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[PATCH 2/2] use MOVE_ARRAY

From
René Scharfe <l.s.r@web.de>
Date
Apr 7, 2017, 15:25 UTC
Message-ID
<c4bdb724-62d5-056d-0667-09e446bb3119@web.de>
In-Reply-To
<96beb4c6-0569-0c12-8151-462c20be6a2a@suse.cz>

Add a semantic patch for converting certain calls of memmove(3) to MOVE_ARRAY() and apply that transformation to the code base. The result is shorter and safer code.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
---
 apply.c                        |  7 +++----
 builtin/ls-files.c             |  3 +--
 builtin/merge.c                |  2 +-
 builtin/pack-objects.c         |  5 ++---
 cache-tree.c                   |  5 ++---
 commit.c                       | 11 ++++-------
 contrib/coccinelle/array.cocci | 37 +++++++++++++++++++++++++++++++++++++
 diffcore-rename.c              |  8 ++++----
 dir.c                          |  4 ++--
 notes-merge.c                  |  3 +--
 parse-options.c                |  2 +-
 read-cache.c                   |  5 ++---
 reflog-walk.c                  |  7 +++----
 refs/files-backend.c           |  5 ++---
 replace_object.c               |  6 ++----
 rerere.c                       |  4 ++--
 string-list.c                  |  5 ++---
 17 files changed, 71 insertions(+), 48 deletions(-)
diff --git a/apply.c b/apply.c
index e6dbab26ad..4e4d13cacc 100644
--- a/apply.c
+++ b/apply.c
@@ -2798,10 +2798,9 @@ static void update_image(struct apply_state *state,
 		img->line_allocated = img->line;
 	}
 	if (preimage_limit != postimage->nr)
-		memmove(img->line + applied_pos + postimage->nr,
-			img->line + applied_pos + preimage_limit,
-			(img->nr - (applied_pos + preimage_limit)) *
-			sizeof(*img->line));
+		MOVE_ARRAY(img->line + applied_pos + postimage->nr,
+			   img->line + applied_pos + preimage_limit,
+			   img->nr - (applied_pos + preimage_limit));
 	memcpy(img->line + applied_pos,
 	       postimage->line,
 	       postimage->nr * sizeof(*img->line));
diff --git a/builtin/ls-files.c b/builtin/ls-files.c
index d449e46db5..1627c26466 100644
--- a/builtin/ls-files.c
+++ b/builtin/ls-files.c
@@ -391,8 +391,7 @@ static void prune_cache(const char *prefix, size_t prefixlen)
 		}
 		last = next;
 	}
-	memmove(active_cache, active_cache + pos,
-		(last - pos) * sizeof(struct cache_entry *));
+	MOVE_ARRAY(active_cache, active_cache + pos, last - pos);
 	active_nr = last - pos;
 }
 
diff --git a/builtin/merge.c b/builtin/merge.c
index 95572b1810..0c0d2e4a94 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -536,7 +536,7 @@ static void parse_branch_merge_options(char *bmo)
 		die(_("Bad branch.%s.mergeoptions string: %s"), branch,
 		    split_cmdline_strerror(argc));
 	REALLOC_ARRAY(argv, argc + 2);
-	memmove(argv + 1, argv, sizeof(*argv) * (argc + 1));
+	MOVE_ARRAY(argv + 1, argv, argc + 1);
 	argc++;
 	argv[0] = "branch.*.mergeoptions";
 	parse_options(argc, argv, NULL, builtin_merge_options,
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 84af7c2324..5fb5d7c546 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -1292,9 +1292,8 @@ static int check_pbase_path(unsigned hash)
 		   done_pbase_paths_alloc);
 	done_pbase_paths_num++;
 	if (pos < done_pbase_paths_num)
-		memmove(done_pbase_paths + pos + 1,
-			done_pbase_paths + pos,
-			(done_pbase_paths_num - pos - 1) * sizeof(unsigned));
+		MOVE_ARRAY(done_pbase_paths + pos + 1, done_pbase_paths + pos,
+			   done_pbase_paths_num - pos - 1);
 	done_pbase_paths[pos] = hash;
 	return 0;
 }
diff --git a/cache-tree.c b/cache-tree.c
index 345ea35963..071164a2ec 100644
--- a/cache-tree.c
+++ b/cache-tree.c
@@ -131,9 +131,8 @@ static int do_invalidate_path(struct cache_tree *it, const char *path)
 			 * move 4 and 5 up one place (2 entries)
 			 * 2 = 6 - 3 - 1 = subtree_nr - pos - 1
 			 */
-			memmove(it->down+pos, it->down+pos+1,
-				sizeof(struct cache_tree_sub *) *
-				(it->subtree_nr - pos - 1));
+			MOVE_ARRAY(it->down + pos, it->down + pos + 1,
+				   it->subtree_nr - pos - 1);
 			it->subtree_nr--;
 		}
 		return 1;
diff --git a/commit.c b/commit.c
index 73c78c2b80..62a71fee92 100644
--- a/commit.c
+++ b/commit.c
@@ -125,10 +125,8 @@ int register_commit_graft(struct commit_graft *graft, int ignore_dups)
 	ALLOC_GROW(commit_graft, commit_graft_nr + 1, commit_graft_alloc);
 	commit_graft_nr++;
 	if (pos < commit_graft_nr)
-		memmove(commit_graft + pos + 1,
-			commit_graft + pos,
-			(commit_graft_nr - pos - 1) *
-			sizeof(*commit_graft));
+		MOVE_ARRAY(commit_graft + pos + 1, commit_graft + pos,
+			   commit_graft_nr - pos - 1);
 	commit_graft[pos] = graft;
 	return 0;
 }
@@ -222,9 +220,8 @@ int unregister_shallow(const unsigned char *sha1)
 	if (pos < 0)
 		return -1;
 	if (pos + 1 < commit_graft_nr)
-		memmove(commit_graft + pos, commit_graft + pos + 1,
-				sizeof(struct commit_graft *)
-				* (commit_graft_nr - pos - 1));
+		MOVE_ARRAY(commit_graft + pos, commit_graft + pos + 1,
+			   commit_graft_nr - pos - 1);
 	commit_graft_nr--;
 	return 0;
 }
diff --git a/contrib/coccinelle/array.cocci b/contrib/coccinelle/array.cocci
index 4ba98b7eaf..a6e5ee927f 100644
--- a/contrib/coccinelle/array.cocci
+++ b/contrib/coccinelle/array.cocci
@@ -27,6 +27,43 @@ expression n;
 
 @@
 type T;
+T *dst;
+T *src;
+expression n;
+@@
+(
+- memmove(
++ MOVE_ARRAY(
+(
+  dst
+|
+  dst + ...
+|
+  &dst[...]
+)
+- , src, (n) * sizeof(*dst)
++ , src, n
+  );
+|
+- memmove(dst,
++ MOVE_ARRAY(dst,
+(
+  src
+|
+  src + ...
+|
+  &src[...]
+)
+- , (n) * sizeof(*src)
++ , n
+  );
+|
+- memmove(dst, src, (n) * sizeof(T));
++ MOVE_ARRAY(dst, src, n);
+)
+
+@@
+type T;
 T *ptr;
 expression n;
 @@
diff --git a/diffcore-rename.c b/diffcore-rename.c
index f7444c86bd..449d5f065f 100644
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -57,8 +57,8 @@ static int add_rename_dst(struct diff_filespec *two)
 	ALLOC_GROW(rename_dst, rename_dst_nr + 1, rename_dst_alloc);
 	rename_dst_nr++;
 	if (first < rename_dst_nr)
-		memmove(rename_dst + first + 1, rename_dst + first,
-			(rename_dst_nr - first - 1) * sizeof(*rename_dst));
+		MOVE_ARRAY(rename_dst + first + 1, rename_dst + first,
+			   rename_dst_nr - first - 1);
 	rename_dst[first].two = alloc_filespec(two->path);
 	fill_filespec(rename_dst[first].two, two->oid.hash, two->oid_valid,
 		      two->mode);
@@ -98,8 +98,8 @@ static struct diff_rename_src *register_rename_src(struct diff_filepair *p)
 	ALLOC_GROW(rename_src, rename_src_nr + 1, rename_src_alloc);
 	rename_src_nr++;
 	if (first < rename_src_nr)
-		memmove(rename_src + first + 1, rename_src + first,
-			(rename_src_nr - first - 1) * sizeof(*rename_src));
+		MOVE_ARRAY(rename_src + first + 1, rename_src + first,
+			   rename_src_nr - first - 1);
 	rename_src[first].p = p;
 	rename_src[first].score = score;
 	return &(rename_src[first]);
diff --git a/dir.c b/dir.c
index f451bfa48c..f5f5658b1d 100644
--- a/dir.c
+++ b/dir.c
@@ -691,8 +691,8 @@ static struct untracked_cache_dir *lookup_untracked(struct untracked_cache *uc,
 	FLEX_ALLOC_MEM(d, name, name, len);
 
 	ALLOC_GROW(dir->dirs, dir->dirs_nr + 1, dir->dirs_alloc);
-	memmove(dir->dirs + first + 1, dir->dirs + first,
-		(dir->dirs_nr - first) * sizeof(*dir->dirs));
+	MOVE_ARRAY(dir->dirs + first + 1, dir->dirs + first,
+		   dir->dirs_nr - first);
 	dir->dirs_nr++;
 	dir->dirs[first] = d;
 	return d;
diff --git a/notes-merge.c b/notes-merge.c
index 5998605acc..36d5d2f87f 100644
--- a/notes-merge.c
+++ b/notes-merge.c
@@ -99,8 +99,7 @@ static struct notes_merge_pair *find_notes_merge_pair_pos(
 	else {
 		*occupied = 0;
 		if (insert_new && i < len) {
-			memmove(list + i + 1, list + i,
-				(len - i) * sizeof(struct notes_merge_pair));
+			MOVE_ARRAY(list + i + 1, list + i, len - i);
 			memset(list + i, 0, sizeof(struct notes_merge_pair));
 		}
 	}
diff --git a/parse-options.c b/parse-options.c
index a23a1e67f0..b8f768b0d8 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -524,7 +524,7 @@ int parse_options_step(struct parse_opt_ctx_t *ctx,
 
 int parse_options_end(struct parse_opt_ctx_t *ctx)
 {
-	memmove(ctx->out + ctx->cpidx, ctx->argv, ctx->argc * sizeof(*ctx->out));
+	MOVE_ARRAY(ctx->out + ctx->cpidx, ctx->argv, ctx->argc);
 	ctx->out[ctx->cpidx + ctx->argc] = NULL;
 	return ctx->cpidx + ctx->argc;
 }
diff --git a/read-cache.c b/read-cache.c
index e447751823..1bb5e97979 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -514,9 +514,8 @@ int remove_index_entry_at(struct index_state *istate, int pos)
 	istate->cache_nr--;
 	if (pos >= istate->cache_nr)
 		return 0;
-	memmove(istate->cache + pos,
-		istate->cache + pos + 1,
-		(istate->cache_nr - pos) * sizeof(struct cache_entry *));
+	MOVE_ARRAY(istate->cache + pos, istate->cache + pos + 1,
+		   istate->cache_nr - pos);
 	return 1;
 }
 
diff --git a/reflog-walk.c b/reflog-walk.c
index 99679f5825..25c198b9fd 100644
--- a/reflog-walk.c
+++ b/reflog-walk.c
@@ -95,10 +95,9 @@ static struct commit_info *get_commit_info(struct commit *commit,
 			struct commit_info *result = &lifo->items[i];
 			if (pop) {
 				if (i + 1 < lifo->nr)
-					memmove(lifo->items + i,
-						lifo->items + i + 1,
-						(lifo->nr - i) *
-						sizeof(struct commit_info));
+					MOVE_ARRAY(lifo->items + i,
+						   lifo->items + i + 1,
+						   lifo->nr - i);
 				lifo->nr--;
 			}
 			return result;
diff --git a/refs/files-backend.c b/refs/files-backend.c
index 50188e92f9..a851326445 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -437,9 +437,8 @@ static int remove_entry(struct ref_dir *dir, const char *refname)
 		return -1;
 	entry = dir->entries[entry_index];
 
-	memmove(&dir->entries[entry_index],
-		&dir->entries[entry_index + 1],
-		(dir->nr - entry_index - 1) * sizeof(*dir->entries)
+	MOVE_ARRAY(&dir->entries[entry_index], &dir->entries[entry_index + 1],
+		dir->nr - entry_index - 1
 		);
 	dir->nr--;
 	if (dir->sorted > entry_index)
diff --git a/replace_object.c b/replace_object.c
index f0b39f06d5..3e49965d05 100644
--- a/replace_object.c
+++ b/replace_object.c
@@ -44,10 +44,8 @@ static int register_replace_object(struct replace_object *replace,
 	ALLOC_GROW(replace_object, replace_object_nr + 1, replace_object_alloc);
 	replace_object_nr++;
 	if (pos < replace_object_nr)
-		memmove(replace_object + pos + 1,
-			replace_object + pos,
-			(replace_object_nr - pos - 1) *
-			sizeof(*replace_object));
+		MOVE_ARRAY(replace_object + pos + 1, replace_object + pos,
+			   replace_object_nr - pos - 1);
 	replace_object[pos] = replace;
 	return 0;
 }
diff --git a/rerere.c b/rerere.c
index 3bd55caf3b..7410445ba2 100644
--- a/rerere.c
+++ b/rerere.c
@@ -159,8 +159,8 @@ static struct rerere_dir *find_rerere_dir(const char *hex)
 		ALLOC_GROW(rerere_dir, rerere_dir_nr + 1, rerere_dir_alloc);
 		/* ... and add it in. */
 		rerere_dir_nr++;
-		memmove(rerere_dir + pos + 1, rerere_dir + pos,
-			(rerere_dir_nr - pos - 1) * sizeof(*rerere_dir));
+		MOVE_ARRAY(rerere_dir + pos + 1, rerere_dir + pos,
+			   rerere_dir_nr - pos - 1);
 		rerere_dir[pos] = rr_dir;
 		scan_rerere_dir(rr_dir);
 	}
diff --git a/string-list.c b/string-list.c
index 45016ad86d..df64d4c446 100644
--- a/string-list.c
+++ b/string-list.c
@@ -46,9 +46,8 @@ static int add_entry(int insert_at, struct string_list *list, const char *string
 		REALLOC_ARRAY(list->items, list->alloc);
 	}
 	if (index < list->nr)
-		memmove(list->items + index + 1, list->items + index,
-				(list->nr - index)
-				* sizeof(struct string_list_item));
+		MOVE_ARRAY(list->items + index + 1, list->items + index,
+			   list->nr - index);
 	list->items[index].string = list->strdup_strings ?
 		xstrdup(string) : (char *)string;
 	list->items[index].util = NULL;

-- 
2.12.2
Previous: René ScharfeNext: Junio C Hamano
Message 12 of 15 in “Fix nonnull errors reported by UBSAN with GCC 7.”
  1. 1/2 Fix nonnull errors reported by UBSAN with GCC 7.Martin Liška, Apr 6, 2017
  2. Jeff KingApr 6, 2017
  3. Martin LiškaApr 6, 2017
  4. René ScharfeApr 6, 2017
  5. Martin LiškaApr 6, 2017
  6. Johannes SixtApr 6, 2017
  7. René ScharfeApr 6, 2017
  8. Johannes SixtApr 6, 2017
  9. Martin LiškaApr 7, 2017
  10. René ScharfeApr 7, 2017
  11. 1/2 add MOVE_ARRAYRené Scharfe, Apr 7, 2017
  12. 2/2 use MOVE_ARRAYRené Scharfe, Apr 7, 2017
  13. Junio C HamanoApr 17, 2017
  14. Johannes SixtApr 17, 2017
  15. Johannes SchindelinApr 6, 2017

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