wrapper.c: add and use fopen_or_warn()
[gitweb.git] / refs.c
diff --git a/refs.c b/refs.c
index a3d5f42e37345096628ab83fee629f22df1bb7b5..df75f8e0d695fc235c1a2497069a9b916a4a04e8 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -5,6 +5,7 @@
 #include "cache.h"
 #include "hashmap.h"
 #include "lockfile.h"
+#include "iterator.h"
 #include "refs.h"
 #include "refs/refs-internal.h"
 #include "object.h"
@@ -1238,6 +1239,18 @@ int head_ref(each_ref_fn fn, void *cb_data)
        return head_ref_submodule(NULL, fn, cb_data);
 }
 
+struct ref_iterator *refs_ref_iterator_begin(
+               struct ref_store *refs,
+               const char *prefix, int trim, int flags)
+{
+       struct ref_iterator *iter;
+
+       iter = refs->be->iterator_begin(refs, prefix, flags);
+       iter = prefix_ref_iterator_begin(iter, prefix, trim);
+
+       return iter;
+}
+
 /*
  * Call fn for each reference in the specified submodule for which the
  * refname begins with prefix. If trim is non-zero, then trim that
@@ -1255,8 +1268,7 @@ static int do_for_each_ref(struct ref_store *refs, const char *prefix,
        if (!refs)
                return 0;
 
-       iter = refs->be->iterator_begin(refs, prefix, flags);
-       iter = prefix_ref_iterator_begin(iter, prefix, trim);
+       iter = refs_ref_iterator_begin(refs, prefix, trim, flags);
 
        return do_for_each_ref_iterator(iter, fn, cb_data);
 }
@@ -1334,6 +1346,13 @@ int for_each_rawref(each_ref_fn fn, void *cb_data)
        return refs_for_each_rawref(get_main_ref_store(), fn, cb_data);
 }
 
+int refs_read_raw_ref(struct ref_store *ref_store,
+                     const char *refname, unsigned char *sha1,
+                     struct strbuf *referent, unsigned int *type)
+{
+       return ref_store->be->read_raw_ref(ref_store, refname, sha1, referent, type);
+}
+
 /* This function needs to return a meaningful errno on failure */
 const char *refs_resolve_ref_unsafe(struct ref_store *refs,
                                    const char *refname,
@@ -1370,8 +1389,8 @@ const char *refs_resolve_ref_unsafe(struct ref_store *refs,
        for (symref_count = 0; symref_count < SYMREF_MAXDEPTH; symref_count++) {
                unsigned int read_flags = 0;
 
-               if (refs->be->read_raw_ref(refs, refname,
-                                          sha1, &sb_refname, &read_flags)) {
+               if (refs_read_raw_ref(refs, refname,
+                                     sha1, &sb_refname, &read_flags)) {
                        *flags |= read_flags;
                        if (errno != ENOENT || (resolve_flags & RESOLVE_REF_READING))
                                return NULL;
@@ -1654,11 +1673,91 @@ int ref_transaction_commit(struct ref_transaction *transaction,
 
 int refs_verify_refname_available(struct ref_store *refs,
                                  const char *refname,
-                                 const struct string_list *extra,
+                                 const struct string_list *extras,
                                  const struct string_list *skip,
                                  struct strbuf *err)
 {
-       return refs->be->verify_refname_available(refs, refname, extra, skip, err);
+       const char *slash;
+       const char *extra_refname;
+       struct strbuf dirname = STRBUF_INIT;
+       struct strbuf referent = STRBUF_INIT;
+       struct object_id oid;
+       unsigned int type;
+       struct ref_iterator *iter;
+       int ok;
+       int ret = -1;
+
+       /*
+        * For the sake of comments in this function, suppose that
+        * refname is "refs/foo/bar".
+        */
+
+       assert(err);
+
+       strbuf_grow(&dirname, strlen(refname) + 1);
+       for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
+               /* Expand dirname to the new prefix, not including the trailing slash: */
+               strbuf_add(&dirname, refname + dirname.len, slash - refname - dirname.len);
+
+               /*
+                * We are still at a leading dir of the refname (e.g.,
+                * "refs/foo"; if there is a reference with that name,
+                * it is a conflict, *unless* it is in skip.
+                */
+               if (skip && string_list_has_string(skip, dirname.buf))
+                       continue;
+
+               if (!refs_read_raw_ref(refs, dirname.buf, oid.hash, &referent, &type)) {
+                       strbuf_addf(err, "'%s' exists; cannot create '%s'",
+                                   dirname.buf, refname);
+                       goto cleanup;
+               }
+
+               if (extras && string_list_has_string(extras, dirname.buf)) {
+                       strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
+                                   refname, dirname.buf);
+                       goto cleanup;
+               }
+       }
+
+       /*
+        * We are at the leaf of our refname (e.g., "refs/foo/bar").
+        * There is no point in searching for a reference with that
+        * name, because a refname isn't considered to conflict with
+        * itself. But we still need to check for references whose
+        * names are in the "refs/foo/bar/" namespace, because they
+        * *do* conflict.
+        */
+       strbuf_addstr(&dirname, refname + dirname.len);
+       strbuf_addch(&dirname, '/');
+
+       iter = refs_ref_iterator_begin(refs, dirname.buf, 0,
+                                      DO_FOR_EACH_INCLUDE_BROKEN);
+       while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
+               if (skip &&
+                   string_list_has_string(skip, iter->refname))
+                       continue;
+
+               strbuf_addf(err, "'%s' exists; cannot create '%s'",
+                           iter->refname, refname);
+               ref_iterator_abort(iter);
+               goto cleanup;
+       }
+
+       if (ok != ITER_DONE)
+               die("BUG: error while iterating over references");
+
+       extra_refname = find_descendant_ref(dirname.buf, extras, skip);
+       if (extra_refname)
+               strbuf_addf(err, "cannot process '%s' and '%s' at the same time",
+                           refname, extra_refname);
+       else
+               ret = 0;
+
+cleanup:
+       strbuf_release(&referent);
+       strbuf_release(&dirname);
+       return ret;
 }
 
 int refs_for_each_reflog(struct ref_store *refs, each_ref_fn fn, void *cb_data)