strcat+strcat+strcat == baaad

[Francois Gouget <fgouget@free.fr>]

I don't like pieces of code that go:

  strcpy(foo, bar1);
  strcat(foo, bar2);
  strcat(foo, bar3);
  strcat(foo, bar4);
  strcat(foo, bar5);
  strcat(foo, bar6);

It's really inefficient: the cost increases quadratically with the size
of the resulting string. It's more efficient to do:

  sprintf(foo, "%s%s%s%s%s%s", bar1,bar2,bar3,bar4,bar5,bar6);

Here the cost is proportional to the size of the resulting string.

For for various reasons I came accross a couple of instances of
strcat+strcat badness and replaced them with a sprintf. So here's the
patch.

Changelog:

 * memory/environ.c,
   tools/makedep.c

   Use sprintf rather than calling strcat over and over


Index: memory/environ.c
===================================================================
RCS file: /home/wine/wine/memory/environ.c,v
retrieving revision 1.38
diff -u -r1.38 environ.c
--- memory/environ.c	9 Oct 2002 18:35:02 -0000	1.38
+++ memory/environ.c	30 Nov 2002 05:20:12 -0000
@@ -641,12 +641,7 @@

     /* Set the new string */

-    if (value)
-    {
-        strcpy( p, name );
-        strcat( p, "=" );
-        strcat( p, value );
-    }
+    if (value) sprintf( p, "%s=%s", name, value );
     current_envdb.env = new_env;
     ret = TRUE;

Index: tools/makedep.c
===================================================================
RCS file: /home/wine/wine/tools/makedep.c,v
retrieving revision 1.13
diff -u -r1.13 makedep.c
--- tools/makedep.c	17 Aug 2002 18:28:43 -0000	1.13
+++ tools/makedep.c	30 Nov 2002 06:10:17 -0000
@@ -192,9 +192,7 @@
     if (SrcDir)
     {
         pFile->filename = xmalloc( strlen(SrcDir) + strlen(pFile->name) + 2 );
-        strcpy( pFile->filename, SrcDir );
-        strcat( pFile->filename, "/" );
-        strcat( pFile->filename, pFile->name );
+        sprintf( pFile->filename, "%s/%s", SrcDir, pFile->name );
     }
     else pFile->filename = xstrdup( pFile->name );

@@ -218,9 +216,7 @@
     for (path = firstPath; path; path = path->next)
     {
         char *filename = xmalloc(strlen(path->name) + strlen(pFile->name) + 2);
-        strcpy( filename, path->name );
-        strcat( filename, "/" );
-        strcat( filename, pFile->name );
+        sprintf( filename, "%s/%s", path->name, pFile->name );
         if ((file = fopen( filename, "r" )))
         {
             pFile->filename = filename;


-- 
Francois Gouget         fgouget@free.fr        http://fgouget.free.fr/
                Linux: It is now safe to turn on your computer.