/* Copyright (C) 1996-2019 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #include <errno.h> #include <libc-lock.h> #include <shadow.h> #include <stdlib.h> /* A reasonable size for a buffer to start with. */ #define BUFLEN_SPWD 1024 /* We need to protect the dynamic buffer handling. */ __libc_lock_define_initialized (static, lock); /* Read one shadow entry from the given stream. */ struct spwd * sgetspent (const char *string) { static char *buffer; static size_t buffer_size; static struct spwd resbuf; struct spwd *result; int save; /* Get lock. */ __libc_lock_lock (lock); /* Allocate buffer if not yet available. */ if (buffer == NULL) { buffer_size = BUFLEN_SPWD; buffer = malloc (buffer_size); } while (buffer != NULL && (__sgetspent_r (string, &resbuf, buffer, buffer_size, &result) == ERANGE)) { char *new_buf; buffer_size += BUFLEN_SPWD; new_buf = realloc (buffer, buffer_size); if (new_buf == NULL) { /* We are out of memory. Free the current buffer so that the process gets a chance for a normal termination. */ save = errno; free (buffer); __set_errno (save); } buffer = new_buf; } if (buffer == NULL) result = NULL; /* Release lock. Preserve error value. */ save = errno; __libc_lock_unlock (lock); __set_errno (save); return result; }