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Hello, |
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I have noticed something strange in the handling of tcpwrapper's |
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global variables "allow_severity" and "deny_severity". |
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I'm using gcc 2.95.3. |
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The tcp_wrappers library requires the main program to define |
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those symbols. The ntop package, for example, declares the variables in |
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an include file, and never initializes them. |
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I have changed the code to conditionally initialize the variables |
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and it compiles fine. (this should fix bug #4678). |
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However I would like to look deeply in the problem. |
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I don't understand why those symbols are required to be initialized. |
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Declared symbols should be marked as "C" (common) on compilation |
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and promoted to "B" (bss uninitialized). I tried with test programs |
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and also linking libwrap.a, the variables are marked "B" by nm. |
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The only reference to allow_severity in ntop is in "globals.h" file |
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and is *not* marked as extern. In tcp_wrappers is marked as extern. |
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I cannot regenerate the problem with a simpler program, it |
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always correctly resolves the non extern multiple declaration |
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in bss unitialized symbol. |
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Does anyone know why is this happening, and why this |
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thing does obviously not happen to the ntop and mysql developers ? |
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Marko |
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