refs: expose 'for_each_fullref_in_prefixes'

This function was used in the ref-filter.c code to find the longest
common prefix of among a set of refspecs, and then to iterate all of the
references that descend from that prefix.

A future patch will want to use that same code from ls-refs.c, so
prepare by exposing and moving it to refs.c. Since there is nothing
specific to the ref-filter code here (other than that it was previously
the only caller of this function), this really belongs in the more
generic refs.h header.

The code moved in this patch is identical before and after, with the one
exception of renaming some arguments to be consistent with other
functions exposed in refs.h.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/ref-filter.c b/ref-filter.c
index aa260bfd0995564e085f69b5b1c7ecaf4b49f359..f918f0015167ed6fc03f07c4f179365653c7e072 100644 (file)
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -1929,64 +1929,6 @@ static int filter_pattern_match(struct ref_filter *filter, const char *refname)
        return match_pattern(filter, refname);
 }
 
-static int qsort_strcmp(const void *va, const void *vb)
-{
-       const char *a = *(const char **)va;
-       const char *b = *(const char **)vb;
-
-       return strcmp(a, b);
-}
-
-static void find_longest_prefixes_1(struct string_list *out,
-                                 struct strbuf *prefix,
-                                 const char **patterns, size_t nr)
-{
-       size_t i;
-
-       for (i = 0; i < nr; i++) {
-               char c = patterns[i][prefix->len];
-               if (!c || is_glob_special(c)) {
-                       string_list_append(out, prefix->buf);
-                       return;
-               }
-       }
-
-       i = 0;
-       while (i < nr) {
-               size_t end;
-
-               /*
-               * Set "end" to the index of the element _after_ the last one
-               * in our group.
-               */
-               for (end = i + 1; end < nr; end++) {
-                       if (patterns[i][prefix->len] != patterns[end][prefix->len])
-                               break;
-               }
-
-               strbuf_addch(prefix, patterns[i][prefix->len]);
-               find_longest_prefixes_1(out, prefix, patterns + i, end - i);
-               strbuf_setlen(prefix, prefix->len - 1);
-
-               i = end;
-       }
-}
-
-static void find_longest_prefixes(struct string_list *out,
-                                 const char **patterns)
-{
-       struct strvec sorted = STRVEC_INIT;
-       struct strbuf prefix = STRBUF_INIT;
-
-       strvec_pushv(&sorted, patterns);
-       QSORT(sorted.v, sorted.nr, qsort_strcmp);
-
-       find_longest_prefixes_1(out, &prefix, sorted.v, sorted.nr);
-
-       strvec_clear(&sorted);
-       strbuf_release(&prefix);
-}
-
 /*
  * This is the same as for_each_fullref_in(), but it tries to iterate
  * only over the patterns we'll care about. Note that it _doesn't_ do a full
@@ -1997,10 +1939,6 @@ static int for_each_fullref_in_pattern(struct ref_filter *filter,
                                       void *cb_data,
                                       int broken)
 {
-       struct string_list prefixes = STRING_LIST_INIT_DUP;
-       struct string_list_item *prefix;
-       int ret;
-
        if (!filter->match_as_path) {
                /*
                 * in this case, the patterns are applied after
@@ -2024,16 +1962,8 @@ static int for_each_fullref_in_pattern(struct ref_filter *filter,
                return for_each_fullref_in("", cb, cb_data, broken);
        }
 
-       find_longest_prefixes(&prefixes, filter->name_patterns);
-
-       for_each_string_list_item(prefix, &prefixes) {
-               ret = for_each_fullref_in(prefix->string, cb, cb_data, broken);
-               if (ret)
-                       break;
-       }
-
-       string_list_clear(&prefixes, 0);
-       return ret;
+       return for_each_fullref_in_prefixes(NULL, filter->name_patterns,
+                                           cb, cb_data, broken);
 }
 
 /*

diff --git a/refs.c b/refs.c
index 13dc2c3291b398aae7c9797155363922def64eff..e0f439b7fd6b22321ffba6aaff5dfa4462932905 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -1546,6 +1546,93 @@ int for_each_rawref(each_ref_fn fn, void *cb_data)
        return refs_for_each_rawref(get_main_ref_store(the_repository), fn, cb_data);
 }
 
+static int qsort_strcmp(const void *va, const void *vb)
+{
+       const char *a = *(const char **)va;
+       const char *b = *(const char **)vb;
+
+       return strcmp(a, b);
+}
+
+static void find_longest_prefixes_1(struct string_list *out,
+                                 struct strbuf *prefix,
+                                 const char **patterns, size_t nr)
+{
+       size_t i;
+
+       for (i = 0; i < nr; i++) {
+               char c = patterns[i][prefix->len];
+               if (!c || is_glob_special(c)) {
+                       string_list_append(out, prefix->buf);
+                       return;
+               }
+       }
+
+       i = 0;
+       while (i < nr) {
+               size_t end;
+
+               /*
+               * Set "end" to the index of the element _after_ the last one
+               * in our group.
+               */
+               for (end = i + 1; end < nr; end++) {
+                       if (patterns[i][prefix->len] != patterns[end][prefix->len])
+                               break;
+               }
+
+               strbuf_addch(prefix, patterns[i][prefix->len]);
+               find_longest_prefixes_1(out, prefix, patterns + i, end - i);
+               strbuf_setlen(prefix, prefix->len - 1);
+
+               i = end;
+       }
+}
+
+static void find_longest_prefixes(struct string_list *out,
+                                 const char **patterns)
+{
+       struct strvec sorted = STRVEC_INIT;
+       struct strbuf prefix = STRBUF_INIT;
+
+       strvec_pushv(&sorted, patterns);
+       QSORT(sorted.v, sorted.nr, qsort_strcmp);
+
+       find_longest_prefixes_1(out, &prefix, sorted.v, sorted.nr);
+
+       strvec_clear(&sorted);
+       strbuf_release(&prefix);
+}
+
+int for_each_fullref_in_prefixes(const char *namespace,
+                                const char **patterns,
+                                each_ref_fn fn, void *cb_data,
+                                unsigned int broken)
+{
+       struct string_list prefixes = STRING_LIST_INIT_DUP;
+       struct string_list_item *prefix;
+       struct strbuf buf = STRBUF_INIT;
+       int ret = 0, namespace_len;
+
+       find_longest_prefixes(&prefixes, patterns);
+
+       if (namespace)
+               strbuf_addstr(&buf, namespace);
+       namespace_len = buf.len;
+
+       for_each_string_list_item(prefix, &prefixes) {
+               strbuf_addstr(&buf, prefix->string);
+               ret = for_each_fullref_in(buf.buf, fn, cb_data, broken);
+               if (ret)
+                       break;
+               strbuf_setlen(&buf, namespace_len);
+       }
+
+       string_list_clear(&prefixes, 0);
+       strbuf_release(&buf);
+       return ret;
+}
+
 static int refs_read_special_head(struct ref_store *ref_store,
                                  const char *refname, struct object_id *oid,
                                  struct strbuf *referent, unsigned int *type)

diff --git a/refs.h b/refs.h
index ff05d2e9fe27cfc3486c42a1cfcf99941eaf9774..c5fd35487da0af5cfa182f08b1951ac2da77b17c 100644 (file)
--- a/refs.h
+++ b/refs.h
@@ -347,6 +347,15 @@ int refs_for_each_fullref_in(struct ref_store *refs, const char *prefix,
 int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data,
                        unsigned int broken);
 
+/**
+ * iterate all refs in "patterns" by partitioning patterns into disjoint sets
+ * and iterating the longest-common prefix of each set.
+ *
+ * callers should be prepared to ignore references that they did not ask for.
+ */
+int for_each_fullref_in_prefixes(const char *namespace, const char **patterns,
+                                each_ref_fn fn, void *cb_data,
+                                unsigned int broken);
 /**
  * iterate refs from the respective area.
  */