efl/src/lib/evil/evil_stdlib.c

147 lines
3.6 KiB
C

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif /* HAVE_CONFIG_H */
#include <stdlib.h>
#include <stdio.h>
#include <io.h>
#include <direct.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <errno.h>
#include "evil_private.h"
/*
* Environment variable related functions
*
* int setenv (const char *name, const char *value, int overwrite);
* void unsetenv (const char *name);
*
*/
EVIL_API int
setenv(const char *name,
const char *value,
int overwrite)
{
char *old_name;
char *str;
size_t length;
int res;
if (!name || !*name)
return -1;
/* if '=' is found, return EINVAL */
if (strchr (name, '='))
{
errno = EINVAL;
return -1;
}
/* if name is already set and overwrite is 0, we exit with success */
old_name = getenv(name);
if (!overwrite && old_name)
return 0;
length = value ? strlen(value) : 0;
length += strlen(name) + 2;
str = (char *)malloc(length);
if (!str)
{
errno = ENOMEM;
return -1;
}
if (!value)
sprintf(str, "%s=", name);
else
sprintf(str, "%s=%s", name, value);
res = _putenv(str);
free(str);
return res;
}
EVIL_API int
unsetenv(const char *name)
{
return setenv(name, NULL, 1);
}
/*
* Files related functions
*
*/
EVIL_API char *
realpath(const char *file_name, char *resolved_name)
{
char *retname = NULL; /* we will return this, if we fail */
/* SUSv3 says we must set `errno = EINVAL', and return NULL,
* if `name' is passed as a NULL pointer.
*/
if (file_name == NULL)
errno = EINVAL;
/* Otherwise, `name' must refer to a readable filesystem object,
* if we are going to resolve its absolute path name.
*/
else if (access(file_name, 4) == 0)
{
/* If `name' didn't point to an existing entity,
* then we don't get to here; we simply fall past this block,
* returning NULL, with `errno' appropriately set by `access'.
*
* When we _do_ get to here, then we can use `_fullpath' to
* resolve the full path for `name' into `resolved', but first,
* check that we have a suitable buffer, in which to return it.
*/
if ((retname = resolved_name) == NULL)
{
/* Caller didn't give us a buffer, so we'll exercise the
* option granted by SUSv3, and allocate one.
*
* `_fullpath' would do this for us, but it uses `malloc', and
* Microsoft's implementation doesn't set `errno' on failure.
* If we don't do this explicitly ourselves, then we will not
* know if `_fullpath' fails on `malloc' failure, or for some
* other reason, and we want to set `errno = ENOMEM' for the
* `malloc' failure case.
*/
retname = malloc(_MAX_PATH);
}
/* By now, we should have a valid buffer.
* If we don't, then we know that `malloc' failed,
* so we can set `errno = ENOMEM' appropriately.
*/
if (retname == NULL)
errno = ENOMEM;
/* Otherwise, when we do have a valid buffer,
* `_fullpath' should only fail if the path name is too long.
*/
else if ((retname = _fullpath(retname, file_name, _MAX_PATH)) == NULL)
errno = ENAMETOOLONG;
}
/* By the time we get to here,
* `retname' either points to the required resolved path name,
* or it is NULL, with `errno' set appropriately, either of which
* is our required return condition.
*/
return retname;
}