implement commit-tree command

.gitignore

@@ -387,4 +387,4 @@ Makefile
 
 .idea/
 
-cmake*/
+cmake-build*/

CMakeLists.txt

@@ -8,6 +8,14 @@ FetchContent_Declare(ZStrGitRepo
 )
 FetchContent_MakeAvailable(ZStrGitRepo) # defines INTERFACE target 'zstr::zstr'
 
+set(BUILD_TZ_LIB ON)# timezone support
+
+FetchContent_Declare( date_src
+        GIT_REPOSITORY https://gitlab.com/JosephA1997/date.git
+        GIT_TAG        "master"
+)
+FetchContent_MakeAvailable(date_src)
+
 set(CMAKE_CXX_STANDARD 23)
 
 add_executable(basic-vcs src/main.cpp
@@ -24,7 +32,10 @@ add_executable(basic-vcs src/main.cpp
         src/commands/hash-object.cpp
         include/hash-object.h
         src/commands/clone.cpp
-        include/clone.h)
+        include/clone.h
+        src/commands/commit-tree.cpp
+        include/commit-tree.h
+        include/commit-tree.h)
 
-target_link_libraries(basic-vcs zstr::zstr)
+target_link_libraries(basic-vcs PRIVATE zstr::zstr date::date date::date-tz)
 target_include_directories(basic-vcs PRIVATE include)

include/commit-tree.h

@@ -0,0 +1,3 @@
+#pragma once
+
+int commitTree(int argc, const char** argv);

src/commands/cat-file.cpp

@@ -28,6 +28,7 @@ int catFile(const int argc, const char** argv)
     const std::string file = input.substr(2);
 
     zstr::ifstream inputFile("./.git/objects/" + dir + "/" + file, std::ofstream::binary);
+
     if (!inputFile.is_open())
     {
         std::cerr << "Could not open file\n";
@@ -36,6 +37,7 @@ int catFile(const int argc, const char** argv)
 
     const std::string output{std::istreambuf_iterator<char>(inputFile), std::istreambuf_iterator<char>()};
     std::cout << std::string_view(output).substr(output.find('\0') + 1);
+
     inputFile.close();
 
     return 0;

src/commands/commit-tree.cpp

@@ -0,0 +1,127 @@
+#include "commit-tree.h"
+
+#include <iostream>
+#include <filesystem>
+#include <fstream>
+#include <string>
+#include <string_view>
+#include <chrono>
+
+#include "sha1.hpp"
+#include "zstr.hpp"
+#include "date/tz.h"
+
+int commitTree(int argc, const char** argv)
+{
+    const std::string_view firstFlag = argv[3];
+    if (firstFlag != "-m" and firstFlag != "-p")
+    {
+        std::cerr << "\n\nplease use '-p' to specify the parent commit, or '-m' to specify initial commit message" << "\n\n";
+        return 1;
+    }
+
+    bool initialCommit = false;
+    if (firstFlag == "-m")
+        initialCommit = true;
+
+    std::string commitHeader;
+    std::string commitBody;
+    std::string authorName;
+    std::string authorEmail;
+    std::string_view commitMessage;
+    std::string_view treeSha = argv[2];
+
+    commitBody.append("tree ");
+    commitBody.append(treeSha);
+    commitBody.append("\n");
+
+    if (!initialCommit)
+    {
+        const std::string_view parentSha = argv[4];
+        commitBody.append("parent ");
+        commitBody.append(parentSha).append("\n");
+        commitMessage = argv[6];
+    }
+    else
+    {
+        commitMessage = argv[4];
+    }
+
+    // get author info
+    if (std::filesystem::exists("./.git/author.txt"))
+    {
+        std::ifstream authorInfo("./.git/author.txt");
+        if (!authorInfo)
+        {
+            std::cerr << "\n\n'/.git/author.txt exists but could not be opened\n\n";
+            return 1;
+        }
+
+        //use getline() to include spaces between first and last name
+        std::getline(authorInfo, authorName);
+        std::getline(authorInfo, authorEmail);
+        authorInfo.close();
+    }
+    else
+    {
+        //use getline() to include spaces between first and last name
+        std::cout << "please enter the name of the author/commiter: ";
+        std::getline(std::cin, authorName);
+        std::cout << "please enter the email of the author/commiter: ";
+        std::getline(std::cin, authorEmail);
+
+        char input{};
+        do
+        {
+            std::cout << "would you like to save this information for future commits? (Y/N): ";
+            std::cin >> input;
+            input = std::toupper(input);
+        } while (input != 'Y' and input != 'N');
+
+        if (input == 'Y')
+        {
+            std::ofstream authorFile("./.git/author.txt");
+            if (!authorFile)
+            {
+                std::cerr << "\n\ncould not write author info to '/.git/author.txt'\n\n";
+                authorFile.close();
+            }
+            else
+            {
+                authorFile << authorName << "\n" << authorEmail << "\n";
+                authorFile.close();
+                std::cout << "successfully wrote author info to '/.git/author.txt\n";
+            }
+        }
+    }// end get author info
+
+    auto timeZoneLocal = date::make_zoned(date::current_zone(), std::chrono::system_clock::now());
+    std::ostringstream tzOffset;
+    tzOffset << timeZoneLocal.get_info().offset;
+
+    //assume commiter and author are the same
+    commitBody.append("author " + authorName + " <" + authorEmail + "> " + std::to_string(timeZoneLocal.get_local_time().time_since_epoch().count()) + " " + tzOffset.str().substr(0,5) + "\n") ;//use substr() to exclude the char that defines the unit of measurement
+    commitBody.append("commiter " + authorName + " <" + authorEmail + "> " + std::to_string(timeZoneLocal.get_local_time().time_since_epoch().count()) + " " + tzOffset.str().substr(0,5) + "\n\n") ;
+    commitBody.append(commitMessage);
+
+    commitHeader.append("commit " + std::to_string(commitBody.size()) + '\0');
+
+    std::string commitObject = commitHeader + commitBody;
+
+    SHA1 checksum;
+    checksum.update(commitObject);
+    const std::string hash = checksum.final();
+    const std::string hashDir = "./.git/objects/" + hash.substr(0,2);
+
+    if (!std::filesystem::exists(hashDir))
+    {
+        std::filesystem::create_directory(hashDir);
+    }
+
+    zstr::ofstream outputFile(hashDir + "/" + hash.substr(2));
+    outputFile.write(commitObject.c_str(), commitObject.size());
+
+    outputFile.close();
+
+    return 0;
+}

src/commands/hash-object.cpp

@@ -24,6 +24,7 @@ int hashObject(const int argc, const char** argv)
         std::cerr << flag << "is an invalid flag, please use \"-w\"\n";
         return 1;
     }
+
     const std::string path = argv[3];
     std::ifstream inputFile("./" + path);
     if (!inputFile.is_open())
@@ -40,9 +41,14 @@ int hashObject(const int argc, const char** argv)
     const std::string hash = checksum.final();
     std::cout << hash << "\n";
 
-    std::filesystem::create_directory("./.git/objects/" + hash.substr(0,2));
+    const std::string hashDir = "./.git/objects/" + hash.substr(0,2);
 
-    zstr::ofstream outputFile("./.git/objects/" + hash.substr(0,2) + "/" + hash.substr(2));
+    if (!std::filesystem::exists(hashDir))
+    {
+        std::filesystem::create_directory(hashDir);
+    }
+
+    zstr::ofstream outputFile(hashDir + "/" + hash.substr(2));
     outputFile.write(objectData.c_str(), objectData.size());
 
     inputFile.close();

src/commands/ls-tree.cpp

@@ -34,6 +34,7 @@ int lsTree(const int argc, const char** argv)
     }
 
     const std::string output{std::istreambuf_iterator<char>(inputFile), std::istreambuf_iterator<char>()};
+
     //start right after tree <size>\0
     size_t startChar = output.find('\0') + 1;
     size_t nextNullChar = output.find('\0', startChar);
@@ -59,16 +60,18 @@ int lsTree(const int argc, const char** argv)
             }
 
             for (const auto& value : hash)
-                std::printf("%02x", static_cast<unsigned char>(value)); // simpler solution
+                std::printf("%02x", static_cast<unsigned char>(value)); // easy way to display raw bytes as hex chars
 
             std::cout << "    ";
         }
+
         std::cout << name << "\n";
+
         startChar = nextNullChar + 21;
         nextNullChar = output.find('\0', startChar);
     }
 
     inputFile.close();
-    return 0;
 
+    return 0;
 }

src/commands/write-tree.cpp

@@ -16,27 +16,27 @@ struct node
     std::string hash;
 };
 
-uint8_t hexToRaw(char firstDigit, char secondDigit)
+uint8_t hexToRaw(const char firstDigit, const char secondDigit)
 {
     uint8_t result = 0;
     switch (firstDigit)
     {
-        case '0': result = 0; break;
+        case '0': result = 0x0; break;
-        case '1': result = 1 << 4; break;
+        case '1': result = 0x1 << 4; break;
-        case '2': result = 2 << 4; break;
+        case '2': result = 0x2 << 4; break;
-        case '3': result = 3 << 4; break;
+        case '3': result = 0x3 << 4; break;
-        case '4': result = 4 << 4; break;
+        case '4': result = 0x4 << 4; break;
-        case '5': result = 5 << 4; break;
+        case '5': result = 0x5 << 4; break;
-        case '6': result = 6 << 4; break;
+        case '6': result = 0x6 << 4; break;
-        case '7': result = 7 << 4; break;
+        case '7': result = 0x7 << 4; break;
-        case '8': result = 8 << 4; break;
+        case '8': result = 0x8 << 4; break;
-        case '9': result = 9 << 4; break;
+        case '9': result = 0x9 << 4; break;
-        case 'a': result = 10 << 4; break;
+        case 'a': result = 0xa << 4; break;
-        case 'b': result = 11 << 4; break;
+        case 'b': result = 0xb << 4; break;
-        case 'c': result = 12 << 4; break;
+        case 'c': result = 0xc << 4; break;
-        case 'd': result = 13 << 4; break;
+        case 'd': result = 0xd << 4; break;
-        case 'e': result = 14 << 4; break;
+        case 'e': result = 0xe << 4; break;
-        case 'f': result = 15 << 4; break;
+        case 'f': result = 0xf << 4; break;
         default: result = 0; break;
     }
 
@@ -72,7 +72,7 @@ std::string hashDir(const std::string& path)
     for (const auto& object : std::filesystem::directory_iterator(path))
     {
         if (object.is_directory())
-        {
+        {//recurse into the directory
             nodes.emplace_back(object.path().filename().string(), 40000, hashDir(object.path().string()));
         }
         else
@@ -82,7 +82,9 @@ std::string hashDir(const std::string& path)
 
             SHA1 checksum;
             checksum.update("blob " + std::to_string(fileContent.size()) + '\0' + fileContent);
+
             nodes.emplace_back(object.path().filename(), 100644, checksum.final());
+
             file.close();
         }
     }
@@ -102,14 +104,12 @@ std::string hashDir(const std::string& path)
             treeObject += static_cast<char>(byte);
         }
     }
-    auto temp = treeObject.size();
 
     treeObject = "tree " + std::to_string(treeObject.size()) + '\0' + treeObject;
+
     SHA1 checksum;
     checksum.update(treeObject);
-
     return checksum.final();
-
 }
 
 int writeTree(const char** argv)
@@ -125,16 +125,19 @@ int writeTree(const char** argv)
         if (object.path().filename() == ".git") continue;
 
         if (object.is_directory())
-        {
+        {//recurse into the directory
             nodes.emplace_back(object.path().filename().string(), 40000, hashDir(object.path().string()));
         }
         else
         {
             std::ifstream file(object.path().string());
             std::string fileContent {std::istreambuf_iterator<char>(file), std::istreambuf_iterator<char>()};
+
             SHA1 checksum;
             checksum.update("blob " + std::to_string(fileContent.size()) + '\0' + fileContent);
+
             nodes.emplace_back(object.path().filename(), 100644, checksum.final());
+
             file.close();
         }
 
@@ -164,9 +167,14 @@ int writeTree(const char** argv)
     const std::string hash = checksum.final();
     std::cout << hash << "\n";
 
-    std::filesystem::create_directory("./.git/objects/" + hash.substr(0,2));
+    const std::string hashDir = "./.git/objects/" + hash.substr(0,2);
 
-    zstr::ofstream outputFile("./.git/objects/" + hash.substr(0,2) + "/" + hash.substr(2));
+    if (!std::filesystem::exists(hashDir))
+    {
+        std::filesystem::create_directory(hashDir);
+    }
+
+    zstr::ofstream outputFile(hashDir + "/" + hash.substr(2));
     outputFile.write(treeObject.c_str(), treeObject.size());
 
     outputFile.close();

src/main.cpp

@@ -2,6 +2,7 @@
 #include <string_view>
 #include <sstream>
 #include "commands.h"
+#include "commit-tree.h"
 #include "../include/hash-object.h"
 
 int main(const int argc, const char** argv)
@@ -34,6 +35,10 @@ int main(const int argc, const char** argv)
     {
         return writeTree(argv);
     }
+    else if (command == "commit-tree")
+    {
+        return commitTree(argc, argv);
+    }
     else if (command == "clone")
     {
         return clone(argc, argv);