From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCH 0/3] avoiding unintended consequences of git_path() usage
Date: Wed, 16 Nov 2011 02:59:44 -0600
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Cc: Ramkumar Ramachandra <artagnon@gmail.com>,
	Junio C Hamano <gitster@pobox.com>,
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To: Nguyen Thai Ngoc Duy <pclouds@gmail.com>
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Nguyen Thai Ngoc Duy wrote:

> Or perhaps
[...]
>  - git_path(const char *path) maintains a small hash table to keep
> track of all returned strings based with "path" as key.
>
> Out of 142 git_path() calls in my tree, 97 of them are in form
> git_path("some static string").

The main bit I dislike about patch 3/3 is that constructs like
'unlink(git_path("MERGE_HEAD"));' are not actually unsafe, unless they
happen to sit in the middle of an unsafe

	const char *filename = git_path(foo);
	int fd;

	call_a_function_i_dont_control();
	fd = open(filename, O_CREAT|O_WRONLY|O_TRUNC, 0600);

sequence.  Lacks that feeling of truth in advertising.  And on the
other hand that this doesn't help with thread-safety at all.

I think if I ran the world, the fundamental operation would be
strbuf_addpath().  Unlike git_pathdup(), this lets callers avoid some
allocation churn if they are in the middle of a loop.