final_1

main.c

@@ -5,23 +5,142 @@
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <termios.h>
 
 #define MAX_SIZE 1024
+#define HISTORY_SIZE 5
 
-// int LogCommandHistory(char* buf, char** command_log, int n) {
-//     command_log[n] = buf;
-// }
+// RAW TERMINAL INPUT / LOGGING HISTORY IMPLEMENTATION -----------
 
-void PrintCurrentDir() { // pwd
+// Global variable for termios
+struct termios orig_termios;
+
+// Termios functions
+void EnableRawMode(struct termios* orig_termios) {
+    struct termios raw = *orig_termios;
+    raw.c_lflag &= ~(ECHO | ICANON);
+    tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw);
+}
+
+void DisableRawMode(struct termios* orig_termios) {
+    tcsetattr(STDIN_FILENO, TCSAFLUSH, orig_termios);
+}
+
+void DisableRawModeWrapper() {
+    DisableRawMode(&orig_termios);
+}
+
+int LogCommandHistory(char* buf, char** command_log, int* n) {
+    int index = *n % HISTORY_SIZE;
+    int prev_index = (*n == 0) ? HISTORY_SIZE - 1 : (*n - 1) % HISTORY_SIZE;
+
+    if (command_log[prev_index] != NULL && strcmp(buf, command_log[prev_index]) == 0) {
+        return 0;
+    }
+    if (command_log[index] != NULL) {
+        free(command_log[index]);
+    }
+
+    command_log[index] = strdup(buf);
+    (*n)++;
+
+    return 0;
+}
+
+void FreeCommandHistory(char** command_log, int n) {
+    for (int i = 0; i < n; i++) {
+        free(command_log[i]);
+    }
+}
+
+void ClearBufferContent(int length) { // Function to clear buffer
+    for (int i = 0; i < length; i++) {
+        printf("\b \b");
+    }
+}
+
+// Get raw input from terminal + arrow key history navigation
+void GetRawInput(char* buf, char** command_log, int n) {
+    int index = n % HISTORY_SIZE;
+    int history_counter = 0;
+    int pos = 0;
+    char c;
+
+    while (1) {
+        c = getchar();
+
+        if (c == '\n') { // Enter key
+            buf[pos] = '\0';
+            printf("\n");
+            return;
+        } else if (c == 127 || c == '\b') { // Backspace
+            if (pos > 0) {
+                pos--;
+                buf[pos] = '\0';
+                printf("\b \b");
+            }
+        } else if (c == '\033') { // Inputting arrow keys
+            getchar(); // Skip '[' character
+            char arrow = getchar();
+
+            if (arrow == 'A') { // Up arrow
+                int prev_index = (index == 0) ? HISTORY_SIZE - 1 : (index - 1) % HISTORY_SIZE;
+                if (command_log[prev_index] != NULL) {
+                    ClearBufferContent(pos); // Clear current buffer
+                    index = (index == 0) ? HISTORY_SIZE - 1 : index - 1;
+                    history_counter++;
+
+                    strcpy(buf, command_log[index]);
+                    printf("%s", buf);
+                    pos = strlen(buf);
+                }
+            }
+            else if (arrow == 'B') { // Down arrow
+                if (history_counter > 0) {
+                    index = (index + 1) % HISTORY_SIZE;
+                    history_counter--;
+                    ClearBufferContent(pos);
+                    if (history_counter == 0) {
+                        buf[0] = '\0'; // Clear buffer
+                        pos = 0;
+                    } else {
+                        strcpy(buf, command_log[index]);
+                        printf("%s", buf);
+                        pos = strlen(buf);
+                    }
+                }
+            }
+        } else { // Regular character
+            if (pos < MAX_SIZE - 1) {
+                buf[pos++] = c;
+                buf[pos] = '\0';
+                printf("%c", c);
+            }
+        }
+    }
+}
+
+
+// MAIN MICROSHELL FUNCTIONS -----------
+
+char* GetCurrentUserAndDir() { // return current user + working directory
     char cwd[MAX_SIZE];
     if (getcwd(cwd, sizeof(cwd)) == NULL) {
         perror("getcwd() error");
+        return NULL;
     }
     char* user = getenv("USER");
     if (user == NULL) {
         perror("getenv() error");
+        return NULL;
     }
-    printf("[%s@%s] $ ", user, cwd);
+
+    size_t result_size = strlen(user) + strlen(cwd) + 7; // Allocate memory (include extra space for format characters)
+    char* result = (char*)malloc(result_size);
+
+    snprintf(result, result_size, "[%s@%s] $ ", user, cwd); // Format the prompt string
+
+    return result;
 }
 
 int ChangeDirectory(char** args) { // cd
@@ -38,14 +157,12 @@ int ChangeDirectory(char** args) { // cd
 }
 
 void PrintHelp() { // help 
-    printf("-------------------------------------------------");
+    printf("-------------------------------------------------\n");
     printf("C Microshell implementation by Maciej Życzyński\n");
-    printf("\"exit\" - exit the program");
-    printf("\"help\" - display this menu");
-    printf("Other bash commands work accordingly in child processes");
-    printf("Currently logged user / working directory:");
-    PrintCurrentDir();
-    printf("-------------------------------------------------");
+    printf("\"exit\" - exit the program\n");
+    printf("\"help\" - display this menu\n");
+    printf("Other bash commands work accordingly in child processes\n");
+    printf("-------------------------------------------------\n");
 }
 
 int HandleBuiltInCommands(char* command, char** args) { // Manual implementation of commands unsupported by execvp()
@@ -71,10 +188,9 @@ int HandleCommand(char* command, char** args) { // Execute commands supported by
     return 0;
 }
 
-int ParseCommand(char* buf, char** command, char** args) {
+int ParseCommand(char* buf, char** command, char** args) { // Parse input string into command and array of arguments
     char buf_cp[MAX_SIZE];
     strcpy(buf_cp, buf); // Leave the original buffer (important for command history implementation)
-    buf_cp[strlen(buf_cp) - 1] = '\0'; // Remove newline from input string
 
     char* token = strtok(buf_cp, " ");
     int tok_count = 0;
@@ -94,25 +210,39 @@ int ParseCommand(char* buf, char** command, char** args) {
     return 0;
 }
 
+
 int main() {
     char buf[MAX_SIZE];
-    char* command_log[MAX_SIZE];
+    char* command;
+    char* args[MAX_SIZE];
     int n = 0;
+    char* command_log[HISTORY_SIZE] = {NULL};
+    
+    // Save original terminal settings and restore them on exit
+    if (tcgetattr(STDIN_FILENO, &orig_termios) == -1) {
+        perror("tcgetattr() error");
+        return 1;
+    }
+    atexit(DisableRawModeWrapper); // call DisableRawModeWrapper when program exits
 
     while (1) {
-        PrintCurrentDir();
+        char* prompt = GetCurrentUserAndDir(); // Display prompt
+        if (prompt != NULL) {
+            printf("%s", prompt);
+            free(prompt);
+        }
 
-        char* command;
-        char* args[MAX_SIZE];
-        fgets(buf, sizeof(buf), stdin);
+        EnableRawMode(&orig_termios);
+        GetRawInput(buf, command_log, n);
+        DisableRawMode(&orig_termios);
         
-        if (ParseCommand(buf, &command, args) < 0) {
+
+        if (ParseCommand(buf, &command, args) < 0) { // Parse buffer input
             printf("Invalid command\n");
             continue;
         }
 
-        // LogCommandHistory(buf, &command_log, n);
-        // n++;
+        LogCommandHistory(buf, command_log, &n); // Add buffer to logging history
 
         int handler_value = HandleBuiltInCommands(command, args);
         if (handler_value == 2) { // Exit command
@@ -140,5 +270,6 @@ int main() {
         }
     }
 
+    FreeCommandHistory(command_log, n);
     return 0;
 }