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env_builtins.c
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env_builtins.c
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#include "shell.h"
int shellby_env(char **args, char __attribute__((__unused__)) **front);
int shellby_setenv(char **args, char __attribute__((__unused__)) **front);
int shellby_unsetenv(char **args, char __attribute__((__unused__)) **front);
/**
* shellby_env - Prints the current environment.
* @args: An array of arguments passed to the shell.
* @front: A double pointer to the beginning of args.
*
* Return: If an error occurs - -1.
* Otherwise - 0.
*
* Description: Prints one variable per line in the
* format 'variable'='value'.
*/
int shellby_env(char **args, char __attribute__((__unused__)) **front)
{
int index;
char nc = '\n';
if (!environ)
return (-1);
for (index = 0; environ[index]; index++)
{
write(STDOUT_FILENO, environ[index], _strlen(environ[index]));
write(STDOUT_FILENO, &nc, 1);
}
(void)args;
return (0);
}
/**
* shellby_setenv - Changes or adds an environmental variable to the PATH.
* @args: An array of arguments passed to the shell.
* @front: A double pointer to the beginning of args.
* Description: args[1] is the name of the new or existing PATH variable.
* args[2] is the value to set the new or changed variable to.
*
* Return: If an error occurs - -1.
* Otherwise - 0.
*/
int shellby_setenv(char **args, char __attribute__((__unused__)) **front)
{
char **env_var = NULL, **new_environ, *new_value;
size_t size;
int index;
if (!args[0] || !args[1])
return (create_error(args, -1));
new_value = malloc(_strlen(args[0]) + 1 + _strlen(args[1]) + 1);
if (!new_value)
return (create_error(args, -1));
_strcpy(new_value, args[0]);
_strcat(new_value, "=");
_strcat(new_value, args[1]);
env_var = _getenv(args[0]);
if (env_var)
{
free(*env_var);
*env_var = new_value;
return (0);
}
for (size = 0; environ[size]; size++)
;
new_environ = malloc(sizeof(char *) * (size + 2));
if (!new_environ)
{
free(new_value);
return (create_error(args, -1));
}
for (index = 0; environ[index]; index++)
new_environ[index] = environ[index];
free(environ);
environ = new_environ;
environ[index] = new_value;
environ[index + 1] = NULL;
return (0);
}
/**
* shellby_unsetenv - Deletes an environmental variable from the PATH.
* @args: An array of arguments passed to the shell.
* @front: A double pointer to the beginning of args.
* Description: args[1] is the PATH variable to remove.
*
* Return: If an error occurs - -1.
* Otherwise - 0.
*/
int shellby_unsetenv(char **args, char __attribute__((__unused__)) **front)
{
char **env_var, **new_environ;
size_t size;
int index, index2;
if (!args[0])
return (create_error(args, -1));
env_var = _getenv(args[0]);
if (!env_var)
return (0);
for (size = 0; environ[size]; size++)
;
new_environ = malloc(sizeof(char *) * size);
if (!new_environ)
return (create_error(args, -1));
for (index = 0, index2 = 0; environ[index]; index++)
{
if (*env_var == environ[index])
{
free(*env_var);
continue;
}
new_environ[index2] = environ[index];
index2++;
}
free(environ);
environ = new_environ;
environ[size - 1] = NULL;
return (0);
}