Re: [PATCH 1/4] attr.c::path_matches(): the basename is part of the pathname

[Duy Nguyen]

On Wed, Mar 27, 2013 at 1:49 AM, Jeff King  wrote:
> On Tue, Mar 26, 2013 at 11:39:28AM -0700, Junio C Hamano wrote:
>
>> The function takes two strings (pathname and basename) as if they
>> are independent strings, but in reality, the latter is always
>> pointing into a substring in the former.
>>
>> Clarify this relationship by expressing the latter as an offset into
>> the former.
>>
>> Signed-off-by: Junio C Hamano 
>
> This is a huge improvement in maintainability. My initial fix attempt
> was to just xstrdup() the strings (knowing that the performance would be
> horrible, but I was still investigating correctness issues at that
> point). And of course I ran into this same issue as I tried to make a
> copy of pathname.
>
> So even without the rest of the fix, this is definitely a good idea. :)

match_{base,path}name and their exclude callers do the same thing. I
guess I'm used to it and did not see the maintainability issue. Maybe
we should do the same there too.
-- 
Duy
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 1/4] attr.c::path_matches(): the basename is part of the pathname

[Jeff King]

On Tue, Mar 26, 2013 at 11:39:28AM -0700, Junio C Hamano wrote:

> The function takes two strings (pathname and basename) as if they
> are independent strings, but in reality, the latter is always
> pointing into a substring in the former.
> 
> Clarify this relationship by expressing the latter as an offset into
> the former.
> 
> Signed-off-by: Junio C Hamano 

This is a huge improvement in maintainability. My initial fix attempt
was to just xstrdup() the strings (knowing that the performance would be
horrible, but I was still investigating correctness issues at that
point). And of course I ran into this same issue as I tried to make a
copy of pathname.

So even without the rest of the fix, this is definitely a good idea. :)

-Peff
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH 1/4] attr.c::path_matches(): the basename is part of the pathname

[Junio C Hamano]

The function takes two strings (pathname and basename) as if they
are independent strings, but in reality, the latter is always
pointing into a substring in the former.

Clarify this relationship by expressing the latter as an offset into
the former.

Signed-off-by: Junio C Hamano 
---
 attr.c | 19 ++-
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/attr.c b/attr.c
index ab2aab2..4cfe0ee 100644
--- a/attr.c
+++ b/attr.c
@@ -655,7 +655,7 @@ static void prepare_attr_stack(const char *path, int dirlen)
 }
 
 static int path_matches(const char *pathname, int pathlen,
-   const char *basename,
+   int basename_offset,
const struct pattern *pat,
const char *base, int baselen)
 {
@@ -667,8 +667,8 @@ static int path_matches(const char *pathname, int pathlen,
return 0;
 
if (pat->flags & EXC_FLAG_NODIR) {
-   return match_basename(basename,
- pathlen - (basename - pathname),
+   return match_basename(pathname + basename_offset,
+ pathlen - basename_offset,
  pattern, prefix,
  pat->patternlen, pat->flags);
}
@@ -701,7 +701,7 @@ static int fill_one(const char *what, struct match_attr *a, 
int rem)
return rem;
 }
 
-static int fill(const char *path, int pathlen, const char *basename,
+static int fill(const char *path, int pathlen, int basename_offset,
struct attr_stack *stk, int rem)
 {
int i;
@@ -711,7 +711,7 @@ static int fill(const char *path, int pathlen, const char 
*basename,
struct match_attr *a = stk->attrs[i];
if (a->is_macro)
continue;
-   if (path_matches(path, pathlen, basename,
+   if (path_matches(path, pathlen, basename_offset,
 &a->u.pat, base, stk->originlen))
rem = fill_one("fill", a, rem);
}
@@ -750,7 +750,8 @@ static void collect_all_attrs(const char *path)
 {
struct attr_stack *stk;
int i, pathlen, rem, dirlen;
-   const char *basename, *cp, *last_slash = NULL;
+   const char *cp, *last_slash = NULL;
+   int basename_offset;
 
for (cp = path; *cp; cp++) {
if (*cp == '/' && cp[1])
@@ -758,10 +759,10 @@ static void collect_all_attrs(const char *path)
}
pathlen = cp - path;
if (last_slash) {
-   basename = last_slash + 1;
+   basename_offset = last_slash + 1 - path;
dirlen = last_slash - path;
} else {
-   basename = path;
+   basename_offset = 0;
dirlen = 0;
}
 
@@ -771,7 +772,7 @@ static void collect_all_attrs(const char *path)
 
rem = attr_nr;
for (stk = attr_stack; 0 < rem && stk; stk = stk->prev)
-   rem = fill(path, pathlen, basename, stk, rem);
+   rem = fill(path, pathlen, basename_offset, stk, rem);
 }
 
 int git_check_attr(const char *path, int num, struct git_attr_check *check)
-- 
1.8.2-350-g3df87a1

--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html