Import xdg.c from catgirl

6 files changed, 169 insertions, 49 deletions

diff --git a/Makefile b/Makefile
index 19dc3b1..46796b7 100644
--- a/Makefile
+++ b/Makefile
@@ -12,7 +12,7 @@ RCS  = rc.d/litterbox
 -include config.mk
 
 FORMATS = generic catgirl irc textual
-OBJS.litterbox = litterbox.o config.o
+OBJS.litterbox = litterbox.o config.o xdg.o
 
 dev: tags all test
 
diff --git a/README.7 b/README.7
index 16943a9..5a0f743 100644
--- a/README.7
+++ b/README.7
@@ -1,4 +1,4 @@
-.Dd August 10, 2020
+.Dd August 20, 2020
 .Dt README 7
 .Os "Causal Agency"
 .
@@ -88,6 +88,8 @@ log file processing
 .It Pa config.c
 .Xr getopt_long 3 Ns -integrated
 configuration parsing
+.It Pa xdg.c
+XDG base directories
 .It Pa rc.d/
 .Fx
 .Xr rc 8
diff --git a/config.c b/config.c
index 60359d8..b8b4efa 100644
--- a/config.c
+++ b/config.c
@@ -33,43 +33,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-#define CONFIG_DIR "litterbox"
-
-static FILE *find(const char *path, const char *mode) {
-	if (path[0] == '/' || path[0] == '.') goto local;
-
-	const char *home = getenv("HOME");
-	const char *configHome = getenv("XDG_CONFIG_HOME");
-	const char *configDirs = getenv("XDG_CONFIG_DIRS");
-
-	char buf[PATH_MAX];
-	if (configHome) {
-		snprintf(buf, sizeof(buf), "%s/" CONFIG_DIR "/%s", configHome, path);
-	} else {
-		if (!home) goto local;
-		snprintf(buf, sizeof(buf), "%s/.config/" CONFIG_DIR "/%s", home, path);
-	}
-	FILE *file = fopen(buf, mode);
-	if (file) return file;
-	if (errno != ENOENT) return NULL;
-
-	if (!configDirs) configDirs = "/etc/xdg";
-	while (*configDirs) {
-		size_t len = strcspn(configDirs, ":");
-		snprintf(
-			buf, sizeof(buf), "%.*s/" CONFIG_DIR "/%s",
-			(int)len, configDirs, path
-		);
-		file = fopen(buf, mode);
-		if (file) return file;
-		if (errno != ENOENT) return NULL;
-		configDirs += len;
-		if (*configDirs) configDirs++;
-	}
-
-local:
-	return fopen(path, mode);
-}
+#include "database.h"
 
 #define WS "\t "
 
@@ -102,11 +66,8 @@ int getopt_config(
 			if (optind < argc) {
 				num = 0;
 				path = argv[optind++];
-				file = find(path, "r");
-				if (!file) {
-					warn("%s", path);
-					return clean('?');
-				}
+				file = configOpen(path, "r");
+				if (!file) return clean('?');
 			} else {
 				return clean(-1);
 			}
diff --git a/database.h b/database.h
index fbef0bb..d2db1f0 100644
--- a/database.h
+++ b/database.h
@@ -27,6 +27,7 @@
 
 #include <err.h>
 #include <errno.h>
+#include <getopt.h>
 #include <limits.h>
 #include <sqlite3.h>
 #include <stdbool.h>
@@ -40,6 +41,20 @@
 #define SQL(...) #__VA_ARGS__
 #define ARRAY_LEN(a) (sizeof(a) / sizeof((a)[0]))
 
+const char *configPath(
+	char *buf, size_t cap, const char **dirs, const char *path
+);
+const char *dataPath(
+	char *buf, size_t cap, const char **dirs, const char *path
+);
+FILE *configOpen(const char *path, const char *mode);
+FILE *dataOpen(const char *path, const char *mode);
+void dataMkdir(const char *path);
+int getopt_config(
+	int argc, char *const *argv, const char *optstring,
+	const struct option *longopts, int *longindex
+);
+
 #define DATABASE_PATH "litterbox/litterbox.sqlite"
 
 enum { DatabaseVersion = 5 };
diff --git a/litterbox.c b/litterbox.c
index 2dee87d..ffd838c 100644
--- a/litterbox.c
+++ b/litterbox.c
@@ -39,11 +39,6 @@
 
 #include "database.h"
 
-int getopt_config(
-	int argc, char *const *argv, const char *optstring,
-	const struct option *longopts, int *longindex
-);
-
 static const char *host;
 static const char *port = "6697";
 static struct tls *client;
diff --git a/xdg.c b/xdg.c
new file mode 100644
index 0000000..ded02af
--- /dev/null
+++ b/xdg.c
@@ -0,0 +1,147 @@
+/* Copyright (C) 2019, 2020  C. McEnroe <june@causal.agency>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * Additional permission under GNU GPL version 3 section 7:
+ *
+ * If you modify this Program, or any covered work, by linking or
+ * combining it with OpenSSL (or a modified version of that library),
+ * containing parts covered by the terms of the OpenSSL License and the
+ * original SSLeay license, the licensors of this Program grant you
+ * additional permission to convey the resulting work. Corresponding
+ * Source for a non-source form of such a combination shall include the
+ * source code for the parts of OpenSSL used as well as that of the
+ * covered work.
+ */
+
+#include <err.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#define SUBDIR "litterbox"
+
+struct Base {
+	const char *envHome;
+	const char *envDirs;
+	const char *defHome;
+	const char *defDirs;
+};
+
+static const struct Base Config = {
+	.envHome = "XDG_CONFIG_HOME",
+	.envDirs = "XDG_CONFIG_DIRS",
+	.defHome = ".config",
+	.defDirs = "/etc/xdg",
+};
+
+static const struct Base Data = {
+	.envHome = "XDG_DATA_HOME",
+	.envDirs = "XDG_DATA_DIRS",
+	.defHome = ".local/share",
+	.defDirs = "/usr/local/share:/usr/share",
+};
+
+static const char *basePath(
+	struct Base base,
+	char *buf, size_t cap, const char **dirs, const char *path
+) {
+	if (*dirs) {
+		if (!**dirs) return NULL;
+		size_t len = strcspn(*dirs, ":");
+		snprintf(buf, cap, "%.*s/" SUBDIR "/%s", (int)len, *dirs, path);
+		*dirs += len;
+		if (**dirs) *dirs += 1;
+		return buf;
+	}
+
+	if (path[0] == '/' || path[0] == '.') {
+		*dirs = "";
+		return path;
+	}
+
+	*dirs = getenv(base.envDirs);
+	if (!*dirs) *dirs = base.defDirs;
+
+	const char *home = getenv("HOME");
+	const char *baseHome = getenv(base.envHome);
+	if (baseHome) {
+		snprintf(buf, cap, "%s/" SUBDIR "/%s", baseHome, path);
+	} else {
+		if (!home) return NULL;
+		snprintf(buf, cap, "%s/%s/" SUBDIR "/%s", home, base.defHome, path);
+	}
+	return buf;
+}
+
+const char *
+configPath(char *buf, size_t cap, const char **dirs, const char *path) {
+	return basePath(Config, buf, cap, dirs, path);
+}
+
+const char *
+dataPath(char *buf, size_t cap, const char **dirs, const char *path) {
+	return basePath(Data, buf, cap, dirs, path);
+}
+
+FILE *configOpen(const char *path, const char *mode) {
+	const char *abs;
+	char buf[PATH_MAX];
+	const char *dirs = NULL;
+	while (NULL != (abs = configPath(buf, sizeof(buf), &dirs, path))) {
+		FILE *file = fopen(abs, mode);
+		if (file) return file;
+		if (errno != ENOENT) warn("%s", abs);
+	}
+	FILE *file = fopen(path, mode);
+	if (!file) warn("%s", path);
+	return file;
+}
+
+void dataMkdir(const char *path) {
+	char buf[PATH_MAX];
+	const char *dirs = NULL;
+	const char *abs = dataPath(buf, sizeof(buf), &dirs, path);
+	int error = mkdir(abs, S_IRWXU);
+	if (error && errno != EEXIST) warn("%s", abs);
+}
+
+FILE *dataOpen(const char *path, const char *mode) {
+	const char *abs;
+	char buf[PATH_MAX];
+	const char *dirs = NULL;
+	while (NULL != (abs = dataPath(buf, sizeof(buf), &dirs, path))) {
+		FILE *file = fopen(abs, mode);
+		if (file) return file;
+		if (errno != ENOENT) warn("%s", abs);
+	}
+
+	if (mode[0] != 'r') {
+		dirs = NULL;
+		abs = dataPath(buf, sizeof(buf), &dirs, path);
+		if (!abs) return NULL;
+
+		dataMkdir("");
+		FILE *file = fopen(abs, mode);
+		if (!file) warn("%s", abs);
+		return file;
+	}
+
+	FILE *file = fopen(path, mode);
+	if (!file) warn("%s", path);
+	return file;
+}