Deprecate the use of regexp.h

<regexp.h> (not to be confused with <regex.h>) is an obsolete and
frankly horrible regular expression-matching API.  It was part of SVID
but was withdrawn in Issue 5 (for reference, we're on Issue 7 now).
It doesn't do anything you can't do with <regex.h>, and using it
involves defining a bunch of macros before including the header.
Moreover, the code in regexp.h that uses those macros has been buggy
since its creation (in 1996) and no one has noticed, which indicates
to me that there are no users.  (Specifically, RETURN() is used in a
whole bunch of cases where it should have been ERROR().)

The header is given a warning and marked deprecated for 2.22.

See:
https://sourceware.org/ml/libc-alpha/2015-07/msg00862.html and
https://sourceware.org/ml/libc-alpha/2015-07/msg00871.html.
This commit is contained in:
Zack Weinberg 2015-08-01 14:38:05 -04:00 committed by Carlos O'Donell
parent f4ddb3557e
commit 2ec11c2b6e
4 changed files with 39 additions and 18 deletions

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@ -1,3 +1,13 @@
2015-07-31 Zack Weinberg <zackw@panix.com>
[BZ #18681]
* regexp.h: Add unconditional #warning stating that this header
will be removed soon. Revise banner comment to match.
(compile): Consistently use ERROR instead of RETURN to report
errors (partial fix for bz#18681).
* regexp.c: Don't include regexp.h. Remove some unnecessary
declarations.
2015-07-31 Carlos O'Donell <carlos@redhat.com>
* po/libc.pot: Regenerated.

8
NEWS
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@ -79,6 +79,14 @@ Version 2.22
* Port to Native Client running on ARMv7-A (--host=arm-nacl).
Contributed by Roland McGrath (Google).
* The header <regexp.h> is deprecated, and will be removed in a future
release. Use of this header will trigger a deprecation warning.
Application developers should update their code to use <regex.h> instead.
This header was formerly part of SUSv2, but was deprecated in 1997 and
removed from the standard in 2001. Also, the glibc implementation
leaks memory. See BZ#18681 for more details.
Version 2.21

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@ -17,8 +17,10 @@
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#define __DO_NOT_DEFINE_COMPILE
#include <regexp.h>
/* We don't include regexp.h here because of the macros it requires, and
because it now contains an unconditional #warning. */
#include <regex.h>
/* Define the variables used for the interface. */
char *loc1;
@ -32,7 +34,6 @@ char *locs;
found in the buffer starting at EXPBUF. `loc1' will return the
first character matched and `loc2' points to the next unmatched
character. */
extern int __step (const char *string, const char *expbuf);
int
__step (const char *string, const char *expbuf)
{
@ -55,7 +56,6 @@ weak_alias (__step, step)
/* Match the beginning of STRING with the compiled regular expression
in EXPBUF. If the match is successful `loc2' will contain the
position of the first unmatched character. */
extern int __advance (const char *string, const char *expbuf);
int
__advance (const char *string, const char *expbuf)
{

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@ -19,14 +19,17 @@
#ifndef _REGEXP_H
#define _REGEXP_H 1
/* The contents of this header file was first standardized in X/Open
System Interface and Headers Issue 2, originally coming from SysV.
In issue 4, version 2, it is marked as TO BE WITDRAWN, and it has
been withdrawn in SUSv3.
/* The contents of this header file were standardized in the
Single Unix Specification, Version 2 (1997) but marked as
LEGACY; new applications were already being encouraged to
use <regex.h> instead. POSIX.1-2001 removed this header.
This code shouldn't be used in any newly written code. It is
included only for compatibility reasons. Use the POSIX definition
in <regex.h> for portable applications and a reasonable interface. */
This header is provided only for backward compatibility.
It will be removed in the next release of the GNU C Library.
New code should use <regex.h> instead. */
#warning "<regexp.h> will be removed in the next release of the GNU C Library."
#warning "Please update your code to use <regex.h> instead (no trailing 'p')."
#include <features.h>
#include <alloca.h>
@ -182,19 +185,19 @@ compile (char *__restrict instring, char *__restrict expbuf,
case REG_ERPAREN:
default:
/* There is no matching error code. */
RETURN (36);
ERROR (36);
case REG_ESUBREG:
RETURN (25);
ERROR (25);
case REG_EBRACK:
RETURN (49);
ERROR (49);
case REG_EPAREN:
RETURN (42);
ERROR (42);
case REG_EBRACE:
RETURN (44);
ERROR (44);
case REG_BADBR:
RETURN (46);
ERROR (46);
case REG_ERANGE:
RETURN (11);
ERROR (11);
case REG_ESPACE:
case REG_ESIZE:
ERROR (50);