Initial patch for 0 mode float conversion. The magic number is better to be improved. Any suggestion where to define it?

Author: yohgaki

ext/json/json_encoder.c

@@ -104,7 +104,11 @@ static inline void php_json_encode_double(smart_str *buf, double d, int options)
 {
 	size_t len;
 	char num[PHP_JSON_DOUBLE_MAX_LENGTH];
-	php_gcvt(d, (int)EG(precision), '.', 'e', &num[0]);
+	if (PG(serialize_precision) == -1) {
+		php_0cvt(d, 17, '.', 'e', num);
+	} else {
+		php_gcvt(d, PG(serialize_precision), '.', 'e', num);
+	}
 	len = strlen(num);
 	if (options & PHP_JSON_PRESERVE_ZERO_FRACTION && strchr(num, '.') == NULL && len < PHP_JSON_DOUBLE_MAX_LENGTH - 2) {
 		num[len++] = '.';

ext/standard/var.c

@@ -436,8 +436,7 @@ static void php_object_element_export(zval *zv, zend_ulong index, zend_string *k
 PHPAPI void php_var_export_ex(zval *struc, int level, smart_str *buf) /* {{{ */
 {
 	HashTable *myht;
-	char *tmp_str;
-	size_t tmp_len;
+	char tmp_str[2048]; /* Use the same magic number of spprintf.c NUM_BUF_SIZE */
 	zend_string *ztmp, *ztmp2;
 	zend_ulong index;
 	zend_string *key;
@@ -458,18 +457,26 @@ PHPAPI void php_var_export_ex(zval *struc, int level, smart_str *buf) /* {{{ */
 			smart_str_append_long(buf, Z_LVAL_P(struc));
 			break;
 		case IS_DOUBLE:
+			/* TODO: check INF, -INF and NAN in the new logic
 			tmp_len = spprintf(&tmp_str, 0,"%.*H", PG(serialize_precision), Z_DVAL_P(struc));
 			smart_str_appendl(buf, tmp_str, tmp_len);
-			/* Without a decimal point, PHP treats a number literal as an int.
+			 * Without a decimal point, PHP treats a number literal as an int.
 			 * This check even works for scientific notation, because the
 			 * mantissa always contains a decimal point.
 			 * We need to check for finiteness, because INF, -INF and NAN
 			 * must not have a decimal point added.
-			 */
+			 *
 			if (zend_finite(Z_DVAL_P(struc)) && NULL == strchr(tmp_str, '.')) {
 				smart_str_appendl(buf, ".0", 2);
 			}
 			efree(tmp_str);
+			*/
+			if (PG(serialize_precision < 0)) {
+				php_0cvt(Z_DVAL_P(struc), 17, '.', 'E', tmp_str);
+			} else {
+				php_gcvt(Z_DVAL_P(struc), (int)PG(serialize_precision), '.', 'E', tmp_str);
+			}
+			smart_str_appends(buf, tmp_str);
 			break;
 		case IS_STRING:
 			ztmp = php_addcslashes(Z_STR_P(struc), 0, "'\\", 2);
@@ -844,16 +851,17 @@ static void php_var_serialize_intern(smart_str *buf, zval *struc, php_serialize_
 			return;
 
 		case IS_DOUBLE: {
-				char *s;
-
-				smart_str_appendl(buf, "d:", 2);
-				s = (char *) safe_emalloc(PG(serialize_precision), 1, MAX_LENGTH_OF_DOUBLE + 1);
-				php_gcvt(Z_DVAL_P(struc), (int)PG(serialize_precision), '.', 'E', s);
-				smart_str_appends(buf, s);
-				smart_str_appendc(buf, ';');
-				efree(s);
-				return;
+			char tmp_str[2048]; /* Use the same magic number of spprintf.c NUM_BUF_SIZE */
+			smart_str_appendl(buf, "d:", 2);
+			if (PG(serialize_precision < 0)) {
+				php_0cvt(Z_DVAL_P(struc), 17, '.', 'E', tmp_str);
+			} else {
+				php_gcvt(Z_DVAL_P(struc), (int)PG(serialize_precision), '.', 'E', tmp_str);
 			}
+			smart_str_appends(buf, tmp_str);
+			smart_str_appendc(buf, ';');
+			return;
+		}
 
 		case IS_STRING:
 			php_var_serialize_string(buf, Z_STRVAL_P(struc), Z_STRLEN_P(struc));

main/main.c

@@ -140,6 +140,23 @@ static PHP_INI_MH(OnSetPrecision)
 }
 /* }}} */
 
+/* {{{ PHP_INI_MH
+ */
+static PHP_INI_MH(OnSetSerializePrecision)
+{
+	zend_long i;
+
+	ZEND_ATOL(i, ZSTR_VAL(new_value));
+	if (i >= -1) {
+		PG(serialize_precision) = i;
+		return SUCCESS;
+	} else {
+		return FAILURE;
+	}
+}
+/* }}} */
+
+
 /* {{{ PHP_INI_MH
  */
 static PHP_INI_MH(OnChangeMemoryLimit)
@@ -533,7 +550,7 @@ PHP_INI_BEGIN()
 	STD_PHP_INI_BOOLEAN("track_errors",			"0",		PHP_INI_ALL,		OnUpdateBool,			track_errors,			php_core_globals,	core_globals)
 
 	STD_PHP_INI_ENTRY("unserialize_callback_func",	NULL,	PHP_INI_ALL,		OnUpdateString,			unserialize_callback_func,	php_core_globals,	core_globals)
-	STD_PHP_INI_ENTRY("serialize_precision",	"17",	PHP_INI_ALL,		OnUpdateLongGEZero,			serialize_precision,	php_core_globals,	core_globals)
+	STD_PHP_INI_ENTRY("serialize_precision",	"-1",	PHP_INI_ALL,		OnSetSerializePrecision,			serialize_precision,	php_core_globals,	core_globals)
 	STD_PHP_INI_ENTRY("arg_separator.output",	"&",		PHP_INI_ALL,		OnUpdateStringUnempty,	arg_separator.output,	php_core_globals,	core_globals)
 	STD_PHP_INI_ENTRY("arg_separator.input",	"&",		PHP_INI_SYSTEM|PHP_INI_PERDIR,	OnUpdateStringUnempty,	arg_separator.input,	php_core_globals,	core_globals)
 

main/snprintf.c

@@ -139,12 +139,12 @@ static inline char *php_fcvt(double value, int ndigit, int *decpt, int *sign) /*
 }
 /* }}} */
 
-PHPAPI char *php_gcvt(double value, int ndigit, char dec_point, char exponent, char *buf) /* {{{ */
+static inline char *_php_cvt(double value, int ndigit, char dec_point, char exponent, char *buf, int mode) /* {{{ */
 {
 	char *digits, *dst, *src;
 	int i, decpt, sign;
 
-	digits = zend_dtoa(value, 2, ndigit, &decpt, &sign, NULL);
+	digits = zend_dtoa(value, mode, ndigit, &decpt, &sign, NULL);
 	if (decpt == 9999) {
 		/*
 		 * Infinity or NaN, convert to inf or nan with sign.
@@ -234,6 +234,20 @@ PHPAPI char *php_gcvt(double value, int ndigit, char dec_point, char exponent, c
 }
 /* }}} */
 
+PHPAPI char *php_gcvt(double value, int ndigit, char dec_point, char exponent, char *buf) /* {{{ */
+{
+	return _php_cvt(value, ndigit, dec_point, exponent, buf, 2);
+}
+/* }}} */
+
+PHPAPI char *php_0cvt(double value, int ndigit, char dec_point, char exponent, char *buf) /* {{{ */
+{
+	return _php_cvt(value, ndigit, dec_point, exponent, buf, 0);
+}
+/* }}} */
+
+
+
 /* {{{ Apache license */
 /* ====================================================================
  * Copyright (c) 1995-1998 The Apache Group.  All rights reserved.

main/snprintf.h

@@ -86,6 +86,7 @@ PHPAPI int ap_php_vasprintf(char **buf, const char *format, va_list ap);
 PHPAPI int ap_php_asprintf(char **buf, const char *format, ...) ZEND_ATTRIBUTE_FORMAT(printf, 2, 3);
 PHPAPI int php_sprintf (char* s, const char* format, ...) PHP_ATTRIBUTE_FORMAT(printf, 2, 3);
 PHPAPI char * php_gcvt(double value, int ndigit, char dec_point, char exponent, char *buf);
+PHPAPI char * php_0cvt(double value, int ndigit, char dec_point, char exponent, char *buf);
 PHPAPI char * php_conv_fp(char format, double num,
 		 boolean_e add_dp, int precision, char dec_point, bool_int * is_negative, char *buf, size_t *len);