From 097ba5a3592a96b68a5371bbde20c35fc58bd797 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Naz=C4=B1m=20Can=20Bedir?= <jan-dx@zeta.sx>
Date: Mon, 22 Aug 2016 17:26:12 +0300
Subject: [PATCH] Add basic support for Solaris.

---
 include/spdlog/common.h     |  2 ++
 include/spdlog/details/os.h | 45 ++++++++++++++++++++++++++++++++-----
 2 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/include/spdlog/common.h b/include/spdlog/common.h
index 79918a4c..7885292e 100644
--- a/include/spdlog/common.h
+++ b/include/spdlog/common.h
@@ -42,6 +42,8 @@
 #ifndef SPDLOG_ENABLE_SYSLOG
 #if defined (__linux__) || defined(__APPLE__)  || defined(__FreeBSD__)
 #define SPDLOG_ENABLE_SYSLOG
+#elif defined(sun) || defined(__sun)
+#define SPDLOG_ENABLE_SYSLOG
 #endif
 #endif
 
diff --git a/include/spdlog/details/os.h b/include/spdlog/details/os.h
index ccadaea3..a6fbf6d9 100644
--- a/include/spdlog/details/os.h
+++ b/include/spdlog/details/os.h
@@ -198,12 +198,12 @@ inline size_t filesize(FILE *f)
         throw spdlog_ex("Failed getting file size. fd is null");
 #ifdef _WIN32
     int fd = _fileno(f);
-#if _WIN64 //64 bits        
+#if _WIN64 //64 bits
     struct _stat64 st;
     if (_fstat64(fd, &st) == 0)
         return st.st_size;
 
-#else //windows 32 bits     
+#else //windows 32 bits
     struct _stat st;
     if (_fstat(fd, &st) == 0)
         return st.st_size;
@@ -216,7 +216,7 @@ inline size_t filesize(FILE *f)
     struct stat64 st;
     if (fstat64(fd, &st) == 0)
         return st.st_size;
-#else // unix 32 bits or osx    
+#else // unix 32 bits or osx
     struct stat st;
     if (fstat(fd, &st) == 0)
         return st.st_size;
@@ -250,7 +250,42 @@ inline int utc_minutes_offset(const std::tm& tm = details::os::localtime())
         offset -= tzinfo.StandardBias;
     return offset;
 #else
-    return static_cast<int>(tm.tm_gmtoff / 60);
+    long int offset_seconds;
+
+#if defined(sun) || defined(__sun)
+    // 'tm_gmtoff' field is BSD extension and it's missing on SunOS/Solaris
+    struct helper {
+        static long int calculate_gmt_offset(const std::tm & localtm = details::os::localtime(), const std::tm & gmtm = details::os::gmtime()) {
+            int local_year = localtm.tm_year + (1900 - 1);
+            int gmt_year = gmtm.tm_year + (1900 - 1);
+
+            long int days = (
+                // difference in day of year
+                localtm.tm_yday - gmtm.tm_yday
+
+                // + intervening leap days
+                + ((local_year >> 2) - (gmt_year >> 2))
+                - (local_year / 100 - gmt_year / 100)
+                + ((local_year / 100 >> 2) - (gmt_year / 100 >> 2))
+
+                // + difference in years * 365 */
+                + (long int)(local_year - gmt_year) * 365
+            );
+
+            long int hours = (24 * days) + (localtm.tm_hour - gmtm.tm_hour);
+            long int mins = (60 * hours) + (localtm.tm_min - gmtm.tm_min);
+            long int secs = (60 * mins) + (localtm.tm_sec - gmtm.tm_sec);
+
+            return secs;
+        }
+    };
+
+    offset_seconds = helper::calculate_gmt_offset(tm);
+#else
+    offset_seconds = tm.tm_gmtoff;
+#endif
+
+    return static_cast<int>(offset_seconds / 60);
 #endif
 }
 
@@ -269,7 +304,7 @@ inline size_t thread_id()
     long tid;
     thr_self(&tid);
     return static_cast<size_t>(tid);
-#else //Default to standard C++11 (OSX and other Unix)	
+#else //Default to standard C++11 (OSX and other Unix)
     return static_cast<size_t>(std::hash<std::thread::id>()(std::this_thread::get_id()));
 #endif