[babl] tools: use _putenv_s() instead of setenv() on Windows.

[Jehan <jehanp src gnome org>]

commit 8769953c4c0342f1250db01a1570cd69b71c9c71
Author: Jehan <jehan girinstud io>
Date:   Thu Jan 27 17:39:49 2022 +0100

    tools: use _putenv_s() instead of setenv() on Windows.
    
    setenv() does not exist on Windows API, hence babl tools fail to build.
    Fixing the issue by using an alternative Windows API.

 tools/babl-benchmark.c  | 7 +++++++
 tools/babl-lut-verify.c | 7 +++++++
 tools/babl-verify.c     | 7 +++++++
 3 files changed, 21 insertions(+)
---
diff --git a/tools/babl-benchmark.c b/tools/babl-benchmark.c
index d12dbb59e..32d66c2d2 100644
--- a/tools/babl-benchmark.c
+++ b/tools/babl-benchmark.c
@@ -25,6 +25,13 @@
 #define random  rand
 #endif
 
+#ifdef _WIN32
+/* On Windows setenv() does not exist, using _putenv_s() instead. The overwrite
+ * arg is ignored (i.e. same as always 1).
+ */
+#define setenv(name,value,overwrite) _putenv_s(name, value)
+#endif
+
 int ITERATIONS = 4;
 #define  N_PIXELS (1024*1024)  // a too small batch makes the test set live
                                // in l2 cache skewing results
diff --git a/tools/babl-lut-verify.c b/tools/babl-lut-verify.c
index 25a8abc40..c857edd9d 100644
--- a/tools/babl-lut-verify.c
+++ b/tools/babl-lut-verify.c
@@ -10,6 +10,13 @@
 #define random rand
 #endif
 
+#ifdef _WIN32
+/* On Windows setenv() does not exist, using _putenv_s() instead. The overwrite
+ * arg is ignored (i.e. same as always 1).
+ */
+#define setenv(name,value,overwrite) _putenv_s(name, value)
+#endif
+
 static double
 test_generic (const Babl *source, const Babl *dest)
 {
diff --git a/tools/babl-verify.c b/tools/babl-verify.c
index 75aaa9ccf..b76f707c8 100644
--- a/tools/babl-verify.c
+++ b/tools/babl-verify.c
@@ -8,6 +8,13 @@
 #define SPACE1 babl_space("sRGB")
 //#define SPACE2 babl_space("Apple")
 
+#ifdef _WIN32
+/* On Windows setenv() does not exist, using _putenv_s() instead. The overwrite
+ * arg is ignored (i.e. same as always 1).
+ */
+#define setenv(name,value,overwrite) _putenv_s(name, value)
+#endif
+
 int
 file_get_contents (const char  *path,
                          char       **contents,