Feature request 415 for sqlsrv (#861)

source/shared/core_sqlsrv.h

@@ -1107,6 +1107,7 @@ enum SQLSRV_STMT_OPTIONS {
    SQLSRV_STMT_OPTION_SCROLLABLE,
    SQLSRV_STMT_OPTION_CLIENT_BUFFER_MAX_SIZE,
    SQLSRV_STMT_OPTION_DATE_AS_STRING,
+   SQLSRV_STMT_OPTION_FORMAT_DECIMALS,
 
    // Driver specific connection options
    SQLSRV_STMT_OPTION_DRIVER_SPECIFIC = 1000,
@@ -1296,6 +1297,11 @@ struct stmt_option_date_as_string : public stmt_option_functor {
     virtual void operator()( _Inout_ sqlsrv_stmt* stmt, stmt_option const* opt, _In_ zval* value_z TSRMLS_DC );
 };
 
+struct stmt_option_format_decimals : public stmt_option_functor {
+
+    virtual void operator()( _Inout_ sqlsrv_stmt* stmt, stmt_option const* opt, _In_ zval* value_z TSRMLS_DC );
+};
+
 // used to hold the table for statment options
 struct stmt_option {
 
@@ -1334,16 +1340,39 @@ extern php_stream_wrapper g_sqlsrv_stream_wrapper;
 #define SQLSRV_STREAM_WRAPPER "sqlsrv"
 #define SQLSRV_STREAM         "sqlsrv_stream"
 
+// *** parameter metadata struct ***
+struct param_meta_data
+{
+    SQLSMALLINT sql_type; 
+    SQLSMALLINT decimal_digits;
+    SQLSMALLINT nullable; 
+    SQLULEN     column_size;
+
+    param_meta_data() : sql_type(0), decimal_digits(0), column_size(0), nullable(0)
+    {
+    }
+
+    ~param_meta_data()
+    {
+    }
+
+    SQLSMALLINT get_sql_type() { return sql_type; }
+    SQLSMALLINT get_decimal_digits() { return decimal_digits; }
+    SQLSMALLINT get_nullable() { return nullable; }
+    SQLULEN get_column_size() { return column_size; }
+};
+
 // holds the output parameter information.  Strings also need the encoding and other information for
 // after processing.  Only integer, float, and strings are allowable output parameters.
 struct sqlsrv_output_param {
 
     zval* param_z;
     SQLSRV_ENCODING encoding;
-    SQLUSMALLINT param_num;         // used to index into the ind_or_len of the statement
-    SQLLEN original_buffer_len;     // used to make sure the returned length didn't overflow the buffer
-    SQLSRV_PHPTYPE php_out_type;    // used to convert output param if necessary
+    SQLUSMALLINT param_num;             // used to index into the ind_or_len of the statement
+    SQLLEN original_buffer_len;         // used to make sure the returned length didn't overflow the buffer
+    SQLSRV_PHPTYPE php_out_type;        // used to convert output param if necessary
     bool is_bool;
+    param_meta_data meta_data;      // parameter meta data
 
     // string output param constructor
     sqlsrv_output_param( _In_ zval* p_z, _In_ SQLSRV_ENCODING enc, _In_ int num, _In_ SQLUINTEGER buffer_len ) :
@@ -1361,34 +1390,31 @@ struct sqlsrv_output_param {
         php_out_type(php_out_type)
     {
     }
-};
 
-// forward decls
-struct sqlsrv_result_set;
-struct field_meta_data;
-
-// *** parameter metadata struct ***
-struct param_meta_data
-{
-    SQLSMALLINT sql_type; 
-    SQLSMALLINT decimal_digits;
-    SQLSMALLINT nullable; 
-    SQLULEN     column_size;
-
-    param_meta_data() : sql_type(0), decimal_digits(0), column_size(0), nullable(0)
-    {
+    void saveMetaData(SQLSMALLINT sql_type, SQLSMALLINT column_size, SQLSMALLINT decimal_digits, SQLSMALLINT nullable = SQL_NULLABLE) 
+    {   
+        meta_data.sql_type = sql_type;
+        meta_data.column_size = column_size;
+        meta_data.decimal_digits = decimal_digits;
+        meta_data.nullable = nullable;
     }
 
-    ~param_meta_data()
-    {
+    SQLSMALLINT getDecimalDigits() 
+    {  
+        // Return decimal_digits only for decimal / numeric types. Otherwise, return -1
+        if (meta_data.sql_type == SQL_DECIMAL || meta_data.sql_type == SQL_NUMERIC) {
+            return meta_data.decimal_digits;
+        }
+        else {
+            return -1;
+        }
     }
-
-    SQLSMALLINT get_sql_type() { return sql_type; }
-    SQLSMALLINT get_decimal_digits() { return decimal_digits; }
-    SQLSMALLINT get_nullable() { return nullable; }
-    SQLULEN get_column_size() { return column_size; }
 };
 
+// forward decls
+struct sqlsrv_result_set;
+struct field_meta_data;
+
 // *** Statement resource structure *** 
 struct sqlsrv_stmt : public sqlsrv_context {
 
@@ -1409,6 +1435,7 @@ struct sqlsrv_stmt : public sqlsrv_context {
     unsigned long query_timeout;          // maximum allowed statement execution time
     zend_long buffered_query_limit;       // maximum allowed memory for a buffered query (measured in KB)
     bool date_as_string;                  // false by default but the user can set this to true to retrieve datetime values as strings
+    short num_decimals;                   // indicates number of decimals shown in fetched results (-1 by default, which means no formatting required)
 
     // holds output pointers for SQLBindParameter
     // We use a deque because it 1) provides the at/[] access in constant time, and 2) grows dynamically without moving
@@ -1743,6 +1770,8 @@ enum SQLSRV_ERROR_CODES {
     SQLSRV_ERROR_DOUBLE_CONVERSION_FAILED,
     SQLSRV_ERROR_INVALID_OPTION_WITH_ACCESS_TOKEN,
     SQLSRV_ERROR_EMPTY_ACCESS_TOKEN,
+    SQLSRV_ERROR_INVALID_FORMAT_DECIMALS,
+    SQLSRV_ERROR_FORMAT_DECIMALS_OUT_OF_RANGE,
 
     // Driver specific error codes starts from here.
     SQLSRV_ERROR_DRIVER_SPECIFIC = 1000,

source/shared/core_stmt.cpp

@@ -107,6 +107,7 @@ void default_sql_type( _Inout_ sqlsrv_stmt* stmt, _In_opt_ SQLULEN paramno, _In_
                        _Out_ SQLSMALLINT& sql_type TSRMLS_DC );
 void col_cache_dtor( _Inout_ zval* data_z );
 void field_cache_dtor( _Inout_ zval* data_z );
+void format_decimal_numbers(_In_ SQLSMALLINT decimals_digits, _In_ SQLSMALLINT field_scale, _Inout_updates_bytes_(*field_len) char*& field_value, _Inout_ SQLLEN* field_len);
 void finalize_output_parameters( _Inout_ sqlsrv_stmt* stmt TSRMLS_DC );
 void get_field_as_string( _Inout_ sqlsrv_stmt* stmt, _In_ SQLUSMALLINT field_index, _Inout_ sqlsrv_phptype sqlsrv_php_type,
 						  _Inout_updates_bytes_(*field_len) void*& field_value, _Inout_ SQLLEN* field_len TSRMLS_DC );
@@ -141,8 +142,9 @@ sqlsrv_stmt::sqlsrv_stmt( _In_ sqlsrv_conn* c, _In_ SQLHANDLE handle, _In_ error
     past_next_result_end( false ),
     query_timeout( QUERY_TIMEOUT_INVALID ),
     date_as_string(false),
+    num_decimals(-1),           // -1 means no formatting required
     buffered_query_limit( sqlsrv_buffered_result_set::BUFFERED_QUERY_LIMIT_INVALID ),
-    param_ind_ptrs( 10 ),    // initially hold 10 elements, which should cover 90% of the cases and only take < 100 byte
+    param_ind_ptrs( 10 ),       // initially hold 10 elements, which should cover 90% of the cases and only take < 100 byte
     send_streams_at_exec( true ),
     current_stream( NULL, SQLSRV_ENCODING_DEFAULT ),
     current_stream_read( 0 )
@@ -571,6 +573,8 @@ void core_sqlsrv_bind_param( _Inout_ sqlsrv_stmt* stmt, _In_ SQLUSMALLINT param_
                     // save the parameter to be adjusted and/or converted after the results are processed
                     sqlsrv_output_param output_param( param_ref, encoding, param_num, static_cast<SQLUINTEGER>( buffer_len ) );
 
+                    output_param.saveMetaData(sql_type, column_size, decimal_digits);
+
                     save_output_param_for_later( stmt, output_param TSRMLS_CC );
 
                     // For output parameters, if we set the column_size to be same as the buffer_len,
@@ -1416,6 +1420,21 @@ void stmt_option_date_as_string:: operator()( _Inout_ sqlsrv_stmt* stmt, stmt_op
     }
 }
 
+void stmt_option_format_decimals:: operator()( _Inout_ sqlsrv_stmt* stmt, stmt_option const* /**/, _In_ zval* value_z TSRMLS_DC )
+{
+    // first check if the input is an integer
+    CHECK_CUSTOM_ERROR(Z_TYPE_P(value_z) != IS_LONG, stmt, SQLSRV_ERROR_INVALID_FORMAT_DECIMALS) {
+        throw core::CoreException();
+    }
+
+    zend_long format_decimals = Z_LVAL_P(value_z);
+    CHECK_CUSTOM_ERROR(format_decimals  < 0 || format_decimals  > SQL_SERVER_MAX_PRECISION, stmt, SQLSRV_ERROR_FORMAT_DECIMALS_OUT_OF_RANGE, format_decimals) {
+        throw core::CoreException();
+    }
+
+    stmt->num_decimals = static_cast<short>(format_decimals);
+}
+
 // internal function to release the active stream.  Called by each main API function
 // that will alter the statement and cancel any retrieval of data from a stream.
 void close_active_stream( _Inout_ sqlsrv_stmt* stmt TSRMLS_DC )
@@ -2079,6 +2098,130 @@ void field_cache_dtor( _Inout_ zval* data_z )
 	sqlsrv_free( cache );
 }
 
+// To be called for formatting decimal / numeric fetched values from finalize_output_parameters() and/or get_field_as_string()
+void format_decimal_numbers(_In_ SQLSMALLINT decimals_digits, _In_ SQLSMALLINT field_scale, _Inout_updates_bytes_(*field_len) char*& field_value, _Inout_ SQLLEN* field_len)
+{
+    // In SQL Server, the default maximum precision of numeric and decimal data types is 38
+    //
+    // Note: stmt->num_decimals is -1 by default, which means no formatting on decimals / numerics is necessary
+    // If the required number of decimals is larger than the field scale, will use the column field scale instead.
+    // This is to ensure the number of decimals adheres to the column field scale. If smaller, the output value may be rounded up.
+    //
+    // Note: it's possible that the decimal / numeric value does not contain a decimal dot because the field scale is 0.
+    // Thus, first check if the decimal dot exists. If not, no formatting necessary, regardless of decimals_digits
+    //
+    std::string str = field_value;
+    size_t pos = str.find_first_of('.');
+
+    if (pos == std::string::npos || decimals_digits < 0) {
+        return;
+    }
+
+    SQLSMALLINT num_decimals = decimals_digits;
+    if (num_decimals > field_scale) {
+        num_decimals = field_scale;
+    }
+
+    // We want the rounding to be consistent with php number_format(), http://php.net/manual/en/function.number-format.php
+    // as well as SQL Server Management studio, such that the least significant digit will be rounded up if it is 
+    // followed by 5 or above. 
+
+    bool isNegative = false;
+
+    // If negative, remove the minus sign for now so as not to complicate the rounding process
+    if (str[0] == '-') {
+        isNegative = true;
+        std::ostringstream oss;
+        oss << str.substr(1);
+        str = oss.str();
+        pos = str.find_first_of('.');
+    }
+
+    // Adds the leading zero if not exists
+    if (pos == 0) {
+        std::ostringstream oss;
+        oss << '0' << str;
+        str = oss.str();
+        pos++;
+    }
+
+    size_t last = 0;
+    if (num_decimals == 0) {
+        // Chop all decimal digits, including the decimal dot
+        size_t pos2 = pos + 1;
+        short n = str[pos2] - '0';
+        if (n >= 5) {
+            // Start rounding up - starting from the digit left of the dot all the way to the first digit
+            bool carry_over = true;
+            for (short p = pos - 1; p >= 0 && carry_over; p--) {
+                n = str[p] - '0';
+                if (n == 9) {
+                    str[p] = '0' ;
+                    carry_over = true;
+                }
+                else {
+                    n++;
+                    carry_over = false;
+                    str[p] = '0' + n;
+                }
+            }
+            if (carry_over) {
+                std::ostringstream oss;
+                oss << '1' << str.substr(0, pos);
+                str = oss.str();
+                pos++;
+            }
+        }
+        last = pos;
+    }
+    else {
+        size_t pos2 = pos + num_decimals + 1;
+        // No need to check if rounding is necessary when pos2 has passed the last digit in the input string
+        if (pos2 < str.length()) {
+            short n = str[pos2] - '0';
+            if (n >= 5) {
+                // Start rounding up - starting from the digit left of pos2 all the way to the first digit
+                bool carry_over = true;
+                for (short p = pos2 - 1; p >= 0 && carry_over; p--) {
+                    if (str[p] == '.') { // Skip the dot
+                        continue;
+                    }
+                    n = str[p] - '0';
+                    if (n == 9) {
+                        str[p] = '0' ;
+                        carry_over = true;
+                    }
+                    else {
+                        n++;
+                        carry_over = false;
+                        str[p] = '0' + n;
+                    }
+                }
+                if (carry_over) {
+                    std::ostringstream oss;
+                    oss << '1' << str.substr(0, pos2);
+                    str = oss.str();
+                    pos2++;
+                }
+            }
+        }
+        last = pos2;
+    }
+
+    // Add the minus sign back if negative
+    if (isNegative) {
+        std::ostringstream oss;
+        oss << '-' << str.substr(0, last);
+        str = oss.str();
+    } else {
+        str = str.substr(0, last);
+    }
+
+    size_t len = str.length();
+    str.copy(field_value, len);
+    field_value[len] = '\0';
+    *field_len = len;
+}
 
 // To be called after all results are processed.  ODBC and SQL Server do not guarantee that all output
 // parameters will be present until all results are processed (since output parameters can depend on results
@@ -2160,6 +2303,11 @@ void finalize_output_parameters( _Inout_ sqlsrv_stmt* stmt TSRMLS_DC )
                 core::sqlsrv_zval_stringl(value_z, str, str_len);
             }
             else {
+                SQLSMALLINT decimal_digits = output_param->getDecimalDigits();
+                if (stmt->num_decimals >= 0 && decimal_digits >= 0) {
+                    format_decimal_numbers(stmt->num_decimals, decimal_digits, str, &str_len);
+                }
+
                 core::sqlsrv_zval_stringl(value_z, str, str_len);
             }
         }
@@ -2214,7 +2362,7 @@ void get_field_as_string( _Inout_ sqlsrv_stmt* stmt, _In_ SQLUSMALLINT field_ind
 {
     SQLRETURN r;
     SQLSMALLINT c_type;
-    SQLLEN sql_field_type = 0;
+    SQLSMALLINT sql_field_type = 0;
     SQLSMALLINT extra = 0;
     SQLLEN field_len_temp = 0;
     SQLLEN sql_display_size = 0;
@@ -2425,6 +2573,10 @@ void get_field_as_string( _Inout_ sqlsrv_stmt* stmt, _In_ SQLUSMALLINT field_ind
                     throw core::CoreException();
                 }
             }
+
+            if (stmt->num_decimals >= 0 && (sql_field_type == SQL_DECIMAL || sql_field_type == SQL_NUMERIC)) {
+                format_decimal_numbers(stmt->num_decimals, stmt->current_meta_data[field_index]->field_scale, field_value_temp, &field_len_temp);
+            }
         } // else if( sql_display_size >= 1 && sql_display_size <= SQL_SERVER_MAX_FIELD_SIZE )
 
         else {

source/sqlsrv/conn.cpp

@@ -174,6 +174,7 @@ namespace SSStmtOptionNames {
     const char SCROLLABLE[] = "Scrollable";
     const char CLIENT_BUFFER_MAX_SIZE[] = INI_BUFFERED_QUERY_LIMIT;
     const char DATE_AS_STRING[] = "ReturnDatesAsStrings";
+    const char FORMAT_DECIMALS[] = "FormatDecimals";
 }
 
 namespace SSConnOptionNames {
@@ -250,6 +251,12 @@ const stmt_option SS_STMT_OPTS[] = {
         SQLSRV_STMT_OPTION_DATE_AS_STRING, 
         std::unique_ptr<stmt_option_date_as_string>( new stmt_option_date_as_string )
     },
+    {
+        SSStmtOptionNames::FORMAT_DECIMALS, 
+        sizeof( SSStmtOptionNames::FORMAT_DECIMALS ),
+        SQLSRV_STMT_OPTION_FORMAT_DECIMALS, 
+        std::unique_ptr<stmt_option_format_decimals>( new stmt_option_format_decimals )
+    },
     { NULL, 0, SQLSRV_STMT_OPTION_INVALID, std::unique_ptr<stmt_option_functor>{} },
 };
 

source/sqlsrv/util.cpp

@@ -428,6 +428,14 @@ ss_error SS_ERRORS[] = {
         SQLSRV_ERROR_EMPTY_ACCESS_TOKEN,
         { IMSSP, (SQLCHAR*) "The Azure AD Access Token is empty. Expected a byte string.", -116, false}
     },
+    {
+        SQLSRV_ERROR_INVALID_FORMAT_DECIMALS,
+        { IMSSP, (SQLCHAR*) "Expected an integer to specify number of decimals to format the output values of decimal data types.", -117, false}
+    },
+    {
+        SQLSRV_ERROR_FORMAT_DECIMALS_OUT_OF_RANGE,
+        { IMSSP, (SQLCHAR*) "For formatting decimal data values, %1!d! is out of range. Expected an integer from 0 to 38, inclusive.", -118, true}
+    },
 
     // terminate the list of errors/warnings
     { UINT_MAX, {} }