Adding upstream version 1.22.4.upstream/1.22.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 825 insertions, 0 deletions

diff --git a/src/main/configure.c b/src/main/configure.c
new file mode 100644
index 0000000..c2d58c7
--- /dev/null
+++ b/src/main/configure.c
@@ -0,0 +1,825 @@
+/*
+ * dpkg - main program for package management
+ * configure.c - configure packages
+ *
+ * Copyright © 1995 Ian Jackson <ijackson@chiark.greenend.org.uk>
+ * Copyright © 1999, 2002 Wichert Akkerman <wichert@deephackmode.org>
+ * Copyright © 2007-2015 Guillem Jover <guillem@debian.org>
+ * Copyright © 2011 Linaro Limited
+ * Copyright © 2011 Raphaël Hertzog <hertzog@debian.org>
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <compat.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+
+#include <errno.h>
+#include <ctype.h>
+#include <string.h>
+#include <time.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <termios.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include <dpkg/macros.h>
+#include <dpkg/i18n.h>
+#include <dpkg/dpkg.h>
+#include <dpkg/dpkg-db.h>
+#include <dpkg/pkg.h>
+#include <dpkg/string.h>
+#include <dpkg/buffer.h>
+#include <dpkg/file.h>
+#include <dpkg/path.h>
+#include <dpkg/subproc.h>
+#include <dpkg/command.h>
+#include <dpkg/pager.h>
+#include <dpkg/triglib.h>
+#include <dpkg/db-fsys.h>
+
+#include "main.h"
+
+enum DPKG_ATTR_ENUM_FLAGS conffopt {
+	CFOF_PROMPT		= DPKG_BIT(0),
+	CFOF_KEEP		= DPKG_BIT(1),
+	CFOF_INSTALL		= DPKG_BIT(2),
+	CFOF_BACKUP		= DPKG_BIT(3),
+	CFOF_NEW_CONFF		= DPKG_BIT(4),
+	CFOF_IS_NEW		= DPKG_BIT(5),
+	CFOF_IS_OLD		= DPKG_BIT(6),
+	CFOF_USER_DEL		= DPKG_BIT(7),
+
+	CFO_KEEP		= CFOF_KEEP,
+	CFO_IDENTICAL		= CFOF_KEEP,
+	CFO_INSTALL		= CFOF_INSTALL,
+	CFO_NEW_CONFF		= CFOF_NEW_CONFF | CFOF_INSTALL,
+	CFO_PROMPT		= CFOF_PROMPT,
+	CFO_PROMPT_KEEP		= CFOF_PROMPT | CFOF_KEEP,
+	CFO_PROMPT_INSTALL	= CFOF_PROMPT | CFOF_INSTALL,
+};
+
+static int conffoptcells[2][2] = {
+	/* Distro !edited. */	/* Distro edited. */
+	{ CFO_KEEP,		CFO_INSTALL },		/* User !edited. */
+	{ CFO_KEEP,		CFO_PROMPT_KEEP },	/* User edited. */
+};
+
+static int
+show_prompt(const char *cfgfile, const char *realold, const char *realnew,
+            int useredited, int distedited, enum conffopt what)
+{
+	const char *s;
+	int c, cc;
+
+	/* Flush the terminal's input in case the user involuntarily
+	 * typed some characters. */
+	tcflush(STDIN_FILENO, TCIFLUSH);
+
+	fputs("\n", stderr);
+	if (strcmp(cfgfile, realold) == 0)
+		fprintf(stderr, _("Configuration file '%s'\n"), cfgfile);
+	else
+		fprintf(stderr, _("Configuration file '%s' (actually '%s')\n"),
+		        cfgfile, realold);
+
+	if (what & CFOF_IS_NEW) {
+		fprintf(stderr,
+		        _(" ==> File on system created by you or by a script.\n"
+		          " ==> File also in package provided by package maintainer.\n"));
+	} else {
+		fprintf(stderr, !useredited ?
+		        _("     Not modified since installation.\n") :
+		        !(what & CFOF_USER_DEL) ?
+		        _(" ==> Modified (by you or by a script) since installation.\n") :
+		        _(" ==> Deleted (by you or by a script) since installation.\n"));
+
+		fprintf(stderr, distedited ?
+		        _(" ==> Package distributor has shipped an updated version.\n") :
+		        _("     Version in package is the same as at last installation.\n"));
+	}
+
+	/* No --force-confdef but a forcible situation. */
+	/* TODO: check if this condition can not be simplified to
+	 *       just !in_force(FORCE_CONFF_DEF) */
+	if (!(in_force(FORCE_CONFF_DEF) && (what & (CFOF_INSTALL | CFOF_KEEP)))) {
+		if (in_force(FORCE_CONFF_NEW)) {
+			fprintf(stderr,
+			        _(" ==> Using new file as you requested.\n"));
+			return 'y';
+		} else if (in_force(FORCE_CONFF_OLD)) {
+			fprintf(stderr,
+			        _(" ==> Using current old file as you requested.\n"));
+			return 'n';
+		}
+	}
+
+	/* Force the default action (if there is one. */
+	if (in_force(FORCE_CONFF_DEF)) {
+		if (what & CFOF_KEEP) {
+			fprintf(stderr,
+			        _(" ==> Keeping old config file as default.\n"));
+			return 'n';
+		} else if (what & CFOF_INSTALL) {
+			fprintf(stderr,
+			        _(" ==> Using new config file as default.\n"));
+			return 'y';
+		}
+	}
+
+	fprintf(stderr,
+	        _("   What would you like to do about it ?  Your options are:\n"
+	          "    Y or I  : install the package maintainer's version\n"
+	          "    N or O  : keep your currently-installed version\n"
+	          "      D     : show the differences between the versions\n"
+	          "      Z     : start a shell to examine the situation\n"));
+
+	if (what & CFOF_KEEP)
+		fprintf(stderr,
+		        _(" The default action is to keep your current version.\n"));
+	else if (what & CFOF_INSTALL)
+		fprintf(stderr,
+		        _(" The default action is to install the new version.\n"));
+
+	s = path_basename(cfgfile);
+	fprintf(stderr, "*** %s (Y/I/N/O/D/Z) %s ? ", s,
+	        (what & CFOF_KEEP) ? _("[default=N]") :
+	        (what & CFOF_INSTALL) ? _("[default=Y]") :
+	        _("[no default]"));
+
+	if (ferror(stderr))
+		ohshite(_("error writing to stderr, discovered before conffile prompt"));
+
+	cc = 0;
+	while ((c = getchar()) != EOF && c != '\n')
+		if (!isspace(c) && !cc)
+			cc = tolower(c);
+
+	if (c == EOF) {
+		if (ferror(stdin))
+			ohshite(_("read error on stdin at conffile prompt"));
+		ohshit(_("end of file on stdin at conffile prompt"));
+	}
+
+	if (!cc) {
+		if (what & CFOF_KEEP)
+			return 'n';
+		else if (what & CFOF_INSTALL)
+			return 'y';
+	}
+
+	return cc;
+}
+
+/**
+ * Show a diff between two files.
+ *
+ * @param old The path to the old file.
+ * @param new The path to the new file.
+ */
+static void
+show_diff(const char *old, const char *new)
+{
+	struct pager *pager;
+	pid_t pid;
+
+	pager = pager_spawn(_("conffile difference visualizer"));
+
+	pid = subproc_fork();
+	if (!pid) {
+		/* Child process. */
+		struct command cmd;
+
+		command_init(&cmd, DIFF, _("conffile difference visualizer"));
+		command_add_arg(&cmd, DIFF);
+		command_add_arg(&cmd, "-Nu");
+		command_add_arg(&cmd, old);
+		command_add_arg(&cmd, new);
+		command_exec(&cmd);
+	}
+
+	/* Parent process. */
+	subproc_reap(pid, _("conffile difference visualizer"), SUBPROC_NOCHECK);
+	pager_reap(pager);
+}
+
+/**
+ * Spawn a new shell.
+ *
+ * Create a subprocess and execute a shell to allow the user to manually
+ * solve the conffile conflict.
+ *
+ * @param confold The path to the old conffile.
+ * @param confnew The path to the new conffile.
+ */
+static void
+spawn_shell(const char *confold, const char *confnew)
+{
+	pid_t pid;
+
+	fputs(_("Useful environment variables:\n"), stderr);
+	fputs(" - DPKG_SHELL_REASON\n", stderr);
+	fputs(" - DPKG_CONFFILE_OLD\n", stderr);
+	fputs(" - DPKG_CONFFILE_NEW\n", stderr);
+	fputs(_("Type 'exit' when you're done.\n"), stderr);
+
+	pid = subproc_fork();
+	if (!pid) {
+		/* Set useful variables for the user. */
+		setenv("DPKG_SHELL_REASON", "conffile-prompt", 1);
+		setenv("DPKG_CONFFILE_OLD", confold, 1);
+		setenv("DPKG_CONFFILE_NEW", confnew, 1);
+
+		command_shell(NULL, _("conffile shell"));
+	}
+
+	/* Parent process. */
+	subproc_reap(pid, _("conffile shell"), SUBPROC_NOCHECK);
+}
+
+/**
+ * Prompt the user for how to resolve a conffile conflict.
+ *
+ * When encountering a conffile conflict during configuration, the user will
+ * normally be presented with a textual menu of possible actions. This
+ * behavior is modified via various --force flags and perhaps on whether
+ * or not a terminal is available to do the prompting.
+ *
+ * @param pkg The package owning the conffile.
+ * @param cfgfile The path to the old conffile.
+ * @param realold The path to the old conffile, dereferenced in case of a
+ *        symlink, otherwise equal to cfgfile.
+ * @param realnew The path to the new conffile, dereferenced in case of a
+ *        symlink).
+ * @param useredited A flag to indicate whether the file has been edited
+ *        locally. Set to nonzero to indicate that the file has been modified.
+ * @param distedited A flag to indicate whether the file has been updated
+ *        between package versions. Set to nonzero to indicate that the file
+ *        has been updated.
+ * @param what Hints on what action should be taken by default.
+ *
+ * @return The action which should be taken based on user input and/or the
+ *         default actions as configured by cmdline/configuration options.
+ */
+static enum conffopt
+promptconfaction(struct pkginfo *pkg, const char *cfgfile,
+                 const char *realold, const char *realnew,
+                 int useredited, int distedited, enum conffopt what)
+{
+	int cc;
+
+	if (!(what & CFOF_PROMPT))
+		return what;
+
+	statusfd_send("status: %s : %s : '%s' '%s' %i %i ",
+	              cfgfile, "conffile-prompt",
+	              realold, realnew, useredited, distedited);
+
+	do {
+		cc = show_prompt(cfgfile, realold, realnew,
+		                 useredited, distedited, what);
+
+		/* FIXME: Say something if silently not install. */
+		if (cc == 'd')
+			show_diff(realold, realnew);
+
+		if (cc == 'z')
+			spawn_shell(realold, realnew);
+	} while (!strchr("yino", cc));
+
+	log_message("conffile %s %s", cfgfile,
+	            (cc == 'i' || cc == 'y') ? "install" : "keep");
+
+	what &= CFOF_USER_DEL;
+
+	switch (cc) {
+	case 'i':
+	case 'y':
+		what |= CFOF_INSTALL | CFOF_BACKUP;
+		break;
+
+	case 'n':
+	case 'o':
+		what |= CFOF_KEEP | CFOF_BACKUP;
+		break;
+
+	default:
+		internerr("unknown response '%d'", cc);
+	}
+
+	return what;
+}
+
+/**
+ * Configure the ghost conffile instance.
+ *
+ * When the first instance of a package set is configured, the *.dpkg-new
+ * files gets installed into their destination, which makes configuration of
+ * conffiles from subsequent package instances be skipped along with updates
+ * to the Conffiles field hash.
+ *
+ * In case the conffile has already been processed, sync the hash from an
+ * already configured package instance conffile.
+ *
+ * @param pkg	The current package being configured.
+ * @param conff	The current conffile being configured.
+ */
+static void
+deferred_configure_ghost_conffile(struct pkginfo *pkg, struct conffile *conff)
+{
+	struct pkginfo *otherpkg;
+	struct conffile *otherconff;
+
+	for (otherpkg = &pkg->set->pkg; otherpkg; otherpkg = otherpkg->arch_next) {
+		if (otherpkg == pkg)
+			continue;
+		if (otherpkg->status <= PKG_STAT_HALFCONFIGURED)
+			continue;
+
+		for (otherconff = otherpkg->installed.conffiles; otherconff;
+		     otherconff = otherconff->next) {
+			if (otherconff->obsolete || otherconff->remove_on_upgrade)
+				continue;
+
+			/* Check if we need to propagate the new hash from
+			 * an already processed conffile in another package
+			 * instance. */
+			if (strcmp(otherconff->name, conff->name) == 0) {
+				conff->hash = otherconff->hash;
+				modstatdb_note(pkg);
+				return;
+			}
+		}
+	}
+}
+
+static void
+deferred_configure_conffile(struct pkginfo *pkg, struct conffile *conff)
+{
+	struct fsys_namenode *usenode;
+	char currenthash[MD5HASHLEN + 1], newdisthash[MD5HASHLEN + 1];
+	int useredited, distedited;
+	enum conffopt what;
+	struct stat stab;
+	struct varbuf cdr = VARBUF_INIT, cdr2 = VARBUF_INIT;
+	char *cdr2rest;
+	int rc;
+
+	usenode = namenodetouse(fsys_hash_find_node(conff->name, FHFF_NO_COPY),
+                                pkg, &pkg->installed);
+
+	rc = conffderef(pkg, &cdr, usenode->name);
+	if (rc == -1) {
+		conff->hash = EMPTYHASHFLAG;
+		return;
+	}
+	md5hash(pkg, currenthash, cdr.buf);
+
+	varbuf_set_varbuf(&cdr2, &cdr);
+	/* XXX: Make sure there's enough room for extensions. */
+	varbuf_grow(&cdr2, 50);
+	cdr2rest = cdr2.buf + strlen(cdr.buf);
+	/* From now on we can just strcpy(cdr2rest, extension); */
+
+	strcpy(cdr2rest, DPKGNEWEXT);
+	/* If the .dpkg-new file is no longer there, ignore this one. */
+	if (lstat(cdr2.buf, &stab)) {
+		if (errno == ENOENT) {
+			/* But, sync the conffile hash value from another
+			 * package set instance. */
+			deferred_configure_ghost_conffile(pkg, conff);
+			return;
+		}
+		ohshite(_("unable to stat new distributed conffile '%.250s'"),
+		        cdr2.buf);
+	}
+	md5hash(pkg, newdisthash, cdr2.buf);
+
+	/* Copy the permissions from the installed version to the new
+	 * distributed version. */
+	if (!stat(cdr.buf, &stab))
+		file_copy_perms(cdr.buf, cdr2.buf);
+	else if (errno != ENOENT)
+		ohshite(_("unable to stat current installed conffile '%.250s'"),
+		        cdr.buf);
+
+	/* Select what to do. */
+	if (strcmp(currenthash, newdisthash) == 0) {
+		/* They're both the same so there's no point asking silly
+		 * questions. */
+		useredited = -1;
+		distedited = -1;
+		what = CFO_IDENTICAL;
+	} else if (strcmp(currenthash, NONEXISTENTFLAG) == 0 && in_force(FORCE_CONFF_MISS)) {
+		fprintf(stderr,
+		        _("\n"
+		          "Configuration file '%s', does not exist on system.\n"
+		          "Installing new config file as you requested.\n"),
+		        usenode->name);
+		what = CFO_NEW_CONFF;
+		useredited = -1;
+		distedited = -1;
+	} else if (strcmp(conff->hash, NEWCONFFILEFLAG) == 0) {
+		if (strcmp(currenthash, NONEXISTENTFLAG) == 0) {
+			what = CFO_NEW_CONFF;
+			useredited = -1;
+			distedited = -1;
+		} else {
+			useredited = 1;
+			distedited = 1;
+			what = conffoptcells[useredited][distedited] |
+			       CFOF_IS_NEW;
+		}
+	} else {
+		useredited = strcmp(conff->hash, currenthash) != 0;
+		distedited = strcmp(conff->hash, newdisthash) != 0;
+
+		if (in_force(FORCE_CONFF_ASK) && useredited)
+			what = CFO_PROMPT_KEEP;
+		else
+			what = conffoptcells[useredited][distedited];
+
+		if (strcmp(currenthash, NONEXISTENTFLAG) == 0)
+			what |= CFOF_USER_DEL;
+	}
+
+	debug(dbg_conff,
+	      "deferred_configure '%s' (= '%s') useredited=%d distedited=%d what=%o",
+	      usenode->name, cdr.buf, useredited, distedited, what);
+
+	what = promptconfaction(pkg, usenode->name, cdr.buf, cdr2.buf,
+	                        useredited, distedited, what);
+
+	switch (what & ~(CFOF_IS_NEW | CFOF_USER_DEL)) {
+	case CFO_KEEP | CFOF_BACKUP:
+		strcpy(cdr2rest, DPKGOLDEXT);
+		if (unlink(cdr2.buf) && errno != ENOENT)
+			warning(_("%s: failed to remove old backup '%.250s': %s"),
+			        pkg_name(pkg, pnaw_nonambig), cdr2.buf,
+			        strerror(errno));
+
+		varbuf_add_str(&cdr, DPKGDISTEXT);
+		varbuf_end_str(&cdr);
+		strcpy(cdr2rest, DPKGNEWEXT);
+		trig_path_activate(usenode, pkg);
+		if (rename(cdr2.buf, cdr.buf))
+			warning(_("%s: failed to rename '%.250s' to '%.250s': %s"),
+			        pkg_name(pkg, pnaw_nonambig), cdr2.buf, cdr.buf,
+			        strerror(errno));
+		break;
+	case CFO_KEEP:
+		strcpy(cdr2rest, DPKGNEWEXT);
+		if (unlink(cdr2.buf))
+			warning(_("%s: failed to remove '%.250s': %s"),
+			        pkg_name(pkg, pnaw_nonambig), cdr2.buf,
+			        strerror(errno));
+		break;
+	case CFO_INSTALL | CFOF_BACKUP:
+		strcpy(cdr2rest, DPKGDISTEXT);
+		if (unlink(cdr2.buf) && errno != ENOENT)
+			warning(_("%s: failed to remove old distributed version '%.250s': %s"),
+			        pkg_name(pkg, pnaw_nonambig), cdr2.buf,
+			        strerror(errno));
+		strcpy(cdr2rest, DPKGOLDEXT);
+		if (unlink(cdr2.buf) && errno != ENOENT)
+			warning(_("%s: failed to remove '%.250s' (before overwrite): %s"),
+			        pkg_name(pkg, pnaw_nonambig), cdr2.buf,
+			        strerror(errno));
+		if (!(what & CFOF_USER_DEL))
+			if (link(cdr.buf, cdr2.buf))
+				warning(_("%s: failed to link '%.250s' to '%.250s': %s"),
+				        pkg_name(pkg, pnaw_nonambig), cdr.buf,
+				        cdr2.buf, strerror(errno));
+		/* Fall through. */
+	case CFO_INSTALL:
+		printf(_("Installing new version of config file %s ...\n"),
+		       usenode->name);
+		/* Fall through. */
+	case CFO_NEW_CONFF:
+		strcpy(cdr2rest, DPKGNEWEXT);
+		trig_path_activate(usenode, pkg);
+		if (rename(cdr2.buf, cdr.buf))
+			ohshite(_("unable to install '%.250s' as '%.250s'"),
+			        cdr2.buf, cdr.buf);
+		break;
+	default:
+		internerr("unknown conffopt '%d'", what);
+	}
+
+	conff->hash = nfstrsave(newdisthash);
+	modstatdb_note(pkg);
+
+	varbuf_destroy(&cdr);
+	varbuf_destroy(&cdr2);
+}
+
+/**
+ * Process the deferred configure package.
+ *
+ * @param pkg The package to act on.
+ */
+void
+deferred_configure(struct pkginfo *pkg)
+{
+	struct varbuf aemsgs = VARBUF_INIT;
+	struct conffile *conff;
+	struct pkginfo *otherpkg;
+	enum dep_check ok;
+
+	if (pkg->status == PKG_STAT_NOTINSTALLED)
+		ohshit(_("no package named '%s' is installed, cannot configure"),
+		       pkg_name(pkg, pnaw_nonambig));
+	if (pkg->status == PKG_STAT_INSTALLED)
+		ohshit(_("package %.250s is already installed and configured"),
+		       pkg_name(pkg, pnaw_nonambig));
+	if (pkg->status != PKG_STAT_UNPACKED &&
+	    pkg->status != PKG_STAT_HALFCONFIGURED)
+		ohshit(_("package %.250s is not ready for configuration\n"
+		         " cannot configure (current status '%.250s')"),
+		       pkg_name(pkg, pnaw_nonambig),
+		       pkg_status_name(pkg));
+
+	for (otherpkg = &pkg->set->pkg; otherpkg; otherpkg = otherpkg->arch_next) {
+		if (otherpkg == pkg)
+			continue;
+		if (otherpkg->status <= PKG_STAT_CONFIGFILES)
+			continue;
+
+		if (otherpkg->status < PKG_STAT_UNPACKED)
+			ohshit(_("package %s cannot be configured because "
+			         "%s is not ready (current status '%s')"),
+			       pkg_name(pkg, pnaw_always),
+			       pkg_name(otherpkg, pnaw_always),
+			       pkg_status_name(otherpkg));
+
+		if (dpkg_version_compare(&pkg->installed.version,
+		                         &otherpkg->installed.version))
+			ohshit(_("package %s %s cannot be configured because "
+			         "%s is at a different version (%s)"),
+			       pkg_name(pkg, pnaw_always),
+			       versiondescribe(&pkg->installed.version,
+			                       vdew_nonambig),
+			       pkg_name(otherpkg, pnaw_always),
+			       versiondescribe(&otherpkg->installed.version,
+			                       vdew_nonambig));
+	}
+
+	if (dependtry >= DEPEND_TRY_CYCLES)
+		if (findbreakcycle(pkg))
+			sincenothing = 0;
+
+	ok = dependencies_ok(pkg, NULL, &aemsgs);
+	if (ok == DEP_CHECK_DEFER) {
+		varbuf_destroy(&aemsgs);
+		ensure_package_clientdata(pkg);
+		pkg->clientdata->istobe = PKG_ISTOBE_INSTALLNEW;
+		enqueue_package(pkg);
+		return;
+	}
+
+	trigproc_reset_cycle();
+
+	/*
+	 * At this point removal from the queue is confirmed. This
+	 * represents irreversible progress wrt trigger cycles. Only
+	 * packages in PKG_STAT_UNPACKED are automatically added to the
+	 * configuration queue, and during configuration and trigger
+	 * processing new packages can't enter into unpacked.
+	 */
+
+	ok = breakses_ok(pkg, &aemsgs) ? ok : DEP_CHECK_HALT;
+	if (ok == DEP_CHECK_HALT) {
+		sincenothing = 0;
+		varbuf_end_str(&aemsgs);
+		notice(_("dependency problems prevent configuration of %s:\n%s"),
+		       pkg_name(pkg, pnaw_nonambig), aemsgs.buf);
+		varbuf_destroy(&aemsgs);
+		ohshit(_("dependency problems - leaving unconfigured"));
+	} else if (aemsgs.used) {
+		varbuf_end_str(&aemsgs);
+		notice(_("%s: dependency problems, but configuring anyway as you requested:\n%s"),
+		       pkg_name(pkg, pnaw_nonambig), aemsgs.buf);
+	}
+	varbuf_destroy(&aemsgs);
+	sincenothing = 0;
+
+	if (pkg->eflag & PKG_EFLAG_REINSTREQ)
+		forcibleerr(FORCE_REMOVE_REINSTREQ,
+		            _("package is in a very bad inconsistent state; you should\n"
+		              " reinstall it before attempting configuration"));
+
+	printf(_("Setting up %s (%s) ...\n"), pkg_name(pkg, pnaw_nonambig),
+	       versiondescribe(&pkg->installed.version, vdew_nonambig));
+	log_action("configure", pkg, &pkg->installed);
+
+	trig_activate_packageprocessing(pkg);
+
+	if (f_noact) {
+		pkg_set_status(pkg, PKG_STAT_INSTALLED);
+		ensure_package_clientdata(pkg);
+		pkg->clientdata->istobe = PKG_ISTOBE_NORMAL;
+		return;
+	}
+
+	if (pkg->status == PKG_STAT_UNPACKED) {
+		debug(dbg_general, "deferred_configure updating conffiles");
+		/* This will not do at all the right thing with overridden
+		 * conffiles or conffiles that are the ‘target’ of an override;
+		 * all the references here would be to the ‘contested’
+		 * filename, and in any case there'd only be one hash for both
+		 * ‘versions’ of the conffile.
+		 *
+		 * Overriding conffiles is a silly thing to do anyway :-). */
+
+		modstatdb_note(pkg);
+
+		/* On entry, the ‘new’ version of each conffile has been
+		 * unpacked as ‘*.dpkg-new’, and the ‘installed’ version is
+		 * as-yet untouched in ‘*’. The hash of the ‘old distributed’
+		 * version is in the conffiles data for the package. If
+		 * ‘*.dpkg-new’ no longer exists we assume that we've
+		 * already processed this one. */
+		for (conff = pkg->installed.conffiles; conff; conff = conff->next) {
+			if (conff->obsolete || conff->remove_on_upgrade)
+				continue;
+			deferred_configure_conffile(pkg, conff);
+		}
+
+		pkg_set_status(pkg, PKG_STAT_HALFCONFIGURED);
+	}
+
+	if (pkg->status != PKG_STAT_HALFCONFIGURED)
+		internerr("package %s in state %s, instead of half-configured",
+		          pkg_name(pkg, pnaw_always), pkg_status_name(pkg));
+
+	modstatdb_note(pkg);
+
+	maintscript_postinst(pkg, "configure",
+	                     dpkg_version_is_informative(&pkg->configversion) ?
+	                     versiondescribe(&pkg->configversion,
+	                                     vdew_nonambig) : "",
+	                     NULL);
+
+	pkg_reset_eflags(pkg);
+	pkg->trigpend_head = NULL;
+	post_postinst_tasks(pkg, PKG_STAT_INSTALLED);
+}
+
+/**
+ * Dereference a file by following all possibly used symlinks.
+ *
+ * @param[in] pkg The package to act on.
+ * @param[out] result The dereference conffile path.
+ * @param[in] in The conffile path to dereference.
+ *
+ * @return An error code for the operation.
+ * @retval 0 Everything went ok.
+ * @retval -1 Otherwise.
+ */
+int
+conffderef(struct pkginfo *pkg, struct varbuf *result, const char *in)
+{
+	static struct varbuf target = VARBUF_INIT;
+	struct stat stab;
+	ssize_t r;
+	int loopprotect;
+
+	varbuf_set_str(result, dpkg_fsys_get_dir());
+	varbuf_add_str(result, in);
+	varbuf_end_str(result);
+
+	loopprotect = 0;
+
+	for (;;) {
+		debug(dbg_conffdetail, "conffderef in='%s' current working='%s'",
+		      in, result->buf);
+		if (lstat(result->buf, &stab)) {
+			if (errno != ENOENT)
+				warning(_("%s: unable to stat config file '%s'\n"
+				          " (= '%s'): %s"),
+				        pkg_name(pkg, pnaw_nonambig), in,
+				        result->buf, strerror(errno));
+			debug(dbg_conffdetail, "conffderef nonexistent");
+			return 0;
+		} else if (S_ISREG(stab.st_mode)) {
+			debug(dbg_conff, "conffderef in='%s' result='%s'",
+			      in, result->buf);
+			return 0;
+		} else if (S_ISLNK(stab.st_mode)) {
+			debug(dbg_conffdetail, "conffderef symlink loopprotect=%d",
+			      loopprotect);
+			if (loopprotect++ >= 25) {
+				warning(_("%s: config file '%s' is a circular link\n"
+				          " (= '%s')"),
+				        pkg_name(pkg, pnaw_nonambig), in,
+				        result->buf);
+				return -1;
+			}
+
+			varbuf_reset(&target);
+			varbuf_grow(&target, stab.st_size + 1);
+			r = readlink(result->buf, target.buf, target.size);
+			if (r < 0) {
+				warning(_("%s: unable to readlink conffile '%s'\n"
+				          " (= '%s'): %s"),
+				        pkg_name(pkg, pnaw_nonambig), in,
+				        result->buf, strerror(errno));
+				return -1;
+			} else if (r != stab.st_size) {
+				warning(_("symbolic link '%.250s' size has "
+				          "changed from %jd to %zd"),
+				        result->buf, (intmax_t)stab.st_size, r);
+				/* If the returned size is smaller, let's
+				 * proceed, otherwise error out. */
+				if (r > stab.st_size)
+					return -1;
+			}
+			varbuf_trunc(&target, r);
+			varbuf_end_str(&target);
+
+			debug(dbg_conffdetail,
+			      "conffderef readlink gave %zd, '%s'",
+			      r, target.buf);
+
+			if (target.buf[0] == '/') {
+				varbuf_set_str(result, dpkg_fsys_get_dir());
+				debug(dbg_conffdetail,
+				      "conffderef readlink absolute");
+			} else {
+				for (r = result->used - 1; r > 0 && result->buf[r] != '/'; r--)
+					;
+				if (r < 0) {
+					warning(_("%s: conffile '%.250s' resolves to degenerate filename\n"
+					          " ('%s' is a symlink to '%s')"),
+					        pkg_name(pkg, pnaw_nonambig),
+					        in, result->buf, target.buf);
+					return -1;
+				}
+				if (result->buf[r] == '/')
+					r++;
+				varbuf_trunc(result, r);
+				debug(dbg_conffdetail,
+				      "conffderef readlink relative to '%.*s'",
+				      (int)result->used, result->buf);
+			}
+			varbuf_add_varbuf(result, &target);
+			varbuf_end_str(result);
+		} else {
+			warning(_("%s: conffile '%.250s' is not a plain file or symlink (= '%s')"),
+			        pkg_name(pkg, pnaw_nonambig), in, result->buf);
+			return -1;
+		}
+	}
+}
+
+/**
+ * Generate a file contents MD5 hash.
+ *
+ * The caller is responsible for providing a buffer for the hash result
+ * at least MD5HASHLEN + 1 characters long.
+ *
+ * @param[in] pkg The package to act on.
+ * @param[out] hashbuf The buffer to store the generated hash.
+ * @param[in] fn The filename.
+ */
+void
+md5hash(struct pkginfo *pkg, char *hashbuf, const char *fn)
+{
+	struct dpkg_error err;
+	static int fd;
+
+	fd = open(fn, O_RDONLY);
+
+	if (fd >= 0) {
+		push_cleanup(cu_closefd, ehflag_bombout, 1, &fd);
+		if (fd_md5(fd, hashbuf, -1, &err) < 0)
+			ohshit(_("cannot compute MD5 digest for file '%s': %s"),
+			       fn, err.str);
+		pop_cleanup(ehflag_normaltidy); /* fd = open(cdr.buf) */
+		close(fd);
+	} else if (errno == ENOENT) {
+		strcpy(hashbuf, NONEXISTENTFLAG);
+	} else {
+		warning(_("%s: unable to open %s to compute its digest: %s"),
+		        pkg_name(pkg, pnaw_nonambig), fn, strerror(errno));
+		strcpy(hashbuf, EMPTYHASHFLAG);
+	}
+}