+\f
+/*
+ * getpwuid() stuff
+ */
+
+#ifndef LISP_FEATURE_WIN32
+/* Return a newly-allocated string holding the username for "uid", or
+ * NULL if there's no such user.
+ *
+ * KLUDGE: We also return NULL if malloc() runs out of memory
+ * (returning strdup() result) since it's not clear how to handle that
+ * error better. -- WHN 2001-12-28 */
+char *
+uid_username(int uid)
+{
+ struct passwd *p = getpwuid(uid);
+ if (p) {
+ /* The object *p is a static struct which'll be overwritten by
+ * the next call to getpwuid(), so it'd be unsafe to return
+ * p->pw_name without copying. */
+ return strdup(p->pw_name);
+ } else {
+ return 0;
+ }
+}
+
+char *
+uid_homedir(uid_t uid)
+{
+ struct passwd *p = getpwuid(uid);
+ if(p) {
+ /* Let's be careful about this, shall we? */
+ size_t len = strlen(p->pw_dir);
+ if (p->pw_dir[len-1] == '/') {
+ return strdup(p->pw_dir);
+ } else {
+ char *result = malloc(len + 2);
+ if (result) {
+ int nchars = sprintf(result,"%s/",p->pw_dir);
+ if (nchars == len + 1) {
+ return result;
+ } else {
+ return 0;
+ }
+ } else {
+ return 0;
+ }
+ }
+ } else {
+ return 0;
+ }
+}
+#endif /* !LISP_FEATURE_WIN32 */
+\f
+/*
+ * functions to get miscellaneous C-level variables
+ *
+ * (Doing this by calling functions lets us borrow the smarts of the C
+ * linker, so that things don't blow up when libc versions and thus
+ * variable locations change between compile time and run time.)
+ */
+
+char **
+wrapped_environ()
+{
+ return environ;
+}
+
+#ifdef LISP_FEATURE_WIN32
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <time.h>
+/*
+ * faked-up implementation of select(). Right now just enough to get through
+ * second genesis.
+ */
+int select(int top_fd, DWORD *read_set, DWORD *write_set, DWORD *except_set, time_t *timeout)
+{
+ /*
+ * FIXME: Going forward, we may want to use MsgWaitForMultipleObjects
+ * in order to support a windows message loop inside serve-event.
+ */
+ HANDLE handles[MAXIMUM_WAIT_OBJECTS];
+ int fds[MAXIMUM_WAIT_OBJECTS];
+ int num_handles;
+ int i;
+ DWORD retval;
+ int polling_write;
+ DWORD win_timeout;
+
+ num_handles = 0;
+ polling_write = 0;
+ for (i = 0; i < top_fd; i++) {
+ if (except_set) except_set[i >> 5] = 0;
+ if (write_set && (write_set[i >> 5] & (1 << (i & 31)))) polling_write = 1;
+ if (read_set[i >> 5] & (1 << (i & 31))) {
+ read_set[i >> 5] &= ~(1 << (i & 31));
+ fds[num_handles] = i;
+ handles[num_handles++] = (HANDLE) _get_osfhandle(i);
+ }
+ }
+
+ win_timeout = INFINITE;
+ if (timeout) win_timeout = (timeout[0] * 1000) + timeout[1];
+
+ /* Last parameter here is timeout in milliseconds. */
+ /* retval = WaitForMultipleObjects(num_handles, handles, 0, INFINITE); */
+ retval = WaitForMultipleObjects(num_handles, handles, 0, win_timeout);
+
+ if (retval < WAIT_ABANDONED) {
+ /* retval, at this point, is the index of the single live HANDLE/fd. */
+ read_set[fds[retval] >> 5] |= (1 << (fds[retval] & 31));
+ return 1;
+ }
+ return polling_write;
+}
+
+/*
+ * Windows doesn't have gettimeofday(), and we need it for the compiler,
+ * for serve-event, and for a couple other things. We don't need a timezone
+ * yet, however, and the closest we can easily get to a timeval is the
+ * seconds part. So that's what we do.
+ */
+int gettimeofday(long *timeval, long *timezone)
+{
+ timeval[0] = time(NULL);
+ timeval[1] = 0;
+
+ return 0;
+}
+#endif