char *getenv(const char *name)
{
int offset;
char *_findenv();
return _findenv(name, &offset);
}
/*
* P1003.1-1996 implementation of getenv().
*/
char *getenv(const char *name) {
int ignore;
char *temp;
_environ_lock();
temp = _findenv(name, &ignore, 0);
_environ_unlock();
return temp;
}
/*
* setenv --
* Set the value of the environmental variable "name" to be
* "value". If rewrite is set, replace any current value.
*/
int setenv(const char *name, const char *value, int rewrite)
{
static char **alloced; /* if allocated space before */
register char *c;
int l_value, offset;
#if defined(MINGW32)
if (! environ_c)
environ_c = environ;
#endif
if (*value == '=') /* no `=' in value */
++value;
l_value = strlen(value);
if ((c = _findenv(name, &offset))) { /* find if already exists */
if (!rewrite)
return (0);
if (strlen(c) >= l_value) { /* old larger; copy over */
while ( (*c++ = *value++) );
return (0);
}
} else { /* create new slot */
register int cnt;
register char **p;
for (p = *p_environ, cnt = 0; *p; ++p, ++cnt);
if (alloced == *p_environ) { /* just increase size */
p = (char **)realloc((char *)(*p_environ),
(size_t)(sizeof(char *) * (cnt + 2)));
if (!p)
return (-1);
alloced = *p_environ = p;
}
else { /* get new space */
/* copy old entries into it */
p = malloc((size_t)(sizeof(char *) * (cnt + 2)));
if (!p)
return (-1);
memcpy(p, *p_environ, cnt * sizeof(char *));
alloced = *p_environ = p;
}
(*p_environ)[cnt + 1] = NULL;
offset = cnt;
}
for (c = (char *)name; *c && *c != '='; ++c); /* no `=' in name */
if (!((*p_environ)[offset] = /* name + `=' + value */
malloc((size_t)((int)(c - name) + l_value + 2))))
return (-1);
for (c = (*p_environ)[offset]; (*c = *name++) && *c != '='; ++c);
for (*c++ = '='; (*c++ = *value++); );
return (0);
}
/*
* unsetenv(name) --
* Delete environmental variable "name".
*/
void unsetenv(const char *name)
{
register char **p;
int offset;
#if defined(MINGW32)
if (! environ_c)
environ_c = environ;
#endif
while (_findenv(name, &offset)) /* if set multiple times */
for (p = &(*p_environ)[offset];; ++p)
if (!(*p = *(p + 1)))
break;
}
/*
* Based on the BSD4.4 call unsetenv().
*/
void _unsetenv(const char *name) {
int offset;
char **pp;
_environ_lock();
// unset environment variable
while(_findenv(name, &offset, 0)) { /* if set multiple times */
for(pp = &environ[offset];; ++pp) {
if(!(*pp = *(pp + 1))) {
break;
}
}
}
_environ_unlock();
return;
}
/*
* getenv --
* Returns ptr to value associated with name, if any, else NULL.
*/
char *getenv(const char *name)
{
int offset;
return (_findenv(name, &offset));
}
