CRuntime_Musl: More fixes for time64

The original PR (#3275) missed quite a few spots and conversions,
which led to the build on Alpine Linux failing with Aithmetic Exception
on core.time module constructor.
Links to the two offending commits are included.
For further issues / investigation, search for 'time64' in the git repository.

Author: Geod24

src/core/sys/linux/sys/socket.d

@@ -13,6 +13,30 @@ extern(C):
 @nogc:
 nothrow:
 
+version (CRuntime_Musl)
+{
+    import core.stdc.config : c_long;
+    private enum Use_Time64_Values = (time_t.sizeof > c_long.sizeof);
+}
+else
+    private enum Use_Time64_Values = false;
+
+static if (Use_Time64_Values)
+{
+    // SO_TIMESTAMP_OLD & friends
+    // https://www.kernel.org/doc/Documentation/networking/timestamping.txt
+    enum SO_TIMESTAMP = 29;
+    enum SO_TIMESTAMPNS = 35;
+    enum SO_TIMESTAMPING = 37;
+
+}
+else
+{
+    enum SO_TIMESTAMP = 63;
+    enum SO_TIMESTAMPNS = 64;
+    enum SO_TIMESTAMPING = 65;
+}
+
 enum
 {
     // Protocol families.
@@ -123,14 +147,14 @@ enum
     SO_GET_FILTER              = SO_ATTACH_FILTER,
 
     SO_PEERNAME                = 28,
-    SO_TIMESTAMP               = 29,
+    // SO_TIMESTAMP            See above
     SCM_TIMESTAMP              = SO_TIMESTAMP,
 
     SO_PASSSEC                 = 34,
-    SO_TIMESTAMPNS             = 35,
+    // SO_TIMESTAMPNS          See above
     SCM_TIMESTAMPNS            = SO_TIMESTAMPNS,
     SO_MARK                    = 36,
-    SO_TIMESTAMPING            = 37,
+    // SO_TIMESTAMPING         See above
     SCM_TIMESTAMPING           = SO_TIMESTAMPING,
     SO_RXQ_OVFL                = 40,
     SO_WIFI_STATUS             = 41,

src/core/sys/posix/signal.d

@@ -3427,7 +3427,28 @@ struct timespec
 }
 */
 
-version (linux)
+version (CRuntime_Musl)
+{
+    // Musl on 32 bits use 64 bits time_t (time64)
+    // See https://git.musl-libc.org/cgit/musl/commit/?id=9b2921bea1d5017832e1b45d1fd64220047a9802
+    struct timespec
+    {
+        time_t tv_sec;
+        // 32 bits of padding on 32 bits, or in C:
+        // int :8*(sizeof(time_t)-sizeof(long))*(__BYTE_ORDER==4321);
+        version (BigEndian)
+            static if (time_t.sizeof > c_long.sizeof)
+                int __padding;
+        c_long tv_nsec;
+        // Another 32 bits of padding on 32 bits:
+        // int :8*(sizeof(time_t)-sizeof(long))*(__BYTE_ORDER!=4321);
+        version (LittleEndian)
+            static if (time_t.sizeof > c_long.sizeof)
+                int __padding;
+    };
+
+}
+else version (linux)
 {
     struct timespec
     {

src/core/sys/posix/sys/stat.d

@@ -1706,6 +1706,10 @@ else version (CRuntime_Bionic)
 }
 else version (CRuntime_Musl)
 {
+    // version (CRuntime_Musl_Pre_Time64)
+    //     private enum CRuntime_Musl_Use_Old_Layout = 1;
+    // else
+
     alias __mode_t = uint;
     enum {
         S_IRUSR    = 0x100, // octal 0400
@@ -1745,10 +1749,26 @@ else version (CRuntime_Musl)
             blksize_t st_blksize;
             blkcnt_t st_blocks;
 
-            timespec st_atim;
-            timespec st_mtim;
-            timespec st_ctim;
-            ino_t st_ino;
+            // Time64 on 32 bits
+            // See https://git.musl-libc.org/cgit/musl/commit/?id=38143339646a4ccce8afe298c34467767c899f51
+            static if (time_t.sizeof > c_long.sizeof)
+            {
+                private struct old_timespec {
+                    long tv_sec;
+                    long tv_nsec;
+                }
+
+                old_timespec __st_atim32;
+                old_timespec __st_mtim32;
+                old_timespec __st_ctim32;
+            }
+            else // Probably 64 bits or before v1.2.0
+            {
+                timespec st_atim;
+                timespec st_mtim;
+                timespec st_ctim;
+                ino_t st_ino;
+            }
 
             extern(D) @safe @property inout pure nothrow
             {

src/core/sys/posix/sys/types.d

@@ -509,8 +509,10 @@ else version (CRuntime_Musl)
     alias uint id_t;
     version (D_X32)
         alias long susseconds_t;
-    else
+    else version (CRuntime_Musl_Pre_Time64)
         alias c_long suseconds_t;
+    else
+        alias long   suseconds_t;
 }
 else version (CRuntime_UClibc)
 {