From 7966a722064e04f3986fd72f4ead66e7cd07b0ec Mon Sep 17 00:00:00 2001
From: Sangwan Kwon <sangwan.kwon@samsung.com>
Date: Tue, 25 Feb 2020 15:53:41 +0900
Subject: [PATCH] Fix to get process identifier from cmdline

Signed-off-by: Sangwan Kwon <sangwan.kwon@samsung.com>
---
 src/vist/common/tests/process.cpp |  6 ++---
 src/vist/policy/api.cpp           |  4 +--
 src/vist/process.hpp              | 51 +++++++++++++++++++--------------------
 src/vist/service/tests/core.cpp   |  4 +--
 4 files changed, 32 insertions(+), 33 deletions(-)

diff --git a/src/vist/common/tests/process.cpp b/src/vist/common/tests/process.cpp
index fea8f1f..a7b79d4 100644
--- a/src/vist/common/tests/process.cpp
+++ b/src/vist/common/tests/process.cpp
@@ -24,15 +24,15 @@ using namespace vist;
 
 TEST(ProcessTests, path_positive)
 {
-	auto name = Process::GetPath(Process::GetPid());
-	EXPECT_EQ("/usr/bin/vist-test", name);
+	auto name = Process::GetIdentifier(Process::GetPid());
+	EXPECT_EQ("vist-test", name);
 }
 
 TEST(ProcessTests, path_negative)
 {
 	bool raised = false;
 	try {
-		Process::GetPath(-1);
+		Process::GetIdentifier(-1);
 	} catch(...) {
 		raised = true;
 	}
diff --git a/src/vist/policy/api.cpp b/src/vist/policy/api.cpp
index 61ff676..98e6b6b 100644
--- a/src/vist/policy/api.cpp
+++ b/src/vist/policy/api.cpp
@@ -39,9 +39,9 @@ void API::Admin::Set(const std::string& policy, const PolicyValue& value)
 	std::string admin;
 	auto peer = rmi::Gateway::GetPeerCredentials();
 	if (peer == nullptr)
-		admin = Process::GetPath(Process::GetPid());
+		admin = Process::GetIdentifier(Process::GetPid());
 	else
-		admin = Process::GetPath(peer->pid);
+		admin = Process::GetIdentifier(peer->pid);
 
 	PolicyManager::Instance().set(policy, value, admin);
 }
diff --git a/src/vist/process.hpp b/src/vist/process.hpp
index 29e4ebc..ff7548d 100644
--- a/src/vist/process.hpp
+++ b/src/vist/process.hpp
@@ -39,34 +39,24 @@ struct Process {
 		return ::getpid();
 	}
 
-	/// TODO(Sangwan): Unify the method which get process identifier
-	static std::string GetPath(pid_t pid)
+	static std::string GetIdentifier(pid_t pid)
 	{
-		std::string exe = "/proc/" + std::to_string(pid) + "/exe";
-
-		/// c++17 std::filesystem::read_symlink
-		std::vector<char> buf(1024);
 		errno = 0;
-		auto size = ::readlink(exe.c_str(), buf.data(), buf.size());
-		if (size == -1) {
-			WARN(VIST) << "Failed to get process path by exe: " << exe
-					   << ", errno: " << errno;
-
-			std::string cmdline = "/proc/" + std::to_string(pid) + "/cmdline";
-			int fd = ::open(cmdline.c_str(), O_RDONLY);
-			if (fd == -1)
-				THROW(ErrCode::RuntimeError) << "Failed to get process path: " << cmdline;
+		std::string cmdline = "/proc/" + std::to_string(pid) + "/cmdline";
+		int fd = ::open(cmdline.c_str(), O_RDONLY);
+		if (fd == -1)
+			THROW(ErrCode::RuntimeError) << "Failed to get process path: " << cmdline;
 
-			errno = 0;
-			size = ::read(fd, buf.data(), buf.size());
-			::close(fd);
+		errno = 0;
+		std::vector<char> buf(1024);
+		auto size = ::read(fd, buf.data(), buf.size());
+		::close(fd);
 
-			if (size == -1)
-				THROW(ErrCode::RuntimeError) << "Failed to get process path: " << cmdline
-											 << ", errno: " << errno;
+		if (size == -1)
+			THROW(ErrCode::RuntimeError) << "Failed to get process path: " << cmdline
+										 << ", errno: " << errno;
 
-			buf[size - 1] = '\0';
-		}
+		buf[size - 1] = '\0';
 
 		return canonicalize(std::string(buf.begin(), buf.begin() + size));
 	}
@@ -74,9 +64,18 @@ struct Process {
 private:
 	static std::string canonicalize(std::string&& s)
 	{
-		auto predicate = [](unsigned char c){ return std::isspace(c) || c == '\0'; };
-		auto base = std::find_if(s.begin(), s.end(), predicate);
-		s.erase(base, s.end());
+		{ /// rtrim
+			auto predicate = [](unsigned char c){ return std::isspace(c) || c == '\0'; };
+			auto base = std::find_if(s.begin(), s.end(), predicate);
+			s.erase(base, s.end());
+		}
+
+		{ /// ltrim
+			auto predicate = [](unsigned char c){ return c == '/'; };
+			auto base = std::find_if(s.rbegin(), s.rend(), predicate).base();
+			s.erase(s.begin(), base);
+		}
+
 		return s;
 	}
 };
diff --git a/src/vist/service/tests/core.cpp b/src/vist/service/tests/core.cpp
index c7fc564..83d6f73 100644
--- a/src/vist/service/tests/core.cpp
+++ b/src/vist/service/tests/core.cpp
@@ -41,7 +41,7 @@ TEST_F(CoreTests, query_select)
 
 TEST_F(CoreTests, query_update)
 {
-	policy::API::Admin::Enroll("/usr/bin/vist-test");
+	policy::API::Admin::Enroll("vist-test");
 
 	std::string statement = "SELECT * FROM policy WHERE name = 'sample-int-policy'";
 	auto rows = Vistd::Query(statement);
@@ -56,5 +56,5 @@ TEST_F(CoreTests, query_update)
 	rows = Vistd::Query(statement);
 	EXPECT_EQ(rows[0]["value"], "I/10");
 
-	policy::API::Admin::Disenroll("/usr/bin/vist-test");
+	policy::API::Admin::Disenroll("vist-test");
 }
-- 
2.7.4