Run static analysis in CI (#129)

* Run static analysis in CI

* Remove analysis-report in make clean

* Add remark

* Remove the memory helper functions

* Revert "Remove the memory helper functions"

This reverts commit 364234aea02cca38ed40a5bce1bbc8f8eb02aee2.

* Remove swap file

.github/workflows/ckzg-test.yml

@@ -23,6 +23,10 @@ jobs:
         run: |
           cd src
           make test
+      - name: Clang Static Analyzer
+        run: |
+          cd src
+          make analyze
       - name: Install LLVM
         uses: egor-tensin/setup-clang@v1
       - name: Generate coverage report

src/Makefile

@@ -91,10 +91,17 @@ profile: \
 	profile_compute_kzg_proof \
 	profile_compute_aggregate_kzg_proof
 
+.PHONY: analyze
+analyze: c_kzg_4844.c
+	@$(CC) --analyze -Xanalyzer -analyzer-output=html \
+	    -o analysis-report $(CFLAGS) -c $<
+	@[ -d analysis-report ] && exit 1 || exit 0
+
 .PHONY: clean
 clean:
 	@rm -f *.o *.profraw *.profdata *.html xray-log.* *.prof *.pdf \
 	    test_c_kzg_4844 test_c_kzg_4844_cov test_c_kzg_4844_prof
+	@rm -rf analysis-report
 
 .PHONY: format
 format:

src/c_kzg_4844.c

@@ -145,16 +145,15 @@ static const fr_t FR_ONE = {
 /**
  * Wrapped `malloc()` that reports failures to allocate.
  *
+ * @remark Will return C_KZG_BADARGS if the requested size is zero.
+ *
  * @param[out] x Pointer to the allocated space
  * @param[in]  n The number of bytes to be allocated
  */
 static C_KZG_RET c_kzg_malloc(void **x, size_t n) {
-    if (n > 0) {
+    if (n == 0) return C_KZG_BADARGS;
     *x = malloc(n);
     return *x != NULL ? C_KZG_OK : C_KZG_MALLOC;
-    }
-    *x = NULL;
-    return C_KZG_OK;
 }
 
 /**
@@ -564,6 +563,7 @@ static C_KZG_RET bit_reversal_permutation(
 ) {
     CHECK(n >> 32 == 0);
     CHECK(is_power_of_two(n));
+    CHECK(log2_pow2(n) != 0);
 
     // Pointer arithmetic on `void *` is naughty, so cast to something
     // definite
@@ -1601,6 +1601,8 @@ C_KZG_RET load_trusted_setup(
     out->g1_values = NULL;
     out->g2_values = NULL;
 
+    CHECK(n1 > 0);
+    CHECK(n2 > 0);
     ret = new_g1_array(&out->g1_values, n1);
     if (ret != C_KZG_OK) goto out_error;
     ret = new_g2_array(&out->g2_values, n2);