empdump: Omit redundant data from export, new -c includes it

Cuts size of export files in test suite by a factor of four.  Not a
big deal for disk usage, as export files compress very well, and disk
space is cheap anyway.  Export files are simply easier to work with
when they aren't full of redundant crap.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>

include/xdump.h

@@ -27,7 +27,7 @@
  *  xdump.h: Extended dumps
  *
  *  Known contributors to this file:
- *     Markus Armbruster, 2008-2013
+ *     Markus Armbruster, 2008-2014
  */
 
 #ifndef XDUMP_H
@@ -54,5 +54,6 @@ extern void xdcolhdr(struct xdstr *, struct castr[]);
 extern void xdflds(struct xdstr *, struct castr[], void *);
 extern void xdftr(struct xdstr *, int);
 extern int xundump(FILE *, char *, int *, int);
+extern int xundump_redundant(int, int, void *);
 
 #endif

man/empdump.6

@@ -4,7 +4,7 @@ empdump \- Export/import Empire game state
 .SH SYNOPSIS
 .B empdump
 [
-.B \-hmnvx
+.B \-chmnvx
 ]
 [
 .BI \-e " configfile"
@@ -18,6 +18,9 @@ empdump \- Export/import Empire game state
 exports and imports game state as plain text.
 .SH OPTIONS
 .TP
+.B \-c
+Use complete export format: don't omit data import doesn't need.
+.TP
 .BI \-e " configfile"
 Use game configuration in \fIconfigfile\fR.
 .TP

src/lib/common/xundump.c

@@ -135,6 +135,27 @@ can_fill_gaps(int type)
 	&& !have_hardcoded_indexes(type);
 }
 
+/*
+ * Is table TYPE's ID-th record OBJ redundant for xundump()
+ */
+int
+xundump_redundant(int type, int id, void *obj)
+{
+    char buf[EF_WITH_CADEF_MAX_ENTRY_SIZE];
+
+    if (!can_fill_gaps(type))
+	return 0;
+
+    if (may_truncate(type) && id == ef_nelem(type) - 1)
+	return 0;
+
+    ef_blank(type, id, buf);
+    if (ef_flags(type) & EFF_TYPED)
+	return ef_typedstr_eq((struct ef_typedstr *)buf,
+			      (struct ef_typedstr *)obj);
+    return !memcmp(obj, buf, empfile[type].size);
+}
+
 /*
  * Gripe about the current line to stderr, return -1.
  */

src/util/empdump.c

@@ -27,7 +27,7 @@
  *  empdump.c: Export/import Empire game state
  *
  *  Known contributors to this file:
- *     Markus Armbruster, 2008-2013
+ *     Markus Armbruster, 2008-2014
  */
 
 #include <config.h>
@@ -46,13 +46,14 @@
 
 static void exit_bad_arg(char *, ...)
     ATTRIBUTE((noreturn, format (printf, 1, 2)));
-static void dump_table(int, int, int);
+static void dump_table(int, int, int, int);
 
 int
 main(int argc, char *argv[])
 {
     char *config_file = NULL;
     char *import = NULL;
+    int complete = 0;
     int export = 0;
     int private = 0;
     int human = 1;
@@ -60,8 +61,11 @@ main(int argc, char *argv[])
     FILE *impf = NULL;
     int dirty[EF_MAX];
 
-    while ((opt = getopt(argc, argv, "e:i:mnxhv")) != EOF) {
+    while ((opt = getopt(argc, argv, "ce:i:mnxhv")) != EOF) {
 	switch (opt) {
+	case 'c':
+	    complete = 1;
+	    break;
 	case 'e':
 	    config_file = optarg;
 	    break;
@@ -79,6 +83,7 @@ main(int argc, char *argv[])
 	    break;
 	case 'h':
 	    printf("Usage: %s [OPTION]...\n"
+		   "  -c              use complete export format\n"
 		   "  -e CONFIG-FILE  configuration file\n"
 		   "                  (default %s)\n"
 		   "  -i DUMP-FILE    import from DUMP-FILE\n"
@@ -159,7 +164,7 @@ main(int argc, char *argv[])
 	for (i = 0; i < EF_MAX; i++) {
 	    if (!EF_IS_GAME_STATE(i))
 		continue;
-	    dump_table(i, human, !verified);
+	    dump_table(i, human, !verified, complete);
 	}
 	if (fclose(stdout) != 0) {
 	    fprintf(stderr, "%s: error writing export (%s)\n",
@@ -213,11 +218,11 @@ printf_wrapper(char *fmt, ...)
 }
 
 static void
-dump_table(int type, int human, int sloppy)
+dump_table(int type, int human, int sloppy, int complete)
 {
     struct xdstr xd;
     struct castr *ca;
-    int i;
+    int i, n;
     void *p;
 
     ca = ef_cadef(type);
@@ -227,9 +232,13 @@ dump_table(int type, int human, int sloppy)
     xdinit(&xd, NATID_BAD, human, sloppy, printf_wrapper);
     xdhdr(&xd, ef_nameof(type), 0);
     xdcolhdr(&xd, ca);
+    n = 0;
     for (i = 0; (p = ef_ptr(type, i)); i++) {
+	if (!complete && xundump_redundant(type, i, p))
+	    continue;
 	xdflds(&xd, ca, p);
+	n++;
 	printf("\n");
     }
-    xdftr(&xd, i);
+    xdftr(&xd, n);
 }