User:Nicolas17/MobileMail/MessageViewController/previewActionForSwipeAction:withMessage:forSwipe:: Difference between revisions
From iPhone Development Wiki
< User:Nicolas17 | MobileMail
(→Decompiled code: Add assembly for the jumptable stuff I'm missing) |
(Clarify conditionals involving x8) |
||
Line 31: | Line 31: | ||
w28 = 0xc2000000 // from "movz w28, #0xc200, lsl #16"; I don't know if that's correct | w28 = 0xc2000000 // from "movz w28, #0xc200, lsl #16"; I don't know if that's correct | ||
x8 = x19 - 5 // _shiftedAction = action - 5 | x8 = x19 - 5 // _shiftedAction = action - 5 | ||
if (x8 > 0) goto L1; | if (x8 > 0) goto L1; // if (action > 5) | ||
/* TODO; involves jumptable | /* TODO; involves jumptable | ||
Line 43: | Line 43: | ||
L1: // 0x10009bd4c | L1: // 0x10009bd4c | ||
if (x8 > 1) goto L2; | if (x8 > 1) goto L2; // if (action > 6) | ||
// TODO | // TODO |
Revision as of 22:54, 14 February 2016
This method is actually called
-[MessageViewController _previewActionForSwipeAction:withMessage:forSwipe]
, but underscores cannot be used in wiki page names.-(UIPreviewAction*)_previewActionForSwipeAction:(unsigned long long)action withMessage:(id)message forSwipe:(BOOL)swipe;
This method in MessageViewController
creates a UIPreviewAction object (action shown in the 3D Touch "peek" view).
It's called by leadingPreviewAction
and trailingPreviewAction
to get the actions on the sides of the peek, and by _previewActionsForSwipeActions:excludingSwipeActions:
for the actions at the bottom.
Reverse engineering info
I'm starting to decompile this method and will put the pseudocode in this page.
This method contains two jump tables (at least in arm64), presumably compiled from switch statements, which Hopper doesn't handle automatically even in the disassembly, and it will be a bit of a pain to figure them out manually.
Decompiled code
This is what I have so far decompiling this method.
-(UIPreviewAction*)_previewActionForSwipeAction: (unsigned long long)action
withMessage: (id)message
forSwipe: (BOOL)swipe
{
x20 = swipe
x21 = message
x19 = action
x22 = self
x25 = [self presentingViewController];
if (x25 == 0) {
x25 = [[UIApplication] sharedApplication] sceneController];
}
w28 = 0xc2000000 // from "movz w28, #0xc200, lsl #16"; I don't know if that's correct
x8 = x19 - 5 // _shiftedAction = action - 5
if (x8 > 0) goto L1; // if (action > 5)
/* TODO; involves jumptable
000000010009bd34 movz x0, #0x0
000000010009bd38 adr x9, #0x10009c384
000000010009bd3c nop
000000010009bd40 ldrsw x10, [x9, x19, lsl #2]
000000010009bd44 add x9, x10, x9
000000010009bd48 br x9
*/
L1: // 0x10009bd4c
if (x8 > 1) goto L2; // if (action > 6)
// TODO
L2: // 0x10009bdd8
}