merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 23 insertions, 2 deletions

diff --git a/third_party/git/refspec.h b/third_party/git/refspec.h
index 9b6e64a824..9551832399 100644
--- a/third_party/git/refspec.h
+++ b/third_party/git/refspec.h
@@ -4,11 +4,26 @@
 #define TAG_REFSPEC "refs/tags/*:refs/tags/*"
 extern const struct refspec_item *tag_refspec;
 
+/**
+ * A struct refspec_item holds the parsed interpretation of a refspec.  If it
+ * will force updates (starts with a '+'), force is true.  If it is a pattern
+ * (sides end with '*') pattern is true.  If it is a negative refspec, (starts
+ * with '^'), negative is true.  src and dest are the two sides (including '*'
+ * characters if present); if there is only one side, it is src, and dst is
+ * NULL; if sides exist but are empty (i.e., the refspec either starts or ends
+ * with ':'), the corresponding side is "".
+ *
+ * remote_find_tracking(), given a remote and a struct refspec_item with either src
+ * or dst filled out, will fill out the other such that the result is in the
+ * "fetch" specification for the remote (note that this evaluates patterns and
+ * returns a single result).
+ */
 struct refspec_item {
 	unsigned force : 1;
 	unsigned pattern : 1;
 	unsigned matching : 1;
 	unsigned exact_sha1 : 1;
+	unsigned negative : 1;
 
 	char *src;
 	char *dst;
@@ -20,6 +35,10 @@ struct refspec_item {
 #define REFSPEC_INIT_FETCH { .fetch = REFSPEC_FETCH }
 #define REFSPEC_INIT_PUSH { .fetch = REFSPEC_PUSH }
 
+/**
+ * An array of strings can be parsed into a struct refspec using
+ * parse_fetch_refspec() or parse_push_refspec().
+ */
 struct refspec {
 	struct refspec_item *items;
 	int alloc;
@@ -39,17 +58,19 @@ void refspec_item_init_or_die(struct refspec_item *item, const char *refspec,
 void refspec_item_clear(struct refspec_item *item);
 void refspec_init(struct refspec *rs, int fetch);
 void refspec_append(struct refspec *rs, const char *refspec);
+__attribute__((format (printf,2,3)))
+void refspec_appendf(struct refspec *rs, const char *fmt, ...);
 void refspec_appendn(struct refspec *rs, const char **refspecs, int nr);
 void refspec_clear(struct refspec *rs);
 
 int valid_fetch_refspec(const char *refspec);
 
-struct argv_array;
+struct strvec;
 /*
  * Determine what <prefix> values to pass to the peer in ref-prefix lines
  * (see Documentation/technical/protocol-v2.txt).
  */
 void refspec_ref_prefixes(const struct refspec *rs,
-			  struct argv_array *ref_prefixes);
+			  struct strvec *ref_prefixes);
 
 #endif /* REFSPEC_H */