Changeset 25510 in vbox

Timestamp:

Dec 19, 2009 10:19:30 PM (15 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

56183

Message:

r3/stream.cpp: serialize RTStrmPrintf on all platforms, not just the one with fwrite_unlocked.

Location:

trunk/src/VBox/Runtime

Files:

• Makefile.kmk (modified) (2 diffs)
• r3/stream.cpp (modified) (10 diffs)

trunk/src/VBox/Runtime/Makefile.kmk

@@ -556 +556 @@
         generic/RTUuidCreate-generic.cpp \
         generic/mppresent-generic.cpp \
+        generic/semrw-generic.cpp \
         generic/timer-generic.cpp \
         generic/utf16locale-generic.cpp \
@@ -579 +580 @@
         r3/posix/semeventmulti-posix.cpp \
         r3/posix/semmutex-posix.cpp \
-        r3/posix/semrw-posix.cpp \
         r3/posix/thread-posix.cpp \
         r3/posix/timelocal-posix.cpp \

trunk/src/VBox/Runtime/r3/stream.cpp

@@ -35 +35 @@
 *******************************************************************************/
 #include <iprt/stream.h>
+#include "internal/iprt.h"
+
+#include <iprt/asm.h>
+#include <iprt/critsect.h>
 #include <iprt/string.h>
-#include <iprt/asm.h>
 #include <iprt/assert.h>
 #include <iprt/alloc.h>
@@ -67 +70 @@
     int32_t volatile    i32Error;
     /** Pointer to the LIBC file stream. */
-    FILE                *pFile;
+    FILE               *pFile;
+#ifndef HAVE_FWRITE_UNLOCKED
+    /** Critical section for serializing access to the stream. */
+    PRTCRITSECT         pCritSect;
+#endif
 } RTSTREAM;
 
@@ -80 +87 @@
     0,
     stdin
+#ifndef HAVE_FWRITE_UNLOCKED
+    , NULL
+#endif
 };
 
@@ -88 +98 @@
     0,
     stderr
+#ifndef HAVE_FWRITE_UNLOCKED
+    , NULL
+#endif
 };
 
@@ -96 +109 @@
     0,
     stdout
+#ifndef HAVE_FWRITE_UNLOCKED
+    , NULL
+#endif
 };
 
@@ -106 +122 @@
 /** Pointer to the standard output stream. */
 RTDATADECL(PRTSTREAM)   g_pStdOut = &g_StdOut;
+
+
+#ifndef HAVE_FWRITE_UNLOCKED
+/**
+ * Allocates and acquires the lock for the stream.
+ *
+ * @returns IPRT status.
+ * @param   pStream     The stream (valid).
+ */
+static int rtStrmAllocLock(PRTSTREAM pStream)
+{
+    Assert(pStream->pCritSect == NULL);
+
+    PRTCRITSECT pCritSect = (PRTCRITSECT)RTMemAlloc(sizeof(*pCritSect));
+    if (!pCritSect)
+        return VERR_NO_MEMORY;
+    int rc = RTCritSectInit(pCritSect);
+    if (RT_SUCCESS(rc))
+    {
+        /* The native stream lock are normally not recursive .*/
+        pCritSect->fFlags |= RTCRITSECT_FLAGS_NO_NESTING;
+
+        rc = RTCritSectEnter(pCritSect);
+        if (RT_SUCCESS(rc))
+        {
+            if (RT_LIKELY(ASMAtomicCmpXchgPtr((void * volatile *)&pStream->pCritSect, pCritSect, NULL)))
+                return VINF_SUCCESS;
+
+            RTCritSectLeave(pCritSect);
+        }
+        RTCritSectDelete(pCritSect);
+    }
+    RTMemFree(pCritSect);
+
+    /* Handle the lost race case... */
+    pCritSect = (PRTCRITSECT)ASMAtomicReadPtr((void * volatile *)&pStream->pCritSect);
+    if (pCritSect)
+        return RTCritSectEnter(pCritSect);
+
+    return rc;
+}
+#endif /* !HAVE_FWRITE_UNLOCKED */
+
+
+/**
+ * Locks the stream.  May have to allocate the lock as well.
+ *
+ * @param   pStream     The stream (valid).
+ */
+DECLINLINE(void) rtStrmLock(PRTSTREAM pStream)
+{
+#ifdef HAVE_FWRITE_UNLOCKED
+    flockfile(pStream->pFile);
+#else
+    if (RT_LIKELY(pStream->pCritSect))
+        RTCritSectEnter(pStream->pCritSect);
+    else
+        rtStrmAllocLock(pStream);
+#endif
+}
+
+
+/**
+ * Unlocks the stream.
+ *
+ * @param   pStream     The stream (valid).
+ */
+DECLINLINE(void) rtStrmUnlock(PRTSTREAM pStream)
+{
+#ifdef HAVE_FWRITE_UNLOCKED
+    funlockfile(pStream->pFile);
+#else
+    if (RT_LIKELY(pStream->pCritSect))
+        RTCritSectLeave(pStream->pCritSect);
+#endif
+}
 
 
@@ -252 +344 @@
             pStream->u32Magic = 0xdeaddead;
             pStream->pFile = NULL;
+#ifndef HAVE_FWRITE_UNLOCKED
+            if (pStream->pCritSect)
+            {
+                RTCritSectEnter(pStream->pCritSect);
+                RTCritSectLeave(pStream->pCritSect);
+                RTCritSectDelete(pStream->pCritSect);
+                RTMemFree(pStream->pCritSect);
+                pStream->pCritSect = NULL;
+            }
+#endif
             RTMemFree(pStream);
             return VINF_SUCCESS;
         }
+
         return RTErrConvertFromErrno(errno);
     }
@@ -543 +646 @@
             {
                 cchString--;            /* save space for the terminator. */
-#ifdef HAVE_FWRITE_UNLOCKED
-                flockfile(pStream->pFile);
-#endif
+                rtStrmLock(pStream);
                 for (;;)
                 {
-#ifdef HAVE_FWRITE_UNLOCKED
+#ifdef HAVE_FWRITE_UNLOCKED /** @todo darwin + freebsd(?) has fgetc_unlocked but not fwrite_unlocked, optimize... */
                     int ch = fgetc_unlocked(pStream->pFile);
 #else
@@ -586 +687 @@
                     }
                 }
-#ifdef HAVE_FWRITE_UNLOCKED
-                funlockfile(pStream->pFile);
-#endif
+                rtStrmUnlock(pStream);
 
                 *pszString = '\0';
@@ -671 +770 @@
         if (RT_SUCCESS(rc))
         {
-            /** @todo consider making this thread safe... */
-#ifdef HAVE_FWRITE_UNLOCKED
-            flockfile(pStream->pFile);
+            rtStrmLock(pStream);
             rc = (int)RTStrFormatV(rtstrmOutput, pStream, NULL, NULL, pszFormat, args);
-            funlockfile(pStream->pFile);
-#else
-            rc = (int)RTStrFormatV(rtstrmOutput, pStream, NULL, NULL, pszFormat, args);
-#endif
+            rtStrmUnlock(pStream);
             Assert(rc >= 0);
         }