Merge branch 'mh/check-attr-relative'

* mh/check-attr-relative: (29 commits)
  test-path-utils: Add subcommand "prefix_path"
  test-path-utils: Add subcommand "absolute_path"
  git-check-attr: Normalize paths
  git-check-attr: Demonstrate problems with relative paths
  git-check-attr: Demonstrate problems with unnormalized paths
  git-check-attr: test that no output is written to stderr
  Rename git_checkattr() to git_check_attr()
  git-check-attr: Fix command-line handling to match docs
  git-check-attr: Drive two tests using the same raw data
  git-check-attr: Add an --all option to show all attributes
  git-check-attr: Error out if no pathnames are specified
  git-check-attr: Process command-line args more systematically
  git-check-attr: Handle each error separately
  git-check-attr: Extract a function error_with_usage()
  git-check-attr: Introduce a new variable
  git-check-attr: Extract a function output_attr()
  Allow querying all attributes on a file
  Remove redundant check
  Remove redundant call to bootstrap_attr_stack()
  Extract a function collect_all_attrs()
  ...

Documentation/git-check-attr.txt

@@ -9,8 +9,8 @@ git-check-attr - Display gitattributes information
 SYNOPSIS
 --------
 [verse]
-'git check-attr' attr... [--] pathname...
-'git check-attr' --stdin [-z] attr... < <list-of-paths>
+'git check-attr' [-a | --all | attr...] [--] pathname...
+'git check-attr' --stdin [-z] [-a | --all | attr...] < <list-of-paths>
 
 DESCRIPTION
 -----------
@@ -19,6 +19,11 @@ For every pathname, this command will list if each attribute is 'unspecified',
 
 OPTIONS
 -------
+-a, --all::
+	List all attributes that are associated with the specified
+	paths.  If this option is used, then 'unspecified' attributes
+	will not be included in the output.
+
 --stdin::
 	Read file names from stdin instead of from the command-line.
 
@@ -28,8 +33,11 @@ OPTIONS
 
 \--::
 	Interpret all preceding arguments as attributes and all following
-	arguments as path names. If not supplied, only the first argument will
-	be treated as an attribute.
+	arguments as path names.
+
+If none of `--stdin`, `--all`, or `--` is used, the first argument
+will be treated as an attribute and the rest of the arguments as
+pathnames.
 
 OUTPUT
 ------
@@ -69,6 +77,13 @@ org/example/MyClass.java: diff: java
 org/example/MyClass.java: myAttr: set
 ---------------
 
+* Listing all attributes for a file:
+---------------
+$ git check-attr --all -- org/example/MyClass.java
+org/example/MyClass.java: diff: java
+org/example/MyClass.java: myAttr: set
+---------------
+
 * Listing an attribute for multiple files:
 ---------------
 $ git check-attr myAttr -- org/example/MyClass.java org/example/NoMyAttr.java

Documentation/gitattributes.txt

@@ -955,6 +955,9 @@ frotz	unspecified
 ----------------------------------------------------------------
 
 
+SEE ALSO
+--------
+linkgit:git-check-attr[1].
 
 GIT
 ---

Documentation/technical/api-gitattributes.txt

@@ -11,27 +11,15 @@ Data Structure
 `struct git_attr`::
 
 	An attribute is an opaque object that is identified by its name.
-	Pass the name and its length to `git_attr()` function to obtain
-	the object of this type.  The internal representation of this
-	structure is of no interest to the calling programs.
+	Pass the name to `git_attr()` function to obtain the object of
+	this type.  The internal representation of this structure is
+	of no interest to the calling programs.  The name of the
+	attribute can be retrieved by calling `git_attr_name()`.
 
 `struct git_attr_check`::
 
 	This structure represents a set of attributes to check in a call
-	to `git_checkattr()` function, and receives the results.
-
-
-Calling Sequence
-----------------
-
-* Prepare an array of `struct git_attr_check` to define the list of
-  attributes you would want to check.  To populate this array, you would
-  need to define necessary attributes by calling `git_attr()` function.
-
-* Call git_checkattr() to check the attributes for the path.
-
-* Inspect `git_attr_check` structure to see how each of the attribute in
-  the array is defined for the path.
+	to `git_check_attr()` function, and receives the results.
 
 
 Attribute Values
@@ -57,6 +45,19 @@ If none of the above returns true, `.value` member points at a string
 value of the attribute for the path.
 
 
+Querying Specific Attributes
+----------------------------
+
+* Prepare an array of `struct git_attr_check` to define the list of
+  attributes you would want to check.  To populate this array, you would
+  need to define necessary attributes by calling `git_attr()` function.
+
+* Call `git_check_attr()` to check the attributes for the path.
+
+* Inspect `git_attr_check` structure to see how each of the attribute in
+  the array is defined for the path.
+
+
 Example
 -------
 
@@ -72,18 +73,18 @@ static void setup_check(void)
 {
 	if (check[0].attr)
 		return; /* already done */
-	check[0].attr = git_attr("crlf", 4);
-	check[1].attr = git_attr("ident", 5);
+	check[0].attr = git_attr("crlf");
+	check[1].attr = git_attr("ident");
 }
 ------------
 
-. Call `git_checkattr()` with the prepared array of `struct git_attr_check`:
+. Call `git_check_attr()` with the prepared array of `struct git_attr_check`:
 
 ------------
 	const char *path;
 
 	setup_check();
-	git_checkattr(path, ARRAY_SIZE(check), check);
+	git_check_attr(path, ARRAY_SIZE(check), check);
 ------------
 
 . Act on `.value` member of the result, left in `check[]`:
@@ -108,4 +109,20 @@ static void setup_check(void)
 	}
 ------------
 
-(JC)
+
+Querying All Attributes
+-----------------------
+
+To get the values of all attributes associated with a file:
+
+* Call `git_all_attrs()`, which returns an array of `git_attr_check`
+  structures.
+
+* Iterate over the `git_attr_check` array to examine the attribute
+  names and values.  The name of the attribute described by a
+  `git_attr_check` object can be retrieved via
+  `git_attr_name(check[i].attr)`.  (Please note that no items will be
+  returned for unset attributes, so `ATTR_UNSET()` will return false
+  for all returned `git_array_check` objects.)
+
+* Free the `git_array_check` array.

archive.c

@@ -123,7 +123,7 @@ static int write_archive_entry(const unsigned char *sha1, const char *base,
 	path_without_prefix = path.buf + args->baselen;
 
 	setup_archive_check(check);
-	if (!git_checkattr(path_without_prefix, ARRAY_SIZE(check), check)) {
+	if (!git_check_attr(path_without_prefix, ARRAY_SIZE(check), check)) {
 		if (ATTR_TRUE(check[0].value))
 			return 0;
 		convert = ATTR_TRUE(check[1].value);

attr.c

@@ -36,6 +36,11 @@ static int attr_nr;
 static struct git_attr_check *check_all_attr;
 static struct git_attr *(git_attr_hash[HASHSIZE]);
 
+char *git_attr_name(struct git_attr *attr)
+{
+	return attr->name;
+}
+
 static unsigned hash_name(const char *name, int namelen)
 {
 	unsigned val = 0, c;
@@ -50,12 +55,10 @@ static unsigned hash_name(const char *name, int namelen)
 static int invalid_attr_name(const char *name, int namelen)
 {
 	/*
-	 * Attribute name cannot begin with '-' and from
-	 * [-A-Za-z0-9_.].  We'd specifically exclude '=' for now,
-	 * as we might later want to allow non-binary value for
-	 * attributes, e.g. "*.svg	merge=special-merge-program-for-svg"
+	 * Attribute name cannot begin with '-' and must consist of
+	 * characters from [-A-Za-z0-9_.].
 	 */
-	if (*name == '-')
+	if (namelen <= 0 || *name == '-')
 		return -1;
 	while (namelen--) {
 		char ch = *name++;
@@ -532,11 +535,18 @@ static void bootstrap_attr_stack(void)
 	}
 }
 
-static void prepare_attr_stack(const char *path, int dirlen)
+static void prepare_attr_stack(const char *path)
 {
 	struct attr_stack *elem, *info;
-	int len;
+	int dirlen, len;
 	struct strbuf pathbuf;
+	const char *cp;
+
+	cp = strrchr(path, '/');
+	if (!cp)
+		dirlen = 0;
+	else
+		dirlen = cp - path;
 
 	strbuf_init(&pathbuf, dirlen+2+strlen(GITATTRIBUTES_FILE));
 
@@ -555,8 +565,7 @@ static void prepare_attr_stack(const char *path, int dirlen)
 	 * .gitattributes in deeper directories to shallower ones,
 	 * and finally use the built-in set as the default.
 	 */
-	if (!attr_stack)
-		bootstrap_attr_stack();
+	bootstrap_attr_stack();
 
 	/*
 	 * Pop the "info" one that is always at the top of the stack.
@@ -703,26 +712,30 @@ static int macroexpand_one(int attr_nr, int rem)
 	return rem;
 }
 
-int git_checkattr(const char *path, int num, struct git_attr_check *check)
+/*
+ * Collect all attributes for path into the array pointed to by
+ * check_all_attr.
+ */
+static void collect_all_attrs(const char *path)
 {
 	struct attr_stack *stk;
-	const char *cp;
-	int dirlen, pathlen, i, rem;
+	int i, pathlen, rem;
 
-	bootstrap_attr_stack();
+	prepare_attr_stack(path);
 	for (i = 0; i < attr_nr; i++)
 		check_all_attr[i].value = ATTR__UNKNOWN;
 
 	pathlen = strlen(path);
-	cp = strrchr(path, '/');
-	if (!cp)
-		dirlen = 0;
-	else
-		dirlen = cp - path;
-	prepare_attr_stack(path, dirlen);
 	rem = attr_nr;
 	for (stk = attr_stack; 0 < rem && stk; stk = stk->prev)
 		rem = fill(path, pathlen, stk, rem);
+}
+
+int git_check_attr(const char *path, int num, struct git_attr_check *check)
+{
+	int i;
+
+	collect_all_attrs(path);
 
 	for (i = 0; i < num; i++) {
 		const char *value = check_all_attr[check[i].attr->attr_nr].value;
@@ -734,6 +747,34 @@ int git_checkattr(const char *path, int num, struct git_attr_check *check)
 	return 0;
 }
 
+int git_all_attrs(const char *path, int *num, struct git_attr_check **check)
+{
+	int i, count, j;
+
+	collect_all_attrs(path);
+
+	/* Count the number of attributes that are set. */
+	count = 0;
+	for (i = 0; i < attr_nr; i++) {
+		const char *value = check_all_attr[i].value;
+		if (value != ATTR__UNSET && value != ATTR__UNKNOWN)
+			++count;
+	}
+	*num = count;
+	*check = xmalloc(sizeof(**check) * count);
+	j = 0;
+	for (i = 0; i < attr_nr; i++) {
+		const char *value = check_all_attr[i].value;
+		if (value != ATTR__UNSET && value != ATTR__UNKNOWN) {
+			(*check)[j].attr = check_all_attr[i].attr;
+			(*check)[j].value = value;
+			++j;
+		}
+	}
+
+	return 0;
+}
+
 void git_attr_set_direction(enum git_attr_direction new, struct index_state *istate)
 {
 	enum git_attr_direction old = direction;

attr.h

@@ -20,7 +20,7 @@ extern const char git_attr__false[];
 #define ATTR_UNSET(v) ((v) == NULL)
 
 /*
- * Send one or more git_attr_check to git_checkattr(), and
+ * Send one or more git_attr_check to git_check_attr(), and
  * each 'value' member tells what its value is.
  * Unset one is returned as NULL.
  */
@@ -29,7 +29,23 @@ struct git_attr_check {
 	const char *value;
 };
 
-int git_checkattr(const char *path, int, struct git_attr_check *);
+/*
+ * Return the name of the attribute represented by the argument.  The
+ * return value is a pointer to a null-delimited string that is part
+ * of the internal data structure; it should not be modified or freed.
+ */
+char *git_attr_name(struct git_attr *);
+
+int git_check_attr(const char *path, int, struct git_attr_check *);
+
+/*
+ * Retrieve all attributes that apply to the specified path.  *num
+ * will be set the the number of attributes on the path; **check will
+ * be set to point at a newly-allocated array of git_attr_check
+ * objects describing the attributes and their values.  *check must be
+ * free()ed by the caller.
+ */
+int git_all_attrs(const char *path, int *num, struct git_attr_check **check);
 
 enum git_attr_direction {
 	GIT_ATTR_CHECKIN,