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, 48 insertions, 17 deletions

diff --git a/third_party/git/hex.c b/third_party/git/hex.c
index 7850a8879d5e..da51e64929a4 100644
--- a/third_party/git/hex.c
+++ b/third_party/git/hex.c
@@ -47,32 +47,73 @@ int hex_to_bytes(unsigned char *binary, const char *hex, size_t len)
 	return 0;
 }
 
-int get_sha1_hex(const char *hex, unsigned char *sha1)
+static int get_hash_hex_algop(const char *hex, unsigned char *hash,
+			      const struct git_hash_algo *algop)
 {
 	int i;
-	for (i = 0; i < the_hash_algo->rawsz; i++) {
+	for (i = 0; i < algop->rawsz; i++) {
 		int val = hex2chr(hex);
 		if (val < 0)
 			return -1;
-		*sha1++ = val;
+		*hash++ = val;
 		hex += 2;
 	}
 	return 0;
 }
 
+int get_sha1_hex(const char *hex, unsigned char *sha1)
+{
+	return get_hash_hex_algop(hex, sha1, the_hash_algo);
+}
+
+int get_oid_hex_algop(const char *hex, struct object_id *oid,
+		      const struct git_hash_algo *algop)
+{
+	return get_hash_hex_algop(hex, oid->hash, algop);
+}
+
+/*
+ * NOTE: This function relies on hash algorithms being in order from shortest
+ * length to longest length.
+ */
+int get_oid_hex_any(const char *hex, struct object_id *oid)
+{
+	int i;
+	for (i = GIT_HASH_NALGOS - 1; i > 0; i--) {
+		if (!get_hash_hex_algop(hex, oid->hash, &hash_algos[i]))
+			return i;
+	}
+	return GIT_HASH_UNKNOWN;
+}
+
 int get_oid_hex(const char *hex, struct object_id *oid)
 {
-	return get_sha1_hex(hex, oid->hash);
+	return get_oid_hex_algop(hex, oid, the_hash_algo);
 }
 
-int parse_oid_hex(const char *hex, struct object_id *oid, const char **end)
+int parse_oid_hex_algop(const char *hex, struct object_id *oid,
+			const char **end,
+			const struct git_hash_algo *algop)
 {
-	int ret = get_oid_hex(hex, oid);
+	int ret = get_hash_hex_algop(hex, oid->hash, algop);
 	if (!ret)
-		*end = hex + the_hash_algo->hexsz;
+		*end = hex + algop->hexsz;
 	return ret;
 }
 
+int parse_oid_hex_any(const char *hex, struct object_id *oid, const char **end)
+{
+	int ret = get_oid_hex_any(hex, oid);
+	if (ret)
+		*end = hex + hash_algos[ret].hexsz;
+	return ret;
+}
+
+int parse_oid_hex(const char *hex, struct object_id *oid, const char **end)
+{
+	return parse_oid_hex_algop(hex, oid, end, the_hash_algo);
+}
+
 char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash,
 			  const struct git_hash_algo *algop)
 {
@@ -90,11 +131,6 @@ char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash,
 	return buffer;
 }
 
-char *sha1_to_hex_r(char *buffer, const unsigned char *sha1)
-{
-	return hash_to_hex_algop_r(buffer, sha1, &hash_algos[GIT_HASH_SHA1]);
-}
-
 char *oid_to_hex_r(char *buffer, const struct object_id *oid)
 {
 	return hash_to_hex_algop_r(buffer, oid->hash, the_hash_algo);
@@ -108,11 +144,6 @@ char *hash_to_hex_algop(const unsigned char *hash, const struct git_hash_algo *a
 	return hash_to_hex_algop_r(hexbuffer[bufno], hash, algop);
 }
 
-char *sha1_to_hex(const unsigned char *sha1)
-{
-	return hash_to_hex_algop(sha1, &hash_algos[GIT_HASH_SHA1]);
-}
-
 char *hash_to_hex(const unsigned char *hash)
 {
 	return hash_to_hex_algop(hash, the_hash_algo);