Demonstrate breakage: checkout overwrites untracked symlink with directory

diff --git a/sha1_name.c b/sha1_name.c
index 207405688bb919363c0fdde31083f2e57d26e050..709ff2eee64cf106191ad274bede82a95d00e2a3 100644 (file)
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -7,6 +7,8 @@
 #include "refs.h"
 #include "remote.h"
 
+static int get_sha1_oneline(const char *, unsigned char *, struct commit_list *);
+
 static int find_short_object_filename(int len, const char *name, unsigned char *sha1)
 {
        struct alternate_object_database *alt;
@@ -206,7 +208,9 @@ const char *find_unique_abbrev(const unsigned char *sha1, int len)
                if (exists
                    ? !status
                    : status == SHORT_NAME_NOT_FOUND) {
-                       hex[len] = 0;
+                       int cut_at = len + unique_abbrev_extra_length;
+                       cut_at = (cut_at < 40) ? cut_at : 40;
+                       hex[cut_at] = 0;
                        return hex;
                }
                len++;
@@ -560,6 +564,8 @@ static int peel_onion(const char *name, int len, unsigned char *sha1)
                expected_type = OBJ_BLOB;
        else if (sp[0] == '}')
                expected_type = OBJ_NONE;
+       else if (sp[0] == '/')
+               expected_type = OBJ_COMMIT;
        else
                return -1;
 
@@ -574,19 +580,37 @@ static int peel_onion(const char *name, int len, unsigned char *sha1)
                if (!o || (!o->parsed && !parse_object(o->sha1)))
                        return -1;
                hashcpy(sha1, o->sha1);
+               return 0;
        }
-       else {
+
+       /*
+        * At this point, the syntax look correct, so
+        * if we do not get the needed object, we should
+        * barf.
+        */
+       o = peel_to_type(name, len, o, expected_type);
+       if (!o)
+               return -1;
+
+       hashcpy(sha1, o->sha1);
+       if (sp[0] == '/') {
+               /* "$commit^{/foo}" */
+               char *prefix;
+               int ret;
+               struct commit_list *list = NULL;
+
                /*
-                * At this point, the syntax look correct, so
-                * if we do not get the needed object, we should
-                * barf.
+                * $commit^{/}. Some regex implementation may reject.
+                * We don't need regex anyway. '' pattern always matches.
                 */
-               o = peel_to_type(name, len, o, expected_type);
-               if (o) {
-                       hashcpy(sha1, o->sha1);
+               if (sp[1] == '}')
                        return 0;
-               }
-               return -1;
+
+               prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
+               commit_list_insert((struct commit *)o, &list);
+               ret = get_sha1_oneline(prefix, sha1, list);
+               free(prefix);
+               return ret;
        }
        return 0;
 }
@@ -683,16 +707,15 @@ static int handle_one_ref(const char *path,
        }
        if (object->type != OBJ_COMMIT)
                return 0;
-       insert_by_date((struct commit *)object, list);
-       object->flags |= ONELINE_SEEN;
+       commit_list_insert_by_date((struct commit *)object, list);
        return 0;
 }
 
-static int get_sha1_oneline(const char *prefix, unsigned char *sha1)
+static int get_sha1_oneline(const char *prefix, unsigned char *sha1,
+                           struct commit_list *list)
 {
-       struct commit_list *list = NULL, *backup = NULL, *l;
-       int retval = -1;
-       char *temp_commit_buffer = NULL;
+       struct commit_list *backup = NULL, *l;
+       int found = 0;
        regex_t regex;
 
        if (prefix[0] == '!') {
@@ -704,41 +727,45 @@ static int get_sha1_oneline(const char *prefix, unsigned char *sha1)
        if (regcomp(&regex, prefix, REG_EXTENDED))
                die("Invalid search pattern: %s", prefix);
 
-       for_each_ref(handle_one_ref, &list);
-       for (l = list; l; l = l->next)
+       for (l = list; l; l = l->next) {
+               l->item->object.flags |= ONELINE_SEEN;
                commit_list_insert(l->item, &backup);
+       }
        while (list) {
-               char *p;
+               char *p, *to_free = NULL;
                struct commit *commit;
                enum object_type type;
                unsigned long size;
+               int matches;
 
                commit = pop_most_recent_commit(&list, ONELINE_SEEN);
                if (!parse_object(commit->object.sha1))
                        continue;
-               free(temp_commit_buffer);
                if (commit->buffer)
                        p = commit->buffer;
                else {
                        p = read_sha1_file(commit->object.sha1, &type, &size);
                        if (!p)
                                continue;
-                       temp_commit_buffer = p;
+                       to_free = p;
                }
-               if (!(p = strstr(p, "\n\n")))
-                       continue;
-               if (!regexec(&regex, p + 2, 0, NULL, 0)) {
+
+               p = strstr(p, "\n\n");
+               matches = p && !regexec(&regex, p + 2, 0, NULL, 0);
+               free(to_free);
+
+               if (matches) {
                        hashcpy(sha1, commit->object.sha1);
-                       retval = 0;
+                       found = 1;
                        break;
                }
        }
        regfree(&regex);
-       free(temp_commit_buffer);
        free_commit_list(list);
        for (l = backup; l; l = l->next)
                clear_commit_marks(l->item, ONELINE_SEEN);
-       return retval;
+       free_commit_list(backup);
+       return found ? 0 : -1;
 }
 
 struct grab_nth_branch_switch_cbdata {
@@ -934,6 +961,24 @@ int interpret_branch_name(const char *name, struct strbuf *buf)
        return len;
 }
 
+int strbuf_branchname(struct strbuf *sb, const char *name)
+{
+       int len = strlen(name);
+       if (interpret_branch_name(name, sb) == len)
+               return 0;
+       strbuf_add(sb, name, len);
+       return len;
+}
+
+int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
+{
+       strbuf_branchname(sb, name);
+       if (name[0] == '-')
+               return CHECK_REF_FORMAT_ERROR;
+       strbuf_splice(sb, 0, 0, "refs/heads/", 11);
+       return check_ref_format(sb->buf);
+}
+
 /*
  * This is like "get_sha1_basic()", except it allows "sha1 expressions",
  * notably "xyz^" for "parent of xyz"
@@ -1087,8 +1132,11 @@ int get_sha1_with_context_1(const char *name, unsigned char *sha1,
                struct cache_entry *ce;
                char *new_path = NULL;
                int pos;
-               if (namelen > 2 && name[1] == '/')
-                       return get_sha1_oneline(name + 2, sha1);
+               if (namelen > 2 && name[1] == '/') {
+                       struct commit_list *list = NULL;
+                       for_each_ref(handle_one_ref, &list);
+                       return get_sha1_oneline(name + 2, sha1, list);
+               }
                if (namelen < 3 ||
                    name[2] != ':' ||
                    name[1] < '0' || '3' < name[1])
@@ -1121,6 +1169,7 @@ int get_sha1_with_context_1(const char *name, unsigned char *sha1,
                                break;
                        if (ce_stage(ce) == stage) {
                                hashcpy(sha1, ce->sha1);
+                               oc->mode = ce->ce_mode;
                                free(new_path);
                                return 0;
                        }