From 1d29828d1b63fb350c24440ad7bd037f33cf1364 Mon Sep 17 00:00:00 2001
From: springzfx <springzfx@gmail.com>
Date: Tue, 26 May 2020 23:04:12 +0800
Subject: [PATCH] remove path max len limit

---
 src/cgproxy.hpp       |  4 ++--
 src/cgroup_attach.cpp | 30 ++++++++++++++++++++----------
 src/common.cpp        | 11 ++++-------
 src/common.h          |  3 ++-
 4 files changed, 28 insertions(+), 20 deletions(-)

diff --git a/src/cgproxy.hpp b/src/cgproxy.hpp
index d44769c..6d5d699 100644
--- a/src/cgproxy.hpp
+++ b/src/cgproxy.hpp
@@ -5,8 +5,8 @@
 #include <nlohmann/json.hpp>
 #include <unistd.h>
 using json = nlohmann::json;
-using namespace CGPROXY;
-using namespace CGPROXY::CONFIG;
+using namespace ::CGPROXY;
+using namespace ::CGPROXY::CONFIG;
 
 namespace CGPROXY::CGPROXY {
 
diff --git a/src/cgroup_attach.cpp b/src/cgroup_attach.cpp
index 1f64169..2667727 100644
--- a/src/cgroup_attach.cpp
+++ b/src/cgroup_attach.cpp
@@ -19,8 +19,8 @@ string get_cgroup2_mount_point() {
   stringstream buffer;
   FILE *fp = popen("findmnt -t cgroup2 -n -o TARGET", "r");
   if (!fp) return "";
-  char buf[64];
-  while (fgets(buf, 64, fp) != NULL) { buffer << buf; }
+  char buf[READ_SIZE_MAX];
+  while (fgets(buf, READ_SIZE_MAX, fp) != NULL) { buffer << buf; }
   pclose(fp);
   string s = buffer.str();
   s.pop_back(); // remove newline character
@@ -32,17 +32,27 @@ string getCgroup(const pid_t &pid) { return getCgroup(to_str(pid)); }
 string getCgroup(const string &pid) {
   string cgroup_f = to_str("/proc/", pid, "/cgroup");
   if (!fileExist(cgroup_f)) return "";
-  char buf[128];
+
+  stringstream buffer;
+  string cgroup;
   FILE *f = fopen(cgroup_f.c_str(), "r");
-  int id;
-  char cgroup[256];
-  while (fgets(buf, 128, f) != NULL) {
-    if (buf[0] == '0') {
-      if (sscanf(buf, "%*i::%s", cgroup) == 1) return cgroup;
-      error("sscanf %s failed", buf);
+  char buf[READ_SIZE_MAX] = "";
+  char *flag = buf;
+  while (flag != NULL) {
+    buffer.clear();
+    while (!flag || buf[strlen(buf) - 1] != '\n') {
+      flag = fgets(buf, READ_SIZE_MAX, f);
+      if (flag) buffer << buf;
+    }
+    string line = buffer.str();
+    if (line[0] == '0') { // 0::/user.slice/user-1000.slice
+      cgroup = (*(line.end() - 1) == '\n') ? line.substr(3, line.length() - 4)
+                                           : line.substr(3);
+      break;
     }
   }
-  return "";
+  fclose(f);
+  return cgroup;
 }
 
 bool validate(string pid, string cgroup) {
diff --git a/src/common.cpp b/src/common.cpp
index efcc6f6..2879597 100644
--- a/src/common.cpp
+++ b/src/common.cpp
@@ -1,7 +1,5 @@
 #include "common.h"
 #include <fstream>
-#include <limits.h>
-#include <linux/limits.h>
 #include <regex>
 #include <sys/stat.h>
 #include <unistd.h>
@@ -54,7 +52,6 @@ vector<int> bash_pidof(const string &path) {
   FILE *fp = popen(to_str("pidof ", path).c_str(), "r");
   if (!fp) return pids;
   int pid;
-  char buf[64];
   while (fscanf(fp, "%d", &pid) != EOF) { pids.push_back(pid); }
   pclose(fp);
   return pids;
@@ -64,8 +61,8 @@ string bash_which(const string &name) {
   stringstream buffer;
   FILE *fp = popen(to_str("which ", name).c_str(), "r");
   if (!fp) return "";
-  char buf[64];
-  while (fgets(buf, 64, fp) != NULL) { buffer << buf; }
+  char buf[READ_SIZE_MAX];
+  while (fgets(buf, READ_SIZE_MAX, fp) != NULL) { buffer << buf; }
   pclose(fp);
   string s = buffer.str();
   s.pop_back(); // remove newline character
@@ -76,8 +73,8 @@ string bash_readlink(const string &path) {
   stringstream buffer;
   FILE *fp = popen(to_str("readlink -e ", path).c_str(), "r");
   if (!fp) return "";
-  char buf[64];
-  while (fgets(buf, 64, fp) != NULL) { buffer << buf; }
+  char buf[READ_SIZE_MAX];
+  while (fgets(buf, READ_SIZE_MAX, fp) != NULL) { buffer << buf; }
   pclose(fp);
   string s = buffer.str();
   s.pop_back(); // remove newline character
diff --git a/src/common.h b/src/common.h
index 24c97db..9d297db 100644
--- a/src/common.h
+++ b/src/common.h
@@ -15,6 +15,7 @@ using namespace std;
 #define SOCKET_PATH "/tmp/cgproxy_unix_socket"
 #define LISTEN_BACKLOG 64
 #define DEFAULT_CONFIG_FILE "/etc/cgproxy/config.json"
+#define READ_SIZE_MAX 128
 
 #define CGROUP_PROXY_PRESVERED "/proxy.slice"
 #define CGROUP_NOPROXY_PRESVERED "/noproxy.slice"
@@ -87,4 +88,4 @@ string bash_which(const string &name);
 string bash_readlink(const string &path);
 string getRealExistPath(const string &name);
 
-#endif
\ No newline at end of file
+#endif