From 7d105f87fc66a37e2d859fee600543e592caa881 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Mon, 23 Aug 2010 15:26:49 +0000
Subject: [PATCH] Update the "showdb" debug utility to handle 64K page database
 and with extra options to decode the freelist structure.

FossilOrigin-Name: 1070918e3b68c0ba5bfab11a97214b87c601f93c
---
 manifest      | 18 ++++++-------
 manifest.uuid |  2 +-
 tool/showdb.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++--
 3 files changed, 83 insertions(+), 12 deletions(-)

diff --git a/manifest b/manifest
index 25d786d2ff..59005ebd85 100644
--- a/manifest
+++ b/manifest
@@ -1,8 +1,8 @@
 -----BEGIN PGP SIGNED MESSAGE-----
 Hash: SHA1
 
-C Version\s3.7.1\srelease\scandidate
-D 2010-08-21T16:01:46
+C Update\sthe\s"showdb"\sdebug\sutility\sto\shandle\s64K\spage\sdatabase\sand\swith\nextra\soptions\sto\sdecode\sthe\sfreelist\sstructure.
+D 2010-08-23T15:26:50
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 543f91f24cd7fee774ecc0a61c19704c0c3e78fd
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -836,7 +836,7 @@ F tool/shell2.test 5dc76b8005b465f420fed8241621da7513060ff3
 F tool/shell3.test 4fad469e8003938426355afdf34155f08c587836
 F tool/shell4.test 35f9c3d452b4e76d5013c63e1fd07478a62f14ce
 F tool/shell5.test 62bfaf9267296da1b91e4b1c03e44e7b393f6a94
-F tool/showdb.c 01c20e8181941b714fe07f72c64a7560fee17ff9
+F tool/showdb.c c7a978cf525ef0f8bc2fd29cd52108dd1dfa605a
 F tool/showjournal.c ec3b171be148656827c4949fbfb8ab4370822f87
 F tool/showwal.c f09e5a80a293919290ec85a6a37c85a5ddcf37d9
 F tool/soak1.tcl 8d407956e1a45b485a8e072470a3e629a27037fe
@@ -848,14 +848,14 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P 44de3cab9c89eb28485c0dc36d791b1c61d56b34
-R ba75d512677d6cf0802a70f734aafd6f
+P 3613b0695a5e990905ab146fadcab34dd04d5874
+R 058fa6e3ab648ae5ff66e22c57c21a88
 U drh
-Z 9eb9cc7f3392e65cec0523ad38099f7c
+Z 4b496641e3aad55cb1970e3775c32e6e
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.6 (GNU/Linux)
 
-iD8DBQFMb/huoxKgR168RlERAp5nAJ9bQ/OZp/nGB/mbch5eawtJ3xzNqQCdH2LV
-awMpPL8qm3hJm5LCIu8Eivk=
-=ZYFd
+iD8DBQFMcpM9oxKgR168RlERAiQ4AKCNTq26d6guoArVL/8XVQDv9ujn6gCbB8sK
+0u6T4zf+ph77zjra1ytd08E=
+=CUDO
 -----END PGP SIGNATURE-----
diff --git a/manifest.uuid b/manifest.uuid
index 761b671e6c..1be9cbc9ad 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-3613b0695a5e990905ab146fadcab34dd04d5874
\ No newline at end of file
+1070918e3b68c0ba5bfab11a97214b87c601f93c
\ No newline at end of file
diff --git a/tool/showdb.c b/tool/showdb.c
index a54eea8a96..f313b1aff9 100644
--- a/tool/showdb.c
+++ b/tool/showdb.c
@@ -35,6 +35,13 @@ static int decodeVarint(const unsigned char *z, i64 *pVal){
   return 9;
 }
 
+/*
+** Extract a big-endian 32-bit integer
+*/
+static unsigned int decodeInt32(const unsigned char *z){
+  return (z[0]<<24) + (z[1]<<16) + (z[2]<<8) + z[3];
+}
+
 /* Report an out-of-memory error and die.
 */
 static void out_of_memory(void){
@@ -246,11 +253,64 @@ static void decode_btree_page(unsigned char *a, int pgno, int hdrSize){
   }
 }
 
+/*
+** Decode a freelist trunk page.
+*/
+static void decode_trunk_page(
+  int pgno,             /* The page number */
+  int pagesize,         /* Size of each page */
+  int detail,           /* Show leaf pages if true */
+  int recursive         /* Follow the trunk change if true */
+){
+  int n, i, k;
+  unsigned char *a;
+  while( pgno>0 ){
+    a = getContent((pgno-1)*pagesize, pagesize);
+    printf("Decode of freelist trunk page %d:\n", pgno);
+    print_decode_line(a, 0, 4, "Next freelist trunk page");
+    print_decode_line(a, 4, 4, "Number of entries on this page");
+    if( detail ){
+      n = (int)decodeInt32(&a[4]);
+      for(i=0; i<n; i++){
+        unsigned int x = decodeInt32(&a[8+4*i]);
+        char zIdx[10];
+        sprintf(zIdx, "[%d]", i);
+        printf("  %5s %7u", zIdx, x);
+        if( i%5==4 ) printf("\n");
+      }
+      if( i%5!=0 ) printf("\n");
+    }
+    if( !recursive ){
+      pgno = 0;
+    }else{
+      pgno = (int)decodeInt32(&a[0]);
+    }
+    free(a);
+  }
+}
+
+/*
+** Print a usage comment
+*/
+static void usage(const char *argv0){
+  fprintf(stderr, "Usage %s FILENAME ?args...?\n\n", argv0);
+  fprintf(stderr,
+    "args:\n"
+    "    dbheader        Show database header\n"
+    "    NNN..MMM        Show hex of pages NNN through MMM\n"
+    "    NNN..end        Show hex of pages NNN through end of file\n"
+    "    NNNb            Decode btree page NNN\n"
+    "    NNNt            Decode freelist trunk page NNN\n"
+    "    NNNtd           Show leave freelist pages on the decode\n"
+    "    NNNtr           Recurisvely decode freelist starting at NNN\n"
+  );
+}
+
 int main(int argc, char **argv){
   struct stat sbuf;
   unsigned char zPgSz[2];
   if( argc<2 ){
-    fprintf(stderr,"Usage: %s FILENAME ?PAGE? ...\n", argv[0]);
+    usage(argv[0]);
     exit(1);
   }
   db = open(argv[1], O_RDONLY);
@@ -262,7 +322,7 @@ int main(int argc, char **argv){
   zPgSz[1] = 0;
   lseek(db, 16, SEEK_SET);
   read(db, zPgSz, 2);
-  pagesize = zPgSz[0]*256 + zPgSz[1];
+  pagesize = zPgSz[0]*256 + zPgSz[1]*65536;
   if( pagesize==0 ) pagesize = 1024;
   printf("Pagesize: %d\n", pagesize);
   fstat(db, &sbuf);
@@ -304,6 +364,17 @@ int main(int argc, char **argv){
         decode_btree_page(a, iStart, hdrSize);
         free(a);
         continue;
+      }else if( zLeft && zLeft[0]=='t' ){
+        unsigned char *a;
+        int detail = 0;
+        int recursive = 0;
+        int i;
+        for(i=1; zLeft[i]; i++){
+          if( zLeft[i]=='r' ) recursive = 1;
+          if( zLeft[i]=='d' ) detail = 1;
+        }
+        decode_trunk_page(iStart, pagesize, detail, recursive);
+        continue;
       }else{
         iEnd = iStart;
       }