Add --include option.

This allows config files to include other files, so you can e.g. split
style and behaviour options into different files.

6 files changed, 60 insertions, 1 deletions

diff --git a/completions/tofi b/completions/tofi
index 3ab6c32..0e21eed 100644
--- a/completions/tofi
+++ b/completions/tofi
@@ -8,6 +8,7 @@ _tofi()
 	words=(
 		--help
 		--config
+		--include
 		--output
 		--scale
 		--anchor
@@ -52,6 +53,8 @@ _tofi()
 	case "${prev}" in
 		--font)
 			;&
+		--include)
+			;&
 		--config|-c)
 			_filedir
 			return 0
diff --git a/doc/config b/doc/config
index e1e93a7..f95a367 100644
--- a/doc/config
+++ b/doc/config
@@ -144,3 +144,10 @@
 	# for a short time after launch. The only reason to use this option is
 	# performance on slow systems.
 	late-keyboard-init = false
+
+#
+### Inclusion
+#
+	# Configs can be split between multiple files, and then included
+	# within each other.
+	# include = /path/to/config
diff --git a/doc/tofi.5.md b/doc/tofi.5.md
index 8455667..b330278 100644
--- a/doc/tofi.5.md
+++ b/doc/tofi.5.md
@@ -20,6 +20,16 @@ case-insensitive, except where not possible (e.g. paths). Later options
 override earlier options, and command line options override config file
 options.
 
+# SPECIAL OPTIONS
+
+**include**=*path*
+
+> Include the contents of another config file. If *path* is a relative
+> path, it is interpreted as relative to this config file's path (or the
+> current directory if **--include** is passed on the command line).
+> Inclusion happens immediately, before the rest of the current file's
+> contents are parsed.
+
 # BEHAVIOUR OPTIONS
 
 **hide-cursor**=*true\|false*
diff --git a/doc/tofi.5.scd b/doc/tofi.5.scd
index 696b06e..e0faa2d 100644
--- a/doc/tofi.5.scd
+++ b/doc/tofi.5.scd
@@ -22,6 +22,14 @@ case-insensitive, except where not possible (e.g. paths). Later options
 override earlier options, and command line options override config file
 options.
 
+# SPECIAL OPTIONS
+
+*include*=_path_
+	Include the contents of another config file. If _path_ is a relative path,
+	it is interpreted as relative to this config file's path (or the current
+	directory if *--include* is passed on the command line). Inclusion happens
+	immediately, before the rest of the current file's contents are parsed.
+
 # BEHAVIOUR OPTIONS
 
 *hide-cursor*=_true|false_
diff --git a/src/config.c b/src/config.c
index 7e5fb6b..fb00fd6 100644
--- a/src/config.c
+++ b/src/config.c
@@ -1,5 +1,6 @@
 #include <ctype.h>
 #include <errno.h>
+#include <libgen.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -14,6 +15,9 @@
 /* Maximum number of config file errors before we give up */
 #define MAX_ERRORS 5
 
+/* Maximum inclusion recursion depth before we give up */
+#define MAX_RECURSION 32
+
 /* Anyone with a 10M config file is doing something very wrong */
 #define MAX_CONFIG_SIZE (10*1024*1024)
 
@@ -63,6 +67,17 @@ void config_load(struct tofi *tofi, const char *filename)
 		}
 		filename = default_filename;
 	}
+	/*
+	 * Track and limit recursion depth, so we don't overflow the stack if
+	 * a config file loop is created.
+	 */
+	static uint8_t recursion_depth = 0;
+	recursion_depth++;
+	if (recursion_depth > MAX_RECURSION) {
+		log_error("Refusing to load %s, recursion too deep (>%u layers).\n", filename, MAX_RECURSION);
+		recursion_depth--;
+		return;
+	}
 	char *config;
 	FILE *fp = fopen(filename, "rb");
 	if (!fp) {
@@ -205,6 +220,7 @@ CLEANUP_FILENAME:
 	if (default_filename) {
 		free(default_filename);
 	}
+	recursion_depth--;
 }
 
 char *strip(const char *str)
@@ -238,7 +254,20 @@ bool parse_option(struct tofi *tofi, const char *filename, size_t lineno, const
 {
 	bool err = false;
 	struct uint32_percent percent;
-	if (strcasecmp(option, "anchor") == 0) {
+	if (strcasecmp(option, "include") == 0) {
+		if (value[0] == '/') {
+			config_load(tofi, value);
+		} else {
+			char *tmp = xstrdup(filename);
+			char *dir = dirname(tmp);
+			size_t len = strlen(dir) + 1 + strlen(value) + 1;
+			char *config = xcalloc(len, 1);
+			snprintf(config, len, "%s/%s", dir, value);
+			config_load(tofi, config);
+			free(config);
+			free(tmp);
+		}
+	} else if (strcasecmp(option, "anchor") == 0) {
 		tofi->anchor = parse_anchor(filename, lineno, value, &err);
 	} else if (strcasecmp(option, "background-color") == 0) {
 		tofi->window.entry.background_color = parse_color(filename, lineno, value, &err);
diff --git a/src/main.c b/src/main.c
index 673bb9f..0a9cdf1 100644
--- a/src/main.c
+++ b/src/main.c
@@ -775,6 +775,7 @@ static void usage()
 "\n"
 "  -h, --help                           Print this message and exit.\n"
 "  -c, --config <path>                  Specify a config file.\n"
+"      --include <path>                 Include an additional config file.\n"
 "      --font <name|path>               Font to use.\n"
 "      --font-size <pt>                 Point size of text.\n"
 "      --background-color <color>       Color of the background.\n"
@@ -828,6 +829,7 @@ static void usage()
 const struct option long_options[] = {
 	{"help", no_argument, NULL, 'h'},
 	{"config", required_argument, NULL, 'c'},
+	{"include", required_argument, NULL, 0},
 	{"anchor", required_argument, NULL, 0},
 	{"background-color", required_argument, NULL, 0},
 	{"corner-radius", required_argument, NULL, 0},