Adding upstream version 8.32.upstream/8.32upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 344 insertions, 0 deletions

diff --git a/lib/tempname.c b/lib/tempname.c
new file mode 100644
index 0000000..5af79c5
--- /dev/null
+++ b/lib/tempname.c
@@ -0,0 +1,344 @@
+/* tempname.c - generate the name of a temporary file.
+
+   Copyright (C) 1991-2003, 2005-2007, 2009-2020 Free Software Foundation, Inc.
+
+   This program 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.
+
+   This program 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 <https://www.gnu.org/licenses/>.  */
+
+/* Extracted from glibc sysdeps/posix/tempname.c.  See also tmpdir.c.  */
+
+#if !_LIBC
+# include <config.h>
+# include "tempname.h"
+# include "randint.h"
+#endif
+
+#include <sys/types.h>
+#include <assert.h>
+
+#include <errno.h>
+#ifndef __set_errno
+# define __set_errno(Val) errno = (Val)
+#endif
+
+#include <stdio.h>
+#ifndef P_tmpdir
+# define P_tmpdir "/tmp"
+#endif
+#ifndef TMP_MAX
+# define TMP_MAX 238328
+#endif
+#ifndef __GT_FILE
+# define __GT_FILE      0
+# define __GT_DIR       1
+# define __GT_NOCREATE  2
+#endif
+#if !_LIBC && (GT_FILE != __GT_FILE || GT_DIR != __GT_DIR       \
+               || GT_NOCREATE != __GT_NOCREATE)
+# error report this to bug-gnulib@gnu.org
+#endif
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <fcntl.h>
+#include <sys/time.h>
+#include <stdint.h>
+#include <unistd.h>
+
+#include <sys/stat.h>
+
+#if _LIBC
+# define struct_stat64 struct stat64
+#else
+# define struct_stat64 struct stat
+# define __try_tempname try_tempname
+# define __gen_tempname gen_tempname
+# define __getpid getpid
+# define __gettimeofday gettimeofday
+# define __mkdir mkdir
+# define __open open
+# define __lxstat64(version, file, buf) lstat (file, buf)
+#endif
+
+#ifdef _LIBC
+# include <hp-timing.h>
+# if HP_TIMING_AVAIL
+#  define RANDOM_BITS(Var) \
+  if (__builtin_expect (value == UINT64_C (0), 0))                            \
+    {                                                                         \
+      /* If this is the first time this function is used initialize           \
+         the variable we accumulate the value in to some somewhat             \
+         random value.  If we'd not do this programs at startup time          \
+         might have a reduced set of possible names, at least on slow         \
+         machines.  */                                                        \
+      struct timeval tv;                                                      \
+      __gettimeofday (&tv, NULL);                                             \
+      value = ((uint64_t) tv.tv_usec << 16) ^ tv.tv_sec;                      \
+    }                                                                         \
+  HP_TIMING_NOW (Var)
+# endif
+#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
+
+#if _LIBC
+/* Return nonzero if DIR is an existent directory.  */
+static int
+direxists (const char *dir)
+{
+  struct_stat64 buf;
+  return __xstat64 (_STAT_VER, dir, &buf) == 0 && S_ISDIR (buf.st_mode);
+}
+
+/* Path search algorithm, for tmpnam, tmpfile, etc.  If DIR is
+   non-null and exists, uses it; otherwise uses the first of $TMPDIR,
+   P_tmpdir, /tmp that exists.  Copies into TMPL a template suitable
+   for use with mk[s]temp.  Will fail (-1) if DIR is non-null and
+   doesn't exist, none of the searched dirs exists, or there's not
+   enough space in TMPL. */
+int
+__path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
+               int try_tmpdir)
+{
+  const char *d;
+  size_t dlen, plen;
+
+  if (!pfx || !pfx[0])
+    {
+      pfx = "file";
+      plen = 4;
+    }
+  else
+    {
+      plen = strlen (pfx);
+      if (plen > 5)
+        plen = 5;
+    }
+
+  if (try_tmpdir)
+    {
+      d = __secure_getenv ("TMPDIR");
+      if (d != NULL && direxists (d))
+        dir = d;
+      else if (dir != NULL && direxists (dir))
+        /* nothing */ ;
+      else
+        dir = NULL;
+    }
+  if (dir == NULL)
+    {
+      if (direxists (P_tmpdir))
+        dir = P_tmpdir;
+      else if (strcmp (P_tmpdir, "/tmp") != 0 && direxists ("/tmp"))
+        dir = "/tmp";
+      else
+        {
+          __set_errno (ENOENT);
+          return -1;
+        }
+    }
+
+  dlen = strlen (dir);
+  while (dlen > 1 && dir[dlen - 1] == '/')
+    dlen--;                     /* remove trailing slashes */
+
+  /* check we have room for "${dir}/${pfx}XXXXXX\0" */
+  if (tmpl_len < dlen + 1 + plen + 6 + 1)
+    {
+      __set_errno (EINVAL);
+      return -1;
+    }
+
+  sprintf (tmpl, "%.*s/%.*sXXXXXX", (int) dlen, dir, (int) plen, pfx);
+  return 0;
+}
+#endif /* _LIBC */
+
+static inline bool _GL_ATTRIBUTE_PURE
+check_x_suffix (char const *s, size_t len)
+{
+  return len <= strspn (s, "X");
+}
+
+/* These are the characters used in temporary file names.  */
+static const char letters[] =
+"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+
+int
+try_tempname_len (char *tmpl, int suffixlen, void *args,
+                  int (*tryfunc) (char *, void *), size_t x_suffix_len)
+{
+  size_t len;
+  char *XXXXXX;
+  unsigned int count;
+  int fd = -1;
+  int save_errno = errno;
+  struct randint_source *rand_src;
+
+  /* A lower bound on the number of temporary files to attempt to
+     generate.  The maximum total number of temporary file names that
+     can exist for a given template is 62**6.  It should never be
+     necessary to try all of these combinations.  Instead if a reasonable
+     number of names is tried (we define reasonable as 62**3) fail to
+     give the system administrator the chance to remove the problems.
+     This value requires that X_SUFFIX_LEN be at least 3.  */
+#define ATTEMPTS_MIN (62 * 62 * 62)
+
+  /* The number of times to attempt to generate a temporary file.  To
+     conform to POSIX, this must be no smaller than TMP_MAX.  */
+#if ATTEMPTS_MIN < TMP_MAX
+  unsigned int attempts = TMP_MAX;
+#else
+  unsigned int attempts = ATTEMPTS_MIN;
+#endif
+
+  len = strlen (tmpl);
+  if (len < x_suffix_len + suffixlen
+      || ! check_x_suffix (&tmpl[len - x_suffix_len - suffixlen],
+                           x_suffix_len))
+    {
+      __set_errno (EINVAL);
+      return -1;
+    }
+
+  /* This is where the Xs start.  */
+  XXXXXX = &tmpl[len - x_suffix_len - suffixlen];
+
+  /* Get some more or less random data.  */
+  rand_src = randint_all_new (NULL, x_suffix_len);
+  if (! rand_src)
+    return -1;
+
+  for (count = 0; count < attempts; ++count)
+    {
+      size_t i;
+
+      for (i = 0; i < x_suffix_len; i++)
+        XXXXXX[i] = letters[randint_genmax (rand_src, sizeof letters - 2)];
+
+      fd = tryfunc (tmpl, args);
+      if (fd >= 0)
+        {
+          __set_errno (save_errno);
+          goto done;
+        }
+      else if (errno != EEXIST)
+        {
+          fd = -1;
+          goto done;
+        }
+    }
+
+  randint_all_free (rand_src);
+
+  /* We got out of the loop because we ran out of combinations to try.  */
+  __set_errno (EEXIST);
+  return -1;
+
+ done:
+  {
+    int saved_errno = errno;
+    randint_all_free (rand_src);
+    __set_errno (saved_errno);
+  }
+  return fd;
+}
+
+static int
+try_file (char *tmpl, void *flags)
+{
+  int *openflags = flags;
+  return __open (tmpl,
+                 (*openflags & ~O_ACCMODE)
+                 | O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
+}
+
+static int
+try_dir (char *tmpl, void *flags _GL_UNUSED)
+{
+  return __mkdir (tmpl, S_IRUSR | S_IWUSR | S_IXUSR);
+}
+
+static int
+try_nocreate (char *tmpl, void *flags _GL_UNUSED)
+{
+  struct_stat64 st;
+
+  if (__lxstat64 (_STAT_VER, tmpl, &st) == 0 || errno == EOVERFLOW)
+    __set_errno (EEXIST);
+  return errno == ENOENT ? 0 : -1;
+}
+
+/* Generate a temporary file name based on TMPL.  TMPL must match the
+   rules for mk[s]temp (i.e., end in at least X_SUFFIX_LEN "X"s,
+   possibly with a suffix).
+   The name constructed does not exist at the time of the call to
+   this function.  TMPL is overwritten with the result.
+
+   KIND may be one of:
+   __GT_NOCREATE:       simply verify that the name does not exist
+                        at the time of the call.
+   __GT_FILE:           create the file using open(O_CREAT|O_EXCL)
+                        and return a read-write fd.  The file is mode 0600.
+   __GT_DIR:            create a directory, which will be mode 0700.
+
+   We use a clever algorithm to get hard-to-predict names. */
+int
+gen_tempname_len (char *tmpl, int suffixlen, int flags, int kind,
+                  size_t x_suffix_len)
+{
+  int (*tryfunc) (char *, void *);
+
+  switch (kind)
+    {
+    case __GT_FILE:
+      tryfunc = try_file;
+      break;
+
+    case __GT_DIR:
+      tryfunc = try_dir;
+      break;
+
+    case __GT_NOCREATE:
+      tryfunc = try_nocreate;
+      break;
+
+    default:
+      assert (! "invalid KIND in __gen_tempname");
+      abort ();
+    }
+  return try_tempname_len (tmpl, suffixlen, &flags, tryfunc, x_suffix_len);
+}
+
+int
+__gen_tempname (char *tmpl, int suffixlen, int flags, int kind)
+{
+  return gen_tempname_len (tmpl, suffixlen, flags, kind, 6);
+}
+
+int
+__try_tempname (char *tmpl, int suffixlen, void *args,
+                int (*tryfunc) (char *, void *))
+{
+  return try_tempname_len (tmpl, suffixlen, args, tryfunc, 6);
+}