Am 30.09.19 um 23:10 schrieb Elijah Newren:
> If our input stream includes a tag which is later deleted, we were not
> properly deleting it. We did have a step which would delete it, but we
> left a tag in the tag list noting that it needed to be updated, and the
> updating of annotated tags occurred AFTER ref deletion. So, when we
> record that a tag needs to be deleted, also remove it from the list of
> annotated tags to update.
>
> While this has likely been something that has not happened in practice,
> it will come up more in order to support nested tags. For nested tags,
> we either need to give temporary names to the intermediate tags and then
> delete them, or else we need to use the final name for the intermediate
> tags. If we use the final name for the intermediate tags, then in order
> to keep the sanity check that someone doesn't try to update the same tag
> twice, we need to delete the ref after creating the intermediate tag.
> So, either way nested tags imply the need to delete temporary inner tag
> references.
>
> Signed-off-by: Elijah Newren <newren@xxxxxxxxx>
> ---
> fast-import.c | 29 +++++++++++++++++++++++++++++
> t/t9300-fast-import.sh | 13 +++++++++++++
> 2 files changed, 42 insertions(+)
>
> diff --git a/fast-import.c b/fast-import.c
> index b44d6a467e..546da3a938 100644
> --- a/fast-import.c
> +++ b/fast-import.c
> @@ -2793,6 +2793,35 @@ static void parse_reset_branch(const char *arg)
> b = new_branch(arg);
> read_next_command();
> parse_from(b);
> + if (b->delete && !strncmp(b->name, "refs/tags/", 10)) {
b->name is a NUL-terminated string; starts_with() could be used to avoid
the magic number 10.
> + /*
> + * Elsewhere, we call dump_branches() before dump_tags(),
> + * and dump_branches() will handle ref deletions first, so
> + * in order to make sure the deletion actually takes effect,
> + * we need to remove the tag from our list of tags to update.
> + *
> + * NEEDSWORK: replace list of tags with hashmap for faster
> + * deletion?
> + */
> + struct strbuf tag_name = STRBUF_INIT;
This adds a small memory leak.
> + struct tag *t, *prev = NULL;
> + for (t = first_tag; t; t = t->next_tag) {
> + strbuf_reset(&tag_name);
> + strbuf_addf(&tag_name, "refs/tags/%s", t->name);
> + if (!strcmp(b->name, tag_name.buf))
So the strbuf is used to prefix t->name with "refs/tags/", which we know
b->name starts with, and to compare the result with b->name. Removing
the "refs/tags/" prefix from b->name using skip_prefix() and comparing
the result with t->name would be easier.
> + break;
> + prev = t;
> + }
> + if (t) {
> + if (prev)
> + prev->next_tag = t->next_tag;
> + else
> + first_tag = t->next_tag;
> + if (!t->next_tag)
> + last_tag = prev;
> + /* There is no mem_pool_free(t) function to call. */
> + }
> + }
> if (command_buf.len > 0)
> unread_command_buf = 1;
> }
Here's a squashable patch for that:
---
fast-import.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/fast-import.c b/fast-import.c
index 70cd3f0ff4..a109591406 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -2779,6 +2779,7 @@ static void parse_new_tag(const char *arg)
static void parse_reset_branch(const char *arg)
{
struct branch *b;
+ const char *tag_name;
b = lookup_branch(arg);
if (b) {
@@ -2794,7 +2795,7 @@ static void parse_reset_branch(const char *arg)
b = new_branch(arg);
read_next_command();
parse_from(b);
- if (b->delete && !strncmp(b->name, "refs/tags/", 10)) {
+ if (b->delete && skip_prefix(b->name, "refs/tags/", &tag_name)) {
/*
* Elsewhere, we call dump_branches() before dump_tags(),
* and dump_branches() will handle ref deletions first, so
@@ -2804,12 +2805,9 @@ static void parse_reset_branch(const char *arg)
* NEEDSWORK: replace list of tags with hashmap for faster
* deletion?
*/
- struct strbuf tag_name = STRBUF_INIT;
struct tag *t, *prev = NULL;
for (t = first_tag; t; t = t->next_tag) {
- strbuf_reset(&tag_name);
- strbuf_addf(&tag_name, "refs/tags/%s", t->name);
- if (!strcmp(b->name, tag_name.buf))
+ if (!strcmp(t->name, tag_name))
break;
prev = t;
}
--
2.23.0
