mirrors/git
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

OFFSETOF_VAR macro to simplify hashmap iterators

Browse Source 
While we cannot rely on a `__typeof__' operator being portable
to use with `offsetof'; we can calculate the pointer offset
using an existing pointer and the address of a member using
pointer arithmetic for compilers without `__typeof__'.

This allows us to simplify usage of hashmap iterator macros
by not having to specify a type when a pointer of that type
is already given.

In the future, list iterator macros (e.g. list_for_each_entry)
may also be implemented using OFFSETOF_VAR to save hackers the
trouble of using container_of/list_entry macros and without
relying on non-portable `__typeof__'.

v3: use `__typeof__' to avoid clang warnings

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Eric Wong
2019-10-06 23:30:41 +00:00
committed by Junio C Hamano
parent c8e424c9c9
commit 23dee69f53
15 changed files with 56 additions and 45 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
diffcore-rename.c
View File

@ -284,7 +284,7 @@ static int find_identical_files(struct hashmap *srcs,
*/
p = hashmap_get_entry_from_hash(srcs, hash, NULL,
struct file_similarity, entry);
hashmap_for_each_entry_from(srcs, p, struct file_similarity, entry) {
hashmap_for_each_entry_from(srcs, p, entry) {
int score;
struct diff_filespec *source = p->filespec;