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| | #include <unistd.h>
#include <errno.h>
#include <limits.h>
#include <string.h>
#include "syscall.h"
#include "libc.h"
static char *do_getcwd(char *buf, size_t size)
{
long ret = syscall(SYS_getcwd, buf, size);
if (ret < 0)
return 0;
if (ret == 0 || buf[0] != '/') {
errno = ENOENT;
return 0;
}
return buf;
}
static char *getcwd_glibc(size_t size)
{
char tmp[PATH_MAX];
if (!do_getcwd(tmp, sizeof tmp))
return 0;
size_t len = strlen(tmp) + 1;
if (!size)
size = len;
else if (size < len) {
errno = ERANGE;
return 0;
}
char *buf = malloc(size);
if (!buf) {
errno = ENOMEM;
return 0;
}
memcpy(buf, tmp, len);
return buf;
}
char *getcwd(char *buf, size_t size)
{
if (!buf)
return getcwd_glibc(size);
if (!size) {
errno = EINVAL;
return 0;
}
return do_getcwd(buf, size);
}
|