From bdcb813ee66a0b96c38bd04dbb2ad6a9e99c5fc9 Mon Sep 17 00:00:00 2001
From: topjohnwu <topjohnwu@gmail.com>
Date: Sat, 15 Apr 2017 18:33:16 +0800
Subject: [PATCH] Add block rw support

---
 jni/daemon/daemon.c |  3 +++
 jni/utils/misc.c    | 32 ++++++++++++++++++++++++++++++--
 jni/utils/utils.h   |  1 +
 3 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/jni/daemon/daemon.c b/jni/daemon/daemon.c
index 7a8241ff3..8868b3a37 100644
--- a/jni/daemon/daemon.c
+++ b/jni/daemon/daemon.c
@@ -104,6 +104,9 @@ void start_daemon() {
 	// Start log monitor
 	monitor_logs();
 
+	// Unlock all blocks for rw
+	unlock_blocks();
+
 	// Loop forever to listen to requests
 	while(1) {
 		request_handler(xaccept(fd, NULL, NULL));
diff --git a/jni/utils/misc.c b/jni/utils/misc.c
index 292c9b385..a986c0074 100644
--- a/jni/utils/misc.c
+++ b/jni/utils/misc.c
@@ -9,6 +9,8 @@
 #include <fcntl.h>
 #include <pwd.h>
 #include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/mount.h>
 
 #include "magisk.h"
 #include "utils.h"
@@ -139,14 +141,40 @@ void ps_filter_proc_name(const char *pattern, void (*func)(int)) {
 int create_links(const char *bin, const char *path) {
 	char self[PATH_MAX], linkpath[PATH_MAX];
 	if (bin == NULL) {
-		xreadlink("/proc/self/exe", self, PATH_MAX);
+		xreadlink("/proc/self/exe", self, sizeof(self));
 		bin = self;
 	}
 	int ret = 0;
 	for (int i = 0; applet[i]; ++i) {
-		snprintf(linkpath, PATH_MAX, "%s/%s", path, applet[i]);
+		snprintf(linkpath, sizeof(linkpath), "%s/%s", path, applet[i]);
 		unlink(linkpath);
 		ret |= symlink(bin, linkpath);
 	}
 	return ret;
 }
+
+#define DEV_BLOCK "/dev/block"
+
+void unlock_blocks() {	
+	char path[PATH_MAX];
+	DIR *dir;
+	struct dirent *entry;
+	int fd, OFF = 0;
+
+	if (!(dir = xopendir(DEV_BLOCK)))
+		return;
+
+	while((entry = readdir(dir))) {
+		if (entry->d_type == DT_BLK && strstr(entry->d_name, "mmc") != NULL) {
+			snprintf(path, sizeof(path), "%s/%s", DEV_BLOCK, entry->d_name);
+			if ((fd = xopen(path, O_RDONLY)) < 0)
+				continue;
+
+			if (ioctl(fd, BLKROSET, &OFF) == -1)
+				PLOGE("ioctl");
+			close(fd);
+		}
+	}
+
+	closedir(dir);
+}
diff --git a/jni/utils/utils.h b/jni/utils/utils.h
index fdf721e41..e7eb8af0b 100644
--- a/jni/utils/utils.h
+++ b/jni/utils/utils.h
@@ -61,5 +61,6 @@ ssize_t fdreadline(int fd, char *buf, size_t size);
 void ps(void (*func)(int));
 void ps_filter_proc_name(const char *filter, void (*func)(int));
 int create_links(const char *bin, const char *path);
+void unlock_blocks();
 
 #endif