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[PING] RFC [PATCH] BZ#1077902: New API gettimezone
- From: P J P <pj dot pandit at yahoo dot co dot in>
- To: "libc-alpha at sourceware dot org" <libc-alpha at sourceware dot org>
- Date: Sat, 12 Apr 2014 19:24:44 +0800 (SGT)
- Subject: [PING] RFC [PATCH] BZ#1077902: New API gettimezone
- Authentication-results: sourceware.org; auth=none
- References: <1396499286 dot 85118 dot YahooMailNeo at web192405 dot mail dot sg3 dot yahoo dot com>
- Reply-to: P J P <pj dot pandit at yahoo dot co dot in>
Ping!
> On Thursday, 3 April 2014 10:01 AM, P J P <pj.pandit@yahoo.co.in> wrote:
> Hello,
>
> WRT BZ#1077902 [1], please see the patch below to introduce a new API
> gettimezone(). It builds successfully with the glibc Makefile, though I could
> not test the API from the new library. It uses TZ_VERSION & TZ_FILE macros
> because they aren't defined in timezone/tzfile.h.
>
>
> There is #defines TZDEFAULT "localtime", but that is not sufficient to
> access '/etc/localtime'. There is also #define
> TZDIR /usr/local/etc/zoneinfo, which seems misplaced. On f19 machine, the
> zoneinfo is stored under /usr/share/zoneinfo.
>
> ===
> diff --git a/ChangeLog b/ChangeLog
> index 7e530ef..e2cdbcf 100644
> --- a/ChangeLog
> +++ b/ChangeLog
> @@ -1,3 +1,8 @@
> +2014-04-03 P J P <pj.pandit@yahoo.co.in>
> +
> + [BZ #1077902]
> + * time/gettimezone.c: new API to query POSIX TZ variable string.
> +
> 2014-04-02 Joseph Myers <joseph@codesourcery.com>
>
> [BZ #16799]
> diff --git a/time/Makefile b/time/Makefile
> index b7f3dba..8bcc5ca 100644
> --- a/time/Makefile
> +++ b/time/Makefile
> @@ -31,7 +31,7 @@ routines := offtime asctime clock ctime ctime_r difftime \
> stime dysize timegm ftime \
> getdate strptime strptime_l \
> strftime wcsftime strftime_l wcsftime_l \
> - timespec_get
> + timespec_get gettimezone
> aux := era alt_digit lc-time-cleanup
>
> tests := test_time clocktest tst-posixtz tst-strptime tst_wcsftime \
>
> diff --git a/time/Versions b/time/Versions
> index fd83818..957d2bf 100644
> --- a/time/Versions
> +++ b/time/Versions
> @@ -25,7 +25,7 @@ libc {
> ftime;
>
> # g*
> - getitimer; gettimeofday; gmtime; gmtime_r;
> + getitimer; gettimeofday; gmtime; gmtime_r; gettimezone;
>
> # l*
> localtime; localtime_r;
> diff --git a/time/gettimezone.c b/time/gettimezone.c
> new file mode 100644
> index 0000000..88b2141
> --- /dev/null
> +++ b/time/gettimezone.c
> @@ -0,0 +1,109 @@
> +/* Copyright (C) 1991-2014 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
> + <http://www.gnu.org/licenses/>. */
> +
> +#include <err.h>
> +#include <errno.h>
> +#include <stdio.h>
> +#include <string.h>
> +#include <stdlib.h>
> +#include <sys/stat.h>
> +#include <timezone/tzfile.h>
> +
> +#define TZ_VERSION '2'
> +#define TZ_FILE "/etc/"TZDEFAULT
> +
> +
> +/* gettimezone: reads local timezone definition from '/etc/localtime'
> + and returns a POSIX TZ environment variable string or NULL in case
> + of an error; See: tzfile(5), tzset(3).
> +
> + std offset dst [offset],start[/time],end[/time]
> +
> + Ex: TZ="NZST-12:00:00NZDT-13:00:00,M10.1.0,M3.3.0" */
> +char *
> +gettimezone (const char *tzname)
> +{
> + int n = 0;
> + FILE *fp = NULL;
> + char *tz = NULL, s[4];
> +
> + errno = 0;
> + if (!tzname)
> + tzname = TZ_FILE;
> +
> + fp = fopen (tzname, "rce");
> + if (!fp)
> + return tz;
> +
> + if (fread (s, sizeof (char), 4, fp) != 4)
> + goto err;
> + if (strncmp (TZ_MAGIC, s, 4))
> + goto err;
> +
> + if (fread (s, sizeof (char), 1, fp) != 1)
> + goto err;
> + if (TZ_VERSION != *s && TZ_VERSION != (*s - 1))
> + goto err;
> +
> + if (fseek (fp, -1, SEEK_END) < 0)
> + goto err;
> + if (fread (s, sizeof (char), 1, fp) != 1)
> + goto err;
> + if ('\n' != *s)
> + goto err;
> +
> + n = -2;
> + while (!fseek (fp, n, SEEK_END))
> + {
> + if (fread (s, sizeof (char), 1, fp) != 1)
> + goto err;
> + if ('\n' == *s)
> + break;
> +
> + n--;
> + }
> + fseek (fp, ++n, SEEK_END);
> +
> + n = -(n + 1);
> + tz = calloc (n, sizeof (char));
> + if (!tz)
> + goto err;
> +
> + if (fread (tz, sizeof (char), n, fp) != n)
> + {
> + free (tz);
> + tz = NULL;
> + }
> +
> +err:
> + fclose (fp);
> + return tz;
> +}
> +
> +
> +/* int
> +main (int argc, char *argv[])
> +{
> + char *tz = NULL;
> +
> + tz = gettimezone (NULL);
> + printf ("tz: %s\n", tz);
> + if (tz)
> + free (tz);
> +
> + return 0;
> +} */
> ===
>
>
> --
> [1] https://bugzilla.redhat.com/show_bug.cgi?id=1077902#c2
>
>
> Thank you.
> ---
> Regards
> -Prasad
> http://feedmug.com