Fix issues accessing object/array fields when the field itself has a …

…null character in it (fix #2176)
espruino · Mar 31, 2022 · 3cc43cd · 3cc43cd
1 parent c8b00c6
commit 3cc43cd
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Showing 4 changed files with 16 additions and 5 deletions.
diff --git a/ChangeLog b/ChangeLog
@@ -47,6 +47,7 @@
             Storage: Now put all .js files into internal storage (if 2 storage areas). Fix corruption issue when reading using file with explicit drive letter 
             Bangle.js: default 'locale' now supports second 'dp' argument for decimal places in distance/speed/temp
             Graphics: Restrict setClipRect coordinates (Except on ST7789_8BIT (Bangle.js 1) where we need it for notifications. This stops potential out of bounds writes is setClipRect is wrong.
+            Fix issues accessing object/array fields when the field itself has a null character in it (fix #2176)
 
      2v12 : nRF52840: Flow control XOFF is now sent at only 3/8th full - delays in BLE mean we can sometimes fill our 1k input buffer otherwise
             __FILE__ is now set correctly for apps (fixes 2v11 regression)

diff --git a/src/jslex.c b/src/jslex.c
@@ -932,8 +932,7 @@ JsVar *jslGetTokenValueAsVar() {
     return jsvNewFromString(jslReservedWordAsString(lex->tk));
   } else {
     assert(lex->tokenl < JSLEX_MAX_TOKEN_LENGTH);
-    lex->token[lex->tokenl]  = 0; // add final null
-    return jsvNewFromString(lex->token);
+    return jsvNewStringOfLength(lex->tokenl, lex->token);
   }
 }
 

diff --git a/src/jsvar.c b/src/jsvar.c
@@ -1210,18 +1210,21 @@ bool jsvIsBasicVarEqual(JsVar *a, JsVar *b) {
       }
     }
   } else if (jsvIsString(a) && jsvIsString(b)) {
+    // OPT: could we do a fast check here with data?
     JsvStringIterator ita, itb;
     jsvStringIteratorNew(&ita, a, 0);
     jsvStringIteratorNew(&itb, b, 0);
     while (true) {
-      char a = jsvStringIteratorGetCharAndNext(&ita);
-      char b = jsvStringIteratorGetCharAndNext(&itb);
+      int a = jsvStringIteratorGetCharOrMinusOne(&ita);
+      jsvStringIteratorNext(&ita);
+      int b = jsvStringIteratorGetCharOrMinusOne(&itb);
+      jsvStringIteratorNext(&itb);
       if (a != b) {
         jsvStringIteratorFree(&ita);
         jsvStringIteratorFree(&itb);
         return false;
       }
-      if (!a) { // equal, but end of string
+      if (a < 0) { // equal, but end of string
         jsvStringIteratorFree(&ita);
         jsvStringIteratorFree(&itb);
         return true;

diff --git a/tests/test_object_zero_in_keys.js b/tests/test_object_zero_in_keys.js
@@ -0,0 +1,8 @@
+// https://github.com/espruino/Espruino/issues/2176
+
+a = { "" : {}, " \x00hello" : "world" }
+a["\x00abc"] = "foo"
+a[" \x00abc"] = "bar"
+
+json = JSON.stringify(a)
+result = json == "{\"\":{},\" \\u0000hello\":\"world\",\"\\u0000abc\":\"foo\",\" \\u0000abc\":\"bar\"}";