571425 - Enable NSLinkEditError logging for pr_LoadMachDyldModule in prlink.c

Status: RESOLVED FIXED

(NSPR :: NSPR, defect)

Description

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

Attachment: port kreeger's NSLinkEditError logging to pr_LoadMachDyldModule, v1.0

This is similar to bug 354248, which implemented NSLinkEditError logging in pr_LoadViaDyld.

As reported in bug 354248 comment 17, we had a module loading error in Camino recently when working on getting it to build against mozilla-central, and the error message we got was rather useless.  Stuart did some searching and he thought the error came through the unpatched codepath.

I've ported Nick's fix for pr_LoadViaDyld to pr_LoadMachDyldModule and verified (via an additional fprintf to stderr, not included in this patch) that, when I duplicated the module failure we hit originally, 1) I'm hitting the pr_LoadMachDyldModule codepath and 2) I'm retrieving error messages from NSLinkEditError, specifically the expected error based on the problem we had.

However, to actually get a useful error message into the XPCOM component loader where Stuart and I would have seen it in our Console when we hit this error, the follow-up work Wan-Teh suggested in bug 354248 comment 16 (or something similar, for the return values for pr_LoadMachDyldModule) is still required.

This is because we were hitting http://mxr.mozilla.org/mozilla-central/source/xpcom/components/nsNativeComponentLoader.cpp#161 and that function's error logging wants to use PR_GetErrorText to retrieve the error; otherwise the error is just the generic unknown error we saw.

I'm afraid that hooking up these error messages to PR_SetErrorText is going to be beyond my abilities, though :(

The attached patch is essentially a straight copy-paste of Nick's patch, with a change to use the right variable name for this method.  It's against whatever NSPR version is on mozilla-central right now.

Comment 1

[Wan-Teh Chang]

Attachment: port kreeger's NSLinkEditError logging to pr_LoadMachDyldModule, v1.1, by Smokey Ardisson

I made a minor edit (reordered variable declarations to
match the order in which they're used) and checked this
in on the NSPR trunk (NSPR 4.8.7).

Checking in prlink.c;
/cvsroot/mozilla/nsprpub/pr/src/linking/prlink.c,v  <--  prlink.c
new revision: 3.109; previous revision: 3.108
done

Comment 2

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

Thanks!

I opened Bug 587535 for the "follow-up work" of getting the messages into PR_SetErrorText (i.e., bug 354248 comment 16 and the second half of comment 0 above), since I didn't see any other bug about those, in case someone else discovers they need those errors.