Fix checks for gmtime_r and localtime_r availability.

Actually check for the functions in configure.ac and CMakeLists.txt,
which is the only way of definitively testing for them, since feature
test macros such as _POSIX_C_SOURCE are supposed to be used to tell
system headers what functions should be exposed, and the application
shouldn't check their values.

Add a warning for cases where gmtime() or localtime() are used.

Also fix Http_Cookies where gmtime() was still being used.

4 files changed, 38 insertions, 3 deletions

diff --git a/Project/CMake/CMakeLists.txt b/Project/CMake/CMakeLists.txt
index 8e431b5..6a25aee 100644
--- a/Project/CMake/CMakeLists.txt
+++ b/Project/CMake/CMakeLists.txt
@@ -133,6 +133,16 @@ if((LONG_SIZE GREATER 4) AND (SIZE_T_SIZE EQUAL LONG_SIZE))
   target_compile_definitions(zen PUBLIC SIZE_T_IS_LONG)

 endif()

 

+include(CheckSymbolExists)

+check_symbol_exists(gmtime_r time.h HAVE_GMTIME_R)

+if(HAVE_GMTIME_R)

+  target_compile_definitions(zen PUBLIC HAVE_GMTIME_R)

+endif()

+check_symbol_exists(localtime_r time.h HAVE_LOCALTIME_R)

+if(HAVE_LOCALTIME_R)

+  target_compile_definitions(zen PUBLIC HAVE_LOCALTIME_R)

+endif()

+

 target_include_directories(zen PUBLIC

   $<BUILD_INTERFACE:${ZenLib_SOURCES_PATH}>

   $<INSTALL_INTERFACE:${INCLUDE_INSTALL_DIR}>)

diff --git a/Project/GNU/Library/configure.ac b/Project/GNU/Library/configure.ac
index 1d8bb3e..cbed25b 100644
--- a/Project/GNU/Library/configure.ac
+++ b/Project/GNU/Library/configure.ac
@@ -254,6 +254,11 @@ dnl External libs
 dnl
 LDFLAGS="$LDFLAGS -lpthread"
 
+dnl -------------------------------------------------------------------------
+dnl Check if thread safe variants of time functions are available
+dnl
+AC_CHECK_FUNCS(gmtime_r localtime_r)
+
 dnl #########################################################################
 dnl ### Output
 dnl #########################################################################
diff --git a/Source/ZenLib/Format/Http/Http_Cookies.cpp b/Source/ZenLib/Format/Http/Http_Cookies.cpp
index 1345aa0..eb41690 100644
--- a/Source/ZenLib/Format/Http/Http_Cookies.cpp
+++ b/Source/ZenLib/Format/Http/Http_Cookies.cpp
@@ -86,7 +86,21 @@ void Cookies::Create_Lines(std::ostream& Out)
         if (Cookie->second.Expires!=(time_t)-1)

         {

             char Temp[200];

-            if (strftime(Temp, 200, "%a, %d-%b-%Y %H:%M:%S GMT", gmtime(&Cookie->second.Expires)))

+            #if defined(HAVE_GMTIME_R)

+            struct tm Gmt_Temp;

+            struct tm *Gmt=gmtime_r(&Cookie->second.Expires, &Gmt_Temp);

+            #elif defined(_MSC_VER)

+            struct tm Gmt_Temp;

+            errno_t gmtime_s_Result=gmtime_s(&Gmt_Temp , &Cookie->second.Expires);

+            struct tm* Gmt=gmtime_s_Result?NULL:&Gmt_Temp;

+            #else

+            #ifdef __GNUC__

+            #warning "This version of ZenLib is not thread safe"

+            #endif

+            struct tm *Gmt=gmtime(&Cookie->second.Expires);

+            #endif

+

+            if (strftime(Temp, 200, "%a, %d-%b-%Y %H:%M:%S GMT", Gmt))

                 Out << "; expires=" << Temp;

         }

         if (!Cookie->second.Path.empty())

diff --git a/Source/ZenLib/Ztring.cpp b/Source/ZenLib/Ztring.cpp
index 21bbc58..31525b5 100644
--- a/Source/ZenLib/Ztring.cpp
+++ b/Source/ZenLib/Ztring.cpp
@@ -1312,7 +1312,7 @@ Ztring& Ztring::Date_From_Seconds_1970 (const int32s Value)
 Ztring& Ztring::Date_From_Seconds_1970 (const int64s Value)

 {

     time_t Time=(time_t)Value;

-    #if _POSIX_C_SOURCE >= 1 || _XOPEN_SOURCE || _BSD_SOURCE || _SVID_SOURCE || _POSIX_SOURCE

+    #if defined(HAVE_GMTIME_R)

     struct tm Gmt_Temp;

     struct tm *Gmt=gmtime_r(&Time, &Gmt_Temp);

     #elif defined(_MSC_VER)

@@ -1320,6 +1320,9 @@ Ztring& Ztring::Date_From_Seconds_1970 (const int64s Value)
     errno_t gmtime_s_Result=gmtime_s(&Gmt_Temp , &Time);

     struct tm* Gmt=gmtime_s_Result?NULL:&Gmt_Temp;

     #else

+    #ifdef __GNUC__

+    #warning "This version of ZenLib is not thread safe"

+    #endif

     struct tm *Gmt=gmtime(&Time);

     #endif

     if (!Gmt)

@@ -1352,7 +1355,7 @@ Ztring& Ztring::Date_From_Seconds_1970 (const int64s Value)
 Ztring& Ztring::Date_From_Seconds_1970_Local (const int32u Value)

 {

     time_t Time=(time_t)Value;

-    #if _POSIX_C_SOURCE >= 1 || _XOPEN_SOURCE || _BSD_SOURCE || _SVID_SOURCE || _POSIX_SOURCE

+    #if defined(HAVE_LOCALTIME_R)

     struct tm Gmt_Temp;

     struct tm *Gmt=localtime_r(&Time, &Gmt_Temp);

     #elif defined(_MSC_VER)

@@ -1360,6 +1363,9 @@ Ztring& Ztring::Date_From_Seconds_1970_Local (const int32u Value)
     errno_t localtime_s_Result=localtime_s(&Gmt_Temp , &Time);

     struct tm* Gmt=localtime_s_Result?NULL:&Gmt_Temp;

     #else

+    #ifdef __GNUC__

+    #warning "This version of ZenLib is not thread safe"

+    #endif

     struct tm *Gmt=localtime(&Time);

     #endif

     Ztring DateT;