commit 5b4e97ce59a60ba7606529df3cd9a068b7bbf7ba
author Pali Rohár <pali.rohar@gmail.com> Sun Jul 13 12:56:21 2025 +0200
committer Martin Storsjö <martin@martin.st> Fri Aug 01 20:15:43 2025 +0300
tree a9417ae917bcf597df6e71d6c4a3d64656761779
parent 79ed1bcf1e6d4a5b62db94a1c99dd6f57d379a8c

crt: Add emulation of _get_tzname() function for pre-msvcr80 import libs

Function _get_tzname() is available in msvcr80+ and UCRT.

Signed-off-by: Martin Storsjö <martin@martin.st>

mingw-w64-crt/Makefile.am

diff --git a/mingw-w64-crt/Makefile.am b/mingw-w64-crt/Makefile.am
index 23962a6..fa08d16 100644
--- a/mingw-w64-crt/Makefile.am
+++ b/mingw-w64-crt/Makefile.am
@@ -335,6 +335,7 @@
   misc/_get_daylight.c \
   misc/_get_dstbias.c \
   misc/_get_timezone.c \
+  misc/_get_tzname.c \
   misc/_recalloc.c \
   misc/_set_purecall_handler.c \
   misc/imaxdiv.c \
@@ -884,6 +885,7 @@
   misc/_get_dstbias.c \
   misc/_get_errno.c \
   misc/_get_timezone.c \
+  misc/_get_tzname.c \
   misc/_initterm_e.c \
   misc/_recalloc.c \
   misc/_set_errno.c \

mingw-w64-crt/misc/_get_tzname.c

diff --git a/mingw-w64-crt/misc/_get_tzname.c b/mingw-w64-crt/misc/_get_tzname.c
new file mode 100644
index 0000000..b5a9186
--- /dev/null
+++ b/mingw-w64-crt/misc/_get_tzname.c
@@ -0,0 +1,42 @@
+/**
+ * This file has no copyright assigned and is placed in the Public Domain.
+ * This file is part of the mingw-w64 runtime package.
+ * No warranty is given; refer to the file DISCLAIMER.PD within this package.
+ */
+#include <time.h>
+#include <errno.h>
+#include <string.h>
+
+errno_t __cdecl _get_tzname(size_t *length, char *buffer, size_t size, int index)
+{
+  const char *tzname_ptr;
+
+  if ((!buffer && size != 0) || (buffer && size == 0))
+  {
+    errno = EINVAL;
+    return EINVAL;
+  }
+
+  if (buffer)
+    buffer[0] = '\0';
+
+  if (!length || (index != 0 && index != 1))
+  {
+    errno = EINVAL;
+    return EINVAL;
+  }
+
+  tzname_ptr = _tzname[index];
+
+  *length = strlen(tzname_ptr) + 1;
+
+  if (buffer)
+  {
+    if (*length > size)
+      return ERANGE;
+    memcpy(buffer, tzname_ptr, *length);
+  }
+
+  return 0;
+}
+errno_t (__cdecl *__MINGW_IMP_SYMBOL(_get_tzname))(size_t *, char *, size_t, int) = _get_tzname;