From: YongHao Hu <christopherwuy@gmail.com>
Subject: msvcrt: Fix inconsistent rounding behaviour for sprintf and add tests.
Message-Id: <54C624FD.4050109@gmail.com>
Date: Mon, 26 Jan 2015 19:29:01 +0800

Fix bug https://bugs.winehq.org/show_bug.cgi?id=37913 .

---
  dlls/msvcrt/printf.h       |  7 ++++++-
  dlls/msvcrt/tests/printf.c | 25 +++++++++++++++++++++++++
  2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/dlls/msvcrt/printf.h b/dlls/msvcrt/printf.h
index 80133d6..d0815a9 100644
--- a/dlls/msvcrt/printf.h
+++ b/dlls/msvcrt/printf.h
@@ -338,7 +338,7 @@ int FUNC_NAME(pf_printf)(FUNC_NAME(puts_clbk) pf_puts, void *puts_ctx, const API
     MSVCRT_pthreadlocinfo locinfo;
     const APICHAR *q, *p = fmt;
     APICHAR buf[32];
-    int written = 0, pos, i;
+    int written = 0, pos, i, temp;
     FUNC_NAME(pf_flags) flags;
 
     TRACE("Format is: %s\n", FUNC_NAME(debugstr)(fmt));
@@ -584,6 +584,11 @@ int FUNC_NAME(pf_printf)(FUNC_NAME(puts_clbk) pf_puts, void *puts_ctx, const API
                 val = -val;
             }
 
+            if(flags.Precision >= 0 && toupper(flags.Format)!='G') {
+                temp = pow(10, flags.Precision);
+                val  = round(val * temp) / temp;
+            }
+
             sprintf(tmp, float_fmt, val);
             if(toupper(flags.Format)=='E' || toupper(flags.Format)=='G')
                 FUNC_NAME(pf_fixup_exponent)(tmp);
diff --git a/dlls/msvcrt/tests/printf.c b/dlls/msvcrt/tests/printf.c
index 0606c25..2688383 100644
--- a/dlls/msvcrt/tests/printf.c
+++ b/dlls/msvcrt/tests/printf.c
@@ -547,6 +547,31 @@ static void test_sprintf( void )
     ok(!strcmp(buffer,"1"), "failed\n");
     ok( r==1, "return count wrong\n");
 
+    format = "%.1f";
+    r = sprintf(buffer, format,-3.25);
+    ok(!strcmp(buffer,"-3.3"), "failed\n");
+    ok( r==4, "return count wrong\n");
+
+    format = "%.0f";
+    r = sprintf(buffer, format,0.5);
+    ok(!strcmp(buffer,"1"), "failed\n");
+    ok( r==1, "return count wrong\n");
+
+    format = "%.0f";
+    r = sprintf(buffer, format,1.5);
+    ok(!strcmp(buffer,"2"), "failed\n");
+    ok( r==1, "return count wrong\n");
+
+    format = "%.0f";
+    r = sprintf(buffer, format,2.5);
+    ok(!strcmp(buffer,"3"), "failed\n");
+    ok( r==1, "return count wrong\n");
+
+    format = "%.6g";
+    r = sprintf(buffer, format,1.0e-9);
+    ok(!strcmp(buffer,"1e-009"), "failed\n");
+    ok( r==6, "return count wrong\n");
+
     format = "%2.4e";
     r = sprintf(buffer, format,8.6);
     ok(!strcmp(buffer,"8.6000e+000"), "failed\n");