trace2: prevent segfault on config collection where no value specified

[ad-murray]

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[gitgitgadget]

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[gitgitgadget]

There are issues in commit 2d4ddcf:
add null check for config value
Commit checks stopped - the message is too short
Commit not signed off

[Haizzz]

/allow ad-murray

[gitgitgadget]

User ad-murray is now allowed to use GitGitGadget.

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[gitgitgadget]

There are issues in commit 976bdf6:
Prevent segfault on trace2 config collection where no value specified
Commit checks stopped - the message is too short
Commit not signed off

[gitgitgadget]

There are issues in commit b696097:
trace2: prevent segfault on config collection where no value specified
Commit checks stopped - the message is too short
Commit not signed off

[dscho]

Commit checks stopped - the message is too short

Please follow the guidance in https://github.blog/2022-06-30-write-better-commits-build-better-projects/ to improve it, in particular with a strong focus on this part:

	What you’re doing	Why you’re doing it
High-level (strategic)	Intent (what does this accomplish?)	Context (why does the code do what it does now?)
Low-level (tactical)	Implementation (what did you do to accomplish your goal?)	Justification (why is this change being made?)

In this instance, the commit message could explain, for example, why the !strlen(value) condition is needed, i.e. how a non-NULL but still empty value could lead to a segmentation fault and where in the code that would happen.

Commit not signed off

The Git project requires you to "sign off" your work, please amend the commit accordingly and force-push.

[gitgitgadget]

There are issues in commit 9b505b7:
trace2: prevent segfault on config collection where no value specified
Lines in the body of the commit messages should be wrapped between 60 and 76 characters.
Indented lines, and lines without whitespace, are exempt

[gitgitgadget]

There are issues in commit 48ffb81:
trace2: prevent segfault on config collection where no value specified
Lines in the body of the commit messages should be wrapped between 60 and 76 characters.
Indented lines, and lines without whitespace, are exempt

[ad-murray]

Commit checks stopped - the message is too short

Please follow the guidance in https://github.blog/2022-06-30-write-better-commits-build-better-projects/ to improve it, in particular with a strong focus on this part:

  What you’re doing Why you’re doing it
High-level (strategic) Intent (what does this accomplish?) Context (why does the code do what it does now?)
Low-level (tactical) Implementation (what did you do to accomplish your goal?) Justification (why is this change being made?)
In this instance, the commit message could explain, for example, why the !strlen(value) condition is needed, i.e. how a non-NULL but still empty value could lead to a segmentation fault and where in the code that would happen.

Commit not signed off

The Git project requires you to "sign off" your work, please amend the commit accordingly and force-push.

Commit message updated, is there a way to re-run the failing checks?

[dscho]

is there a way to re-run the failing checks?

Well, those checks fail because the patch introduces a regression. In particular t1300.131 documents that git -c foo.flag config --bool foo.flag should return true, not an error.

Speaking of test cases: You described one in the commit message. How about moving it from the commit message into an actual test script, to verify that the described regression is fixed (and to prevent future regressions going unnoticed)? t0210-trace2-normal.sh would make for a fine home for that test case.

As to the fix for the segmentation fault: I think this diff, or a variation thereof, should be the correct fix:

diff --git a/trace2.c b/trace2.c
index f894532d0533..6cae41ca61c4 100644
--- a/trace2.c
+++ b/trace2.c
@@ -259,7 +259,7 @@ static const char *redact_arg(const char *arg)
 	const char *p, *colon;
 	size_t at;
 
-	if (!trace2_redact ||
+	if (!trace2_redact || !arg ||
 	    (!skip_prefix(arg, "https://", &p) &&
 	     !skip_prefix(arg, "http://", &p)))
 		return arg;

[ad-murray]

right you are, will do