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-rw-r--r--w32/compat/posixfcn.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/w32/compat/posixfcn.c b/w32/compat/posixfcn.c
index cde81ce..0ebf9a6 100644
--- a/w32/compat/posixfcn.c
+++ b/w32/compat/posixfcn.c
@@ -257,6 +257,106 @@ same_stream (FILE *f1, FILE *f2)
return 0;
}
+/* A replacement for tmpfile, since the MSVCRT implementation creates
+ the file in the root directory of the current drive, which might
+ not be writable by our user. Most of the code borrowed from
+ create_batch_file, see job.c. */
+FILE *
+tmpfile (void)
+{
+ char temp_path[MAXPATHLEN];
+ unsigned path_size = GetTempPath (sizeof temp_path, temp_path);
+ int path_is_dot = 0;
+ /* The following variable is static so we won't try to reuse a name
+ that was generated a little while ago, because that file might
+ not be on disk yet, since we use FILE_ATTRIBUTE_TEMPORARY below,
+ which tells the OS it doesn't need to flush the cache to disk.
+ If the file is not yet on disk, we might think the name is
+ available, while it really isn't. This happens in parallel
+ builds, where Make doesn't wait for one job to finish before it
+ launches the next one. */
+ static unsigned uniq = 0;
+ static int second_loop = 0;
+ const char base[] = "gmake_tmpf";
+ const unsigned sizemax = sizeof base - 1 + 4 + 10 + 10;
+ unsigned pid = GetCurrentProcessId ();
+
+ if (path_size == 0)
+ {
+ path_size = GetCurrentDirectory (sizeof temp_path, temp_path);
+ path_is_dot = 1;
+ }
+
+ ++uniq;
+ if (uniq >= 0x10000 && !second_loop)
+ {
+ /* If we already had 64K batch files in this
+ process, make a second loop through the numbers,
+ looking for free slots, i.e. files that were
+ deleted in the meantime. */
+ second_loop = 1;
+ uniq = 1;
+ }
+ while (path_size > 0 &&
+ path_size + sizemax < sizeof temp_path &&
+ !(uniq >= 0x10000 && second_loop))
+ {
+ sprintf (temp_path + path_size,
+ "%s%s%u-%x.tmp",
+ temp_path[path_size - 1] == '\\' ? "" : "\\",
+ base, pid, uniq);
+ HANDLE h = CreateFile (temp_path, /* file name */
+ GENERIC_READ | GENERIC_WRITE | DELETE, /* desired access */
+ FILE_SHARE_READ | FILE_SHARE_WRITE, /* share mode */
+ NULL, /* default security attributes */
+ CREATE_NEW, /* creation disposition */
+ FILE_ATTRIBUTE_NORMAL | /* flags and attributes */
+ FILE_ATTRIBUTE_TEMPORARY |
+ FILE_FLAG_DELETE_ON_CLOSE,
+ NULL); /* no template file */
+
+ if (h == INVALID_HANDLE_VALUE)
+ {
+ const DWORD er = GetLastError ();
+
+ if (er == ERROR_FILE_EXISTS || er == ERROR_ALREADY_EXISTS)
+ {
+ ++uniq;
+ if (uniq == 0x10000 && !second_loop)
+ {
+ second_loop = 1;
+ uniq = 1;
+ }
+ }
+
+ /* The temporary path is not guaranteed to exist, or might
+ not be writable by user. Use the current directory as
+ fallback. */
+ else if (path_is_dot == 0)
+ {
+ path_size = GetCurrentDirectory (sizeof temp_path, temp_path);
+ path_is_dot = 1;
+ }
+
+ else
+ {
+ errno = EACCES;
+ break;
+ }
+ }
+ else
+ {
+ int fd = _open_osfhandle ((intptr_t)h, 0);
+
+ return _fdopen (fd, "w+b");
+ }
+ }
+
+ if (uniq >= 0x10000)
+ errno = EEXIST;
+ return NULL;
+}
+
#endif /* !NO_OUTPUT_SYNC */
#if MAKE_LOAD