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phoenix |
/*
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* This function is _not_ called directly. It is jumped to (so no return
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* address is on the stack) when attempting to use a symbol that has not yet
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* been resolved. The first time a jump symbol (such as a function call inside
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* a shared library) is used (before it gets resolved) it will jump here to
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* _dl_linux_resolve. When we get called the stack looks like this:
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* reloc_entry
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* tpnt
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*
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* This function saves all the registers, puts a copy of reloc_entry and tpnt
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* on the stack (as function arguments) then make the function call
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* _dl_linux_resolver(tpnt, reloc_entry). _dl_linux_resolver() figures out
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* where the jump symbol is _really_ supposed to have jumped to and returns
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* that to us. Once we have that, we overwrite tpnt with this fixed up
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* address. We then clean up after ourselves, put all the registers back how we
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* found them, then we jump to where the fixed up address, which is where the
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* jump symbol that got us here really wanted to jump to in the first place.
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* found them, then we jump to the fixed up address, which is where the jump
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* symbol that got us here really wanted to jump to in the first place.
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* -Erik Andersen
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*/
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.text
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.align 4
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.globl _dl_linux_resolve
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.type _dl_linux_resolve,@function
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_dl_linux_resolve:
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pusha /* preserve all regs */
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lea 0x20(%esp),%eax /* eax = tpnt and reloc_entry params */
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pushl 4(%eax) /* push copy of reloc_entry param */
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pushl (%eax) /* push copy of tpnt param */
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#ifdef __PIC__
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call .L24
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.L24:
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popl %ebx
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addl $_GLOBAL_OFFSET_TABLE_+[.-.L24],%ebx
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movl _dl_linux_resolver@GOT(%ebx),%ebx /* eax = resolved func */
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call *%ebx
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#else
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call _dl_linux_resolver
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#endif
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movl %eax,0x28(%esp) /* store func addr over original
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* tpnt param */
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addl $0x8,%esp /* remove copy parameters */
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popa /* restore regs */
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ret $4 /* jump to func removing original
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* reloc_entry param from stack */
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.LFE2:
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.size _dl_linux_resolve,.LFE2-_dl_linux_resolve
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