[gimp/gimp-2-10] plug-ins: merge some more warning fixes from master

[Michael Natterer <mitch src gnome org>]

commit bcf6859b01e5a28557ccd619a9aad4fba32be7b1
Author: Michael Natterer <mitch gimp org>
Date:   Sat Jul 6 15:26:33 2019 +0200

    plug-ins: merge some more warning fixes from master

 plug-ins/gradient-flare/gradient-flare.c | 34 +++++++++++++++++++-------------
 1 file changed, 20 insertions(+), 14 deletions(-)
---
diff --git a/plug-ins/gradient-flare/gradient-flare.c b/plug-ins/gradient-flare/gradient-flare.c
index 49cd0978e9..bd6873a4ac 100644
--- a/plug-ins/gradient-flare/gradient-flare.c
+++ b/plug-ins/gradient-flare/gradient-flare.c
@@ -1576,8 +1576,8 @@ static void
 gflare_name_copy (gchar       *dest,
                   const gchar *src)
 {
-  strncpy (dest, src, GFLARE_NAME_MAX);
-  dest[GFLARE_NAME_MAX-1] = '\0';
+  strncpy (dest, src, GFLARE_NAME_MAX - 1);
+  dest[GFLARE_NAME_MAX - 1] = '\0';
 }
 
 /*************************************************************************/
@@ -1915,19 +1915,24 @@ calc_sample_one_gradient (void)
                 {
                   for (j = 0; j < GRADIENT_RESOLUTION; j++)
                     {
-                      gint      r, g, b;
+                      GimpRGB rgb;
+                      GimpHSV hsv;
 
-                      r = gradient[j*4];
-                      g = gradient[j*4+1];
-                      b = gradient[j*4+2];
+                      rgb.r = (gdouble) gradient[j*4]   / 255.0;
+                      rgb.g = (gdouble) gradient[j*4+1] / 255.0;
+                      rgb.b = (gdouble) gradient[j*4+2] / 255.0;
 
-                      gimp_rgb_to_hsv_int (&r, &g, &b);
-                      r = (r + hue) % 256;
-                      gimp_hsv_to_rgb_int (&r, &g, &b);
+                      gimp_rgb_to_hsv (&rgb, &hsv);
 
-                      gradient[j*4] = r;
-                      gradient[j*4+1] = g;
-                      gradient[j*4+2] = b;
+                      hsv.h = (hsv.h + ((gdouble) hue / 255.0));
+                      if (hsv.h > 1.0)
+                        hsv.h -= 1.0;
+
+                      gimp_hsv_to_rgb (&hsv, &rgb);
+
+                      gradient[j*4]   = ROUND (rgb.r * 255.0);
+                      gradient[j*4+1] = ROUND (rgb.g * 255.0);
+                      gradient[j*4+2] = ROUND (rgb.b * 255.0);
                     }
                 }
             }
@@ -4715,8 +4720,8 @@ static void
 gradient_name_copy (gchar       *dest,
                     const gchar *src)
 {
-  strncpy (dest, src, GRADIENT_NAME_MAX);
-  dest[GRADIENT_NAME_MAX-1] = '\0';
+  strncpy (dest, src, GRADIENT_NAME_MAX - 1);
+  dest[GRADIENT_NAME_MAX - 1] = '\0';
 }
 
 /*
@@ -5071,6 +5076,7 @@ gradient_cache_lookup (const gchar *name,
         gradient_cache_zorch();
       ci = g_new (GradientCacheItem, 1);
       strncpy (ci->name, name, GRADIENT_NAME_MAX - 1);
+      ci->name[GRADIENT_NAME_MAX - 1] = '\0';
       ci->next = gradient_cache_head;
       ci->prev = NULL;
       if (gradient_cache_head)