From: Junio C Hamano <gitster@pobox•com>
To: git@vger•kernel.org
Cc: Yuxuan Shui <yshuiv7@gmail•com>
Subject: Re: [PATCH v3 2/2] fsck.c: Rewrite fsck_commit() to use skip_prefix()
Date: Thu, 13 Mar 2014 12:42:36 -0700 [thread overview]
Message-ID: <xmqq38ilj36b.fsf@gitster.dls.corp.google.com> (raw)
In-Reply-To: <xmqq7g7xj4hz.fsf@gitster.dls.corp.google.com> (Junio C. Hamano's message of "Thu, 13 Mar 2014 12:14:00 -0700")
Junio C Hamano <gitster@pobox•com> writes:
>> - if (memcmp(buffer, "tree ", 5))
>> + buffer = skip_prefix(buffer, "tree ");
>> + if (buffer == NULL)
>
> We encourage people to write this as:
>
> if (!buffer)
>
> The same comment applies to other new lines in this patch.
I also see a lot of repetitions in the code, before or after the
patch. I wonder if a further refactoring along this line on top of
these two patches might be worth considering.
No, I am not proud of sneaking tree_sha1[] array pointers as a
seemingly boolean-looking must-match-header parameter into the
helper, but this is merely a "how about going in this direction"
weather-balloon patch, so....
fsck.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++------------------
1 file changed, 61 insertions(+), 22 deletions(-)
diff --git a/fsck.c b/fsck.c
index 6aab23b..a3eea7f 100644
--- a/fsck.c
+++ b/fsck.c
@@ -279,10 +279,55 @@ static int fsck_ident(const char **ident, struct object *obj, fsck_error error_f
return 0;
}
+static int fsck_object_line(struct commit *commit, fsck_error error_func,
+ const char **buffer, const char *header,
+ unsigned char must_match_header[])
+{
+ unsigned char sha1_buf[20];
+ unsigned char *sha1 = must_match_header ? must_match_header : sha1_buf;
+ const char *buf;
+
+ buf = skip_prefix(*buffer, header);
+ if (!buf) {
+ if (must_match_header)
+ return error_func(&commit->object, FSCK_ERROR,
+ "invalid format - expected '%.*s' line",
+ (int) strlen(header) - 1,
+ header);
+ return 1;
+ }
+ if (get_sha1_hex(buf, sha1) || buf[40] != '\n')
+ return error_func(&commit->object, FSCK_ERROR,
+ "invalid '%.*s' line format - bad sha1",
+ (int) strlen(header) - 1,
+ header);
+ *buffer = buf + 41;
+ return 0;
+}
+
+static int fsck_ident_line(struct commit *commit, fsck_error error_func,
+ const char **buffer, const char *header)
+{
+ const char *buf;
+ int err;
+
+ buf = skip_prefix(*buffer, header);
+ if (!buf)
+ return error_func(&commit->object, FSCK_ERROR,
+ "invalid format - expected '%.*s' line",
+ (int) strlen(header) - 1,
+ header);
+ err = fsck_ident(&buf, &commit->object, error_func);
+ if (err)
+ return err;
+ *buffer = buf;
+ return 0;
+}
+
static int fsck_commit(struct commit *commit, fsck_error error_func)
{
- const char *buffer = commit->buffer, *tmp;
- unsigned char tree_sha1[20], sha1[20];
+ const char *buffer = commit->buffer;
+ unsigned char tree_sha1[20];
struct commit_graft *graft;
int parents = 0;
int err;
@@ -290,18 +335,17 @@ static int fsck_commit(struct commit *commit, fsck_error error_func)
if (commit->date == ULONG_MAX)
return error_func(&commit->object, FSCK_ERROR, "invalid author/committer line");
- buffer = skip_prefix(buffer, "tree ");
- if (!buffer)
- return error_func(&commit->object, FSCK_ERROR, "invalid format - expected 'tree' line");
- if (get_sha1_hex(buffer, tree_sha1) || buffer[40] != '\n')
- return error_func(&commit->object, FSCK_ERROR, "invalid 'tree' line format - bad sha1");
- buffer += 41;
- while ((tmp = skip_prefix(buffer, "parent "))) {
- buffer = tmp;
- if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n')
- return error_func(&commit->object, FSCK_ERROR, "invalid 'parent' line format - bad sha1");
- buffer += 41;
- parents++;
+ err = fsck_object_line(commit, error_func, &buffer, "tree ", tree_sha1);
+ if (err)
+ return err;
+ while (1) {
+ err = fsck_object_line(commit, error_func, &buffer, "parent ", NULL);
+ if (err < 0)
+ return err;
+ else if (!err)
+ parents++;
+ else
+ break;
}
graft = lookup_commit_graft(commit->object.sha1);
if (graft) {
@@ -324,16 +368,11 @@ static int fsck_commit(struct commit *commit, fsck_error error_func)
if (p || parents)
return error_func(&commit->object, FSCK_ERROR, "parent objects missing");
}
- buffer = skip_prefix(buffer, "author ");
- if (!buffer)
- return error_func(&commit->object, FSCK_ERROR, "invalid format - expected 'author' line");
- err = fsck_ident(&buffer, &commit->object, error_func);
+
+ err = fsck_ident_line(commit, error_func, &buffer, "author ");
if (err)
return err;
- buffer = skip_prefix(buffer, "committer ");
- if (!buffer)
- return error_func(&commit->object, FSCK_ERROR, "invalid format - expected 'committer' line");
- err = fsck_ident(&buffer, &commit->object, error_func);
+ err = fsck_ident_line(commit, error_func, &buffer, "committer ");
if (err)
return err;
if (!commit->tree)
prev parent reply other threads:[~2014-03-13 19:42 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-13 4:45 [PATCH v3 0/2] GSoC micro project, rewrite fsck_commit() to use skip_prefix() Yuxuan Shui
2014-03-13 4:45 ` [PATCH v3 1/2] fsck.c: Change the type of fsck_ident()'s first argument Yuxuan Shui
2014-03-13 19:11 ` Junio C Hamano
2014-03-13 4:45 ` [PATCH v3 2/2] fsck.c: Rewrite fsck_commit() to use skip_prefix() Yuxuan Shui
2014-03-13 19:14 ` Junio C Hamano
2014-03-13 19:42 ` Junio C Hamano [this message]
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