support "sideload over ADB" mode
Rather than depending on the existence of some place to store a file
that is accessible to users on an an unbootable device (eg, a physical
sdcard, external USB drive, etc.), add support for sideloading
packages sent to the device with adb.
This change adds a "minimal adbd" which supports nothing but receiving
a package over adb (with the "adb sideload" command) and storing it to
a fixed filename in the /tmp ramdisk, from where it can be verified
and sideloaded in the usual way. This should be leave available even
on locked user-build devices.
The user can select "apply package from ADB" from the recovery menu,
which starts minimal-adb mode (shutting down any real adbd that may be
running). Once minimal-adb has received a package it exits
(restarting real adbd if appropriate) and then verification and
installation of the received package proceeds.
Change-Id: I6fe13161ca064a98d06fa32104e1f432826582f5
diff --git a/minadbd/utils.c b/minadbd/utils.c
new file mode 100644
index 0000000..91518ba
--- /dev/null
+++ b/minadbd/utils.c
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * 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.
+ */
+#include "utils.h"
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+
+char*
+buff_addc (char* buff, char* buffEnd, int c)
+{
+ int avail = buffEnd - buff;
+
+ if (avail <= 0) /* already in overflow mode */
+ return buff;
+
+ if (avail == 1) { /* overflowing, the last byte is reserved for zero */
+ buff[0] = 0;
+ return buff + 1;
+ }
+
+ buff[0] = (char) c; /* add char and terminating zero */
+ buff[1] = 0;
+ return buff + 1;
+}
+
+char*
+buff_adds (char* buff, char* buffEnd, const char* s)
+{
+ int slen = strlen(s);
+
+ return buff_addb(buff, buffEnd, s, slen);
+}
+
+char*
+buff_addb (char* buff, char* buffEnd, const void* data, int len)
+{
+ int avail = (buffEnd - buff);
+
+ if (avail <= 0 || len <= 0) /* already overflowing */
+ return buff;
+
+ if (len > avail)
+ len = avail;
+
+ memcpy(buff, data, len);
+
+ buff += len;
+
+ /* ensure there is a terminating zero */
+ if (buff >= buffEnd) { /* overflow */
+ buff[-1] = 0;
+ } else
+ buff[0] = 0;
+
+ return buff;
+}
+
+char*
+buff_add (char* buff, char* buffEnd, const char* format, ... )
+{
+ int avail;
+
+ avail = (buffEnd - buff);
+
+ if (avail > 0) {
+ va_list args;
+ int nn;
+
+ va_start(args, format);
+ nn = vsnprintf( buff, avail, format, args);
+ va_end(args);
+
+ if (nn < 0) {
+ /* some C libraries return -1 in case of overflow,
+ * but they will also do that if the format spec is
+ * invalid. We assume ADB is not buggy enough to
+ * trigger that last case. */
+ nn = avail;
+ }
+ else if (nn > avail) {
+ nn = avail;
+ }
+
+ buff += nn;
+
+ /* ensure that there is a terminating zero */
+ if (buff >= buffEnd)
+ buff[-1] = 0;
+ else
+ buff[0] = 0;
+ }
+ return buff;
+}