diff options
Diffstat (limited to 'src/main/configure.c')
-rw-r--r-- | src/main/configure.c | 829 |
1 files changed, 829 insertions, 0 deletions
diff --git a/src/main/configure.c b/src/main/configure.c new file mode 100644 index 0000000..14f300b --- /dev/null +++ b/src/main/configure.c @@ -0,0 +1,829 @@ +/* + * 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 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_NOCOPY), + pkg, &pkg->installed); + + rc = conffderef(pkg, &cdr, usenode->name); + if (rc == -1) { + conff->hash = EMPTYHASHFLAG; + return; + } + md5hash(pkg, currenthash, cdr.buf); + + varbuf_reset(&cdr2); + varbuf_add_str(&cdr2, cdr.buf); + varbuf_end_str(&cdr2); + /* 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_reset(result); + varbuf_add_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_reset(result); + varbuf_add_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_buf(result, target.buf, target.used); + 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); + } +} |