From 64f336d6f299d9169a310624b578943723ea08ee Mon Sep 17 00:00:00 2001
From: cnc <cnc@localhost>
Date: Sat, 6 Jun 2026 12:48:33 +0800
Subject: [PATCH] =?UTF-8?q?=E6=8C=89=E6=BA=90=E9=AA=8C=E8=AF=81tooldata?=
 =?UTF-8?q?=E4=BD=8E=E7=B4=A2=E5=BC=95=E5=86=99=E5=85=A5?=
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源依据：LinuxCNC src/emc/tooldata/tooldata_mmap.cc 的 tooldata_put() 仅在 idx > last_index 时返回 IDX_NEW 并更新 last_index，否则返回 IDX_OK。

结论：wasm-safe tooldata mmap probe 增加低于当前 last_index 的写入断言，确认返回 IDX_OK、last_index 不变且数据可读回，减少 tooldata_mmap 后端替换风险。

检查：./test-linuxcnc-wasm-tooldata-link.sh；./test-native.sh；./test-linuxcnc-source-link.sh。
---
 core/wasm_shims/tooldata/tooldata_probe_main.cc | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/core/wasm_shims/tooldata/tooldata_probe_main.cc b/core/wasm_shims/tooldata/tooldata_probe_main.cc
index 9c8da76..d5a61b4 100644
--- a/core/wasm_shims/tooldata/tooldata_probe_main.cc
+++ b/core/wasm_shims/tooldata/tooldata_probe_main.cc
@@ -272,6 +272,23 @@ int main() {
     if (tooldata_put(tool, 12) != IDX_NEW) {
         return 2;
     }
+    CANON_TOOL_TABLE lower_index_tool = tooldata_entry_init();
+    lower_index_tool.toolno = 3;
+    lower_index_tool.pocketno = 5;
+    // LinuxCNC src/emc/tooldata/tooldata_mmap.cc returns IDX_OK for writes at
+    // or below the current last_index and leaves last_index unchanged.
+    if (tooldata_put(lower_index_tool, 5) != IDX_OK) {
+        return 80;
+    }
+    if (tooldata_last_index_get() != 12) {
+        return 81;
+    }
+    CANON_TOOL_TABLE lower_index_loaded = tooldata_entry_init();
+    if (tooldata_get(&lower_index_loaded, 5) != IDX_OK ||
+        lower_index_loaded.toolno != 3 ||
+        lower_index_loaded.pocketno != 5) {
+        return 82;
+    }
 
     CANON_TOOL_TABLE loaded = tooldata_entry_init();
     if (tooldata_get(&loaded, 12) != IDX_OK) {