Add better checking and error messages.

stepmania/PBProject/Installer/Processor.cpp

@@ -43,6 +43,9 @@ mError(Processor::DefaultError), mInstalling(i)
 
     if (mInstalling)
     {
+        if (!DoesFileExist(path))
+            throw CString("Archive file not present.");
+        
         char archivePath[] = "/tmp/installerXXXXXX.tar";
         int fd = mkstemps(archivePath, 4);
 
@@ -53,11 +56,15 @@ mError(Processor::DefaultError), mInstalling(i)
 
         char toolPath[] = "/usr/bin/gunzip";
         
+        try {
             if(CallTool2(true, -1, fd, -1, toolPath, "-c", path.c_str(), NULL))
-        {
+                throw CString("Archive file not handled correctly.");
+        } catch (CString& e) {
+            close(fd);
             unlink(mPath);
-            throw CString("Archive file not handled correctly or not present.");
+            throw;
         }
+        close(fd);
     }
     else
         mPath = path;

stepmania/PBProject/Installer/Util.cpp

@@ -119,6 +119,8 @@ err:
 
 int CallTool3(bool blocking, int fd_in, int fd_out, int fd_err, const char *path, char *const *arguments)
 {
+    if (!DoesFileExist(path))
+        throw CString("The tool \"") + path + "\" does not exist.";
     pid_t pid = fork();
 
     switch (pid)