Re: [sqlite] Using application_id
Pardon the "double post" as it were. I was handily informed the
mailing list strips attachments.
Therefore, for those interested, here's text versions of the header
file (rad50.h) and the actual C that does the RADIX-50 conversions
(rad50.c):
/* == */
#ifndef _RAD50_H
#define _RAD50_H
#include
int rad50enc(const char *, uint16_t *);
int rad50dec(uint16_t, char *);
int xrad50enc(const char *, uint32_t *);
int xrad50dec(uint32_t, char *);
#endif /* _RAD50_H */
/* == */
/*
* Copyright (c) 2019 C. Gauger-Cosgrove
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include
#include
#include "rad50.h"
#define RAD50TAB " ABCDEFGHIJKLMNOPQRSTUVWXYZ$.*0123456789"
int
rad50enc(const char *text, uint16_t *value) {
size_t i;
uint16_t t;
const int mult[3] = {1600, 40, 1};
char *c;
if (strlen(text) == 0) {
*value = 0;
return 0;
} else if (strlen(text) > 3) {
*value = 0x;
return 1;
}
t = 0;
for (i = 0; i < strlen(text); ++i) {
c = (char *) strchr(RAD50TAB, toupper(text[i]));
if (c == NULL) {
*value = 0x;
return 1;
}
t += (c - RAD50TAB) * mult[i];
}
*value = t;
return 0;
}
int
rad50dec(uint16_t value, char *text) {
size_t i;
const int mult[3] = {1600, 40, 1};
if (value >= 0xFA00) {
text[0] = 0;
return 1;
}
for (i = 0; i < 3; ++i)
text[i] = RAD50TAB[(value / mult[i]) % 40];
text[3] = 0;
return 0;
}
int
xrad50enc(const char *text, uint32_t *value) {
size_t i;
uint32_t t;
const int mult[6] = {10240, 256, 64000, 1600, 40, 1};
char *c;
if (strlen(text) == 0) {
*value = 0;
return 0;
} else if (strlen(text) > 6) {
*value = 0x;
return 1;
}
t = 0;
for (i = 0; i < strlen(text); ++i) {
c = (char *) strchr(RAD50TAB, toupper(text[i]));
if (c == NULL) {
*value = 0x;
return 1;
}
t += (c - RAD50TAB) * mult[i];
}
*value = t;
return 0;
}
int
xrad50dec(uint32_t value, char *text) {
size_t i;
const int mult[6] = {10240, 256, 64000, 1600, 40, 1};
if (value >= 0xF424) {
text[0] = 0;
return 1;
}
for (i = 0; i < 6; ++i)
text[i] = RAD50TAB[(value / mult[i]) % 40];
text[6] = 0;
return 0;
}
/* == */
Best regards,
Christian Gauger-Cosgrove
On 19/11/2019, Christian Gauger-Cosgrove wrote:
> On 19/11/2019, Dominique Devienne wrote:
>> On Tue, Nov 19, 2019 at 2:00 AM Peter da Silva wrote:
>>> The return of RADIX-50.
>>>
>>> https://en.wikipedia.org/wiki/DEC_Radix-50
>>
>> Thanks! I might go with this going forward. --DD
>>
> To make life easier for those desiring to experience the Wonders of
> RADIX-50™, if anyone wants I've attached a copy of my implementation
> of RAD50 in both the "traditional" 16-bit form, and a 32-bit form.
>
> The "*enc" functions encode a string into RAD50, and the "*dec"
> functions decode. "rad50*" works on a 16-bit value, "xrad50*" on a
> 32-bit.
>
> I leave it as an exercise for the reader to implement a 64-bit function.
>
> If anyone has ideas of how to improve the functions: Please feel free
> to contribute.
>
> Best regards,
> Christian
> --
> Christian M. Gauger-Co
Re: [sqlite] Using application_id
On 19/11/2019, Dominique Devienne wrote: > On Tue, Nov 19, 2019 at 2:00 AM Peter da Silva wrote: >> The return of RADIX-50. >> >> https://en.wikipedia.org/wiki/DEC_Radix-50 > > Thanks! I might go with this going forward. --DD > To make life easier for those desiring to experience the Wonders of RADIX-50™, if anyone wants I've attached a copy of my implementation of RAD50 in both the "traditional" 16-bit form, and a 32-bit form. The "*enc" functions encode a string into RAD50, and the "*dec" functions decode. "rad50*" works on a 16-bit value, "xrad50*" on a 32-bit. I leave it as an exercise for the reader to implement a 64-bit function. If anyone has ideas of how to improve the functions: Please feel free to contribute. Best regards, Christian -- Christian M. Gauger-Cosgrove STCKON08DS0 Contact information available upon request. ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Using application_id
On Tue, Nov 19, 2019 at 2:00 AM Peter da Silva wrote: > > > If you stick to lower or upper case letters, could encode up to 6 chars > in the app_id. --DD > > The return of RADIX-50. > > https://en.wikipedia.org/wiki/DEC_Radix-50 Thanks! I might go with this going forward. --DD PS: I tend to prefer reusing "old tech" like this, which already has a "known" name, and Wikipedia page, rather that inventing my own similar but poorly-documented-by-comparison scheme. When I'm aware of them that is :) ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Using application_id
> If you stick to lower or upper case letters, could encode up to 6 chars in > the app_id. --DD The return of RADIX-50. https://en.wikipedia.org/wiki/DEC_Radix-50 ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Using application_id
Hi Clemens! Thanks for your fast reply! And/or how can one "register" an application id to prevent collisions? Submit a patch here. In my case, that would be: --- magic.txt.orig 2019-11-18 18:12:00.957789352 +0100 +++ magic.txt 2019-11-18 18:13:13.055463773 +0100 @@ -29,4 +29,7 @@ >68 belong =0x47503130 OGC GeoPackage version 1.0 file - >68 belong =0x45737269 Esri Spatially-Enabled Database - >68 belong =0x4d504258 MBTiles tileset - +>68 belong =0x4d75636b Muckturnier.org tournament database +>>60 belong x\b (Revision %d) - +!:mime application/x-muckturnier >0 string =SQLite SQLite3 database ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Using application_id
On Mon, Nov 18, 2019 at 2:41 PM Clemens Ladisch wrote: > Tobias Leupold wrote: > Apparently, authors or 'private' file formats do not bother to register > their IDs. > Indeed, there's little point, as those are rarely "public". I tend to chose a 4 letter prefix related to the kind of app/report the SQLite DB is for, and use the hexa for each letter to generate the app_id 32-bit integer. If you stick to lower or upper case letters, could encode up to 6 chars in the app_id. --DD ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
Re: [sqlite] Using application_id
Tobias Leupold wrote: > In the docs, a magic file is linked ( https://www.sqlite.org/src/ > artifact?ci=trunk&filename=magic.txt ) with "registered" formats. > > Is there another list with "taken" application ids? No. Apparently, authors or 'private' file formats do not bother to register their IDs. > And/or how can one "register" an application id to prevent collisions? Submit a patch here. Regards, Clemens ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
[sqlite] Using application_id
Hi list! I recently learned about the PRAGMA application_id feature of SQLite, which is really nice to be able to identify an application-specific SQLite database at the file system level, even with versioning support via the user_version header. SQLite encourages to use an SQLite database as one's application file format, which I do for one of my projects (like probably hundreds of other projects do). In the docs, a magic file is linked ( https://www.sqlite.org/src/ artifact?ci=trunk&filename=magic.txt ) with "registered" formats. With SQLite being so widely used, I can hardly believe that only 6 projects decided to make use of the application_id header until now. So here's my question: Is there another list with "taken" application ids? Some kind of wiki perhaps? And/or how can one "register" an application id to prevent collisions? Thanks for the information in advance! Cheers, Tobias ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
