Iván Matellanes : msvcirt: Don' t return negative values in in_avail and out_waiting.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 611b7273863222e7636c5710ece60f12bd196d1d
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=611b7273863222e7636c5710ec...

Author: Iván Matellanes <matellanesivan(a)gmail.com>
Date:   Wed Oct 19 14:00:51 2016 +0200

msvcirt: Don't return negative values in in_avail and out_waiting.

Signed-off-by: Iván Matellanes <matellanesivan(a)gmail.com>
Signed-off-by: Piotr Caban <piotr(a)codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard(a)winehq.org>

---

 dlls/msvcirt/msvcirt.c       |  4 ++--
 dlls/msvcirt/tests/msvcirt.c | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/dlls/msvcirt/msvcirt.c b/dlls/msvcirt/msvcirt.c
index 8dfe988..e9103a9 100644
--- a/dlls/msvcirt/msvcirt.c
+++ b/dlls/msvcirt/msvcirt.c
@@ -556,7 +556,7 @@ DEFINE_THISCALL_WRAPPER(streambuf_in_avail, 4)
 int __thiscall streambuf_in_avail(const streambuf *this)
 {
     TRACE("(%p)\n", this);
-    return this->egptr - this->gptr;
+    return (this->egptr - this->gptr > 0) ? this->egptr - this->gptr : 0;
 }
 
 /* ?out_waiting(a)streambuf@@QBEHXZ */
@@ -565,7 +565,7 @@ DEFINE_THISCALL_WRAPPER(streambuf_out_waiting, 4)
 int __thiscall streambuf_out_waiting(const streambuf *this)
 {
     TRACE("(%p)\n", this);
-    return this->pptr - this->pbase;
+    return (this->pptr - this->pbase > 0) ? this->pptr - this->pbase : 0;
 }
 
 /* Unexported */
diff --git a/dlls/msvcirt/tests/msvcirt.c b/dlls/msvcirt/tests/msvcirt.c
index 113bf0e..7f25cd7 100644
--- a/dlls/msvcirt/tests/msvcirt.c
+++ b/dlls/msvcirt/tests/msvcirt.c
@@ -200,7 +200,9 @@ static int (*__thiscall p_streambuf_allocate)(streambuf*);
 static void (*__thiscall p_streambuf_clrclock)(streambuf*);
 static int (*__thiscall p_streambuf_doallocate)(streambuf*);
 static void (*__thiscall p_streambuf_gbump)(streambuf*, int);
+static int (*__thiscall p_streambuf_in_avail)(const streambuf*);
 static void (*__thiscall p_streambuf_lock)(streambuf*);
+static int (*__thiscall p_streambuf_out_waiting)(const streambuf*);
 static int (*__thiscall p_streambuf_pbackfail)(streambuf*, int);
 static void (*__thiscall p_streambuf_pbump)(streambuf*, int);
 static int (*__thiscall p_streambuf_sbumpc)(streambuf*);
@@ -480,7 +482,9 @@ static BOOL init(void)
         SET(p_streambuf_clrclock, "?clrlock(a)streambuf@@QEAAXXZ");
         SET(p_streambuf_doallocate, "?doallocate(a)streambuf@@MEAAHXZ");
         SET(p_streambuf_gbump, "?gbump(a)streambuf@@IEAAXH(a)Z");
+        SET(p_streambuf_in_avail, "?in_avail(a)streambuf@@QEBAHXZ");
         SET(p_streambuf_lock, "?lock(a)streambuf@@QEAAXXZ");
+        SET(p_streambuf_out_waiting, "?out_waiting(a)streambuf@@QEBAHXZ");
         SET(p_streambuf_pbackfail, "?pbackfail(a)streambuf@@UEAAHH(a)Z");
         SET(p_streambuf_pbump, "?pbump(a)streambuf@@IEAAXH(a)Z");
         SET(p_streambuf_sbumpc, "?sbumpc(a)streambuf@@QEAAHXZ");
@@ -657,7 +661,9 @@ static BOOL init(void)
         SET(p_streambuf_clrclock, "?clrlock(a)streambuf@@QAEXXZ");
         SET(p_streambuf_doallocate, "?doallocate(a)streambuf@@MAEHXZ");
         SET(p_streambuf_gbump, "?gbump(a)streambuf@@IAEXH(a)Z");
+        SET(p_streambuf_in_avail, "?in_avail(a)streambuf@@QBEHXZ");
         SET(p_streambuf_lock, "?lock(a)streambuf@@QAEXXZ");
+        SET(p_streambuf_out_waiting, "?out_waiting(a)streambuf@@QBEHXZ");
         SET(p_streambuf_pbackfail, "?pbackfail(a)streambuf@@UAEHH(a)Z");
         SET(p_streambuf_pbump, "?pbump(a)streambuf@@IAEXH(a)Z");
         SET(p_streambuf_sbumpc, "?sbumpc(a)streambuf@@QAEHXZ");
@@ -1388,6 +1394,36 @@ static void test_streambuf(void)
     ok(sb2.gptr == sb2.egptr, "wrong get pointer, expected %p got %p\n", sb2.egptr, sb2.gptr);
     ok(*sb2.gptr == 'X', "expected 'X' in the get area, got %c\n", *sb2.gptr);
 
+    /* out_waiting */
+    ret = (int) call_func1(p_streambuf_out_waiting, &sb);
+    ok(ret == 9, "expected 9 got %d\n", ret);
+    sb.pptr = sb.pbase;
+    ret = (int) call_func1(p_streambuf_out_waiting, &sb);
+    ok(ret == 0, "expected 0 got %d\n", ret);
+    sb.pptr = sb.pbase - 1;
+    ret = (int) call_func1(p_streambuf_out_waiting, &sb);
+    ok(ret == 0, "expected 0 got %d\n", ret);
+    sb.pptr = NULL;
+    ret = (int) call_func1(p_streambuf_out_waiting, &sb);
+    ok(ret == 0, "expected 0 got %d\n", ret);
+    sb.pptr = sb.epptr;
+    sb.pbase = NULL;
+    ret = (int) call_func1(p_streambuf_out_waiting, &sb);
+    ok(ret == (int)(sb.pptr - sb.pbase), "expected %d got %d\n", (int)(sb.pptr - sb.pbase), ret);
+
+    /* in_avail */
+    ret = (int) call_func1(p_streambuf_in_avail, &sb);
+    ok(ret == 256, "expected 256 got %d\n", ret);
+    sb.gptr = sb.egptr;
+    ret = (int) call_func1(p_streambuf_in_avail, &sb);
+    ok(ret == 0, "expected 0 got %d\n", ret);
+    sb.gptr = sb.egptr + 1;
+    ret = (int) call_func1(p_streambuf_in_avail, &sb);
+    ok(ret == 0, "expected 0 got %d\n", ret);
+    sb.egptr = NULL;
+    ret = (int) call_func1(p_streambuf_in_avail, &sb);
+    ok(ret == 0, "expected 0 got %d\n", ret);
+
     SetEvent(lock_arg.test[3]);
     WaitForSingleObject(thread, INFINITE);