fastboot: Add 'stage' command

(cherry-picked from internal nyc-iot-dev to AOSP)

New user-level command usage:

 * fastboot stage <infile>
   Sends the contents of <infile> to the device to stage for use in the
   next command.

This enables OEM commands to use data downloaded from host to device.

Bug: 35811075
Test: Manual test on imx6ul
Change-Id: I483a18f9f4205d3289ee524656b9d741b16e9fe6
(cherry-picked from commit 001c75c6c0fe6a70a1db2a65253ab3c43ec17d46)

3 files changed, 23 insertions, 0 deletions

diff --git a/fastboot/engine.cpp b/fastboot/engine.cpp
index bf887c9e9..4cf89ca85 100644
--- a/fastboot/engine.cpp
+++ b/fastboot/engine.cpp
@@ -332,6 +332,15 @@ void fb_queue_download(const char *name, void *data, uint32_t size)
     a->msg = mkmsg("downloading '%s'", name);
 }
 
+void fb_queue_download_fd(const char *name, int fd, uint32_t sz)
+{
+    Action *a;
+    a = queue_action(OP_DOWNLOAD_FD, "");
+    a->fd = fd;
+    a->size = sz;
+    a->msg = mkmsg("sending '%s' (%d KB)", name, sz / 1024);
+}
+
 void fb_queue_notice(const char *notice)
 {
     Action *a = queue_action(OP_NOTICE, "");
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index 3b524ac3c..e5ba93a59 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -371,6 +371,10 @@ static void usage() {
             "  continue                                 Continue with autoboot.\n"
             "  reboot [bootloader|emergency]            Reboot device [into bootloader or emergency mode].\n"
             "  reboot-bootloader                        Reboot device into bootloader.\n"
+            "  oem <parameter1> ... <parameterN>        Executes oem specific command.\n"
+            "  stage <infile>                           Sends contents of <infile> to stage for\n"
+            "                                           the next command. Supported only on\n"
+            "                                           Android Things devices.\n"
             "  help                                     Show this help message.\n"
             "\n"
             "options:\n"
@@ -1806,6 +1810,15 @@ int main(int argc, char **argv)
             }
             fb_set_active(slot.c_str());
             skip(2);
+        } else if(!strcmp(*argv, "stage")) {
+            require(2);
+            std::string infile(argv[1]);
+            skip(2);
+            struct fastboot_buffer buf;
+            if (!load_buf(transport, infile.c_str(), &buf) || buf.type != FB_BUFFER_FD) {
+                die("cannot load '%s'", infile.c_str());
+            }
+            fb_queue_download_fd(infile.c_str(), buf.fd, buf.sz);
         } else if(!strcmp(*argv, "oem")) {
             argc = do_oem_command(argc, argv);
         } else if(!strcmp(*argv, "flashing")) {
diff --git a/fastboot/fastboot.h b/fastboot/fastboot.h
index 3f9527055..5e9dba948 100644
--- a/fastboot/fastboot.h
+++ b/fastboot/fastboot.h
@@ -64,6 +64,7 @@ void fb_queue_query_save(const char *var, char *dest, uint32_t dest_size);
 void fb_queue_reboot(void);
 void fb_queue_command(const char *cmd, const char *msg);
 void fb_queue_download(const char *name, void *data, uint32_t size);
+void fb_queue_download_fd(const char *name, int fd, uint32_t sz);
 void fb_queue_notice(const char *notice);
 void fb_queue_wait_for_disconnect(void);
 int64_t fb_execute_queue(Transport* transport);