discard revindex data when pack list changes

This is needed to fix verify-pack -v with multiple pack arguments.

Also, in theory, revindex data (if any) must be discarded whenever
reprepare_packed_git() is called. In practice this is hard to trigger
though.

Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-verify-pack.c

@@ -1,7 +1,7 @@
 #include "builtin.h"
 #include "cache.h"
 #include "pack.h"
-
+#include "pack-revindex.h"
 
 #define MAX_CHAIN 50
 
@@ -129,6 +129,7 @@ int cmd_verify_pack(int argc, const char **argv, const char *prefix)
 		else {
 			if (verify_one_pack(argv[1], verbose))
 				err = 1;
+			discard_revindex();
 			nothing_done = 0;
 		}
 		argc--; argv++;

pack-revindex.c

@@ -142,3 +142,15 @@ struct revindex_entry *find_pack_revindex(struct packed_git *p, off_t ofs)
 	} while (lo < hi);
 	die("internal error: pack revindex corrupt");
 }
+
+void discard_revindex(void)
+{
+	if (pack_revindex_hashsz) {
+		int i;
+		for (i = 0; i < pack_revindex_hashsz; i++)
+			if (pack_revindex[i].revindex)
+				free(pack_revindex[i].revindex);
+		free(pack_revindex);
+		pack_revindex_hashsz = 0;
+	}
+}

pack-revindex.h

@@ -7,5 +7,6 @@ struct revindex_entry {
 };
 
 struct revindex_entry *find_pack_revindex(struct packed_git *p, off_t ofs);
+void discard_revindex(void);
 
 #endif

sha1_file.c

@@ -990,6 +990,7 @@ void prepare_packed_git(void)
 
 void reprepare_packed_git(void)
 {
+	discard_revindex();
 	prepare_packed_git_run_once = 0;
 	prepare_packed_git();
 }

t/t5300-pack-object.sh

@@ -186,6 +186,12 @@ test_expect_success \
 			test-2-${packname_2}.idx \
 			test-3-${packname_3}.idx'
 
+test_expect_success \
+    'verify pack -v' \
+    'git verify-pack -v	test-1-${packname_1}.idx \
+			test-2-${packname_2}.idx \
+			test-3-${packname_3}.idx'
+
 test_expect_success \
     'verify-pack catches mismatched .idx and .pack files' \
     'cat test-1-${packname_1}.idx >test-3.idx &&