Custom timestamp filename added: ~/.faketimerc alternative

README

@@ -169,14 +169,15 @@ will be loaded, but just report the real system time. There are three
 ways to specify the faked time:
 
 a) By setting the environment variable FAKETIME.
-b) By using the file .faketimerc in your home directory.
-c) By using the file /etc/faketimerc for a system-wide default.
+b) By using the file given in the environment variable FAKETIME_TIMESTAMP_FILE
+c) By using the file .faketimerc in your home directory.
+d) By using the file /etc/faketimerc for a system-wide default.
 
-If you want to use b) or c), $HOME/.faketimerc or /etc/faketimerc consist of
+If you want to use b) c) or d), $HOME/.faketimerc or /etc/faketimerc consist of
 only one line of text with exactly the same content as the FAKETIME environment
 variable, which is described below. Note that /etc/faketimerc will only be used
-if there is no $HOME/.faketimerc, and the FAKETIME environment variable always
-has priority over the files.
+if there is no $HOME/.faketimerc nor FAKETIME_TIMESTAMP_FILE file exists, and
+the FAKETIME environment variable always has priority over the files.
 
 
 4b) Using absolute dates

src/libfaketime.c

@@ -1777,6 +1777,7 @@ int fake_clock_gettime(clockid_t clk_id, struct timespec *tp)
     if (parse_config_file)
     {
       static char user_faked_time[BUFFERLEN]; /* changed to static for caching in v0.6 */
+      char custom_filename[BUFSIZ];
       char filename[BUFSIZ];
       FILE *faketimerc;
       /* initialize with default or env. variable */
@@ -1794,8 +1795,10 @@ int fake_clock_gettime(clockid_t clk_id, struct timespec *tp)
        * a system-wide /etc/faketimerc present.
        * The /etc/faketimerc handling has been contributed by David Burley,
        * Jacob Moorman, and Wayne Davison of SourceForge, Inc. in version 0.6 */
+      (void) snprintf(custom_filename, BUFSIZ, "%s", getenv("FAKETIME_TIMESTAMP_FILE"));
       (void) snprintf(filename, BUFSIZ, "%s/.faketimerc", getenv("HOME"));
-      if ((faketimerc = fopen(filename, "rt")) != NULL ||
+      if ((faketimerc = fopen(custom_filename, "rt")) != NULL ||
+          (faketimerc = fopen(filename, "rt")) != NULL ||
           (faketimerc = fopen("/etc/faketimerc", "rt")) != NULL)
       {
         char line[BUFFERLEN];