From 1bbc39d9bd6a7e25e00972074fbe03003e219c26 Mon Sep 17 00:00:00 2001
From: disconnect3d <dominik.b.czarnota@gmail.com>
Date: Sat, 5 Sep 2020 03:41:41 -0700
Subject: [PATCH] format_args: display fd path
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E.g. for calls like this:
```
 ► 0x555555554a57 <main+296>    call   ioctl@plt <ioctl@plt>
        fd: 0x3
        request: 0xae01
        vararg: 0x0
```

We want to display the `fd` as: `fd: 0x3 (/some/path)` fetched from
`readlink -f /proc/$PID/fd/$FD`.
---
 pwndbg/arguments.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/pwndbg/arguments.py b/pwndbg/arguments.py
index e92357279..e067fd3d3 100644
--- a/pwndbg/arguments.py
+++ b/pwndbg/arguments.py
@@ -201,5 +201,11 @@ def format_args(instruction):
     for arg, value in get(instruction):
         code   = arg.type != 'char'
         pretty = pwndbg.chain.format(value, code=code)
+
+        # Enhance args display
+        if arg.name == 'fd' and isinstance(value, int):
+            path = pwndbg.file.readlink('/proc/%d/fd/%d' % (pwndbg.proc.pid, value))
+            pretty += ' (%s)' % path
+
         result.append('%-10s %s' % (N.argument(arg.name) + ':', pretty))
     return result