resolve.s

来自「它通过提供glibc兼容使得应用程序移植到较小的c 库时相当得容易. 它能够应用」· S 代码 · 共 49 行

/*
 * This function is _not_ called directly.  It is jumped to from PLT 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.  When we get called 
 * the stack contains reloc_offset and tpnt is in MOF.
 *
 * We save all the registers, setup R10 and R11 with the right arguments 
 * then call _dl_linux_resolver(tpnt, reloc_offset). _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.
 */		  

.globl _dl_linux_resolve
.type _dl_linux_resolve,@function

_dl_linux_resolve:
	push $r13
	push $r12
	push $r11
	push $r10
	push $r9
	push $srp
	move.d [$sp+6*4],$r11
	move $mof,$r10
#ifdef __PIC__
	move.d $pc,$r0
	sub.d .:GOTOFF,$r0
	move.d _dl_linux_resolver:PLTG,$r9
	add.d $r0,$r9
	jsr $r9
#else
	jsr _dl_linux_resolver
#endif
	move.d $r10,[$sp+6*4]
	pop $srp
	pop $r9
	pop $r10
	pop $r11
	pop $r12
	pop $r13
	jump [$sp+]

	.size _dl_linux_resolve, . - _dl_linux_resolve