From 73b3ce068d86b1c9e72a92d3d8a95c17b499116d Mon Sep 17 00:00:00 2001
From: Egor <egor@patchysicp.xyz>
Date: Thu, 22 Jan 2026 16:43:14 +0200
Subject: [PATCH] map: add case-insensitive look up

---
 src/irc.cpp | 22 ++++------------------
 src/map.cpp | 25 ++++++++++++++++++++++---
 src/map.hpp | 10 ++++++++--
 3 files changed, 34 insertions(+), 23 deletions(-)

diff --git a/src/irc.cpp b/src/irc.cpp
index 97dd0a0..29b111f 100644
--- a/src/irc.cpp
+++ b/src/irc.cpp
@@ -1785,23 +1785,9 @@ void channel_topic(Client *src, Channel *chan, const char *topic, const char *wh
 	chanlog_time(chan->topic_when);
 	sendbuf_chan(chan);
 }
-Client *findClient(const char *nickname)
-{
-	char key[MAX_NICKLEN];
-	size_t len = strlen(nickname);
-	if (len >= MAX_NICKLEN)
-		return NULL;
-	memcpy(key, nickname, len+1);
-	stringlower(key);
-	return client_map.get(key);
+Client *findClient(const char *nickname) {
+	return client_map.iget(nickname);
 }
-Channel *findChannel(const char *channel)
-{
-	size_t chanlen = strlen(channel);
-	if (chanlen >= MAX_CHANLEN)
-		return NULL;
-	char key[MAX_CHANLEN];
-	memcpy(key, channel, chanlen+1);
-	stringlower(key);
-	return channel_map.get(key);
+Channel *findChannel(const char *channel) {
+	return channel_map.iget(channel);
 }
diff --git a/src/map.cpp b/src/map.cpp
index 2463ccc..721eccf 100644
--- a/src/map.cpp
+++ b/src/map.cpp
@@ -1,13 +1,26 @@
-// Copyright (c) 2023, 2025 Egor
+// Copyright (c) 2023, 2025-2026 Egor
 // SPDX-License-Identifier: GPL-2.0-or-later
 #include "common.hpp"
 #include "map.hpp"
 #include "ircdata.hpp"
+static int istrcmp(const char *a, const char *b) {
+	unsigned char cha, chb;
+	int diff;
+	do {
+		cha = *a++;
+		chb = *b++;
+		if (chb >= 'A' && chb <= 'Z')
+			chb |= 0x20;
+		diff = cha - chb;
+	} while (!diff && cha && chb);
+	return diff;
+}
+template<auto cmp=strcmp>
 static size_t ent_find(map_base *root, const char *key, int *found)
 {
 	auto it = std::partition_point(root->ptr, root->ptr + root->len,
-			[key](const auto &p){ return strcmp(p.key, key) < 0; });
-	*found = it != root->ptr + root->len && !strcmp(it->key, key);
+			[key](const auto &p){ return cmp(p.key, key) < 0; });
+	*found = it != root->ptr + root->len && !cmp(it->key, key);
 	return it - root->ptr;
 }
 void *map_base::_get(const char *key)
@@ -16,6 +29,12 @@ void *map_base::_get(const char *key)
 	size_t i = ent_find(this, key, &found);
 	return found ? ptr[i].value : 0;
 }
+void *map_base::_iget(const char *key)
+{
+	int found;
+	size_t i = ent_find<istrcmp>(this, key, &found);
+	return found ? ptr[i].value : 0;
+}
 void map_base::_set(const char *key, const void *value, void **oldvalue)
 {
 	int found;
diff --git a/src/map.hpp b/src/map.hpp
index 86e7bc7..3f26a96 100644
--- a/src/map.hpp
+++ b/src/map.hpp
@@ -1,4 +1,4 @@
-// Copyright (c) 2023, 2025 Egor
+// Copyright (c) 2023, 2025-2026 Egor
 // SPDX-License-Identifier: GPL-2.0-or-later
 #ifndef MAP_H_
 #define MAP_H_
@@ -24,6 +24,8 @@ struct map_base {
 	/* Return the associated value for a given key.
 	 * Dynarr complexity: O(log n) */
 	void *_get(const char *key);
+	/* _get() but lowercase the key */
+	void *_iget(const char *key);
 	/* Associate a new value with a given key.
 	 * If oldvalue is not NULL, it receives the old value of key.
 	 * No allocation failures on value = NULL.
@@ -103,7 +105,10 @@ public:
 	}
 
 	V get(const char *k) {
-		return (V)_get(k);
+		return static_cast<V>(_get(k));
+	}
+	V iget(const char *k) {
+		return static_cast<V>(_iget(k));
 	}
 };
 
@@ -128,6 +133,7 @@ protected:
 	}
 public:
 	const char *get(const char *k) = delete;
+	const char *iget(const char *k) = delete;
 };
 
 #endif
-- 
2.56.0