Bug 670788 - When looking for the executable path on Unix, only use realpath() when we got a file path in the first place. r=bsmedberg

xpcom/build/BinaryPath.h

@@ -46,6 +46,7 @@
 #include <CoreFoundation/CoreFoundation.h>
 #elif defined(XP_UNIX)
 #include <sys/stat.h>
+#include <string.h>
 #endif
 
 namespace mozilla {
@@ -102,10 +103,11 @@ private:
     // multiple applications, we will try a series of techniques:
     //
     // 1) use realpath() on argv[0], which works unless we're loaded from the
-    //    PATH
+    //    PATH. Only do so if argv[0] looks like a path (contains a /).
     // 2) manually walk through the PATH and look for ourself
     // 3) give up
-    if (realpath(argv0, aResult) && stat(aResult, &fileStat) == 0)
+    if (strchr(argv0, '/') && realpath(argv0, aResult) &&
+        stat(aResult, &fileStat) == 0)
       return NS_OK;
 
     const char *path = getenv("PATH");