Sample Python script for Mdbg-Python extension

Article
08/31/2005

#----------------------------------------------------
# Python Script for MDbg commands
#----------------------------------------------------

#----------------------------------------------------
# Support for accessing the root Shell object.
# We can get at everything else from this.
#----------------------------------------------------
#Shell = None

# Helper to give this module access to the "Shell" Object
# Since globals are public, you can set this directly too.
def SetShell(x):
    #global g_Shell
    #Shell = x
    pass

def GetShell():
# global Shell
return Shell

def GetDebugger():
return GetShell().Debugger;

# Explicitly print to Mdbg shells' Output.
# @todo - Python "Print" command should do this too.
# currently, Print goes to sys.stdout.
def ShPrint(x):
GetShell().IO.WriteOutput("STDOUT", x)

# Execute an Mdbg command.
def ShExe(cmd):
MDbgUtil.ExecuteCommand(cmd)

def fib(n):
    print 'n =', n
    if n > 1:
        return n * fib(n - 1)
    else:
        print 'end of the line'
        return 1

# Helper alias to get the current MDbgProcess object
# Throws if none available.
def CurProc():
return GetDebugger().Processes.Active

# Helper alias to get the current MDbgThread object
# Throws if none available.
def CurThread(): return CurProc().Threads.Active

# Helper to get the current frame.
# Throws if none available.
def CurFrame(): return CurThread().CurrentFrame
def CurFrame2(): return CurThread().CurrentFrame.CorFrame

#----------------------------------------------------
# Helper to print the callstack.
# Uses MDbgFrame.ToString()
#----------------------------------------------------
def PrintStack():
    i = 0
    for x in CurThread().Frames:
        print "%d) %s" % (i, x)
        i = i + 1
    print '------------'

#----------------------------------------------------
# Get locals for the current frame.
# Returns an array of MdbgValue[]
#----------------------------------------------------
def CurLocals():
return CurFrame().Function.GetActiveLocalVars(CurFrame())

#----------------------------------------------------
# Get the current arguments (aka parameters) to the current frame
#----------------------------------------------------
def CurArgs():
return CurFrame().Function.GetArguments(CurFrame())

#----------------------------------------------------
# pretty print a value. May be multiline result
# Don't use fun-eval.
# V can be either a single MDgValue or an MDbgValue[]
#----------------------------------------------------
def PrintVal(v):
    # Check for MDbgValue[]
    if str(type(v))=="<type 'Microsoft.Samples.Debugging.MdbgEngine.MDbgValue[]'>":
        for x in v:
            PrintVal(x)
    else:
        PrintValHelper(v, "")

# Helper to print with indent.
def PrintValHelper(v, indent):
    if (v.IsComplexType):
        print indent + v.Name + "=Complex Type: (" + v.TypeName + ")"
        for x in v.GetFields():
            PrintValHelper(x, indent+" ")
    elif (v.IsArrayType):
        print indent + v.Name + "=array Type: (" + v.TypeName + ")"
        for x in v.GetArrayItems():
            PrintValHelper(x, indent+" ")
    else:
        print indent + v.Name + "=" + v.GetStringValue(0, False) + "(" + v.TypeName + ")";

#----------------------------------------------------
# Get an Mdbg value for the given name.
# This is short because it will likely be a common operator.
# Can be a local or parameter
# This provides __repr__ on the output value so that we
# have a pretty string-izing operator.
# returns none if not found (@todo - perhaps throw?)
#----------------------------------------------------
def E(name):
    v = _CheckValArray(name, CurLocals())
    if v == None:
        v = _CheckValArray(name, CurArgs())

# if v != None v.__repr__ = _ValToString
return v

# Get a value as a simple pretty string:
def _ValToString(v):
return v.GetStringValue(0, False)

def E2(name):
return _ValToString(E(name))

# Helper to see if any items in v array have the given name.
# V is an MDbgValue[]
def _CheckValArray(name, v):
    for x in v:
        if x.Name == name:
            return x
    return None

# Test for hit counter breakpoints.
# @todo - they all share global right now - uses Classes to give each their own data?
g_Total = 0;
def q1(hits):
    global g_Total
    g_Total = g_Total + 1
    print "Inside hit counter bp:%d (of %d hits)" % (g_Total, hits)
    if g_Total < hits:
        return None
    else:
        g_Total = 0
        return "Stop at %d" % (hits)

# Test class
class MyC:
    def __init__(self): self.val=0
    def Inc(self): self.val = self.val + 1
    def Dev(self): self.val = self.val - 1

Sample Python script for Mdbg-Python extension

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