From: Junio C Hamano <gitster@pobox.com>
Date: Thu, 7 Feb 2019 06:05:21 +0000 (-0800)
Subject: Merge branch 'dt/cat-file-batch-ambiguous'
X-Git-Tag: v2.21.0-rc0~27
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/cfd9167c15e7b09f3964204964a4c158108c6403?ds=inline;hp=-c

Merge branch 'dt/cat-file-batch-ambiguous'

"git cat-file --batch" reported a dangling symbolic link by
mistake, when it wanted to report that a given name is ambiguous.

* dt/cat-file-batch-ambiguous:
t1512: test ambiguous cat-file --batch and --batch-output
Do not print 'dangling' for cat-file in case of ambiguity
---

cfd9167c15e7b09f3964204964a4c158108c6403
diff --combined Documentation/git-cat-file.txt
index 9a2e9cdafb,e27a940985..8eca671b82
--- a/Documentation/git-cat-file.txt
+++ b/Documentation/git-cat-file.txt
@@@ -23,8 -23,8 +23,8 @@@ In the second form, a list of objects (
  stdin, and the SHA-1, type, and size of each object is printed on stdout. The
  output format can be overridden using the optional `<format>` argument. If
  either `--textconv` or `--filters` was specified, the input is expected to
 -list the object names followed by the path name, separated by a single white
 -space, so that the appropriate drivers can be determined.
 +list the object names followed by the path name, separated by a single
 +whitespace, so that the appropriate drivers can be determined.
  
  OPTIONS
  -------
@@@ -79,7 -79,7 +79,7 @@@
  	Print object information and contents for each object provided
  	on stdin.  May not be combined with any other options or arguments
  	except `--textconv` or `--filters`, in which case the input lines
 -	also need to specify the path, separated by white space.  See the
 +	also need to specify the path, separated by whitespace.  See the
  	section `BATCH OUTPUT` below for details.
  
  --batch-check::
@@@ -87,7 -87,7 +87,7 @@@
  	Print object information for each object provided on stdin.  May
  	not be combined with any other options or arguments except
  	`--textconv` or `--filters`, in which case the input lines also
 -	need to specify the path, separated by white space.  See the
 +	need to specify the path, separated by whitespace.  See the
  	section `BATCH OUTPUT` below for details.
  
  --batch-all-objects::
@@@ -252,6 -252,12 +252,12 @@@ the repository, then `cat-file` will ig
  <object> SP missing LF
  ------------
  
+ If a name is specified that might refer to more than one object (an ambiguous short sha), then `cat-file` will ignore any custom format and print:
+ 
+ ------------
+ <object> SP ambiguous LF
+ ------------
+ 
  If --follow-symlinks is used, and a symlink in the repository points
  outside the repository, then `cat-file` will ignore any custom format
  and print:
diff --combined cache.h
index 038e3764a9,70652e99dc..156a839484
--- a/cache.h
+++ b/cache.h
@@@ -45,20 -45,10 +45,20 @@@ unsigned long git_deflate_bound(git_zst
  /* The length in bytes and in hex digits of an object name (SHA-1 value). */
  #define GIT_SHA1_RAWSZ 20
  #define GIT_SHA1_HEXSZ (2 * GIT_SHA1_RAWSZ)
 +/* The block size of SHA-1. */
 +#define GIT_SHA1_BLKSZ 64
 +
 +/* The length in bytes and in hex digits of an object name (SHA-256 value). */
 +#define GIT_SHA256_RAWSZ 32
 +#define GIT_SHA256_HEXSZ (2 * GIT_SHA256_RAWSZ)
 +/* The block size of SHA-256. */
 +#define GIT_SHA256_BLKSZ 64
  
  /* The length in byte and in hex digits of the largest possible hash value. */
 -#define GIT_MAX_RAWSZ GIT_SHA1_RAWSZ
 -#define GIT_MAX_HEXSZ GIT_SHA1_HEXSZ
 +#define GIT_MAX_RAWSZ GIT_SHA256_RAWSZ
 +#define GIT_MAX_HEXSZ GIT_SHA256_HEXSZ
 +/* The largest possible block size for any supported hash. */
 +#define GIT_MAX_BLKSZ GIT_SHA256_BLKSZ
  
  struct object_id {
  	unsigned char hash[GIT_MAX_RAWSZ];
@@@ -755,7 -745,6 +755,7 @@@ extern int index_name_pos(const struct 
  #define ADD_CACHE_JUST_APPEND 8		/* Append only; tree.c::read_tree() */
  #define ADD_CACHE_NEW_ONLY 16		/* Do not replace existing ones */
  #define ADD_CACHE_KEEP_CACHE_TREE 32	/* Do not invalidate cache-tree */
 +#define ADD_CACHE_RENORMALIZE 64        /* Pass along HASH_RENORMALIZE */
  extern int add_index_entry(struct index_state *, struct cache_entry *ce, int option);
  extern void rename_index_entry_at(struct index_state *, int pos, const char *new_name);
  
@@@ -1039,12 -1028,16 +1039,12 @@@ extern const struct object_id null_oid
  static inline int hashcmp(const unsigned char *sha1, const unsigned char *sha2)
  {
  	/*
 -	 * This is a temporary optimization hack. By asserting the size here,
 -	 * we let the compiler know that it's always going to be 20, which lets
 -	 * it turn this fixed-size memcmp into a few inline instructions.
 -	 *
 -	 * This will need to be extended or ripped out when we learn about
 -	 * hashes of different sizes.
 +	 * Teach the compiler that there are only two possibilities of hash size
 +	 * here, so that it can optimize for this case as much as possible.
  	 */
 -	if (the_hash_algo->rawsz != 20)
 -		BUG("hash size not yet supported by hashcmp");
 -	return memcmp(sha1, sha2, the_hash_algo->rawsz);
 +	if (the_hash_algo->rawsz == GIT_MAX_RAWSZ)
 +		return memcmp(sha1, sha2, GIT_MAX_RAWSZ);
 +	return memcmp(sha1, sha2, GIT_SHA1_RAWSZ);
  }
  
  static inline int oidcmp(const struct object_id *oid1, const struct object_id *oid2)
@@@ -1054,13 -1047,7 +1054,13 @@@
  
  static inline int hasheq(const unsigned char *sha1, const unsigned char *sha2)
  {
 -	return !hashcmp(sha1, sha2);
 +	/*
 +	 * We write this here instead of deferring to hashcmp so that the
 +	 * compiler can properly inline it and avoid calling memcmp.
 +	 */
 +	if (the_hash_algo->rawsz == GIT_MAX_RAWSZ)
 +		return !memcmp(sha1, sha2, GIT_MAX_RAWSZ);
 +	return !memcmp(sha1, sha2, GIT_SHA1_RAWSZ);
  }
  
  static inline int oideq(const struct object_id *oid1, const struct object_id *oid2)
@@@ -1085,7 -1072,7 +1085,7 @@@ static inline void hashcpy(unsigned cha
  
  static inline void oidcpy(struct object_id *dst, const struct object_id *src)
  {
 -	hashcpy(dst->hash, src->hash);
 +	memcpy(dst->hash, src->hash, GIT_MAX_RAWSZ);
  }
  
  static inline struct object_id *oiddup(const struct object_id *src)
@@@ -1345,6 -1332,24 +1345,24 @@@ struct object_context 
  	GET_OID_TREE | GET_OID_TREEISH | \
  	GET_OID_BLOB)
  
+ enum get_oid_result {
+ 	FOUND = 0,
+ 	MISSING_OBJECT = -1, /* The requested object is missing */
+ 	SHORT_NAME_AMBIGUOUS = -2,
+ 	/* The following only apply when symlinks are followed */
+ 	DANGLING_SYMLINK = -4, /*
+ 				* The initial symlink is there, but
+ 				* (transitively) points to a missing
+ 				* in-tree file
+ 				*/
+ 	SYMLINK_LOOP = -5,
+ 	NOT_DIR = -6, /*
+ 		       * Somewhere along the symlink chain, a path is
+ 		       * requested which contains a file as a
+ 		       * non-final element.
+ 		       */
+ };
+ 
  extern int get_oid(const char *str, struct object_id *oid);
  extern int get_oid_commit(const char *str, struct object_id *oid);
  extern int get_oid_committish(const char *str, struct object_id *oid);
@@@ -1352,7 -1357,7 +1370,7 @@@ extern int get_oid_tree(const char *str
  extern int get_oid_treeish(const char *str, struct object_id *oid);
  extern int get_oid_blob(const char *str, struct object_id *oid);
  extern void maybe_die_on_misspelt_object_name(const char *name, const char *prefix);
- extern int get_oid_with_context(const char *str, unsigned flags, struct object_id *oid, struct object_context *oc);
+ extern enum get_oid_result get_oid_with_context(const char *str, unsigned flags, struct object_id *oid, struct object_context *oc);
  
  
  typedef int each_abbrev_fn(const struct object_id *oid, void *);
@@@ -1378,9 -1383,9 +1396,9 @@@ extern int get_oid_hex(const char *hex
  extern int hex_to_bytes(unsigned char *binary, const char *hex, size_t len);
  
  /*
 - * Convert a binary sha1 to its hex equivalent. The `_r` variant is reentrant,
 + * Convert a binary hash to its hex equivalent. The `_r` variant is reentrant,
   * and writes the NUL-terminated output to the buffer `out`, which must be at
 - * least `GIT_SHA1_HEXSZ + 1` bytes, and returns a pointer to out for
 + * least `GIT_MAX_HEXSZ + 1` bytes, and returns a pointer to out for
   * convenience.
   *
   * The non-`_r` variant returns a static buffer, but uses a ring of 4
@@@ -1388,13 -1393,10 +1406,13 @@@
   *
   *   printf("%s -> %s", sha1_to_hex(one), sha1_to_hex(two));
   */
 -extern char *sha1_to_hex_r(char *out, const unsigned char *sha1);
 -extern char *oid_to_hex_r(char *out, const struct object_id *oid);
 -extern char *sha1_to_hex(const unsigned char *sha1);	/* static buffer result! */
 -extern char *oid_to_hex(const struct object_id *oid);	/* same static buffer as sha1_to_hex */
 +char *hash_to_hex_algop_r(char *buffer, const unsigned char *hash, const struct git_hash_algo *);
 +char *sha1_to_hex_r(char *out, const unsigned char *sha1);
 +char *oid_to_hex_r(char *out, const struct object_id *oid);
 +char *hash_to_hex_algop(const unsigned char *hash, const struct git_hash_algo *);	/* static buffer result! */
 +char *sha1_to_hex(const unsigned char *sha1);						/* same static buffer */
 +char *hash_to_hex(const unsigned char *hash);						/* same static buffer */
 +char *oid_to_hex(const struct object_id *oid);						/* same static buffer */
  
  /*
   * Parse a 40-character hexadecimal object ID starting from hex, updating the
diff --combined tree-walk.c
index 277e3b3243,fb7959b21d..1e4bbc8a0e
--- a/tree-walk.c
+++ b/tree-walk.c
@@@ -48,8 -48,7 +48,8 @@@ static int decode_tree_entry(struct tre
  	/* Initialize the descriptor entry */
  	desc->entry.path = path;
  	desc->entry.mode = canon_mode(mode);
 -	desc->entry.oid  = (const struct object_id *)(path + len);
 +	desc->entry.pathlen = len - 1;
 +	hashcpy(desc->entry.oid.hash, (const unsigned char *)path + len);
  
  	return 0;
  }
@@@ -108,7 -107,7 +108,7 @@@ static void entry_extract(struct tree_d
  static int update_tree_entry_internal(struct tree_desc *desc, struct strbuf *err)
  {
  	const void *buf = desc->buffer;
 -	const unsigned char *end = desc->entry.oid->hash + the_hash_algo->rawsz;
 +	const unsigned char *end = (const unsigned char *)desc->entry.path + desc->entry.pathlen + 1 + the_hash_algo->rawsz;
  	unsigned long size = desc->size;
  	unsigned long len = end - (const unsigned char *)buf;
  
@@@ -176,11 -175,9 +176,11 @@@ void setup_traverse_info(struct travers
  		pathlen--;
  	info->pathlen = pathlen ? pathlen + 1 : 0;
  	info->name.path = base;
 -	info->name.oid = (void *)(base + pathlen + 1);
 -	if (pathlen)
 +	info->name.pathlen = pathlen;
 +	if (pathlen) {
 +		hashcpy(info->name.oid.hash, (const unsigned char *)base + pathlen + 1);
  		info->prev = &dummy;
 +	}
  }
  
  char *make_traverse_path(char *path, const struct traverse_info *info, const struct name_entry *n)
@@@ -505,10 -502,10 +505,10 @@@ static int find_tree_entry(struct tree_
  	int namelen = strlen(name);
  	while (t->size) {
  		const char *entry;
 -		const struct object_id *oid;
 +		struct object_id oid;
  		int entrylen, cmp;
  
 -		oid = tree_entry_extract(t, &entry, mode);
 +		oidcpy(&oid, tree_entry_extract(t, &entry, mode));
  		entrylen = tree_entry_len(&t->entry);
  		update_tree_entry(t);
  		if (entrylen > namelen)
@@@ -519,7 -516,7 +519,7 @@@
  		if (cmp < 0)
  			break;
  		if (entrylen == namelen) {
 -			oidcpy(result, oid);
 +			oidcpy(result, &oid);
  			return 0;
  		}
  		if (name[entrylen] != '/')
@@@ -527,10 -524,10 +527,10 @@@
  		if (!S_ISDIR(*mode))
  			break;
  		if (++entrylen == namelen) {
 -			oidcpy(result, oid);
 +			oidcpy(result, &oid);
  			return 0;
  		}
 -		return get_tree_entry(oid, name + entrylen, result, mode);
 +		return get_tree_entry(&oid, name + entrylen, result, mode);
  	}
  	return -1;
  }
@@@ -582,10 -579,10 +582,10 @@@ int get_tree_entry(const struct object_
   * with the sha1 of the found object, and *mode will hold the mode of
   * the object.
   *
-  * See the code for enum follow_symlink_result for a description of
+  * See the code for enum get_oid_result for a description of
   * the return values.
   */
- enum follow_symlinks_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode)
+ enum get_oid_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode)
  {
  	int retval = MISSING_OBJECT;
  	struct dir_state *parents = NULL;
diff --combined tree-walk.h
index a4ad28ea5e,de6b95179d..8225171866
--- a/tree-walk.h
+++ b/tree-walk.h
@@@ -1,12 -1,12 +1,12 @@@
  #ifndef TREE_WALK_H
  #define TREE_WALK_H
  
 -struct index_state;
 -struct strbuf;
 +#include "cache.h"
  
  struct name_entry {
 -	const struct object_id *oid;
 +	struct object_id oid;
  	const char *path;
 +	int pathlen;
  	unsigned int mode;
  };
  
@@@ -20,12 -20,12 +20,12 @@@ static inline const struct object_id *t
  {
  	*pathp = desc->entry.path;
  	*modep = desc->entry.mode;
 -	return desc->entry.oid;
 +	return &desc->entry.oid;
  }
  
  static inline int tree_entry_len(const struct name_entry *ne)
  {
 -	return (const char *)ne->oid - ne->path - 1;
 +	return ne->pathlen;
  }
  
  /*
@@@ -51,23 -51,7 +51,7 @@@ struct traverse_info
  typedef int (*traverse_callback_t)(int n, unsigned long mask, unsigned long dirmask, struct name_entry *entry, struct traverse_info *);
  int traverse_trees(struct index_state *istate, int n, struct tree_desc *t, struct traverse_info *info);
  
- enum follow_symlinks_result {
- 	FOUND = 0, /* This includes out-of-tree links */
- 	MISSING_OBJECT = -1, /* The initial symlink is missing */
- 	DANGLING_SYMLINK = -2, /*
- 				* The initial symlink is there, but
- 				* (transitively) points to a missing
- 				* in-tree file
- 				*/
- 	SYMLINK_LOOP = -3,
- 	NOT_DIR = -4, /*
- 		       * Somewhere along the symlink chain, a path is
- 		       * requested which contains a file as a
- 		       * non-final element.
- 		       */
- };
- 
- enum follow_symlinks_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode);
+ enum get_oid_result get_tree_entry_follow_symlinks(struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned *mode);
  
  struct traverse_info {
  	const char *traverse_path;