From ac6dbe8cd73de0243841d1df990c5d09956f65af Mon Sep 17 00:00:00 2001
From: stitchy <stitchy@stitchy.moe>
Date: Thu, 9 Nov 2023 11:07:32 +0000
Subject: [PATCH] commiting_from_my_own_personal_shell

---
 smallsh/main.c   | 92 ++++++++++++++++++++++++++++++++++++++++++++++++
 smallsh/main.h   | 15 ++++++++
 smallsh/makefile | 17 +++++++++
 smallsh/node.c   | 62 ++++++++++++++++++++++++++++++++
 smallsh/node.h   | 24 +++++++++++++
 5 files changed, 210 insertions(+)
 create mode 100644 smallsh/main.c
 create mode 100644 smallsh/main.h
 create mode 100644 smallsh/makefile
 create mode 100644 smallsh/node.c
 create mode 100644 smallsh/node.h

diff --git a/smallsh/main.c b/smallsh/main.c
new file mode 100644
index 0000000..fbd9ddc
--- /dev/null
+++ b/smallsh/main.c
@@ -0,0 +1,92 @@
+#include "main.h"
+
+int main() {
+
+  int status = 0;
+  size_t input_size = 2048;
+  size_t getline_len;
+  char* input = malloc(sizeof(char) * input_size);
+
+  while(1) {
+    printf(": ");
+    fflush(stdout);
+    getline_len = getline(&input, &input_size, stdin);
+    input[getline_len - 1] = '\0';
+
+    // Ignore whitespace or comments
+    if(input == NULL ||
+       input[0] == '#') {
+      continue;
+    }
+
+
+    char*** array = malloc(sizeof(char**));
+    int num_strings = input_format(input, input_size, array);
+
+    char* first_array = (*array)[0];
+
+    // Built in shell commands
+    if(!strncmp(first_array, "exit", 4))
+        return 0;
+    else if(!strncmp(first_array, "cd", 2))
+      inbuilt_cd((*array)[1]);
+    else if (!strncmp(first_array, "status", 6))
+      printf("%d\n", status);
+    else
+      status = run_command(array, num_strings);
+    fflush(stdout);
+
+  }
+}
+
+int input_format(char* input, size_t input_size, char*** array) {
+
+  const int max_args = 512;
+  int num_strings = 0;
+  char* pch;
+  *array = malloc(sizeof(char*) * max_args);
+
+  pch = strtok (input," ");
+  while (pch != NULL)
+  {
+    (*array)[num_strings] = malloc(sizeof(char*) * (strlen(pch) + 1));
+    strcpy((*array)[num_strings], pch);
+    num_strings++;
+
+    pch = strtok (NULL, " ");
+  }
+
+  return num_strings;
+}
+
+void inbuilt_cd(char* args) {
+
+  if(args)
+    chdir(args);
+  else
+    chdir(getenv("HOME"));
+
+}
+
+int run_command(char*** array, int num_array) {
+
+  char* comb_string = malloc(sizeof(char) * 100);
+  sprintf(comb_string, "/usr/bin/");
+  strcat(comb_string, (*array)[0]);
+  int f = fork();
+  pid_t pid;
+  if(!f) 
+    pid = execv(comb_string, (*array));
+
+  int status;
+  waitpid(pid, &status, 0);
+
+  free(comb_string);
+
+  return status;
+
+}
+
+
+
+
diff --git a/smallsh/main.h b/smallsh/main.h
new file mode 100644
index 0000000..1795bdf
--- /dev/null
+++ b/smallsh/main.h
@@ -0,0 +1,15 @@
+
+#ifndef MAIN
+#define MAIN
+
+#include "stdlib.h"
+#include "stdio.h"
+#include "string.h"
+#include "unistd.h"
+#include "sys/wait.h"
+
+int input_format(char*, size_t, char***);
+void inbuilt_cd(char*);
+int run_command(char***, int);
+
+#endif 
diff --git a/smallsh/makefile b/smallsh/makefile
new file mode 100644
index 0000000..27130ea
--- /dev/null
+++ b/smallsh/makefile
@@ -0,0 +1,17 @@
+CC=gcc --std=gnu99 -g
+output=smallsh
+
+all: main.c main.h node.o input.o
+	$(CC) main.c node.o input.o -o $(output)
+
+node.o: node.c node.h
+	$(CC) -c node.c -o node.o
+
+input.o: input.h input.c
+	$(CC) -c input.c -o input.o
+
+test: all
+	./p3testscript
+
+clean:
+	rm -fr *.o vgcore.* $(output)
diff --git a/smallsh/node.c b/smallsh/node.c
new file mode 100644
index 0000000..698180c
--- /dev/null
+++ b/smallsh/node.c
@@ -0,0 +1,62 @@
+
+#include "node.h"
+
+void append_node(struct node* head, struct node* node_app) {
+	
+  if(!head) {
+    head = node_app;
+    return;
+  }
+
+  struct node* temp = head;
+
+  while(temp->node != NULL) {
+    temp = temp->node;
+  }
+  temp->node = node_app;
+  
+} 
+
+struct node* appendv_node(struct node* head, void* data) {
+
+  struct node* node = malloc(sizeof(struct node));
+  node->data = data;
+  node->node = NULL;
+
+  append_node(head, node);
+
+  return node;
+}
+
+int count_nodes(struct node* head) {
+
+  int num = 1;
+
+  if(!head)
+    return -1;
+
+  struct node* temp = head;
+  while(temp->node) {
+
+    temp = temp->node;
+    num++;
+  }
+  
+  return num;
+}
+
+void iterate_nodes(struct node* head, void *func (void*, void*), void* val) {
+
+  if(!head)
+    return;
+
+  func(head->data, val);
+
+  struct node* temp = head;
+
+  while(temp->node) {
+    temp = temp->node;
+    func(temp->data, val);
+  }
+}
+
diff --git a/smallsh/node.h b/smallsh/node.h
new file mode 100644
index 0000000..71f4d6d
--- /dev/null
+++ b/smallsh/node.h
@@ -0,0 +1,24 @@
+#include "stdlib.h"
+
+#ifndef NODES
+#define NODES
+
+struct node {
+  struct node* node;
+  void* data;
+};
+
+// Appends Node to list
+void append_node(struct node*, struct node*);
+
+// Creates node with value and appends
+// Returns node that was created
+struct node* appendv_node(struct node*, void*);
+
+// Counts the number of nodes in a list
+int count_nodes(struct node*);
+
+// Iterates over every node in a list and runs the given function
+void iterate_nodes(struct node*, void *func(void*, void*), void*);
+
+#endif