Returning false if file does not end with .class #580
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When using scriptOutputDir as a param to -javaagent, the folder might contain non Java class files. Ensuring that the files loaded into BTrace is a .class file.
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| private static boolean loadBTraceScript(String filePath, boolean traceToStdOut) { | ||
| if (!filePath.endsWith(".class")) { |
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Could you modify this to look at the magic bytes instead?
For Java class files it would be 0xCAFEBABE and for the BTrace probe-pack it is 0xBACECACA.
The problem with only extension check is that the BTrace probe-pack can have any extension name - it is not really standardized. For simplicity it defaults to .class but it is possible to specify some other extension so you eg. don't confuse the classloader if the BTrace probe pack files are put together with regular class files.
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How would I check for the magic bytes? Is it as simple as opening the file, read the first few bytes and compare them to the mentioned 2 magic bytes?
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Oh, I am sorry, I completely missed the notification about the activity here :(
Yes, it is exactly the way you are describing. It is 4 first bytes of the file which is containing the magic number.
jbachorik
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jbachorik
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Hi, thanks for contributing!
Please, see my comments 'inline'
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Hi @joachimhs , same as for #579 - will you be able to finish this PR, please? |
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Ok, I am going to merge as it is and add the magic number checks as a followup step. |
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When using scriptOutputDir as a param to -javaagent, the folder might contain non Java class files. Ensuring that the files loaded into BTrace is a .class file.