1 files changed, 124 insertions, 0 deletions
diff --git a/src/utils/common/lookup.h b/src/utils/common/lookup.h
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+/*  Copyright (C) 2022 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+
+    This program 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 3 of the License, or
+    (at your option) any later version.
+
+    This program 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/>.
+ */
+
+#pragma once
+
+#include <histedit.h>
+
+#include "libknot/mm_ctx.h"
+#include "contrib/qp-trie/trie.h"
+
+/*! Lookup context. */
+typedef struct {
+	/*! Memory pool context. */
+	knot_mm_t mm;
+	/*! Main trie storage. */
+	trie_t *trie;
+
+	/*! Current (iteration) data context. */
+	struct {
+		/*! Stored key. */
+		char *key;
+		/*! Corresponding key data. */
+		void *data;
+	} found;
+
+	/*! Iteration context. */
+	struct {
+		/*! Total number of possibilities. */
+		size_t count;
+		/*! The first possibility. */
+		char *first_key;
+		/*! Hat-trie iterator. */
+		trie_it_t *it;
+	} iter;
+} lookup_t;
+
+/*!
+ * Initializes the lookup context.
+ *
+ * \param[in] lookup  Lookup context.
+ *
+ * \return Error code, KNOT_EOK if successful.
+ */
+int lookup_init(lookup_t *lookup);
+
+/*!
+ * Deinitializes the lookup context.
+ *
+ * \param[in] lookup  Lookup context.
+ */
+void lookup_deinit(lookup_t *lookup);
+
+/*!
+ * Inserts given key and data into the lookup.
+ *
+ * \param[in] lookup  Lookup context.
+ * \param[in] str     Textual key.
+ * \param[in] data    Key textual data.
+ *
+ * \return Error code, KNOT_EOK if successful.
+ */
+int lookup_insert(lookup_t *lookup, const char *str, void *data);
+
+/*!
+ * Removes given key from the lookup.
+ *
+ * \param[in] lookup  Lookup context.
+ * \param[in] str     Textual key.
+ *
+ * \return Error code, KNOT_EOK if successful.
+ */
+int lookup_remove(lookup_t *lookup, const char *str);
+
+/*!
+ * Searches the lookup container for the given key.
+ *
+ * \note If one candidate, lookup.found contains the key/data,
+ *       if more candidates, lookup.found contains the common key prefix and
+ *       lookup.iter.first_key is the first candidate key.
+ *
+ * \param[in] lookup   Lookup context.
+ * \param[in] str      Textual key.
+ * \param[in] str_len  Textual key length.
+ *
+ * \return Error code, KNOT_EOK if 1 candidate, KNOT_ENOENT if no candidate,
+ *         and KNOT_EFEWDATA if more candidates are possible.
+ */
+int lookup_search(lookup_t *lookup, const char *str, size_t str_len);
+
+/*!
+ * Moves the lookup iterator to the next key candidate.
+ *
+ * \note lookup.found is updated.
+ *
+ * \param[in] lookup   Lookup context.
+ */
+void lookup_list(lookup_t *lookup);
+
+/*!
+ * Completes the string based on the lookup content or prints all candidates.
+ *
+ * \param[in] lookup     Lookup context.
+ * \param[in] str        Textual key.
+ * \param[in] str_len    Textual key length.
+ * \param[in] el         Editline context.
+ * \param[in] add_space  Add one space after completed string flag.
+ *
+ * \return Error code, same as lookup_search().
+ */
+int lookup_complete(lookup_t *lookup, const char *str, size_t str_len,
+                    EditLine *el, bool add_space);