oid: is_zero instead of iszero

The only function that is named `issomething` (without underscore) was
`git_oid_iszero`.  Rename it to `git_oid_is_zero` for consistency with
the rest of the library.

Author: ethomson

examples/blame.c

@@ -72,7 +72,7 @@ int lg2_blame(git_repository *repo, int argc, char *argv[])
 	 * Get the raw data inside the blob for output. We use the
 	 * `commitish:path/to/file.txt` format to find it.
 	 */
-	if (git_oid_iszero(&blameopts.newest_commit))
+	if (git_oid_is_zero(&blameopts.newest_commit))
 		strcpy(spec, "HEAD");
 	else
 		git_oid_tostr(spec, sizeof(spec), &blameopts.newest_commit);
@@ -101,7 +101,7 @@ int lg2_blame(git_repository *repo, int argc, char *argv[])
 		if (hunk) {
 			char sig[128] = {0};
 			break_on_null_hunk = 1;
-			
+
 			git_oid_tostr(oid, 10, &hunk->final_commit_id);
 			snprintf(sig, 30, "%s <%s>", hunk->final_signature->name, hunk->final_signature->email);
 

examples/fetch.c

@@ -21,7 +21,7 @@ static int update_cb(const char *refname, const git_oid *a, const git_oid *b, vo
 	git_oid_fmt(b_str, b);
 	b_str[GIT_OID_HEXSZ] = '\0';
 
-	if (git_oid_iszero(a)) {
+	if (git_oid_is_zero(a)) {
 		printf("[new]     %.20s %s\n", b_str, refname);
 	} else {
 		git_oid_fmt(a_str, a);

include/git2/deprecated.h

@@ -271,7 +271,6 @@ GIT_EXTERN(void) giterr_set_oom(void);
  * There is no plan to remove these backward compatibility values at
  * this time.
  */
-/**@{*/
 
 typedef git_cred_sign_cb git_cred_sign_callback;
 typedef git_cred_ssh_interactive_cb git_cred_ssh_interactive_callback;
@@ -292,6 +291,20 @@ typedef git_trace_cb git_trace_callback;
 
 /**@}*/
 
+/** @name Deprecated Object ID Types
+ *
+ * These types are retained for backward compatibility.  The newer
+ * versions of these values should be preferred in all new code.
+ *
+ * There is no plan to remove these backward compatibility values at
+ * this time.
+ */
+/**@{*/
+
+GIT_EXTERN(int) git_oid_iszero(const git_oid *id);
+
+/**@}*/
+
 /** @name Deprecated Transfer Progress Types
  *
  * These types are retained for backward compatibility.  The newer

include/git2/oid.h

@@ -207,7 +207,7 @@ GIT_EXTERN(int) git_oid_strcmp(const git_oid *id, const char *str);
  *
  * @return 1 if all zeros, 0 otherwise.
  */
-GIT_EXTERN(int) git_oid_iszero(const git_oid *id);
+GIT_EXTERN(int) git_oid_is_zero(const git_oid *id);
 
 /**
  * OID Shortener object

src/blame.c

@@ -204,7 +204,7 @@ static int normalize_options(
 	memcpy(out, in, sizeof(git_blame_options));
 
 	/* No newest_commit => HEAD */
-	if (git_oid_iszero(&out->newest_commit)) {
+	if (git_oid_is_zero(&out->newest_commit)) {
 		if (git_reference_name_to_id(&out->newest_commit, repo, "HEAD") < 0) {
 			return -1;
 		}
@@ -408,7 +408,7 @@ int git_blame_file(
 
 static bool hunk_is_bufferblame(git_blame_hunk *hunk)
 {
-	return git_oid_iszero(&hunk->final_commit_id);
+	return git_oid_is_zero(&hunk->final_commit_id);
 }
 
 static int buffer_hunk_cb(

src/diff_file.c

@@ -232,7 +232,7 @@ static int diff_file_content_load_blob(
 	int error = 0;
 	git_odb_object *odb_obj = NULL;
 
-	if (git_oid_iszero(&fc->file->id))
+	if (git_oid_is_zero(&fc->file->id))
 		return 0;
 
 	if (fc->file->mode == GIT_FILEMODE_COMMIT)

src/diff_generate.c

@@ -179,7 +179,7 @@ static int diff_delta__from_one(
 
 	delta->old_file.flags |= GIT_DIFF_FLAG_VALID_ID;
 
-	if (has_old || !git_oid_iszero(&delta->new_file.id))
+	if (has_old || !git_oid_is_zero(&delta->new_file.id))
 		delta->new_file.flags |= GIT_DIFF_FLAG_VALID_ID;
 
 	return diff_insert_delta(diff, delta, matched_pathspec);
@@ -240,7 +240,7 @@ static int diff_delta__from_two(
 		delta->old_file.flags |= GIT_DIFF_FLAG_EXISTS;
 		delta->new_file.flags |= GIT_DIFF_FLAG_EXISTS;
 
-		if (!git_oid_iszero(&new_entry->id))
+		if (!git_oid_is_zero(&new_entry->id))
 			delta->new_file.flags |= GIT_DIFF_FLAG_VALID_ID;
 	}
 
@@ -797,13 +797,13 @@ static int maybe_modified(
 	/* if oids and modes match (and are valid), then file is unmodified */
 	} else if (git_oid_equal(&oitem->id, &nitem->id) &&
 			 omode == nmode &&
-			 !git_oid_iszero(&oitem->id)) {
+			 !git_oid_is_zero(&oitem->id)) {
 		status = GIT_DELTA_UNMODIFIED;
 
 	/* if we have an unknown OID and a workdir iterator, then check some
 	 * circumstances that can accelerate things or need special handling
 	 */
-	} else if (git_oid_iszero(&nitem->id) && new_is_workdir) {
+	} else if (git_oid_is_zero(&nitem->id) && new_is_workdir) {
 		bool use_ctime =
 			((diff->diffcaps & GIT_DIFFCAPS_TRUST_CTIME) != 0);
 		git_index *index = git_iterator_index(info->new_iter);
@@ -843,7 +843,7 @@ static int maybe_modified(
 	/* if we got here and decided that the files are modified, but we
 	 * haven't calculated the OID of the new item, then calculate it now
 	 */
-	if (modified_uncertain && git_oid_iszero(&nitem->id)) {
+	if (modified_uncertain && git_oid_is_zero(&nitem->id)) {
 		const git_oid *update_check =
 			DIFF_FLAG_IS_SET(diff, GIT_DIFF_UPDATE_INDEX) && omode == nmode ?
 			&oitem->id : NULL;
@@ -877,7 +877,7 @@ static int maybe_modified(
 
 	return diff_delta__from_two(
 		diff, status, oitem, omode, nitem, nmode,
-		git_oid_iszero(&noid) ? NULL : &noid, matched_pathspec);
+		git_oid_is_zero(&noid) ? NULL : &noid, matched_pathspec);
 }
 
 static bool entry_is_prefixed(

src/diff_print.c

@@ -325,10 +325,10 @@ static int diff_delta_format_with_paths(
 	const char *oldpath,
 	const char *newpath)
 {
-	if (git_oid_iszero(&delta->old_file.id))
+	if (git_oid_is_zero(&delta->old_file.id))
 		oldpath = "/dev/null";
 
-	if (git_oid_iszero(&delta->new_file.id))
+	if (git_oid_is_zero(&delta->new_file.id))
 		newpath = "/dev/null";
 
 	return git_buf_printf(out, template, oldpath, newpath);
@@ -381,8 +381,8 @@ int diff_delta_format_similarity_header(
 
 static bool delta_is_unchanged(const git_diff_delta *delta)
 {
-	if (git_oid_iszero(&delta->old_file.id) &&
-		git_oid_iszero(&delta->new_file.id))
+	if (git_oid_is_zero(&delta->old_file.id) &&
+		git_oid_is_zero(&delta->new_file.id))
 		return true;
 
 	if (delta->old_file.mode == GIT_FILEMODE_COMMIT ||

src/diff_tform.c

@@ -560,13 +560,13 @@ static int similarity_measure(
 
 	/* if exact match is requested, force calculation of missing OIDs now */
 	if (exact_match) {
-		if (git_oid_iszero(&a_file->id) &&
+		if (git_oid_is_zero(&a_file->id) &&
 			diff->old_src == GIT_ITERATOR_TYPE_WORKDIR &&
 			!git_diff__oid_for_file(&a_file->id,
 				diff, a_file->path, a_file->mode, a_file->size))
 			a_file->flags |= GIT_DIFF_FLAG_VALID_ID;
 
-		if (git_oid_iszero(&b_file->id) &&
+		if (git_oid_is_zero(&b_file->id) &&
 			diff->new_src == GIT_ITERATOR_TYPE_WORKDIR &&
 			!git_diff__oid_for_file(&b_file->id,
 				diff, b_file->path, b_file->mode, b_file->size))

src/filter.c

@@ -385,7 +385,7 @@ uint16_t git_filter_source_filemode(const git_filter_source *src)
 
 const git_oid *git_filter_source_id(const git_filter_source *src)
 {
-	return git_oid_iszero(&src->oid) ? NULL : &src->oid;
+	return git_oid_is_zero(&src->oid) ? NULL : &src->oid;
 }
 
 git_filter_mode_t git_filter_source_mode(const git_filter_source *src)