From fb9377df17ecd0261ac33b79710e96e09fff6c43 Mon Sep 17 00:00:00 2001
From: David Bader <65665893+BunterSchatten@users.noreply.github.com>
Date: Fri, 30 Jan 2026 14:44:38 +0100
Subject: [PATCH] core/os: fix lookup_env_buf only working with empty buffer

---
 core/os/os2/env_linux.odin | 1 +
 core/os/os2/env_posix.odin | 1 +
 core/os/os2/env_wasi.odin  | 1 +
 core/os/os_darwin.odin     | 1 +
 core/os/os_freebsd.odin    | 1 +
 core/os/os_haiku.odin      | 1 +
 core/os/os_linux.odin      | 1 +
 core/os/os_netbsd.odin     | 1 +
 core/os/os_openbsd.odin    | 1 +
 9 files changed, 9 insertions(+)

diff --git a/core/os/os2/env_linux.odin b/core/os/os2/env_linux.odin
index faee5c5ab..7855fbfed 100644
--- a/core/os/os2/env_linux.odin
+++ b/core/os/os2/env_linux.odin
@@ -282,6 +282,7 @@ when ODIN_NO_CRT {
 			return "", .Buffer_Full
 		} else {
 			copy(buf, key)
+			buf[len(key)] = 0
 		}
 
 		cval := posix.getenv(cstring(raw_data(buf)))
diff --git a/core/os/os2/env_posix.odin b/core/os/os2/env_posix.odin
index 8b5f2082e..72a1daf18 100644
--- a/core/os/os2/env_posix.odin
+++ b/core/os/os2/env_posix.odin
@@ -35,6 +35,7 @@ _lookup_env_buf :: proc(buf: []u8, key: string) -> (value: string, error: Error)
 		return "", .Buffer_Full
 	} else {
 		copy(buf, key)
+		buf[len(key)] = 0
 	}
 
 	cval := posix.getenv(cstring(raw_data(buf)))
diff --git a/core/os/os2/env_wasi.odin b/core/os/os2/env_wasi.odin
index b126d014e..cb40667cf 100644
--- a/core/os/os2/env_wasi.odin
+++ b/core/os/os2/env_wasi.odin
@@ -88,6 +88,7 @@ _lookup_env_buf :: proc(buf: []u8, key: string) -> (value: string, error: Error)
 		return "", .Buffer_Full
 	} else {
 		copy(buf, key)
+		buf[len(key)] = 0
 	}
 
 	sync.shared_guard(&g_env_mutex)
diff --git a/core/os/os_darwin.odin b/core/os/os_darwin.odin
index 77b5825dd..d8f7a9577 100644
--- a/core/os/os_darwin.odin
+++ b/core/os/os_darwin.odin
@@ -1072,6 +1072,7 @@ lookup_env_buffer :: proc(buf: []u8, key: string) -> (value: string, err: Error)
 		return "", .Buffer_Full
 	} else {
 		copy(buf, key)
+		buf[len(key)] = 0
 	}
 
 	if value = string(_unix_getenv(cstring(raw_data(buf)))); value == "" {
diff --git a/core/os/os_freebsd.odin b/core/os/os_freebsd.odin
index 0542e10dc..82b5a2f0f 100644
--- a/core/os/os_freebsd.odin
+++ b/core/os/os_freebsd.odin
@@ -844,6 +844,7 @@ lookup_env_buffer :: proc(buf: []u8, key: string) -> (value: string, err: Error)
 		return "", .Buffer_Full
 	} else {
 		copy(buf, key)
+		buf[len(key)] = 0
 	}
 
 	if value = string(_unix_getenv(cstring(raw_data(buf)))); value == "" {
diff --git a/core/os/os_haiku.odin b/core/os/os_haiku.odin
index e7c71338b..ad984e33c 100644
--- a/core/os/os_haiku.odin
+++ b/core/os/os_haiku.odin
@@ -487,6 +487,7 @@ lookup_env_buffer :: proc(buf: []u8, key: string) -> (value: string, err: Error)
 		return "", .Buffer_Full
 	} else {
 		copy(buf, key)
+		buf[len(key)] = 0
 	}
 
 	if value = string(_unix_getenv(cstring(raw_data(buf)))); value == "" {
diff --git a/core/os/os_linux.odin b/core/os/os_linux.odin
index f0f9b401c..4c32676c6 100644
--- a/core/os/os_linux.odin
+++ b/core/os/os_linux.odin
@@ -963,6 +963,7 @@ lookup_env_buffer :: proc(buf: []u8, key: string) -> (value: string, err: Error)
 		return "", .Buffer_Full
 	} else {
 		copy(buf, key)
+		buf[len(key)] = 0
 	}
 
 	if value = string(_unix_getenv(cstring(raw_data(buf)))); value == "" {
diff --git a/core/os/os_netbsd.odin b/core/os/os_netbsd.odin
index 30511012f..640ea46cd 100644
--- a/core/os/os_netbsd.odin
+++ b/core/os/os_netbsd.odin
@@ -891,6 +891,7 @@ lookup_env_buffer :: proc(buf: []u8, key: string) -> (value: string, err: Error)
 		return "", .Buffer_Full
 	} else {
 		copy(buf, key)
+		buf[len(key)] = 0
 	}
 
 	if value = string(_unix_getenv(cstring(raw_data(buf)))); value == "" {
diff --git a/core/os/os_openbsd.odin b/core/os/os_openbsd.odin
index 50ee37dff..bf89a21f4 100644
--- a/core/os/os_openbsd.odin
+++ b/core/os/os_openbsd.odin
@@ -804,6 +804,7 @@ lookup_env_buffer :: proc(buf: []u8, key: string) -> (value: string, err: Error)
 		return "", .Buffer_Full
 	} else {
 		copy(buf, key)
+		buf[len(key)] = 0
 	}
 
 	if value = string(_unix_getenv(cstring(raw_data(buf)))); value == "" {