Squashed 'third_party/git/' content from commit cb71568594

git-subtree-dir: third_party/git
git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7

1 files changed, 232 insertions, 0 deletions

diff --git a/refspec.c b/refspec.c
new file mode 100644
index 0000000000..9a9bf21934
--- /dev/null
+++ b/refspec.c
@@ -0,0 +1,232 @@
+#include "cache.h"
+#include "argv-array.h"
+#include "refs.h"
+#include "refspec.h"
+
+static struct refspec_item s_tag_refspec = {
+	0,
+	1,
+	0,
+	0,
+	"refs/tags/*",
+	"refs/tags/*"
+};
+
+/* See TAG_REFSPEC for the string version */
+const struct refspec_item *tag_refspec = &s_tag_refspec;
+
+/*
+ * Parses the provided refspec 'refspec' and populates the refspec_item 'item'.
+ * Returns 1 if successful and 0 if the refspec is invalid.
+ */
+static int parse_refspec(struct refspec_item *item, const char *refspec, int fetch)
+{
+	size_t llen;
+	int is_glob;
+	const char *lhs, *rhs;
+	int flags;
+
+	is_glob = 0;
+
+	lhs = refspec;
+	if (*lhs == '+') {
+		item->force = 1;
+		lhs++;
+	}
+
+	rhs = strrchr(lhs, ':');
+
+	/*
+	 * Before going on, special case ":" (or "+:") as a refspec
+	 * for pushing matching refs.
+	 */
+	if (!fetch && rhs == lhs && rhs[1] == '\0') {
+		item->matching = 1;
+		return 1;
+	}
+
+	if (rhs) {
+		size_t rlen = strlen(++rhs);
+		is_glob = (1 <= rlen && strchr(rhs, '*'));
+		item->dst = xstrndup(rhs, rlen);
+	} else {
+		item->dst = NULL;
+	}
+
+	llen = (rhs ? (rhs - lhs - 1) : strlen(lhs));
+	if (1 <= llen && memchr(lhs, '*', llen)) {
+		if ((rhs && !is_glob) || (!rhs && fetch))
+			return 0;
+		is_glob = 1;
+	} else if (rhs && is_glob) {
+		return 0;
+	}
+
+	item->pattern = is_glob;
+	item->src = xstrndup(lhs, llen);
+	flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
+
+	if (fetch) {
+		struct object_id unused;
+
+		/* LHS */
+		if (!*item->src)
+			; /* empty is ok; it means "HEAD" */
+		else if (llen == the_hash_algo->hexsz && !get_oid_hex(item->src, &unused))
+			item->exact_sha1 = 1; /* ok */
+		else if (!check_refname_format(item->src, flags))
+			; /* valid looking ref is ok */
+		else
+			return 0;
+		/* RHS */
+		if (!item->dst)
+			; /* missing is ok; it is the same as empty */
+		else if (!*item->dst)
+			; /* empty is ok; it means "do not store" */
+		else if (!check_refname_format(item->dst, flags))
+			; /* valid looking ref is ok */
+		else
+			return 0;
+	} else {
+		/*
+		 * LHS
+		 * - empty is allowed; it means delete.
+		 * - when wildcarded, it must be a valid looking ref.
+		 * - otherwise, it must be an extended SHA-1, but
+		 *   there is no existing way to validate this.
+		 */
+		if (!*item->src)
+			; /* empty is ok */
+		else if (is_glob) {
+			if (check_refname_format(item->src, flags))
+				return 0;
+		}
+		else
+			; /* anything goes, for now */
+		/*
+		 * RHS
+		 * - missing is allowed, but LHS then must be a
+		 *   valid looking ref.
+		 * - empty is not allowed.
+		 * - otherwise it must be a valid looking ref.
+		 */
+		if (!item->dst) {
+			if (check_refname_format(item->src, flags))
+				return 0;
+		} else if (!*item->dst) {
+			return 0;
+		} else {
+			if (check_refname_format(item->dst, flags))
+				return 0;
+		}
+	}
+
+	return 1;
+}
+
+int refspec_item_init(struct refspec_item *item, const char *refspec, int fetch)
+{
+	memset(item, 0, sizeof(*item));
+	return parse_refspec(item, refspec, fetch);
+}
+
+void refspec_item_init_or_die(struct refspec_item *item, const char *refspec,
+			      int fetch)
+{
+	if (!refspec_item_init(item, refspec, fetch))
+		die(_("invalid refspec '%s'"), refspec);
+}
+
+void refspec_item_clear(struct refspec_item *item)
+{
+	FREE_AND_NULL(item->src);
+	FREE_AND_NULL(item->dst);
+	item->force = 0;
+	item->pattern = 0;
+	item->matching = 0;
+	item->exact_sha1 = 0;
+}
+
+void refspec_init(struct refspec *rs, int fetch)
+{
+	memset(rs, 0, sizeof(*rs));
+	rs->fetch = fetch;
+}
+
+void refspec_append(struct refspec *rs, const char *refspec)
+{
+	struct refspec_item item;
+
+	refspec_item_init_or_die(&item, refspec, rs->fetch);
+
+	ALLOC_GROW(rs->items, rs->nr + 1, rs->alloc);
+	rs->items[rs->nr++] = item;
+
+	ALLOC_GROW(rs->raw, rs->raw_nr + 1, rs->raw_alloc);
+	rs->raw[rs->raw_nr++] = xstrdup(refspec);
+}
+
+void refspec_appendn(struct refspec *rs, const char **refspecs, int nr)
+{
+	int i;
+	for (i = 0; i < nr; i++)
+		refspec_append(rs, refspecs[i]);
+}
+
+void refspec_clear(struct refspec *rs)
+{
+	int i;
+
+	for (i = 0; i < rs->nr; i++)
+		refspec_item_clear(&rs->items[i]);
+
+	FREE_AND_NULL(rs->items);
+	rs->alloc = 0;
+	rs->nr = 0;
+
+	for (i = 0; i < rs->raw_nr; i++)
+		free((char *)rs->raw[i]);
+	FREE_AND_NULL(rs->raw);
+	rs->raw_alloc = 0;
+	rs->raw_nr = 0;
+
+	rs->fetch = 0;
+}
+
+int valid_fetch_refspec(const char *fetch_refspec_str)
+{
+	struct refspec_item refspec;
+	int ret = refspec_item_init(&refspec, fetch_refspec_str, REFSPEC_FETCH);
+	refspec_item_clear(&refspec);
+	return ret;
+}
+
+void refspec_ref_prefixes(const struct refspec *rs,
+			  struct argv_array *ref_prefixes)
+{
+	int i;
+	for (i = 0; i < rs->nr; i++) {
+		const struct refspec_item *item = &rs->items[i];
+		const char *prefix = NULL;
+
+		if (item->exact_sha1)
+			continue;
+		if (rs->fetch == REFSPEC_FETCH)
+			prefix = item->src;
+		else if (item->dst)
+			prefix = item->dst;
+		else if (item->src && !item->exact_sha1)
+			prefix = item->src;
+
+		if (prefix) {
+			if (item->pattern) {
+				const char *glob = strchr(prefix, '*');
+				argv_array_pushf(ref_prefixes, "%.*s",
+						 (int)(glob - prefix),
+						 prefix);
+			} else {
+				expand_ref_prefix(ref_prefixes, prefix);
+			}
+		}
+	}
+}