Don't flush strings from keepGoing

src/parser3.h

@@ -491,6 +491,9 @@ inline PRESERVE_NONE WeaselJsonStatus n_string2(Parser3 *self, char *buf,
     self->flushString(true);
     ++buf;
     self->pop();
+    if (buf == bufEnd) {
+      return WeaselJson_AGAIN;
+    }
     MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
   case '\\':
     ++buf;
@@ -498,6 +501,10 @@ inline PRESERVE_NONE WeaselJsonStatus n_string2(Parser3 *self, char *buf,
       if (auto s = self->push({N_STRING_FOLLOWING_ESCAPE})) {
         return s;
       }
+      if (buf == bufEnd) {
+        self->flushString(false);
+        return WeaselJson_AGAIN;
+      }
       MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
     } else {
       if (*buf == 'u') {
@@ -584,7 +591,7 @@ inline PRESERVE_NONE WeaselJsonStatus n_string_following_escape(Parser3 *self,
   case 't':
     *self->writeBuf++ = tables.unescape[uint8_t(*buf++)];
     self->pop();
-    MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
+    break;
   case 'u':
     ++buf;
     self->utf8Codepoint = 0;
@@ -592,10 +599,15 @@ inline PRESERVE_NONE WeaselJsonStatus n_string_following_escape(Parser3 *self,
     if (auto s = self->push({T_HEX, T_HEX, T_HEX, T_HEX2})) {
       return s;
     }
-    MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
+    break;
   default:
     [[unlikely]] return WeaselJson_REJECT;
   }
+  if (buf == bufEnd) {
+    self->flushString(false);
+    return WeaselJson_AGAIN;
+  }
+  MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
 }
 
 inline PRESERVE_NONE WeaselJsonStatus t_hex(Parser3 *self, char *buf,
@@ -611,6 +623,10 @@ inline PRESERVE_NONE WeaselJsonStatus t_hex(Parser3 *self, char *buf,
   self->utf8Codepoint |= hexVal;
   ++buf;
   self->pop();
+  if (buf == bufEnd) {
+    self->flushString(false);
+    return WeaselJson_AGAIN;
+  }
   MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
 }
 
@@ -658,6 +674,10 @@ inline PRESERVE_NONE WeaselJsonStatus t_hex2(Parser3 *self, char *buf,
               self->push({T_BACKSLASH, T_U2, T_HEX, T_HEX, T_HEX, T_HEX3})) {
         return s;
       }
+      if (buf == bufEnd) {
+        self->flushString(false);
+        return WeaselJson_AGAIN;
+      }
       MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
     }
     bool useTmp = buf - self->writeBuf < 3;
@@ -678,6 +698,10 @@ inline PRESERVE_NONE WeaselJsonStatus t_hex2(Parser3 *self, char *buf,
   }
 
   self->pop();
+  if (buf == bufEnd) {
+    self->flushString(false);
+    return WeaselJson_AGAIN;
+  }
   MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
 }
 
@@ -729,9 +753,33 @@ inline PRESERVE_NONE WeaselJsonStatus t_hex3(Parser3 *self, char *buf,
   }
 
   self->pop();
+  if (buf == bufEnd) {
+    self->flushString(false);
+    return WeaselJson_AGAIN;
+  }
   MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
 }
 
+template <char kChar>
+inline PRESERVE_NONE WeaselJsonStatus singleCharInString(Parser3 *self,
+                                                         char *buf,
+                                                         char *bufEnd) {
+  if (buf == bufEnd) [[unlikely]] {
+    return WeaselJson_REJECT;
+  }
+  if (*buf == kChar) {
+    ++buf;
+    self->pop();
+    if (buf == bufEnd) {
+      self->flushString(false);
+      return WeaselJson_AGAIN;
+    }
+    MUSTTAIL return Parser3::keepGoing(self, buf, bufEnd);
+  } else [[unlikely]] {
+    return WeaselJson_REJECT;
+  }
+}
+
 inline PRESERVE_NONE WeaselJsonStatus n_true(Parser3 *self, char *buf,
                                              char *bufEnd) {
   if (buf == bufEnd) [[unlikely]] {
@@ -829,7 +877,7 @@ constexpr inline struct ContinuationTable {
     continuations[N_NULL] = n_null;
     continuations[T_R] = singleChar<'r'>;
     continuations[T_U] = singleChar<'u'>;
-    continuations[T_U2] = singleChar<'u'>;
+    continuations[T_U2] = singleCharInString<'u'>;
     continuations[T_A] = singleChar<'a'>;
     continuations[T_L] = singleChar<'l'>;
     continuations[T_S] = singleChar<'s'>;
@@ -838,7 +886,7 @@ constexpr inline struct ContinuationTable {
     continuations[T_HEX2] = t_hex2;
     continuations[T_HEX3] = t_hex3;
     continuations[T_EOF] = t_eof;
-    continuations[T_BACKSLASH] = singleChar<'\\'>;
+    continuations[T_BACKSLASH] = singleCharInString<'\\'>;
 
     symbolNames[N_VALUE] = "n_value";
     symbolNames[N_OBJECT2] = "n_object2";
@@ -875,40 +923,6 @@ inline PRESERVE_NONE WeaselJsonStatus Parser3::keepGoing(Parser3 *self,
                                                          char *bufEnd) {
   if (bufEnd - buf == 0) {
     if (!self->complete) {
-      switch (self->top()) {
-      case N_STRING2:
-      case N_STRING_FOLLOWING_ESCAPE:
-      case T_HEX:
-      case T_HEX2:
-      case T_HEX3:
-      case T_BACKSLASH:
-      case T_U2:
-        self->flushString(false);
-        break;
-      case N_STRING: // The beginning of the string is in the future in this
-                     // state. There's no data to flush yet
-      case N_VALUE:
-      case N_OBJECT2:
-      case N_OBJECT3:
-      case N_ARRAY2:
-      case N_ARRAY3:
-      case N_WHITESPACE:
-      case N_NUMBER:
-      case N_TRUE:
-      case N_FALSE:
-      case N_NULL:
-      case T_R:
-      case T_U:
-      case T_A:
-      case T_L:
-      case T_S:
-      case T_COLON:
-      case T_EOF:
-      case N_SYMBOL_COUNT:
-        break;
-      default:
-        __builtin_unreachable();
-      }
       return WeaselJson_AGAIN;
     }
   }