[ndk-gdb.py] Select which ps command to run on the device.

Saves an adb roundtrip.

Bug: http://b/23793246
Change-Id: Iffce325f7576102cdbf8d2ca7530c77c049b1503

1 files changed, 16 insertions, 7 deletions

diff --git a/ndk-gdb.py b/ndk-gdb.py
index e206dcdc1..7010a5d34 100755
--- a/ndk-gdb.py
+++ b/ndk-gdb.py
@@ -451,13 +451,22 @@ def get_pid_of(package_name):
     package names like com.exampleisverylongtoolongbyfar.plasma
     exceed the limit.
     '''
-    ps_command = 'ps'
-    retcode,output = adb_cmd(False, ['shell', 'readlink $(which ps)'])
-    if output:
-        output = output.replace('\r', '').splitlines()[0]
-    if output == 'busybox':
-        ps_command = 'ps -w'
-    retcode,output = adb_cmd(False,['shell', ps_command])
+
+    # Perform the check on the device to avoid an adb roundtrip
+    # Some devices might not have readlink or which, so we need to check for
+    # them.
+    ps_script = '''
+        if [ ! -x /system/bin/readlink -o ! -x /system/bin/which ]; then
+            ps;
+        elif [ $(readlink $(which ps)) == "toolbox" ]; then
+            ps;
+        else
+            ps -w;
+        fi
+    '''
+    ps_script = " ".join([line.strip() for line in ps_script.splitlines()])
+
+    retcode, output = adb_cmd(False, ['shell', ps_script])
     output = output.replace('\r', '').splitlines()
     columns = output.pop(0).split()
     try: