1 files changed, 323 insertions, 0 deletions
diff --git a/src/lib-storage/index/maildir/maildir-util.c b/src/lib-storage/index/maildir/maildir-util.c
new file mode 100644
index 0000000..c03546e
--- /dev/null
+++ b/src/lib-storage/index/maildir/maildir-util.c
@@ -0,0 +1,323 @@
+/* Copyright (c) 2004-2018 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "array.h"
+#include "ioloop.h"
+#include "str.h"
+#include "mkdir-parents.h"
+#include "mailbox-list-private.h"
+#include "maildir-storage.h"
+#include "maildir-uidlist.h"
+#include "maildir-keywords.h"
+#include "maildir-filename-flags.h"
+#include "maildir-sync.h"
+#include "mailbox-recent-flags.h"
+
+#include <stdio.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <utime.h>
+#include <sys/stat.h>
+
+#define MAILDIR_RESYNC_RETRY_COUNT 10
+
+static const char *
+maildir_filename_guess(struct maildir_mailbox *mbox, uint32_t uid,
+		       const char *fname,
+		       enum maildir_uidlist_rec_flag *uidlist_flags,
+		       bool *have_flags_r)
+
+{
+	struct mail_index_view *view = mbox->flags_view;
+	struct maildir_keywords_sync_ctx *kw_ctx;
+	enum mail_flags flags;
+	ARRAY_TYPE(keyword_indexes) keywords;
+	const char *p;
+	uint32_t seq;
+
+	if (view == NULL || !mail_index_lookup_seq(view, uid, &seq)) {
+		*have_flags_r = FALSE;
+		return fname;
+	}
+
+	t_array_init(&keywords, 32);
+	mail_index_lookup_view_flags(view, seq, &flags, &keywords);
+	if (array_count(&keywords) == 0) {
+		*have_flags_r = (flags & MAIL_FLAGS_NONRECENT) != 0;
+		fname = maildir_filename_flags_set(fname, flags);
+	} else {
+		*have_flags_r = TRUE;
+		kw_ctx = maildir_keywords_sync_init_readonly(mbox->keywords,
+							     mbox->box.index);
+		fname = maildir_filename_flags_kw_set(kw_ctx, fname,
+						      flags, &keywords);
+		maildir_keywords_sync_deinit(&kw_ctx);
+	}
+
+	if (*have_flags_r) {
+		/* don't even bother looking into new/ dir */
+		*uidlist_flags &= MAILDIR_UIDLIST_REC_FLAG_NEW_DIR;
+	} else if ((*uidlist_flags & MAILDIR_UIDLIST_REC_FLAG_MOVED) == 0 &&
+		   ((*uidlist_flags & MAILDIR_UIDLIST_REC_FLAG_NEW_DIR) != 0 ||
+		    mailbox_recent_flags_have_uid(&mbox->box, uid))) {
+		/* probably in new/ dir, drop ":2," from fname */
+		*uidlist_flags |= MAILDIR_UIDLIST_REC_FLAG_NEW_DIR;
+		p = strrchr(fname, MAILDIR_INFO_SEP);
+		if (p != NULL)
+			fname = t_strdup_until(fname, p);
+	}
+
+	return fname;
+}
+
+static int maildir_file_do_try(struct maildir_mailbox *mbox, uint32_t uid,
+			       maildir_file_do_func *callback, void *context)
+{
+	const char *path, *fname;
+	enum maildir_uidlist_rec_flag flags;
+	bool have_flags;
+	int ret;
+
+	ret = maildir_sync_lookup(mbox, uid, &flags, &fname);
+	if (ret <= 0)
+		return ret == 0 ? -2 : -1;
+
+	if ((flags & MAILDIR_UIDLIST_REC_FLAG_NONSYNCED) != 0) {
+		/* let's see if we can guess the filename based on index */
+		fname = maildir_filename_guess(mbox, uid, fname,
+					       &flags, &have_flags);
+	}
+	/* make a copy, just in case callback refreshes uidlist and
+	   the pointer becomes invalid. */
+	fname = t_strdup(fname);
+
+	ret = 0;
+	if ((flags & MAILDIR_UIDLIST_REC_FLAG_NEW_DIR) != 0) {
+		/* probably in new/ dir */
+		path = t_strconcat(mailbox_get_path(&mbox->box),
+				   "/new/", fname, NULL);
+		ret = callback(mbox, path, context);
+	}
+	if (ret == 0) {
+		path = t_strconcat(mailbox_get_path(&mbox->box), "/cur/",
+				   fname, NULL);
+		ret = callback(mbox, path, context);
+	}
+	if (ret > 0 && (flags & MAILDIR_UIDLIST_REC_FLAG_NONSYNCED) != 0) {
+		/* file was found. make sure we remember its latest name. */
+		maildir_uidlist_update_fname(mbox->uidlist, fname);
+	} else if (ret == 0 &&
+		   (flags & MAILDIR_UIDLIST_REC_FLAG_NONSYNCED) == 0) {
+		/* file wasn't found. mark this message nonsynced, so we can
+		   retry the lookup by guessing the flags */
+		maildir_uidlist_add_flags(mbox->uidlist, fname,
+					  MAILDIR_UIDLIST_REC_FLAG_NONSYNCED);
+	}
+	return ret;
+}
+
+static int do_racecheck(struct maildir_mailbox *mbox, const char *path,
+			void *context)
+{
+	const uint32_t *uidp = context;
+	struct stat st;
+	int ret;
+
+	ret = lstat(path, &st);
+	if (ret == 0 && (st.st_mode & S_IFMT) == S_IFLNK) {
+		/* most likely a symlink pointing to a nonexistent file */
+		mailbox_set_critical(&mbox->box,
+			"Maildir: Symlink destination doesn't exist for UID=%u: %s", *uidp, path);
+		return -2;
+	} else if (ret < 0 && errno != ENOENT) {
+		mailbox_set_critical(&mbox->box, "lstat(%s) failed: %m", path);
+		return -1;
+	} else {
+		/* success or ENOENT, either way we're done */
+		mailbox_set_critical(&mbox->box,
+			"maildir_file_do(%s): Filename keeps changing for UID=%u", path, *uidp);
+		return -1;
+	}
+}
+
+#undef maildir_file_do
+int maildir_file_do(struct maildir_mailbox *mbox, uint32_t uid,
+		    maildir_file_do_func *callback, void *context)
+{
+	int i, ret;
+
+	T_BEGIN {
+		ret = maildir_file_do_try(mbox, uid, callback, context);
+	} T_END;
+	if (ret == 0 && mbox->storage->set->maildir_very_dirty_syncs) T_BEGIN {
+		/* try guessing again with refreshed flags */
+		if (maildir_sync_refresh_flags_view(mbox) == 0)
+			ret = maildir_file_do_try(mbox, uid, callback, context);
+	} T_END;
+	for (i = 0; i < MAILDIR_RESYNC_RETRY_COUNT && ret == 0; i++) {
+		/* file is either renamed or deleted. sync the maildir and
+		   see which one. if file appears to be renamed constantly,
+		   don't try to open it more than 10 times. */
+		if (maildir_storage_sync_force(mbox, uid) < 0)
+			return -1;
+
+		T_BEGIN {
+			ret = maildir_file_do_try(mbox, uid, callback, context);
+		} T_END;
+	}
+
+	if (i == MAILDIR_RESYNC_RETRY_COUNT) T_BEGIN {
+		ret = maildir_file_do_try(mbox, uid, do_racecheck, &uid);
+	} T_END;
+
+	return ret == -2 ? 0 : ret;
+}
+
+static int maildir_create_path(struct mailbox *box, const char *path,
+			       enum mailbox_list_path_type type, bool retry)
+{
+	const struct mailbox_permissions *perm = mailbox_get_permissions(box);
+	const char *p, *parent;
+
+	if (mkdir_chgrp(path, perm->dir_create_mode, perm->file_create_gid,
+			perm->file_create_gid_origin) == 0)
+		return 0;
+
+	switch (errno) {
+	case EEXIST:
+		return 0;
+	case ENOENT:
+		p = strrchr(path, '/');
+		if (type == MAILBOX_LIST_PATH_TYPE_MAILBOX ||
+		    p == NULL || !retry) {
+			/* mailbox was being deleted just now */
+			mailbox_set_deleted(box);
+			return -1;
+		}
+		/* create index/control root directory */
+		parent = t_strdup_until(path, p);
+		if (mailbox_list_mkdir_root(box->list, parent, type) < 0) {
+			mail_storage_copy_list_error(box->storage, box->list);
+			return -1;
+		}
+		/* should work now, try again */
+		return maildir_create_path(box, path, type, FALSE);
+	default:
+		mailbox_set_critical(box, "mkdir(%s) failed: %m", path);
+		return -1;
+	}
+}
+
+static int maildir_create_subdirs(struct mailbox *box)
+{
+	static const char *subdirs[] = { "cur", "new", "tmp" };
+	const char *dirs[N_ELEMENTS(subdirs) + 2];
+	enum mailbox_list_path_type types[N_ELEMENTS(subdirs) + 2];
+	struct stat st;
+	const char *path;
+	unsigned int i, count;
+
+	/* @UNSAFE: get a list of directories we want to create */
+	for (i = 0; i < N_ELEMENTS(subdirs); i++) {
+		types[i] = MAILBOX_LIST_PATH_TYPE_MAILBOX;
+		dirs[i] = t_strconcat(mailbox_get_path(box),
+				      "/", subdirs[i], NULL);
+	}
+	if (mailbox_get_path_to(box, MAILBOX_LIST_PATH_TYPE_CONTROL, &path) > 0) {
+		types[i] = MAILBOX_LIST_PATH_TYPE_CONTROL;
+		dirs[i++] = path;
+	}
+	if (mailbox_get_path_to(box, MAILBOX_LIST_PATH_TYPE_INDEX, &path) > 0) {
+		types[i] = MAILBOX_LIST_PATH_TYPE_INDEX;
+		dirs[i++] = path;
+	}
+	count = i;
+	i_assert(count <= N_ELEMENTS(dirs));
+
+	for (i = 0; i < count; i++) {
+		path = dirs[i];
+		if (stat(path, &st) == 0)
+			continue;
+		if (errno != ENOENT) {
+			mailbox_set_critical(box, "stat(%s) failed: %m", path);
+			break;
+		}
+		if (maildir_create_path(box, path, types[i], TRUE) < 0)
+			break;
+	}
+	return i == N_ELEMENTS(dirs) ? 0 : -1;
+}
+
+bool maildir_set_deleted(struct mailbox *box)
+{
+	struct stat st;
+	int ret;
+
+	if (stat(mailbox_get_path(box), &st) < 0) {
+		if (errno == ENOENT)
+			mailbox_set_deleted(box);
+		else {
+			mailbox_set_critical(box,
+				"stat(%s) failed: %m", mailbox_get_path(box));
+		}
+		return FALSE;
+	}
+	/* maildir itself exists. create all of its subdirectories in case
+	   they got lost. */
+	T_BEGIN {
+		ret = maildir_create_subdirs(box);
+	} T_END;
+	return ret < 0 ? FALSE : TRUE;
+}
+
+int maildir_lose_unexpected_dir(struct mail_storage *storage, const char *path)
+{
+	const char *dest, *fname, *p;
+
+	/* There's a directory in maildir, get rid of it.
+
+	   In some installations this was caused by a messed up configuration
+	   where e.g. mails was initially delivered to new/new/ directory.
+	   Also Dovecot v2.0.0 - v2.0.4 sometimes may have renamed tmp/
+	   directory under new/ or cur/. */
+	if (rmdir(path) == 0) {
+		mail_storage_set_critical(storage,
+			"Maildir: rmdir()ed unwanted empty directory: %s",
+			path);
+		return 1;
+	} else if (errno == ENOENT) {
+		/* someone else rmdired or renamed it */
+		return 0;
+	} else if (errno != ENOTEMPTY) {
+		mail_storage_set_critical(storage,
+			"Maildir: Found unwanted directory %s, "
+			"but rmdir() failed: %m", path);
+		return -1;
+	}
+
+	/* It's not safe to delete this directory since it has some files in it,
+	   but it's also not helpful to log this message over and over again.
+	   Get rid of this error by renaming the directory elsewhere */
+	p = strrchr(path, '/');
+	i_assert(p != NULL);
+	fname = p + 1;
+	while (p != path && p[-1] != '/') p--;
+	i_assert(p != NULL);
+
+	dest = t_strconcat(t_strdup_until(path, p), "extra-", fname, NULL);
+	if (rename(path, dest) == 0) {
+		mail_storage_set_critical(storage,
+			"Maildir: renamed unwanted directory %s to %s",
+			path, dest);
+		return 1;
+	} else if (errno == ENOENT) {
+		/* someone else renamed it (could have been flag change) */
+		return 0;
+	} else {
+		mail_storage_set_critical(storage,
+			"Maildir: Found unwanted directory, "
+			"but rename(%s, %s) failed: %m", path, dest);
+		return -1;
+	}
+}