Create an open_tmpfd() function to return temp files by FD. Use it.

1 files changed, 79 insertions, 0 deletions

diff --git a/misc.c b/misc.c
index df208a6..800e857 100644
--- a/misc.c
+++ b/misc.c
@@ -930,6 +930,85 @@ get_path_max (void)
 #endif
 
 
+/* Provide support for temporary files.  */
+
+#ifndef HAVE_STDLIB_H
+# ifdef HAVE_MKSTEMP
+int mkstemp (char *template);
+# else
+char *mktemp (char *template);
+# endif
+#endif
+
+/* This is only used by output-sync, and it may not be portable to Windows.  */
+#ifdef OUTPUT_SYNC
+
+/* Returns a file descriptor to a temporary file.  The file is automatically
+   closed/deleted on exit.  Don't use a FILE* stream.  */
+int
+open_tmpfd()
+{
+  int fd = -1;
+  FILE *tfile = tmpfile();
+
+  if (! tfile)
+    pfatal_with_name ("tmpfile");
+
+  /* Create a duplicate so we can close the stream.  */
+  fd = dup (fileno (tfile));
+  if (fd < 0)
+    pfatal_with_name ("dup");
+
+  fclose (tfile);
+
+  return fd;
+}
+
+#endif
+
+FILE *
+open_tmpfile(char **name, const char *template)
+{
+#ifdef HAVE_FDOPEN
+  int fd;
+#endif
+
+#if defined HAVE_MKSTEMP || defined HAVE_MKTEMP
+# define TEMPLATE_LEN   strlen (template)
+#else
+# define TEMPLATE_LEN   L_tmpnam
+#endif
+  *name = xmalloc (TEMPLATE_LEN + 1);
+  strcpy (*name, template);
+
+#if defined HAVE_MKSTEMP && defined HAVE_FDOPEN
+  /* It's safest to use mkstemp(), if we can.  */
+  fd = mkstemp (*name);
+  if (fd == -1)
+    return 0;
+  return fdopen (fd, "w");
+#else
+# ifdef HAVE_MKTEMP
+  (void) mktemp (*name);
+# else
+  (void) tmpnam (*name);
+# endif
+
+# ifdef HAVE_FDOPEN
+  /* Can't use mkstemp(), but guard against a race condition.  */
+  fd = open (*name, O_CREAT|O_EXCL|O_WRONLY, 0600);
+  if (fd == -1)
+    return 0;
+  return fdopen (fd, "w");
+# else
+  /* Not secure, but what can we do?  */
+  return fopen (*name, "w");
+# endif
+#endif
+}
+
+
+
 /* This code is stolen from gnulib.
    If/when we abandon the requirement to work with K&R compilers, we can
    remove this (and perhaps other parts of GNU make!) and migrate to using