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@keyurdg

keyurdg/bug67839.patch Secret

Created Aug 14, 2014
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diff --git a/ext/mysqli/tests/mysqli_float_handling.phpt b/ext/mysqli/tests/mysqli_float_handling.phpt
new file mode 100644
index 0000000..b2821a2
--- /dev/null
+++ b/ext/mysqli/tests/mysqli_float_handling.phpt
@@ -0,0 +1,58 @@
+--TEST--
+mysqli_float_handling - ensure 4 byte float is handled correctly
+--SKIPIF--
+<?php
+ require_once('skipif.inc');
+ require_once('skipifemb.inc');
+ require_once('skipifconnectfailure.inc');
+?>
+--FILE--
+<?php
+ require('connect.inc');
+ if (!$link = my_mysqli_connect($host, $user, $passwd, $db, $port, $socket)) {
+ printf("[001] [%d] %s\n", mysqli_connect_errno(), mysqli_connect_error());
+ die();
+ }
+
+
+ if (!mysqli_query($link, "DROP TABLE IF EXISTS test")) {
+ printf("[002] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
+ die();
+ }
+
+ if (!mysqli_query($link, "CREATE TABLE test(id INT PRIMARY KEY, fp4 FLOAT, fp8 DOUBLE) ENGINE = InnoDB")) {
+ printf("[003] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
+ die();
+ }
+
+ // Insert via string to make sure the real floating number gets to the DB
+ if (!mysqli_query($link, "INSERT INTO test(id, fp4, fp8) VALUES (1, 9.9999, 9.9999)")) {
+ printf("[004] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
+ die();
+ }
+
+ if (!($stmt = mysqli_prepare($link, "SELECT id, fp4, fp8 FROM test"))) {
+ printf("[005] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
+ die();
+ }
+
+ if (!mysqli_stmt_execute($stmt)) {
+ printf("[006] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
+ die();
+ }
+
+
+ if (!($result = mysqli_stmt_get_result($stmt))) {
+ printf("[007] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
+ die();
+ }
+
+ $data = mysqli_fetch_assoc($result);
+ print $data['id'] . ": " . $data['fp4'] . ": " . $data['fp8'] . "\n";
+?>
+--CLEAN--
+<?php
+ require_once("clean_table.inc");
+?>
+--EXPECTF--
+1: 9.9999: 9.9999
diff --git a/ext/mysqlnd/config9.m4 b/ext/mysqlnd/config9.m4
index 2c15c34..d730ba7 100644
--- a/ext/mysqlnd/config9.m4
+++ b/ext/mysqlnd/config9.m4
@@ -51,3 +51,29 @@ if test "$PHP_MYSQLND" != "no" || test "$PHP_MYSQLND_ENABLED" = "yes" || test "$
#endif
])
fi
+
+dnl
+dnl Check if the compiler supports Decimal32/64/128 types from the IEEE-754 2008 version
+dnl References: http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1657.pdf
+dnl http://speleotrove.com/decimal/
+dnl
+AC_CACHE_CHECK([whether whether compiler supports Decimal32/64/128 types], ac_cv_decimal_fp_supported,[
+AC_TRY_RUN( [
+#include <stdio.h>
+
+int main(int argc, char **argv) {
+ typedef float dec32 __attribute__((mode(SD)));
+ dec32 k = 99.49f;
+ double d2 = (double)k;
+ return 0;
+}
+],[
+ ac_cv_decimal_fp_supported=yes
+],[
+ ac_cv_decimal_fp_supported=no
+],[
+ ac_cv_decimal_fp_supported=no
+])])
+if test "$ac_cv_decimal_fp_supported" = "yes"; then
+ AC_DEFINE(HAVE_DECIMAL_FP_SUPPORT, 1, [Define if the compiler supports Decimal32/64/128 types.])
+fi
diff --git a/ext/mysqlnd/mysqlnd_ps_codec.c b/ext/mysqlnd/mysqlnd_ps_codec.c
index e2640c7..3f7d310 100644
--- a/ext/mysqlnd/mysqlnd_ps_codec.c
+++ b/ext/mysqlnd/mysqlnd_ps_codec.c
@@ -195,12 +195,53 @@ void ps_fetch_float(zval *zv, const MYSQLND_FIELD * const field,
unsigned int pack_len, zend_uchar **row,
zend_bool as_unicode TSRMLS_DC)
{
- float value;
+ float fval;
+ double dval;
DBG_ENTER("ps_fetch_float");
- float4get(value, *row);
- ZVAL_DOUBLE(zv, value);
+ float4get(fval, *row);
(*row)+= 4;
- DBG_INF_FMT("value=%f", value);
+ DBG_INF_FMT("value=%f", fval);
+
+ /*
+ * The following is needed to correctly support 4-byte floats.
+ * Otherwise, a value of 9.99 in a FLOAT column comes out of mysqli
+ * as 9.9998998641968.
+ *
+ * For GCC, we use the built-in decimal support to "up-convert" a
+ * 4-byte float to a 8-byte double.
+ * When that is not available, we fall back to converting the float
+ * to a string and then converting the string to a double. This mimics
+ * what MySQL does.
+ */
+#ifdef HAVE_DECIMAL_FP_SUPPORT
+ {
+ typedef float dec32 __attribute__((mode(SD)));
+ dec32 d32val = fval;
+
+ /* The following cast is guaranteed to do the right thing */
+ dval = (double) d32val;
+ }
+#else
+ {
+ char num_buf[2048]; /* Over allocated */
+ char *s;
+
+ /* Convert to string. Ignoring localization, etc.
+ * Following MySQL's rules. If precision is undefined (NOT_FIXED_DEC i.e. 31)
+ * or larger than 31, the value is limited to 6 (FLT_DIG).
+ */
+ s = php_gcvt(fval,
+ field->decimals >= 31 ? 6 : field->decimals,
+ '.',
+ 'e',
+ num_buf);
+
+ /* And now convert back to double */
+ dval = zend_strtod(s, NULL);
+ }
+#endif
+
+ ZVAL_DOUBLE(zv, dval);
DBG_VOID_RETURN;
}
/* }}} */
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