Initial commit

Signed-off-by: Mavridis Philippe <[email protected]>

1 files changed, 553 insertions, 0 deletions

diff --git a/src/sqlite/alter.c b/src/sqlite/alter.c
new file mode 100644
index 0000000..8d852b8
--- /dev/null
+++ b/src/sqlite/alter.c
@@ -0,0 +1,553 @@
+/*
+** 2005 February 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file contains C code routines that used to generate VDBE code
+** that implements the ALTER TABLE command.
+**
+** $Id: alter.c,v 1.1.1.1 2006/02/03 20:35:16 hoganrobert Exp $
+*/
+#include "sqliteInt.h"
+#include <ctype.h>
+
+/*
+** The code in this file only exists if we are not omitting the
+** ALTER TABLE logic from the build.
+*/
+#ifndef SQLITE_OMIT_ALTERTABLE
+
+
+/*
+** This function is used by SQL generated to implement the 
+** ALTER TABLE command. The first argument is the text of a CREATE TABLE or
+** CREATE INDEX command. The second is a table name. The table name in 
+** the CREATE TABLE or CREATE INDEX statement is replaced with the second
+** argument and the result returned. Examples:
+**
+** sqlite_rename_table('CREATE TABLE abc(a, b, c)', 'def')
+**     -> 'CREATE TABLE def(a, b, c)'
+**
+** sqlite_rename_table('CREATE INDEX i ON abc(a)', 'def')
+**     -> 'CREATE INDEX i ON def(a, b, c)'
+*/
+static void renameTableFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  unsigned char const *zSql = sqlite3_value_text(argv[0]);
+  unsigned char const *zTableName = sqlite3_value_text(argv[1]);
+
+  int token;
+  Token tname;
+  char const *zCsr = zSql;
+  int len = 0;
+  char *zRet;
+
+  /* The principle used to locate the table name in the CREATE TABLE 
+  ** statement is that the table name is the first token that is immediatedly
+  ** followed by a left parenthesis - TK_LP.
+  */
+  if( zSql ){
+    do {
+      /* Store the token that zCsr points to in tname. */
+      tname.z = zCsr;
+      tname.n = len;
+
+      /* Advance zCsr to the next token. Store that token type in 'token',
+      ** and it's length in 'len' (to be used next iteration of this loop).
+      */
+      do {
+        zCsr += len;
+        len = sqlite3GetToken(zCsr, &token);
+      } while( token==TK_SPACE );
+      assert( len>0 );
+    } while( token!=TK_LP );
+
+    zRet = sqlite3MPrintf("%.*s%Q%s", tname.z - zSql, zSql, 
+       zTableName, tname.z+tname.n);
+    sqlite3_result_text(context, zRet, -1, sqlite3FreeX);
+  }
+}
+
+#ifndef SQLITE_OMIT_TRIGGER
+/* This function is used by SQL generated to implement the ALTER TABLE
+** ALTER TABLE command. The first argument is the text of a CREATE TRIGGER 
+** statement. The second is a table name. The table name in the CREATE 
+** TRIGGER statement is replaced with the second argument and the result 
+** returned. This is analagous to renameTableFunc() above, except for CREATE
+** TRIGGER, not CREATE INDEX and CREATE TABLE.
+*/
+static void renameTriggerFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  unsigned char const *zSql = sqlite3_value_text(argv[0]);
+  unsigned char const *zTableName = sqlite3_value_text(argv[1]);
+
+  int token;
+  Token tname;
+  int dist = 3;
+  char const *zCsr = zSql;
+  int len = 0;
+  char *zRet;
+
+  /* The principle used to locate the table name in the CREATE TRIGGER 
+  ** statement is that the table name is the first token that is immediatedly
+  ** preceded by either TK_ON or TK_DOT and immediatedly followed by one
+  ** of TK_WHEN, TK_BEGIN or TK_FOR.
+  */
+  if( zSql ){
+    do {
+      /* Store the token that zCsr points to in tname. */
+      tname.z = zCsr;
+      tname.n = len;
+
+      /* Advance zCsr to the next token. Store that token type in 'token',
+      ** and it's length in 'len' (to be used next iteration of this loop).
+      */
+      do {
+        zCsr += len;
+        len = sqlite3GetToken(zCsr, &token);
+      }while( token==TK_SPACE );
+      assert( len>0 );
+
+      /* Variable 'dist' stores the number of tokens read since the most
+      ** recent TK_DOT or TK_ON. This means that when a WHEN, FOR or BEGIN 
+      ** token is read and 'dist' equals 2, the condition stated above
+      ** to be met.
+      **
+      ** Note that ON cannot be a database, table or column name, so
+      ** there is no need to worry about syntax like 
+      ** "CREATE TRIGGER ... ON ON.ON BEGIN ..." etc.
+      */
+      dist++;
+      if( token==TK_DOT || token==TK_ON ){
+        dist = 0;
+      }
+    } while( dist!=2 || (token!=TK_WHEN && token!=TK_FOR && token!=TK_BEGIN) );
+
+    /* Variable tname now contains the token that is the old table-name
+    ** in the CREATE TRIGGER statement.
+    */
+    zRet = sqlite3MPrintf("%.*s%Q%s", tname.z - zSql, zSql, 
+       zTableName, tname.z+tname.n);
+    sqlite3_result_text(context, zRet, -1, sqlite3FreeX);
+  }
+}
+#endif   /* !SQLITE_OMIT_TRIGGER */
+
+/*
+** Register built-in functions used to help implement ALTER TABLE
+*/
+void sqlite3AlterFunctions(sqlite3 *db){
+  static const struct {
+     char *zName;
+     signed char nArg;
+     void (*xFunc)(sqlite3_context*,int,sqlite3_value **);
+  } aFuncs[] = {
+    { "sqlite_rename_table",    2, renameTableFunc},
+#ifndef SQLITE_OMIT_TRIGGER
+    { "sqlite_rename_trigger",  2, renameTriggerFunc},
+#endif
+  };
+  int i;
+
+  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
+    sqlite3_create_function(db, aFuncs[i].zName, aFuncs[i].nArg,
+        SQLITE_UTF8, 0, aFuncs[i].xFunc, 0, 0);
+  }
+}
+
+/*
+** Generate the text of a WHERE expression which can be used to select all
+** temporary triggers on table pTab from the sqlite_temp_master table. If
+** table pTab has no temporary triggers, or is itself stored in the 
+** temporary database, NULL is returned.
+*/
+static char *whereTempTriggers(Parse *pParse, Table *pTab){
+  Trigger *pTrig;
+  char *zWhere = 0;
+  char *tmp = 0;
+  if( pTab->iDb!=1 ){
+    for( pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext ){
+      if( pTrig->iDb==1 ){
+        if( !zWhere ){
+          zWhere = sqlite3MPrintf("name=%Q", pTrig->name);
+        }else{
+          tmp = zWhere;
+          zWhere = sqlite3MPrintf("%s OR name=%Q", zWhere, pTrig->name);
+          sqliteFree(tmp);
+        }
+      }
+    }
+  }
+  return zWhere;
+}
+
+/*
+** Generate code to drop and reload the internal representation of table
+** pTab from the database, including triggers and temporary triggers.
+** Argument zName is the name of the table in the database schema at
+** the time the generated code is executed. This can be different from
+** pTab->zName if this function is being called to code part of an 
+** "ALTER TABLE RENAME TO" statement.
+*/
+static void reloadTableSchema(Parse *pParse, Table *pTab, const char *zName){
+  Vdbe *v;
+  char *zWhere;
+  int iDb;
+#ifndef SQLITE_OMIT_TRIGGER
+  Trigger *pTrig;
+#endif
+
+  v = sqlite3GetVdbe(pParse);
+  if( !v ) return;
+  iDb = pTab->iDb;
+
+#ifndef SQLITE_OMIT_TRIGGER
+  /* Drop any table triggers from the internal schema. */
+  for(pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext){
+    assert( pTrig->iDb==iDb || pTrig->iDb==1 );
+    sqlite3VdbeOp3(v, OP_DropTrigger, pTrig->iDb, 0, pTrig->name, 0);
+  }
+#endif
+
+  /* Drop the table and index from the internal schema */
+  sqlite3VdbeOp3(v, OP_DropTable, iDb, 0, pTab->zName, 0);
+
+  /* Reload the table, index and permanent trigger schemas. */
+  zWhere = sqlite3MPrintf("tbl_name=%Q", zName);
+  if( !zWhere ) return;
+  sqlite3VdbeOp3(v, OP_ParseSchema, iDb, 0, zWhere, P3_DYNAMIC);
+
+#ifndef SQLITE_OMIT_TRIGGER
+  /* Now, if the table is not stored in the temp database, reload any temp 
+  ** triggers. Don't use IN(...) in case SQLITE_OMIT_SUBQUERY is defined. 
+  */
+  if( (zWhere=whereTempTriggers(pParse, pTab)) ){
+    sqlite3VdbeOp3(v, OP_ParseSchema, 1, 0, zWhere, P3_DYNAMIC);
+  }
+#endif
+}
+
+/*
+** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy" 
+** command. 
+*/
+void sqlite3AlterRenameTable(
+  Parse *pParse,            /* Parser context. */
+  SrcList *pSrc,            /* The table to rename. */
+  Token *pName              /* The new table name. */
+){
+  int iDb;                  /* Database that contains the table */
+  char *zDb;                /* Name of database iDb */
+  Table *pTab;              /* Table being renamed */
+  char *zName = 0;          /* NULL-terminated version of pName */ 
+  sqlite3 *db = pParse->db; /* Database connection */
+  Vdbe *v;
+#ifndef SQLITE_OMIT_TRIGGER
+  char *zWhere = 0;         /* Where clause to locate temp triggers */
+#endif
+  
+  assert( pSrc->nSrc==1 );
+
+  pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
+  if( !pTab ) goto exit_rename_table;
+  iDb = pTab->iDb;
+  zDb = db->aDb[iDb].zName;
+
+  /* Get a NULL terminated version of the new table name. */
+  zName = sqlite3NameFromToken(pName);
+  if( !zName ) goto exit_rename_table;
+
+  /* Check that a table or index named 'zName' does not already exist
+  ** in database iDb. If so, this is an error.
+  */
+  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
+    sqlite3ErrorMsg(pParse, 
+        "there is already another table or index with this name: %s", zName);
+    goto exit_rename_table;
+  }
+
+  /* Make sure it is not a system table being altered, or a reserved name
+  ** that the table is being renamed to.
+  */
+  if( strlen(pTab->zName)>6 && 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7) ){
+    sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
+    goto exit_rename_table;
+  }
+  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
+    goto exit_rename_table;
+  }
+
+#ifndef SQLITE_OMIT_AUTHORIZATION
+  /* Invoke the authorization callback. */
+  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
+    goto exit_rename_table;
+  }
+#endif
+
+  /* Begin a transaction and code the VerifyCookie for database iDb. 
+  ** Then modify the schema cookie (since the ALTER TABLE modifies the
+  ** schema).
+  */
+  v = sqlite3GetVdbe(pParse);
+  if( v==0 ){
+    goto exit_rename_table;
+  }
+  sqlite3BeginWriteOperation(pParse, 0, iDb);
+  sqlite3ChangeCookie(db, v, iDb);
+
+  /* Modify the sqlite_master table to use the new table name. */
+  sqlite3NestedParse(pParse,
+      "UPDATE %Q.%s SET "
+#ifdef SQLITE_OMIT_TRIGGER
+          "sql = sqlite_rename_table(sql, %Q), "
+#else
+          "sql = CASE "
+            "WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
+            "ELSE sqlite_rename_table(sql, %Q) END, "
+#endif
+          "tbl_name = %Q, "
+          "name = CASE "
+            "WHEN type='table' THEN %Q "
+            "WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
+              "'sqlite_autoindex_' || %Q || substr(name, %d+18,10) "
+            "ELSE name END "
+      "WHERE tbl_name=%Q AND "
+          "(type='table' OR type='index' OR type='trigger');", 
+      zDb, SCHEMA_TABLE(iDb), zName, zName, zName, 
+#ifndef SQLITE_OMIT_TRIGGER
+      zName,
+#endif
+      zName, strlen(pTab->zName), pTab->zName
+  );
+
+#ifndef SQLITE_OMIT_AUTOINCREMENT
+  /* If the sqlite_sequence table exists in this database, then update 
+  ** it with the new table name.
+  */
+  if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
+    sqlite3NestedParse(pParse,
+        "UPDATE %Q.sqlite_sequence set name = %Q WHERE name = %Q",
+        zDb, zName, pTab->zName);
+  }
+#endif
+
+#ifndef SQLITE_OMIT_TRIGGER
+  /* If there are TEMP triggers on this table, modify the sqlite_temp_master
+  ** table. Don't do this if the table being ALTERed is itself located in
+  ** the temp database.
+  */
+  if( (zWhere=whereTempTriggers(pParse, pTab)) ){
+    sqlite3NestedParse(pParse, 
+        "UPDATE sqlite_temp_master SET "
+            "sql = sqlite_rename_trigger(sql, %Q), "
+            "tbl_name = %Q "
+            "WHERE %s;", zName, zName, zWhere);
+    sqliteFree(zWhere);
+  }
+#endif
+
+  /* Drop and reload the internal table schema. */
+  reloadTableSchema(pParse, pTab, zName);
+
+exit_rename_table:
+  sqlite3SrcListDelete(pSrc);
+  sqliteFree(zName);
+}
+
+
+/*
+** This function is called after an "ALTER TABLE ... ADD" statement
+** has been parsed. Argument pColDef contains the text of the new
+** column definition.
+**
+** The Table structure pParse->pNewTable was extended to include
+** the new column during parsing.
+*/
+void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
+  Table *pNew;              /* Copy of pParse->pNewTable */
+  Table *pTab;              /* Table being altered */
+  int iDb;                  /* Database number */
+  const char *zDb;          /* Database name */
+  const char *zTab;         /* Table name */
+  char *zCol;               /* Null-terminated column definition */
+  Column *pCol;             /* The new column */
+  Expr *pDflt;              /* Default value for the new column */
+  Vdbe *v;
+
+  if( pParse->nErr ) return;
+  pNew = pParse->pNewTable;
+  assert( pNew );
+
+  iDb = pNew->iDb;
+  zDb = pParse->db->aDb[iDb].zName;
+  zTab = pNew->zName;
+  pCol = &pNew->aCol[pNew->nCol-1];
+  pDflt = pCol->pDflt;
+  pTab = sqlite3FindTable(pParse->db, zTab, zDb);
+  assert( pTab );
+
+  /* If the default value for the new column was specified with a 
+  ** literal NULL, then set pDflt to 0. This simplifies checking
+  ** for an SQL NULL default below.
+  */
+  if( pDflt && pDflt->op==TK_NULL ){
+    pDflt = 0;
+  }
+
+  /* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
+  ** If there is a NOT NULL constraint, then the default value for the
+  ** column must not be NULL.
+  */
+  if( pCol->isPrimKey ){
+    sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
+    return;
+  }
+  if( pNew->pIndex ){
+    sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
+    return;
+  }
+  if( pCol->notNull && !pDflt ){
+    sqlite3ErrorMsg(pParse, 
+        "Cannot add a NOT NULL column with default value NULL");
+    return;
+  }
+
+  /* Ensure the default expression is something that sqlite3ValueFromExpr()
+  ** can handle (i.e. not CURRENT_TIME etc.)
+  */
+  if( pDflt ){
+    sqlite3_value *pVal;
+    if( sqlite3ValueFromExpr(pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
+      /* malloc() has failed */
+      return;
+    }
+    if( !pVal ){
+      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
+      return;
+    }
+    sqlite3ValueFree(pVal);
+  }
+
+  /* Modify the CREATE TABLE statement. */
+  zCol = sqliteStrNDup(pColDef->z, pColDef->n);
+  if( zCol ){
+    char *zEnd = &zCol[pColDef->n-1];
+    while( (zEnd>zCol && *zEnd==';') || isspace(*(unsigned char *)zEnd) ){
+      *zEnd-- = '\0';
+    }
+    sqlite3NestedParse(pParse, 
+        "UPDATE %Q.%s SET "
+          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d,length(sql)) "
+        "WHERE type = 'table' AND name = %Q", 
+      zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
+      zTab
+    );
+    sqliteFree(zCol);
+  }
+
+  /* If the default value of the new column is NULL, then set the file
+  ** format to 2. If the default value of the new column is not NULL,
+  ** the file format becomes 3.
+  */
+  if( (v=sqlite3GetVdbe(pParse)) ){
+    int f = (pDflt?3:2);
+
+    /* Only set the file format to $f if it is currently less than $f. */
+    sqlite3VdbeAddOp(v, OP_ReadCookie, iDb, 1);
+    sqlite3VdbeAddOp(v, OP_Integer, f, 0);
+    sqlite3VdbeAddOp(v, OP_Ge, 0, sqlite3VdbeCurrentAddr(v)+3);
+    sqlite3VdbeAddOp(v, OP_Integer, f, 0);
+    sqlite3VdbeAddOp(v, OP_SetCookie, iDb, 1);
+  }
+
+  /* Reload the schema of the modified table. */
+  reloadTableSchema(pParse, pTab, pTab->zName);
+}
+
+
+/*
+** This function is called by the parser after the table-name in
+** an "ALTER TABLE <table-name> ADD" statement is parsed. Argument 
+** pSrc is the full-name of the table being altered.
+**
+** This routine makes a (partial) copy of the Table structure
+** for the table being altered and sets Parse.pNewTable to point
+** to it. Routines called by the parser as the column definition
+** is parsed (i.e. sqlite3AddColumn()) add the new Column data to 
+** the copy. The copy of the Table structure is deleted by tokenize.c 
+** after parsing is finished.
+**
+** Routine sqlite3AlterFinishAddColumn() will be called to complete
+** coding the "ALTER TABLE ... ADD" statement.
+*/
+void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
+  Table *pNew;
+  Table *pTab;
+  Vdbe *v;
+  int iDb;
+  int i;
+  int nAlloc;
+
+  /* Look up the table being altered. */
+  assert( !pParse->pNewTable );
+  pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
+  if( !pTab ) goto exit_begin_add_column;
+
+  /* Make sure this is not an attempt to ALTER a view. */
+  if( pTab->pSelect ){
+    sqlite3ErrorMsg(pParse, "Cannot add a column to a view");
+    goto exit_begin_add_column;
+  }
+
+  assert( pTab->addColOffset>0 );
+  iDb = pTab->iDb;
+
+  /* Put a copy of the Table struct in Parse.pNewTable for the
+  ** sqlite3AddColumn() function and friends to modify.
+  */
+  pNew = (Table *)sqliteMalloc(sizeof(Table));
+  if( !pNew ) goto exit_begin_add_column;
+  pParse->pNewTable = pNew;
+  pNew->nCol = pTab->nCol;
+  assert( pNew->nCol>0 );
+  nAlloc = (((pNew->nCol-1)/8)*8)+8;
+  assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
+  pNew->aCol = (Column *)sqliteMalloc(sizeof(Column)*nAlloc);
+  pNew->zName = sqliteStrDup(pTab->zName);
+  if( !pNew->aCol || !pNew->zName ){
+    goto exit_begin_add_column;
+  }
+  memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
+  for(i=0; i<pNew->nCol; i++){
+    Column *pCol = &pNew->aCol[i];
+    pCol->zName = sqliteStrDup(pCol->zName);
+    pCol->zType = 0;
+    pCol->pDflt = 0;
+  }
+  pNew->iDb = iDb;
+  pNew->addColOffset = pTab->addColOffset;
+  pNew->nRef = 1;
+
+  /* Begin a transaction and increment the schema cookie.  */
+  sqlite3BeginWriteOperation(pParse, 0, iDb);
+  v = sqlite3GetVdbe(pParse);
+  if( !v ) goto exit_begin_add_column;
+  sqlite3ChangeCookie(pParse->db, v, iDb);
+
+exit_begin_add_column:
+  sqlite3SrcListDelete(pSrc);
+  return;
+}
+#endif  /* SQLITE_ALTER_TABLE */