#include "misc.hh"
#include "store-api.hh"
#include "local-store.hh"
#include "globals.hh"


namespace nix {


Derivation derivationFromPath(StoreAPI & store, const Path & drvPath)
{
    assertStorePath(drvPath);
    store.ensurePath(drvPath);
    return readDerivation(drvPath);
}


void computeFSClosure(StoreAPI & store, const Path & path,
    PathSet & paths, bool flipDirection, bool includeOutputs, bool includeDerivers)
{
    if (paths.find(path) != paths.end()) return;
    paths.insert(path);

    PathSet edges;

    if (flipDirection) {
        store.queryReferrers(path, edges);

        if (includeOutputs) {
            PathSet derivers = store.queryValidDerivers(path);
            foreach (PathSet::iterator, i, derivers)
                edges.insert(*i);
        }

        if (includeDerivers && isDerivation(path)) {
            PathSet outputs = store.queryDerivationOutputs(path);
            foreach (PathSet::iterator, i, outputs)
                if (store.isValidPath(*i) && store.queryDeriver(*i) == path)
                    edges.insert(*i);
        }

    } else {
        store.queryReferences(path, edges);

        if (includeOutputs && isDerivation(path)) {
            PathSet outputs = store.queryDerivationOutputs(path);
            foreach (PathSet::iterator, i, outputs)
                if (store.isValidPath(*i)) edges.insert(*i);
        }

        if (includeDerivers) {
            Path deriver = store.queryDeriver(path);
            if (store.isValidPath(deriver)) edges.insert(deriver);
        }
    }

    foreach (PathSet::iterator, i, edges)
        computeFSClosure(store, *i, paths, flipDirection, includeOutputs, includeDerivers);
}


static void dfsVisit(StoreAPI & store, const PathSet & paths,
    const Path & path, PathSet & visited, Paths & sorted,
    PathSet & parents)
{
    if (parents.find(path) != parents.end())
        throw BuildError(format("cycle detected in the references of `%1%'") % path);

    if (visited.find(path) != visited.end()) return;
    visited.insert(path);
    parents.insert(path);

    PathSet references;
    if (store.isValidPath(path))
        store.queryReferences(path, references);

    foreach (PathSet::iterator, i, references)
        /* Don't traverse into paths that don't exist.  That can
           happen due to substitutes for non-existent paths. */
        if (*i != path && paths.find(*i) != paths.end())
            dfsVisit(store, paths, *i, visited, sorted, parents);

    sorted.push_front(path);
    parents.erase(path);
}


Paths topoSortPaths(StoreAPI & store, const PathSet & paths)
{
    Paths sorted;
    PathSet visited, parents;
    foreach (PathSet::const_iterator, i, paths)
        dfsVisit(store, paths, *i, visited, sorted, parents);
    return sorted;
}


}
1-09-21</span></td><td><a href='/guix/commit/gnu/installer/keymap.scm?id=d58e52b0713648dd30d41b41277854a935d8d15a'>installer: keymap: Fix optional fields handling.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes: &lt;https://issues.guix.gnu.org/50723&gt;.

The keymap xml contains optional shortDescription and description fields. The
assoc-ref call on those fields can return false, handle it correctly.

* gnu/installer/keymap.scm (xkb-rules-&gt;models+layouts): Introduce a new
"maybe-empty" helper to deal with optional fields. Use it for shortDescription
and description fields.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-04-09 02:42:54 +0000'>2020-04-09</span></td><td><a href='/guix/commit/gnu/installer/keymap.scm?id=91c231a2223440081426929828a23c7baa0214fd'>installer: Allow Alt+Shift toggle from non-Latin keyboard layouts.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://bugs.gnu.org/40493&gt;.

* gnu/installer/newt/keymap.scm (%non-latin-layouts): New variable.
(%non-latin-variants): New variable.
(%latin-layout+variants): New variable.
(toggleable-latin-layout): New procedure to compute combined layouts.
(run-keymap-page): Use it.
(keyboard-layout-&gt;configuration): Apply it in config.scm.
(run-layout-page): Mention Alt+Shift.
* gnu/installer/keymap.scm (kmscon-update-keymap): Pass on XKB options.
* gnu/installer/record.scm (&lt;installer&gt;): Adjust code comments.
* gnu/installer.scm (apply-keymap): Pass on XKB options.
(installer-steps): Adjust code comments.
* gnu/packages/patches/kmscon-runtime-keymap-switch.patch: Apply XKB options.
</span></span></td><td>Florian Pelz</td></tr>