Merge pull request #531 from arrbee/gitignore

Initial implementation of gitignore support

git_status_foreach() and git_status_file() will now be
gitignore aware.

15 files changed, 555 insertions, 175 deletions

diff --git a/src/attr.c b/src/attr.c
index 679380bba..dc42379ff 100644
--- a/src/attr.c
+++ b/src/attr.c
@@ -3,15 +3,9 @@
 #include "config.h"
 #include <ctype.h>
 
-#define GIT_ATTR_FILE_INREPO	"info/attributes"
-#define GIT_ATTR_FILE			".gitattributes"
-#define GIT_ATTR_FILE_SYSTEM	"gitattributes"
-
 static int collect_attr_files(
 	git_repository *repo, const char *path, git_vector *files);
 
-static int attr_cache_init(git_repository *repo);
-
 
 int git_attr_get(
     git_repository *repo, const char *pathname,
@@ -186,7 +180,7 @@ int git_attr_add_macro(
 	int error;
 	git_attr_rule *macro = NULL;
 
-	if ((error = attr_cache_init(repo)) < GIT_SUCCESS)
+	if ((error = git_attr_cache__init(repo)) < GIT_SUCCESS)
 		return error;
 
 	macro = git__calloc(1, sizeof(git_attr_rule));
@@ -215,11 +209,12 @@ int git_attr_add_macro(
 
 
 /* add git_attr_file to vector of files, loading if needed */
-static int push_attrs(
+int git_attr_cache__push_file(
 	git_repository *repo,
-	git_vector     *files,
+	git_vector     *stack,
 	const char     *base,
-	const char     *filename)
+	const char     *filename,
+	int (*loader)(git_repository *, const char *, git_attr_file **))
 {
 	int error = GIT_SUCCESS;
 	git_attr_cache *cache = &repo->attrcache;
@@ -227,23 +222,22 @@ static int push_attrs(
 	git_attr_file *file;
 	int add_to_cache = 0;
 
-	if ((error = git_path_prettify(&path, filename, base)) < GIT_SUCCESS) {
-		if (error == GIT_EOSERR)
-			/* file was not found -- ignore error */
-			error = GIT_SUCCESS;
-		goto cleanup;
+	if (base != NULL) {
+		if ((error = git_buf_joinpath(&path, base, filename)) < GIT_SUCCESS)
+			goto cleanup;
+		filename = path.ptr;
 	}
 
 	/* either get attr_file from cache or read from disk */
-	file = git_hashtable_lookup(cache->files, path.ptr);
-	if (file == NULL) {
-		error = git_attr_file__from_file(repo, path.ptr, &file);
+	file = git_hashtable_lookup(cache->files, filename);
+	if (file == NULL && git_futils_exists(filename) == GIT_SUCCESS) {
+		error = (*loader)(repo, filename, &file);
 		add_to_cache = (error == GIT_SUCCESS);
 	}
 
 	if (file != NULL) {
 		/* add file to vector, if we found it */
-		error = git_vector_insert(files, file);
+		error = git_vector_insert(stack, file);
 
 		/* add file to cache, if it is new */
 		/* do this after above step b/c it is not critical */
@@ -256,6 +250,19 @@ cleanup:
 	return error;
 }
 
+#define push_attrs(R,S,B,F) \
+	git_attr_cache__push_file((R),(S),(B),(F),git_attr_file__from_file)
+
+typedef struct {
+	git_repository *repo;
+	git_vector *files;
+} attr_walk_up_info;
+
+static int push_one_attr(void *ref, git_buf *path)
+{
+	attr_walk_up_info *info = (attr_walk_up_info *)ref;
+	return push_attrs(info->repo, info->files, path->ptr, GIT_ATTR_FILE);
+}
 
 static int collect_attr_files(
 	git_repository *repo, const char *path, git_vector *files)
@@ -264,23 +271,17 @@ static int collect_attr_files(
 	git_buf dir = GIT_BUF_INIT;
 	git_config *cfg;
 	const char *workdir = git_repository_workdir(repo);
+	attr_walk_up_info info;
 
-	if ((error = attr_cache_init(repo)) < GIT_SUCCESS)
+	if ((error = git_attr_cache__init(repo)) < GIT_SUCCESS)
 		goto cleanup;
 
 	if ((error = git_vector_init(files, 4, NULL)) < GIT_SUCCESS)
 		goto cleanup;
 
-	if ((error = git_path_prettify(&dir, path, workdir)) < GIT_SUCCESS)
+	if ((error = git_futils_dir_for_path(&dir, path, workdir)) < GIT_SUCCESS)
 		goto cleanup;
 
-	if (git_futils_isdir(dir.ptr) != GIT_SUCCESS) {
-		git_path_dirname_r(&dir, dir.ptr);
-		git_path_to_dir(&dir);
-		if ((error = git_buf_lasterror(&dir)) < GIT_SUCCESS)
-			goto cleanup;
-	}
-
 	/* in precendence order highest to lowest:
 	 * - $GIT_DIR/info/attributes
 	 * - path components with .gitattributes
@@ -292,26 +293,15 @@ static int collect_attr_files(
 	if (error < GIT_SUCCESS)
 		goto cleanup;
 
-	if (workdir && git__prefixcmp(dir.ptr, workdir) == 0) {
-		ssize_t rootlen = (ssize_t)strlen(workdir);
-
-		do {
-			error = push_attrs(repo, files, dir.ptr, GIT_ATTR_FILE);
-			if (error == GIT_SUCCESS) {
-				git_path_dirname_r(&dir, dir.ptr);
-				git_path_to_dir(&dir);
-				error = git_buf_lasterror(&dir);
-			}
-		} while (!error && dir.size >= rootlen);
-	} else {
-		error = push_attrs(repo, files, dir.ptr, GIT_ATTR_FILE);
-	}
+	info.repo = repo;
+	info.files = files;
+	error = git_path_walk_up(&dir, workdir, push_one_attr, &info);
 	if (error < GIT_SUCCESS)
 		goto cleanup;
 
-	if (git_repository_config(&cfg, repo) == GIT_SUCCESS) {
+	if ((error = git_repository_config(&cfg, repo)) == GIT_SUCCESS) {
 		const char *core_attribs = NULL;
-		git_config_get_string(cfg, "core.attributesfile", &core_attribs);
+		git_config_get_string(cfg, GIT_ATTR_CONFIG, &core_attribs);
 		git_clearerror(); /* don't care if attributesfile is not set */
 		if (core_attribs)
 			error = push_attrs(repo, files, NULL, core_attribs);
@@ -337,7 +327,7 @@ static int collect_attr_files(
 }
 
 
-static int attr_cache_init(git_repository *repo)
+int git_attr_cache__init(git_repository *repo)
 {
 	int error = GIT_SUCCESS;
 	git_attr_cache *cache = &repo->attrcache;
@@ -367,7 +357,6 @@ static int attr_cache_init(git_repository *repo)
 	return error;
 }
 
-
 void git_attr_cache_flush(
 	git_repository *repo)
 {
@@ -398,3 +387,12 @@ void git_attr_cache_flush(
 
 	repo->attrcache.initialized = 0;
 }
+
+int git_attr_cache__insert_macro(git_repository *repo, git_attr_rule *macro)
+{
+	if (macro->assigns.length == 0)
+		return git__throw(GIT_EMISSINGOBJDATA, "git attribute macro with no values");
+
+	return git_hashtable_insert(
+		repo->attrcache.macros, macro->match.pattern, macro);
+}
diff --git a/src/attr.h b/src/attr.h
new file mode 100644
index 000000000..5edff30d1
--- /dev/null
+++ b/src/attr.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2009-2011 the libgit2 contributors
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_attr_h__
+#define INCLUDE_attr_h__
+
+#include "attr_file.h"
+
+typedef struct {
+	int initialized;
+	git_hashtable *files;	/* hash path to git_attr_file of rules */
+	git_hashtable *macros;	/* hash name to vector<git_attr_assignment> */
+} git_attr_cache;
+
+extern int git_attr_cache__init(git_repository *repo);
+
+extern int git_attr_cache__insert_macro(
+	git_repository *repo, git_attr_rule *macro);
+
+extern int git_attr_cache__push_file(
+	git_repository *repo,
+	git_vector     *stack,
+	const char     *base,
+	const char     *filename,
+	int (*loader)(git_repository *, const char *, git_attr_file **));
+
+#endif
diff --git a/src/attr_file.c b/src/attr_file.c
index fe8844e2d..5ea07c984 100644
--- a/src/attr_file.c
+++ b/src/attr_file.c
@@ -6,17 +6,29 @@
 const char *git_attr__true  = "[internal]__TRUE__";
 const char *git_attr__false = "[internal]__FALSE__";
 
-static int git_attr_fnmatch__parse(git_attr_fnmatch *spec, const char **base);
 static int sort_by_hash_and_name(const void *a_raw, const void *b_raw);
 static void git_attr_rule__clear(git_attr_rule *rule);
 
-int git_attr_cache__insert_macro(git_repository *repo, git_attr_rule *macro)
+int git_attr_file__new(git_attr_file **attrs_ptr)
 {
-	if (macro->assigns.length == 0)
-		return git__throw(GIT_EMISSINGOBJDATA, "git attribute macro with no values");
+	int error;
+	git_attr_file *attrs = NULL;
+
+	attrs = git__calloc(1, sizeof(git_attr_file));
+	if (attrs == NULL)
+		error = GIT_ENOMEM;
+	else
+		error = git_vector_init(&attrs->rules, 4, NULL);
+
+	if (error != GIT_SUCCESS) {
+		git__rethrow(error, "Could not allocate attribute storage");
+		git__free(attrs);
+		attrs = NULL;
+	}
+
+	*attrs_ptr = attrs;
 
-	return git_hashtable_insert(
-		repo->attrcache.macros, macro->match.pattern, macro);
+	return error;
 }
 
 int git_attr_file__from_buffer(
@@ -29,17 +41,8 @@ int git_attr_file__from_buffer(
 
 	*out = NULL;
 
-	attrs = git__calloc(1, sizeof(git_attr_file));
-	if (attrs == NULL)
-		return git__throw(GIT_ENOMEM, "Could not allocate attribute storage");
-
-	attrs->path = NULL;
-
-	error = git_vector_init(&attrs->rules, 4, NULL);
-	if (error != GIT_SUCCESS) {
-		git__rethrow(error, "Could not initialize attribute storage");
+	if ((error = git_attr_file__new(&attrs)) < GIT_SUCCESS)
 		goto cleanup;
-	}
 
 	scan = buffer;
 
@@ -166,19 +169,28 @@ int git_attr_file__lookup_one(
 }
 
 
-int git_attr_rule__match_path(
-	git_attr_rule *rule,
+int git_attr_fnmatch__match(
+	git_attr_fnmatch *match,
 	const git_attr_path *path)
 {
 	int matched = FNM_NOMATCH;
 
-	if (rule->match.flags & GIT_ATTR_FNMATCH_DIRECTORY && !path->is_dir)
+	if (match->flags & GIT_ATTR_FNMATCH_DIRECTORY && !path->is_dir)
 		return matched;
 
-	if (rule->match.flags & GIT_ATTR_FNMATCH_FULLPATH)
-		matched = p_fnmatch(rule->match.pattern, path->path, FNM_PATHNAME);
+	if (match->flags & GIT_ATTR_FNMATCH_FULLPATH)
+		matched = p_fnmatch(match->pattern, path->path, FNM_PATHNAME);
 	else
-		matched = p_fnmatch(rule->match.pattern, path->basename, 0);
+		matched = p_fnmatch(match->pattern, path->basename, 0);
+
+	return matched;
+}
+
+int git_attr_rule__match(
+	git_attr_rule *rule,
+	const git_attr_path *path)
+{
+	int matched = git_attr_fnmatch__match(&rule->match, path);
 
 	if (rule->match.flags & GIT_ATTR_FNMATCH_NEGATIVE)
 		matched = (matched == GIT_SUCCESS) ? FNM_NOMATCH : GIT_SUCCESS;
@@ -186,6 +198,7 @@ int git_attr_rule__match_path(
 	return matched;
 }
 
+
 git_attr_assignment *git_attr_rule__lookup_assignment(
 	git_attr_rule *rule, const char *name)
 {
@@ -203,6 +216,7 @@ git_attr_assignment *git_attr_rule__lookup_assignment(
 int git_attr_path__init(
 	git_attr_path *info, const char *path)
 {
+	assert(info && path);
 	info->path = path;
 	info->basename = strrchr(path, '/');
 	if (info->basename)
@@ -251,23 +265,21 @@ int git_attr_path__init(
  * GIT_ENOTFOUND if the fnmatch does not require matching, or
  * another error code there was an actual problem.
  */
-static int git_attr_fnmatch__parse(
+int git_attr_fnmatch__parse(
 	git_attr_fnmatch *spec,
 	const char **base)
 {
-	const char *pattern;
-	const char *scan;
+	const char *pattern, *scan;
 	int slash_count;
-	int error = GIT_SUCCESS;
 
-	assert(base && *base);
+	assert(spec && base && *base);
 
 	pattern = *base;
 
 	while (isspace(*pattern)) pattern++;
 	if (!*pattern || *pattern == '#') {
-		error = GIT_ENOTFOUND;
-		goto skip_to_eol;
+		*base = git__next_line(pattern);
+		return GIT_ENOTFOUND;
 	}
 
 	spec->flags = 0;
@@ -276,11 +288,8 @@ static int git_attr_fnmatch__parse(
 		if (strncmp(pattern, "[attr]", 6) == 0) {
 			spec->flags = spec->flags | GIT_ATTR_FNMATCH_MACRO;
 			pattern += 6;
-		} else {
-			/* unrecognized meta instructions - skip the line */
-			error = GIT_ENOTFOUND;
-			goto skip_to_eol;
 		}
+		/* else a character range like [a-e]* which is accepted */
 	}
 
 	if (*pattern == '!') {
@@ -290,6 +299,7 @@ static int git_attr_fnmatch__parse(
 
 	slash_count = 0;
 	for (scan = pattern; *scan != '\0'; ++scan) {
+		/* scan until (non-escaped) white space */
 		if (isspace(*scan) && *(scan - 1) != '\\')
 			break;
 
@@ -300,13 +310,15 @@ static int git_attr_fnmatch__parse(
 	}
 
 	*base = scan;
+
 	spec->length = scan - pattern;
 	spec->pattern = git__strndup(pattern, spec->length);
 
 	if (!spec->pattern) {
-		error = GIT_ENOMEM;
-		goto skip_to_eol;
+		*base = git__next_line(pattern);
+		return GIT_ENOMEM;
 	} else {
+		/* remove '\' that might have be used for internal whitespace */
 		char *from = spec->pattern, *to = spec->pattern;
 		while (*from) {
 			if (*from == '\\') {
@@ -327,14 +339,6 @@ static int git_attr_fnmatch__parse(
 	}
 
 	return GIT_SUCCESS;
-
-skip_to_eol:
-	/* skip to end of line */
-	while (*pattern && *pattern != '\n') pattern++;
-	if (*pattern == '\n') pattern++;
-	*base = pattern;
-
-	return error;
 }
 
 static int sort_by_hash_and_name(const void *a_raw, const void *b_raw)
@@ -494,10 +498,7 @@ int git_attr_assignment__parse(
 	if (assign != NULL)
 		git_attr_assignment__free(assign);
 
-	while (*scan && *scan != '\n') scan++;
-	if (*scan == '\n') scan++;
-
-	*base = scan;
+	*base = git__next_line(scan);
 
 	return error;
 }
@@ -510,14 +511,15 @@ static void git_attr_rule__clear(git_attr_rule *rule)
 	if (!rule)
 		return;
 
+	if (!(rule->match.flags & GIT_ATTR_FNMATCH_IGNORE)) {
+		git_vector_foreach(&rule->assigns, i, assign)
+			GIT_REFCOUNT_DEC(assign, git_attr_assignment__free);
+		git_vector_free(&rule->assigns);
+	}
+
 	git__free(rule->match.pattern);
 	rule->match.pattern = NULL;
 	rule->match.length = 0;
-
-	git_vector_foreach(&rule->assigns, i, assign)
-		GIT_REFCOUNT_DEC(assign, git_attr_assignment__free);
-
-	git_vector_free(&rule->assigns);
 }
 
 void git_attr_rule__free(git_attr_rule *rule)
diff --git a/src/attr_file.h b/src/attr_file.h
index bed440d61..7190c4c7b 100644
--- a/src/attr_file.h
+++ b/src/attr_file.h
@@ -11,10 +11,16 @@
 #include "vector.h"
 #include "hashtable.h"
 
+#define GIT_ATTR_FILE			".gitattributes"
+#define GIT_ATTR_FILE_INREPO	"info/attributes"
+#define GIT_ATTR_FILE_SYSTEM	"gitattributes"
+#define GIT_ATTR_CONFIG			"core.attributesfile"
+
 #define GIT_ATTR_FNMATCH_NEGATIVE	(1U << 0)
 #define GIT_ATTR_FNMATCH_DIRECTORY	(1U << 1)
 #define GIT_ATTR_FNMATCH_FULLPATH	(1U << 2)
 #define GIT_ATTR_FNMATCH_MACRO		(1U << 3)
+#define GIT_ATTR_FNMATCH_IGNORE		(1U << 4)
 
 typedef struct {
 	char *pattern;
@@ -23,13 +29,18 @@ typedef struct {
 } git_attr_fnmatch;
 
 typedef struct {
+	git_attr_fnmatch match;
+	git_vector assigns;		/* vector of <git_attr_assignment*> */
+} git_attr_rule;
+
+typedef struct {
 	git_refcount unused;
 	const char *name;
     unsigned long name_hash;
 } git_attr_name;
 
 typedef struct {
-	git_refcount rc;			/* for macros */
+	git_refcount rc;		/* for macros */
 	char *name;
     unsigned long name_hash;
     const char *value;
@@ -37,13 +48,8 @@ typedef struct {
 } git_attr_assignment;
 
 typedef struct {
-	git_attr_fnmatch match;
-	git_vector assigns;			/* vector of <git_attr_assignment*> */
-} git_attr_rule;
-
-typedef struct {
-	char *path;					/* cache the path this was loaded from */
-	git_vector rules;			/* vector of <git_attr_rule*> */
+	char *path;				/* cache the path this was loaded from */
+	git_vector rules;		/* vector of <rule*> or <fnmatch*> */
 } git_attr_file;
 
 typedef struct {
@@ -52,12 +58,6 @@ typedef struct {
 	int is_dir;
 } git_attr_path;
 
-typedef struct {
-	int initialized;
-	git_hashtable *files;	  /* hash path to git_attr_file */
-	git_hashtable *macros;	  /* hash name to vector<git_attr_assignment> */
-} git_attr_cache;
-
 /*
  * git_attr_file API
  */
@@ -67,6 +67,7 @@ extern int git_attr_file__from_buffer(
 extern int git_attr_file__from_file(
 	git_repository *repo, const char *path, git_attr_file **out);
 
+extern int git_attr_file__new(git_attr_file **attrs_ptr);
 extern void git_attr_file__free(git_attr_file *file);
 
 extern int git_attr_file__lookup_one(
@@ -78,7 +79,7 @@ extern int git_attr_file__lookup_one(
 /* loop over rules in file from bottom to top */
 #define git_attr_file__foreach_matching_rule(file, path, iter, rule)	\
 	git_vector_rforeach(&(file)->rules, (iter), (rule)) \
-		if (git_attr_rule__match_path((rule), (path)) == GIT_SUCCESS)
+		if (git_attr_rule__match((rule), (path)) == GIT_SUCCESS)
 
 extern unsigned long git_attr_file__name_hash(const char *name);
 
@@ -87,9 +88,17 @@ extern unsigned long git_attr_file__name_hash(const char *name);
  * other utilities
  */
 
+extern int git_attr_fnmatch__parse(
+	git_attr_fnmatch *spec,
+	const char **base);
+
+extern int git_attr_fnmatch__match(
+	git_attr_fnmatch *rule,
+	const git_attr_path *path);
+
 extern void git_attr_rule__free(git_attr_rule *rule);
 
-extern int git_attr_rule__match_path(
+extern int git_attr_rule__match(
 	git_attr_rule *rule,
 	const git_attr_path *path);
 
@@ -104,7 +113,4 @@ extern int git_attr_assignment__parse(
 	git_vector *assigns,
 	const char **scan);
 
-extern int git_attr_cache__insert_macro(
-	git_repository *repo, git_attr_rule *macro);
-
 #endif
diff --git a/src/buffer.c b/src/buffer.c
index def3496ce..c57e4aa1b 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -111,8 +111,10 @@ int git_buf_set(git_buf *buf, const char *data, size_t len)
 	if (len == 0 || data == NULL) {
 		git_buf_clear(buf);
 	} else {
-		ENSURE_SIZE(buf, len + 1);
-		memmove(buf->ptr, data, len);
+		if (data != buf->ptr) {
+			ENSURE_SIZE(buf, len + 1);
+			memmove(buf->ptr, data, len);
+		}
 		buf->size = len;
 		buf->ptr[buf->size] = '\0';
 	}
@@ -179,7 +181,7 @@ void git_buf_copy_cstr(char *data, size_t datasize, const git_buf *buf)
 {
 	size_t copylen;
 
-	assert(data && datasize);
+	assert(data && datasize && buf);
 
 	data[0] = '\0';
 
@@ -205,7 +207,7 @@ void git_buf_consume(git_buf *buf, const char *end)
 
 void git_buf_truncate(git_buf *buf, ssize_t len)
 {
-	if (len < buf->size) {
+	if (len >= 0 && len < buf->size) {
 		buf->size = len;
 		buf->ptr[buf->size] = '\0';
 	}
diff --git a/src/buffer.h b/src/buffer.h
index 52fd9a678..d06358527 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -102,9 +102,16 @@ GIT_INLINE(const char *) git_buf_cstr(git_buf *buf)
 	return buf->ptr;
 }
 
-
 void git_buf_copy_cstr(char *data, size_t datasize, const git_buf *buf);
 
 #define git_buf_PUTS(buf, str) git_buf_put(buf, str, sizeof(str) - 1)
 
+GIT_INLINE(int) git_buf_rfind_next(git_buf *buf, char ch)
+{
+	int idx = buf->size - 1;
+	while (idx >= 0 && buf->ptr[idx] == ch) idx--;
+	while (idx >= 0 && buf->ptr[idx] != ch) idx--;
+	return idx;
+}
+
 #endif
diff --git a/src/fileops.c b/src/fileops.c
index 48bd3514d..3412a47e2 100644
--- a/src/fileops.c
+++ b/src/fileops.c
@@ -534,3 +534,28 @@ int git_futils_find_system_file(git_buf *path, const char *filename)
 #endif
 }
 
+int git_futils_dir_for_path(git_buf *dir, const char *path, const char *base)
+{
+	int error = GIT_SUCCESS;
+
+	if (base != NULL && git_path_root(path) < 0)
+		error = git_buf_joinpath(dir, base, path);
+	else
+		error = git_buf_sets(dir, path);
+
+	if (error == GIT_SUCCESS) {
+		char buf[GIT_PATH_MAX];
+		if (p_realpath(dir->ptr, buf) != NULL)
+			error = git_buf_sets(dir, buf);
+	}
+
+	/* call dirname if this is not a directory */
+	if (error == GIT_SUCCESS && git_futils_isdir(dir->ptr) != GIT_SUCCESS)
+		if (git_path_dirname_r(dir, dir->ptr) < GIT_SUCCESS)
+			error = git_buf_lasterror(dir);
+
+	if (error == GIT_SUCCESS)
+		error = git_path_to_dir(dir);
+
+	return error;
+}
diff --git a/src/fileops.h b/src/fileops.h
index 31f3e6a91..91903a731 100644
--- a/src/fileops.h
+++ b/src/fileops.h
@@ -102,6 +102,16 @@ extern int git_futils_mkpath2file(const char *path, const mode_t mode);
 extern int git_futils_rmdir_r(const char *path, int force);
 
 /**
+ * Get the directory for a path.
+ *
+ * If the path is a directory, this does nothing (save append a '/' as
+ * needed).  If path is a normal file, this gets the directory containing
+ * it.  If the path does not exist, then this treats it a filename and
+ * returns the dirname of it.
+ */
+extern int git_futils_dir_for_path(git_buf *dir, const char *path, const char *base);
+
+/**
  * Create and open a temporary file with a `_git2_` suffix.
  * Writes the filename into path_out.
  * @return On success, an open file descriptor, else an error code < 0.
diff --git a/src/ignore.c b/src/ignore.c
new file mode 100644
index 000000000..1040574d7
--- /dev/null
+++ b/src/ignore.c
@@ -0,0 +1,159 @@
+#include "ignore.h"
+#include "path.h"
+#include "git2/config.h"
+
+#define GIT_IGNORE_INTERNAL		"[internal]exclude"
+#define GIT_IGNORE_FILE_INREPO	"info/exclude"
+#define GIT_IGNORE_FILE			".gitignore"
+#define GIT_IGNORE_CONFIG		"core.excludesfile"
+
+static int load_ignore_file(
+	git_repository *GIT_UNUSED(repo), const char *path, git_attr_file **out)
+{
+	int error = GIT_SUCCESS;
+	git_fbuffer fbuf = GIT_FBUFFER_INIT;
+	git_attr_file *ignores = NULL;
+	git_attr_fnmatch *match = NULL;
+	const char *scan = NULL;
+
+	GIT_UNUSED_ARG(repo);
+
+	*out = NULL;
+
+	if ((error = git_futils_readbuffer(&fbuf, path)) == GIT_SUCCESS)
+		error = git_attr_file__new(&ignores);
+
+	ignores->path = git__strdup(path);
+
+	scan = fbuf.data;
+
+	while (error == GIT_SUCCESS && *scan) {
+		if (!match && !(match = git__calloc(1, sizeof(git_attr_fnmatch)))) {
+			error = GIT_ENOMEM;
+			break;
+		}
+
+		if (!(error = git_attr_fnmatch__parse(match, &scan))) {
+			match->flags = match->flags | GIT_ATTR_FNMATCH_IGNORE;
+			scan = git__next_line(scan);
+			error = git_vector_insert(&ignores->rules, match);
+		}
+
+		if (error != GIT_SUCCESS) {
+			git__free(match->pattern);
+			match->pattern = NULL;
+
+			if (error == GIT_ENOTFOUND)
+				error = GIT_SUCCESS;
+		} else {
+			match = NULL; /* vector now "owns" the match */
+		}
+	}
+
+	git_futils_freebuffer(&fbuf);
+	git__free(match);
+
+	if (error != GIT_SUCCESS) {
+		git__rethrow(error, "Could not open ignore file '%s'", path);
+		git_attr_file__free(ignores);
+	} else {
+		*out = ignores;
+	}
+
+	return error;
+}
+
+#define push_ignore(R,S,B,F) \
+	git_attr_cache__push_file((R),(S),(B),(F),load_ignore_file)
+
+typedef struct {
+	git_repository *repo;
+	git_vector *stack;
+} ignore_walk_up_info;
+
+static int push_one_ignore(void *ref, git_buf *path)
+{
+	ignore_walk_up_info *info = (ignore_walk_up_info *)ref;
+	return push_ignore(info->repo, info->stack, path->ptr, GIT_IGNORE_FILE);
+}
+
+int git_ignore__for_path(git_repository *repo, const char *path, git_vector *stack)
+{
+	int error = GIT_SUCCESS;
+	git_buf dir = GIT_BUF_INIT;
+	git_config *cfg;
+	const char *workdir = git_repository_workdir(repo);
+	ignore_walk_up_info info;
+
+	if ((error = git_attr_cache__init(repo)) < GIT_SUCCESS)
+		goto cleanup;
+
+	if ((error = git_futils_dir_for_path(&dir, path, workdir)) < GIT_SUCCESS)
+		goto cleanup;
+
+	/* insert internals */
+	if ((error = push_ignore(repo, stack, NULL, GIT_IGNORE_INTERNAL)) < GIT_SUCCESS)
+		goto cleanup;
+
+	/* load .gitignore up the path */
+	info.repo = repo;
+	info.stack = stack;
+	if ((error = git_path_walk_up(&dir, workdir, push_one_ignore, &info)) < GIT_SUCCESS)
+		goto cleanup;
+
+	/* load .git/info/exclude */
+	if ((error = push_ignore(repo, stack, repo->path_repository, GIT_IGNORE_FILE_INREPO)) < GIT_SUCCESS)
+		goto cleanup;
+
+	/* load core.excludesfile */
+	if ((error = git_repository_config(&cfg, repo)) == GIT_SUCCESS) {
+		const char *core_ignore;
+		error = git_config_get_string(cfg, GIT_IGNORE_CONFIG, &core_ignore);
+		if (error == GIT_SUCCESS && core_ignore != NULL)
+			error = push_ignore(repo, stack, NULL, core_ignore);
+		else {
+			error = GIT_SUCCESS;
+			git_clearerror(); /* don't care if attributesfile is not set */
+		}
+		git_config_free(cfg);
+	}
+
+cleanup:
+	if (error < GIT_SUCCESS)
+		git__rethrow(error, "Could not get ignore files for '%s'", path);
+
+	git_buf_free(&dir);
+
+	return error;
+}
+
+void git_ignore__free(git_vector *stack)
+{
+	git_vector_free(stack);
+}
+
+int git_ignore__lookup(git_vector *stack, const char *pathname, int *ignored)
+{
+	int error;
+	unsigned int i, j;
+	git_attr_file *file;
+	git_attr_path path;
+	git_attr_fnmatch *match;
+
+	if ((error = git_attr_path__init(&path, pathname)) < GIT_SUCCESS)
+		return git__rethrow(error, "Could not get attribute for '%s'", pathname);
+
+	*ignored = 0;
+
+	git_vector_foreach(stack, i, file) {
+		git_vector_rforeach(&file->rules, j, match) {
+			if (git_attr_fnmatch__match(match, &path) == GIT_SUCCESS) {
+				*ignored = ((match->flags & GIT_ATTR_FNMATCH_NEGATIVE) == 0);
+				goto found;
+			}
+		}
+	}
+found:
+
+	return error;
+}
diff --git a/src/ignore.h b/src/ignore.h
new file mode 100644
index 000000000..2954445b5
--- /dev/null
+++ b/src/ignore.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2009-2011 the libgit2 contributors
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_ignore_h__
+#define INCLUDE_ignore_h__
+
+#include "repository.h"
+#include "vector.h"
+
+extern int git_ignore__for_path(git_repository *repo, const char *path, git_vector *stack);
+extern void git_ignore__free(git_vector *stack);
+extern int git_ignore__lookup(git_vector *stack, const char *path, int *ignored);
+
+#endif
diff --git a/src/path.c b/src/path.c
index f9663b7e5..03ebfe090 100644
--- a/src/path.c
+++ b/src/path.c
@@ -305,3 +305,47 @@ int git_path_fromurl(git_buf *local_path_out, const char *file_url)
 
 	return error;
 }
+
+int git_path_walk_up(
+	git_buf *path,
+	const char *ceiling,
+	int (*cb)(void *data, git_buf *),
+	void *data)
+{
+	int error = GIT_SUCCESS;
+	git_buf iter;
+	ssize_t stop = 0, scan;
+	char oldc = '\0';
+
+	assert(path && cb);
+
+	if (ceiling != NULL) {
+		if (git__prefixcmp(path->ptr, ceiling) == GIT_SUCCESS)
+			stop = (ssize_t)strlen(ceiling);
+		else
+			stop = path->size;
+	}
+	scan = path->size;
+
+	iter.ptr = path->ptr;
+	iter.size = path->size;
+	iter.asize = path->asize;
+
+	while (scan >= stop) {
+		if ((error = cb(data, &iter)) < GIT_SUCCESS)
+			break;
+		iter.ptr[scan] = oldc;
+		scan = git_buf_rfind_next(&iter, '/');
+		if (scan >= 0) {
+			scan++;
+			oldc = iter.ptr[scan];
+			iter.size = scan;
+			iter.ptr[scan] = '\0';
+		}
+	}
+
+	if (scan >= 0)
+		iter.ptr[scan] = oldc;
+
+	return error;
+}
diff --git a/src/path.h b/src/path.h
index c308c5bd4..e59c19ad9 100644
--- a/src/path.h
+++ b/src/path.h
@@ -77,4 +77,18 @@ GIT_INLINE(void) git_path_mkposix(char *path)
 extern int git__percent_decode(git_buf *decoded_out, const char *input);
 extern int git_path_fromurl(git_buf *local_path_out, const char *file_url);
 
+/**
+ * Invoke callback directory by directory up the path until the ceiling
+ * is reached (inclusive of a final call at the root_path).
+ *
+ * If the ceiling is NULL, this will walk all the way up to the root.
+ * If the ceiling is not a prefix of the path, the callback will be
+ * invoked a single time on the verbatim input path.  Returning anything
+ * other than GIT_SUCCESS from the callback function will stop the
+ * iteration and propogate the error to the caller.
+ */
+extern int git_path_walk_up(
+	git_buf *path, const char *ceiling,
+	int (*cb)(void *data, git_buf *), void *data);
+
 #endif
diff --git a/src/repository.h b/src/repository.h
index 82052158a..5274fc1d0 100644
--- a/src/repository.h
+++ b/src/repository.h
@@ -19,7 +19,7 @@
 #include "refs.h"
 #include "buffer.h"
 #include "odb.h"
-#include "attr_file.h"
+#include "attr.h"
 
 #define DOT_GIT ".git"
 #define GIT_DIR DOT_GIT "/"
diff --git a/src/status.c b/src/status.c
index 64be6ce29..3ead15a87 100644
--- a/src/status.c
+++ b/src/status.c
@@ -13,6 +13,7 @@
 #include "tree.h"
 #include "git2/status.h"
 #include "repository.h"
+#include "ignore.h"
 
 struct status_entry {
 	git_index_time mtime;
@@ -21,7 +22,7 @@ struct status_entry {
 	git_oid index_oid;
 	git_oid wt_oid;
 
-	unsigned int status_flags:6;
+	unsigned int status_flags;
 
 	char path[GIT_FLEX_ARRAY]; /* more */
 };
@@ -117,10 +118,30 @@ static int status_entry_update_flags(struct status_entry *e)
 	return GIT_SUCCESS;
 }
 
+static int status_entry_is_ignorable(struct status_entry *e)
+{
+	/* don't ignore files that exist in head or index already */
+	return (e->status_flags == GIT_STATUS_WT_NEW);
+}
+
+static int status_entry_update_ignore(struct status_entry *e, git_vector *ignores, const char *path)
+{
+	int error, ignored;
+
+	if ((error = git_ignore__lookup(ignores, path, &ignored)) == GIT_SUCCESS &&
+		ignored)
+		e->status_flags =
+			(e->status_flags & ~GIT_STATUS_WT_NEW) | GIT_STATUS_IGNORED;
+
+	return error;
+}
+
 struct status_st {
+	git_repository *repo;
 	git_vector *vector;
 	git_index *index;
 	git_tree *tree;
+	git_vector *ignores;
 
 	int workdir_path_len;
 	git_buf head_tree_relative_path;
@@ -210,9 +231,22 @@ static int process_folder(
 		}
 	}
 
-	if (full_path != NULL && path_type == GIT_STATUS_PATH_FOLDER)
-		error = alphasorted_futils_direach(full_path, dirent_cb, st);
-	else
+
+	if (full_path != NULL && path_type == GIT_STATUS_PATH_FOLDER) {
+		git_vector ignores = GIT_VECTOR_INIT, *old_ignores;
+
+		if ((error = git_ignore__for_path(st->repo,
+			full_path->ptr + st->workdir_path_len, &ignores)) == GIT_SUCCESS)
+		{
+			old_ignores = st->ignores;
+			st->ignores = &ignores;
+
+			error = alphasorted_futils_direach(full_path, dirent_cb, st);
+
+			git_ignore__free(st->ignores);
+			st->ignores = old_ignores;
+		}
+	} else
 		error = dirent_cb(st, NULL);
 
 	if (tree_entry_type == GIT_OBJ_TREE) {
@@ -232,6 +266,10 @@ static int store_if_changed(struct status_st *st, struct status_entry *e)
 	if ((error = status_entry_update_flags(e)) < GIT_SUCCESS)
 		return git__throw(error, "Failed to process the file '%s'. It doesn't exist in the workdir, in the HEAD nor in the index", e->path);
 
+	if (status_entry_is_ignorable(e) &&
+		(error = status_entry_update_ignore(e, st->ignores, e->path)) < GIT_SUCCESS)
+		return error;
+
 	if (e->status_flags == GIT_STATUS_CURRENT) {
 		git__free(e);
 		return GIT_SUCCESS;
@@ -240,7 +278,8 @@ static int store_if_changed(struct status_st *st, struct status_entry *e)
 	return git_vector_insert(st->vector, e);
 }
 
-static int determine_status(struct status_st *st,
+static int determine_status(
+	struct status_st *st,
 	int in_head, int in_index, int in_workdir,
 	const git_tree_entry *tree_entry,
 	const git_index_entry *index_entry,
@@ -274,8 +313,8 @@ static int determine_status(struct status_st *st,
 		}
 
 		if (in_workdir)
-			if ((error = status_entry_update_from_workdir(e, full_path->ptr
-)) < GIT_SUCCESS)
+			if ((error = status_entry_update_from_workdir(
+					 e, full_path->ptr)) < GIT_SUCCESS)
 				return error;	/* The callee has already set the error message */
 
 		return store_if_changed(st, e);
@@ -340,7 +379,6 @@ static int dirent_cb(void *state, git_buf *a)
 	int cmpma, cmpmi, cmpai, error;
 	const char *pm, *pa, *pi;
 	const char *m_name, *i_name, *a_name;
-
 	struct status_st *st = (struct status_st *)state;
 
 	path_type = path_type_from(a, st->is_dir);
@@ -372,7 +410,8 @@ static int dirent_cb(void *state, git_buf *a)
 
 			error = git_buf_lasterror(&st->head_tree_relative_path);
 			if (error < GIT_SUCCESS)
-				return git__rethrow(error, "An error occured while determining the status of '%s'", a->ptr);
+				return git__rethrow(error, "An error occured while "
+					"determining the status of '%s'", a->ptr);
 
 			m_name = st->head_tree_relative_path.ptr;
 		} else
@@ -388,7 +427,8 @@ static int dirent_cb(void *state, git_buf *a)
 		pa = ((cmpma >= 0) && (cmpai <= 0)) ? a_name : NULL;
 		pi = ((cmpmi >= 0) && (cmpai >= 0)) ? i_name : NULL;
 
-		if((error = determine_status(st, pm != NULL, pi != NULL, pa != NULL, m, entry, a, status_path(pm, pi, pa), path_type)) < GIT_SUCCESS)
+		if ((error = determine_status(st, pm != NULL, pi != NULL, pa != NULL,
+				m, entry, a, status_path(pm, pi, pa), path_type)) < GIT_SUCCESS)
 			return git__rethrow(error, "An error occured while determining the status of '%s'", a->ptr);
 
 		if ((pa != NULL) || (path_type == GIT_STATUS_PATH_FOLDER))
@@ -406,9 +446,12 @@ static int status_cmp(const void *a, const void *b)
 
 #define DEFAULT_SIZE 16
 
-int git_status_foreach(git_repository *repo, int (*callback)(const char *, unsigned int, void *), void *payload)
+int git_status_foreach(
+	git_repository *repo,
+	int (*callback)(const char *, unsigned int, void *),
+	void *payload)
 {
-	git_vector entries;
+	git_vector entries, ignores = GIT_VECTOR_INIT;
 	git_index *index = NULL;
 	git_buf temp_path = GIT_BUF_INIT;
 	struct status_st dirent_st = {0};
@@ -434,14 +477,16 @@ int git_status_foreach(git_repository *repo, int (*callback)(const char *, unsig
 
 	git_vector_init(&entries, DEFAULT_SIZE, status_cmp);
 
-	dirent_st.workdir_path_len = strlen(workdir);
-	dirent_st.tree_position = 0;
-	dirent_st.index_position = 0;
-	dirent_st.tree = tree;
-	dirent_st.index = index;
+	dirent_st.repo = repo;
 	dirent_st.vector = &entries;
+	dirent_st.index = index;
+	dirent_st.tree = tree;
+	dirent_st.ignores = &ignores;
+	dirent_st.workdir_path_len = strlen(workdir);
 	git_buf_init(&dirent_st.head_tree_relative_path, 0);
 	dirent_st.head_tree_relative_path_len = 0;
+	dirent_st.tree_position = 0;
+	dirent_st.index_position = 0;
 	dirent_st.is_dir = 1;
 
 	if (git_futils_isdir(workdir)) {
@@ -453,6 +498,10 @@ int git_status_foreach(git_repository *repo, int (*callback)(const char *, unsig
 
 	git_buf_sets(&temp_path, workdir);
 
+	error = git_ignore__for_path(repo, "", dirent_st.ignores);
+	if (error < GIT_SUCCESS)
+		goto exit;
+
 	error = alphasorted_futils_direach(
 		&temp_path, dirent_cb, &dirent_st);
 
@@ -461,7 +510,8 @@ int git_status_foreach(git_repository *repo, int (*callback)(const char *, unsig
 			"Failed to determine statuses. "
 			"An error occured while processing the working directory");
 
-	if ((error == GIT_SUCCESS) && ((error = dirent_cb(&dirent_st, NULL)) < GIT_SUCCESS))
+	if ((error == GIT_SUCCESS) &&
+		((error = dirent_cb(&dirent_st, NULL)) < GIT_SUCCESS))
 		error = git__rethrow(error,
 			"Failed to determine statuses. "
 			"An error occured while post-processing the HEAD tree and the index");
@@ -483,6 +533,7 @@ exit:
 	git_buf_free(&dirent_st.head_tree_relative_path);
 	git_buf_free(&temp_path);
 	git_vector_free(&entries);
+	git_vector_free(&ignores);
 	git_tree_free(tree);
 	return error;
 }
@@ -599,6 +650,18 @@ int git_status_file(unsigned int *status_flags, git_repository *repo, const char
 		goto cleanup;
 	}
 
+	if (status_entry_is_ignorable(e)) {
+		git_vector ignores = GIT_VECTOR_INIT;
+
+		if ((error = git_ignore__for_path(repo, path, &ignores)) == GIT_SUCCESS)
+			error = status_entry_update_ignore(e, &ignores, path);
+
+		git_ignore__free(&ignores);
+
+		if (error < GIT_SUCCESS)
+			goto cleanup;
+	}
+
 	*status_flags = e->status_flags;
 
 cleanup:
@@ -615,28 +678,15 @@ cleanup:
  *
  */
 
-struct alphasorted_dirent_info {
-	int is_dir;
-	char path[GIT_FLEX_ARRAY]; /* more */
-};
-
-static struct alphasorted_dirent_info *alphasorted_dirent_info_new(const git_buf *path)
+static char *alphasorted_dirent_info_new(const git_buf *path)
 {
-	int is_dir, size;
-	struct alphasorted_dirent_info *di;
-
-	is_dir = git_futils_isdir(path->ptr) == GIT_SUCCESS ? 1 : 0;
-	size   = sizeof(*di) + path->size + is_dir + 1;
-
-	di = git__calloc(size, 1);
-	if (di == NULL)
-		return NULL;
-
-	git_buf_copy_cstr(di->path, path->size + 1, path);
+	char *di = git__malloc(path->size + 2);
+	if (!di)
+		return di;
 
-	if (is_dir) {
-		di->is_dir = 1;
+	git_buf_copy_cstr(di, path->size + 1, path);
 
+	if (git_futils_isdir(path->ptr) == GIT_SUCCESS) {
 		/*
 		 * Append a forward slash to the name to force folders
 		 * to be ordered in a similar way than in a tree
@@ -644,23 +694,16 @@ static struct alphasorted_dirent_info *alphasorted_dirent_info_new(const git_buf
 		 * The file "subdir" should appear before the file "subdir.txt"
 		 * The folder "subdir" should appear after the file "subdir.txt"
 		 */
-		di->path[path->size] = '/';
+		di[path->size] = '/';
+		di[path->size + 1] = '\0';
 	}
 
 	return di;
 }
 
-static int alphasorted_dirent_info_cmp(const void *a, const void *b)
-{
-	struct alphasorted_dirent_info *stra = (struct alphasorted_dirent_info *)a;
-	struct alphasorted_dirent_info *strb = (struct alphasorted_dirent_info *)b;
-
-	return strcmp(stra->path, strb->path);
-}
-
 static int alphasorted_dirent_cb(void *state, git_buf *full_path)
 {
-	struct alphasorted_dirent_info *entry;
+	char *entry;
 	git_vector *entry_names;
 
 	entry_names = (git_vector *)state;
@@ -682,13 +725,13 @@ static int alphasorted_futils_direach(
 	int (*fn)(void *, git_buf *),
 	void *arg)
 {
-	struct alphasorted_dirent_info *entry;
+	char *entry;
 	git_vector entry_names;
 	unsigned int idx;
 	int error = GIT_SUCCESS;
 	git_buf entry_path = GIT_BUF_INIT;
 
-	if (git_vector_init(&entry_names, 16, alphasorted_dirent_info_cmp) < GIT_SUCCESS)
+	if (git_vector_init(&entry_names, 16, git__strcmp_cb) < GIT_SUCCESS)
 		return GIT_ENOMEM;
 
 	error = git_futils_direach(path, alphasorted_dirent_cb, &entry_names);
@@ -696,17 +739,18 @@ static int alphasorted_futils_direach(
 	git_vector_sort(&entry_names);
 
 	for (idx = 0; idx < entry_names.length; ++idx) {
-		entry = (struct alphasorted_dirent_info *)git_vector_get(&entry_names, idx);
+		entry = (char *)git_vector_get(&entry_names, idx);
 
 		/* We have to walk the entire vector even if there was an error,
 		 * in order to free up memory, but we stop making callbacks after
 		 * an error.
 		 */
 		if (error == GIT_SUCCESS)
-			error = git_buf_sets(&entry_path, entry->path);
+			error = git_buf_sets(&entry_path, entry);
 
 		if (error == GIT_SUCCESS) {
-			((struct status_st *)arg)->is_dir = entry->is_dir;
+			((struct status_st *)arg)->is_dir =
+				(entry[entry_path.size - 1] == '/');
 			error = fn(arg, &entry_path);
 		}
 
@@ -717,3 +761,18 @@ static int alphasorted_futils_direach(
 	git_vector_free(&entry_names);
 	return error;
 }
+
+
+int git_status_should_ignore(git_repository *repo, const char *path, int *ignored)
+{
+	int error;
+	git_vector ignores = GIT_VECTOR_INIT;
+
+	if ((error = git_ignore__for_path(repo, path, &ignores)) == GIT_SUCCESS)
+		error = git_ignore__lookup(&ignores, path, ignored);
+
+	git_ignore__free(&ignores);
+
+	return error;
+}
+
diff --git a/src/util.h b/src/util.h
index 2654e2de2..6c929cf0a 100644
--- a/src/util.h
+++ b/src/util.h
@@ -102,6 +102,13 @@ extern char *git__strtok(char **end, const char *sep);
 extern void git__strntolower(char *str, size_t len);
 extern void git__strtolower(char *str);
 
+GIT_INLINE(const char *) git__next_line(const char *s)
+{
+	while (*s && *s != '\n') s++;
+	while (*s == '\n' || *s == '\r') s++;
+	return s;
+}
+
 extern int git__fnmatch(const char *pattern, const char *name, int flags);
 
 extern void git__tsort(void **dst, size_t size, int (*cmp)(const void *, const void *));