1 /* $NetBSD: ntp_assert.h,v 1.6 2020/05/25 20:47:19 christos Exp $ */ 2 3 /* 4 * ntp_assert.h - design by contract stuff 5 * 6 * example: 7 * 8 * int foo(char *a) { 9 * int result; 10 * int value; 11 * 12 * REQUIRE(a != NULL); 13 * ... 14 * bar(&value); 15 * INSIST(value > 2); 16 * ... 17 * 18 * ENSURE(result != 12); 19 * return result; 20 * } 21 * 22 * open question: when would we use INVARIANT()? 23 * 24 * For cases where the overhead for non-debug builds is deemed too high, 25 * use DEBUG_REQUIRE(), DEBUG_INSIST(), DEBUG_ENSURE(), and/or 26 * DEBUG_INVARIANT(). 27 */ 28 29 #ifndef NTP_ASSERT_H 30 #define NTP_ASSERT_H 31 32 # ifdef CALYSTO 33 /* see: http://www.domagoj-babic.com/index.php/ResearchProjects/Calysto */ 34 35 extern void calysto_assume(unsigned char cnd); /* assume this always holds */ 36 extern void calysto_assert(unsigned char cnd); /* check whether this holds */ 37 #define ALWAYS_REQUIRE(x) calysto_assert(x) 38 #define ALWAYS_INSIST(x) calysto_assume(x) /* DLH calysto_assert()? */ 39 #define ALWAYS_INVARIANT(x) calysto_assume(x) 40 #define ALWAYS_ENSURE(x) calysto_assert(x) 41 42 /* # elif defined(__COVERITY__) */ 43 /* 44 * DH: try letting coverity scan our actual assertion macros, now that 45 * isc_assertioncallback_t is marked __attribute__ __noreturn__. 46 */ 47 48 /* 49 * Coverity has special knowledge that assert(x) terminates the process 50 * if x is not true. Rather than teach it about our assertion macros, 51 * just use the one it knows about for Coverity Prevent scans. This 52 * means our assertion code (and ISC's) escapes Coverity analysis, but 53 * that seems to be a reasonable trade-off. 54 */ 55 56 /* 57 #define ALWAYS_REQUIRE(x) assert(x) 58 #define ALWAYS_INSIST(x) assert(x) 59 #define ALWAYS_INVARIANT(x) assert(x) 60 #define ALWAYS_ENSURE(x) assert(x) 61 */ 62 63 64 #elif defined(__FLEXELINT__) 65 66 #include <assert.h> 67 68 #define ALWAYS_REQUIRE(x) assert(x) 69 #define ALWAYS_INSIST(x) assert(x) 70 #define ALWAYS_INVARIANT(x) assert(x) 71 #define ALWAYS_ENSURE(x) assert(x) 72 73 # else /* neither Calysto, Coverity or FlexeLint */ 74 75 #include "isc/assertions.h" 76 77 #define ALWAYS_REQUIRE(x) ISC_REQUIRE(x) 78 #define ALWAYS_INSIST(x) ISC_INSIST(x) 79 #define ALWAYS_INVARIANT(x) ISC_INVARIANT(x) 80 #define ALWAYS_ENSURE(x) ISC_ENSURE(x) 81 82 # endif /* neither Coverity nor Calysto */ 83 84 #define REQUIRE(x) ALWAYS_REQUIRE(x) 85 #define INSIST(x) ALWAYS_INSIST(x) 86 #define INVARIANT(x) ALWAYS_INVARIANT(x) 87 #define ENSURE(x) ALWAYS_ENSURE(x) 88 89 /* 90 * We initially used NTP_REQUIRE() instead of REQUIRE() etc, but that 91 * is unneccesarily verbose, as libisc use of REQUIRE() etc shows. 92 */ 93 94 # ifdef DEBUG 95 #define DEBUG_REQUIRE(x) REQUIRE(x) 96 #define DEBUG_INSIST(x) INSIST(x) 97 #define DEBUG_INVARIANT(x) INVARIANT(x) 98 #define DEBUG_ENSURE(x) ENSURE(x) 99 # else 100 #define DEBUG_REQUIRE(x) do {} while (FALSE) 101 #define DEBUG_INSIST(x) do {} while (FALSE) 102 #define DEBUG_INVARIANT(x) do {} while (FALSE) 103 #define DEBUG_ENSURE(x) do {} while (FALSE) 104 # endif 105 106 #endif /* NTP_ASSERT_H */ 107