CDRIVER-4822 clean up warnings in public headers (#1751)

* add public-header-warnings target

* add build cmd to compile scripts

* add more flags

* -Wunsafe-buffer-usage fixes

* -Wdocumentation fix

* -Wpadded fixes

* -Wcovered-switch-default fixes

* -Wcast-qual fix

* -Watomic-implicit-seq-cst fix

* MSVC padding

* update flags

* moving macros to bson-macros.h

* clang format fix

* Update bson-oid.h

* rename from MC_* to BSON_*

* add -Wno-padded instead of macro

* move local macros to bson-atomic.h

* minor evg and build fixes

---------

Co-authored-by: Kevin Albertson <[email protected]>

Author: joshbsiegel

.evergreen/scripts/compile-unix.sh

@@ -216,3 +216,8 @@ build_dir="cmake-build"
 
 # Also validate examples.
 "${cmake_binary}" --build "${build_dir:?}" --target mongo_c_driver_examples
+
+if [[ "$EXTRA_CONFIGURE_FLAGS" != *"ENABLE_MONGOC=OFF"* ]]; then
+  # Check public headers for extra warnings.
+  "${cmake_binary}" --build "${build_dir:?}" --target public-header-warnings
+fi

.evergreen/scripts/compile-windows.sh

@@ -143,3 +143,8 @@ fi
 
 # Also validate examples.
 "${cmake_binary:?}" --build "${build_dir:?}" --config "${build_config:?}" --target mongo_c_driver_examples
+
+if [[ "$EXTRA_CONFIGURE_FLAGS" != *"ENABLE_MONGOC=OFF"* ]]; then
+  # Check public headers for extra warnings.
+  "${cmake_binary:?}" --build "${build_dir:?}" --config "${build_config:?}" --target public-header-warnings
+fi

src/CMakeLists.txt

@@ -19,3 +19,27 @@ if (CMAKE_CXX_COMPILER)
       target_link_libraries (mongoc-cxx-check PRIVATE mongoc_shared)
    endif ()
 endif ()
+
+# public-header-warnings
+add_executable(public-header-warnings EXCLUDE_FROM_ALL ${CMAKE_CURRENT_SOURCE_DIR}/c-check.c)
+
+if (TARGET mongoc_static)
+   target_link_libraries(public-header-warnings PRIVATE mongoc_static)
+else ()
+   target_link_libraries(public-header-warnings PRIVATE mongoc_shared)
+endif ()
+
+target_compile_options(public-header-warnings PRIVATE
+  $<$<C_COMPILER_ID:AppleClang,Clang>:-Weverything>
+  $<$<C_COMPILER_ID:GNU>:-Wextra>
+  $<$<C_COMPILER_ID:AppleClang,Clang,GNU>:-Werror>
+  $<$<C_COMPILER_ID:AppleClang,Clang,GNU>:-Wno-declaration-after-statement>
+  $<$<C_COMPILER_ID:AppleClang,Clang,GNU>:-Wno-disabled-macro-expansion>
+  $<$<C_COMPILER_ID:AppleClang,Clang>:-Wno-padded>
+  $<$<C_COMPILER_ID:AppleClang,Clang>:-Wno-reserved-identifier>
+  $<$<C_COMPILER_ID:AppleClang,Clang>:-Wno-documentation-unknown-command>
+  $<$<C_COMPILER_ID:AppleClang,Clang>:-Wno-unknown-warning-option>
+  $<$<C_COMPILER_ID:MSVC>:/W4>
+  $<$<C_COMPILER_ID:MSVC>:/WX>
+  $<$<C_COMPILER_ID:MSVC>:/wd4324>
+)

src/c-check.c

@@ -0,0 +1,8 @@
+#include <bson/bson.h>
+#include <mongoc/mongoc.h>
+
+int
+main (void)
+{
+   return 0;
+}

src/libbson/src/bson/bson-atomic.h

@@ -97,6 +97,34 @@ enum BSON_GNUC_DEPRECATED bson_memory_order {
 #define BSON_EMULATE_PTR
 #endif
 
+// Disable the -Wcovered-switch-default warning.
+#define BSON_DISABLE_COVERED_SWITCH_DEFAULT_BEGIN
+#define BSON_DISABLE_COVERED_SWITCH_DEFAULT_END
+#if defined(__clang__)
+#if __has_warning("-Wcovered-switch-default")
+#undef BSON_DISABLE_COVERED_SWITCH_DEFAULT_BEGIN
+#undef BSON_DISABLE_COVERED_SWITCH_DEFAULT_END
+#define BSON_DISABLE_COVERED_SWITCH_DEFAULT_BEGIN \
+   _Pragma ("clang diagnostic push") _Pragma ("clang diagnostic ignored \"-Wcovered-switch-default\"")
+#define BSON_DISABLE_COVERED_SWITCH_DEFAULT_END _Pragma ("clang diagnostic pop")
+#endif // __has_warning("-Wcovered-switch-default")
+#endif // defined(__clang__)
+
+// Disable the -Watomic-implicit-seq-cst warning.
+#define BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_BEGIN
+#define BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_END
+#if defined(__clang__)
+#if __has_warning("-Watomic-implicit-seq-cst")
+#undef BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_BEGIN
+#undef BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_END
+#define BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_BEGIN \
+   _Pragma ("clang diagnostic push") _Pragma ("clang diagnostic ignored \"-Watomic-implicit-seq-cst\"")
+#define BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_END _Pragma ("clang diagnostic pop")
+#endif // __has_warning("-Watomic-implicit-seq-cst")
+#endif // defined(__clang__)
+
+BSON_DISABLE_COVERED_SWITCH_DEFAULT_BEGIN
+
 #define DEF_ATOMIC_OP(MSVC_Intrinsic, GNU_Intrinsic, GNU_Legacy_Intrinsic, Order, ...)                  \
    do {                                                                                                 \
       switch (Order) {                                                                                  \
@@ -582,7 +610,13 @@ bson_atomic_ptr_compare_exchange_weak (void *volatile *ptr, void *expect, void *
 static BSON_INLINE void *BSON_GNUC_DEPRECATED
 bson_atomic_ptr_fetch (void *volatile const *ptr, enum bson_memory_order ord)
 {
-   return bson_atomic_ptr_compare_exchange_strong ((void *volatile *) ptr, NULL, NULL, ord);
+   // Use a union to address cast-qual compilation warning
+   union {
+      void *volatile const *const_ptr;
+      void *volatile *non_const_ptr;
+   } u;
+   u.const_ptr = ptr;
+   return bson_atomic_ptr_compare_exchange_strong (u.non_const_ptr, NULL, NULL, ord);
 }
 
 #undef DECL_ATOMIC_STDINT
@@ -599,7 +633,11 @@ static BSON_INLINE void BSON_GNUC_DEPRECATED
 bson_atomic_thread_fence (void)
 {
    BSON_IF_MSVC (MemoryBarrier ();)
+
+   BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_BEGIN
    BSON_IF_GNU_LIKE (__sync_synchronize ();)
+   BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_END
+
    BSON_IF_GNU_LEGACY_ATOMICS (__sync_synchronize ();)
 }
 
@@ -619,10 +657,16 @@ BSON_EXPORT (int32_t) bson_atomic_int_add (volatile int32_t *p, int32_t n);
 BSON_GNUC_DEPRECATED
 BSON_EXPORT (int64_t) bson_atomic_int64_add (volatile int64_t *p, int64_t n);
 
+BSON_DISABLE_COVERED_SWITCH_DEFAULT_END
 
 #undef BSON_EMULATE_PTR
 #undef BSON_EMULATE_INT32
 #undef BSON_EMULATE_INT
+#undef BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_BEGIN
+#undef BSON_DISABLE_ATOMIC_IMPLICIT_SEQ_CST_END
+#undef BSON_DISABLE_COVERED_SWITCH_DEFAULT_BEGIN
+#undef BSON_DISABLE_COVERED_SWITCH_DEFAULT_END
+
 
 BSON_END_DECLS
 

src/libbson/src/bson/bson-iter.h

@@ -95,7 +95,9 @@ static BSON_INLINE uint32_t
 bson_iter_utf8_len_unsafe (const bson_iter_t *iter)
 {
    uint32_t raw;
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    memcpy (&raw, iter->raw + iter->d1, sizeof (raw));
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
 
    const uint32_t native = BSON_UINT32_FROM_LE (raw);
 
@@ -131,7 +133,9 @@ static BSON_INLINE const char *
 bson_iter_code_unsafe (const bson_iter_t *iter, uint32_t *length)
 {
    *length = bson_iter_utf8_len_unsafe (iter);
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    return (const char *) (iter->raw + iter->d2);
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
 }
 
 
@@ -169,7 +173,9 @@ bson_iter_double_unsafe (const bson_iter_t *iter)
 {
    double val;
 
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    memcpy (&val, iter->raw + iter->d1, sizeof (val));
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
    return BSON_DOUBLE_FROM_LE (val);
 }
 
@@ -212,7 +218,9 @@ static BSON_INLINE int32_t
 bson_iter_int32_unsafe (const bson_iter_t *iter)
 {
    uint32_t raw;
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    memcpy (&raw, iter->raw + iter->d1, sizeof (raw));
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
 
    const uint32_t native = BSON_UINT32_FROM_LE (raw);
 
@@ -242,7 +250,9 @@ static BSON_INLINE int64_t
 bson_iter_int64_unsafe (const bson_iter_t *iter)
 {
    uint64_t raw;
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    memcpy (&raw, iter->raw + iter->d1, sizeof (raw));
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
 
    const uint64_t native = BSON_UINT64_FROM_LE (raw);
 
@@ -287,7 +297,9 @@ bson_iter_oid (const bson_iter_t *iter);
 static BSON_INLINE const bson_oid_t *
 bson_iter_oid_unsafe (const bson_iter_t *iter)
 {
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    return (const bson_oid_t *) (iter->raw + iter->d1);
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
 }
 
 
@@ -309,8 +321,10 @@ bson_iter_decimal128_unsafe (const bson_iter_t *iter, bson_decimal128_t *dec)
    uint64_t low_le;
    uint64_t high_le;
 
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    memcpy (&low_le, iter->raw + iter->d1, sizeof (low_le));
    memcpy (&high_le, iter->raw + iter->d1 + 8, sizeof (high_le));
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
 
    dec->low = BSON_UINT64_FROM_LE (low_le);
    dec->high = BSON_UINT64_FROM_LE (high_le);
@@ -335,7 +349,9 @@ bson_iter_key_len (const bson_iter_t *iter);
 static BSON_INLINE const char *
 bson_iter_key_unsafe (const bson_iter_t *iter)
 {
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    return (const char *) (iter->raw + iter->key);
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
 }
 
 
@@ -354,7 +370,9 @@ static BSON_INLINE const char *
 bson_iter_utf8_unsafe (const bson_iter_t *iter, size_t *length)
 {
    *length = bson_iter_utf8_len_unsafe (iter);
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    return (const char *) (iter->raw + iter->d2);
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
 }
 
 
@@ -432,7 +450,9 @@ bson_iter_bool_unsafe (const bson_iter_t *iter)
 {
    char val;
 
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    memcpy (&val, iter->raw + iter->d1, 1);
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
    return !!val;
 }
 
@@ -464,7 +484,9 @@ bson_iter_type (const bson_iter_t *iter);
 static BSON_INLINE bson_type_t
 bson_iter_type_unsafe (const bson_iter_t *iter)
 {
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
    return (bson_type_t) (iter->raw + iter->type)[0];
+   BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
 }
 
 

src/libbson/src/bson/bson-macros.h

@@ -367,4 +367,17 @@
       (void) (expr);      \
    } while (0)
 
+// Disable the -Wunsafe-buffer-usage warning.
+#define BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
+#define BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
+#if defined(__clang__)
+#if __has_warning("-Wunsafe-buffer-usage")
+#undef BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
+#undef BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
+#define BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN \
+   _Pragma ("clang diagnostic push") _Pragma ("clang diagnostic ignored \"-Wunsafe-buffer-usage\"")
+#define BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END _Pragma ("clang diagnostic pop")
+#endif // __has_warning("-Wunsafe-buffer-usage")
+#endif // defined(__clang__)
+
 #endif /* BSON_MACROS_H */

src/libbson/src/bson/bson-oid.h

@@ -114,7 +114,9 @@ bson_oid_hash_unsafe (const bson_oid_t *oid)
    uint32_t i;
 
    for (i = 0; i < sizeof oid->bytes; i++) {
+      BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
       hash = ((hash << 5) + hash) + oid->bytes[i];
+      BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
    }
 
    return hash;
@@ -213,8 +215,10 @@ bson_oid_init_from_string_unsafe (bson_oid_t *oid, const char *str)
    int i;
 
    for (i = 0; i < 12; i++) {
+      BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_BEGIN
       oid->bytes[i] =
          (uint8_t) ((bson_oid_parse_hex_char (str[2 * i]) << 4) | (bson_oid_parse_hex_char (str[2 * i + 1])));
+      BSON_DISABLE_UNSAFE_BUFFER_USAGE_WARNING_END
    }
 }
 

src/libbson/src/bson/bson-types.h

@@ -385,11 +385,10 @@ typedef struct {
  * memory allocations under certain circumstances such as reading from an
  * incoming mongo packet.
  */
-
 BSON_ALIGNED_BEGIN (BSON_ALIGN_OF_PTR)
 typedef struct {
    uint32_t type;
-   /*< private >*/
+   /**< private >**/
 } bson_reader_t BSON_ALIGNED_END (BSON_ALIGN_OF_PTR);