1 files changed, 139 insertions, 0 deletions
diff --git a/tools/u_boot_pylib/command.py b/tools/u_boot_pylib/command.py
new file mode 100644
index 0000000000..9bbfc5bdd8
--- /dev/null
+++ b/tools/u_boot_pylib/command.py
@@ -0,0 +1,139 @@
+# SPDX-License-Identifier: GPL-2.0+
+# Copyright (c) 2011 The Chromium OS Authors.
+#
+
+import os
+
+from u_boot_pylib import cros_subprocess
+
+"""Shell command ease-ups for Python."""
+
+class CommandResult:
+    """A class which captures the result of executing a command.
+
+    Members:
+        stdout: stdout obtained from command, as a string
+        stderr: stderr obtained from command, as a string
+        return_code: Return code from command
+        exception: Exception received, or None if all ok
+    """
+    def __init__(self, stdout='', stderr='', combined='', return_code=0,
+                 exception=None):
+        self.stdout = stdout
+        self.stderr = stderr
+        self.combined = combined
+        self.return_code = return_code
+        self.exception = exception
+
+    def to_output(self, binary):
+        if not binary:
+            self.stdout = self.stdout.decode('utf-8')
+            self.stderr = self.stderr.decode('utf-8')
+            self.combined = self.combined.decode('utf-8')
+        return self
+
+
+# This permits interception of RunPipe for test purposes. If it is set to
+# a function, then that function is called with the pipe list being
+# executed. Otherwise, it is assumed to be a CommandResult object, and is
+# returned as the result for every run_pipe() call.
+# When this value is None, commands are executed as normal.
+test_result = None
+
+def run_pipe(pipe_list, infile=None, outfile=None,
+            capture=False, capture_stderr=False, oneline=False,
+            raise_on_error=True, cwd=None, binary=False,
+            output_func=None, **kwargs):
+    """
+    Perform a command pipeline, with optional input/output filenames.
+
+    Args:
+        pipe_list: List of command lines to execute. Each command line is
+            piped into the next, and is itself a list of strings. For
+            example [ ['ls', '.git'] ['wc'] ] will pipe the output of
+            'ls .git' into 'wc'.
+        infile: File to provide stdin to the pipeline
+        outfile: File to store stdout
+        capture: True to capture output
+        capture_stderr: True to capture stderr
+        oneline: True to strip newline chars from output
+        output_func: Output function to call with each output fragment
+            (if it returns True the function terminates)
+        kwargs: Additional keyword arguments to cros_subprocess.Popen()
+    Returns:
+        CommandResult object
+    """
+    if test_result:
+        if hasattr(test_result, '__call__'):
+            # pylint: disable=E1102
+            result = test_result(pipe_list=pipe_list)
+            if result:
+                return result
+        else:
+            return test_result
+        # No result: fall through to normal processing
+    result = CommandResult(b'', b'', b'')
+    last_pipe = None
+    pipeline = list(pipe_list)
+    user_pipestr =  '|'.join([' '.join(pipe) for pipe in pipe_list])
+    kwargs['stdout'] = None
+    kwargs['stderr'] = None
+    while pipeline:
+        cmd = pipeline.pop(0)
+        if last_pipe is not None:
+            kwargs['stdin'] = last_pipe.stdout
+        elif infile:
+            kwargs['stdin'] = open(infile, 'rb')
+        if pipeline or capture:
+            kwargs['stdout'] = cros_subprocess.PIPE
+        elif outfile:
+            kwargs['stdout'] = open(outfile, 'wb')
+        if capture_stderr:
+            kwargs['stderr'] = cros_subprocess.PIPE
+
+        try:
+            last_pipe = cros_subprocess.Popen(cmd, cwd=cwd, **kwargs)
+        except Exception as err:
+            result.exception = err
+            if raise_on_error:
+                raise Exception("Error running '%s': %s" % (user_pipestr, str))
+            result.return_code = 255
+            return result.to_output(binary)
+
+    if capture:
+        result.stdout, result.stderr, result.combined = (
+                last_pipe.communicate_filter(output_func))
+        if result.stdout and oneline:
+            result.output = result.stdout.rstrip(b'\r\n')
+        result.return_code = last_pipe.wait()
+    else:
+        result.return_code = os.waitpid(last_pipe.pid, 0)[1]
+    if raise_on_error and result.return_code:
+        raise Exception("Error running '%s'" % user_pipestr)
+    return result.to_output(binary)
+
+def output(*cmd, **kwargs):
+    kwargs['raise_on_error'] = kwargs.get('raise_on_error', True)
+    return run_pipe([cmd], capture=True, **kwargs).stdout
+
+def output_one_line(*cmd, **kwargs):
+    """Run a command and output it as a single-line string
+
+    The command us expected to produce a single line of output
+
+    Returns:
+        String containing output of command
+    """
+    raise_on_error = kwargs.pop('raise_on_error', True)
+    result = run_pipe([cmd], capture=True, oneline=True,
+                     raise_on_error=raise_on_error, **kwargs).stdout.strip()
+    return result
+
+def run(*cmd, **kwargs):
+    return run_pipe([cmd], **kwargs).stdout
+
+def run_list(cmd):
+    return run_pipe([cmd], capture=True).stdout
+
+def stop_all():
+    cros_subprocess.stay_alive = False