in_data, size_t size)
+{
+  static cookie_io_functions_t io_funcs = { .read = io_read };
+  the_cookie.in_data = in_data;
+  the_cookie.in_data_left = size;
+  the_cookie.in_error = 0;
+  the_cookie.in_error_after = 0;
+  FILE *fp = fopencookie (&the_cookie, "r", io_funcs);
+  TEST_VERIFY_EXIT (fp != NULL);
+  return fp;
+}
+
+/* Set up a test stream with fopencookie, using data from a string
+   literal.  */
+#define OPEN_TEST_STREAM(IN_DATA) open_test_stream (IN_DATA, sizeof (IN_DATA))
+
+/* Wrap getline to verify that (as per the glibc manual), *LINEPTR is
+   returned as non-null and with at least *N bytes (even on error or
+   EOF).  Also clear errno for the benefit of tests that check the
+   value of errno after the call.  */
+
+ssize_t
+wrap_getline (char **lineptr, size_t *n, FILE *stream)
+{
+  errno = 0;
+  ssize_t ret = getline (lineptr, n, stream);
+  if (lineptr != NULL && n != NULL)
+    {
+      TEST_VERIFY (*lineptr != NULL);
+      TEST_VERIFY (malloc_usable_size (*lineptr) >= *n);
+    }
+  return ret;
+}
+
+int
+do_test (void)
+{
+  FILE *fp;
+  char *lineptr = NULL;
+  size_t size = 0;
+  ssize_t ret;
+  mtrace ();
+  /* Test failure with EINVAL (and error indicator for stream set) if
+     lineptr is a null pointer.  */
+  verbose_printf ("Testing lineptr == NULL\n");
+  fp = OPEN_TEST_STREAM ("test");
+  ret = wrap_getline (NULL, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (errno, EINVAL);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  fclose (fp);
+  /* Test failure with EINVAL (and error indicator for stream set) if
+     n is a null pointer.  */
+  verbose_printf ("Testing n == NULL\n");
+  fp = OPEN_TEST_STREAM ("test");
+  ret = wrap_getline (&lineptr, NULL, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (errno, EINVAL);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  fclose (fp);
+  /* Test failure with EINVAL (and error indicator for stream set) if
+     both lineptr and n are null pointers.  */
+  verbose_printf ("Testing lineptr == NULL and n == NULL\n");
+  fp = OPEN_TEST_STREAM ("test");
+  ret = wrap_getline (NULL, NULL, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (errno, EINVAL);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  fclose (fp);
+  /* Test normal line, fitting in available space (including case with
+     null bytes).  */
+  verbose_printf ("Testing normal nonempty input\n");
+  lineptr = xmalloc (10);
+  size = 10;
+  fp = OPEN_TEST_STREAM ("foo\nbar\0\n\0baz\nte\0st\n");
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 4);
+  TEST_COMPARE_BLOB (lineptr, 5, "foo\n", 5);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 5);
+  TEST_COMPARE_BLOB (lineptr, 6, "bar\0\n", 6);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 5);
+  TEST_COMPARE_BLOB (lineptr, 6, "\0baz\n", 6);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 6);
+  TEST_COMPARE_BLOB (lineptr, 7, "te\0st\n", 7);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 1);
+  TEST_COMPARE_BLOB (lineptr, 1, "", 1);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (ferror (fp), 0);
+  TEST_COMPARE (!!feof (fp), 1);
+  fclose (fp);
+  /* Test normal line, with reallocation (including case with null bytes).  */
+  verbose_printf ("Testing normal nonempty input with reallocation\n");
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  fp = OPEN_TEST_STREAM ("foo\nbar\0\n\0baz\nte\0st\n"
+                        "foo\nbar\0\n\0baz\nte\0st\n");
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 4);
+  TEST_COMPARE_BLOB (lineptr, 5, "foo\n", 5);
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 5);
+  TEST_COMPARE_BLOB (lineptr, 6, "bar\0\n", 6);
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 5);
+  TEST_COMPARE_BLOB (lineptr, 6, "\0baz\n", 6);
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 6);
+  TEST_COMPARE_BLOB (lineptr, 7, "te\0st\n", 7);
+  free (lineptr);
+  lineptr = xmalloc (1);
+  size = 1;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 4);
+  TEST_COMPARE_BLOB (lineptr, 5, "foo\n", 5);
+  free (lineptr);
+  lineptr = xmalloc (1);
+  size = 1;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 5);
+  TEST_COMPARE_BLOB (lineptr, 6, "bar\0\n", 6);
+  free (lineptr);
+  lineptr = xmalloc (1);
+  size = 1;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 5);
+  TEST_COMPARE_BLOB (lineptr, 6, "\0baz\n", 6);
+  free (lineptr);
+  lineptr = xmalloc (1);
+  size = 1;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 6);
+  TEST_COMPARE_BLOB (lineptr, 7, "te\0st\n", 7);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 1);
+  TEST_COMPARE_BLOB (lineptr, 1, "", 1);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (ferror (fp), 0);
+  TEST_COMPARE (!!feof (fp), 1);
+  fclose (fp);
+  /* Test EOF before delimiter but after some bytes read, fitting in
+     available space (including case with null bytes).  */
+  verbose_printf ("Testing EOF before delimiter\n");
+  free (lineptr);
+  lineptr = xmalloc (10);
+  size = 10;
+  fp = open_test_stream ("foo", 3);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 3);
+  TEST_COMPARE_BLOB (lineptr, 4, "foo", 4);
+  fclose (fp);
+  free (lineptr);
+  lineptr = xmalloc (10);
+  size = 10;
+  fp = open_test_stream ("bar\0", 4);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 4);
+  TEST_COMPARE_BLOB (lineptr, 5, "bar\0", 5);
+  fclose (fp);
+  free (lineptr);
+  lineptr = xmalloc (10);
+  size = 10;
+  fp = open_test_stream ("\0baz", 4);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 4);
+  TEST_COMPARE_BLOB (lineptr, 5, "\0baz", 5);
+  fclose (fp);
+  free (lineptr);
+  lineptr = xmalloc (10);
+  size = 10;
+  fp = open_test_stream ("te\0st", 5);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 5);
+  TEST_COMPARE_BLOB (lineptr, 6, "te\0st", 6);
+  fclose (fp);
+  /* Test EOF before delimiter but after some bytes read, with
+     reallocation (including case with null bytes).  */
+  verbose_printf ("Testing EOF before delimiter with reallocation\n");
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  fp = open_test_stream ("foo", 3);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 3);
+  TEST_COMPARE_BLOB (lineptr, 4, "foo", 4);
+  fclose (fp);
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  fp = open_test_stream ("bar\0", 4);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 4);
+  TEST_COMPARE_BLOB (lineptr, 5, "bar\0", 5);
+  fclose (fp);
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  fp = open_test_stream ("\0baz", 4);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 4);
+  TEST_COMPARE_BLOB (lineptr, 5, "\0baz", 5);
+  fclose (fp);
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  fp = open_test_stream ("te\0st", 5);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 5);
+  TEST_COMPARE_BLOB (lineptr, 6, "te\0st", 6);
+  fclose (fp);
+  free (lineptr);
+  lineptr = xmalloc (1);
+  size = 1;
+  fp = open_test_stream ("foo", 3);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 3);
+  TEST_COMPARE_BLOB (lineptr, 4, "foo", 4);
+  fclose (fp);
+  free (lineptr);
+  lineptr = xmalloc (1);
+  size = 1;
+  fp = open_test_stream ("bar\0", 4);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 4);
+  TEST_COMPARE_BLOB (lineptr, 5, "bar\0", 5);
+  fclose (fp);
+  free (lineptr);
+  lineptr = xmalloc (1);
+  size = 1;
+  fp = open_test_stream ("\0baz", 4);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 4);
+  TEST_COMPARE_BLOB (lineptr, 5, "\0baz", 5);
+  fclose (fp);
+  free (lineptr);
+  lineptr = xmalloc (1);
+  size = 1;
+  fp = open_test_stream ("te\0st", 5);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 5);
+  TEST_COMPARE_BLOB (lineptr, 6, "te\0st", 6);
+  fclose (fp);
+  /* Test EOF with no bytes read (nothing is specified about anything
+     written to the buffer), including EOF again when already at end
+     of file.  */
+  verbose_printf ("Testing EOF with no bytes read\n");
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  fp = open_test_stream ("", 0);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (ferror (fp), 0);
+  TEST_COMPARE (!!feof (fp), 1);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (ferror (fp), 0);
+  TEST_COMPARE (!!feof (fp), 1);
+  fclose (fp);
+  free (lineptr);
+  lineptr = xmalloc (1);
+  size = 1;
+  fp = open_test_stream ("", 0);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (ferror (fp), 0);
+  TEST_COMPARE (!!feof (fp), 1);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (ferror (fp), 0);
+  TEST_COMPARE (!!feof (fp), 1);
+  fclose (fp);
+  /* Test error occurring with no bytes read, including calling
+     wrap_getline again while the file is in error state.  */
+  verbose_printf ("Testing error with no bytes read\n");
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  fp = open_test_stream ("", 0);
+  the_cookie.in_error = EINVAL;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (errno, EINVAL);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  /* Make sure error state is sticky.  */
+  the_cookie.in_error = 0;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  fclose (fp);
+  /* Test error occurring after some bytes read.  Specifications are
+     ambiguous here; at least in the fopencookie case used for
+     testing, glibc returns the partial line (but with the error
+     indicator on the stream set).  */
+  verbose_printf ("Testing error after some bytes read\n");
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  fp = open_test_stream ("foo", 3);
+  the_cookie.in_error_after = EINVAL;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, 3);
+  TEST_COMPARE_BLOB (lineptr, 4, "foo", 4);
+  TEST_COMPARE (errno, EINVAL);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  /* Make sure error state is sticky.  */
+  the_cookie.in_error = 0;
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  fclose (fp);
+  /* Test EBADF error as a representative example of an fgetc error
+     resulting in an error from wrap_getline.  We don't try to cover all
+     error cases for fgetc here.  */
+  verbose_printf ("Testing EBADF error\n");
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  fp = xfopen ("/dev/null", "r");
+  xclose (fileno (fp));
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (errno, EBADF);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  fclose (fp);
+  /* Test EAGAIN error as an example of an fgetc error on a valid file
+     descriptor.  */
+  verbose_printf ("Testing EAGAIN error\n");
+  free (lineptr);
+  lineptr = NULL;
+  size = 0;
+  int pipefd[2];
+  xpipe (pipefd);
+  ret = fcntl (pipefd[0], F_SETFL, O_NONBLOCK);
+  TEST_VERIFY_EXIT (ret == 0);
+  fp = fdopen (pipefd[0], "r");
+  TEST_VERIFY_EXIT (fp != NULL);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (errno, EAGAIN);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  /* Make sure error state is sticky (even after more data is
+     available to read).  */
+  xwrite (pipefd[1], "x\n", 2);
+  ret = wrap_getline (&lineptr, &size, fp);
+  TEST_COMPARE (ret, -1);
+  TEST_COMPARE (!!ferror (fp), 1);
+  TEST_COMPARE (feof (fp), 0);
+  fclose (fp);
+  free (lineptr);
+  return 0;
+}
+
+#include <support/test-driver.c>