diff --git a/include/freetype/config/ftstdlib.h b/include/freetype/config/ftstdlib.h
index 3c9d2ae..f65148a 100644
--- a/include/freetype/config/ftstdlib.h
+++ b/include/freetype/config/ftstdlib.h
@@ -111,13 +111,13 @@
 
 #include <stdio.h>
 
-#define FT_FILE     FILE
-#define ft_fclose   fclose
-#define ft_fopen    fopen
-#define ft_fread    fread
-#define ft_fseek    fseek
-#define ft_ftell    ftell
-#define ft_sprintf  sprintf
+#define FT_FILE      FILE
+#define ft_fclose    fclose
+#define ft_fopen     fopen
+#define ft_fread     fread
+#define ft_fseek     fseek
+#define ft_ftell     ftell
+#define ft_snprintf  snprintf
 
 
   /**************************************************************************
diff --git a/src/autofit/afhints.c b/src/autofit/afhints.c
index 6515af9..e4a378f 100644
--- a/src/autofit/afhints.c
+++ b/src/autofit/afhints.c
@@ -320,8 +320,9 @@
 
 
   static char*
-  af_print_idx( char* p,
-                int   idx )
+  af_print_idx( char*   p,
+                size_t  n,
+                int     idx )
   {
     if ( idx == -1 )
     {
@@ -330,7 +331,7 @@
       p[2] = '\0';
     }
     else
-      ft_sprintf( p, "%d", idx );
+      ft_snprintf( p, n, "%d", idx );
 
     return p;
   }
@@ -457,12 +458,12 @@
                 " %5d %5d %7.2f %7.2f %7.2f %7.2f"
                 " %5s %5s %5s %5s\n",
                 point_idx,
-                af_print_idx( buf1,
+                af_print_idx( buf1, 16,
                               af_get_edge_index( hints, segment_idx_1, 1 ) ),
-                af_print_idx( buf2, segment_idx_1 ),
-                af_print_idx( buf3,
+                af_print_idx( buf2, 16, segment_idx_1 ),
+                af_print_idx( buf3, 16,
                               af_get_edge_index( hints, segment_idx_0, 0 ) ),
-                af_print_idx( buf4, segment_idx_0 ),
+                af_print_idx( buf4, 16, segment_idx_0 ),
                 ( point->flags & AF_FLAG_NEAR )
                   ? " near "
                   : ( point->flags & AF_FLAG_WEAK_INTERPOLATION )
@@ -476,18 +477,22 @@
                 (double)point->x / 64,
                 (double)point->y / 64,
 
-                af_print_idx( buf5, af_get_strong_edge_index( hints,
-                                                              point->before,
-                                                              1 ) ),
-                af_print_idx( buf6, af_get_strong_edge_index( hints,
-                                                              point->after,
-                                                              1 ) ),
-                af_print_idx( buf7, af_get_strong_edge_index( hints,
-                                                              point->before,
-                                                              0 ) ),
-                af_print_idx( buf8, af_get_strong_edge_index( hints,
-                                                              point->after,
-                                                              0 ) ) ));
+                af_print_idx( buf5, 16,
+                              af_get_strong_edge_index( hints,
+                                                        point->before,
+                                                        1 ) ),
+                af_print_idx( buf6, 16,
+                              af_get_strong_edge_index( hints,
+                                                        point->after,
+                                                        1 ) ),
+                af_print_idx( buf7, 16,
+                              af_get_strong_edge_index( hints,
+                                                        point->before,
+                                                        0 ) ),
+                af_print_idx( buf8, 16,
+                              af_get_strong_edge_index( hints,
+                                                        point->after,
+                                                        0 ) ) ));
     }
     AF_DUMP(( "\n" ));
   }
@@ -574,9 +579,12 @@
                   AF_INDEX_NUM( seg->first, points ),
                   AF_INDEX_NUM( seg->last, points ),
 
-                  af_print_idx( buf1, AF_INDEX_NUM( seg->link, segments ) ),
-                  af_print_idx( buf2, AF_INDEX_NUM( seg->serif, segments ) ),
-                  af_print_idx( buf3, AF_INDEX_NUM( seg->edge, edges ) ),
+                  af_print_idx( buf1, 16,
+                                AF_INDEX_NUM( seg->link, segments ) ),
+                  af_print_idx( buf2, 16,
+                                AF_INDEX_NUM( seg->serif, segments ) ),
+                  af_print_idx( buf3, 16,
+                                AF_INDEX_NUM( seg->edge, edges ) ),
 
                   seg->height,
                   seg->height - ( seg->max_coord - seg->min_coord ),
@@ -716,8 +724,10 @@
                   AF_INDEX_NUM( edge, edges ),
                   (double)(int)edge->opos / 64,
                   af_dir_str( (AF_Direction)edge->dir ),
-                  af_print_idx( buf1, AF_INDEX_NUM( edge->link, edges ) ),
-                  af_print_idx( buf2, AF_INDEX_NUM( edge->serif, edges ) ),
+                  af_print_idx( buf1, 16,
+                                AF_INDEX_NUM( edge->link, edges ) ),
+                  af_print_idx( buf2, 16,
+                                AF_INDEX_NUM( edge->serif, edges ) ),
 
                   edge->blue_edge ? 'y' : 'n',
                   (double)edge->opos / 64,
diff --git a/src/bdf/bdflib.c b/src/bdf/bdflib.c
index 936829b..0fa7e0a 100644
--- a/src/bdf/bdflib.c
+++ b/src/bdf/bdflib.c
@@ -51,6 +51,9 @@
 #define FT_COMPONENT  bdflib
 
 
+#define BUFSIZE  128
+
+
   /**************************************************************************
    *
    * Default BDF font options.
@@ -1773,7 +1776,7 @@
     bdf_parse_t_*      p;
     char*              name;
     char*              value;
-    char               nbuf[128];
+    char               nbuf[BUFSIZE];
     FT_Error           error = FT_Err_Ok;
 
     FT_UNUSED( lineno );
@@ -1794,7 +1797,7 @@
       if ( bdf_get_font_property( p->font, "FONT_ASCENT" ) == 0 )
       {
         p->font->font_ascent = p->font->bbx.ascent;
-        ft_sprintf( nbuf, "%hd", p->font->bbx.ascent );
+        ft_snprintf( nbuf, BUFSIZE, "%hd", p->font->bbx.ascent );
         error = bdf_add_property_( p->font, "FONT_ASCENT",
                                    nbuf, lineno );
         if ( error )
@@ -1806,7 +1809,7 @@
       if ( bdf_get_font_property( p->font, "FONT_DESCENT" ) == 0 )
       {
         p->font->font_descent = p->font->bbx.descent;
-        ft_sprintf( nbuf, "%hd", p->font->bbx.descent );
+        ft_snprintf( nbuf, BUFSIZE, "%hd", p->font->bbx.descent );
         error = bdf_add_property_( p->font, "FONT_DESCENT",
                                    nbuf, lineno );
         if ( error )
@@ -2114,7 +2117,7 @@
     /* Check for the CHARS field -- font properties are optional */
     if ( _bdf_strncmp( line, "CHARS", 5 ) == 0 )
     {
-      char  nbuf[128];
+      char  nbuf[BUFSIZE];
 
 
       if ( !( p->flags & BDF_FONT_BBX_ ) )
@@ -2128,7 +2131,7 @@
       /* Add the two standard X11 properties which are required */
       /* for compiling fonts.                                   */
       p->font->font_ascent = p->font->bbx.ascent;
-      ft_sprintf( nbuf, "%hd", p->font->bbx.ascent );
+      ft_snprintf( nbuf, BUFSIZE, "%hd", p->font->bbx.ascent );
       error = bdf_add_property_( p->font, "FONT_ASCENT",
                                  nbuf, lineno );
       if ( error )
@@ -2136,7 +2139,7 @@
       FT_TRACE2(( "bdf_parse_properties_: " ACMSG1, p->font->bbx.ascent ));
 
       p->font->font_descent = p->font->bbx.descent;
-      ft_sprintf( nbuf, "%hd", p->font->bbx.descent );
+      ft_snprintf( nbuf, BUFSIZE, "%hd", p->font->bbx.descent );
       error = bdf_add_property_( p->font, "FONT_DESCENT",
                                  nbuf, lineno );
       if ( error )
diff --git a/src/tools/ftrandom/ftrandom.c b/src/tools/ftrandom/ftrandom.c
index 4f912cd..0ee765e 100644
--- a/src/tools/ftrandom/ftrandom.c
+++ b/src/tools/ftrandom/ftrandom.c
@@ -520,7 +520,7 @@
     char        buffer[1024];
 
 
-    sprintf( buffer, "%s/test%d", results_dir, test_num++ );
+    snprintf( buffer, 1024, "%s/test%d", results_dir, test_num++ );
 
     if ( copyfont ( &fontlist[i], buffer ) )
     {