revert 8204 -- what is happening???

git-svn-id: http://skia.googlecode.com/svn/trunk@8205 2bbb7eff-a529-9590-31e7-b0007b416f81

3 files changed, 77 insertions, 86 deletions

diff --git a/src/core/SkData.cpp b/src/core/SkData.cpp
index 8fbca7af5f..3e0c71a0e8 100644
--- a/src/core/SkData.cpp
+++ b/src/core/SkData.cpp
@@ -8,13 +8,6 @@
 #include "SkData.h"
 #include "SkFlattenableBuffers.h"
 
-#if SK_MMAP_SUPPORT
-    #include <unistd.h>
-    #include <sys/mman.h>
-    #include <fcntl.h>
-    #include <errno.h>
-#endif
-
 SK_DEFINE_INST_COUNT(SkData)
 
 SkData::SkData(const void* ptr, size_t size, ReleaseProc proc, void* context) {
@@ -127,20 +120,6 @@ SkData* SkData::NewWithCString(const char cstr[]) {
     return NewWithCopy(cstr, size);
 }
 
-#if SK_MMAP_SUPPORT
-static void sk_munmap_releaseproc(const void* addr, size_t length, void*) {
-    munmap(const_cast<void*>(addr), length);
-}
-
-SkData* SkData::NewFromMMap(const void* addr, size_t length) {
-    return SkNEW_ARGS(SkData, (addr, length, sk_munmap_releaseproc, NULL));
-}
-#else
-SkData* SkData::NewFromMMap(const void* addr, size_t length) {
-    return NULL;
-}
-#endif
-
 ///////////////////////////////////////////////////////////////////////////////
 
 void SkData::flatten(SkFlattenableWriteBuffer& buffer) const {
@@ -321,4 +300,3 @@ SkDataSet* SkDataSet::NewEmpty() {
     gEmptySet->ref();
     return gEmptySet;
 }
-
diff --git a/src/core/SkMMapStream.cpp b/src/core/SkMMapStream.cpp
new file mode 100644
index 0000000000..7388e81498
--- /dev/null
+++ b/src/core/SkMMapStream.cpp
@@ -0,0 +1,77 @@
+
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "SkMMapStream.h"
+
+#include <unistd.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <errno.h>
+
+SkMMAPStream::SkMMAPStream(const char filename[])
+{
+    fAddr = NULL;   // initialize to failure case
+    fSize = 0;
+
+    int fildes = open(filename, O_RDONLY);
+    if (fildes < 0)
+    {
+        SkDEBUGF(("---- failed to open(%s) for mmap stream error=%d\n", filename, errno));
+        return;
+    }
+
+    off_t offset = lseek(fildes, 0, SEEK_END);    // find the file size
+    if (offset == -1)
+    {
+        SkDEBUGF(("---- failed to lseek(%s) for mmap stream error=%d\n", filename, errno));
+        close(fildes);
+        return;
+    }
+    (void)lseek(fildes, 0, SEEK_SET);   // restore file offset to beginning
+
+    // to avoid a 64bit->32bit warning, I explicitly create a size_t size
+    size_t size = static_cast<size_t>(offset);
+
+    void* addr = mmap(NULL, size, PROT_READ, MAP_SHARED, fildes, 0);
+
+    // According to the POSIX documentation of mmap it adds an extra reference
+    // to the file associated with the fildes which is not removed by a
+    // subsequent close() on that fildes. This reference is removed when there
+    // are no more mappings to the file.
+    close(fildes);
+
+    if (MAP_FAILED == addr)
+    {
+        SkDEBUGF(("---- failed to mmap(%s) for mmap stream error=%d\n", filename, errno));
+        return;
+    }
+
+    this->INHERITED::setMemory(addr, size);
+
+    fAddr = addr;
+    fSize = size;
+}
+
+SkMMAPStream::~SkMMAPStream()
+{
+    this->closeMMap();
+}
+
+void SkMMAPStream::setMemory(const void* data, size_t length, bool copyData)
+{
+    this->closeMMap();
+    this->INHERITED::setMemory(data, length, copyData);
+}
+
+void SkMMAPStream::closeMMap()
+{
+    if (fAddr)
+    {
+        munmap(fAddr, fSize);
+        fAddr = NULL;
+    }
+}
diff --git a/src/core/SkStream.cpp b/src/core/SkStream.cpp
index acbcfbc53d..fb343ea76a 100644
--- a/src/core/SkStream.cpp
+++ b/src/core/SkStream.cpp
@@ -13,14 +13,6 @@
 #include "SkString.h"
 #include "SkOSFile.h"
 
-#if SK_MMAP_SUPPORT
-    #include <unistd.h>
-    #include <sys/mman.h>
-    #include <fcntl.h>
-    #include <errno.h>
-    #include <unistd.h>
-#endif
-
 SK_DEFINE_INST_COUNT(SkStream)
 SK_DEFINE_INST_COUNT(SkWStream)
 SK_DEFINE_INST_COUNT(SkFILEStream)
@@ -797,59 +789,3 @@ bool SkDebugWStream::write(const void* buffer, size_t size)
 #endif
     return true;
 }
-
-///////////////////////////////////////////////////////////////////////////////
-///////////////////////////////////////////////////////////////////////////////
-
-static bool mmap_filename(const char path[], void** addrPtr, size_t* sizePtr) {
-#if SK_MMAP_SUPPORT
-    int fd = open(path, O_RDONLY);
-    if (fd < 0) {
-        return false;
-    }
-    
-    off_t offset = lseek(fd, 0, SEEK_END);    // find the file size
-    if (offset == -1) {
-        close(fd);
-        return false;
-    }
-    (void)lseek(fd, 0, SEEK_SET);   // restore file offset to beginning
-    
-    // to avoid a 64bit->32bit warning, I explicitly create a size_t size
-    size_t size = static_cast<size_t>(offset);
-    
-    void* addr = mmap(NULL, size, PROT_READ, MAP_SHARED, fd, 0);
-    close(fd);
-    
-    if (MAP_FAILED == addr) {
-        return false;
-    }
-    
-    *addrPtr = addr;
-    *sizePtr = size;
-    return true;
-#else
-    return false;
-#endif
-}
-
-SkStream* SkStream::NewFromFile(const char path[]) {
-    void* addr;
-    size_t size;
-    if (mmap_filename(path, &addr, &size)) {
-        SkAutoTUnref<SkData> data(SkData::NewFromMMap(addr, size));
-        if (data.get()) {
-            return SkNEW_ARGS(SkMemoryStream, (data.get()));
-        }
-    }
-    
-    // If we get here, then our attempt at using mmap failed, so try normal
-    // file access.
-    SkFILEStream* stream = SkNEW_ARGS(SkFILEStream, (path));
-    if (!stream->isValid()) {
-        stream->unref();
-        stream = NULL;
-    }
-    return stream;
-}
-