Add global and system-wide gitattributes

Allow gitattributes to be set globally and system wide. This way, settings
for particular file types can be set in one place and apply for all user's
repositories.

The location of system-wide attributes file is $(prefix)/etc/gitattributes.
The location of the global file can be configured by setting
core.attributesfile.

Some parts of the code were copied from the implementation of the same
functionality in config.c.

Signed-off-by: Petr Onderka <gsvick@gmail.com>
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 51 insertions, 1 deletions

diff --git a/attr.c b/attr.c
index 8ba606c..6aff695 100644
--- a/attr.c
+++ b/attr.c
@@ -1,5 +1,6 @@
 #define NO_THE_INDEX_COMPATIBILITY_MACROS
 #include "cache.h"
+#include "exec_cmd.h"
 #include "attr.h"
 
 const char git_attr__true[] = "(builtin)true";
@@ -10,6 +11,8 @@ static const char git_attr__unknown[] = "(builtin)unknown";
 #define ATTR__UNSET NULL
 #define ATTR__UNKNOWN git_attr__unknown
 
+static const char *attributes_file;
+
 /*
  * The basic design decision here is that we are not going to have
  * insanely large number of attributes.
@@ -462,6 +465,32 @@ static void drop_attr_stack(void)
 	}
 }
 
+const char *git_etc_gitattributes(void)
+{
+	static const char *system_wide;
+	if (!system_wide)
+		system_wide = system_path(ETC_GITATTRIBUTES);
+	return system_wide;
+}
+
+int git_attr_system(void)
+{
+	return !git_env_bool("GIT_ATTR_NOSYSTEM", 0);
+}
+
+int git_attr_global(void)
+{
+	return !git_env_bool("GIT_ATTR_NOGLOBAL", 0);
+}
+
+static int git_attr_config(const char *var, const char *value, void *dummy)
+{
+	if (!strcmp(var, "core.attributesfile"))
+		return git_config_pathname(&attributes_file, var, value);
+
+	return 0;
+}
+
 static void bootstrap_attr_stack(void)
 {
 	if (!attr_stack) {
@@ -472,6 +501,25 @@ static void bootstrap_attr_stack(void)
 		elem->prev = attr_stack;
 		attr_stack = elem;
 
+		if (git_attr_system()) {
+			elem = read_attr_from_file(git_etc_gitattributes(), 1);
+			if (elem) {
+				elem->origin = NULL;
+				elem->prev = attr_stack;
+				attr_stack = elem;
+			}
+		}
+
+		git_config(git_attr_config, NULL);
+		if (git_attr_global() && attributes_file) {
+			elem = read_attr_from_file(attributes_file, 1);
+			if (elem) {
+				elem->origin = NULL;
+				elem->prev = attr_stack;
+				attr_stack = elem;
+			}
+		}
+
 		if (!is_bare_repository() || direction == GIT_ATTR_INDEX) {
 			elem = read_attr(GITATTRIBUTES_FILE, 1);
 			elem->origin = strdup("");
@@ -499,7 +547,9 @@ static void prepare_attr_stack(const char *path, int dirlen)
 
 	/*
 	 * At the bottom of the attribute stack is the built-in
-	 * set of attribute definitions.  Then, contents from
+	 * set of attribute definitions, followed by the contents
+	 * of $(prefix)/etc/gitattributes and a file specified by
+	 * core.attributesfile.  Then, contents from
 	 * .gitattribute files from directories closer to the
 	 * root to the ones in deeper directories are pushed
 	 * to the stack.  Finally, at the very top of the stack