adb: put legacy shell: service back in.

ddmlib does not use the ADB client, but instead connects directly to
the adb server. This breaks some of the assumptions I previously made
when enabling the shell protocol.

To fix this, the adb server now defaults to no protocol for the
standalone command, and the shell protocol must be explicitly requested
by the client. For example:
  shell:echo foo     -- no shell protocol
  shell,v2:echo foo  -- shell protocol

As long as I was touching the shell service arguments I also changed
them to no longer duplicate the command-line arguments. This allows
more flexibility to change the adb client CLI if necessary and makes
the code more readable.

Bug: http://b/24148636
Change-Id: I28d5ae578cf18cbe79347dc89cea1750ff4571a8

1 files changed, 22 insertions, 17 deletions

diff --git a/services.cpp b/services.cpp
index 1153c31..e832b1e 100644
--- a/services.cpp
+++ b/services.cpp
@@ -46,6 +46,7 @@
 #include "adb_utils.h"
 #include "file_sync_service.h"
 #include "remount_service.h"
+#include "services.h"
 #include "shell_service.h"
 #include "transport.h"
 
@@ -195,34 +196,38 @@ void reverse_service(int fd, void* arg)
 }
 
 // Shell service string can look like:
-//   shell[args]:[command]
-// Currently the only supported args are -T (force raw) and -t (force PTY).
+//   shell[,arg1,arg2,...]:[command]
 static int ShellService(const std::string& args, const atransport* transport) {
     size_t delimiter_index = args.find(':');
     if (delimiter_index == std::string::npos) {
         LOG(ERROR) << "No ':' found in shell service arguments: " << args;
         return -1;
     }
+
     const std::string service_args = args.substr(0, delimiter_index);
     const std::string command = args.substr(delimiter_index + 1);
 
-    SubprocessType type;
-    if (service_args.empty()) {
-        // Default: use PTY for interactive, raw for non-interactive.
-        type = (command.empty() ? SubprocessType::kPty : SubprocessType::kRaw);
-    } else if (service_args == "-T") {
-        type = SubprocessType::kRaw;
-    } else if (service_args == "-t") {
-        type = SubprocessType::kPty;
-    } else {
-        LOG(ERROR) << "Unsupported shell service arguments: " << args;
-        return -1;
+    // Defaults:
+    //   PTY for interactive, raw for non-interactive.
+    //   No protocol.
+    SubprocessType type(command.empty() ? SubprocessType::kPty
+                                        : SubprocessType::kRaw);
+    SubprocessProtocol protocol = SubprocessProtocol::kNone;
+
+    for (const std::string& arg : android::base::Split(service_args, ",")) {
+        if (arg == kShellServiceArgRaw) {
+            type = SubprocessType::kRaw;
+        } else if (arg == kShellServiceArgPty) {
+            type = SubprocessType::kPty;
+        } else if (arg == kShellServiceArgShellProtocol) {
+            protocol = SubprocessProtocol::kShell;
+        }
+        else if (!arg.empty()) {
+            LOG(ERROR) << "Unsupported shell service arguments: " << args;
+            return -1;
+        }
     }
 
-    SubprocessProtocol protocol =
-            (transport->CanUseFeature(kFeatureShell2) ? SubprocessProtocol::kShell
-                                                      : SubprocessProtocol::kNone);
-
     return StartSubprocess(command.c_str(), type, protocol);
 }