[vdr] Re: vdr 1.3.19: memory leak in AddDirectory

[Klaus Schmidinger <Klaus.Schmidinger@cadsoft.de>]

Stefan Huelswitt wrote:
> Hi,
> I noticed that there is a memory leak in AddDirectory().
> The functions uses asprint() to malloc the new directory string,
> but on exit this string is strdup'ed by cString and the malloc'ed
> buffer is lost.
>
> The attached patch fixes the problem. If a static sized buffer is
> not acceptable, we would have to use something like:
>
> char buf[strlen(DirName)+strlen(FileName)+3];
>
> But it seems that gcc 2.95.x cannot handle this correctly, at
> least not with -O2.
>
> There is a similiar memory leak in strescape(), but I don't see a
> easy way to resolv this.
I guess what we need here is a way to tell cString to take ownership
of the given string. The attached patch should do this.

Klaus
--- tools.h	2005/01/16 11:39:58	1.65
+++ tools.h	2005/02/05 10:00:22
@@ -61,7 +61,7 @@
 private:
   char *s;
 public:
-  cString(const char *S = NULL);
+  cString(const char *S = NULL, bool TakePointer = false);
   virtual ~cString();
   operator const char * () const { return s; } // for use in (const char *) context
   const char * operator*() const { return s; } // for use in (const void *) context (printf() etc.)
--- tools.c	2005/01/16 11:47:44	1.88
+++ tools.c	2005/02/05 10:10:30
@@ -199,7 +199,7 @@
         }
   if (t)
      *t = 0;
-  return s;
+  return cString(s, t != NULL);
 }
 
 bool startswith(const char *s, const char *p)
@@ -250,7 +250,7 @@
 {
   char *buf;
   asprintf(&buf, "%s/%s", DirName && *DirName ? DirName : ".", FileName);
-  return buf;
+  return cString(buf, true);
 }
 
 cString itoa(int n)
@@ -513,9 +513,9 @@
 
 // --- cString ---------------------------------------------------------------
 
-cString::cString(const char *S)
+cString::cString(const char *S, bool TakePointer)
 {
-  s = S ? strdup(S) : NULL;
+  s = TakePointer ? (char *)S : S ? strdup(S) : NULL;
 }
 
 cString::~cString()