Add printf format attribute (#1097)

as suggested by -Wsuggest-attribute=format Handle MinGW and MSVC printf format attributes --------- Co-authored-by: Mike Taves <[email protected]>
libgeos · May 24, 2024 · 93e74e5 · 93e74e5
1 parent 6de25db
commit 93e74e5
Show file tree

Hide file tree

Showing 5 changed files with 46 additions and 6 deletions.
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -307,9 +307,9 @@ target_compile_definitions(geos_developer_cxx_flags
 
 target_compile_options(geos_developer_cxx_flags
   INTERFACE
-    $<$<CXX_COMPILER_ID:MSVC>:-W4>
+    $<$<CXX_COMPILER_ID:MSVC>:-W4>  # consider -analyze
     $<$<OR:$<CXX_COMPILER_ID:GNU>,$<CXX_COMPILER_ID:Clang>,$<CXX_COMPILER_ID:AppleClang>>:-Werror -pedantic -Wall -Wextra -Wno-long-long -Wcast-align -Wconversion -Wsign-conversion -Wchar-subscripts -Wdouble-promotion -Wpointer-arith -Wformat -Wformat-security -Wshadow -Wuninitialized -Wunused-parameter -fno-common>
-    $<$<CXX_COMPILER_ID:GNU>:-fno-implicit-inline-templates -Wno-psabi>
+    $<$<CXX_COMPILER_ID:GNU>:-fno-implicit-inline-templates -Wno-psabi -Wsuggest-attribute=format>
     $<$<OR:$<CXX_COMPILER_ID:Clang>,$<CXX_COMPILER_ID:AppleClang>>:-Wno-unknown-warning-option>
     )
 

diff --git a/capi/geos_c.h.in b/capi/geos_c.h.in
@@ -102,7 +102,8 @@ typedef struct GEOSContextHandle_HS *GEOSContextHandle_t;
 *
 * \param fmt the message format template
 */
-typedef void (*GEOSMessageHandler)(const char *fmt, ...);
+typedef void (*GEOSMessageHandler)(GEOS_PRINTF_FORMAT const char *fmt, ...)
+    GEOS_PRINTF_FORMAT_ATTR(1, 2);
 
 /**
 * A GEOS message handler function.

diff --git a/capi/geos_ts_c.cpp b/capi/geos_ts_c.cpp
@@ -289,15 +289,22 @@ typedef struct GEOSContextHandle_HS {
     }
 
     void
-    NOTICE_MESSAGE(const char *fmt, ...)
+    NOTICE_MESSAGE(GEOS_PRINTF_FORMAT const char *fmt, ...) GEOS_PRINTF_FORMAT_ATTR(2, 3)
     {
         if(nullptr == noticeMessageOld && nullptr == noticeMessageNew) {
             return;
         }
 
         va_list args;
         va_start(args, fmt);
+        #ifdef __MINGW32__
+        #pragma GCC diagnostic push
+        #pragma GCC diagnostic ignored "-Wsuggest-attribute=format"
+        #endif
         int result = vsnprintf(msgBuffer, sizeof(msgBuffer) - 1, fmt, args);
+        #ifdef __MINGW32__
+        #pragma GCC diagnostic pop
+        #endif
         va_end(args);
 
         if(result > 0) {
@@ -311,15 +318,22 @@ typedef struct GEOSContextHandle_HS {
     }
 
     void
-    ERROR_MESSAGE(const char *fmt, ...)
+    ERROR_MESSAGE(GEOS_PRINTF_FORMAT const char *fmt, ...) GEOS_PRINTF_FORMAT_ATTR(2, 3)
     {
         if(nullptr == errorMessageOld && nullptr == errorMessageNew) {
             return;
         }
 
         va_list args;
         va_start(args, fmt);
+        #ifdef __MINGW32__
+        #pragma GCC diagnostic push
+        #pragma GCC diagnostic ignored "-Wsuggest-attribute=format"
+        #endif
         int result = vsnprintf(msgBuffer, sizeof(msgBuffer) - 1, fmt, args);
+        #ifdef __MINGW32__
+        #pragma GCC diagnostic pop
+        #endif
         va_end(args);
 
         if(result > 0) {

diff --git a/include/geos/export.h b/include/geos/export.h
@@ -31,3 +31,21 @@
 #if defined(_MSC_VER)
 #  pragma warning(disable: 4251) // identifier : class type needs to have dll-interface to be used by clients of class type2
 #endif
+
+
+/**********************************************************************
+ * Portability macros
+ **********************************************************************/
+
+#ifdef _MSC_VER
+#include <sal.h>
+#define GEOS_PRINTF_FORMAT _Printf_format_string_
+#define GEOS_PRINTF_FORMAT_ATTR(format_param, dots_param) /**/
+#elif __GNUC__
+#define GEOS_PRINTF_FORMAT /**/
+#define GEOS_PRINTF_FORMAT_ATTR(format_param, dots_param) \
+  __attribute__((format(printf, format_param, dots_param)))
+#else
+#define GEOS_PRINTF_FORMAT /**/
+#define GEOS_PRINTF_FORMAT_ATTR(format_param, dots_param) /**/
+#endif
diff --git a/tests/unit/capi/capi_test_utils.h b/tests/unit/capi/capi_test_utils.h
@@ -61,13 +61,20 @@ namespace capitest {
             finishGEOS();
         }
 
-        static void notice(const char* fmt, ...)
+        static void notice(GEOS_PRINTF_FORMAT const char* fmt, ...) GEOS_PRINTF_FORMAT_ATTR(1, 2)
         {
             std::fprintf(stdout, "NOTICE: ");
 
             va_list ap;
             va_start(ap, fmt);
+            #ifdef __MINGW32__
+            #pragma GCC diagnostic push
+            #pragma GCC diagnostic ignored "-Wsuggest-attribute=format"
+            #endif
             std::vfprintf(stdout, fmt, ap);
+            #ifdef __MINGW32__
+            #pragma GCC diagnostic pop
+            #endif
             va_end(ap);
 
             std::fprintf(stdout, "\n");