Merge pull request #2 from Demidorn/demi

Demi

Author: lmuleke

DL_envs.c

@@ -0,0 +1,124 @@
+#include "header.h"
+
+/**
+ * prog_setenv - Modifies an environment variable to the path
+ * @args: An array of arguments
+ * @ard: Double pointer to arguments
+ *
+ * Return: 1 if error occurs otherwise 0
+ */
+
+int prog_setenv(char **args, char __attribute__((__unused__)) **ard)
+{
+	char **old_value = NULL, *new_value, **new_env;
+	size_t size = 0;
+	int start;
+
+	if (!args[0] || !args[1])
+		_error(args[0], -1);
+	new_value = malloc((_strlen(args[0]) + 1) + (_strlen(args[1]) + 1));
+	if (!new_value)
+		_error(args[0], -1);
+	_strcpy(new_value, args[0]);
+	_strcat(new_value, "=");
+	_strcat(new_value, args[1]);
+	old_value = _getenv(args[0]);
+	if (old_value)
+	{
+		free(*old_value);
+		*old_value = new_value;
+		return (0);
+	}
+
+	while (environ[size])
+		size++;
+	new_env = malloc(sizeof(char *) * (size + 2));
+	if (!new_env)
+	{
+		free(new_value);
+		_error(args[0], -1);
+	}
+	for (start = 0; environ[start]; start++)
+		new_env[start] = environ[start];
+	free(environ);
+	environ = new_env;
+	environ[start] = new_value;
+	environ[start + 1] = NULL;
+	return (0);
+}
+
+/**
+ * prog_unsetenv - Deletes an environment variable from the path
+ * @args: Array of arguments
+ * @ard: Double pointer arguments
+ *
+ * Return: -1 if error occurs otherwise 0
+ */
+
+int prog_unsetenv(char **args, char __attribute__((__unused__)) **ard)
+{
+	char **env_var, **new_env;
+	size_t start = 0;
+	int i, j;
+
+	i = j = 0;
+	if (!args[0])
+		_error(args[0], -1);
+	env_var = _getenv(args[0]);
+	if (!env_var)
+		return (0);
+
+	while (environ[start])
+		start++;
+	new_env = malloc(sizeof(char *) * start);
+	if (!new_env)
+		_error(args[0], -1);
+
+	while (environ[i])
+	{
+		if (*env_var == environ[i])
+		{
+			free(*env_var);
+			continue;
+		}
+		new_env[j] = environ[i];
+		i++;
+		j++;
+	}
+	free(environ);
+	environ = new_env;
+	environ[start - 1] = NULL;
+	return (0);
+}
+
+/**
+ * _printenv - prints path to the environment variable
+ *
+ * Return: ....
+ */
+
+void _printenv(void)
+{
+	char **env = environ;
+	
+	while (*env != NULL)
+	{
+		print_env_variable(*env);
+		env++;
+	}
+}
+
+/**
+ * print_env_variable - displays output of the environment variable
+ * @str: string that holds the outputted env variable
+ *
+ * Return: ...
+ */
+
+void print_env_variable(const char *str)
+{
+	size_t len = _strlen(str);
+
+	write(STDOUT_FILENO, str, len);
+	write(STDOUT_FILENO, "\n", 1);
+}

DL_error.c

@@ -0,0 +1,31 @@
+#include "header.h"
+
+/**
+ * _error - writes error message to sdterr
+ * @args: array of arguments
+ * @error_msg: error
+ *
+ * Return: Error
+ */
+
+void _error(const char *args, int error_msg)
+{
+	char *buffer = (char *)malloc(sizeof(char));
+	char str_error[100];
+
+	if (access(args, F_OK) != 0)
+	{
+		strcpy(buffer, "File not found\n");
+	}
+	else
+	{
+		strcpy(buffer, "Error: ");
+		strcat(buffer, args);
+		strcat(buffer, ", Error_msg: ");
+		int_to_string(error_msg, str_error);
+		strcat(buffer, str_error);
+		strcat(buffer, "\n");
+	}
+	write(STDERR_FILENO, buffer, strlen(buffer));
+	free(buffer);
+}

DL_execute.c

@@ -0,0 +1,41 @@
+#include "header.h"
+
+/**
+ * _execute - code that executes the execve commands
+ * @args: pointer to string array
+ * @envp: array to pointer of environment variable
+ *
+ * Return: 0 successful
+ */
+
+int _execute(char *args, char **envp)
+{
+	char **argv;
+	/*int kai;*/
+	struct stat buff;
+
+	argv = malloc(sizeof(char *));
+	if (argv == NULL)
+	{
+		perror("Error: ");
+		exit(EXIT_FAILURE);
+	}
+	argv[0] = strtok(args, " \t\n");
+	if (argv[0] == NULL)
+	{
+		free(argv);
+		return (0);
+	}
+	/*check if file exists*/
+	if (stat(argv[0], &buff) == -1)
+	{
+		perror("Error: ");
+		free(argv);
+		exit(EXIT_FAILURE);
+	}
+	execve(argv[0], argv, envp);
+	/*print error if execve failed*/
+	perror("Error execve:");
+	free(argv);
+	exit(EXIT_FAILURE);
+}

DL_getenv.c

@@ -0,0 +1,22 @@
+#include "header.h"
+
+/**
+ * _getenv - gets an env variable from the path
+ * @str: name of the variable to get
+ *
+ * Return: pointer to the env variable else null
+ */
+
+char **_getenv(const char *str)
+{
+	int lens, j;
+
+	lens = _strlen((char *)str);
+
+	for (j = 0; environ[j]; j++)
+	{
+		if (_strncmp(str, environ[j], lens) == 0)
+			return (&environ[j]);
+	}
+	return (NULL);
+}

DL_getline.c

@@ -0,0 +1,46 @@
+#include "header.h"
+
+/**
+ * _getline - reads line from standard imput
+ *
+ * Return: ouput from stdin
+ */
+
+char *_getline()
+{
+	int buffer = BUFFER_SIZE;
+	char *str = malloc(buffer);
+	int i = 0, c;
+
+	if (!str)
+	{
+		perror("Error ");
+		return (NULL);
+	}
+
+	while (1)
+	{
+		c = getchar();
+		if (c == EOF || c == '\n')
+		{
+			str[i] = '\0';
+			break;
+		}
+		else
+		{
+			str[i] = c;
+			i++;
+			if ((i >= buffer) == 1)
+			{
+				buffer += BUFFER_SIZE;
+				str = realloc(str, buffer);
+				if (!str)
+				{
+					perror("Error");
+					return (NULL);
+				}
+			}
+		}
+	}
+	return (str);
+}

DL_locator.c

@@ -0,0 +1,53 @@
+#include "header.h"
+
+/**
+ * locate_path - checks for path of the variable executed
+ * @com_val: Pointer to string values
+ *
+ * Return: 0 when successful otherwise -1
+ */
+
+char *locate_path(char *com_val)
+{
+	char *read_path, *copy_of_path, *file = NULL;
+	char *token_to_path;
+	size_t length, dir_length;
+	struct stat buff;
+
+	if (stat(com_val, &buff) == 0)
+		return (strdup(com_val));
+	read_path = getenv("PATH");
+	if (!read_path)
+		return (NULL);
+	copy_of_path = strdup(read_path);
+	if (!copy_of_path)
+		return (NULL);
+	token_to_path = strtok(copy_of_path, ";");
+
+	while (token_to_path != NULL)
+	{
+		dir_length = strlen(tken_to_path);
+		length = strlen(com_val);
+		file = malloc(length + dir_length + 2);
+		if (!file)
+		{
+			free(copy_of_path);
+			return (NULL);
+		}
+		strcpy(file, token_to_path);
+		strcat(file, "/");
+		strcat(file, com_val);
+		if (stat(file, &buff) == 0)
+		{
+			free(copy_of_path);
+			return (file);
+		}
+		else
+		{
+			free(file);
+			token_to_path = strtok(NULL, ":");
+		}
+	}
+	free(copy_of_path);
+	return (NULL);
+}