git config: trivial rename in preparation for parseopt

Essentially this replaces 'file' with 'prefix' in the cases where the
variable is used as a prefix, which is consistent with other git
commands.

When using the --list option general errors where not properly reported,
only errors related with the 'file'. Now they are reported, and 'file'
is irrelevant.

That reduces the rest of 'file' usage to nothing, therefore now only
'prefix' remains.

Suggested by Johannes Schindelin.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-config.c

@@ -178,6 +178,7 @@ static char *normalize_value(const char *key, const char *value)
 
 static int get_color_found;
 static const char *get_color_slot;
+static const char *get_colorbool_slot;
 static char parsed_color[COLOR_MAXLEN];
 
 static int git_get_color_config(const char *var, const char *value, void *cb)
@@ -231,7 +232,7 @@ static int get_diff_color_found;
 static int git_get_colorbool_config(const char *var, const char *value,
 		void *cb)
 {
-	if (!strcmp(var, get_color_slot)) {
+	if (!strcmp(var, get_colorbool_slot)) {
 		get_colorbool_found =
 			git_config_colorbool(var, value, stdout_is_tty);
 	}
@@ -263,11 +264,11 @@ static int get_colorbool(int argc, const char **argv)
 		usage(git_config_set_usage);
 	get_colorbool_found = -1;
 	get_diff_color_found = -1;
-	get_color_slot = argv[0];
+	get_colorbool_slot = argv[0];
 	git_config(git_get_colorbool_config, NULL);
 
 	if (get_colorbool_found < 0) {
-		if (!strcmp(get_color_slot, "color.diff"))
+		if (!strcmp(get_colorbool_slot, "color.diff"))
 			get_colorbool_found = get_diff_color_found;
 		if (get_colorbool_found < 0)
 			get_colorbool_found = git_use_color_default;
@@ -281,11 +282,11 @@ static int get_colorbool(int argc, const char **argv)
 	}
 }
 
-int cmd_config(int argc, const char **argv, const char *prefix)
+int cmd_config(int argc, const char **argv, const char *unused_prefix)
 {
 	int nongit;
 	char *value;
-	const char *file = setup_git_directory_gently(&nongit);
+	const char *prefix = setup_git_directory_gently(&nongit);
 
 	config_exclusive_filename = getenv(CONFIG_ENVIRONMENT);
 
@@ -299,10 +300,13 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 		else if (!strcmp(argv[1], "--list") || !strcmp(argv[1], "-l")) {
 			if (argc != 2)
 				usage(git_config_set_usage);
-			if (git_config(show_all_config, NULL) < 0 &&
-					file && errno)
-				die("unable to read config file %s: %s", file,
-				    strerror(errno));
+			if (git_config(show_all_config, NULL) < 0) {
+				if (config_exclusive_filename)
+					die("unable to read config file %s: %s",
+					    config_exclusive_filename, strerror(errno));
+				else
+					die("error processing config file(s)");
+			}
 			return 0;
 		}
 		else if (!strcmp(argv[1], "--global")) {
@@ -319,12 +323,12 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 		else if (!strcmp(argv[1], "--file") || !strcmp(argv[1], "-f")) {
 			if (argc < 3)
 				usage(git_config_set_usage);
-			if (!is_absolute_path(argv[2]) && file)
-				file = prefix_filename(file, strlen(file),
-						       argv[2]);
+			if (!is_absolute_path(argv[2]) && prefix)
+				config_exclusive_filename = prefix_filename(prefix,
+									    strlen(prefix),
+									    argv[2]);
 			else
-				file = argv[2];
-			config_exclusive_filename = file;
+				config_exclusive_filename = argv[2];
 			argc--;
 			argv++;
 		}