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