mkdir exportdir's parent, if necessary

Tux Paint's export features will fail if the parent
of the export directory didn't exist.  e.g., using the
default (either via XDG or hard-coded fallback) of
"~/Pictures/TuxPaint/", Tux Paint could not export if
"~/Pictures/" didn't exist yet.  It will now try to
mkdir it as well.  h/t Tim Dickson

Updated OPTIONS documents to explain this.

Also, documenting --exportdir in manpage (was missing!)

docs/CHANGES.txt

@@ -8,7 +8,7 @@ http://www.tuxpaint.org/
 
 $Id$
 
-2021.January.10 (0.9.26)
+2021.January.13 (0.9.26)
   * New Magic Tools:
     ----------------
     * Pixels
@@ -27,6 +27,15 @@ $Id$
     * Documented how to build Tux Paint using old macOS
       Mark K. Kim <markuskimius@gmail.com>
 
+  * Other Improvements
+    ------------------
+    * If parent of export directory doesn't exist, Tux Paint will
+      try to create it as well.
+      (Only one level up; e.g., with an export location like
+      /path/to/Pictures/TuxPaint/, it will try to create
+      /path/to/Pictures/ if it doesn't exist, but not its parents).
+      h/t Tim Dickson
+
 2020.December.27 (0.9.25)
   * New Features
     ------------

docs/en/OPTIONS.txt

@@ -3,7 +3,7 @@
 
 Options Documentation
 
-        Copyright (c) 2002-2020 by various contributors; see AUTHORS.txt
+        Copyright (c) 2002-2021 by various contributors; see AUTHORS.txt
                             http://www.tuxpaint.org/
 
                                December 27, 2020
@@ -607,9 +607,14 @@ Windows Users
              Note: When the defaults are used, a new "TuxPaint" subdirectory
              will be created and used. (e.g., "~/Pictures/TuxPaint") When the
              "--exportdir" option is used, the exact path specified will be
-             used (no "TuxPaint" subdirectory is created). It is expected
+             used (no "TuxPaint" subdirectory is created).
-             that the parent directory exists. (The directory itself will be
+
-             created, if it doesn't.)
+             The directory itself (e.g., "~/Pictures/TuxPaint") will be
+             created, if it doesn't exist.
+
+             If the parent directory (e.g., "~/Pictures") also does not
+             exist, Tux Paint will attempt to create it as well (but not any
+             directories higher than that).
 
              Example: exportdir=/home/penguin/TuxPaintExports
 

docs/en/README.txt

@@ -6,7 +6,7 @@
           Copyright 2002-2021 by various contributors; see AUTHORS.txt
                             http://www.tuxpaint.org/
 
-                        June 14, 2002 - January 6, 2021
+                        June 14, 2002 - January 13, 2021
 
      ----------------------------------------------------------------------
 

docs/en/html/OPTIONS.html

@@ -25,7 +25,7 @@
       </h2>
 
       <p>
-        Copyright (c) 2002-2020 by various contributors; see
+        Copyright (c) 2002-2021 by various contributors; see
         AUTHORS.txt<br>
         <a href=
         "http://www.tuxpaint.org/">http://www.tuxpaint.org/</a>
@@ -1274,9 +1274,16 @@
             and used. (e.g., "<code>~/Pictures/TuxPaint</code>")
             When the "<code>--exportdir</code>" option is used, the
             exact path specified will be used (no
-            "<code>TuxPaint</code>" subdirectory is created). It is
+            "<code>TuxPaint</code>" subdirectory is created).
-            expected that the parent directory exists. (The
+          </p>
-            directory itself will be created, if it doesn't.)
+          <p>
+            The directory itself (e.g., "<code>~/Pictures/TuxPaint</code>")
+            will be created, if it doesn't exist.
+          </p>
+          <p>
+            If the <em>parent</em> directory (e.g., "<code>~/Pictures</code>")
+            also does not exist, Tux&nbsp;Paint will attempt to create it
+            as well (but not any directories higher than that).
           </p>
 
           <p>

docs/en/html/README.html

@@ -35,7 +35,7 @@
       </p>
 
       <p>
-        June 14, 2002 - January 6, 2021
+        June 14, 2002 - January 13, 2021
       </p>
     </center>
 

src/get_fname.c

@@ -1,7 +1,7 @@
 /*
   get_fname.c
 
-  Copyright (c) 2009 - 2020
+  Copyright (c) 2009 - 2021
   http://www.tuxpaint.org/
 
   This program is free software; you can redistribute it and/or modify
@@ -57,6 +57,11 @@
     and easily-accessible place for end users to retrieve the exports.
 
     The defaults may be overridden with the "--exportdir" option.
+
+  * DIR_EXPORT_PARENT: The parent of the directory
+    specified by DIR_EXPORT.  (e.g., if /home/username/Pictures/TuxPaint/
+    is our export dir., we may need to make .../Pictures first,
+    the first time we export something.)
 */
 
 
@@ -88,7 +93,7 @@ char *get_fname(const char *const name, int kind)
     dir = savedir;
   } else if (kind == DIR_DATA) {
     dir = datadir;
-  } else if (kind == DIR_EXPORT) {
+  } else if (kind == DIR_EXPORT || kind == DIR_EXPORT_PARENT) {
     dir = exportdir;
   }
 
@@ -97,6 +102,20 @@ char *get_fname(const char *const name, int kind)
 	   dir, (*name) ? '/' : '\0', /* Some mkdir()'s don't like trailing slashes */
 	   name);
 
+  if (kind == DIR_EXPORT_PARENT) {
+    int len, i, stop;
+
+    stop = -1;
+    len = strlen(f);
+    for (i = len - 1; i >= 0 && stop == -1; i--) {
+      if (f[i] == '/')
+        stop = i;
+    }
+    if (stop != -1) {
+      f[stop] = '\0';
+    }
+  }
+
   return strdup(f);
 }
 

src/get_fname.h

@@ -1,7 +1,7 @@
 /*
   get_fname.h
 
-  Copyright (c) 2009 - July 25, 2020
+  Copyright (c) 2009 - January 13, 2021
   http://www.tuxpaint.org/
 
   This program is free software; you can redistribute it and/or modify
@@ -34,7 +34,8 @@ enum
   /* (See get_fname.c for details) */
   DIR_SAVE,
   DIR_DATA,
-  DIR_EXPORT
+  DIR_EXPORT,
+  DIR_EXPORT_PARENT
 };
 
 char *get_fname(const char *const name, int kind);

src/manpage/tuxpaint.1

@@ -1,5 +1,5 @@
-.\" tuxpaint.1 - 2020.12.27
+.\" tuxpaint.1 - 2021.01.13
-.TH TUXPAINT 1 "27 December 2020" "0.9.26" "Tux Paint"
+.TH TUXPAINT 1 "13 January 2021" "0.9.26" "Tux Paint"
 .SH NAME
 tuxpaint -- "Tux Paint", a drawing program for young children.
 
@@ -131,6 +131,8 @@ tuxpaint -- "Tux Paint", a drawing program for young children.
 .br
 [\-\-savedir \fIDIR\fP]
 .br
+[\-\-exportdir \fIDIR\fP]
+.br
 [\-\-datadir \fIDIR\fP]
 .br
 [\-\-saveover]
@@ -484,7 +486,11 @@ Use the \fIalllocalefonts\fP option to load all such fonts, for use in the
 
 .TP 8
 .B \-\-savedir \fIDIR\fP
-Specify where \fITux Paint\fP should save files.
+Specify where \fITux Paint\fP should save and load its drawings.
+
+.TP 8
+.B \-\-exportdir \fIDIR\fP
+Specify where \fITux Paint\fP should export drawings and animations.
 
 .TP 8
 .B \-\-datadir \fIDIR\fP

src/tuxpaint.c

@@ -25963,9 +25963,16 @@ static char * get_export_filepath(const char * ext) {
 
 
   /* Make sure the export dir exists */
-  if (!make_directory(DIR_EXPORT, "", "Can't create export directory (E016)"))
+  if (!make_directory(DIR_EXPORT, "", "Can't create export directory; will try to make its parent (E016)"))
     {
-      return NULL;
+      /* See if perhaps we need to try and make its parent directory first? */
+      if (make_directory(DIR_EXPORT_PARENT, "", "Can't create export directory parent (E016b)")) {
+        if (!make_directory(DIR_EXPORT, "", "Can't create export directory (E016c)")) {
+          return NULL;
+        }
+      } else {
+        return NULL;
+      }
     }
 
   /* Create a unique filename, within that dir */