Support $XDG_CONFIG_HOME for storing tup config

Author: cherryman

src/tup/option.c

@@ -47,6 +47,7 @@
 
 #define OPT_MAX 256
 
+static char xdg_config_home_loc[PATH_MAX];
 static char home_loc[PATH_MAX];
 
 static struct {
@@ -58,6 +59,7 @@ static struct {
 	{ .file = TUP_OPTIONS_FILE },
 	{ .file = home_loc },
 #ifndef _WIN32
+	{ .file = xdg_config_home_loc },
 	{ .file = "/etc/tup/options" },
 #endif
 };
@@ -67,6 +69,9 @@ static int parse_option_file(int x);
 static const char *cpu_number(void);
 static const char *stdout_isatty(void);
 static const char *get_console_width(void);
+#ifndef _WIN32
+static int init_xdg_config_home_loc(void);
+#endif
 static int init_home_loc(void);
 
 static struct option {
@@ -283,6 +288,11 @@ int tup_option_init(int argc, char **argv)
 			options[x].default_value = options[x].generator();
 	}
 
+#ifndef _WIN32
+	if (init_xdg_config_home_loc() < 0)
+		return -1;
+#endif
+
 	if(init_home_loc() < 0)
 		return -1;
 
@@ -535,6 +545,28 @@ static const char *stdout_isatty(void)
 	return buf;
 }
 
+#ifndef _WIN32
+static int init_xdg_config_home_loc(void) {
+	const char *base_dir;
+	const char *fmt_string;
+
+	if ((base_dir = getenv("XDG_CONFIG_HOME")) && *base_dir != '\0')
+		fmt_string = "%s/tup/options";
+	else if ((base_dir = getenv("HOME")))
+		fmt_string = "%s/.config/tup/options";
+	else
+		return 0;
+
+	if (snprintf(xdg_config_home_loc, sizeof(xdg_config_home_loc), fmt_string, base_dir)
+			>= (signed)sizeof(xdg_config_home_loc)) {
+		fprintf(stderr, "tup internal error: user-level options file string is too small.\n");
+		return -1;
+	}
+
+	return 0;
+}
+#endif
+
 static int init_home_loc(void)
 {
 #if defined(_WIN32)

test/t1007-tupoptions.sh

@@ -30,10 +30,34 @@ check()
 . ./tup.sh
 check_no_windows HOME environment variable
 
-# Override HOME so we can control ~/.tupoptions
+# Override HOME and XDG_CONFIG_HOME so we can control
+# the location of the options files.
+
+# Test ${XDG_CONFIG_HOME:-$HOME/.config}/tup/options
 export HOME=`pwd`
+export XDG_CONFIG_HOME=
 check keep_going 0
 
+mkdir -p "$HOME/.config/tup"
+cat > .config/tup/options << HERE
+[updater]
+num_jobs = 4
+keep_going = 1
+HERE
+check num_jobs 4
+check keep_going 1
+
+export XDG_CONFIG_HOME="$HOME/.alt_config"
+check keep_going 0
+
+mkdir -p "$XDG_CONFIG_HOME/tup"
+cat > "$XDG_CONFIG_HOME/tup/options" << HERE
+[updater]
+num_jobs = 5
+HERE
+check num_jobs 5
+
+# Test ~/.tupoptions, which overrides the previous file.
 cat > .tupoptions << HERE
 [updater]
 num_jobs = 2