From 3350ce95f7d754c8b8de51c926b870d06f9ee7ad Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Thu, 6 Feb 2014 00:49:12 +0000
Subject: [PATCH] Add the ".repair" command to the command-line shell.

FossilOrigin-Name: d1dfadea87ecf18eeb6d2f21769deaa97473ca0e
---
 manifest      |  14 ++--
 manifest.uuid |   2 +-
 src/shell.c   | 194 ++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 202 insertions(+), 8 deletions(-)

diff --git a/manifest b/manifest
index da13307c6c..c624ecece4 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C In\sthe\sWin32\sVFS,\sthe\swinSysInfo\svariable\sshould\sbe\sstatic.
-D 2014-02-05T11:05:47.687
+C Add\sthe\s".repair"\scommand\sto\sthe\scommand-line\sshell.
+D 2014-02-06T00:49:12.328
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 2ef13430cd359f7b361bb863504e227b25cc7f81
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -220,7 +220,7 @@ F src/random.c d10c1f85b6709ca97278428fd5db5bbb9c74eece
 F src/resolve.c 7eda9097b29fcf3d2b42fdc17d1de672134e09b6
 F src/rowset.c 64655f1a627c9c212d9ab497899e7424a34222e0
 F src/select.c b78f5e62c283aca2e38657938bc1fec1051df728
-F src/shell.c 24722d24d4ea8ca93db35e44db7308de786767ca
+F src/shell.c c128bf92b3ed268d8ec6f0df275a5d737edf2968
 F src/sqlite.h.in eed7f7d66a60daaa7b4a597dcd9bad87aad9611b
 F src/sqlite3.rc 11094cc6a157a028b301a9f06b3d03089ea37c3e
 F src/sqlite3ext.h 886f5a34de171002ad46fae8c36a7d8051c190fc
@@ -1152,7 +1152,7 @@ F tool/vdbe-compress.tcl 0cf56e9263a152b84da86e75a5c0cdcdb7a47891
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh d1a6de74685f360ab718efda6265994b99bbea01
 F tool/win/sqlite.vsix 030f3eeaf2cb811a3692ab9c14d021a75ce41fff
-P f2504089df0bf4011864e67825b37f6aa3d03458
-R f919fd88b0fe2a17b41d9c03ff44720f
-U mistachkin
-Z fecb65c3944a970d4d7662e030506246
+P 4a4dd371a72b7d475185923bebb4cd9bd83e1bd9
+R 235c07c6649435d22d14c7aa202be2ed
+U drh
+Z b9d162ba79528a4d7df551b82e7b6e75
diff --git a/manifest.uuid b/manifest.uuid
index e178daa36c..98d249ad3e 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-4a4dd371a72b7d475185923bebb4cd9bd83e1bd9
\ No newline at end of file
+d1dfadea87ecf18eeb6d2f21769deaa97473ca0e
\ No newline at end of file
diff --git a/src/shell.c b/src/shell.c
index 1c4c4ad3e3..68f2ef2afc 100644
--- a/src/shell.c
+++ b/src/shell.c
@@ -1581,6 +1581,7 @@ static char zHelp[] =
   ".prompt MAIN CONTINUE  Replace the standard prompts\n"
   ".quit                  Exit this program\n"
   ".read FILENAME         Execute SQL in FILENAME\n"
+  ".repair NEWDB          Recover data into NEWDB from a corrupt database\n"
   ".restore ?DB? FILE     Restore content of DB (default \"main\") from FILE\n"
   ".schema ?TABLE?        Show the CREATE statements\n"
   "                         If TABLE specified, only show tables matching\n"
@@ -1896,6 +1897,195 @@ static char *csv_read_one_field(CSVReader *p){
   return p->z;
 }
 
+/*
+** Try to transfer data for table zTable
+*/
+static void tryToRepairData(
+  struct callback_data *p,
+  sqlite3 *newDb,
+  const char *zTable
+){
+  sqlite3_stmt *pQuery = 0; 
+  sqlite3_stmt *pInsert = 0;
+  char *zQuery = 0;
+  char *zInsert = 0;
+  int rc;
+  int i, j, n;
+  int nTable = (int)strlen(zTable);
+  int k = 0;
+
+  zQuery = sqlite3_mprintf("SELECT * FROM \"%w\"", zTable);
+  rc = sqlite3_prepare_v2(p->db, zQuery, -1, &pQuery, 0);
+  if( rc ){
+    fprintf(stderr, "Error: (%d) %s on [%s]\n",
+            sqlite3_extended_errcode(p->db), sqlite3_errmsg(p->db),
+            zQuery);
+    goto end_data_xfer;
+  }
+  n = sqlite3_column_count(pQuery);
+  zInsert = sqlite3_malloc(200 + nTable + n*3);
+  if( zInsert==0 ){
+    fprintf(stderr, "out of memory\n");
+    goto end_data_xfer;
+  }
+  sqlite3_snprintf(200+nTable,zInsert,
+                   "INSERT OR IGNORE INTO \"%s\" VALUES(?", zTable);
+  i = (int)strlen(zInsert);
+  for(j=1; j<n; j++){
+    memcpy(zInsert+i, ",?", 2);
+    i += 2;
+  }
+  memcpy(zInsert+i, ");", 3);
+  rc = sqlite3_prepare_v2(newDb, zInsert, -1, &pInsert, 0);
+  if( rc ){
+    fprintf(stderr, "Error: (%d) %s on [%s]\n",
+            sqlite3_extended_errcode(newDb), sqlite3_errmsg(newDb),
+            zQuery);
+    goto end_data_xfer;
+  }
+  for(k=0; k<2; k++){
+    while( (rc = sqlite3_step(pQuery))==SQLITE_ROW ){
+      for(i=0; i<n; i++){
+        switch( sqlite3_column_type(pQuery, i) ){
+          case SQLITE_NULL: {
+            sqlite3_bind_null(pInsert, i+1);
+            break;
+          }
+          case SQLITE_INTEGER: {
+            sqlite3_bind_int64(pInsert, i+1, sqlite3_column_int64(pQuery,i));
+            break;
+          }
+          case SQLITE_FLOAT: {
+            sqlite3_bind_double(pInsert, i+1, sqlite3_column_double(pQuery,i));
+            break;
+          }
+          case SQLITE_TEXT: {
+            sqlite3_bind_text(pInsert, i+1,
+                             (const char*)sqlite3_column_text(pQuery,i),
+                             -1, SQLITE_STATIC);
+            break;
+          }
+          case SQLITE_BLOB: {
+            sqlite3_bind_blob(pInsert, i+1, sqlite3_column_blob(pQuery,i),
+                                            sqlite3_column_bytes(pQuery,i),
+                                            SQLITE_STATIC);
+            break;
+          }
+        }
+      } /* End for */
+      sqlite3_step(pInsert);
+      sqlite3_reset(pInsert);
+    } /* End while */
+    if( rc==SQLITE_DONE ) break;
+    sqlite3_finalize(pQuery);
+    sqlite3_free(zQuery);
+    zQuery = sqlite3_mprintf("SELECT * FROM \"%w\" ORDER BY rowid DESC;",
+                             zTable);
+    rc = sqlite3_prepare_v2(p->db, zQuery, -1, &pQuery, 0);
+    if( rc ){
+       fprintf(stderr, "Error: (%d) %s on [%s]\n",
+          sqlite3_extended_errcode(p->db), sqlite3_errmsg(p->db),
+          zQuery);
+       goto end_data_xfer;
+    }
+  } /* End for(k=0...) */
+
+end_data_xfer:
+  sqlite3_finalize(pQuery);
+  sqlite3_finalize(pInsert);
+  sqlite3_free(zQuery);
+  sqlite3_free(zInsert);
+}
+
+
+/*
+** Try to transfer all rows of the schema that match zWhere.  For
+** each row, invoke xForEach() on the object defined by that row.
+*/
+static void tryToRepairSchema(
+  struct callback_data *p,
+  sqlite3 *newDb,
+  const char *zWhere,
+  void (*xForEach)(struct callback_data*,sqlite3*,const char*)
+){
+  sqlite3_stmt *pQuery = 0;
+  char *zQuery = 0;
+  int rc;
+  const unsigned char *zName;
+  const unsigned char *zSql;
+
+  zQuery = sqlite3_mprintf("SELECT name, sql FROM sqlite_master"
+                           " WHERE %s", zWhere);
+  rc = sqlite3_prepare_v2(p->db, zQuery, -1, &pQuery, 0);
+  if( rc ){
+    fprintf(stderr, "Error: (%d) %s on [%s]\n",
+                    sqlite3_extended_errcode(p->db), sqlite3_errmsg(p->db),
+                    zQuery);
+    goto end_schema_xfer;
+  }
+  while( (rc = sqlite3_step(pQuery))==SQLITE_ROW ){
+    zName = sqlite3_column_text(pQuery, 0);
+    zSql = sqlite3_column_text(pQuery, 1);
+    printf("%s... ", zName); fflush(stdout);
+    sqlite3_exec(newDb, (const char*)zSql, 0, 0, 0);
+    if( xForEach ){
+      xForEach(p, newDb, (const char*)zName);
+    }
+    printf("done\n");
+  }
+  if( rc!=SQLITE_DONE ){
+    sqlite3_finalize(pQuery);
+    sqlite3_free(zQuery);
+    zQuery = sqlite3_mprintf("SELECT name, sql FROM sqlite_master"
+                             " WHERE %s ORDER BY rowid DESC", zWhere);
+    rc = sqlite3_prepare_v2(p->db, zQuery, -1, &pQuery, 0);
+    if( rc ){
+      fprintf(stderr, "Error: (%d) %s on [%s]\n",
+                      sqlite3_extended_errcode(p->db), sqlite3_errmsg(p->db),
+                      zQuery);
+      goto end_schema_xfer;
+    }
+    while( (rc = sqlite3_step(pQuery))==SQLITE_ROW ){
+      zName = sqlite3_column_text(pQuery, 0);
+      zSql = sqlite3_column_text(pQuery, 1);
+      printf("%s... ", zName); fflush(stdout);
+      sqlite3_exec(newDb, (const char*)zSql, 0, 0, 0);
+      if( xForEach ){
+        xForEach(p, newDb, (const char*)zName);
+      }
+      printf("done\n");
+    }
+  }
+end_schema_xfer:
+  sqlite3_finalize(pQuery);
+  sqlite3_free(zQuery);
+}
+
+/*
+** Open a new database file named "zNewDb".  Try to recover as much information
+** as possible out of the main database (which might be corrupt) and write it
+** into zNewDb.
+*/
+static void tryToRepair(struct callback_data *p, const char *zNewDb){
+  int rc;
+  sqlite3 *newDb = 0;
+  if( access(zNewDb,0)==0 ){
+    fprintf(stderr, "File \"%s\" already exists.\n", zNewDb);
+    return;
+  }
+  rc = sqlite3_open(zNewDb, &newDb);
+  if( rc ){
+    fprintf(stderr, "Cannot create output database: %s\n",
+            sqlite3_errmsg(newDb));
+  }else{
+    sqlite3_exec(newDb, "BEGIN EXCLUSIVE;", 0, 0, 0);
+    tryToRepairSchema(p, newDb, "type='table'", tryToRepairData);
+    tryToRepairSchema(p, newDb, "type!='table'", 0);
+    sqlite3_exec(newDb, "COMMIT;", 0, 0, 0);
+  }
+  sqlite3_close(newDb);
+}
+
 /*
 ** If an input line begins with "." then invoke this routine to
 ** process that line.
@@ -2495,6 +2685,10 @@ static int do_meta_command(char *zLine, struct callback_data *p){
     }
   }else
 
+  if( c=='r' && strncmp(azArg[0], "repair", n)==0 && nArg>1 && nArg<3 ){
+    tryToRepair(p, azArg[1]);
+  }else
+
   if( c=='r' && n>=3 && strncmp(azArg[0], "restore", n)==0 && nArg>1 && nArg<4){
     const char *zSrcFile;
     const char *zDb;