refactoring widget library

Change-Id: I9662573ed677d34daa393f0e207a4cd4a822f8ad
Signed-off-by: José Bollo <jose.bollo@iot.bzh>

1 files changed, 268 insertions, 0 deletions

diff --git a/src/wgt.c b/src/wgt.c
new file mode 100644
index 0000000..dd889d5
--- /dev/null
+++ b/src/wgt.c
@@ -0,0 +1,268 @@
+/*
+ Copyright 2015 IoT.bzh
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <assert.h>
+#include <limits.h>
+#include <string.h>
+#include <ctype.h>
+
+
+#include "wgt.h"
+
+struct wgt {
+	int rootfd;
+	int nrlocales;
+	char **locales;
+};
+
+static int validsubpath(const char *subpath)
+{
+	int l = 0, i = 0;
+	if (subpath[i] == '/')
+		return 0;
+	while(subpath[i]) {
+		switch(subpath[i++]) {
+		case '.':
+			if (!subpath[i])
+				break;
+			if (subpath[i] == '/') {
+				i++;
+				break;
+			}
+			if (subpath[i++] == '.') {
+				if (!subpath[i]) {
+					l--;
+					break;
+				}
+				if (subpath[i++] == '/') {
+					l--;
+					break;
+				}
+			}
+		default:
+			while(subpath[i] && subpath[i] != '/')
+				i++;
+			l++;
+		case '/':
+			break;
+		}
+	}
+	return l >= 0;
+}
+
+struct wgt *wgt_create()
+{
+	struct wgt *wgt = malloc(sizeof * wgt);
+	if (wgt) {
+		wgt->rootfd = -1;
+		wgt->nrlocales = 0;
+		wgt->locales = NULL;
+	}
+	return wgt;
+}
+
+void wgt_disconnect(struct wgt *wgt)
+{
+	assert(wgt);
+	if (wgt->rootfd >= 0)
+		close(wgt->rootfd);
+	wgt->rootfd = -1;
+}
+
+void wgt_locales_reset(struct wgt *wgt)
+{
+	assert(wgt);
+	while(wgt->nrlocales)
+		free(wgt->locales[--wgt->nrlocales]);
+}
+
+void wgt_destroy(struct wgt *wgt)
+{
+	if (wgt) {
+		wgt_disconnect(wgt);
+		wgt_locales_reset(wgt);
+		free(wgt->locales);
+		free(wgt);
+	}
+}
+
+int wgt_connect(struct wgt *wgt, const char *pathname)
+{
+	int rfd;
+
+	assert(wgt);
+
+	rfd = AT_FDCWD;
+	if (pathname) {
+		rfd = openat(rfd, pathname, O_PATH|O_DIRECTORY);
+		if (rfd < 0)
+			return rfd;
+	}
+	if (wgt->rootfd >= 0)
+		close(wgt->rootfd);
+	wgt->rootfd = rfd;
+	return 0;
+}
+
+int wgt_is_connected(struct wgt *wgt)
+{
+	assert(wgt);
+	return wgt->rootfd != -1;
+}
+
+int wgt_has(struct wgt *wgt, const char *filename)
+{
+	assert(wgt);
+	assert(wgt_is_connected(wgt));
+	if (!validsubpath(filename)) {
+		errno = EINVAL;
+		return -1;
+	}
+	return 0 == faccessat(wgt->rootfd, filename, F_OK, 0);
+}
+
+int wgt_open_read(struct wgt *wgt, const char *filename)
+{
+	assert(wgt);
+	assert(wgt_is_connected(wgt));
+	if (!validsubpath(filename)) {
+		errno = EINVAL;
+		return -1;
+	}
+	return openat(wgt->rootfd, filename, O_RDONLY);
+}
+
+static int locadd(struct wgt *wgt, const char *locstr, int length)
+{
+	int i;
+	char *item, **ptr;
+
+	item = strndup(locstr, length);
+	if (item != NULL) {
+		for (i = 0 ; item[i] ; i++)
+			item[i] = tolower(item[i]);
+		for (i = 0 ; i < wgt->nrlocales ; i++)
+			if (!strcmp(item, wgt->locales[i])) {
+				free(item);
+				return 0;
+			}
+
+		ptr = realloc(wgt->locales, (1 + wgt->nrlocales) * sizeof(wgt->locales[0]));
+		if (ptr) {
+			wgt->locales = ptr;
+			wgt->locales[wgt->nrlocales++] = item;
+			return 0;
+		}
+		free(item);
+	}
+	errno = ENOMEM;
+	return -1;
+}
+
+int wgt_locales_add(struct wgt *wgt, const char *locstr)
+{
+	const char *stop, *next;
+	assert(wgt);
+	while (*locstr) {
+		stop = strchrnul(locstr, ',');
+		next = stop + !!*stop;
+		while (locstr != stop) {
+			if (locadd(wgt, locstr, stop - locstr))
+				return -1;
+			do { stop--; } while(stop > locstr && *stop != '-');
+		}
+		locstr = next;
+	}
+	return 0;
+}
+
+int wgt_locales_score(struct wgt *wgt, const char *lang)
+{
+	int i;
+
+	assert(wgt);
+	if (lang)
+		for (i = 0 ; i < wgt->nrlocales ; i++)
+			if (!strcasecmp(lang, wgt->locales[i]))
+				return i;
+
+	return INT_MAX;
+}
+
+static const char *localize(struct wgt *wgt, const char *filename, char path[PATH_MAX])
+{
+	int i;
+
+	if (!validsubpath(filename)) {
+		errno = EINVAL;
+		return NULL;
+	}
+	for (i = 0 ; i < wgt->nrlocales ; i++) {
+		if (snprintf(path, PATH_MAX, "locales/%s/%s", wgt->locales[i], filename) >= PATH_MAX) {
+			errno = EINVAL;
+			return NULL;
+		}
+		if (0 == faccessat(wgt->rootfd, path, F_OK, 0))
+			return path;
+	}
+	if (0 == faccessat(wgt->rootfd, filename, F_OK, 0))
+		return filename;
+	errno = ENOENT;
+	return NULL;
+}
+
+char *wgt_locales_locate(struct wgt *wgt, const char *filename)
+{
+	char path[PATH_MAX];
+	char * result;
+	const char * loc;
+
+	assert(wgt);
+	assert(wgt_is_connected(wgt));
+	loc = localize(wgt, filename, path);
+	if (!loc)
+		result = NULL;
+	else {
+		result = strdup(loc);
+		if (!result)
+			errno = ENOMEM;
+	}
+	return result;
+}
+
+
+int wgt_locales_open_read(struct wgt *wgt, const char *filename)
+{
+	char path[PATH_MAX];
+	const char *loc;
+
+	assert(wgt);
+	assert(wgt_is_connected(wgt));
+	loc = localize(wgt, filename, path);
+	if (!loc)
+		return -1;
+
+	return openat(wgt->rootfd, loc, O_RDONLY);
+}
+
+