Hi, On Fri, Apr 17, 2015 at 5:41 AM, Eric Sunshine <sunshine@xxxxxxxxxxxxxx> wrote: > On Tue, Apr 14, 2015 at 1:28 PM, Paul Tan <pyokagan@xxxxxxxxx> wrote: >> Below is the fixed patch. I also decided to return NULL if `filename` is >> NULL because such an input usually indicated an uncaught error. > > Unfortunately, this blurs the line between programmer error (passing > NULL for filename) and a user/configuration error (XDG_CONFIG_HOME and > HOME being undefined). If there is indeed no valid interpretation for > filename==NULL, then it may be better to die() or assert() here to > flag the programmer error as early as possible, rather than returning > NULL. > > More below. > >> --- >> diff --git a/cache.h b/cache.h >> index 3d3244b..2db10b8 100644 >> --- a/cache.h >> +++ b/cache.h >> @@ -836,6 +836,14 @@ char *strip_path_suffix(const char *path, const char *suffix); >> int daemon_avoid_alias(const char *path); >> extern int is_ntfs_dotgit(const char *name); >> >> +/** >> + * Returns the newly allocated string "$XDG_CONFIG_HOME/git/{filename}". If >> + * $XDG_CONFIG_HOME is unset or empty, returns the newly allocated string >> + * "$HOME/.config/git/{filename}". Returns NULL if filename is NULL or an error >> + * occurred. >> + */ > > This is better than the original which said "$XDG_CONFIG_HOME/git/%s", > but is still potentially confusing. When I read the earlier iteration, > I was left with the impression that it was returning that literal > string, with '$' and '%s' embedded, and that the caller would have to > process it further to have '$' and '%s' expanded. Perhaps rephrasing > it something like this will help? > > Return a newly allocated string with value xdg+"/git/"+filename > where xdg is the interpolated value of $XDG_CONFIG_HOME if > defined and non-empty, otherwise "$HOME/.config". Return NULL > upon error. > Personally I think interpolated strings are easier to read than concatenated strings. $VARIABLE (all upper case) in shell scripting is understood to be an environment variable, and $variable (all lower case) to be a local variable. Thinking about it again, I should not be using python-style format strings either ;-). So I would write it as "$XDG_CONFIG_HOME/git/$filename". But anyway, I don't have strong opinions on documentation, so I will leave this to majority opinion. I will change it if you strongly disagree :-). > Also, for consistency with other API documentation, say "Return" > rather than "Returns". Okay, will fix. > > More below. > >> +extern char *xdg_config_home(const char *filename); >> + >> /* object replacement */ >> #define LOOKUP_REPLACE_OBJECT 1 >> extern void *read_sha1_file_extended(const unsigned char *sha1, enum object_type *type, unsigned long *size, unsigned flag); >> diff --git a/path.c b/path.c >> index e608993..8ee7191 100644 >> --- a/path.c >> +++ b/path.c >> @@ -856,3 +856,19 @@ int is_ntfs_dotgit(const char *name) >> len = -1; >> } >> } >> + >> +char *xdg_config_home(const char *filename) >> +{ >> + const char *config_home = getenv("XDG_CONFIG_HOME"); >> + >> + if (!filename) >> + return NULL; > > See above regarding conflation of programmer error and user/configuration error. > >> + if (!config_home || !config_home[0]) { > > On this project, *config_home is usually favored over config_home[0]. > >> + const char *home = getenv("HOME"); >> + >> + if (!home) >> + return NULL; >> + return mkpathdup("%s/.config/git/%s", home, filename); >> + } else >> + return mkpathdup("%s/git/%s", config_home, filename); > > This logic is more difficult to follow than it ought to be due to the > use of 'config_home' so distant from the 'if' which checked it, and > due to the nested 'if'. It could be expressed more straight-forwardly > as: > > if (config_home && *config_home) > return mkpathdup("%s/git/%s", config_home, filename); > > home = getenv("HOME"); > if (home) > return mkpathdup("%s/.config/git/%s", home, filename); > > return NULL; > Ah, flipping the conditionals definitely makes it look nicer. I guess I will need your sign off to use your code? Thanks! Regards, Paul -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html