1 files changed, 117 insertions, 0 deletions
diff --git a/src/libs/libgroff/tmpname.cpp b/src/libs/libgroff/tmpname.cpp
new file mode 100644
index 0000000..69dc9a4
--- /dev/null
+++ b/src/libs/libgroff/tmpname.cpp
@@ -0,0 +1,117 @@
+/* Copyright (C) 2001-2020 Free Software Foundation, Inc.
+     Written by Werner Lemberg (wl@gnu.org)
+
+This file is part of groff.
+
+groff is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+groff 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 General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>. */
+
+
+/* This file is heavily based on the function __gen_tempname() in the
+   file tempname.c which is part of the fileutils package. */
+
+
+#include "lib.h"
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <time.h>
+
+#include "posix.h"
+#include "nonposix.h"
+
+#ifndef TMP_MAX
+# define TMP_MAX 238328
+#endif
+
+#if HAVE_SYS_TIME_H
+# include <sys/time.h>
+#endif
+
+#ifdef HAVE_GETTIMEOFDAY
+#ifdef NEED_DECLARATION_GETTIMEOFDAY
+extern "C" {
+  int gettimeofday(struct timeval *, void *);
+}
+#endif
+#endif
+
+#if HAVE_CC_INTTYPES_H
+# include <inttypes.h>
+#endif
+
+/* Use the widest available unsigned type if uint64_t is not
+   available.  The algorithm below extracts a number less than 62**6
+   (approximately 2**35.725) from uint64_t, so ancient hosts where
+   uintmax_t is only 32 bits lose about 3.725 bits of randomness,
+   which is better than not having mkstemp at all.  */
+#if !defined UINT64_MAX && !defined uint64_t
+# define uint64_t uintmax_t
+#endif
+
+/* These are the characters used in temporary filenames.  */
+static const char letters[] =
+"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+
+int gen_tempname(char *tmpl, int dir)
+{
+  static uint64_t value;
+
+  size_t len = strlen(tmpl);
+  if (len < 6 || strcmp(&tmpl[len - 6], "XXXXXX"))
+    return -1; /* EINVAL */
+
+  /* This is where the Xs start.  */
+  char *XXXXXX = &tmpl[len - 6];
+
+  /* Get some more or less random data.  */
+#if HAVE_GETTIMEOFDAY
+  timeval tv;
+  gettimeofday(&tv, 0);
+  uint64_t random_time_bits = ((uint64_t)tv.tv_usec << 16) ^ tv.tv_sec;
+#else
+  uint64_t random_time_bits = time(0);
+#endif
+  value += random_time_bits ^ getpid();
+
+  for (int count = 0; count < TMP_MAX; value += 7777, ++count) {
+    uint64_t v = value;
+
+    /* Fill in the random bits.  */
+    XXXXXX[0] = letters[v % 62];
+    v /= 62;
+    XXXXXX[1] = letters[v % 62];
+    v /= 62;
+    XXXXXX[2] = letters[v % 62];
+    v /= 62;
+    XXXXXX[3] = letters[v % 62];
+    v /= 62;
+    XXXXXX[4] = letters[v % 62];
+    v /= 62;
+    XXXXXX[5] = letters[v % 62];
+
+    int fd = dir ? mkdir(tmpl, S_IRUSR | S_IWUSR | S_IXUSR)
+		 : open(tmpl,
+			O_RDWR | O_CREAT | O_EXCL | O_BINARY,
+			S_IRUSR | S_IWUSR);
+
+    if (fd >= 0)
+      return fd;
+    else if (errno != EEXIST)
+      return -1;
+  }
+
+  /* We got out of the loop because we ran out of combinations to try.  */
+  return -1; /* EEXIST */
+}