add support for running the tests in parallel

By isolating each test temporary directory.

prog/reg_wrapper.sh

@@ -60,4 +60,6 @@ if [ -z "${srcdir}" ]; then
   srcdir="${0%/*}"
 fi
 
+export LEPT_TMPDIR="${PWD}/${TEST_NAME}.tmp"
+
 exec "$@" /bin/sh -c 'cd "$1" && "$2" generate && "$2" compare' -- "${srcdir}" "${PWD}/${TEST}"

src/utils2.c

@@ -3077,7 +3077,7 @@ genPathname(const char  *dir,
 {
 l_int32  is_macos = FALSE;
 l_int32  is_win32 = FALSE;
-char    *cdir, *pathout;
+char    *cdir, *pathout, *tmpdir;
 l_int32  dirlen, namelen;
 size_t   size;
 
@@ -3109,6 +3109,7 @@ size_t   size;
         return (char *)ERROR_PTR("pathout not made", __func__, NULL);
     }
 
+    tmpdir = getenv("LEPT_TMPDIR");
 #ifdef __APPLE__
     is_macos = TRUE;
 #endif  /* __APPLE__ */
@@ -3120,10 +3121,15 @@ size_t   size;
          * There is no path rewriting on unix, and on win32, we do not
          * rewrite unless the specified directory is /tmp or
          * a subdirectory of /tmp */
-    if ((!is_macos && !is_win32) || dirlen < 4 ||
+    if ((!is_macos && !is_win32 && tmpdir == NULL) || dirlen < 4 ||
         (dirlen == 4 && strncmp(cdir, "/tmp", 4) != 0) ||  /* not in "/tmp" */
         (dirlen > 4 && strncmp(cdir, "/tmp/", 5) != 0)) {  /* not in "/tmp/" */
         stringCopy(pathout, cdir, dirlen);
+    } else if (tmpdir != NULL) {
+        stringCopy(pathout, tmpdir, strlen(tmpdir));
+            /* Add the rest of cdir */
+        if (dirlen > 4)
+            stringCat(pathout, size, cdir + 4);
     } else if (is_macos) {  /* Rewrite for macOS with "/tmp" specified for the directory. */
 #ifdef __APPLE__
         char tmpdir[PATH_MAX];