Switch network module to read /proc/net/dev

This fixes issue #610 by reading bandwidth usage per-interface from
/proc/net/dev instead of globally via /proc/net/netstat. It supports the
same matching logic as elsewhere, so setting interface to '*' should
display the same sum-total bandwidth usage as the previous
implementation.
This commit is contained in:
Ciaran Downey 2021-08-25 14:47:51 -07:00
parent 4e256cf3f0
commit 9d9f959769
2 changed files with 79 additions and 90 deletions

View File

@ -43,6 +43,7 @@ class Network : public ALabel {
const std::string getNetworkState() const; const std::string getNetworkState() const;
void clearIface(); void clearIface();
bool wildcardMatch(const std::string& pattern, const std::string& text) const; bool wildcardMatch(const std::string& pattern, const std::string& text) const;
std::optional<std::pair<unsigned long long, unsigned long long>> readBandwidthUsage();
int ifid_; int ifid_;
sa_family_t family_; sa_family_t family_;

View File

@ -1,87 +1,79 @@
#include "modules/network.hpp" #include <linux/if.h>
#include <spdlog/spdlog.h> #include <spdlog/spdlog.h>
#include <sys/eventfd.h> #include <sys/eventfd.h>
#include <linux/if.h>
#include <fstream>
#include <cassert> #include <cassert>
#include <fstream>
#include <sstream>
#include <optional> #include <optional>
#include "modules/network.hpp"
#include "util/format.hpp" #include "util/format.hpp"
#ifdef WANT_RFKILL #ifdef WANT_RFKILL
#include "util/rfkill.hpp" #include "util/rfkill.hpp"
#endif #endif
namespace { namespace {
using namespace waybar::util; using namespace waybar::util;
constexpr const char *NETSTAT_FILE =
"/proc/net/netstat"; // std::ifstream does not take std::string_view as param
constexpr std::string_view BANDWIDTH_CATEGORY = "IpExt";
constexpr std::string_view BANDWIDTH_DOWN_TOTAL_KEY = "InOctets";
constexpr std::string_view BANDWIDTH_UP_TOTAL_KEY = "OutOctets";
constexpr const char *DEFAULT_FORMAT = "{ifname}"; constexpr const char *DEFAULT_FORMAT = "{ifname}";
std::ifstream netstat(NETSTAT_FILE);
std::optional<unsigned long long> read_netstat(std::string_view category, std::string_view key) {
if (!netstat) {
spdlog::warn("Failed to open netstat file {}", NETSTAT_FILE);
return {};
}
netstat.seekg(std::ios_base::beg);
// finding corresponding line (category)
// looks into the file for the first line starting by the 'category' string
auto starts_with = [](const std::string &str, std::string_view start) {
return start == std::string_view{str.data(), std::min(str.size(), start.size())};
};
std::string read;
while (std::getline(netstat, read) && !starts_with(read, category))
;
if (!starts_with(read, category)) {
spdlog::warn("Category '{}' not found in netstat file {}", category, NETSTAT_FILE);
return {};
}
// finding corresponding column (key)
// looks into the fetched line for the first word (space separated) equal to 'key'
int index = 0;
auto r_it = read.begin();
auto k_it = key.begin();
while (k_it != key.end() && r_it != read.end()) {
if (*r_it != *k_it) {
r_it = std::find(r_it, read.end(), ' ');
if (r_it != read.end()) {
++r_it;
}
k_it = key.begin();
++index;
} else {
++r_it;
++k_it;
}
}
if (r_it == read.end() && k_it != key.end()) {
spdlog::warn(
"Key '{}' not found in category '{}' of netstat file {}", key, category, NETSTAT_FILE);
return {};
}
// finally accessing value
// accesses the line right under the fetched one
std::getline(netstat, read);
assert(starts_with(read, category));
std::istringstream iss(read);
while (index--) {
std::getline(iss, read, ' ');
}
unsigned long long value;
iss >> value;
return value;
}
} // namespace } // namespace
constexpr const char *NETDEV_FILE =
"/proc/net/dev"; // std::ifstream does not take std::string_view as param
std::optional<std::pair<unsigned long long, unsigned long long>>
waybar::modules::Network::readBandwidthUsage() {
std::ifstream netdev(NETDEV_FILE);
if (!netdev) {
spdlog::warn("Failed to open netdev file {}", NETDEV_FILE);
return {};
}
// skip the headers
std::string line;
std::getline(netdev, line);
std::getline(netdev, line);
if (!netdev) {
spdlog::warn("Unexpectedly short netdev file {}", NETDEV_FILE);
return {};
}
unsigned long long receivedBytes = 0ull;
unsigned long long transmittedBytes = 0ull;
for (std::getline(netdev, line); netdev; std::getline(netdev, line)) {
std::istringstream iss(line);
std::string ifacename;
iss >> ifacename; // ifacename contains "eth0:"
ifacename.pop_back(); // remove trailing ':'
if (!checkInterface(ifacename)) {
continue;
}
// The rest of the line consists of whitespace separated counts divided
// into two groups (receive and transmit). The first column in each group
// is bytes, which is the only one we care about.
unsigned long long r = 0ull;
unsigned long long t = 0ull;
// Read received bytes
iss >> r;
// Skip all the other columns in the received group
for (int colsToSkip = 7; colsToSkip > 0; colsToSkip--) {
// skip whitespace between columns
while (iss.peek() == ' ') { iss.ignore(); }
// skip the irrelevant column
while (iss.peek() != ' ') { iss.ignore(); }
}
// Read transmit bytes
iss >> t;
spdlog::trace("read r={}, t={}, iface={}", r, t, ifacename);
receivedBytes += r;
transmittedBytes += t;
}
return {{receivedBytes, transmittedBytes}};
}
waybar::modules::Network::Network(const std::string &id, const Json::Value &config) waybar::modules::Network::Network(const std::string &id, const Json::Value &config)
: ALabel(config, "network", id, DEFAULT_FORMAT, 60), : ALabel(config, "network", id, DEFAULT_FORMAT, 60),
ifid_(-1), ifid_(-1),
@ -106,17 +98,12 @@ waybar::modules::Network::Network(const std::string &id, const Json::Value &conf
// the module start with no text, but the the event_box_ is shown. // the module start with no text, but the the event_box_ is shown.
label_.set_markup("<s></s>"); label_.set_markup("<s></s>");
auto down_octets = read_netstat(BANDWIDTH_CATEGORY, BANDWIDTH_DOWN_TOTAL_KEY); auto bandwidth = readBandwidthUsage();
auto up_octets = read_netstat(BANDWIDTH_CATEGORY, BANDWIDTH_UP_TOTAL_KEY); if (bandwidth.has_value()) {
if (down_octets) { bandwidth_down_total_ = (*bandwidth).first;
bandwidth_down_total_ = *down_octets; bandwidth_up_total_ = (*bandwidth).second;
} else { } else {
bandwidth_down_total_ = 0; bandwidth_down_total_ = 0;
}
if (up_octets) {
bandwidth_up_total_ = *up_octets;
} else {
bandwidth_up_total_ = 0; bandwidth_up_total_ = 0;
} }
@ -303,20 +290,21 @@ const std::string waybar::modules::Network::getNetworkState() const {
auto waybar::modules::Network::update() -> void { auto waybar::modules::Network::update() -> void {
std::lock_guard<std::mutex> lock(mutex_); std::lock_guard<std::mutex> lock(mutex_);
std::string tooltip_format; std::string tooltip_format;
auto down_octets = read_netstat(BANDWIDTH_CATEGORY, BANDWIDTH_DOWN_TOTAL_KEY);
auto up_octets = read_netstat(BANDWIDTH_CATEGORY, BANDWIDTH_UP_TOTAL_KEY);
unsigned long long bandwidth_down = 0; auto bandwidth = readBandwidthUsage();
if (down_octets) { auto bandwidth_down = 0ull;
bandwidth_down = *down_octets - bandwidth_down_total_; auto bandwidth_up = 0ull;
bandwidth_down_total_ = *down_octets; if (bandwidth.has_value()) {
auto down_octets = (*bandwidth).first;
auto up_octets = (*bandwidth).second;
bandwidth_down = down_octets - bandwidth_down_total_;
bandwidth_down_total_ = down_octets;
bandwidth_up = up_octets - bandwidth_up_total_;
bandwidth_up_total_ = up_octets;
} }
unsigned long long bandwidth_up = 0;
if (up_octets) {
bandwidth_up = *up_octets - bandwidth_up_total_;
bandwidth_up_total_ = *up_octets;
}
if (!alt_) { if (!alt_) {
auto state = getNetworkState(); auto state = getNetworkState();
if (!state_.empty() && label_.get_style_context()->has_class(state_)) { if (!state_.empty() && label_.get_style_context()->has_class(state_)) {