From b871fc687ae7670deb0e30a1c97851dadbc708c2 Mon Sep 17 00:00:00 2001
From: Johannes Truschnigg <johannes@truschnigg.info>
Date: Sat, 3 Sep 2022 14:12:00 +0200
Subject: [PATCH] Config wizard: implement TX detection/choice

---
 sqm_lagthrottle_suggest_config.sh | 35 ++++++++++++++++++++++++-------
 1 file changed, 27 insertions(+), 8 deletions(-)

diff --git a/sqm_lagthrottle_suggest_config.sh b/sqm_lagthrottle_suggest_config.sh
index 2e36ea1..c323941 100755
--- a/sqm_lagthrottle_suggest_config.sh
+++ b/sqm_lagthrottle_suggest_config.sh
@@ -55,12 +55,12 @@ echo "" >&2
 _goon
 
 
-_h "set SQM device (downstream)"
-ifb_dev=$(find /sys/devices/virtual/net/ -name ifb\* -print | head -n 1)
-if [ -e /sys/devices/virtual/net/ifb* ]
+_h "set SQM device (downstream/rx)"
+ifb_dev=$( (find /sys/devices/virtual/net/ -name ifb\* -print; echo sorry-no-dev-found) | head -n 1)
+if [ -e "${ifb_dev}" ]
 then
-  printf 'Likely network device auto-detected to apply traffic shaping to:\n\t%s\n\n' "${ifb_dev}" >&2
-  printf 'Please confirm this by supplying either this device path,\nor a custom value to replace it:\n\t' >&2
+  printf 'Auto-detected downstream (rx) network device to adjust:\n\t%s\n\n' "${ifb_dev}" >&2
+  printf 'Please confirm this by supplying either this device path again,\nor a custom value to replace it:\n\t' >&2
   read ifb_dev
 else
   printf 'FATAL: No SQM shaping network device could be determined.\nAre you sure SQM has been set up via luci-app-sqm?\n' >&2
@@ -70,12 +70,29 @@ echo "" >&2
 
 if ! [ -f "${ifb_dev}"///statistics/tx_bytes ]
 then
-  printf 'FATAL: No SQM shaping network device could be identified at\n\t%s\n' "${ifb_dev}" >&2
+  printf 'FATAL: No SQM shaping network device could be identified at\n\t"%s"\n' "${ifb_dev}" >&2
   exit 1
 fi
 
 stats_rx="${ifb_dev}"/statistics/tx_bytes
-iface_rx="${ifb_dev%%*/}"
+iface_rx="${ifb_dev##*/}"
+
+iface_tx="${iface_rx/ifb4/}"
+if [ -e /sys/class/net/"${iface_tx}" ]
+then
+  printf 'Auto-detected dependent upstream (tx) device:\n\t%s\n\n' "${iface_tx}" >&2
+  printf 'Please confirm this by supplying either this interface name again,\nor a custom value to replace it:\n\t' >&2
+else
+  printf 'Failed to auto-detect a suitable upstream/tx interface.\nPlease supply a valid sysfs device path to it.\n\t' >&2
+fi
+read iface_tx
+
+if ! [ -f /sys/class/net/"${iface_tx}"///statistics/rx_bytes ]
+then
+  printf 'FATAL: No suitable network device could be identified at\n\t"%s"\n' "/sys/class/net/${iface_tx}" >&2
+  exit 1
+fi
+stats_tx=/sys/class/net/"${iface_tx}"/statistics/rx_bytes
 _goon
 
 _h "set bandwidth limits"
@@ -89,7 +106,7 @@ echo "" >&2
 
 if ! [ ${bw_down_min}0 -lt ${bw_down_max}0 ]
 then
-  printf 'FATAL: Maximum shaping bandwith must be greater than minimum.\n'
+  printf 'FATAL: Maximum shaping bandwith must be greater than the minimum.\n'
   exit 1
 fi
 _goon
@@ -205,6 +222,8 @@ printf 'BW_MIN_RX="%d"\n' "${bw_down_min}" >> "${cfgo}"
 printf 'BW_MAX_RX="%d"\n' "${bw_down_max}" >> "${cfgo}"
 printf 'STATS_RX="%s"\n' "${stats_rx}"     >> "${cfgo}"
 printf 'IFACE_RX="%s"\n' "${iface_rx##*/}" >> "${cfgo}"
+printf 'STATS_TX="%s"\n' "${stats_tx}"     >> "${cfgo}"
+printf 'IFACE_TX="%s"\n' "${iface_tx##*/}" >> "${cfgo}"
 printf 'OPTIMIZATION_PREFERENCE="%s"\n' "${bw_or_lat_bias}" >> "${cfgo}"
 printf 'TREND_DECISION="%s"\n' "${relaxed_or_eager}" >> "${cfgo}"
 
-- 
2.39.5