From 842ab2f129cd9fa19f74a648e147de3fd09986f5 Mon Sep 17 00:00:00 2001
From: Randy Lai <randy.cs.lai@gmail.com>
Date: Sat, 22 Apr 2023 19:01:15 -0700
Subject: [PATCH] fix rchk check

---
 src/deque.c          | 10 ++++++----
 src/dict.c           |  6 ++++--
 src/priority_queue.c | 31 ++++++++++++++++++++-----------
 src/xxh.c            |  6 +++++-
 4 files changed, 35 insertions(+), 18 deletions(-)

diff --git a/src/deque.c b/src/deque.c
index 171ecbe..394121f 100644
--- a/src/deque.c
+++ b/src/deque.c
@@ -135,12 +135,13 @@ SEXP deque_remove(SEXP self, SEXP value) {
     SEXP last_ptr = PROTECT(get_sexp_value(self, "last"));
     // make sure the pointers are resolved after serialization/unserialization
     get_last_cons(q, last_ptr);
-    SEXP v, nextq, prev_ptr;
+    SEXP v, v1, nextq, prev_ptr;
     while (q != R_NilValue) {
         v = CAR(q);
+        v1 = PROTECT(VECTOR_ELT(v, 1));
         nextq = CDR(q);
-        if (R_compute_identical(VECTOR_ELT(v, 1), value, 16)) {
-            prev_ptr = VECTOR_ELT(v, 0);
+        if (R_compute_identical(v1, value, 16)) {
+            prev_ptr = PROTECT(VECTOR_ELT(v, 0));
             if (nextq == R_NilValue && prev_ptr == R_NilValue) {
                 set_sexp_value(self, "q", R_NilValue);
                 R_SetExternalPtrAddr(last_ptr, NULL);
@@ -158,9 +159,10 @@ SEXP deque_remove(SEXP self, SEXP value) {
                 SETCDR(prev, nextq);
                 SET_VECTOR_ELT(CAR(nextq), 0, prev_ptr);
             }
-            UNPROTECT(2);
+            UNPROTECT(4);
             return R_NilValue;
         }
+        UNPROTECT(1);
         q = nextq;
     }
     UNPROTECT(2);
diff --git a/src/dict.c b/src/dict.c
index a6e3742..ae3f5cc 100644
--- a/src/dict.c
+++ b/src/dict.c
@@ -176,8 +176,10 @@ SEXP dict_get(SEXP self, SEXP _key) {
         }
         UNPROTECT(1);
     }
-    SEXP vs = get_sexp_value(self, "vs");
-    return VECTOR_ELT(vs, index - 1);
+    SEXP vs = PROTECT(get_sexp_value(self, "vs"));
+    SEXP res = VECTOR_ELT(vs, index - 1);
+    UNPROTECT(1);
+    return res;
 }
 
 
diff --git a/src/priority_queue.c b/src/priority_queue.c
index 1976b36..fe844b0 100644
--- a/src/priority_queue.c
+++ b/src/priority_queue.c
@@ -7,17 +7,20 @@
 
 
 static void swap(SEXP h, int a, int b) {
-    SEXP temp = PROTECT(VECTOR_ELT(h, a));
-    SET_VECTOR_ELT(h, a, VECTOR_ELT(h, b));
-    SET_VECTOR_ELT(h, b, temp);
-    UNPROTECT(1);
+    SEXP ha = PROTECT(VECTOR_ELT(h, a));
+    SEXP hb = PROTECT(VECTOR_ELT(h, b));
+    SET_VECTOR_ELT(h, a, hb);
+    SET_VECTOR_ELT(h, b, ha);
+    UNPROTECT(2);
 }
 
 static int cmp(SEXP h, int a, int b) {
-    SEXP _x = VECTOR_ELT(h, a);
-    SEXP _y = VECTOR_ELT(h, b);
+    PROTECT(h);
+    SEXP _x = PROTECT(VECTOR_ELT(h, a));
+    SEXP _y = PROTECT(VECTOR_ELT(h, b));
     double x = Rf_asReal(VECTOR_ELT(_x, 0));
     double y = Rf_asReal(VECTOR_ELT(_y, 0));
+    UNPROTECT(3);
     return x < y;
 }
 
@@ -33,7 +36,9 @@ static void grow(SEXP self, int n) {
     } else if (m < n + 1) {
         h2 = PROTECT(Rf_allocVector(VECSXP, (int) ceil(GROW_FACTOR * m)));
         for (i = 0; i < n; i++) {
-            SET_VECTOR_ELT(h2, i, VECTOR_ELT(h, i));
+            SEXP h2i = PROTECT(VECTOR_ELT(h, i));
+            SET_VECTOR_ELT(h2, i, h2i);
+            UNPROTECT(1);
         }
         set_sexp_value(self, "h", h2);
         UNPROTECT(1);
@@ -50,7 +55,9 @@ static void shrink(SEXP self, int n) {
     if (n < m1 && m1 > INITIAL_SIZE) {
         h2 = PROTECT(Rf_allocVector(VECSXP, m1));
         for (i = 0; i < n; i++) {
-            SET_VECTOR_ELT(h2, i, VECTOR_ELT(h, i));
+            SEXP h2i = PROTECT(VECTOR_ELT(h, i));
+            SET_VECTOR_ELT(h2, i, h2i);
+            UNPROTECT(1);
         }
         set_sexp_value(self, "h", h2);
         UNPROTECT(1);
@@ -120,11 +127,13 @@ SEXP heap_pop(SEXP self) {
     int n = Rf_asInteger(_n);
     if (n == 0) Rf_error("queue is empty");
     SEXP x = PROTECT(VECTOR_ELT(h, 0));
-    SET_VECTOR_ELT(h, 0, VECTOR_ELT(h, n - 1));
+    SEXP h0 = PROTECT(VECTOR_ELT(h, n - 1));
+    SET_VECTOR_ELT(h, 0, h0);
     sift_down(h, 0, n - 2);
     _n = PROTECT(Rf_ScalarInteger(n - 1));
     set_sexp_value(self, "n", _n);
     shrink(self, n);
-    UNPROTECT(4);
-    return VECTOR_ELT(x, 1);
+    SEXP res = PROTECT(VECTOR_ELT(x, 1));
+    UNPROTECT(6);
+    return res;
 }
diff --git a/src/xxh.c b/src/xxh.c
index f67f631..87a7f0e 100644
--- a/src/xxh.c
+++ b/src/xxh.c
@@ -12,10 +12,14 @@ int is_hashable(SEXP key) {
     } else if (TYPEOF(key) == VECSXP) {
         R_xlen_t i;
         R_xlen_t n = Rf_length(key);
+        SEXP keyi;
         for (i = 0; i < n; i++) {
-            if (!is_hashable(VECTOR_ELT(key, i))) {
+            keyi = PROTECT(VECTOR_ELT(key, i));
+            if (!is_hashable(keyi)) {
+                UNPROTECT(1);
                 return 0;
             }
+            UNPROTECT(1);
         }
         if (!is_hashable(ATTRIB(key))) {
             return 0;