The handle_revision_arg function is rather long, and a big
chunk of it is handling the range operators. Let's pull that
out to a separate helper. While we're doing so, we can clean
up a few of the rough edges that made the flow hard to
follow:
- instead of manually restoring *dotdot (that we overwrote
with a NUL), do the real work in a sub-helper, which
makes it clear that the munge/restore lines are a
matched pair
- eliminate a goto which wasn't actually used for control
flow, but only to avoid duplicating a few lines
(instead, those lines are pushed into another helper
function)
- use early returns instead of deep nesting
- consistently name all variables for the left-hand side
of the range as "a" (rather than "this" or "from") and
the right-hand side as "b" (rather than "next", or using
the unadorned "sha1" or "flags" from the main function).
Signed-off-by: Jeff King <p...@peff.net>
---
revision.c | 177 +++++++++++++++++++++++++++++++++++--------------------------
1 file changed, 102 insertions(+), 75 deletions(-)
diff --git a/revision.c b/revision.c
index dec06ff8b..eb45501fd 100644
--- a/revision.c
+++ b/revision.c
@@ -1429,10 +1429,109 @@ static void prepare_show_merge(struct rev_info *revs)
revs->limited = 1;
}
+static int dotdot_missing(const char *arg, char *dotdot,
+ struct rev_info *revs, int symmetric)
+{
+ if (revs->ignore_missing)
+ return 0;
+ /* de-munge so we report the full argument */
+ *dotdot = '.';
+ die(symmetric
+ ? "Invalid symmetric difference expression %s"
+ : "Invalid revision range %s", arg);
+}
+
+static int handle_dotdot_1(const char *arg, char *dotdot,
+ struct rev_info *revs, int flags,
+ int cant_be_filename)
+{
+ const char *a_name, *b_name;
+ struct object_id a_oid, b_oid;
+ struct object *a_obj, *b_obj;
+ unsigned int a_flags, b_flags;
+ int symmetric = 0;
+ unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
+
+ a_name = arg;
+ if (!*a_name)
+ a_name = "HEAD";
+
+ b_name = dotdot + 2;
+ if (*b_name == '.') {
+ symmetric = 1;
+ b_name++;
+ }
+ if (!*b_name)
+ b_name = "HEAD";
+
+ if (get_sha1_committish(a_name, a_oid.hash) ||
+ get_sha1_committish(b_name, b_oid.hash))
+ return -1;
+
+ if (!cant_be_filename) {
+ *dotdot = '.';
+ verify_non_filename(revs->prefix, arg);
+ *dotdot = '\0';
+ }
+
+ a_obj = parse_object(a_oid.hash);
+ b_obj = parse_object(b_oid.hash);
+ if (!a_obj || !b_obj)
+ return dotdot_missing(arg, dotdot, revs, symmetric);
+
+ if (!symmetric) {
+ /* just A..B */
+ b_flags = flags;
+ a_flags = flags_exclude;
+ } else {
+ /* A...B -- find merge bases between the two */
+ struct commit *a, *b;
+ struct commit_list *exclude;
+
+ a = lookup_commit_reference(a_obj->oid.hash);
+ b = lookup_commit_reference(b_obj->oid.hash);
+ if (!a || !b)
+ return dotdot_missing(arg, dotdot, revs, symmetric);
+
+ exclude = get_merge_bases(a, b);
+ add_rev_cmdline_list(revs, exclude, REV_CMD_MERGE_BASE,
+ flags_exclude);
+ add_pending_commit_list(revs, exclude, flags_exclude);
+ free_commit_list(exclude);
+
+ b_flags = flags;
+ a_flags = flags | SYMMETRIC_LEFT;
+ }
+
+ a_obj->flags |= a_flags;
+ b_obj->flags |= b_flags;
+ add_rev_cmdline(revs, a_obj, a_name, REV_CMD_LEFT, a_flags);
+ add_rev_cmdline(revs, b_obj, b_name, REV_CMD_RIGHT, b_flags);
+ add_pending_object(revs, a_obj, a_name);
+ add_pending_object(revs, b_obj, b_name);
+ return 0;
+}
+
+static int handle_dotdot(const char *arg,
+ struct rev_info *revs, int flags,
+ int cant_be_filename)
+{
+ char *dotdot = strstr(arg, "..");
+ int ret;
+
+ if (!dotdot)
+ return -1;
+
+ *dotdot = '\0';
+ ret = handle_dotdot_1(arg, dotdot, revs, flags, cant_be_filename);
+ *dotdot = '.';
+
+ return ret;
+}
+
int handle_revision_arg(const char *arg_, struct rev_info *revs, int flags,
unsigned revarg_opt)
{
struct object_context oc;
- char *dotdot;
char *mark;
struct object *object;
unsigned char sha1[20];
@@ -1451,80 +1550,8 @@ int handle_revision_arg(const char *arg_, struct
rev_info *revs, int flags, unsi
return -1;
}
- dotdot = strstr(arg, "..");
- if (dotdot) {
- unsigned char from_sha1[20];
- const char *next = dotdot + 2;
- const char *this = arg;
- int symmetric = *next == '.';
- unsigned int flags_exclude = flags ^ (UNINTERESTING | BOTTOM);
- unsigned int a_flags;
-
- *dotdot = 0;
- next += symmetric;
-
- if (!*next)
- next = "HEAD";
- if (dotdot == arg)
- this = "HEAD";
- if (!get_sha1_committish(this, from_sha1) &&
- !get_sha1_committish(next, sha1)) {
- struct object *a_obj, *b_obj;
-
- if (!cant_be_filename) {
- *dotdot = '.';
- verify_non_filename(revs->prefix, arg);
- *dotdot = '\0';
- }
-
- a_obj = parse_object(from_sha1);
- b_obj = parse_object(sha1);
- if (!a_obj || !b_obj) {
- missing:
- *dotdot = '.';
- if (revs->ignore_missing)
- return 0;
- die(symmetric
- ? "Invalid symmetric difference expression
%s"
- : "Invalid revision range %s", arg);
- }
-
- if (!symmetric) {
- /* just A..B */
- a_flags = flags_exclude;
- } else {
- /* A...B -- find merge bases between the two */
- struct commit *a, *b;
- struct commit_list *exclude;
-
- a = lookup_commit_reference(a_obj->oid.hash);
- b = lookup_commit_reference(b_obj->oid.hash);
- if (!a || !b)
- goto missing;
- exclude = get_merge_bases(a, b);
- add_rev_cmdline_list(revs, exclude,
- REV_CMD_MERGE_BASE,
- flags_exclude);
- add_pending_commit_list(revs, exclude,
- flags_exclude);
- free_commit_list(exclude);
-
- a_flags = flags | SYMMETRIC_LEFT;
- }
-
- a_obj->flags |= a_flags;
- b_obj->flags |= flags;
- add_rev_cmdline(revs, a_obj, this,
- REV_CMD_LEFT, a_flags);
- add_rev_cmdline(revs, b_obj, next,
- REV_CMD_RIGHT, flags);
- add_pending_object(revs, a_obj, this);
- add_pending_object(revs, b_obj, next);
- *dotdot = '.';
- return 0;
- }
- *dotdot = '.';
- }
+ if (!handle_dotdot(arg, revs, flags, revarg_opt))
+ return 0;
mark = strstr(arg, "^@");
if (mark && !mark[2]) {
--
2.13.0.219.g63f6bc368
