[cups-devel] how to get supported media information for a particular printer

[My Sadhukhan]

I could find a way to get the media source via cupsFindDestSupported()
------------
ipp_attribute_t *mediasource = cupsFindDestSupported(http, dest, info,
CUPS_MEDIA_SOURCE);
    count = ippGetCount(mediasource);
    printf("media source count %d %s\n", count, cupsLastErrorString());
    for (int i = 0; i < count; i++) {
        const char *tray = ippGetString(mediasource, i, NULL);
        printf("%s:\n", tray);
        printf("%s:\n", cupsLocalizeDestValue(http, dest, info,
CUPS_MEDIA_SOURCE, tray));
    }
-------
but it gave (ie ippGetString and cupsLocalizeDestValue give same name)
multi-tray:
multi-tray:
1-tray:
1-tray:
2-tray:
2-tray:
3-tray:
3-tray:
4-tray:
4-tray:
5-tray:
5-tray:
auto:
auto:

whereas from ppd, we used to get (where 1st is human-readable name, 2nd is
machine readable name). Is there anyway, we could obtain the same via cups
API?
Bypass Tray
MultiTray
Tray 1
1Tray
Tray 2
2Tray
Tray 3
3Tray
Tray 4
4Tray
Large Capacity Tray
5Tray
Auto Select
Auto

Also, is there any way to find the printer supported resolution (like 600
dpi or 300x300 dpi)?  I tried the following but it gave only
CUPS_PRINT_QUALITY_NORMAL and not a "dpi" value.

    ipp_attribute_t *resolution = cupsFindDestSupported(http, dest, info,
CUPS_PRINT_QUALITY);
    count = ippGetCount(resolution);
    printf("resolution count %d %s\n", count, cupsLastErrorString());
    for (int i = 0; i < count; i++) {
        int quality = ippGetInteger(resolution, i);
        printf("%d:\n", quality);
        //printf("%s:\n", cupsLocalizeDestValue(http, dest, info,
CUPS_PRINT_QUALITY, quality));
    }

On Thu, Oct 5, 2017 at 10:49 AM, My Sadhukhan <psadhukhan at gmail.com> wrote:

>
>
>
> On Thu, Oct 5, 2017 at 5:40 AM, Michael Sweet <msweet at apple.com> wrote:
>
>>
>> > On Oct 4, 2017, at 5:59 AM, My Sadhukhan <psadhukhan at gmail.com> wrote:
>> >
>> > Thanks for the info.
>> > It seems, I need to use CUPS_DEST_FLAGS_NONE for cupsConnectDest()
>> where the connection is made to the CUPS scheduler
>> > and not CUPS_DEST_FLAGS_DEVICE which connect directly to the device
>> associated with the destination (as CUPS_DEST_FLAGS_DEVICE is not supported
>> prior to 2.2.4)
>>
>> Right, connecting to the device is a new feature.
>>
>> > Also, when I use cupsGetDestMediaCount(http, dest, info,
>> CUPS_MEDIA_FLAGS_READY); I was getting "media count" as 0
>>
>> This is because CUPS currently does not track ready media (values are
>> typically stale), which is why CUPS_DEST_FLAGS_DEVICE was added.
>>
>> > and it only works if I specify CUPS_MEDIA_FLAGS_DEFAULT (or
>> CUPS_MEDIA_FLAGS_EXACT) and the obtained media count is 2580 as can be seen
>> here
>> > http://cr.openjdk.java.net/~psadhukhan/cups-media-log.txt
>> >
>> > It seems most of the media information is duplicated around 100 times.
>>
>> That depends on the printer, but basically the full list of media
>> describes all of the different supported combinations of size, source,
>> type, and margins.
>>
>
> I could only get size & margins
> struct cups_size_s {
>     char media[128];
>     int width, length, bottom, left, right, top;
> };
> How to get source & type?
>
>
>> > 1.
>> > Is there anyway we could get unique media size entry?
>>
>> Media information goes well beyond size.  If you want to limit your UI to
>> media sizes only (not recommended!), you'll need to make your own unique
>> list from the full one.
>>
>
> For many media like Letter/A4/A3 etc, we get same localized name via
> cupsLocalizeDestMedia even though margins are different (as seen below)
> whereas via ppd, we used to get
>
> Letter and Letter.FullBleed media names, so if user would like to print in
> borderless letter, there is no way to specify this now via CUPS, is that so?
>
> Letter:
> na_letter_8.5x11in:
>    Width: 8.50in
>    Length: 10.99in
>    Bottom: 0.00in
>    Left: 0.00in
>    Right: 0.00in
>    Top: 0.00in
>
> Letter:
> na_letter_8.5x11in:
>    Width: 8.50in
>    Length: 11.00in
>    Bottom: 0.17in
>    Left: 0.17in
>    Right: 0.17in
>    Top: 0.17in
>
>
>
>
>>
>> >  From ppd file below, I could get that we support around 60 media
>> size(s) [30 normal, 30 fullbleed] so I would expect cups api also would
>> give around 60 media information (and not 2500+)
>>
>> Keep in mind that CUPS is an IPP implementation and exposes the
>> flexibility of IPP wherever possible.  The current use of PPD files is an
>> implementation artifact, and you shouldn't expect CUPS to be limited to
>> what is supported in PPD files.
>>
>> > 2.
>> > By using
>> > ppd_option_t *ppdFindOption("PageSize"); and
>> > then from ppd_option_t*, using ppd_choice_t->text.
>> > we could get the user-understandable media name
>> >
>> > A3  A4  A5 A6  B4 (JIS) B5 (JIS) B6 (JIS)  Legal
>> >  8.25x14 8x10  8x10.5  Letter etc
>> > which normal user can use to specify which media he wants to print
>> >
>> > but from cups api using cups_size_t->media, we are getting
>> > iso_a3_297x420mm
>> > iso_a4_210x297mm
>> > Is there anyway, we can get the same human understandable media name
>> from cups?
>>
>> The cupsLocalizeDestMedia function will give you a human-readable media
>> size name.
>>
>> _________________________________________________________
>> Michael Sweet, Senior Printing System Engineer
>>
>>
>