From 9bf8cedc535bd5dc37a721574d7c86b73ffd3a2e Mon Sep 17 00:00:00 2001
From: Dust1404 <2477259579@qq.com>
Date: Thu, 10 Aug 2023 22:54:19 +0800
Subject: [PATCH] watcher_unix: support symlink

---
 unix/watcher_linux.cpp |  4 ++++
 unix/watcher_macos.mm  |  5 +++++
 unix/watcher_unix.cpp  | 18 +++++++++++++++++-
 3 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/unix/watcher_linux.cpp b/unix/watcher_linux.cpp
index cd113c8..c449229 100644
--- a/unix/watcher_linux.cpp
+++ b/unix/watcher_linux.cpp
@@ -12,6 +12,7 @@
 #include <cstdlib>
 #include <cstring>
 #include <linux/elf.h>
+#include <linux/limits.h>
 #include <string>
 #include <sys/fcntl.h>
 #include <sys/resource.h>
@@ -96,3 +97,6 @@ ssize_t calculateStaticMemoryUsage(const std::string &fileName) {
 ssize_t getMemoryRLimit(ssize_t memoryLimitInMB) { return memoryLimitInMB * 1024 * 1024; }
 
 size_t getMaxRSSInByte(long ru_maxrss) { return ru_maxrss * 1024; }
+
+char fileNameBuf[PATH_MAX];
+size_t maxPathLength = PATH_MAX;
diff --git a/unix/watcher_macos.mm b/unix/watcher_macos.mm
index 5e44709..e969f21 100644
--- a/unix/watcher_macos.mm
+++ b/unix/watcher_macos.mm
@@ -13,6 +13,7 @@
 #include <cstdlib>
 #include <cstring>
 #include <errno.h>
+#include <limits.h>
 #include <mach-o/fat.h>
 #include <mach-o/loader.h>
 #include <mach-o/utils.h>
@@ -20,6 +21,7 @@
 #include <sys/fcntl.h>
 #include <sys/resource.h>
 #include <sys/sysctl.h>
+#include <sys/syslimits.h>
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/wait.h>
@@ -147,3 +149,6 @@ ssize_t calculateStaticMemoryUsage(const std::string &fileName) {
 ssize_t getMemoryRLimit(ssize_t memoryLimitInMB) { return memoryLimitInMB * 1024 * (isAppleSilicon ? 4 : 1); }
 
 size_t getMaxRSSInByte(long ru_maxrss) { return ru_maxrss / (isAppleSilicon ? 4 : 1); }
+
+char fileNameBuf[MAX_INPUT];
+size_t maxPathLength = MAX_INPUT;
diff --git a/unix/watcher_unix.cpp b/unix/watcher_unix.cpp
index bffa505..890ce4e 100644
--- a/unix/watcher_unix.cpp
+++ b/unix/watcher_unix.cpp
@@ -30,6 +30,8 @@ extern void initWatcher();
 extern ssize_t calculateStaticMemoryUsage(const std::string &);
 extern ssize_t getMemoryRLimit(ssize_t memoryLimitInMB);
 extern size_t getMaxRSSInByte(long ru_maxrss);
+extern char fileNameBuf[];
+extern size_t maxPathLength;
 
 /**
  * argv[1]: QString("\"%1\" %2").arg(executableFile, arguments) in `judgingthread.cpp` 执行命令
@@ -53,7 +55,21 @@ auto main(int /*argc*/, char *argv[]) -> int {
 	std::string fileName(argv[1]);
 	fileName = fileName.substr(1);
 	fileName = fileName.substr(0, fileName.find("\""));
-	// TODO: 处理符号链接
+
+	int rc = readlink(fileName.c_str(), fileNameBuf, maxPathLength);
+	if (rc > 0) {
+		fileNameBuf[rc] = '\0';
+		if (fileNameBuf[0] == '/') { // absolute path
+			fileName = fileNameBuf;
+		} else { // relative path
+			size_t dir_end = fileName.find_last_of('/');
+			if (dir_end == std::string::npos) {
+				fileName = std::string("./") + fileNameBuf;
+			} else {
+				fileName = fileName.substr(0, dir_end + 1) + fileNameBuf;
+			}
+		}
+	}
 
 	if (memoryLimit > 0) {
 		ssize_t staticMemoryUsage = calculateStaticMemoryUsage(fileName);