Re: [RFC] introduce GIT_WORK_DIR environment variable

From: Nguyen Thai Ngoc Duy <pclouds@gmail.com>
Date: Mar 11, 2007, 12:42 UTC
Message-ID: <fcaeb9bf0703110542t49bb3e77kb164ba7bfee1a6ed@mail.gmail.com>
In-Reply-To: <20070311043250.GA21331@moooo.ath.cx>

On 3/11/07, Matthias Lederhofer <matled@gmx.net> wrote:

> +               gitwd = getenv(GIT_WORKING_DIR_ENVIRONMENT);
> +               if (!gitwd || stat(gitwd, &st_work))
>                         return NULL;

I propose the following instead of the last two lines:

                if (!gitwd)
                        return NULL;
                if (stat(gitwd, &st_work))
                        die("Unable to stat git working directory %s",gitwd);

Show 24 quoted lines

> +               if (inside_git_dir == -1 && stat(gitdirenv, &st_git))
> +                       die("Unable to stat git directory");
> +               if (!getcwd(cwd, sizeof(cwd)-1) || cwd[0] != '/')
> +                       die("Unable to read current working directory");
> +               len = strlen(cwd);
> +
> +               prefix = cwd+len;
> +               for (;;) {
> +                       c = *prefix;
> +                       *prefix = '\0';
> +                       if (stat(cwd, &st))
> +                               die("Unable to stat '%s'", cwd);
> +                       if (st_work.st_dev == st.st_dev &&
> +                           st_work.st_ino == st.st_ino)
> +                               break;
> +                       if (inside_git_dir == -1 &&
> +                           st_git.st_dev == st.st_dev &&
> +                           st_git.st_ino == st.st_ino)
> +                               inside_git_dir = 1;
> +                       *prefix = c;
> +
> +                       if (prefix == cwd+1) {
> +                               has_working_directory = 0;
> +                               return NULL;

My case seems a bit complicated than usual. The working directory (/home/pclouds/blog/data) was not a prefix of cwd (/home/pclouds/blog) so the code failed silently at this line. If I replace "has_working_directory = 0; return NULL;" with "strcpy(cwd,gitwd);c = 0;break;", it may work but see below

Show 10 quoted lines

> +                       }
> +                       while (*(--prefix) != '/')
> +                               ; /* do nothing */
> +                       if (prefix == cwd)
> +                               prefix++;
> +               }
> +
> +               if (chdir(cwd))
> +                       die("Cannot change directory to '%s'", cwd);
> +

If cwd changed and GIT_DIR is a relative path, git can no longer access GIT_DIR properly.

-- 
Duy