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[PATCH v2 26/42] sha1-file: add functions for hex empty tree and blob OIDs

From
brian m. carlson <sandals@crustytoothpaste.net>
Date
May 2, 2018, 00:25 UTC
Message-ID
<20180502002610.915892-27-sandals@crustytoothpaste.net>
In-Reply-To
<20180502002610.915892-1-sandals@crustytoothpaste.net>

Oftentimes, we'll want to refer to an empty tree or empty blob by its hex name without having to call oid_to_hex or explicitly refer to the_hash_algo. Add helper functions that format these values into static buffers and return them for easy use.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
---
 cache.h     |  3 +++
 sha1-file.c | 12 ++++++++++++
 2 files changed, 15 insertions(+)
diff --git a/cache.h b/cache.h
index 37d081b8e4..7115770fa6 100644
--- a/cache.h
+++ b/cache.h
@@ -1049,6 +1049,9 @@ static inline int is_empty_tree_oid(const struct object_id *oid)
 	return !oidcmp(oid, the_hash_algo->empty_tree);
 }
 
+const char *empty_tree_oid_hex(void);
+const char *empty_blob_oid_hex(void);
+
 /* set default permissions by passing mode arguments to open(2) */
 int git_mkstemps_mode(char *pattern, int suffix_len, int mode);
 int git_mkstemp_mode(char *pattern, int mode);
diff --git a/sha1-file.c b/sha1-file.c
index 4328c61285..11598b43eb 100644
--- a/sha1-file.c
+++ b/sha1-file.c
@@ -100,6 +100,18 @@ const struct git_hash_algo hash_algos[GIT_HASH_NALGOS] = {
 	},
 };
 
+const char *empty_tree_oid_hex(void)
+{
+	static char buf[GIT_MAX_HEXSZ + 1];
+	return oid_to_hex_r(buf, the_hash_algo->empty_tree);
+}
+
+const char *empty_blob_oid_hex(void)
+{
+	static char buf[GIT_MAX_HEXSZ + 1];
+	return oid_to_hex_r(buf, the_hash_algo->empty_blob);
+}
+
 /*
  * This is meant to hold a *small* number of objects that you would
  * want read_sha1_file() to be able to return, but yet you do not want
Previous: brian m. carlsonNext: brian m. carlson
Message 25 of 45 in “object_id part 13”
  1. 00/42 object_id part 13brian m. carlson, May 2, 2018
  2. 01/42 cache: add a function to read an object ID from a bufferbrian m. carlson, May 2, 2018
  3. 02/42 server-info: remove unused members from struct pack_infobrian m. carlson, May 2, 2018
  4. 06/42 sha1-file: convert freshen functions to object_idbrian m. carlson, May 2, 2018
  5. 07/42 packfile: convert find_pack_entry to object_idbrian m. carlson, May 2, 2018
  6. 11/42 tree-walk: avoid hard-coded 20 constantbrian m. carlson, May 2, 2018
  7. 05/42 packfile: convert has_sha1_pack to object_idbrian m. carlson, May 2, 2018
  8. 13/42 fsck: convert static functions to struct object_idbrian m. carlson, May 2, 2018
  9. 17/42 pack-redundant: convert linked lists to use struct object_idbrian m. carlson, May 2, 2018
  10. 15/42 split-index: convert struct split_index to object_idbrian m. carlson, May 2, 2018
  11. 14/42 submodule-config: convert structures to object_idbrian m. carlson, May 2, 2018
  12. 18/42 index-pack: abstract away hash function constantbrian m. carlson, May 2, 2018
  13. 12/42 tree-walk: convert get_tree_entry_follow_symlinks to object_idbrian m. carlson, May 2, 2018
  14. 10/42 pack-redundant: abstract away hash algorithmbrian m. carlson, May 2, 2018
  15. 09/42 pack-objects: abstract away hash algorithmbrian m. carlson, May 2, 2018
  16. 27/42 builtin/am: convert uses of EMPTY_TREE_SHA1_BIN to the_hash_algobrian m. carlson, May 2, 2018
  17. 28/42 builtin/merge: switch tree functions to use object_idbrian m. carlson, May 2, 2018
  18. 25/42 builtin/receive-pack: avoid hard-coded constants for push certsbrian m. carlson, May 2, 2018
  19. 35/42 sha1_file: convert cached object code to struct object_idbrian m. carlson, May 2, 2018
  20. 38/42 dir: use the_hash_algo for empty blob object IDbrian m. carlson, May 2, 2018
  21. 37/42 sequencer: use the_hash_algo for empty tree object IDbrian m. carlson, May 2, 2018
  22. 36/42 cache-tree: use is_empty_tree_oidbrian m. carlson, May 2, 2018
  23. 41/42 add--interactive: compute the empty tree valuebrian m. carlson, May 2, 2018
  24. 39/42 sha1_file: only expose empty object constants through git_hash_algobrian m. carlson, May 2, 2018
  25. 26/42 sha1-file: add functions for hex empty tree and blob OIDsbrian m. carlson, May 2, 2018
  26. 42/42 merge-one-file: compute empty blob object IDbrian m. carlson, May 2, 2018
  27. 40/42 Update shell scripts to compute empty tree object IDbrian m. carlson, May 2, 2018
  28. 34/42 builtin/reset: convert use of EMPTY_TREE_SHA1_BINbrian m. carlson, May 2, 2018
  29. 33/42 builtin/receive-pack: convert one use of EMPTY_TREE_SHA1_HEXbrian m. carlson, May 2, 2018
  30. 32/42 wt-status: convert two uses of EMPTY_TREE_SHA1_HEXbrian m. carlson, May 2, 2018
  31. 31/42 submodule: convert several uses of EMPTY_TREE_SHA1_HEXbrian m. carlson, May 2, 2018
  32. 30/42 sequencer: convert one use of EMPTY_TREE_SHA1_HEXbrian m. carlson, May 2, 2018
  33. 29/42 merge: convert empty tree constant to the_hash_algobrian m. carlson, May 2, 2018
  34. 23/42 upload-pack: replace use of several hard-coded constantsbrian m. carlson, May 2, 2018
  35. 22/42 revision: replace use of hard-coded constantsbrian m. carlson, May 2, 2018
  36. 24/42 diff: specify abbreviation size in terms of the_hash_algobrian m. carlson, May 2, 2018
  37. 16/42 Update struct index_state to use struct object_idbrian m. carlson, May 2, 2018
  38. 21/42 http: eliminate hard-coded constantsbrian m. carlson, May 2, 2018
  39. 20/42 dir: convert struct untracked_cache_dir to object_idbrian m. carlson, May 2, 2018
  40. 19/42 commit: convert uses of get_sha1_hex to get_oid_hexbrian m. carlson, May 2, 2018
  41. 08/42 packfile: abstract away hash constant valuesbrian m. carlson, May 2, 2018
  42. 04/42 packfile: remove unused member from struct pack_entrybrian m. carlson, May 2, 2018
  43. 03/42 Remove unused member in struct object_contextbrian m. carlson, May 2, 2018
  44. Duy NguyenMay 2, 2018
  45. brian m. carlsonMay 2, 2018

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