Add two new sqlite3_db_config() options that enable the ATTACH command

to create new database files and to open databases read/write.  Both
default to on for backwards compatibility.

FossilOrigin-Name: fe0c58d00b491d1af7c0894f5c32542954aeea2e6510853b3bcbf13ac0bf5ce0

5 files changed, 53 insertions, 2 deletions

diff --git a/src/attach.c b/src/attach.c
index 9f23dce1e..399a6cb53 100644
--- a/src/attach.c
+++ b/src/attach.c
@@ -175,6 +175,12 @@ static void attachFunc(
       sqlite3_free(zErr);
       return;
     }
+    if( (db->flags & SQLITE_AttachWrite)==0 ){
+      flags &= ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE);
+      flags |= SQLITE_OPEN_READONLY;
+    }else if( (db->flags & SQLITE_AttachCreate)==0 ){
+      flags &= ~SQLITE_OPEN_CREATE;
+    }
     assert( pVfs );
     flags |= SQLITE_OPEN_MAIN_DB;
     rc = sqlite3BtreeOpen(pVfs, zPath, db, &pNew->pBt, 0, flags);
diff --git a/src/main.c b/src/main.c
index 1163deb6e..943478d6d 100644
--- a/src/main.c
+++ b/src/main.c
@@ -959,7 +959,7 @@ int sqlite3_db_config(sqlite3 *db, int op, ...){
     default: {
       static const struct {
         int op;      /* The opcode */
-        u32 mask;    /* Mask of the bit in sqlite3.flags to set/clear */
+        u64 mask;    /* Mask of the bit in sqlite3.flags to set/clear */
       } aFlagOp[] = {
         { SQLITE_DBCONFIG_ENABLE_FKEY,           SQLITE_ForeignKeys    },
         { SQLITE_DBCONFIG_ENABLE_TRIGGER,        SQLITE_EnableTrigger  },
@@ -980,6 +980,8 @@ int sqlite3_db_config(sqlite3 *db, int op, ...){
         { SQLITE_DBCONFIG_TRUSTED_SCHEMA,        SQLITE_TrustedSchema  },
         { SQLITE_DBCONFIG_STMT_SCANSTATUS,       SQLITE_StmtScanStatus },
         { SQLITE_DBCONFIG_REVERSE_SCANORDER,     SQLITE_ReverseOrder   },
+        { SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE,  SQLITE_AttachCreate   },
+        { SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE,   SQLITE_AttachWrite    },
       };
       unsigned int i;
       rc = SQLITE_ERROR; /* IMP: R-42790-23372 */
@@ -3321,6 +3323,8 @@ static int openDatabase(
                  | SQLITE_EnableTrigger
                  | SQLITE_EnableView
                  | SQLITE_CacheSpill
+                 | SQLITE_AttachCreate
+                 | SQLITE_AttachWrite
 #if !defined(SQLITE_TRUSTED_SCHEMA) || SQLITE_TRUSTED_SCHEMA+0!=0
                  | SQLITE_TrustedSchema
 #endif
diff --git a/src/shell.c.in b/src/shell.c.in
index d7a0bf55b..be6508fb1 100644
--- a/src/shell.c.in
+++ b/src/shell.c.in
@@ -8725,6 +8725,8 @@ static int do_meta_command(char *zLine, ShellState *p){
       const char *zName;
       int op;
     } aDbConfig[] = {
+        { "attach_create",      SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE  },
+        { "attach_write",       SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE   },
         { "defensive",          SQLITE_DBCONFIG_DEFENSIVE             },
         { "dqs_ddl",            SQLITE_DBCONFIG_DQS_DDL               },
         { "dqs_dml",            SQLITE_DBCONFIG_DQS_DML               },
diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 9a117fa54..46336bf3e 100644
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -2523,6 +2523,41 @@ struct sqlite3_mem_methods {
 ** first argument.
 ** </dd>
 **
+** [[SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE]]
+** <dt>SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE</dt>
+** <dd>The SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE option enables the ability
+** of the [ATTACH DATABASE] SQL command to create a new database if the
+** database filed named by the SQL command does not already exist.  This
+** ability of [ATTACH] to create a new database is enabled by default, but
+** can be disabled, using the current DBCONFIG option if desired.
+** This option takes two arguments which are an integer and a pointer
+** to an integer.  The first argument is 1, 0, or -1 to enable, disable, or
+** leave unchanged the attach-create flag, respectively.  If the second
+** argument is not NULL, then 0 or 1 is written into the integer that the
+** second argument points to depending on if the attach-create flag is set
+** after processing the first argument. 
+** </dd>
+**
+** [[SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE]]
+** <dt>SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE</dt>
+** <dd>The SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE option enables the ability
+** of the [ATTACH DATABASE] SQL command to create a new database that is
+** open for writing.  This capability is enabled by default, but
+** can be disabled, using the current DBCONFIG option if desired.  If this
+** capability is disabled, the [ATTACH] command will still work, but the
+** database is opened read-only.  If this option is disabled, then the
+** ability to create a new database using [ATTACH] is also disabled,
+** regardless of the value of the [SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE]
+** option.
+** This option takes two arguments which are an integer and a pointer
+** to an integer.  The first argument is 1, 0, or -1 to enable, disable, or
+** leave unchanged the ability to ATTACH another database for writing,
+** respectively.  If the second argument is not NULL, then 0 or 1 is written
+** into the integer that the second argument points to depending on if the
+** ability to ATTACH a read/write database is set
+** after processing the first argument.
+** </dd>
+**
 ** </dl>
 */
 #define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
@@ -2545,7 +2580,9 @@ struct sqlite3_mem_methods {
 #define SQLITE_DBCONFIG_TRUSTED_SCHEMA        1017 /* int int* */
 #define SQLITE_DBCONFIG_STMT_SCANSTATUS       1018 /* int int* */
 #define SQLITE_DBCONFIG_REVERSE_SCANORDER     1019 /* int int* */
-#define SQLITE_DBCONFIG_MAX                   1019 /* Largest DBCONFIG */
+#define SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE  1020 /* int int* */
+#define SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE   1021 /* int int* */
+#define SQLITE_DBCONFIG_MAX                   1021 /* Largest DBCONFIG */
 
 /*
 ** CAPI3REF: Enable Or Disable Extended Result Codes
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 3045d7c4a..aa7e297e7 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1830,6 +1830,8 @@ struct sqlite3 {
 #define SQLITE_CorruptRdOnly  HI(0x00002) /* Prohibit writes due to error */
 #define SQLITE_ReadUncommit   HI(0x00004) /* READ UNCOMMITTED in shared-cache */
 #define SQLITE_FkNoAction     HI(0x00008) /* Treat all FK as NO ACTION */
+#define SQLITE_AttachCreate   HI(0x00010) /* ATTACH allowed to create new dbs */
+#define SQLITE_AttachWrite    HI(0x00020) /* ATTACH allowed to open for write */
 
 /* Flags used only if debugging */
 #ifdef SQLITE_DEBUG