From 5a7a88ccbdfcfc43f80a5f3ee7162203fa1cb8fb Mon Sep 17 00:00:00 2001
From: remittor <remittor@gmail.com>
Date: Fri, 16 Jan 2026 11:34:09 +0300
Subject: [PATCH] luci: Fix save very long textareas to file

---
 .../resources/view/zapret/tools.js            | 56 ++++++++++++-------
 1 file changed, 36 insertions(+), 20 deletions(-)

diff --git a/luci-app-zapret/htdocs/luci-static/resources/view/zapret/tools.js b/luci-app-zapret/htdocs/luci-static/resources/view/zapret/tools.js
index 5751128..61d11c6 100644
--- a/luci-app-zapret/htdocs/luci-static/resources/view/zapret/tools.js
+++ b/luci-app-zapret/htdocs/luci-static/resources/view/zapret/tools.js
@@ -370,40 +370,56 @@ return baseclass.extend({
             ]);
         },
 
-        handleSaveAdv: async function(ev) {
-            let txt = document.getElementById('widget.modal_content');
-            let value = txt.value.trim().replace(/\r\n/g, '\n');
-            if (value.length > 0) {
-                value += '\n';
-            }
-            let data = value.replace(/'/g, `'\"'\"'`);
-            let chunkSize = 8000;
+        writeAdv: async function(fileName, data, chunkSize = 8000)
+        {
+            let tmpFile = fileName + '.tmp';
             try {
-                for (let wsize = -1; wsize < data.length; wsize += chunkSize) {
-                    let chunk = '';
-                    if (wsize < 0) {
-                        wsize = 0;
+                for (let wsize = 0; wsize <= data.length; wsize += chunkSize) {
+                    let chunk = data.slice(wsize, wsize + chunkSize);
+                    if (wsize > 0 && chunk.length == 0) {
+                        break;  // EOF
                     }
-                    if (data.length > 0) {
-                        chunk = data.slice(wsize, wsize + chunkSize);
-                    }
-                    let teeArg = (wsize === 0) ? '' : '-a ';
-                    let cmd = `printf %s '${chunk}' | tee ${teeArg} '${this.file}'`;
+                    chunk = chunk.replace(/'/g, `'\"'\"'`);
+                    let teeArg = (wsize === 0) ? '' : '-a';
+                    let cmd = `printf %s '${chunk}' | tee ${teeArg} '${tmpFile}'`;
                     let res = await fs.exec('/bin/busybox', [ 'sh', '-c', cmd ]);
                     if (res.code !== 0) {
                         throw new Error('tee failed, rc = ' + res.code);
                     }
                 }
+                let res = await fs.exec('/bin/busybox', [ 'mv', '-f', tmpFile, fileName ]);
+                if (res.code != 0) {
+                    throw new Error('mv failed, rc = ' + res.code);
+                }
+            } catch(e) {
+                try {
+                    await fs.exec('/bin/busybox', [ 'rm', '-f', tmpFile ]);
+                } catch(e2) {
+                    // nothing
+                }
+                throw e;
+            }
+            return fs.stat(fileName);
+        },
+
+        handleSaveAdv: async function(ev)
+        {
+            let txt = document.getElementById('widget.modal_content');
+            let value = txt.value.trim().replace(/\r\n/g, '\n');
+            if (value.length > 0) {
+                value += '\n';
+            }
+            return this.writeAdv(this.file, value).then(async rc => {
                 txt.value = value;
                 ui.addNotification(null, E('p', _('Contents have been saved.')), 'info');
                 if (this.callback) {
                     return this.callback(rc);
                 }
-            } catch(e) {
+            }).catch(e => {
                 ui.addNotification(null, E('p', _('Unable to save the contents') + ': %s'.format(e.message)));
-            } finally {
+            }).finally(() => {
                 ui.hideModal();
-            }
+            });
         },
 
         error: function(e) {