Resolve paths relative to XDG config. paths

This should make the programs an awful lot less painful to set up.

3 files changed, 131 insertions, 100 deletions

diff --git a/src/common.c b/src/common.c
index 2907159..8f7ffd1 100644
--- a/src/common.c
+++ b/src/common.c
@@ -1359,6 +1359,58 @@ get_xdg_home_dir (struct str *output, const char *var, const char *def)
 	}
 }
 
+static void
+get_xdg_config_dirs (struct str_vector *out)
+{
+	struct str config_home;
+	str_init (&config_home);
+	get_xdg_home_dir (&config_home, "XDG_CONFIG_HOME", ".config");
+	str_vector_add (out, config_home.str);
+	str_free (&config_home);
+
+	const char *xdg_config_dirs;
+	if ((xdg_config_dirs = getenv ("XDG_CONFIG_DIRS")))
+		split_str_ignore_empty (xdg_config_dirs, ':', out);
+}
+
+static char *
+resolve_config_filename (const char *filename)
+{
+	// Absolute path is absolute
+	if (*filename == '/')
+		return xstrdup (filename);
+
+	struct str_vector paths;
+	str_vector_init (&paths);
+	get_xdg_config_dirs (&paths);
+
+	struct str file;
+	str_init (&file);
+
+	char *result = NULL;
+	for (unsigned i = 0; i < paths.len; i++)
+	{
+		// As per spec, relative paths are ignored
+		if (*paths.vector[i] != '/')
+			continue;
+
+		str_reset (&file);
+		str_append_printf (&file, "%s/" PROGRAM_NAME "/%s",
+			paths.vector[i], filename);
+
+		struct stat st;
+		if (!stat (file.str, &st))
+		{
+			result = str_steal (&file);
+			break;
+		}
+	}
+
+	str_vector_free (&paths);
+	str_free (&file);
+	return result;
+}
+
 static size_t io_error_domain_tag;
 #define IO_ERROR (error_resolve_domain (&io_error_domain_tag))
 
@@ -1729,45 +1781,6 @@ struct config_item
 	const char *description;
 };
 
-static FILE *
-get_config_file (void)
-{
-	struct str_vector paths;
-	struct str config_home, file;
-	const char *xdg_config_dirs;
-	unsigned i;
-	FILE *fp = NULL;
-
-	str_vector_init (&paths);
-
-	str_init (&config_home);
-	get_xdg_home_dir (&config_home, "XDG_CONFIG_HOME", ".config");
-	str_vector_add (&paths, config_home.str);
-	str_free (&config_home);
-
-	if ((xdg_config_dirs = getenv ("XDG_CONFIG_DIRS")))
-		split_str_ignore_empty (xdg_config_dirs, ':', &paths);
-
-	str_init (&file);
-	for (i = 0; i < paths.len; i++)
-	{
-		// As per spec, relative paths are ignored
-		if (*paths.vector[i] != '/')
-			continue;
-
-		str_reset (&file);
-		str_append (&file, paths.vector[i]);
-		str_append (&file, "/" PROGRAM_NAME "/" PROGRAM_NAME ".conf");
-
-		if ((fp = fopen (file.str, "r")))
-			break;
-	}
-
-	str_free (&file);
-	str_vector_free (&paths);
-	return fp;
-}
-
 static void
 load_config_defaults (struct str_map *config, const struct config_item *table)
 {
@@ -1781,16 +1794,23 @@ load_config_defaults (struct str_map *config, const struct config_item *table)
 static bool
 read_config_file (struct str_map *config, struct error **e)
 {
-	struct str line;
-	FILE *fp = get_config_file ();
-	unsigned line_no = 0;
-	bool errors = false;
+	char *filename = resolve_config_filename (PROGRAM_NAME ".conf");
+	if (!filename)
+		return true;
 
+	FILE *fp = fopen (filename, "r");
 	if (!fp)
-		return true;
+	{
+		error_set (e, IO_ERROR, IO_ERROR_FAILED,
+			"could not open `%s' for reading: %s", filename, strerror (errno));
+		return false;
+	}
 
+	struct str line;
 	str_init (&line);
-	for (line_no = 1; read_line (fp, &line); line_no++)
+
+	bool errors = false;
+	for (unsigned line_no = 1; read_line (fp, &line); line_no++)
 	{
 		char *start = line.str;
 		if (*start == '#')
@@ -1894,3 +1914,25 @@ error:
 	return NULL;
 
 }
+
+static void
+call_write_default_config (const char *hint, const struct config_item *table)
+{
+	static const char *prolog =
+	"# " PROGRAM_NAME " " PROGRAM_VERSION " configuration file\n"
+	"#\n"
+	"# Relative paths are searched for in ${XDG_CONFIG_HOME:-~/.config}\n"
+	"# /" PROGRAM_NAME " as well as in $XDG_CONFIG_DIRS/" PROGRAM_NAME "\n"
+	"\n";
+
+	struct error *e = NULL;
+	char *filename = write_default_config (hint, prolog, table, &e);
+	if (!filename)
+	{
+		print_fatal ("%s", e->message);
+		error_free (e);
+		exit (EXIT_FAILURE);
+	}
+	print_status ("configuration written to `%s'", filename);
+	free (filename);
+}
diff --git a/src/kike.c b/src/kike.c
index de4ae36..04dd4fc 100644
--- a/src/kike.c
+++ b/src/kike.c
@@ -1073,15 +1073,20 @@ irc_initialize_ssl (struct server_context *ctx)
 		return true;
 
 	if (!ssl_cert)
-	{
 		print_error ("no SSL certificate set");
-		return false;
-	}
 	if (!ssl_key)
-	{
 		print_error ("no SSL private key set");
+	if (!ssl_cert || !ssl_key)
+		return false;
+
+	char *cert_path = resolve_config_filename (ssl_cert);
+	char *key_path = resolve_config_filename (ssl_key);
+	if (!cert_path)
+		print_error ("%s: %s", "cannot open file", ssl_cert);
+	if (!key_path)
+		print_error ("%s: %s", "cannot open file", ssl_key);
+	if (!cert_path || !key_path)
 		return false;
-	}
 
 	ctx->ssl_ctx = SSL_CTX_new (SSLv23_server_method ());
 	if (!ctx->ssl_ctx)
@@ -1091,13 +1096,13 @@ irc_initialize_ssl (struct server_context *ctx)
 	// XXX: maybe we should call SSL_CTX_set_options() for some workarounds
 
 	// XXX: perhaps we should read the files ourselves for better messages
-	if (!SSL_CTX_use_certificate_chain_file (ctx->ssl_ctx, ssl_cert))
+	if (!SSL_CTX_use_certificate_chain_file (ctx->ssl_ctx, cert_path))
 	{
 		print_error ("%s: %s", "setting the SSL client certificate failed",
 			ERR_error_string (ERR_get_error (), NULL));
 		goto error_ssl_2;
 	}
-	if (!SSL_CTX_use_PrivateKey_file (ctx->ssl_ctx, ssl_key, SSL_FILETYPE_PEM))
+	if (!SSL_CTX_use_PrivateKey_file (ctx->ssl_ctx, key_path, SSL_FILETYPE_PEM))
 	{
 		print_error ("%s: %s", "setting the SSL private key failed",
 			ERR_error_string (ERR_get_error (), NULL));
@@ -1132,7 +1137,16 @@ irc_initialize_catalog (struct server_context *ctx, struct error **e)
 	if (!catalog)
 		return true;
 
-	ctx->catalog = catopen (catalog, NL_CAT_LOCALE);
+	char *path = resolve_config_filename (catalog);
+	if (!path)
+	{
+		error_set (e, IO_ERROR, IO_ERROR_FAILED, "%s: %s",
+			"cannot open file", catalog);
+		return false;
+	}
+	ctx->catalog = catopen (path, NL_CAT_LOCALE);
+	free (path);
+
 	if (ctx->catalog == (nl_catd) -1)
 	{
 		error_set (e, IO_ERROR, IO_ERROR_FAILED, "%s: %s",
@@ -1150,11 +1164,20 @@ irc_initialize_motd (struct server_context *ctx, struct error **e)
 	if (!motd)
 		return true;
 
-	FILE *fp = fopen (motd, "r");
+	char *path = resolve_config_filename (motd);
+	if (!path)
+	{
+		error_set (e, IO_ERROR, IO_ERROR_FAILED, "%s: %s",
+			"cannot open file", motd);
+		return false;
+	}
+	FILE *fp = fopen (path, "r");
+	free (path);
+
 	if (!fp)
 	{
-		error_set (e, IO_ERROR, IO_ERROR_FAILED,
-			"%s: %s", "failed reading the MOTD file", strerror (errno));
+		error_set (e, IO_ERROR, IO_ERROR_FAILED, "%s: %s",
+			"failed reading the MOTD file", strerror (errno));
 		return false;
 	}
 
@@ -1312,25 +1335,6 @@ print_usage (const char *program_name)
 		program_name);
 }
 
-static void
-call_write_default_config (const char *hint)
-{
-	static const char *prolog =
-		"# " PROGRAM_NAME " " PROGRAM_VERSION " configuration file\n"
-		"\n";
-
-	struct error *e = NULL;
-	char *filename = write_default_config (hint, prolog, g_config_table, &e);
-	if (!filename)
-	{
-		print_fatal ("%s", e->message);
-		error_free (e);
-		exit (EXIT_FAILURE);
-	}
-	print_status ("configuration written to `%s'", filename);
-	free (filename);
-}
-
 int
 main (int argc, char *argv[])
 {
@@ -1365,7 +1369,7 @@ main (int argc, char *argv[])
 			printf (PROGRAM_NAME " " PROGRAM_VERSION "\n");
 			exit (EXIT_SUCCESS);
 		case 'w':
-			call_write_default_config (optarg);
+			call_write_default_config (optarg, g_config_table);
 			exit (EXIT_SUCCESS);
 		default:
 			print_fatal ("error in options");
diff --git a/src/zyklonb.c b/src/zyklonb.c
index 1c7f6ae..de4e3ac 100644
--- a/src/zyklonb.c
+++ b/src/zyklonb.c
@@ -277,12 +277,16 @@ irc_initialize_ssl (struct bot_context *ctx, struct error **e)
 		goto error_ssl_2;
 
 	const char *ssl_cert = str_map_find (&ctx->config, "ssl_cert");
-	if (ssl_cert
-	 && !SSL_use_certificate_file (ctx->ssl, ssl_cert, SSL_FILETYPE_PEM))
+	if (ssl_cert)
 	{
+		char *path = resolve_config_filename (ssl_cert);
+		if (!path)
+			print_error ("%s: %s", "cannot open file", ssl_cert);
 		// XXX: perhaps we should read the file ourselves for better messages
-		print_error ("%s: %s", "setting the SSL client certificate failed",
-			ERR_error_string (ERR_get_error (), NULL));
+		else if (!SSL_use_certificate_file (ctx->ssl, path, SSL_FILETYPE_PEM))
+			print_error ("%s: %s", "setting the SSL client certificate failed",
+				ERR_error_string (ERR_get_error (), NULL));
+		free (path);
 	}
 
 	SSL_set_connect_state (ctx->ssl);
@@ -1686,25 +1690,6 @@ print_usage (const char *program_name)
 		program_name);
 }
 
-static void
-call_write_default_config (const char *hint)
-{
-	static const char *prolog =
-		"# " PROGRAM_NAME " " PROGRAM_VERSION " configuration file\n"
-		"\n";
-
-	struct error *e = NULL;
-	char *filename = write_default_config (hint, prolog, g_config_table, &e);
-	if (!filename)
-	{
-		print_fatal ("%s", e->message);
-		error_free (e);
-		exit (EXIT_FAILURE);
-	}
-	print_status ("configuration written to `%s'", filename);
-	free (filename);
-}
-
 int
 main (int argc, char *argv[])
 {
@@ -1741,7 +1726,7 @@ main (int argc, char *argv[])
 			printf (PROGRAM_NAME " " PROGRAM_VERSION "\n");
 			exit (EXIT_SUCCESS);
 		case 'w':
-			call_write_default_config (optarg);
+			call_write_default_config (optarg, g_config_table);
 			exit (EXIT_SUCCESS);
 		default:
 			print_fatal ("error in options");