/**
* Print a single package which:
* (a) is the target of one or more relevant predependencies.
* (b) has itself no unsatisfied pre-dependencies.
*
* If such a package is present output is the Packages file entry,
* which can be massaged as appropriate.
*
* Exit status:
* 0 = a package printed, OK
* 1 = no suitable package available
* 2 = error
*/
int
predeppackage(const char *const *argv)
{
static struct varbuf vb;
struct pkgiterator *it;
struct pkginfo *pkg = NULL, *startpkg, *trypkg;
struct dependency *dep;
struct deppossi *possi, *provider;
if (*argv)
badusage(_("--%s takes no arguments"), cipaction->olong);
modstatdb_open(msdbrw_readonly | msdbrw_available_readonly);
/* We use clientdata->istobe to detect loops. */
clear_istobes();
dep = NULL;
it = pkg_db_iter_new();
while (!dep && (pkg = pkg_db_iter_next_pkg(it))) {
/* Ignore packages user doesn't want. */
if (pkg->want != want_install)
continue;
/* Ignore packages not available. */
if (!pkg->files)
continue;
pkg->clientdata->istobe= itb_preinstall;
for (dep= pkg->available.depends; dep; dep= dep->next) {
if (dep->type != dep_predepends) continue;
if (depisok(dep, &vb, NULL, NULL, true))
continue;
/* This will leave dep non-NULL, and so exit the loop. */
break;
}
pkg->clientdata->istobe= itb_normal;
/* If dep is NULL we go and get the next package. */
}
pkg_db_iter_free(it);
if (!dep)
return 1; /* Not found. */
assert(pkg);
startpkg= pkg;
pkg->clientdata->istobe= itb_preinstall;
/* OK, we have found an unsatisfied predependency.
* Now go and find the first thing we need to install, as a first step
* towards satisfying it. */
do {
/* We search for a package which would satisfy dep, and put it in pkg. */
for (possi = dep->list, pkg = NULL;
!pkg && possi;
possi=possi->next) {
struct deppossi_pkg_iterator *possi_iter;
possi_iter = deppossi_pkg_iter_new(possi, wpb_available);
while (!pkg && (trypkg = deppossi_pkg_iter_next(possi_iter))) {
if (trypkg->files && trypkg->clientdata->istobe == itb_normal &&
versionsatisfied(&trypkg->available, possi)) {
pkg = trypkg;
break;
}
if (possi->verrel != dpkg_relation_none)
continue;
for (provider = possi->ed->depended.available;
!pkg && provider;
provider = provider->next) {
if (provider->up->type != dep_provides)
continue;
trypkg = provider->up->up;
if (!trypkg->files)
continue;
if (trypkg->clientdata->istobe == itb_normal) {
pkg = trypkg;
break;
}
}
}
deppossi_pkg_iter_free(possi_iter);
}
if (!pkg) {
varbuf_reset(&vb);
describedepcon(&vb,dep);
varbuf_end_str(&vb);
notice(_("cannot see how to satisfy pre-dependency:\n %s"), vb.buf);
ohshit(_("cannot satisfy pre-dependencies for %.250s (wanted due to %.250s)"),
pkgbin_name(dep->up, &dep->up->available, pnaw_nonambig),
pkgbin_name(startpkg, &startpkg->available, pnaw_nonambig));
}
pkg->clientdata->istobe= itb_preinstall;
for (dep= pkg->available.depends; dep; dep= dep->next) {
if (dep->type != dep_predepends) continue;
if (depisok(dep, &vb, NULL, NULL, true))
continue;
/* This will leave dep non-NULL, and so exit the loop. */
break;
}
} while (dep);
/* OK, we've found it - pkg has no unsatisfied pre-dependencies! */
writerecord(stdout, _("<standard output>"), pkg, &pkg->available);
m_output(stdout, _("<standard output>"));
return 0;
}
/*
* *whynot must already have been initialized; it need not be
* empty though - it will be reset before use.
*
* If depisok returns false for ‘not OK’ it will contain a description,
* newline-terminated BUT NOT NUL-TERMINATED, of the reason.
*
* If depisok returns true it will contain garbage.
* allowunconfigd should be non-zero during the ‘Pre-Depends’ checking
* before a package is unpacked, when it is sufficient for the package
* to be unpacked provided that both the unpacked and previously-configured
* versions are acceptable.
*
* On false return (‘not OK’), *canfixbyremove refers to a package which
* if removed (dep_conflicts) or deconfigured (dep_breaks) will fix
* the problem. Caller may pass NULL for canfixbyremove and need not
* initialize *canfixbyremove.
*
* On false return (‘not OK’), *canfixbytrigaw refers to a package which
* can fix the problem if all the packages listed in Triggers-Awaited have
* their triggers processed. Caller may pass NULL for canfixbytrigaw and
* need not initialize *canfixbytrigaw.
*/
bool
depisok(struct dependency *dep, struct varbuf *whynot,
struct pkginfo **canfixbyremove, struct pkginfo **canfixbytrigaw,
bool allowunconfigd)
{
struct deppossi *possi;
struct deppossi *provider;
struct pkginfo *pkg_pos;
int nconflicts;
/* Use this buffer so that when internationalisation comes along we
* don't have to rewrite the code completely, only redo the sprintf strings
* (assuming we have the fancy argument-number-specifiers).
* Allow 250x3 for package names, versions, &c, + 250 for ourselves. */
char linebuf[1024];
assert(dep->type == dep_depends || dep->type == dep_predepends ||
dep->type == dep_breaks || dep->type == dep_conflicts ||
dep->type == dep_recommends || dep->type == dep_suggests ||
dep->type == dep_enhances);
if (canfixbyremove)
*canfixbyremove = NULL;
if (canfixbytrigaw)
*canfixbytrigaw = NULL;
/* The dependency is always OK if we're trying to remove the depend*ing*
* package. */
switch (dep->up->clientdata->istobe) {
case itb_remove: case itb_deconfigure:
return true;
case itb_normal:
/* Only installed packages can be make dependency problems. */
switch (dep->up->status) {
case stat_installed:
case stat_triggerspending:
case stat_triggersawaited:
break;
case stat_notinstalled: case stat_configfiles: case stat_halfinstalled:
case stat_halfconfigured: case stat_unpacked:
return true;
default:
internerr("unknown status depending '%d'", dep->up->status);
}
break;
case itb_installnew: case itb_preinstall:
break;
default:
internerr("unknown istobe depending '%d'", dep->up->clientdata->istobe);
}
/* Describe the dependency, in case we have to moan about it. */
varbuf_reset(whynot);
varbuf_add_char(whynot, ' ');
describedepcon(whynot, dep);
varbuf_add_char(whynot, '\n');
/* TODO: Check dep_enhances as well. */
if (dep->type == dep_depends || dep->type == dep_predepends ||
dep->type == dep_recommends || dep->type == dep_suggests ) {
/* Go through the alternatives. As soon as we find one that
* we like, we return ‘true’ straight away. Otherwise, when we get to
* the end we'll have accumulated all the reasons in whynot and
* can return ‘false’. */
for (possi= dep->list; possi; possi= possi->next) {
struct deppossi_pkg_iterator *possi_iter;
possi_iter = deppossi_pkg_iter_new(possi, wpb_by_istobe);
while ((pkg_pos = deppossi_pkg_iter_next(possi_iter))) {
switch (pkg_pos->clientdata->istobe) {
case itb_remove:
sprintf(linebuf, _(" %.250s is to be removed.\n"),
pkg_name(pkg_pos, pnaw_nonambig));
break;
case itb_deconfigure:
sprintf(linebuf, _(" %.250s is to be deconfigured.\n"),
pkg_name(pkg_pos, pnaw_nonambig));
break;
case itb_installnew:
if (versionsatisfied(&pkg_pos->available, possi)) {
deppossi_pkg_iter_free(possi_iter);
return true;
}
sprintf(linebuf, _(" %.250s is to be installed, but is version "
"%.250s.\n"),
pkgbin_name(pkg_pos, &pkg_pos->available, pnaw_nonambig),
versiondescribe(&pkg_pos->available.version, vdew_nonambig));
break;
case itb_normal:
case itb_preinstall:
switch (pkg_pos->status) {
case stat_installed:
case stat_triggerspending:
if (versionsatisfied(&pkg_pos->installed, possi)) {
deppossi_pkg_iter_free(possi_iter);
return true;
}
sprintf(linebuf, _(" %.250s is installed, but is version "
"%.250s.\n"),
pkg_name(pkg_pos, pnaw_nonambig),
versiondescribe(&pkg_pos->installed.version, vdew_nonambig));
break;
case stat_notinstalled:
/* Don't say anything about this yet - it might be a virtual package.
* Later on, if nothing has put anything in linebuf, we know that it
* isn't and issue a diagnostic then. */
*linebuf = '\0';
break;
case stat_triggersawaited:
if (canfixbytrigaw && versionsatisfied(&pkg_pos->installed, possi))
*canfixbytrigaw = pkg_pos;
/* Fall through to have a chance to return OK due to
* allowunconfigd and to fill the explanation */
case stat_unpacked:
case stat_halfconfigured:
if (allowunconfigd) {
if (!dpkg_version_is_informative(&pkg_pos->configversion)) {
sprintf(linebuf, _(" %.250s is unpacked, but has never been "
"configured.\n"),
pkg_name(pkg_pos, pnaw_nonambig));
break;
} else if (!versionsatisfied(&pkg_pos->installed, possi)) {
sprintf(linebuf, _(" %.250s is unpacked, but is version "
"%.250s.\n"),
pkg_name(pkg_pos, pnaw_nonambig),
versiondescribe(&pkg_pos->installed.version,
vdew_nonambig));
break;
} else if (!dpkg_version_relate(&pkg_pos->configversion,
possi->verrel,
&possi->version)) {
sprintf(linebuf, _(" %.250s latest configured version is "
"%.250s.\n"),
pkg_name(pkg_pos, pnaw_nonambig),
versiondescribe(&pkg_pos->configversion, vdew_nonambig));
break;
} else {
deppossi_pkg_iter_free(possi_iter);
return true;
}
}
/* Fall through. */
default:
sprintf(linebuf, _(" %.250s is %s.\n"),
pkg_name(pkg_pos, pnaw_nonambig),
gettext(statusstrings[pkg_pos->status]));
break;
}
break;
default:
internerr("unknown istobe depended '%d'", pkg_pos->clientdata->istobe);
}
varbuf_add_str(whynot, linebuf);
}
deppossi_pkg_iter_free(possi_iter);
/* If there was no version specified we try looking for Providers. */
if (possi->verrel == dpkg_relation_none) {
/* See if the package we're about to install Provides it. */
for (provider = possi->ed->depended.available;
provider;
provider = provider->rev_next) {
if (provider->up->type != dep_provides) continue;
if (provider->up->up->clientdata->istobe == itb_installnew)
return true;
}
/* Now look at the packages already on the system. */
for (provider = possi->ed->depended.installed;
provider;
provider = provider->rev_next) {
if (provider->up->type != dep_provides) continue;
switch (provider->up->up->clientdata->istobe) {
case itb_installnew:
/* Don't pay any attention to the Provides field of the
* currently-installed version of the package we're trying
* to install. We dealt with that by using the available
* information above. */
continue;
case itb_remove:
sprintf(linebuf, _(" %.250s provides %.250s but is to be removed.\n"),
pkg_name(provider->up->up, pnaw_nonambig),
possi->ed->name);
break;
case itb_deconfigure:
sprintf(linebuf, _(" %.250s provides %.250s but is to be deconfigured.\n"),
pkg_name(provider->up->up, pnaw_nonambig),
possi->ed->name);
break;
case itb_normal: case itb_preinstall:
if (provider->up->up->status == stat_installed ||
provider->up->up->status == stat_triggerspending)
return true;
if (provider->up->up->status == stat_triggersawaited)
*canfixbytrigaw = provider->up->up;
sprintf(linebuf, _(" %.250s provides %.250s but is %s.\n"),
pkg_name(provider->up->up, pnaw_nonambig),
possi->ed->name,
gettext(statusstrings[provider->up->up->status]));
break;
default:
internerr("unknown istobe provider '%d'",
provider->up->up->clientdata->istobe);
}
varbuf_add_str(whynot, linebuf);
}
if (!*linebuf) {
/* If the package wasn't installed at all, and we haven't said
* yet why this isn't satisfied, we should say so now. */
sprintf(linebuf, _(" %.250s is not installed.\n"), possi->ed->name);
varbuf_add_str(whynot, linebuf);
}
}
}
return false;
} else {
/* It's conflicts or breaks. There's only one main alternative,
* but we also have to consider Providers. We return ‘false’ as soon
* as we find something that matches the conflict, and only describe
* it then. If we get to the end without finding anything we return
* ‘true’. */
possi= dep->list;
nconflicts= 0;
if (possi->ed != possi->up->up->set) {
struct deppossi_pkg_iterator *possi_iter;
/* If the package conflicts with or breaks itself it must mean
* other packages which provide the same virtual name. We
* therefore don't look at the real package and go on to the
* virtual ones. */
possi_iter = deppossi_pkg_iter_new(possi, wpb_by_istobe);
while ((pkg_pos = deppossi_pkg_iter_next(possi_iter))) {
switch (pkg_pos->clientdata->istobe) {
case itb_remove:
break;
case itb_installnew:
if (!versionsatisfied(&pkg_pos->available, possi))
break;
sprintf(linebuf, _(" %.250s (version %.250s) is to be installed.\n"),
pkgbin_name(pkg_pos, &pkg_pos->available, pnaw_nonambig),
versiondescribe(&pkg_pos->available.version, vdew_nonambig));
varbuf_add_str(whynot, linebuf);
if (!canfixbyremove) {
deppossi_pkg_iter_free(possi_iter);
return false;
}
nconflicts++;
*canfixbyremove = pkg_pos;
break;
case itb_deconfigure:
if (dep->type == dep_breaks)
break; /* Already deconfiguring this. */
/* Fall through. */
case itb_normal:
case itb_preinstall:
switch (pkg_pos->status) {
case stat_notinstalled:
case stat_configfiles:
break;
case stat_halfinstalled:
case stat_unpacked:
case stat_halfconfigured:
if (dep->type == dep_breaks)
break; /* No problem. */
case stat_installed:
case stat_triggerspending:
case stat_triggersawaited:
if (!versionsatisfied(&pkg_pos->installed, possi))
break;
sprintf(linebuf, _(" %.250s (version %.250s) is present and %s.\n"),
pkg_name(pkg_pos, pnaw_nonambig),
versiondescribe(&pkg_pos->installed.version, vdew_nonambig),
gettext(statusstrings[pkg_pos->status]));
varbuf_add_str(whynot, linebuf);
if (!canfixbyremove) {
deppossi_pkg_iter_free(possi_iter);
return false;
}
nconflicts++;
*canfixbyremove = pkg_pos;
}
break;
default:
internerr("unknown istobe conflict '%d'", pkg_pos->clientdata->istobe);
}
}
deppossi_pkg_iter_free(possi_iter);
}
/* If there was no version specified we try looking for Providers. */
if (possi->verrel == dpkg_relation_none) {
/* See if the package we're about to install Provides it. */
for (provider = possi->ed->depended.available;
provider;
provider = provider->rev_next) {
if (provider->up->type != dep_provides) continue;
if (provider->up->up->clientdata->istobe != itb_installnew) continue;
if (provider->up->up->set == dep->up->set)
continue; /* Conflicts and provides the same. */
sprintf(linebuf, _(" %.250s provides %.250s and is to be installed.\n"),
pkgbin_name(provider->up->up, &provider->up->up->available,
pnaw_nonambig), possi->ed->name);
varbuf_add_str(whynot, linebuf);
/* We can't remove the one we're about to install: */
if (canfixbyremove)
*canfixbyremove = NULL;
return false;
}
/* Now look at the packages already on the system. */
for (provider = possi->ed->depended.installed;
provider;
provider = provider->rev_next) {
if (provider->up->type != dep_provides) continue;
if (provider->up->up->set == dep->up->set)
continue; /* Conflicts and provides the same. */
switch (provider->up->up->clientdata->istobe) {
case itb_installnew:
/* Don't pay any attention to the Provides field of the
* currently-installed version of the package we're trying
* to install. We dealt with that package by using the
* available information above. */
continue;
case itb_remove:
continue;
case itb_deconfigure:
if (dep->type == dep_breaks)
continue; /* Already deconfiguring. */
case itb_normal: case itb_preinstall:
switch (provider->up->up->status) {
case stat_notinstalled: case stat_configfiles:
continue;
case stat_halfinstalled: case stat_unpacked:
case stat_halfconfigured:
if (dep->type == dep_breaks)
break; /* No problem. */
case stat_installed:
case stat_triggerspending:
case stat_triggersawaited:
sprintf(linebuf,
_(" %.250s provides %.250s and is present and %s.\n"),
pkg_name(provider->up->up, pnaw_nonambig), possi->ed->name,
gettext(statusstrings[provider->up->up->status]));
varbuf_add_str(whynot, linebuf);
if (!canfixbyremove)
return false;
nconflicts++;
*canfixbyremove= provider->up->up;
break;
}
break;
default:
internerr("unknown istobe conflict provider '%d'",
provider->up->up->clientdata->istobe);
}
}
}
if (!nconflicts)
return true;
if (nconflicts > 1)
*canfixbyremove = NULL;
return false;
} /* if (dependency) {...} else {...} */
}
/*
* Checks [Pre]-Depends only.
*/
enum dep_check
dependencies_ok(struct pkginfo *pkg, struct pkginfo *removing,
struct varbuf *aemsgs)
{
/* Valid values: 2 = ok, 1 = defer, 0 = halt. */
enum dep_check ok;
/* Valid values: 0 = none, 1 = defer, 2 = withwarning, 3 = ok. */
enum found_status found, thisf;
int interestingwarnings;
bool matched, anycannotfixbytrig;
struct varbuf oemsgs = VARBUF_INIT;
struct dependency *dep;
struct deppossi *possi, *provider;
struct pkginfo *possfixbytrig, *canfixbytrig;
interestingwarnings= 0;
ok = dep_check_ok;
debug(dbg_depcon,"checking dependencies of %s (- %s)",
pkg_name(pkg, pnaw_always),
removing ? pkg_name(removing, pnaw_always) : "<none>");
anycannotfixbytrig = false;
canfixbytrig = NULL;
for (dep= pkg->installed.depends; dep; dep= dep->next) {
if (dep->type != dep_depends && dep->type != dep_predepends) continue;
debug(dbg_depcondetail," checking group ...");
matched = false;
varbuf_reset(&oemsgs);
found = found_none;
possfixbytrig = NULL;
for (possi = dep->list; found != found_ok && possi; possi = possi->next) {
struct deppossi_pkg_iterator *possi_iter;
struct pkginfo *pkg_pos;
debug(dbg_depcondetail," checking possibility -> %s",possi->ed->name);
if (possi->cyclebreak) {
debug(dbg_depcondetail," break cycle so ok and found");
found = found_ok;
break;
}
thisf = found_none;
possi_iter = deppossi_pkg_iter_new(possi, wpb_installed);
while ((pkg_pos = deppossi_pkg_iter_next(possi_iter))) {
thisf = deppossi_ok_found(pkg_pos, pkg, removing, NULL,
&possfixbytrig, &matched, possi,
&interestingwarnings, &oemsgs);
if (thisf > found)
found = thisf;
if (found == found_ok)
break;
}
deppossi_pkg_iter_free(possi_iter);
if (found != found_ok && possi->verrel == dpkg_relation_none) {
for (provider = possi->ed->depended.installed;
found != found_ok && provider;
provider = provider->rev_next) {
if (provider->up->type != dep_provides)
continue;
debug(dbg_depcondetail, " checking provider %s",
pkg_name(provider->up->up, pnaw_always));
if (!deparchsatisfied(&provider->up->up->installed, provider->arch,
possi)) {
debug(dbg_depcondetail, " provider does not satisfy arch");
continue;
}
thisf = deppossi_ok_found(provider->up->up, pkg, removing,
possi->ed,
&possfixbytrig, &matched, NULL,
&interestingwarnings, &oemsgs);
if (thisf > found)
found = thisf;
}
}
debug(dbg_depcondetail," found %d",found);
if (thisf > found) found= thisf;
}
if (fc_depends) {
thisf = (dependtry >= 4) ? found_forced : found_defer;
if (thisf > found) {
found = thisf;
debug(dbg_depcondetail, " rescued by force-depends, found %d", found);
}
}
debug(dbg_depcondetail, " found %d matched %d possfixbytrig %s",
found, matched,
possfixbytrig ? pkg_name(possfixbytrig, pnaw_always) : "-");
if (removing && !matched) continue;
switch (found) {
case found_none:
anycannotfixbytrig = true;
ok = dep_check_halt;
case found_forced:
varbuf_add_str(aemsgs, " ");
varbuf_add_pkgbin_name(aemsgs, pkg, &pkg->installed, pnaw_nonambig);
varbuf_add_str(aemsgs, _(" depends on "));
varbufdependency(aemsgs, dep);
if (interestingwarnings) {
/* Don't print the line about the package to be removed if
* that's the only line. */
varbuf_end_str(&oemsgs);
varbuf_add_str(aemsgs, _("; however:\n"));
varbuf_add_str(aemsgs, oemsgs.buf);
} else {
varbuf_add_str(aemsgs, ".\n");
}
break;
case found_defer:
if (possfixbytrig)
canfixbytrig = possfixbytrig;
else
anycannotfixbytrig = true;
if (ok > dep_check_defer)
ok = dep_check_defer;
break;
case found_ok:
break;
default:
internerr("unknown value for found '%d'", found);
}
}
if (ok == dep_check_halt &&
(pkg->clientdata && pkg->clientdata->istobe == itb_remove))
ok = dep_check_defer;
if (!anycannotfixbytrig && canfixbytrig)
progress_bytrigproc = canfixbytrig;
varbuf_destroy(&oemsgs);
debug(dbg_depcon,"ok %d msgs >>%.*s<<", ok, (int)aemsgs->used, aemsgs->buf);
return ok;
}
/**
* Cycle breaking works recursively down the package dependency tree.
*
* ‘sofar’ is the list of packages we've descended down already - if we
* encounter any of its packages again in a dependency we have found a cycle.
*/
static bool
findbreakcyclerecursive(struct pkginfo *pkg, struct cyclesofarlink *sofar)
{
struct cyclesofarlink thislink, *sol;
struct dependency *dep;
struct deppossi *possi, *providelink;
struct pkginfo *provider, *pkg_pos;
if (pkg->clientdata->color == black)
return false;
pkg->clientdata->color = gray;
if (debug_has_flag(dbg_depcondetail)) {
struct varbuf str_pkgs = VARBUF_INIT;
for (sol = sofar; sol; sol = sol->prev) {
varbuf_add_str(&str_pkgs, " <- ");
varbuf_add_pkgbin_name(&str_pkgs, sol->pkg, &sol->pkg->installed, pnaw_nonambig);
}
varbuf_end_str(&str_pkgs);
debug(dbg_depcondetail, "findbreakcyclerecursive %s %s",
pkg_name(pkg, pnaw_always), str_pkgs.buf);
varbuf_destroy(&str_pkgs);
}
thislink.pkg= pkg;
thislink.prev = sofar;
thislink.possi = NULL;
for (dep= pkg->installed.depends; dep; dep= dep->next) {
if (dep->type != dep_depends && dep->type != dep_predepends) continue;
for (possi= dep->list; possi; possi= possi->next) {
struct deppossi_pkg_iterator *possi_iter;
/* Don't find the same cycles again. */
if (possi->cyclebreak) continue;
thislink.possi= possi;
possi_iter = deppossi_pkg_iter_new(possi, wpb_installed);
while ((pkg_pos = deppossi_pkg_iter_next(possi_iter)))
if (foundcyclebroken(&thislink, sofar, pkg_pos, possi)) {
deppossi_pkg_iter_free(possi_iter);
return true;
}
deppossi_pkg_iter_free(possi_iter);
/* Right, now we try all the providers ... */
for (providelink = possi->ed->depended.installed;
providelink;
providelink = providelink->rev_next) {
if (providelink->up->type != dep_provides) continue;
provider= providelink->up->up;
if (provider->clientdata->istobe == itb_normal) continue;
/* We don't break things at ‘provides’ links, so ‘possi’ is
* still the one we use. */
if (foundcyclebroken(&thislink, sofar, provider, possi))
return true;
}
}
}
/* Nope, we didn't find a cycle to break. */
pkg->clientdata->color = black;
return false;
}