support for alias builtin

main.c

@@ -16,8 +16,11 @@ int get_alias(Alias *alias, State *state, char *name) {
 
 int add_alias(State* state, char *name, char *substitution) {
     Alias alias;
-    alias.name = name;
-    alias.substitution = substitution;
+    strip_char(name, ' ');
+    alias.name = calloc(strlen(name) + 1, sizeof(char));
+    alias.substitution = calloc(strlen(substitution) + 1, sizeof(char));
+    strcpy(alias.name, name);
+    strcpy(alias.substitution, substitution);
     Alias throw;
 
     if (get_alias(&throw, state, name)) {
@@ -54,7 +57,6 @@ int del_alias(State *state, char *name) {
     } else {
         return ER_FAILURE;
     }
-
 }
 
 int list_aliases(State *state) {
@@ -68,7 +70,8 @@ int list_aliases(State *state) {
 int check_builtins(State *state, int num_args, char *args[]) {
     char *builtins[NUM_BUILTINS] = {
         "cd",
-        "alias"
+        "alias",
+        "unalias"
     };
     
      if (!strcmp(args[0], "cd")) {
@@ -93,15 +96,16 @@ int check_builtins(State *state, int num_args, char *args[]) {
              return ER_SUCCESS;
          }
          // add new alias
-         if (num_args == 2) {
-             if (!get_alias(&alias, state, args[1])) {
-                 printf("alias %s=%s\n", alias.name, alias.substitution);
-                 return ER_SUCCESS;
-             } 
-             if (num_args > 1) {
+         if (num_args >= 2) {
+             if (num_args == 2) {
+                 if (!get_alias(&alias, state, args[1])) {
+                     printf("alias %s=%s\n", alias.name, alias.substitution);
+                     return ER_SUCCESS;
+                 } 
+             } else {
                  char *substitution;
                  char **new_split;
-                 int err = join_stirng(&substitution, num_args - 1, args + 1, " ");
+                 int err = join_string(&substitution, num_args - 1, args + 1, " ");
                  if (err) {
                      return err;
                  }
@@ -120,9 +124,28 @@ int check_builtins(State *state, int num_args, char *args[]) {
          }
      }
 
+    if (!strcmp(args[0], "unalias")) {
+        Alias alias;
+        if (num_args == 2) {
+             if (!del_alias(state, args[1])) {
+                 return ER_SUCCESS;
+            }
+        }
+    }
+
     return ER_FAILURE;
 }
 
+int check_aliases(State *state, char **substitution, char *name) {
+    Alias alias;
+    for (int i = 0; i < state->num_aliases; i++) {
+        if (!get_alias(&alias, state, name)) {
+            *substitution = alias.substitution;
+            return ER_SUCCESS;
+        }
+    }
+    return ER_FAILURE;
+}
 
 int run_command(State *state, int argc, char *argv[]) {
     pid_t child;
@@ -130,6 +153,28 @@ int run_command(State *state, int argc, char *argv[]) {
     if (argc == 0) {
         return ER_FAILURE;
     }
+    char *substitution;
+
+    if (!check_aliases(state, &substitution, argv[0])) {
+        strip_char(argv[0], ' ');
+        argv[0] = reallocarray(argv[0], strlen(substitution) + 1, sizeof(char));
+        strcpy(argv[0], substitution);
+        char *joined;
+        char **new_argv;
+        int len;
+        join_string(&joined, argc, argv, " ");
+        split_string(&new_argv, &len, joined, ' ');
+
+        //run_command(state, len, new_argv);
+        execute(stdin, stdout, new_argv, &child);
+        waitpid(child, NULL, 0);
+        return ER_SUCCESS;
+
+       for (int i = 0 ; i < len; i ++) {
+            free(new_argv[i]);
+        }
+        free(new_argv);
+    }
 
     if (check_builtins(state, argc, argv)) {
         execute(stdin, stdout, argv, &child);
@@ -176,7 +221,7 @@ int main(int argc, char** argv) {
       "           |\n",
       "          _|}\n"};
 
-    State *state = calloc(1, sizeof(state));
+    State *state = calloc(1, sizeof(State));
     state->aliases = calloc(INITIAL_NUM_ALIASES, sizeof(struct Alias));
     state->num_aliases = 0;
 

main.h

@@ -14,7 +14,7 @@
 #define INITIAL_WORD_SIZE 80
 #define INITIAL_NUM_ALIASES 50
 
-#define NUM_BUILTINS 2
+#define NUM_BUILTINS 3
 
 struct Alias {
     char *name;

util.c

@@ -35,7 +35,7 @@ int readline(FILE* in, char **out) {
 }
 
 /* Join an array of strings together using the delim string as the joiner. */
-int join_stirng(char **joined, int arr_len, char *sep_stirng[], char *delim) {
+int join_string(char **joined, int arr_len, char *sep_stirng[], char *delim) {
     int length = 0;
     int delim_len = strlen(delim);
 
@@ -68,6 +68,38 @@ int join_stirng(char **joined, int arr_len, char *sep_stirng[], char *delim) {
     return ER_FAILURE;
 }
 
+int strip_char(char *string, char del) {
+    int len = strlen(string);
+    bool move = false;
+
+    for (int i = 0; i < len; i++) {
+        if (move && i != len-1) {
+            string[i] = string[i + 1];
+        } else if (move) {
+            string[i] ='\0';
+        }
+
+        if (string[i] == del) {
+            move = true;
+            len -= 1;
+            if (move && i != len-1) {
+                string[i] = string[i + 1];
+            } else if (move) {
+                string[i] ='\0';
+            }
+        }
+    }
+
+    if (!move) {
+        return ER_SUCCESS;
+    } else {
+        strip_char(string, del);
+    }
+
+    return ER_FAILURE;
+}
+
+
 /* Take a string and split it into an array of strings, separate by the delim
  * character.
  */

util.h

@@ -8,6 +8,8 @@ int readline(FILE* in, char **out);
 
 int split_string(char **sep_string[], int *num, char *string, char delim); 
 
-int join_stirng(char **joined, int arr_len, char *sep_stirng[], char *delim); 
+int join_string(char **joined, int arr_len, char *sep_stirng[], char *delim); 
+
+int strip_char(char *string, char del);
 
 #endif