Macro which checks the opening of a root file and detects some problems like truncation

diff --git a/macros/checkFile.C b/macros/checkFile.C
new file mode 100644 (file)
index 0000000..bc3de1a
--- /dev/null
+++ b/macros/checkFile.C
@@ -0,0 +1,54 @@
+#if !defined( __CINT__) || defined(__MAKECINT__)
+#include <stdio.h>
+#include <unistd.h>
+#include <TString.h>
+#include <TSystem.h>
+#include <TROOT.h>
+#include <TFile.h>
+#endif
+
+Bool_t checkFile(const char* filename)
+{
+  // This macro returns FALSE in the following cases:
+  // - the file doesn't exist
+  // - the file is not readable
+  // - the file is not a Root file
+  // - the file is truncated
+  // If the file is opened without any Error message,
+  // the macro returns kTRUE
+
+  // checkname is string with appended .check, i.e. Kinematics.root.check
+  // The output of TFile::Open will be stored there
+  TString checkname = filename;
+  checkname += ".check";
+
+  // remove checkname, if it already exists
+  gSystem->Unlink(checkname.Data());
+
+  // Copy and store the original stream desriptors
+  Int_t origstdout = dup(fileno(stdout));
+  Int_t origstderr = dup(fileno(stderr));
+
+  // Redirect the output
+  freopen(checkname.Data(),"w",stdout);
+  dup2(fileno(stdout),fileno(stderr));
+
+  // Try to open the file. The output goes to the file checkname
+  TFile f(filename);
+
+  // Restore the original stream descriptors
+  dup2(origstdout,fileno(stdout));
+  dup2(origstderr,fileno(stderr));
+
+  // Prepare the grep command, executed by the shell, for example
+  // grep Error Kinematics.root.check > /dev/null 2>&1
+  TString command = "grep Error ";
+  command += checkname;
+  command += " > /dev/null 2>&1";
+  // Execute the command. The return value is 0 if Error is found
+  Bool_t result = gSystem->Exec(command.Data());
+
+  // Remove the checkname
+  gSystem->Unlink(checkname.Data());
+  return result;
+}