BSON Library from TPT/MongoDB

1 files changed, 1122 insertions, 0 deletions

diff --git a/src/bson/BSON.cpp b/src/bson/BSON.cpp
new file mode 100644
index 0000000..634290c
--- /dev/null
+++ b/src/bson/BSON.cpp
@@ -0,0 +1,1122 @@
+/* bson.c */
+
+/*    Copyright 2009, 2010 10gen Inc.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <time.h>
+#include <limits.h>
+
+#include "BSON.h"
+
+const int initialBufferSize = 128;
+
+/* only need one of these */
+static const int zero = 0;
+
+/* Custom standard function pointers. */
+void *( *bson_malloc_func )( size_t ) = malloc;
+void *( *bson_realloc_func )( void *, size_t ) = realloc;
+void  ( *bson_free )( void * ) = free;
+bson_printf_func bson_printf = printf;
+bson_fprintf_func bson_fprintf = fprintf;
+bson_sprintf_func bson_sprintf = sprintf;
+
+static int _bson_errprintf( const char *, ... );
+bson_printf_func bson_errprintf = _bson_errprintf;
+
+/* ObjectId fuzz functions. */
+static int ( *oid_fuzz_func )( void ) = NULL;
+static int ( *oid_inc_func )( void )  = NULL;
+
+/* ----------------------------
+   READING
+   ------------------------------ */
+
+bson *bson_empty( bson *obj ) {
+    static char *data = "\005\0\0\0\0";
+    bson_init_data( obj, data );
+    obj->finished = 1;
+    obj->err = 0;
+    obj->stackPos = 0;
+    return obj;
+}
+
+int bson_copy( bson *out, const bson *in ) {
+    if ( !out ) return BSON_ERROR;
+    if ( !in->finished ) return BSON_ERROR;
+    bson_init_size( out, bson_size( in ) );
+    memcpy( out->data, in->data, bson_size( in ) );
+    out->finished = 1;
+
+    return BSON_OK;
+}
+
+int bson_init_data( bson *b, char *data ) {
+    b->data = data;
+    return BSON_OK;
+}
+
+int bson_init_finished_data( bson *b, char *data ) {
+    bson_init_data( b, data );
+    b->stackPos = 0;
+    b->finished = 1;
+    return BSON_OK;
+}
+
+static void _bson_reset( bson *b ) {
+    b->finished = 0;
+    b->stackPos = 0;
+    b->err = 0;
+    b->errstr = NULL;
+}
+
+int bson_size( const bson *b ) {
+    int i;
+    if ( ! b || ! b->data )
+        return 0;
+    bson_little_endian32( &i, b->data );
+    return i;
+}
+
+const char *bson_data( bson *b ) {
+    return (const char *)b->data;
+}
+
+static char hexbyte( char hex ) {
+    switch ( hex ) {
+    case '0':
+        return 0x0;
+    case '1':
+        return 0x1;
+    case '2':
+        return 0x2;
+    case '3':
+        return 0x3;
+    case '4':
+        return 0x4;
+    case '5':
+        return 0x5;
+    case '6':
+        return 0x6;
+    case '7':
+        return 0x7;
+    case '8':
+        return 0x8;
+    case '9':
+        return 0x9;
+    case 'a':
+    case 'A':
+        return 0xa;
+    case 'b':
+    case 'B':
+        return 0xb;
+    case 'c':
+    case 'C':
+        return 0xc;
+    case 'd':
+    case 'D':
+        return 0xd;
+    case 'e':
+    case 'E':
+        return 0xe;
+    case 'f':
+    case 'F':
+        return 0xf;
+    default:
+        return 0x0; /* something smarter? */
+    }
+}
+
+void bson_oid_from_string( bson_oid_t *oid, const char *str ) {
+    int i;
+    for ( i=0; i<12; i++ ) {
+        oid->bytes[i] = ( hexbyte( str[2*i] ) << 4 ) | hexbyte( str[2*i + 1] );
+    }
+}
+
+void bson_oid_to_string( const bson_oid_t *oid, char *str ) {
+    static const char hex[16] = {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'};
+    int i;
+    for ( i=0; i<12; i++ ) {
+        str[2*i]     = hex[( oid->bytes[i] & 0xf0 ) >> 4];
+        str[2*i + 1] = hex[ oid->bytes[i] & 0x0f      ];
+    }
+    str[24] = '\0';
+}
+
+void bson_set_oid_fuzz( int ( *func )( void ) ) {
+    oid_fuzz_func = func;
+}
+
+void bson_set_oid_inc( int ( *func )( void ) ) {
+    oid_inc_func = func;
+}
+
+void bson_oid_gen( bson_oid_t *oid ) {
+    static int incr = 0;
+    static int fuzz = 0;
+    int i;
+    int t = time( NULL );
+
+    if( oid_inc_func )
+        i = oid_inc_func();
+    else
+        i = incr++;
+
+    if ( !fuzz ) {
+        if ( oid_fuzz_func )
+            fuzz = oid_fuzz_func();
+        else {
+            srand( t );
+            fuzz = rand();
+        }
+    }
+
+    bson_big_endian32( &oid->ints[0], &t );
+    oid->ints[1] = fuzz;
+    bson_big_endian32( &oid->ints[2], &i );
+}
+
+time_t bson_oid_generated_time( bson_oid_t *oid ) {
+    time_t out;
+    bson_big_endian32( &out, &oid->ints[0] );
+
+    return out;
+}
+
+void bson_print( bson *b ) {
+    bson_print_raw( b->data , 0 );
+}
+
+void bson_print_raw( const char *data , int depth ) {
+    bson_iterator i;
+    const char *key;
+    int temp;
+    bson_timestamp_t ts;
+    char oidhex[25];
+    bson scope;
+    bson_iterator_from_buffer( &i, data );
+
+    while ( bson_iterator_next( &i ) ) {
+        bson_type t = bson_iterator_type( &i );
+        if ( t == 0 )
+            break;
+        key = bson_iterator_key( &i );
+
+        for ( temp=0; temp<=depth; temp++ )
+            bson_printf( "\t" );
+        bson_printf( "%s : %d \t " , key , t );
+        switch ( t ) {
+        case BSON_DOUBLE:
+            bson_printf( "%f" , bson_iterator_double( &i ) );
+            break;
+        case BSON_STRING:
+            bson_printf( "%s" , bson_iterator_string( &i ) );
+            break;
+        case BSON_SYMBOL:
+            bson_printf( "SYMBOL: %s" , bson_iterator_string( &i ) );
+            break;
+        case BSON_OID:
+            bson_oid_to_string( bson_iterator_oid( &i ), oidhex );
+            bson_printf( "%s" , oidhex );
+            break;
+        case BSON_BOOL:
+            bson_printf( "%s" , bson_iterator_bool( &i ) ? "true" : "false" );
+            break;
+        case BSON_DATE:
+            bson_printf( "%ld" , ( long int )bson_iterator_date( &i ) );
+            break;
+        case BSON_BINDATA:
+            bson_printf( "BSON_BINDATA" );
+            break;
+        case BSON_UNDEFINED:
+            bson_printf( "BSON_UNDEFINED" );
+            break;
+        case BSON_NULL:
+            bson_printf( "BSON_NULL" );
+            break;
+        case BSON_REGEX:
+            bson_printf( "BSON_REGEX: %s", bson_iterator_regex( &i ) );
+            break;
+        case BSON_CODE:
+            bson_printf( "BSON_CODE: %s", bson_iterator_code( &i ) );
+            break;
+        case BSON_CODEWSCOPE:
+            bson_printf( "BSON_CODE_W_SCOPE: %s", bson_iterator_code( &i ) );
+            bson_init( &scope );
+            bson_iterator_code_scope( &i, &scope );
+            bson_printf( "\n\t SCOPE: " );
+            bson_print( &scope );
+            break;
+        case BSON_INT:
+            bson_printf( "%d" , bson_iterator_int( &i ) );
+            break;
+        case BSON_LONG:
+            bson_printf( "%lld" , ( uint64_t )bson_iterator_long( &i ) );
+            break;
+        case BSON_TIMESTAMP:
+            ts = bson_iterator_timestamp( &i );
+            bson_printf( "i: %d, t: %d", ts.i, ts.t );
+            break;
+        case BSON_OBJECT:
+        case BSON_ARRAY:
+            bson_printf( "\n" );
+            bson_print_raw( bson_iterator_value( &i ) , depth + 1 );
+            break;
+        default:
+            bson_errprintf( "can't print type : %d\n" , t );
+        }
+        bson_printf( "\n" );
+    }
+}
+
+/* ----------------------------
+   ITERATOR
+   ------------------------------ */
+
+void bson_iterator_init( bson_iterator *i, const bson *b ) {
+    i->cur = b->data + 4;
+    i->first = 1;
+}
+
+void bson_iterator_from_buffer( bson_iterator *i, const char *buffer ) {
+    i->cur = buffer + 4;
+    i->first = 1;
+}
+
+bson_type bson_find( bson_iterator *it, const bson *obj, const char *name ) {
+    bson_iterator_init( it, (bson *)obj );
+    while( bson_iterator_next( it ) ) {
+        if ( strcmp( name, bson_iterator_key( it ) ) == 0 )
+            break;
+    }
+    return bson_iterator_type( it );
+}
+
+bson_bool_t bson_iterator_more( const bson_iterator *i ) {
+    return *( i->cur );
+}
+
+bson_type bson_iterator_next( bson_iterator *i ) {
+    int ds;
+
+    if ( i->first ) {
+        i->first = 0;
+        return ( bson_type )( *i->cur );
+    }
+
+    switch ( bson_iterator_type( i ) ) {
+    case BSON_EOO:
+        return BSON_EOO; /* don't advance */
+    case BSON_UNDEFINED:
+    case BSON_NULL:
+        ds = 0;
+        break;
+    case BSON_BOOL:
+        ds = 1;
+        break;
+    case BSON_INT:
+        ds = 4;
+        break;
+    case BSON_LONG:
+    case BSON_DOUBLE:
+    case BSON_TIMESTAMP:
+    case BSON_DATE:
+        ds = 8;
+        break;
+    case BSON_OID:
+        ds = 12;
+        break;
+    case BSON_STRING:
+    case BSON_SYMBOL:
+    case BSON_CODE:
+        ds = 4 + bson_iterator_int_raw( i );
+        break;
+    case BSON_BINDATA:
+        ds = 5 + bson_iterator_int_raw( i );
+        break;
+    case BSON_OBJECT:
+    case BSON_ARRAY:
+    case BSON_CODEWSCOPE:
+        ds = bson_iterator_int_raw( i );
+        break;
+    case BSON_DBREF:
+        ds = 4+12 + bson_iterator_int_raw( i );
+        break;
+    case BSON_REGEX: {
+        const char *s = bson_iterator_value( i );
+        const char *p = s;
+        p += strlen( p )+1;
+        p += strlen( p )+1;
+        ds = p-s;
+        break;
+    }
+
+    default: {
+        char msg[] = "unknown type: 000000000000";
+        bson_numstr( msg+14, ( unsigned )( i->cur[0] ) );
+        bson_fatal_msg( 0, msg );
+        return (bson_type)0;
+    }
+    }
+
+    i->cur += 1 + strlen( i->cur + 1 ) + 1 + ds;
+
+    return ( bson_type )( *i->cur );
+}
+
+bson_type bson_iterator_type( const bson_iterator *i ) {
+    return ( bson_type )i->cur[0];
+}
+
+const char *bson_iterator_key( const bson_iterator *i ) {
+    return i->cur + 1;
+}
+
+const char *bson_iterator_value( const bson_iterator *i ) {
+    const char *t = i->cur + 1;
+    t += strlen( t ) + 1;
+    return t;
+}
+
+/* types */
+
+int bson_iterator_int_raw( const bson_iterator *i ) {
+    int out;
+    bson_little_endian32( &out, bson_iterator_value( i ) );
+    return out;
+}
+
+double bson_iterator_double_raw( const bson_iterator *i ) {
+    double out;
+    bson_little_endian64( &out, bson_iterator_value( i ) );
+    return out;
+}
+
+int64_t bson_iterator_long_raw( const bson_iterator *i ) {
+    int64_t out;
+    bson_little_endian64( &out, bson_iterator_value( i ) );
+    return out;
+}
+
+bson_bool_t bson_iterator_bool_raw( const bson_iterator *i ) {
+    return bson_iterator_value( i )[0];
+}
+
+bson_oid_t *bson_iterator_oid( const bson_iterator *i ) {
+    return ( bson_oid_t * )bson_iterator_value( i );
+}
+
+int bson_iterator_int( const bson_iterator *i ) {
+    switch ( bson_iterator_type( i ) ) {
+    case BSON_INT:
+        return bson_iterator_int_raw( i );
+    case BSON_LONG:
+        return bson_iterator_long_raw( i );
+    case BSON_DOUBLE:
+        return bson_iterator_double_raw( i );
+    default:
+        return 0;
+    }
+}
+
+double bson_iterator_double( const bson_iterator *i ) {
+    switch ( bson_iterator_type( i ) ) {
+    case BSON_INT:
+        return bson_iterator_int_raw( i );
+    case BSON_LONG:
+        return bson_iterator_long_raw( i );
+    case BSON_DOUBLE:
+        return bson_iterator_double_raw( i );
+    default:
+        return 0;
+    }
+}
+
+int64_t bson_iterator_long( const bson_iterator *i ) {
+    switch ( bson_iterator_type( i ) ) {
+    case BSON_INT:
+        return bson_iterator_int_raw( i );
+    case BSON_LONG:
+        return bson_iterator_long_raw( i );
+    case BSON_DOUBLE:
+        return bson_iterator_double_raw( i );
+    default:
+        return 0;
+    }
+}
+
+bson_timestamp_t bson_iterator_timestamp( const bson_iterator *i ) {
+    bson_timestamp_t ts;
+    bson_little_endian32( &( ts.i ), bson_iterator_value( i ) );
+    bson_little_endian32( &( ts.t ), bson_iterator_value( i ) + 4 );
+    return ts;
+}
+
+bson_bool_t bson_iterator_bool( const bson_iterator *i ) {
+    switch ( bson_iterator_type( i ) ) {
+    case BSON_BOOL:
+        return bson_iterator_bool_raw( i );
+    case BSON_INT:
+        return bson_iterator_int_raw( i ) != 0;
+    case BSON_LONG:
+        return bson_iterator_long_raw( i ) != 0;
+    case BSON_DOUBLE:
+        return bson_iterator_double_raw( i ) != 0;
+    case BSON_EOO:
+    case BSON_NULL:
+        return 0;
+    default:
+        return 1;
+    }
+}
+
+const char *bson_iterator_string( const bson_iterator *i ) {
+    return bson_iterator_value( i ) + 4;
+}
+
+int bson_iterator_string_len( const bson_iterator *i ) {
+    return bson_iterator_int_raw( i );
+}
+
+const char *bson_iterator_code( const bson_iterator *i ) {
+    switch ( bson_iterator_type( i ) ) {
+    case BSON_STRING:
+    case BSON_CODE:
+        return bson_iterator_value( i ) + 4;
+    case BSON_CODEWSCOPE:
+        return bson_iterator_value( i ) + 8;
+    default:
+        return NULL;
+    }
+}
+
+void bson_iterator_code_scope( const bson_iterator *i, bson *scope ) {
+    if ( bson_iterator_type( i ) == BSON_CODEWSCOPE ) {
+        int code_len;
+        bson_little_endian32( &code_len, bson_iterator_value( i )+4 );
+        bson_init_data( scope, (char*)((void *)(bson_iterator_value(i)+8+code_len )));
+        _bson_reset( scope );
+        scope->finished = 1;
+    } else {
+        bson_empty( scope );
+    }
+}
+
+bson_date_t bson_iterator_date( const bson_iterator *i ) {
+    return bson_iterator_long_raw( i );
+}
+
+time_t bson_iterator_time_t( const bson_iterator *i ) {
+    return bson_iterator_date( i ) / 1000;
+}
+
+int bson_iterator_bin_len( const bson_iterator *i ) {
+    return ( bson_iterator_bin_type( i ) == BSON_BIN_BINARY_OLD )
+           ? bson_iterator_int_raw( i ) - 4
+           : bson_iterator_int_raw( i );
+}
+
+char bson_iterator_bin_type( const bson_iterator *i ) {
+    return bson_iterator_value( i )[4];
+}
+
+const char *bson_iterator_bin_data( const bson_iterator *i ) {
+    return ( bson_iterator_bin_type( i ) == BSON_BIN_BINARY_OLD )
+           ? bson_iterator_value( i ) + 9
+           : bson_iterator_value( i ) + 5;
+}
+
+const char *bson_iterator_regex( const bson_iterator *i ) {
+    return bson_iterator_value( i );
+}
+
+const char *bson_iterator_regex_opts( const bson_iterator *i ) {
+    const char *p = bson_iterator_value( i );
+    return p + strlen( p ) + 1;
+
+}
+
+void bson_iterator_subobject( const bson_iterator *i, bson *sub ) {
+    bson_init_data( sub, ( char * )bson_iterator_value( i ) );
+    _bson_reset( sub );
+    sub->finished = 1;
+}
+
+void bson_iterator_subiterator( const bson_iterator *i, bson_iterator *sub ) {
+    bson_iterator_from_buffer( sub, bson_iterator_value( i ) );
+}
+
+/* ----------------------------
+   BUILDING
+   ------------------------------ */
+
+static void _bson_init_size( bson *b, int size ) {
+    if( size == 0 )
+        b->data = NULL;
+    else
+        b->data = ( char * )bson_malloc( size );
+    b->dataSize = size;
+    b->cur = b->data + 4;
+    _bson_reset( b );
+}
+
+void bson_init( bson *b ) {
+    _bson_init_size( b, initialBufferSize );
+}
+
+void bson_init_size( bson *b, int size ) {
+    _bson_init_size( b, size );
+}
+
+static void bson_append_byte( bson *b, char c ) {
+    b->cur[0] = c;
+    b->cur++;
+}
+
+static void bson_append( bson *b, const void *data, int len ) {
+    memcpy( b->cur , data , len );
+    b->cur += len;
+}
+
+static void bson_append32( bson *b, const void *data ) {
+    bson_little_endian32( b->cur, data );
+    b->cur += 4;
+}
+
+static void bson_append64( bson *b, const void *data ) {
+    bson_little_endian64( b->cur, data );
+    b->cur += 8;
+}
+
+int bson_ensure_space( bson *b, const int bytesNeeded ) {
+    int pos = b->cur - b->data;
+    char *orig = b->data;
+    int new_size;
+
+    if ( pos + bytesNeeded <= b->dataSize )
+        return BSON_OK;
+
+    new_size = 1.5 * ( b->dataSize + bytesNeeded );
+
+    if( new_size < b->dataSize ) {
+        if( ( b->dataSize + bytesNeeded ) < INT_MAX )
+            new_size = INT_MAX;
+        else {
+            b->err = BSON_SIZE_OVERFLOW;
+            return BSON_ERROR;
+        }
+    }
+
+    b->data = (char*)bson_realloc( b->data, new_size );
+    if ( !b->data )
+        bson_fatal_msg( !!b->data, "realloc() failed" );
+
+    b->dataSize = new_size;
+    b->cur += b->data - orig;
+
+    return BSON_OK;
+}
+
+int bson_finish( bson *b ) {
+    int i;
+
+    if( b->err & BSON_NOT_UTF8 )
+        return BSON_ERROR;
+
+    if ( ! b->finished ) {
+        if ( bson_ensure_space( b, 1 ) == BSON_ERROR ) return BSON_ERROR;
+        bson_append_byte( b, 0 );
+        i = b->cur - b->data;
+        bson_little_endian32( b->data, &i );
+        b->finished = 1;
+    }
+
+    return BSON_OK;
+}
+
+void bson_destroy( bson *b ) {
+    bson_free( b->data );
+    b->err = 0;
+    b->data = 0;
+    b->cur = 0;
+    b->finished = 1;
+}
+
+static int bson_append_estart( bson *b, int type, const char *name, const int dataSize ) {
+    const int len = strlen( name ) + 1;
+
+    if ( b->finished ) {
+        b->err |= BSON_ALREADY_FINISHED;
+        return BSON_ERROR;
+    }
+
+    if ( bson_ensure_space( b, 1 + len + dataSize ) == BSON_ERROR ) {
+        return BSON_ERROR;
+    }
+
+    if( bson_check_field_name( b, ( const char * )name, len - 1 ) == BSON_ERROR ) {
+        bson_builder_error( b );
+        return BSON_ERROR;
+    }
+
+    bson_append_byte( b, ( char )type );
+    bson_append( b, name, len );
+    return BSON_OK;
+}
+
+/* ----------------------------
+   BUILDING TYPES
+   ------------------------------ */
+
+int bson_append_int( bson *b, const char *name, const int i ) {
+    if ( bson_append_estart( b, BSON_INT, name, 4 ) == BSON_ERROR )
+        return BSON_ERROR;
+    bson_append32( b , &i );
+    return BSON_OK;
+}
+
+int bson_append_long( bson *b, const char *name, const int64_t i ) {
+    if ( bson_append_estart( b , BSON_LONG, name, 8 ) == BSON_ERROR )
+        return BSON_ERROR;
+    bson_append64( b , &i );
+    return BSON_OK;
+}
+
+int bson_append_double( bson *b, const char *name, const double d ) {
+    if ( bson_append_estart( b, BSON_DOUBLE, name, 8 ) == BSON_ERROR )
+        return BSON_ERROR;
+    bson_append64( b , &d );
+    return BSON_OK;
+}
+
+int bson_append_bool( bson *b, const char *name, const bson_bool_t i ) {
+    if ( bson_append_estart( b, BSON_BOOL, name, 1 ) == BSON_ERROR )
+        return BSON_ERROR;
+    bson_append_byte( b , i != 0 );
+    return BSON_OK;
+}
+
+int bson_append_null( bson *b, const char *name ) {
+    if ( bson_append_estart( b , BSON_NULL, name, 0 ) == BSON_ERROR )
+        return BSON_ERROR;
+    return BSON_OK;
+}
+
+int bson_append_undefined( bson *b, const char *name ) {
+    if ( bson_append_estart( b, BSON_UNDEFINED, name, 0 ) == BSON_ERROR )
+        return BSON_ERROR;
+    return BSON_OK;
+}
+
+static int bson_append_string_base( bson *b, const char *name,
+                             const char *value, int len, bson_type type ) {
+
+    int sl = len + 1;
+    if ( bson_check_string( b, ( const char * )value, sl - 1 ) == BSON_ERROR )
+        return BSON_ERROR;
+    if ( bson_append_estart( b, type, name, 4 + sl ) == BSON_ERROR ) {
+        return BSON_ERROR;
+    }
+    bson_append32( b , &sl );
+    bson_append( b , value , sl - 1 );
+    bson_append( b , "\0" , 1 );
+    return BSON_OK;
+}
+
+int bson_append_string( bson *b, const char *name, const char *value ) {
+    return bson_append_string_base( b, name, value, strlen ( value ), BSON_STRING );
+}
+
+int bson_append_symbol( bson *b, const char *name, const char *value ) {
+    return bson_append_string_base( b, name, value, strlen ( value ), BSON_SYMBOL );
+}
+
+int bson_append_code( bson *b, const char *name, const char *value ) {
+    return bson_append_string_base( b, name, value, strlen ( value ), BSON_CODE );
+}
+
+int bson_append_string_n( bson *b, const char *name, const char *value, int len ) {
+    return bson_append_string_base( b, name, value, len, BSON_STRING );
+}
+
+int bson_append_symbol_n( bson *b, const char *name, const char *value, int len ) {
+    return bson_append_string_base( b, name, value, len, BSON_SYMBOL );
+}
+
+int bson_append_code_n( bson *b, const char *name, const char *value, int len ) {
+    return bson_append_string_base( b, name, value, len, BSON_CODE );
+}
+
+int bson_append_code_w_scope_n( bson *b, const char *name,
+                                const char *code, int len, const bson *scope ) {
+
+    int sl = len + 1;
+    int size = 4 + 4 + sl + bson_size( scope );
+    if ( bson_append_estart( b, BSON_CODEWSCOPE, name, size ) == BSON_ERROR )
+        return BSON_ERROR;
+    bson_append32( b, &size );
+    bson_append32( b, &sl );
+    bson_append( b, code, sl );
+    bson_append( b, scope->data, bson_size( scope ) );
+    return BSON_OK;
+}
+
+int bson_append_code_w_scope( bson *b, const char *name, const char *code, const bson *scope ) {
+    return bson_append_code_w_scope_n( b, name, code, strlen ( code ), scope );
+}
+
+int bson_append_binary( bson *b, const char *name, char type, const char *str, int len ) {
+    if ( type == BSON_BIN_BINARY_OLD ) {
+        int subtwolen = len + 4;
+        if ( bson_append_estart( b, BSON_BINDATA, name, 4+1+4+len ) == BSON_ERROR )
+            return BSON_ERROR;
+        bson_append32( b, &subtwolen );
+        bson_append_byte( b, type );
+        bson_append32( b, &len );
+        bson_append( b, str, len );
+    } else {
+        if ( bson_append_estart( b, BSON_BINDATA, name, 4+1+len ) == BSON_ERROR )
+            return BSON_ERROR;
+        bson_append32( b, &len );
+        bson_append_byte( b, type );
+        bson_append( b, str, len );
+    }
+    return BSON_OK;
+}
+
+int bson_append_oid( bson *b, const char *name, const bson_oid_t *oid ) {
+    if ( bson_append_estart( b, BSON_OID, name, 12 ) == BSON_ERROR )
+        return BSON_ERROR;
+    bson_append( b , oid , 12 );
+    return BSON_OK;
+}
+
+int bson_append_new_oid( bson *b, const char *name ) {
+    bson_oid_t oid;
+    bson_oid_gen( &oid );
+    return bson_append_oid( b, name, &oid );
+}
+
+int bson_append_regex( bson *b, const char *name, const char *pattern, const char *opts ) {
+    const int plen = strlen( pattern )+1;
+    const int olen = strlen( opts )+1;
+    if ( bson_append_estart( b, BSON_REGEX, name, plen + olen ) == BSON_ERROR )
+        return BSON_ERROR;
+    if ( bson_check_string( b, pattern, plen - 1 ) == BSON_ERROR )
+        return BSON_ERROR;
+    bson_append( b , pattern , plen );
+    bson_append( b , opts , olen );
+    return BSON_OK;
+}
+
+int bson_append_bson( bson *b, const char *name, const bson *bson ) {
+    if ( bson_append_estart( b, BSON_OBJECT, name, bson_size( bson ) ) == BSON_ERROR )
+        return BSON_ERROR;
+    bson_append( b , bson->data , bson_size( bson ) );
+    return BSON_OK;
+}
+
+int bson_append_element( bson *b, const char *name_or_null, const bson_iterator *elem ) {
+    bson_iterator next = *elem;
+    int size;
+
+    bson_iterator_next( &next );
+    size = next.cur - elem->cur;
+
+    if ( name_or_null == NULL ) {
+        if( bson_ensure_space( b, size ) == BSON_ERROR )
+            return BSON_ERROR;
+        bson_append( b, elem->cur, size );
+    } else {
+        int data_size = size - 2 - strlen( bson_iterator_key( elem ) );
+        bson_append_estart( b, elem->cur[0], name_or_null, data_size );
+        bson_append( b, bson_iterator_value( elem ), data_size );
+    }
+
+    return BSON_OK;
+}
+
+int bson_append_timestamp( bson *b, const char *name, bson_timestamp_t *ts ) {
+    if ( bson_append_estart( b, BSON_TIMESTAMP, name, 8 ) == BSON_ERROR ) return BSON_ERROR;
+
+    bson_append32( b , &( ts->i ) );
+    bson_append32( b , &( ts->t ) );
+
+    return BSON_OK;
+}
+
+int bson_append_date( bson *b, const char *name, bson_date_t millis ) {
+    if ( bson_append_estart( b, BSON_DATE, name, 8 ) == BSON_ERROR ) return BSON_ERROR;
+    bson_append64( b , &millis );
+    return BSON_OK;
+}
+
+int bson_append_time_t( bson *b, const char *name, time_t secs ) {
+    return bson_append_date( b, name, ( bson_date_t )secs * 1000 );
+}
+
+int bson_append_start_object( bson *b, const char *name ) {
+    if ( bson_append_estart( b, BSON_OBJECT, name, 5 ) == BSON_ERROR ) return BSON_ERROR;
+    b->stack[ b->stackPos++ ] = b->cur - b->data;
+    bson_append32( b , &zero );
+    return BSON_OK;
+}
+
+int bson_append_start_array( bson *b, const char *name ) {
+    if ( bson_append_estart( b, BSON_ARRAY, name, 5 ) == BSON_ERROR ) return BSON_ERROR;
+    b->stack[ b->stackPos++ ] = b->cur - b->data;
+    bson_append32( b , &zero );
+    return BSON_OK;
+}
+
+int bson_append_finish_object( bson *b ) {
+    char *start;
+    int i;
+    if ( bson_ensure_space( b, 1 ) == BSON_ERROR ) return BSON_ERROR;
+    bson_append_byte( b , 0 );
+
+    start = b->data + b->stack[ --b->stackPos ];
+    i = b->cur - start;
+    bson_little_endian32( start, &i );
+
+    return BSON_OK;
+}
+
+int bson_append_finish_array( bson *b ) {
+    return bson_append_finish_object( b );
+}
+
+
+/* Error handling and allocators. */
+
+static bson_err_handler err_handler = NULL;
+
+bson_err_handler set_bson_err_handler( bson_err_handler func ) {
+    bson_err_handler old = err_handler;
+    err_handler = func;
+    return old;
+}
+
+void *bson_malloc( int size ) {
+    void *p;
+    p = bson_malloc_func( size );
+    bson_fatal_msg( !!p, "malloc() failed" );
+    return p;
+}
+
+void *bson_realloc( void *ptr, int size ) {
+    void *p;
+    p = bson_realloc_func( ptr, size );
+    bson_fatal_msg( !!p, "realloc() failed" );
+    return p;
+}
+
+int _bson_errprintf( const char *format, ... ) {
+    va_list ap;
+    int ret;
+    va_start( ap, format );
+    ret = vfprintf( stderr, format, ap );
+    va_end( ap );
+
+    return ret;
+}
+
+/**
+ * This method is invoked when a non-fatal bson error is encountered.
+ * Calls the error handler if available.
+ *
+ *  @param
+ */
+void bson_builder_error( bson *b ) {
+    if( err_handler )
+        err_handler( "BSON error." );
+}
+
+void bson_fatal( int ok ) {
+    bson_fatal_msg( ok, "" );
+}
+
+void bson_fatal_msg( int ok , const char *msg ) {
+    if ( ok )
+        return;
+
+    if ( err_handler ) {
+        err_handler( msg );
+    }
+
+    bson_errprintf( "error: %s\n" , msg );
+    exit( -5 );
+}
+
+
+/* Efficiently copy an integer to a string. */
+
+void bson_numstr( char *str, int i ) {
+    if( i < 1000 )
+        memcpy( str, bson_numstrs[i], 4 );
+    else
+        bson_sprintf( str,"%d", i );
+}
+
+/* encoding.c */
+
+/*
+ * Copyright 2009-2011 10gen, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Portions Copyright 2001 Unicode, Inc.
+ *
+ * Disclaimer
+ *
+ * This source code is provided as is by Unicode, Inc. No claims are
+ * made as to fitness for any particular purpose. No warranties of any
+ * kind are expressed or implied. The recipient agrees to determine
+ * applicability of information provided. If this file has been
+ * purchased on magnetic or optical media from Unicode, Inc., the
+ * sole remedy for any claim will be exchange of defective media
+ * within 90 days of receipt.
+ *
+ * Limitations on Rights to Redistribute This Code
+ *
+ * Unicode, Inc. hereby grants the right to freely use the information
+ * supplied in this file in the creation of products supporting the
+ * Unicode Standard, and to make copies of this file in any form
+ * for internal or external distribution as long as this notice
+ * remains attached.
+ */
+
+/*
+ * Index into the table below with the first byte of a UTF-8 sequence to
+ * get the number of trailing bytes that are supposed to follow it.
+ */
+static const char trailingBytesForUTF8[256] = {
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+    2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 3,3,3,3,3,3,3,3,4,4,4,4,5,5,5,5
+};
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * Utility routine to tell whether a sequence of bytes is legal UTF-8.
+ * This must be called with the length pre-determined by the first byte.
+ * The length can be set by:
+ *  length = trailingBytesForUTF8[*source]+1;
+ * and the sequence is illegal right away if there aren't that many bytes
+ * available.
+ * If presented with a length > 4, this returns 0.  The Unicode
+ * definition of UTF-8 goes up to 4-byte sequences.
+ */
+static int isLegalUTF8( const unsigned char *source, int length ) {
+    unsigned char a;
+    const unsigned char *srcptr = source + length;
+    switch ( length ) {
+    default:
+        return 0;
+        /* Everything else falls through when "true"... */
+    case 4:
+        if ( ( a = ( *--srcptr ) ) < 0x80 || a > 0xBF ) return 0;
+    case 3:
+        if ( ( a = ( *--srcptr ) ) < 0x80 || a > 0xBF ) return 0;
+    case 2:
+        if ( ( a = ( *--srcptr ) ) > 0xBF ) return 0;
+        switch ( *source ) {
+            /* no fall-through in this inner switch */
+        case 0xE0:
+            if ( a < 0xA0 ) return 0;
+            break;
+        case 0xF0:
+            if ( a < 0x90 ) return 0;
+            break;
+        case 0xF4:
+            if ( a > 0x8F ) return 0;
+            break;
+        default:
+            if ( a < 0x80 ) return 0;
+        }
+    case 1:
+        if ( *source >= 0x80 && *source < 0xC2 ) return 0;
+        if ( *source > 0xF4 ) return 0;
+    }
+    return 1;
+}
+
+static int bson_validate_string( bson *b, const unsigned char *string,
+                                 const int length, const char check_utf8, const char check_dot,
+                                 const char check_dollar ) {
+
+    int position = 0;
+    int sequence_length = 1;
+
+    if( check_dollar && string[0] == '$' ) {
+        b->err |= BSON_FIELD_INIT_DOLLAR;
+    }
+
+    while ( position < length ) {
+        if ( check_dot && *( string + position ) == '.' ) {
+            b->err |= BSON_FIELD_HAS_DOT;
+        }
+
+        if ( check_utf8 ) {
+            sequence_length = trailingBytesForUTF8[*( string + position )] + 1;
+            if ( ( position + sequence_length ) > length ) {
+                b->err |= BSON_NOT_UTF8;
+                return BSON_ERROR;
+            }
+            if ( !isLegalUTF8( string + position, sequence_length ) ) {
+                b->err |= BSON_NOT_UTF8;
+                return BSON_ERROR;
+            }
+        }
+        position += sequence_length;
+    }
+
+    return BSON_OK;
+}
+
+
+int bson_check_string( bson *b, const char *string,
+                       const int length ) {
+
+    return bson_validate_string( b, ( const unsigned char * )string, length, 1, 0, 0 );
+}
+
+int bson_check_field_name( bson *b, const char *string,
+                           const int length ) {
+
+    return bson_validate_string( b, ( const unsigned char * )string, length, 1, 1, 1 );
+}