[Tarantool-patches] [PATCH resend v2 04/11] lua, datetime: display datetime

[Oleg Babin]

Thanks for your patch. It's not review at all. I have a question:

why is datetime not scalar?


Also I think that encoding and type system changes should live in 
separate patches.


On 28.07.2021 13:34, Timur Safin via Tarantool-patches wrote:
> * introduced output routine for converting datetime
>    to their default output format.
>
> * use this routine for tostring() in datetime.lua
>
> Part of #5941
> ---
>   src/exports.h               |  1 +
>   src/lib/core/CMakeLists.txt |  1 +
>   src/lib/core/datetime.c     | 85 +++++++++++++++++++++++++++++++++++++
>   src/lib/core/datetime.h     | 14 ++++++
>   src/lua/datetime.lua        | 18 ++++++--
>   5 files changed, 116 insertions(+), 3 deletions(-)
>   create mode 100755 src/lib/core/datetime.c
>
> diff --git a/src/exports.h b/src/exports.h
> index db40c03a4..1a03db636 100644
> --- a/src/exports.h
> +++ b/src/exports.h
> @@ -552,3 +552,4 @@ EXPORT(dt_parse_iso_zone_extended)
>   EXPORT(dt_parse_iso_zone_lenient)
>   EXPORT(dt_from_struct_tm)
>   EXPORT(dt_to_struct_tm)
> +EXPORT(datetime_to_string)
> diff --git a/src/lib/core/CMakeLists.txt b/src/lib/core/CMakeLists.txt
> index 2cd4d0b4f..8bc776b82 100644
> --- a/src/lib/core/CMakeLists.txt
> +++ b/src/lib/core/CMakeLists.txt
> @@ -30,6 +30,7 @@ set(core_sources
>       decimal.c
>       mp_decimal.c
>       cord_buf.c
> +    datetime.c
>   )
>   
>   if (TARGET_OS_NETBSD)
> diff --git a/src/lib/core/datetime.c b/src/lib/core/datetime.c
> new file mode 100755
> index 000000000..65f813a70
> --- /dev/null
> +++ b/src/lib/core/datetime.c
> @@ -0,0 +1,85 @@
> +/*
> + * Copyright 2021, Tarantool AUTHORS, please see AUTHORS file.
> + *
> + * Redistribution and use in source and binary forms, with or
> + * without modification, are permitted provided that the following
> + * conditions are met:
> + *
> + * 1. Redistributions of source code must retain the above
> + *    copyright notice, this list of conditions and the
> + *    following disclaimer.
> + *
> + * 2. Redistributions in binary form must reproduce the above
> + *    copyright notice, this list of conditions and the following
> + *    disclaimer in the documentation and/or other materials
> + *    provided with the distribution.
> + *
> + * THIS SOFTWARE IS PROVIDED BY <COPYRIGHT HOLDER> ``AS IS'' AND
> + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
> + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
> + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
> + * <COPYRIGHT HOLDER> OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
> + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
> + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
> + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
> + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
> + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
> + * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
> + * SUCH DAMAGE.
> + */
> +
> +#include <string.h>
> +
> +#include "trivia/util.h"
> +#include "datetime.h"
> +
> +int
> +datetime_to_string(const struct datetime_t * date, char *buf, uint32_t len)
> +{
> +	char * src = buf;
> +	int offset = date->offset;
> +	int64_t secs = date->secs + offset * 60;
> +	dt_t dt = dt_from_rdn((secs / SECS_PER_DAY) + 719163);
> +
> +	int year, month, day, sec, ns, sign;
> +	dt_to_ymd(dt, &year, &month, &day);
> +
> +	int hour = (secs / 3600) % 24,
> +	    minute = (secs / 60) % 60;
> +	;
> +	sec = secs % 60;
> +	ns = date->nsec;
> +	uint32_t sz;
> +	sz = snprintf(buf, len, "%04d-%02d-%02dT%02d:%02d",
> +		      year, month, day, hour, minute);
> +	buf += sz; len -= sz;
> +	if (sec || ns) {
> +		sz = snprintf(buf, len, ":%02d", sec);
> +		buf += sz; len -= sz;
> +		if (ns) {
> +			if ((ns % 1000000) == 0)
> +				sz = snprintf(buf, len, ".%03d", ns / 1000000);
> +			else if ((ns % 1000) == 0)
> +				sz = snprintf(buf, len, ".%06d", ns / 1000);
> +			else
> +				sz = snprintf(buf, len, ".%09d", ns);
> +			buf += sz; len -= sz;
> +		}
> +	}
> +	if (offset == 0) {
> +		strncpy(buf, "Z", len);
> +		buf++;
> +		len--;
> +	}
> +	else {
> +		if (offset < 0)
> +			sign = '-', offset = -offset;
> +		else
> +			sign = '+';
> +
> +		sz = snprintf(buf, len, "%c%02d:%02d", sign, offset / 60, offset % 60);
> +		buf += sz; len -= sz;
> +	}
> +	return (buf - src);
> +}
> diff --git a/src/lib/core/datetime.h b/src/lib/core/datetime.h
> index 403bf1c64..fdaff2d27 100644
> --- a/src/lib/core/datetime.h
> +++ b/src/lib/core/datetime.h
> @@ -38,6 +38,11 @@
>   extern "C" {
>   #endif /* defined(__cplusplus) */
>   
> +#ifndef SECS_PER_DAY
> +#define SECS_PER_DAY	86400
> +#define NANOS_PER_SEC	1000000000
> +#endif
> +
>   /**
>    * datetime structure consisting of:
>    */
> @@ -55,6 +60,15 @@ struct datetime_interval_t {
>   	int32_t nsec; ///< nanoseconds delta
>   };
>   
> +/**
> + * Convert datetime to string using default format
> + * @param date source datetime value
> + * @param buf output character buffer
> + * @param len size ofoutput buffer
> + */
> +int
> +datetime_to_string(const struct datetime_t * date, char *buf, uint32_t len);
> +
>   #if defined(__cplusplus)
>   } /* extern "C" */
>   #endif /* defined(__cplusplus) */
> diff --git a/src/lua/datetime.lua b/src/lua/datetime.lua
> index f4d2d7737..9ec06d8d8 100644
> --- a/src/lua/datetime.lua
> +++ b/src/lua/datetime.lua
> @@ -53,6 +53,12 @@ ffi.cdef [[
>       dt_t    dt_from_struct_tm  (const struct tm *tm);
>       void    dt_to_struct_tm    (dt_t dt, struct tm *tm);
>   
> +    // mp_datetime.c
> +
> +    int
> +    datetime_to_string(const struct datetime_t * date, char *buf, uint32_t len);
> +
> +
>       // <asm-generic/posix_types.h>
>       typedef long            __kernel_long_t;
>       typedef unsigned long   __kernel_ulong_t;
> @@ -549,8 +555,13 @@ local function strftime(fmt, o)
>       return ffi.string(buff)
>   end
>   
> --- strftime may be redirected to datetime:fmt("format")
> -local function datetime_fmt()
> +local function datetime_tostring(o)
> +    assert(ffi.typeof(o) == datetime_t)
> +    local sz = 48
> +    local buff = ffi.new('char[?]', sz)
> +    local len = native.datetime_to_string(o, buff, sz)
> +    assert(len < sz)
> +    return ffi.string(buff)
>   end
>   
>   
> @@ -566,7 +577,8 @@ return setmetatable(
>           parse_date = parse_date,
>           parse_time = parse_time,
>           parse_zone = parse_zone,
> -        fmt = datetime_fmt,
> +
> +        tostring = datetime_tostring,
>   
>           now = local_now,
>       -- strptime = strptime;