builtin/receive-pack: convert portions to struct object_id

Convert some hardcoded constants into uses of parse_oid_hex.
Additionally, convert all uses of struct command, and miscellaneous
other functions necessary for that.  This work is necessary to be able
to convert sha1_array_append later on.

To avoid needing to specify a constant, reject shallow lines with the
wrong length instead of simply ignoring them.

Note that in queue_command we are guaranteed to have a NUL-terminated
buffer or at least one byte of overflow that we can safely read, so the
linelen check can be elided.  We would die in such a case, but not read
invalid memory.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index feafb076a41d534d4a503247eadb2661f47b3b3f..62b7c5e25c1bc95f41f76d38cb7bd28428cce139 100644 (file)
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -309,8 +309,8 @@ struct command {
        unsigned int skip_update:1,
                     did_not_exist:1;
        int index;
-       unsigned char old_sha1[20];
-       unsigned char new_sha1[20];
+       struct object_id old_oid;
+       struct object_id new_oid;
        char ref_name[FLEX_ARRAY]; /* more */
 };
 
@@ -723,7 +723,7 @@ static int feed_receive_hook(void *state_, const char **bufp, size_t *sizep)
                return -1; /* EOF */
        strbuf_reset(&state->buf);
        strbuf_addf(&state->buf, "%s %s %s\n",
-                   sha1_to_hex(cmd->old_sha1), sha1_to_hex(cmd->new_sha1),
+                   oid_to_hex(&cmd->old_oid), oid_to_hex(&cmd->new_oid),
                    cmd->ref_name);
        state->cmd = cmd->next;
        if (bufp) {
@@ -764,8 +764,8 @@ static int run_update_hook(struct command *cmd)
                return 0;
 
        argv[1] = cmd->ref_name;
-       argv[2] = sha1_to_hex(cmd->old_sha1);
-       argv[3] = sha1_to_hex(cmd->new_sha1);
+       argv[2] = oid_to_hex(&cmd->old_oid);
+       argv[3] = oid_to_hex(&cmd->new_oid);
        argv[4] = NULL;
 
        proc.no_stdin = 1;
@@ -988,8 +988,8 @@ static const char *update(struct command *cmd, struct shallow_info *si)
        const char *name = cmd->ref_name;
        struct strbuf namespaced_name_buf = STRBUF_INIT;
        const char *namespaced_name, *ret;
-       unsigned char *old_sha1 = cmd->old_sha1;
-       unsigned char *new_sha1 = cmd->new_sha1;
+       struct object_id *old_oid = &cmd->old_oid;
+       struct object_id *new_oid = &cmd->new_oid;
 
        /* only refs/... are allowed */
        if (!starts_with(name, "refs/") || check_refname_format(name + 5, 0)) {
@@ -1014,20 +1014,20 @@ static const char *update(struct command *cmd, struct shallow_info *si)
                                refuse_unconfigured_deny();
                        return "branch is currently checked out";
                case DENY_UPDATE_INSTEAD:
-                       ret = update_worktree(new_sha1);
+                       ret = update_worktree(new_oid->hash);
                        if (ret)
                                return ret;
                        break;
                }
        }
 
-       if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
+       if (!is_null_oid(new_oid) && !has_object_file(new_oid)) {
                error("unpack should have generated %s, "
-                     "but I can't find it!", sha1_to_hex(new_sha1));
+                     "but I can't find it!", oid_to_hex(new_oid));
                return "bad pack";
        }
 
-       if (!is_null_sha1(old_sha1) && is_null_sha1(new_sha1)) {
+       if (!is_null_oid(old_oid) && is_null_oid(new_oid)) {
                if (deny_deletes && starts_with(name, "refs/heads/")) {
                        rp_error("denying ref deletion for %s", name);
                        return "deletion prohibited";
@@ -1053,14 +1053,14 @@ static const char *update(struct command *cmd, struct shallow_info *si)
                }
        }
 
-       if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
-           !is_null_sha1(old_sha1) &&
+       if (deny_non_fast_forwards && !is_null_oid(new_oid) &&
+           !is_null_oid(old_oid) &&
            starts_with(name, "refs/heads/")) {
                struct object *old_object, *new_object;
                struct commit *old_commit, *new_commit;
 
-               old_object = parse_object(old_sha1);
-               new_object = parse_object(new_sha1);
+               old_object = parse_object(old_oid->hash);
+               new_object = parse_object(new_oid->hash);
 
                if (!old_object || !new_object ||
                    old_object->type != OBJ_COMMIT ||
@@ -1081,10 +1081,10 @@ static const char *update(struct command *cmd, struct shallow_info *si)
                return "hook declined";
        }
 
-       if (is_null_sha1(new_sha1)) {
+       if (is_null_oid(new_oid)) {
                struct strbuf err = STRBUF_INIT;
-               if (!parse_object(old_sha1)) {
-                       old_sha1 = NULL;
+               if (!parse_object(old_oid->hash)) {
+                       old_oid = NULL;
                        if (ref_exists(name)) {
                                rp_warning("Allowing deletion of corrupt ref.");
                        } else {
@@ -1094,7 +1094,7 @@ static const char *update(struct command *cmd, struct shallow_info *si)
                }
                if (ref_transaction_delete(transaction,
                                           namespaced_name,
-                                          old_sha1,
+                                          old_oid->hash,
                                           0, "push", &err)) {
                        rp_error("%s", err.buf);
                        strbuf_release(&err);
@@ -1111,7 +1111,7 @@ static const char *update(struct command *cmd, struct shallow_info *si)
 
                if (ref_transaction_update(transaction,
                                           namespaced_name,
-                                          new_sha1, old_sha1,
+                                          new_oid->hash, old_oid->hash,
                                           0, "push",
                                           &err)) {
                        rp_error("%s", err.buf);
@@ -1187,8 +1187,8 @@ static void check_aliased_update(struct command *cmd, struct string_list *list)
 
        dst_cmd = (struct command *) item->util;
 
-       if (!hashcmp(cmd->old_sha1, dst_cmd->old_sha1) &&
-           !hashcmp(cmd->new_sha1, dst_cmd->new_sha1))
+       if (!oidcmp(&cmd->old_oid, &dst_cmd->old_oid) &&
+           !oidcmp(&cmd->new_oid, &dst_cmd->new_oid))
                return;
 
        dst_cmd->skip_update = 1;
@@ -1196,11 +1196,11 @@ static void check_aliased_update(struct command *cmd, struct string_list *list)
        rp_error("refusing inconsistent update between symref '%s' (%s..%s) and"
                 " its target '%s' (%s..%s)",
                 cmd->ref_name,
-                find_unique_abbrev(cmd->old_sha1, DEFAULT_ABBREV),
-                find_unique_abbrev(cmd->new_sha1, DEFAULT_ABBREV),
+                find_unique_abbrev(cmd->old_oid.hash, DEFAULT_ABBREV),
+                find_unique_abbrev(cmd->new_oid.hash, DEFAULT_ABBREV),
                 dst_cmd->ref_name,
-                find_unique_abbrev(dst_cmd->old_sha1, DEFAULT_ABBREV),
-                find_unique_abbrev(dst_cmd->new_sha1, DEFAULT_ABBREV));
+                find_unique_abbrev(dst_cmd->old_oid.hash, DEFAULT_ABBREV),
+                find_unique_abbrev(dst_cmd->new_oid.hash, DEFAULT_ABBREV));
 
        cmd->error_string = dst_cmd->error_string =
                "inconsistent aliased update";
@@ -1231,10 +1231,10 @@ static int command_singleton_iterator(void *cb_data, unsigned char sha1[20])
        struct command **cmd_list = cb_data;
        struct command *cmd = *cmd_list;
 
-       if (!cmd || is_null_sha1(cmd->new_sha1))
+       if (!cmd || is_null_oid(&cmd->new_oid))
                return -1; /* end of list */
        *cmd_list = NULL; /* this returns only one */
-       hashcpy(sha1, cmd->new_sha1);
+       hashcpy(sha1, cmd->new_oid.hash);
        return 0;
 }
 
@@ -1275,8 +1275,8 @@ static int iterate_receive_command_list(void *cb_data, unsigned char sha1[20])
                if (shallow_update && data->si->shallow_ref[cmd->index])
                        /* to be checked in update_shallow_ref() */
                        continue;
-               if (!is_null_sha1(cmd->new_sha1) && !cmd->skip_update) {
-                       hashcpy(sha1, cmd->new_sha1);
+               if (!is_null_oid(&cmd->new_oid) && !cmd->skip_update) {
+                       hashcpy(sha1, cmd->new_oid.hash);
                        *cmd_list = cmd->next;
                        return 0;
                }
@@ -1303,7 +1303,7 @@ static void reject_updates_to_hidden(struct command *commands)
 
                if (!ref_is_hidden(cmd->ref_name, refname_full.buf))
                        continue;
-               if (is_null_sha1(cmd->new_sha1))
+               if (is_null_oid(&cmd->new_oid))
                        cmd->error_string = "deny deleting a hidden ref";
                else
                        cmd->error_string = "deny updating a hidden ref";
@@ -1486,23 +1486,23 @@ static struct command **queue_command(struct command **tail,
                                      const char *line,
                                      int linelen)
 {
-       unsigned char old_sha1[20], new_sha1[20];
+       struct object_id old_oid, new_oid;
        struct command *cmd;
        const char *refname;
        int reflen;
+       const char *p;
 
-       if (linelen < 83 ||
-           line[40] != ' ' ||
-           line[81] != ' ' ||
-           get_sha1_hex(line, old_sha1) ||
-           get_sha1_hex(line + 41, new_sha1))
+       if (parse_oid_hex(line, &old_oid, &p) ||
+           *p++ != ' ' ||
+           parse_oid_hex(p, &new_oid, &p) ||
+           *p++ != ' ')
                die("protocol error: expected old/new/ref, got '%s'", line);
 
-       refname = line + 82;
-       reflen = linelen - 82;
+       refname = p;
+       reflen = linelen - (p - line);
        FLEX_ALLOC_MEM(cmd, ref_name, refname, reflen);
-       hashcpy(cmd->old_sha1, old_sha1);
-       hashcpy(cmd->new_sha1, new_sha1);
+       oidcpy(&cmd->old_oid, &old_oid);
+       oidcpy(&cmd->new_oid, &new_oid);
        *tail = cmd;
        return &cmd->next;
 }
@@ -1541,12 +1541,12 @@ static struct command *read_head_info(struct sha1_array *shallow)
                if (!line)
                        break;
 
-               if (len == 48 && starts_with(line, "shallow ")) {
-                       unsigned char sha1[20];
-                       if (get_sha1_hex(line + 8, sha1))
+               if (len > 8 && starts_with(line, "shallow ")) {
+                       struct object_id oid;
+                       if (get_oid_hex(line + 8, &oid))
                                die("protocol error: expected shallow sha, got '%s'",
                                    line + 8);
-                       sha1_array_append(shallow, sha1);
+                       sha1_array_append(shallow, oid.hash);
                        continue;
                }
 
@@ -1815,9 +1815,9 @@ static void update_shallow_info(struct command *commands,
        }
 
        for (cmd = commands; cmd; cmd = cmd->next) {
-               if (is_null_sha1(cmd->new_sha1))
+               if (is_null_oid(&cmd->new_oid))
                        continue;
-               sha1_array_append(ref, cmd->new_sha1);
+               sha1_array_append(ref, cmd->new_oid.hash);
                cmd->index = ref->nr - 1;
        }
        si->ref = ref;
@@ -1830,7 +1830,7 @@ static void update_shallow_info(struct command *commands,
        ALLOC_ARRAY(ref_status, ref->nr);
        assign_shallow_commits_to_refs(si, NULL, ref_status);
        for (cmd = commands; cmd; cmd = cmd->next) {
-               if (is_null_sha1(cmd->new_sha1))
+               if (is_null_oid(&cmd->new_oid))
                        continue;
                if (ref_status[cmd->index]) {
                        cmd->error_string = "shallow update not allowed";
@@ -1868,7 +1868,7 @@ static int delete_only(struct command *commands)
 {
        struct command *cmd;
        for (cmd = commands; cmd; cmd = cmd->next) {
-               if (!is_null_sha1(cmd->new_sha1))
+               if (!is_null_oid(&cmd->new_oid))
                        return 0;
        }
        return 1;