On 18/02/17 00:06, brian m. carlson wrote:
> Convert most leaf functions to struct object_id.  Rewrite several
> hardcoded numbers in terms of GIT_SHA1_HEXSZ, using an intermediate
> variable where that makes sense.
> 
> Signed-off-by: brian m. carlson <sand...@crustytoothpaste.net>
> ---
>  builtin/diff-tree.c | 38 ++++++++++++++++++++------------------
>  1 file changed, 20 insertions(+), 18 deletions(-)
> 
> diff --git a/builtin/diff-tree.c b/builtin/diff-tree.c
> index 8ce00480cd..1f1573bb2a 100644
> --- a/builtin/diff-tree.c
> +++ b/builtin/diff-tree.c
> @@ -7,9 +7,9 @@
>  
>  static struct rev_info log_tree_opt;
>  
> -static int diff_tree_commit_sha1(const unsigned char *sha1)
> +static int diff_tree_commit_sha1(const struct object_id *oid)
>  {
> -     struct commit *commit = lookup_commit_reference(sha1);
> +     struct commit *commit = lookup_commit_reference(oid->hash);
>       if (!commit)
>               return -1;
>       return log_tree_commit(&log_tree_opt, commit);
> @@ -18,22 +18,22 @@ static int diff_tree_commit_sha1(const unsigned char 
> *sha1)
>  /* Diff one or more commits. */
>  static int stdin_diff_commit(struct commit *commit, char *line, int len)
>  {
> -     unsigned char sha1[20];
> -     if (isspace(line[40]) && !get_sha1_hex(line+41, sha1)) {
> +     struct object_id oid;
> +     if (isspace(line[GIT_SHA1_HEXSZ]) && 
> !get_oid_hex(line+GIT_SHA1_HEXSZ+1, &oid)) {
>               /* Graft the fake parents locally to the commit */
> -             int pos = 41;
> +             int pos = GIT_SHA1_HEXSZ + 1;
>               struct commit_list **pptr;
>  
>               /* Free the real parent list */
>               free_commit_list(commit->parents);
>               commit->parents = NULL;
>               pptr = &(commit->parents);
> -             while (line[pos] && !get_sha1_hex(line + pos, sha1)) {
> -                     struct commit *parent = lookup_commit(sha1);
> +             while (line[pos] && !get_oid_hex(line + pos, &oid)) {
> +                     struct commit *parent = lookup_commit(oid.hash);
>                       if (parent) {
>                               pptr = &commit_list_insert(parent, pptr)->next;
>                       }
> -                     pos += 41;
> +                     pos += GIT_SHA1_HEXSZ + 1;
>               }
>       }
>       return log_tree_commit(&log_tree_opt, commit);
> @@ -42,11 +42,13 @@ static int stdin_diff_commit(struct commit *commit, char 
> *line, int len)
>  /* Diff two trees. */
>  static int stdin_diff_trees(struct tree *tree1, char *line, int len)
>  {
> -     unsigned char sha1[20];
> +     struct object_id oid;
>       struct tree *tree2;
> -     if (len != 82 || !isspace(line[40]) || get_sha1_hex(line + 41, sha1))
> +     const int chunksz = GIT_SHA1_HEXSZ + 1;
> +     if (len != 2 * chunksz || !isspace(line[chunksz-1]) ||
> +             get_sha1_hex(line + chunksz, oid.hash))

I'm not sure that this is an improvement. The input expected in 'line'
is supposed to look like: '<sha1> + <space> + <sha1> + <\n>'. So your
'chunk' would be a <sha1> plus one 'char' of some sort. Except that the
caller of this function has already replaced the newline character with
a '\0' char (so strlen(line) would return 81), but still passes the
original line length! Also, note that this (and other functions in this
file) actually test for 'isspace(char)' rather than for a ' ' char!

Hmm, maybe just:

if (len < (2 * GIT_SHA1_HEXSZ + 1) || line[GIT_SHA1_HEXSZ] != ' ' ||
    get_sha1_hex(line + GIT_SHA1_HEXSZ + 1, oid.hash))

(or, perhaps, still call isspace() in this patch ...)

ATB,
Ramsay Jones

>               return error("Need exactly two trees, separated by a space");
> -     tree2 = lookup_tree(sha1);
> +     tree2 = lookup_tree(oid.hash);
>       if (!tree2 || parse_tree(tree2))
>               return -1;
>       printf("%s %s\n", oid_to_hex(&tree1->object.oid),
> @@ -60,15 +62,15 @@ static int stdin_diff_trees(struct tree *tree1, char 
> *line, int len)
>  static int diff_tree_stdin(char *line)
>  {
>       int len = strlen(line);
> -     unsigned char sha1[20];
> +     struct object_id oid;
>       struct object *obj;
>  
>       if (!len || line[len-1] != '\n')
>               return -1;
>       line[len-1] = 0;
> -     if (get_sha1_hex(line, sha1))
> +     if (get_oid_hex(line, &oid))
>               return -1;
> -     obj = parse_object(sha1);
> +     obj = parse_object(oid.hash);
>       if (!obj)
>               return -1;
>       if (obj->type == OBJ_COMMIT)
> @@ -76,7 +78,7 @@ static int diff_tree_stdin(char *line)
>       if (obj->type == OBJ_TREE)
>               return stdin_diff_trees((struct tree *)obj, line, len);
>       error("Object %s is a %s, not a commit or tree",
> -           sha1_to_hex(sha1), typename(obj->type));
> +           oid_to_hex(&oid), typename(obj->type));
>       return -1;
>  }
>  
> @@ -141,7 +143,7 @@ int cmd_diff_tree(int argc, const char **argv, const char 
> *prefix)
>               break;
>       case 1:
>               tree1 = opt->pending.objects[0].item;
> -             diff_tree_commit_sha1(tree1->oid.hash);
> +             diff_tree_commit_sha1(&tree1->oid);
>               break;
>       case 2:
>               tree1 = opt->pending.objects[0].item;
> @@ -164,9 +166,9 @@ int cmd_diff_tree(int argc, const char **argv, const char 
> *prefix)
>                       opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
>                                              DIFF_SETUP_USE_CACHE);
>               while (fgets(line, sizeof(line), stdin)) {
> -                     unsigned char sha1[20];
> +                     struct object_id oid;
>  
> -                     if (get_sha1_hex(line, sha1)) {
> +                     if (get_oid_hex(line, &oid)) {
>                               fputs(line, stdout);
>                               fflush(stdout);
>                       }
> 

Reply via email to