#!/usr/bin/env python

# Decode a stack trace from getcallerpcs() to kernel symbols.
# Peter H. Froehlich <phf@acm.org>, 600.318/418, Spring 2011
#
# $ ./depcs 1072fa 1073c4 106d4a 103024 102fdd 0 0 0 0 0
# 1078010 ['mappages']
# 1078212 ['setupkvm']
# 1076554 ['kvmalloc']
# 1060900 ['mainc']
# 1060829 ['jmpkstack']

import sys

# read the symbols, mapping each address to all known names

raw = {}
with open("kernel.sym") as f:
    for s in f:
        adr, sym = s.strip().split()
        adr = int(adr, 16)
        if adr in raw:
            raw[adr].append(sym)
        else:
            raw[adr] = [sym]

# for a given address, we need to determine what range it
# lies in; there are fancy data structures or this, which
# we ignore; let's just sort the keys instead

sort = sorted(raw.keys())

# now we can find the least key greater than an address;
# if there's none, we use the last address we know; doh!

def least(x):
    for i in range(len(sort)-1):
        if sort[i] <= x < sort[i+1]:
            return sort[i]
    return sort[-1]

# therefore we can decode a backtrace (ignoring address
# 0 since it's useless for xv6)

for adr in sys.argv[1:]:
    adr = int(adr, 16)
    if adr != 0:
        print adr, raw[least(adr)]