Parse arguments

Author: steven112163

Diff for: .gitignore

@@ -1,3 +1 @@
-objs
-hw1
 .vscode

Diff for: HW1/.gitignore

@@ -0,0 +1,2 @@
+objs
+hw1

Diff for: HW2/.gitignore

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+logger_objs
+so_objs
+logger
+logger.so
+.vscode

Diff for: HW2/Makefile

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+CXX = g++
+
+LOGGER_DIR = logger_objs/
+LOGGER_FLAGS = -O3 -std=c++17 -Wall -I.
+LOGGER_FILES = hw2.cpp
+LOGGER_OBJS = $(addprefix $(LOGGER_DIR), $(LOGGER_FILES:.cpp=.o))
+LOGGER = logger
+
+SO_DIR = so_objs/
+SO_FLAGS = -O3 -std=c++17 -shared -fPIC -ldl -Wall -I.
+SO_FILES = shared_object.cpp
+SO_OBJS = $(addprefix $(SO_DIR), $(SO_FILES:.cpp=.o))
+SHARED_OBJECT = logger.so
+
+.PHONY: all create compile_logger compile_so clean
+
+all: create compile_logger compile_so
+
+create:
+	mkdir -p $(LOGGER_DIR)
+	mkdir -p $(SO_DIR)
+
+compile_logger: $(LOGGER_OBJS)
+	$(CXX) $^ -o $(LOGGER) $(LOGGER_FLAGS)
+
+$(LOGGER_DIR)%.o: %.cpp
+	$(CXX) -c $< -o $@ $(LOGGER_FLAGS)
+
+compile_so: $(SO_OBJS)
+	$(CXX) $^ -o $(SHARED_OBJECT) $(SO_FLAGS)
+
+$(SO_DIR)%.o: %.cpp
+	$(CXX) -c $< -o $@ $(SO_FLAGS)
+
+clean:
+	rm -rf $(LOGGER) $(SHARED_OBJECT) $(LOGGER_DIR) $(SO_DIR)

Diff for: HW2/hw2.cpp

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+#include "hw2.hpp"
+
+int main(int argc, char* argv[]) {
+    // Parse arguments
+    char ch{};
+    std::string output_file{};
+    std::string logger_path{"./logger.so"};
+    while ((ch = getopt(argc, argv, "o:p:")) != -1) {
+        switch (ch) {
+            case 'o': {
+                output_file = std::string(optarg);
+                break;
+            }
+            case 'p': {
+                logger_path = std::string(optarg);
+                break;
+            }
+            default: {
+                std::cout << "usage: ./logger [-o file] [-p sopath] [--] cmd "
+                             "[cmd args ...]\n"
+                          << "        -p: set the path to logger.so, default = "
+                             "./logger.so\n"
+                          << "        -o: print output to file, print to "
+                             "\"stderr\" if no file specified\n"
+                          << "        --: separate the arguments for logger "
+                             "and for the command\n"
+                          << std::endl;
+                return 1;
+            }
+        }
+    }
+
+    if (optind == argc) {
+        std::cout << "no command given\n" << std::endl;
+        return 1;
+    }
+
+    // Parse command with its arguments
+    std::string command{argv[optind]};
+    std::vector<std::string> arguments{};
+    for (int idx{optind + 1}; idx < argc; idx++)
+        arguments.emplace_back(argv[idx]);
+
+    return 0;
+}

Diff for: HW2/hw2.hpp

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+#include <unistd.h>
+
+#include <iostream>
+#include <string>
+#include <vector>

Diff for: HW2/shared_object.cpp

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+#include <shared_object.hpp>

Diff for: HW2/shared_object.hpp

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+#include <dlfcn.h>