From 01cefe462fe37d1235f0518b2011d4ffb1a623d7 Mon Sep 17 00:00:00 2001
From: Pragmatic Software <pragma78@gmail.com>
Date: Tue, 15 Mar 2022 13:53:34 -0700
Subject: [PATCH] pbot-vm: fix occasional "illegal escape sequence" in
 guest-gdb

---
 applets/pbot-vm/guest/bin/guest-gdb | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/applets/pbot-vm/guest/bin/guest-gdb b/applets/pbot-vm/guest/bin/guest-gdb
index 4b03cc5f..a3ae00fc 100755
--- a/applets/pbot-vm/guest/bin/guest-gdb
+++ b/applets/pbot-vm/guest/bin/guest-gdb
@@ -142,9 +142,17 @@ sub gdb_read_result($out) {
     return $output;
 }
 
-sub gdbmi_to_json($text, $makejson = 1) {
+# convert gdb/mi text to hashtable, converting to JSON first if necessary
+sub gdbmi_to_hash($text, $makejson = 1) {
+    # convert to JSON first if necessary (gdb/mi is nearly JSON already!)
     $text =~ s/([\w-]+)=/"$1":/g if $makejson;
-    $text =~ s/\\(\d{3})/$1 >= 0x20 ? chr oct $1 : "\\$1"/ge;
+
+    # decode gdb octal escapes
+    # (sometimes \\123, othertimes \123 and I can't be arsed to investigate
+    # when and why the backslashes double up)
+    $text =~ s/\\+(\d{3})/$1 >= 0x20 ? chr oct $1 : "\\\\$1"/ge;
+
+    # return hashtable decoded from json
     return decode_json("{$text}");
 }
 
@@ -165,7 +173,7 @@ sub parse_gdbmi_output($line) {
         $text = "\"_text\":$text";
     }
 
-    my $output = gdbmi_to_json($text, $makejson);
+    my $output = gdbmi_to_hash($text, $makejson);
 
     if (exists $output->{_text}) {
         chomp $output->{_text};