recovery: Add "boot-fastboot" command to BCB.

This change adds a new "boot-fastboot" command in order to boot into fastboot
without overwriting recovery tasks. This also allows bootloaders to boot
directly into userspace fastboot from the bootloader menu, or via
bootloader fastboot.

Bug: 112277594
Test: adb reboot fastboot
Change-Id: Ia0c9a0961a76c6cbe19486590179abaa50d93f58

1 files changed, 12 insertions, 1 deletions

diff --git a/recovery_main.cpp b/recovery_main.cpp
index 99f96509..020a5314 100644
--- a/recovery_main.cpp
+++ b/recovery_main.cpp
@@ -97,8 +97,13 @@ static std::vector<std::string> get_args(const int argc, char** const argv) {
   }
   stage = std::string(boot.stage);
 
+  std::string boot_command;
   if (boot.command[0] != 0) {
-    std::string boot_command = std::string(boot.command, sizeof(boot.command));
+    if (memchr(boot.command, '\0', sizeof(boot.command))) {
+      boot_command = std::string(boot.command);
+    } else {
+      boot_command = std::string(boot.command, sizeof(boot.command));
+    }
     LOG(INFO) << "Boot command: " << boot_command;
   }
 
@@ -149,6 +154,12 @@ static std::vector<std::string> get_args(const int argc, char** const argv) {
     LOG(ERROR) << "Failed to set BCB message: " << err;
   }
 
+  // Finally, if no arguments were specified, check whether we should boot
+  // into fastboot.
+  if (args.size() == 1 && boot_command == "boot-fastboot") {
+    args.emplace_back("--fastboot");
+  }
+
   return args;
 }