diff mbox series

[11/11] libio: Remove __libc_readline_unlocked

Message ID 91d2c5c779a35a7b27ce9433aca28c5b6d452a3b.1594974444.git.fweimer@redhat.com
State New
Headers show
Series Fix fgetsgent_r data corruption bug (20338) | expand

Commit Message

Florian Weimer July 17, 2020, 8:31 a.m. UTC
__nss_readline supersedes it.  This reverts part of commit
3f5e3f5d066dcffb80af48ae2cf35a01a85a8f10 ("libio: Implement
internal function __libc_readline_unlocked").  The internal
aliases __fseeko64 and __ftello64 are preserved because
they are needed by __nss_readline as well.
---
 include/stdio.h      |  13 ---
 libio/Makefile       |   4 +-
 libio/Versions       |   1 -
 libio/readline.c     | 170 -------------------------------
 libio/tst-readline.c | 237 -------------------------------------------
 5 files changed, 2 insertions(+), 423 deletions(-)
 delete mode 100644 libio/readline.c
 delete mode 100644 libio/tst-readline.c

Comments

Carlos O'Donell July 21, 2020, 3:28 a.m. UTC | #1
On 7/17/20 4:31 AM, Florian Weimer via Libc-alpha wrote:
> __nss_readline supersedes it.  This reverts part of commit
> 3f5e3f5d066dcffb80af48ae2cf35a01a85a8f10 ("libio: Implement
> internal function __libc_readline_unlocked").  The internal
> aliases __fseeko64 and __ftello64 are preserved because
> they are needed by __nss_readline as well.

OK for 2.32.

Yes, __nss_readline supersedes __libc_readline_unlocked, and
you have used __nss_readline to fix a number of consistency
issues (and bug 20338), so we know semantically it's a better
fit. The alternative would have been to improve __libc_readline_unlocked
but it's less specialized and so would have required more boiler-plate
per use and I like the cleanup that the slightly more specialized
__nss_readline provides.

Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>

> ---
>  include/stdio.h      |  13 ---
>  libio/Makefile       |   4 +-
>  libio/Versions       |   1 -
>  libio/readline.c     | 170 -------------------------------
>  libio/tst-readline.c | 237 -------------------------------------------
>  5 files changed, 2 insertions(+), 423 deletions(-)
>  delete mode 100644 libio/readline.c
>  delete mode 100644 libio/tst-readline.c
> 
> diff --git a/include/stdio.h b/include/stdio.h
> index ede0f3d444..2e0dc80c16 100644
> --- a/include/stdio.h
> +++ b/include/stdio.h
> @@ -179,19 +179,6 @@ int __vfxprintf (FILE *__fp, const char *__fmt, __gnuc_va_list,
>  		 unsigned int)
>    attribute_hidden;
>  
> -/* Read the next line from FP into BUFFER, of LENGTH bytes.  LINE will
> -   include the line terminator and a NUL terminator.  On success,
> -   return the length of the line, including the line terminator, but
> -   excluding the NUL termintor.  On EOF, return zero and write a NUL
> -   terminator.  On error, return -1 and set errno.  If the total byte
> -   count (line and both terminators) exceeds LENGTH, return -1 and set
> -   errno to ERANGE (but do not mark the stream as failed).
> -
> -   The behavior is undefined if FP is not seekable, or if the stream
> -   is already in an error state.  */
> -ssize_t __libc_readline_unlocked (FILE *fp, char *buffer, size_t length);
> -libc_hidden_proto (__libc_readline_unlocked);

OK.

> -
>  extern const char *const _sys_errlist_internal[] attribute_hidden;
>  extern const char *__get_errlist (int) attribute_hidden;
>  extern const char *__get_errname (int) attribute_hidden;
> diff --git a/libio/Makefile b/libio/Makefile
> index 926df1870b..4f0f777bbb 100644
> --- a/libio/Makefile
> +++ b/libio/Makefile
> @@ -49,7 +49,7 @@ routines	:=							      \
>  	__fbufsize __freading __fwriting __freadable __fwritable __flbf	      \
>  	__fpurge __fpending __fsetlocking				      \
>  									      \
> -	libc_fatal fmemopen oldfmemopen vtables readline
> +	libc_fatal fmemopen oldfmemopen vtables

OK.

>  
>  tests = tst_swprintf tst_wprintf tst_swscanf tst_wscanf tst_getwc tst_putwc   \
>  	tst_wprintf2 tst-widetext test-fmemopen tst-ext tst-ext2 \
> @@ -68,7 +68,7 @@ tests = tst_swprintf tst_wprintf tst_swscanf tst_wscanf tst_getwc tst_putwc   \
>  	tst-sprintf-ub tst-sprintf-chk-ub tst-bz24051 tst-bz24153 \
>  	tst-wfile-sync
>  
> -tests-internal = tst-vtables tst-vtables-interposed tst-readline
> +tests-internal = tst-vtables tst-vtables-interposed
>  

OK.

>  ifeq (yes,$(build-shared))
>  # Add test-fopenloc only if shared library is enabled since it depends on
> diff --git a/libio/Versions b/libio/Versions
> index acb896afa9..6f1ab96100 100644
> --- a/libio/Versions
> +++ b/libio/Versions
> @@ -161,6 +161,5 @@ libc {
>  
>      __fseeko64;
>      __ftello64;
> -    __libc_readline_unlocked;

OK.

>    }
>  }
> diff --git a/libio/readline.c b/libio/readline.c
> deleted file mode 100644
> index 99fecc5825..0000000000
> --- a/libio/readline.c
> +++ /dev/null
> @@ -1,170 +0,0 @@
> -/* fgets with ERANGE error reporting and size_t buffer length.
> -   Copyright (C) 2018-2020 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 <assert.h>
> -#include <errno.h>
> -#include <stdio.h>
> -#include <string.h>
> -
> -#include "libioP.h"
> -
> -/* Return -1 and set errno to EINVAL if it is ERANGE.  */
> -static ssize_t
> -fail_no_erange (void)
> -{
> -  if (errno == ERANGE)
> -    __set_errno (EINVAL);
> -  return -1;
> -}
> -
> -/* Slow path for reading the line.  Called with no data in the stream
> -   read buffer.  Write data to [BUFFER, BUFFER_END).  */
> -static ssize_t
> -readline_slow (FILE *fp, char *buffer, char *buffer_end)
> -{
> -  char *start = buffer;
> -
> -  while (buffer < buffer_end)
> -    {
> -      if (__underflow (fp) == EOF)
> -        {
> -          if (_IO_ferror_unlocked (fp))
> -            /* If the EOF was caused by a read error, report it.  */
> -            return fail_no_erange ();
> -          *buffer = '\0';
> -          /* Do not include the null terminator.  */
> -          return buffer - start;
> -        }
> -
> -      /* __underflow has filled the buffer.  */
> -      char *readptr = fp->_IO_read_ptr;
> -      ssize_t readlen = fp->_IO_read_end - readptr;
> -      /* Make sure that __underflow really has acquired some data.  */
> -      assert (readlen > 0);
> -      char *pnl = memchr (readptr, '\n', readlen);
> -      if (pnl != NULL)
> -        {
> -          /* We found the terminator.  */
> -          size_t line_length = pnl - readptr;
> -          if (line_length + 2 > buffer_end - buffer)
> -            /* Not enough room in the caller-supplied buffer.  */
> -            break;
> -          memcpy (buffer, readptr, line_length + 1);
> -          buffer[line_length + 1] = '\0';
> -          fp->_IO_read_ptr = pnl + 1;
> -          /* Do not include the null terminator.  */
> -          return buffer - start + line_length + 1;
> -        }
> -
> -      if (readlen >= buffer_end - buffer)
> -        /* Not enough room in the caller-supplied buffer.  */
> -        break;
> -
> -      /* Save and consume the stream buffer.  */
> -      memcpy (buffer, readptr, readlen);
> -      fp->_IO_read_ptr = fp->_IO_read_end;
> -      buffer += readlen;
> -    }
> -
> -  /* The line does not fit into the buffer.  */
> -  __set_errno (ERANGE);
> -  return -1;
> -}
> -
> -ssize_t
> -__libc_readline_unlocked (FILE *fp, char *buffer, size_t buffer_length)
> -{
> -  char *buffer_end = buffer + buffer_length;
> -
> -  /* Orient the stream.  */
> -  if (__builtin_expect (fp->_mode, -1) == 0)
> -    _IO_fwide (fp, -1);
> -
> -  /* Fast path: The line terminator is found in the buffer.  */
> -  char *readptr = fp->_IO_read_ptr;
> -  ssize_t readlen = fp->_IO_read_end - readptr;
> -  off64_t start_offset;         /* File offset before reading anything.  */
> -  if (readlen > 0)
> -    {
> -      char *pnl = memchr (readptr, '\n', readlen);
> -      if (pnl != NULL)
> -        {
> -          size_t line_length = pnl - readptr;
> -          /* Account for line and null terminators.  */
> -          if (line_length + 2 > buffer_length)
> -            {
> -              __set_errno (ERANGE);
> -              return -1;
> -            }
> -          memcpy (buffer, readptr, line_length + 1);
> -          buffer[line_length + 1] = '\0';
> -          /* Consume the entire line.  */
> -          fp->_IO_read_ptr = pnl + 1;
> -          return line_length + 1;
> -        }
> -
> -      /* If the buffer does not have enough space for what is pending
> -         in the stream (plus a NUL terminator), the buffer is too
> -         small.  */
> -      if (readlen + 1 > buffer_length)
> -        {
> -          __set_errno (ERANGE);
> -          return -1;
> -        }
> -
> -      /* End of line not found.  We need all the buffered data.  Fall
> -         through to the slow path.  */
> -      memcpy (buffer, readptr, readlen);
> -      buffer += readlen;
> -      /* The original length is invalid after this point.  Use
> -         buffer_end instead.  */
> -#pragma GCC poison buffer_length
> -      /* Read the old offset before updating the read pointer.  */
> -      start_offset = __ftello64 (fp);
> -      fp->_IO_read_ptr = fp->_IO_read_end;
> -    }
> -  else
> -    {
> -      readlen = 0;
> -      start_offset = __ftello64 (fp);
> -    }
> -
> -  /* Slow path: Read more data from the underlying file.  We need to
> -     restore the file pointer if the buffer is too small.  First,
> -     check if the __ftello64 call above failed.  */
> -  if (start_offset < 0)
> -    return fail_no_erange ();
> -
> -  ssize_t result = readline_slow (fp, buffer, buffer_end);
> -  if (result < 0)
> -    {
> -      if (errno == ERANGE)
> -        {
> -          /* Restore the file pointer so that the caller may read the
> -             same line again.  */
> -          if (__fseeko64 (fp, start_offset, SEEK_SET) < 0)
> -            return fail_no_erange ();
> -          __set_errno (ERANGE);
> -        }
> -      /* Do not restore the file position on other errors; it is
> -         likely that the __fseeko64 call would fail, too.  */
> -      return -1;
> -    }
> -  return readlen + result;
> -}
> -libc_hidden_def (__libc_readline_unlocked)
> diff --git a/libio/tst-readline.c b/libio/tst-readline.c
> deleted file mode 100644
> index 40663ed77f..0000000000
> --- a/libio/tst-readline.c
> +++ /dev/null
> @@ -1,237 +0,0 @@
> -/* Test the __libc_readline_unlocked function.
> -   Copyright (C) 2018-2020 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/>.  */
> -
> -/* Exercise __libc_readline_unlocked with various combinations of line
> -   lengths, stdio buffer sizes, and line read buffer sizes.  */
> -
> -#include <errno.h>
> -#include <stdbool.h>
> -#include <stdio.h>
> -#include <string.h>
> -#include <support/check.h>
> -#include <support/support.h>
> -#include <support/temp_file.h>
> -#include <support/test-driver.h>
> -#include <support/xmemstream.h>
> -#include <support/xstdio.h>
> -#include <support/xunistd.h>
> -
> -enum
> -  {
> -    maximum_line_length = 7,
> -    number_of_lines = 3,
> -  };
> -
> -/* -1: Do not set buffer size.  0: unbuffered.  Otherwise, use this as
> -   the size of the buffer.  */
> -static int buffer_size;
> -
> -/* These size of the buffer used for reading.  Must be at least 2.  */
> -static int read_size;
> -
> -/* If a read files with ERANGE, increase the buffer size by this
> -   amount.  Must be positive.  */
> -static int read_size_increment;
> -
> -/* If non-zero, do not reset the read size after an ERANGE error.  */
> -static int read_size_preserve;
> -
> -/* If non-zero, no '\n' at the end of the file.  */
> -static int no_newline_at_eof;
> -
> -/* Length of the line, or -1 if the line is not present.  */
> -static int line_lengths[number_of_lines];
> -
> -/* The name of the test file.  */
> -static char *test_file_path;
> -
> -/* The contents of the test file.  */
> -static char expected_contents[(maximum_line_length + 2) * number_of_lines + 1];
> -static size_t expected_length;
> -
> -/* Returns a random byte which is not zero or the line terminator.  */
> -static char
> -random_char (void)
> -{
> -  static unsigned int rand_state = 1;
> -  while (true)
> -    {
> -      char result = rand_r (&rand_state) >> 16;
> -      if (result != 0 && result != '\n')
> -        return result;
> -    }
> -}
> -
> -/* Create the test file.  */
> -static void
> -prepare (int argc, char **argv)
> -{
> -  int fd = create_temp_file ("tst-readline-", &test_file_path);
> -  TEST_VERIFY_EXIT (fd >= 0);
> -  xclose (fd);
> -}
> -
> -/* Prepare the test file.  Return false if the test parameters are
> -   incongruent and the test should be skipped.  */
> -static bool
> -write_test_file (void)
> -{
> -  expected_length = 0;
> -  char *p = expected_contents;
> -  for (int lineno = 0; lineno < number_of_lines; ++lineno)
> -    for (int i = 0; i < line_lengths[lineno]; ++i)
> -      *p++ = random_char ();
> -  expected_length = p - &expected_contents[0];
> -  if (no_newline_at_eof)
> -    {
> -      if (expected_length == 0)
> -        return false;
> -      --expected_length;
> -      --p;
> -    }
> -  if (test_verbose > 0)
> -    {
> -      printf ("info: writing test file of %zu bytes:\n", expected_length);
> -      for (int i = 0; i < number_of_lines; ++i)
> -        printf (" line %d: %d\n", i, line_lengths[i]);
> -      if (no_newline_at_eof)
> -        puts ("  (no newline at EOF)");
> -    }
> -  TEST_VERIFY_EXIT (expected_length < sizeof (expected_contents));
> -  *p++ = '\0';
> -  support_write_file_string (test_file_path, expected_contents);
> -  return true;
> -}
> -
> -/* Run a single test (a combination of a test file and read
> -   parameters).  */
> -static void
> -run_test (void)
> -{
> -  TEST_VERIFY_EXIT (read_size_increment > 0);
> -  if (test_verbose > 0)
> -    {
> -      printf ("info: running test: buffer_size=%d read_size=%d\n"
> -              "  read_size_increment=%d read_size_preserve=%d\n",
> -              buffer_size, read_size, read_size_increment, read_size_preserve);
> -    }
> -
> -  struct xmemstream result;
> -  xopen_memstream (&result);
> -
> -  FILE *fp = xfopen (test_file_path, "rce");
> -  char *fp_buffer = NULL;
> -  if (buffer_size == 0)
> -    TEST_VERIFY_EXIT (setvbuf (fp, NULL, _IONBF, 0) == 0);
> -  if (buffer_size > 0)
> -    {
> -      fp_buffer = xmalloc (buffer_size);
> -      TEST_VERIFY_EXIT (setvbuf (fp, fp_buffer, _IOFBF, buffer_size) == 0);
> -    }
> -
> -  char *line_buffer = xmalloc (read_size);
> -  size_t line_buffer_size = read_size;
> -
> -  while (true)
> -    {
> -      ssize_t ret = __libc_readline_unlocked
> -        (fp, line_buffer, line_buffer_size);
> -      if (ret < 0)
> -        {
> -          TEST_VERIFY (ret == -1);
> -          if (errno != ERANGE)
> -            FAIL_EXIT1 ("__libc_readline_unlocked: %m");
> -          line_buffer_size += read_size_increment;
> -          free (line_buffer);
> -          line_buffer = xmalloc (line_buffer_size);
> -          /* Try reading this line again.  */
> -        }
> -      else if (ret == 0)
> -        break;
> -      else
> -        {
> -          /* A line has been read.  Save it.  */
> -          TEST_VERIFY (ret == strlen (line_buffer));
> -          const char *pnl = strchr (line_buffer, '\n');
> -          /* If there is a \n, it must be at the end.  */
> -          TEST_VERIFY (pnl == NULL || pnl == line_buffer + ret - 1);
> -          fputs (line_buffer, result.out);
> -
> -          /* Restore the original read size if required.  */
> -          if (line_buffer_size > read_size && !read_size_preserve)
> -            {
> -              line_buffer_size = read_size;
> -              free (line_buffer);
> -              line_buffer = xmalloc (line_buffer_size);
> -            }
> -        }
> -    }
> -
> -  xfclose (fp);
> -  free (fp_buffer);
> -  free (line_buffer);
> -
> -  xfclose_memstream (&result);
> -  TEST_VERIFY (result.length == expected_length);
> -  TEST_VERIFY (strcmp (result.buffer, expected_contents) == 0);
> -  if (test_verbose > 0)
> -    {
> -      printf ("info: expected (%zu): [[%s]]\n",
> -              expected_length, expected_contents);
> -      printf ("info:   actual (%zu): [[%s]]\n", result.length, result.buffer);
> -    }
> -  free (result.buffer);
> -}
> -
> -/* Test one test file with multiple read parameters.  */
> -static void
> -test_one_file (void)
> -{
> -  for (buffer_size = -1; buffer_size <= maximum_line_length + 1; ++buffer_size)
> -    for (read_size = 2; read_size <= maximum_line_length + 2; ++read_size)
> -      for (read_size_increment = 1; read_size_increment <= 4;
> -           ++read_size_increment)
> -        for (read_size_preserve = 0; read_size_preserve < 2;
> -             ++read_size_preserve)
> -          run_test ();
> -}
> -
> -
> -static int
> -do_test (void)
> -{
> -  /* Set up the test file contents.  */
> -  for (line_lengths[0] = -1; line_lengths[0] <= maximum_line_length;
> -       ++line_lengths[0])
> -    for (line_lengths[1] = -1; line_lengths[1] <= maximum_line_length;
> -         ++line_lengths[1])
> -      for (line_lengths[2] = -1; line_lengths[2] <= maximum_line_length;
> -           ++line_lengths[2])
> -        for (no_newline_at_eof = 0; no_newline_at_eof < 2; ++no_newline_at_eof)
> -          {
> -            if (!write_test_file ())
> -              continue;
> -            test_one_file ();
> -          }
> -  free (test_file_path);
> -  return 0;
> -}
> -
> -#define TIMEOUT 100
> -#define PREPARE prepare
> -#include <support/test-driver.c>

OK.

>
diff mbox series

Patch

diff --git a/include/stdio.h b/include/stdio.h
index ede0f3d444..2e0dc80c16 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -179,19 +179,6 @@  int __vfxprintf (FILE *__fp, const char *__fmt, __gnuc_va_list,
 		 unsigned int)
   attribute_hidden;
 
-/* Read the next line from FP into BUFFER, of LENGTH bytes.  LINE will
-   include the line terminator and a NUL terminator.  On success,
-   return the length of the line, including the line terminator, but
-   excluding the NUL termintor.  On EOF, return zero and write a NUL
-   terminator.  On error, return -1 and set errno.  If the total byte
-   count (line and both terminators) exceeds LENGTH, return -1 and set
-   errno to ERANGE (but do not mark the stream as failed).
-
-   The behavior is undefined if FP is not seekable, or if the stream
-   is already in an error state.  */
-ssize_t __libc_readline_unlocked (FILE *fp, char *buffer, size_t length);
-libc_hidden_proto (__libc_readline_unlocked);
-
 extern const char *const _sys_errlist_internal[] attribute_hidden;
 extern const char *__get_errlist (int) attribute_hidden;
 extern const char *__get_errname (int) attribute_hidden;
diff --git a/libio/Makefile b/libio/Makefile
index 926df1870b..4f0f777bbb 100644
--- a/libio/Makefile
+++ b/libio/Makefile
@@ -49,7 +49,7 @@  routines	:=							      \
 	__fbufsize __freading __fwriting __freadable __fwritable __flbf	      \
 	__fpurge __fpending __fsetlocking				      \
 									      \
-	libc_fatal fmemopen oldfmemopen vtables readline
+	libc_fatal fmemopen oldfmemopen vtables
 
 tests = tst_swprintf tst_wprintf tst_swscanf tst_wscanf tst_getwc tst_putwc   \
 	tst_wprintf2 tst-widetext test-fmemopen tst-ext tst-ext2 \
@@ -68,7 +68,7 @@  tests = tst_swprintf tst_wprintf tst_swscanf tst_wscanf tst_getwc tst_putwc   \
 	tst-sprintf-ub tst-sprintf-chk-ub tst-bz24051 tst-bz24153 \
 	tst-wfile-sync
 
-tests-internal = tst-vtables tst-vtables-interposed tst-readline
+tests-internal = tst-vtables tst-vtables-interposed
 
 ifeq (yes,$(build-shared))
 # Add test-fopenloc only if shared library is enabled since it depends on
diff --git a/libio/Versions b/libio/Versions
index acb896afa9..6f1ab96100 100644
--- a/libio/Versions
+++ b/libio/Versions
@@ -161,6 +161,5 @@  libc {
 
     __fseeko64;
     __ftello64;
-    __libc_readline_unlocked;
   }
 }
diff --git a/libio/readline.c b/libio/readline.c
deleted file mode 100644
index 99fecc5825..0000000000
--- a/libio/readline.c
+++ /dev/null
@@ -1,170 +0,0 @@ 
-/* fgets with ERANGE error reporting and size_t buffer length.
-   Copyright (C) 2018-2020 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 <assert.h>
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-
-#include "libioP.h"
-
-/* Return -1 and set errno to EINVAL if it is ERANGE.  */
-static ssize_t
-fail_no_erange (void)
-{
-  if (errno == ERANGE)
-    __set_errno (EINVAL);
-  return -1;
-}
-
-/* Slow path for reading the line.  Called with no data in the stream
-   read buffer.  Write data to [BUFFER, BUFFER_END).  */
-static ssize_t
-readline_slow (FILE *fp, char *buffer, char *buffer_end)
-{
-  char *start = buffer;
-
-  while (buffer < buffer_end)
-    {
-      if (__underflow (fp) == EOF)
-        {
-          if (_IO_ferror_unlocked (fp))
-            /* If the EOF was caused by a read error, report it.  */
-            return fail_no_erange ();
-          *buffer = '\0';
-          /* Do not include the null terminator.  */
-          return buffer - start;
-        }
-
-      /* __underflow has filled the buffer.  */
-      char *readptr = fp->_IO_read_ptr;
-      ssize_t readlen = fp->_IO_read_end - readptr;
-      /* Make sure that __underflow really has acquired some data.  */
-      assert (readlen > 0);
-      char *pnl = memchr (readptr, '\n', readlen);
-      if (pnl != NULL)
-        {
-          /* We found the terminator.  */
-          size_t line_length = pnl - readptr;
-          if (line_length + 2 > buffer_end - buffer)
-            /* Not enough room in the caller-supplied buffer.  */
-            break;
-          memcpy (buffer, readptr, line_length + 1);
-          buffer[line_length + 1] = '\0';
-          fp->_IO_read_ptr = pnl + 1;
-          /* Do not include the null terminator.  */
-          return buffer - start + line_length + 1;
-        }
-
-      if (readlen >= buffer_end - buffer)
-        /* Not enough room in the caller-supplied buffer.  */
-        break;
-
-      /* Save and consume the stream buffer.  */
-      memcpy (buffer, readptr, readlen);
-      fp->_IO_read_ptr = fp->_IO_read_end;
-      buffer += readlen;
-    }
-
-  /* The line does not fit into the buffer.  */
-  __set_errno (ERANGE);
-  return -1;
-}
-
-ssize_t
-__libc_readline_unlocked (FILE *fp, char *buffer, size_t buffer_length)
-{
-  char *buffer_end = buffer + buffer_length;
-
-  /* Orient the stream.  */
-  if (__builtin_expect (fp->_mode, -1) == 0)
-    _IO_fwide (fp, -1);
-
-  /* Fast path: The line terminator is found in the buffer.  */
-  char *readptr = fp->_IO_read_ptr;
-  ssize_t readlen = fp->_IO_read_end - readptr;
-  off64_t start_offset;         /* File offset before reading anything.  */
-  if (readlen > 0)
-    {
-      char *pnl = memchr (readptr, '\n', readlen);
-      if (pnl != NULL)
-        {
-          size_t line_length = pnl - readptr;
-          /* Account for line and null terminators.  */
-          if (line_length + 2 > buffer_length)
-            {
-              __set_errno (ERANGE);
-              return -1;
-            }
-          memcpy (buffer, readptr, line_length + 1);
-          buffer[line_length + 1] = '\0';
-          /* Consume the entire line.  */
-          fp->_IO_read_ptr = pnl + 1;
-          return line_length + 1;
-        }
-
-      /* If the buffer does not have enough space for what is pending
-         in the stream (plus a NUL terminator), the buffer is too
-         small.  */
-      if (readlen + 1 > buffer_length)
-        {
-          __set_errno (ERANGE);
-          return -1;
-        }
-
-      /* End of line not found.  We need all the buffered data.  Fall
-         through to the slow path.  */
-      memcpy (buffer, readptr, readlen);
-      buffer += readlen;
-      /* The original length is invalid after this point.  Use
-         buffer_end instead.  */
-#pragma GCC poison buffer_length
-      /* Read the old offset before updating the read pointer.  */
-      start_offset = __ftello64 (fp);
-      fp->_IO_read_ptr = fp->_IO_read_end;
-    }
-  else
-    {
-      readlen = 0;
-      start_offset = __ftello64 (fp);
-    }
-
-  /* Slow path: Read more data from the underlying file.  We need to
-     restore the file pointer if the buffer is too small.  First,
-     check if the __ftello64 call above failed.  */
-  if (start_offset < 0)
-    return fail_no_erange ();
-
-  ssize_t result = readline_slow (fp, buffer, buffer_end);
-  if (result < 0)
-    {
-      if (errno == ERANGE)
-        {
-          /* Restore the file pointer so that the caller may read the
-             same line again.  */
-          if (__fseeko64 (fp, start_offset, SEEK_SET) < 0)
-            return fail_no_erange ();
-          __set_errno (ERANGE);
-        }
-      /* Do not restore the file position on other errors; it is
-         likely that the __fseeko64 call would fail, too.  */
-      return -1;
-    }
-  return readlen + result;
-}
-libc_hidden_def (__libc_readline_unlocked)
diff --git a/libio/tst-readline.c b/libio/tst-readline.c
deleted file mode 100644
index 40663ed77f..0000000000
--- a/libio/tst-readline.c
+++ /dev/null
@@ -1,237 +0,0 @@ 
-/* Test the __libc_readline_unlocked function.
-   Copyright (C) 2018-2020 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/>.  */
-
-/* Exercise __libc_readline_unlocked with various combinations of line
-   lengths, stdio buffer sizes, and line read buffer sizes.  */
-
-#include <errno.h>
-#include <stdbool.h>
-#include <stdio.h>
-#include <string.h>
-#include <support/check.h>
-#include <support/support.h>
-#include <support/temp_file.h>
-#include <support/test-driver.h>
-#include <support/xmemstream.h>
-#include <support/xstdio.h>
-#include <support/xunistd.h>
-
-enum
-  {
-    maximum_line_length = 7,
-    number_of_lines = 3,
-  };
-
-/* -1: Do not set buffer size.  0: unbuffered.  Otherwise, use this as
-   the size of the buffer.  */
-static int buffer_size;
-
-/* These size of the buffer used for reading.  Must be at least 2.  */
-static int read_size;
-
-/* If a read files with ERANGE, increase the buffer size by this
-   amount.  Must be positive.  */
-static int read_size_increment;
-
-/* If non-zero, do not reset the read size after an ERANGE error.  */
-static int read_size_preserve;
-
-/* If non-zero, no '\n' at the end of the file.  */
-static int no_newline_at_eof;
-
-/* Length of the line, or -1 if the line is not present.  */
-static int line_lengths[number_of_lines];
-
-/* The name of the test file.  */
-static char *test_file_path;
-
-/* The contents of the test file.  */
-static char expected_contents[(maximum_line_length + 2) * number_of_lines + 1];
-static size_t expected_length;
-
-/* Returns a random byte which is not zero or the line terminator.  */
-static char
-random_char (void)
-{
-  static unsigned int rand_state = 1;
-  while (true)
-    {
-      char result = rand_r (&rand_state) >> 16;
-      if (result != 0 && result != '\n')
-        return result;
-    }
-}
-
-/* Create the test file.  */
-static void
-prepare (int argc, char **argv)
-{
-  int fd = create_temp_file ("tst-readline-", &test_file_path);
-  TEST_VERIFY_EXIT (fd >= 0);
-  xclose (fd);
-}
-
-/* Prepare the test file.  Return false if the test parameters are
-   incongruent and the test should be skipped.  */
-static bool
-write_test_file (void)
-{
-  expected_length = 0;
-  char *p = expected_contents;
-  for (int lineno = 0; lineno < number_of_lines; ++lineno)
-    for (int i = 0; i < line_lengths[lineno]; ++i)
-      *p++ = random_char ();
-  expected_length = p - &expected_contents[0];
-  if (no_newline_at_eof)
-    {
-      if (expected_length == 0)
-        return false;
-      --expected_length;
-      --p;
-    }
-  if (test_verbose > 0)
-    {
-      printf ("info: writing test file of %zu bytes:\n", expected_length);
-      for (int i = 0; i < number_of_lines; ++i)
-        printf (" line %d: %d\n", i, line_lengths[i]);
-      if (no_newline_at_eof)
-        puts ("  (no newline at EOF)");
-    }
-  TEST_VERIFY_EXIT (expected_length < sizeof (expected_contents));
-  *p++ = '\0';
-  support_write_file_string (test_file_path, expected_contents);
-  return true;
-}
-
-/* Run a single test (a combination of a test file and read
-   parameters).  */
-static void
-run_test (void)
-{
-  TEST_VERIFY_EXIT (read_size_increment > 0);
-  if (test_verbose > 0)
-    {
-      printf ("info: running test: buffer_size=%d read_size=%d\n"
-              "  read_size_increment=%d read_size_preserve=%d\n",
-              buffer_size, read_size, read_size_increment, read_size_preserve);
-    }
-
-  struct xmemstream result;
-  xopen_memstream (&result);
-
-  FILE *fp = xfopen (test_file_path, "rce");
-  char *fp_buffer = NULL;
-  if (buffer_size == 0)
-    TEST_VERIFY_EXIT (setvbuf (fp, NULL, _IONBF, 0) == 0);
-  if (buffer_size > 0)
-    {
-      fp_buffer = xmalloc (buffer_size);
-      TEST_VERIFY_EXIT (setvbuf (fp, fp_buffer, _IOFBF, buffer_size) == 0);
-    }
-
-  char *line_buffer = xmalloc (read_size);
-  size_t line_buffer_size = read_size;
-
-  while (true)
-    {
-      ssize_t ret = __libc_readline_unlocked
-        (fp, line_buffer, line_buffer_size);
-      if (ret < 0)
-        {
-          TEST_VERIFY (ret == -1);
-          if (errno != ERANGE)
-            FAIL_EXIT1 ("__libc_readline_unlocked: %m");
-          line_buffer_size += read_size_increment;
-          free (line_buffer);
-          line_buffer = xmalloc (line_buffer_size);
-          /* Try reading this line again.  */
-        }
-      else if (ret == 0)
-        break;
-      else
-        {
-          /* A line has been read.  Save it.  */
-          TEST_VERIFY (ret == strlen (line_buffer));
-          const char *pnl = strchr (line_buffer, '\n');
-          /* If there is a \n, it must be at the end.  */
-          TEST_VERIFY (pnl == NULL || pnl == line_buffer + ret - 1);
-          fputs (line_buffer, result.out);
-
-          /* Restore the original read size if required.  */
-          if (line_buffer_size > read_size && !read_size_preserve)
-            {
-              line_buffer_size = read_size;
-              free (line_buffer);
-              line_buffer = xmalloc (line_buffer_size);
-            }
-        }
-    }
-
-  xfclose (fp);
-  free (fp_buffer);
-  free (line_buffer);
-
-  xfclose_memstream (&result);
-  TEST_VERIFY (result.length == expected_length);
-  TEST_VERIFY (strcmp (result.buffer, expected_contents) == 0);
-  if (test_verbose > 0)
-    {
-      printf ("info: expected (%zu): [[%s]]\n",
-              expected_length, expected_contents);
-      printf ("info:   actual (%zu): [[%s]]\n", result.length, result.buffer);
-    }
-  free (result.buffer);
-}
-
-/* Test one test file with multiple read parameters.  */
-static void
-test_one_file (void)
-{
-  for (buffer_size = -1; buffer_size <= maximum_line_length + 1; ++buffer_size)
-    for (read_size = 2; read_size <= maximum_line_length + 2; ++read_size)
-      for (read_size_increment = 1; read_size_increment <= 4;
-           ++read_size_increment)
-        for (read_size_preserve = 0; read_size_preserve < 2;
-             ++read_size_preserve)
-          run_test ();
-}
-
-
-static int
-do_test (void)
-{
-  /* Set up the test file contents.  */
-  for (line_lengths[0] = -1; line_lengths[0] <= maximum_line_length;
-       ++line_lengths[0])
-    for (line_lengths[1] = -1; line_lengths[1] <= maximum_line_length;
-         ++line_lengths[1])
-      for (line_lengths[2] = -1; line_lengths[2] <= maximum_line_length;
-           ++line_lengths[2])
-        for (no_newline_at_eof = 0; no_newline_at_eof < 2; ++no_newline_at_eof)
-          {
-            if (!write_test_file ())
-              continue;
-            test_one_file ();
-          }
-  free (test_file_path);
-  return 0;
-}
-
-#define TIMEOUT 100
-#define PREPARE prepare
-#include <support/test-driver.c>