# include <unistd.h>
#endif
-#ifdef HAVE_MMAP
-# include <sys/mman.h>
-#endif
-
#include <errno.h>
#include <string.h>
#endif
}
-
-/**********************************************************************
- * GStreamer Default File Source
- * Theory of Operation
- *
- * Update: see GstFileSrc:use-mmap property documentation below
- * for why use of mmap() is disabled by default.
- *
- * This source uses mmap(2) to efficiently load data from a file.
- * To do this without seriously polluting the applications' memory
- * space, it must do so in smaller chunks, say 1-4MB at a time.
- * Buffers are then subdivided from these mmap'd chunks, to directly
- * make use of the mmap.
- *
- * To handle refcounting so that the mmap can be freed at the appropriate
- * time, a buffer will be created for each mmap'd region, and all new
- * buffers will be sub-buffers of this top-level buffer. As they are
- * freed, the refcount goes down on the mmap'd buffer and its free()
- * function is called, which will call munmap(2) on itself.
- *
- * If a buffer happens to cross the boundaries of an mmap'd region, we
- * have to decide whether it's more efficient to copy the data into a
- * new buffer, or mmap() just that buffer. There will have to be a
- * breakpoint size to determine which will be done. The mmap() size
- * has a lot to do with this as well, because you end up in double-
- * jeopardy: the larger the outgoing buffer, the more data to copy when
- * it overlaps, *and* the more frequently you'll have buffers that *do*
- * overlap.
- *
- * Seeking is another tricky aspect to do efficiently. The initial
- * implementation of this source won't make use of these features, however.
- * The issue is that if an application seeks backwards in a file, *and*
- * that region of the file is covered by an mmap that hasn't been fully
- * deallocated, we really should re-use it. But keeping track of these
- * regions is tricky because we have to lock the structure that holds
- * them. We need to settle on a locking primitive (GMutex seems to be
- * a really good option...), then we can do that.
- */
-
-
GST_DEBUG_CATEGORY_STATIC (gst_file_src_debug);
#define GST_CAT_DEFAULT gst_file_src_debug
};
#define DEFAULT_BLOCKSIZE 4*1024
-#define DEFAULT_MMAPSIZE 4*1024*1024
-#define DEFAULT_TOUCH TRUE
-#define DEFAULT_USEMMAP FALSE
-#define DEFAULT_SEQUENTIAL FALSE
enum
{
- ARG_0,
- ARG_LOCATION,
- ARG_FD,
- ARG_MMAPSIZE,
- ARG_SEQUENTIAL,
- ARG_TOUCH,
- ARG_USEMMAP
+ PROP_0,
+ PROP_LOCATION,
+ PROP_FD
};
static void gst_file_src_finalize (GObject * object);
gobject_class->set_property = gst_file_src_set_property;
gobject_class->get_property = gst_file_src_get_property;
- g_object_class_install_property (gobject_class, ARG_FD,
+ g_object_class_install_property (gobject_class, PROP_FD,
g_param_spec_int ("fd", "File-descriptor",
"File-descriptor for the file being mmap()d", 0, G_MAXINT, 0,
G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
- g_object_class_install_property (gobject_class, ARG_LOCATION,
+ g_object_class_install_property (gobject_class, PROP_LOCATION,
g_param_spec_string ("location", "File Location",
"Location of the file to read", NULL,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
GST_PARAM_MUTABLE_READY));
- g_object_class_install_property (gobject_class, ARG_MMAPSIZE,
- g_param_spec_ulong ("mmapsize", "mmap() Block Size",
- "Size in bytes of mmap()d regions", 0, G_MAXULONG, DEFAULT_MMAPSIZE,
- G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
- GST_PARAM_MUTABLE_PLAYING));
- g_object_class_install_property (gobject_class, ARG_TOUCH,
- g_param_spec_boolean ("touch", "Touch mapped region read data",
- "Touch mmapped data regions to force them to be read from disk",
- DEFAULT_TOUCH,
- G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
- GST_PARAM_MUTABLE_PLAYING));
- /**
- * GstFileSrc:use-mmap
- *
- * Whether to use mmap(). Set to TRUE to force use of mmap() instead of
- * read() for reading data.
- *
- * Use of mmap() is disabled by default since with mmap() there are a
- * number of occasions where the process/application will be notified of
- * read errors via a SIGBUS signal from the kernel, which will lead to
- * the application being killed if not handled by the application. This
- * is something that is difficult to work around for a library like
- * GStreamer, hence use of mmap() is disabled by default. Said errors
- * can occur for example when an external device (e.g. an external hard
- * drive or a portable music player) are unplugged while in use, or when
- * a CD/DVD medium cannot be be read because the medium is scratched or
- * otherwise damaged.
- *
- **/
- g_object_class_install_property (gobject_class, ARG_USEMMAP,
- g_param_spec_boolean ("use-mmap", "Use mmap to read data",
- "Whether to use mmap() instead of read()",
- DEFAULT_USEMMAP, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
- GST_PARAM_MUTABLE_READY));
- g_object_class_install_property (gobject_class, ARG_SEQUENTIAL,
- g_param_spec_boolean ("sequential", "Optimise for sequential mmap access",
- "Whether to use madvise to hint to the kernel that access to "
- "mmap pages will be sequential",
- DEFAULT_SEQUENTIAL, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS |
- GST_PARAM_MUTABLE_PLAYING));
gobject_class->finalize = gst_file_src_finalize;
static void
gst_file_src_init (GstFileSrc * src)
{
-#ifdef HAVE_MMAP
- src->pagesize = getpagesize ();
-#endif
-
src->filename = NULL;
src->fd = 0;
src->uri = NULL;
- src->touch = DEFAULT_TOUCH;
-
- src->mapbuf = NULL;
- src->mapsize = DEFAULT_MMAPSIZE; /* default is 4MB */
- src->use_mmap = DEFAULT_USEMMAP;
- src->sequential = DEFAULT_SEQUENTIAL;
-
src->is_regular = FALSE;
}
src = GST_FILE_SRC (object);
switch (prop_id) {
- case ARG_LOCATION:
+ case PROP_LOCATION:
gst_file_src_set_location (src, g_value_get_string (value));
break;
- case ARG_MMAPSIZE:
- if ((src->mapsize % src->pagesize) == 0) {
- src->mapsize = g_value_get_ulong (value);
- } else {
- GST_INFO_OBJECT (src,
- "invalid mapsize, must be a multiple of pagesize, which is %d",
- src->pagesize);
- }
- break;
- case ARG_TOUCH:
- src->touch = g_value_get_boolean (value);
- break;
- case ARG_SEQUENTIAL:
- src->sequential = g_value_get_boolean (value);
- break;
- case ARG_USEMMAP:
- src->use_mmap = g_value_get_boolean (value);
- break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
src = GST_FILE_SRC (object);
switch (prop_id) {
- case ARG_LOCATION:
+ case PROP_LOCATION:
g_value_set_string (value, src->filename);
break;
- case ARG_FD:
+ case PROP_FD:
g_value_set_int (value, src->fd);
break;
- case ARG_MMAPSIZE:
- g_value_set_ulong (value, src->mapsize);
- break;
- case ARG_TOUCH:
- g_value_set_boolean (value, src->touch);
- break;
- case ARG_SEQUENTIAL:
- g_value_set_boolean (value, src->sequential);
- break;
- case ARG_USEMMAP:
- g_value_set_boolean (value, src->use_mmap);
- break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
-#undef HAVE_MMAP
-/***
- * mmap code below
- */
-
-#ifdef HAVE_MMAP
-
-/* GstMmapBuffer */
-
-typedef struct _GstMmapBuffer GstMmapBuffer;
-typedef struct _GstMmapBufferClass GstMmapBufferClass;
-
-#define GST_TYPE_MMAP_BUFFER (gst_mmap_buffer_get_type())
-
-#define GST_IS_MMAP_BUFFER(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_MMAP_BUFFER))
-#define GST_IS_MMAP_BUFFER_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_MMAP_BUFFER))
-#define GST_MMAP_BUFFER_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_MMAP_BUFFER, GstMmapBufferClass))
-#define GST_MMAP_BUFFER(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_MMAP_BUFFER, GstMmapBuffer))
-#define GST_MMAP_BUFFER_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_MMAP_BUFFER, GstMmapBufferClass))
-
-
-
-struct _GstMmapBuffer
-{
- GstBuffer buffer;
-
- GstFileSrc *filesrc;
-};
-
-struct _GstMmapBufferClass
-{
- GstBufferClass buffer_class;
-};
-
-static void gst_mmap_buffer_finalize (GstMmapBuffer * mmap_buffer);
-
-GType gst_mmap_buffer_get_type (void);
-
-G_DEFINE_TYPE (GstMmapBuffer, gst_mmap_buffer, GST_TYPE_BUFFER);
-
-static void
-gst_mmap_buffer_class_init (GstMmapBufferClass * g_class)
-{
- GstMiniObjectClass *mini_object_class = GST_MINI_OBJECT_CLASS (g_class);
-
- mini_object_class->finalize =
- (GstMiniObjectFinalizeFunction) gst_mmap_buffer_finalize;
-}
-
-static void
-gst_mmap_buffer_init (GstMmapBuffer * buf)
-{
- GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_READONLY);
- /* before we re-enable this flag, we probably need to fix _copy()
- * _make_writable(), etc. in GstMiniObject/GstBuffer as well */
- /* GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_ORIGINAL); */
-}
-
-static void
-gst_mmap_buffer_finalize (GstMmapBuffer * mmap_buffer)
-{
- guint size;
- gpointer data;
- guint64 offset;
- GstFileSrc *src;
- GstBuffer *buffer = GST_BUFFER (mmap_buffer);
-
- /* get info */
- size = GST_BUFFER_SIZE (buffer);
- offset = GST_BUFFER_OFFSET (buffer);
- data = GST_BUFFER_DATA (buffer);
- src = mmap_buffer->filesrc;
-
- GST_LOG ("freeing mmap()d buffer at %" G_GUINT64_FORMAT "+%u", offset, size);
-
-#ifdef MADV_DONTNEED
- /* madvise to tell the kernel what to do with it */
- if (madvise (data, size, MADV_DONTNEED) < 0) {
- GST_WARNING_OBJECT (src, "warning: madvise failed: %s", g_strerror (errno));
- }
-#endif
-
- /* now unmap the memory */
- if (munmap (data, size) < 0) {
- GST_WARNING_OBJECT (src, "warning: munmap failed: %s", g_strerror (errno));
- }
-
- /* cast to unsigned long, since there's no gportable way to print
- * guint64 as hex */
- GST_LOG ("unmapped region %08lx+%08lx at %p",
- (gulong) offset, (gulong) size, data);
-
- GST_MINI_OBJECT_CLASS (gst_mmap_buffer_parent_class)->finalize
- (GST_MINI_OBJECT (mmap_buffer));
-}
-
-static GstBuffer *
-gst_file_src_map_region (GstFileSrc * src, off_t offset, gsize size,
- gboolean testonly)
-{
- GstBuffer *buf;
- void *mmapregion;
-
- g_return_val_if_fail (offset >= 0, NULL);
-
- /* FIXME ? use goffset and friends if we require glib >= 2.20 */
- GST_LOG_OBJECT (src, "mapping region %08" G_GINT64_MODIFIER "x+%08lx "
- "from file into memory", (gint64) offset, (gulong) size);
-
- mmapregion = mmap (NULL, size, PROT_READ, MAP_SHARED, src->fd, offset);
-
- if (mmapregion == NULL || mmapregion == MAP_FAILED)
- goto mmap_failed;
-
- GST_LOG_OBJECT (src, "mapped region %08lx+%08lx from file into memory at %p",
- (gulong) offset, (gulong) size, mmapregion);
-
- /* time to allocate a new mapbuf */
- buf = (GstBuffer *) gst_mini_object_new (GST_TYPE_MMAP_BUFFER);
- /* mmap() the data into this new buffer */
- GST_BUFFER_DATA (buf) = mmapregion;
- GST_MMAP_BUFFER (buf)->filesrc = src;
-
-#ifdef MADV_SEQUENTIAL
- if (src->sequential) {
- /* madvise to tell the kernel what to do with it */
- if (madvise (mmapregion, size, MADV_SEQUENTIAL) < 0) {
- GST_WARNING_OBJECT (src, "warning: madvise failed: %s",
- g_strerror (errno));
- }
- }
-#endif
-
- /* fill in the rest of the fields */
- GST_BUFFER_SIZE (buf) = size;
- GST_BUFFER_OFFSET (buf) = offset;
- GST_BUFFER_OFFSET_END (buf) = offset + size;
- GST_BUFFER_TIMESTAMP (buf) = GST_CLOCK_TIME_NONE;
-
- return buf;
-
- /* ERROR */
-mmap_failed:
- {
- if (!testonly) {
- GST_ELEMENT_ERROR (src, RESOURCE, READ, (NULL),
- ("mmap (0x%08lx, %d, 0x%" G_GINT64_MODIFIER "x) failed: %s",
- (gulong) size, src->fd, (guint64) offset, g_strerror (errno)));
- }
- return NULL;
- }
-}
-
-static GstBuffer *
-gst_file_src_map_small_region (GstFileSrc * src, off_t offset, gsize size)
-{
- GstBuffer *ret;
- off_t mod;
- guint pagesize;
-
- GST_LOG_OBJECT (src,
- "attempting to map a small buffer at %" G_GUINT64_FORMAT "+%d",
- (guint64) offset, (gint) size);
-
- pagesize = src->pagesize;
-
- mod = offset % pagesize;
-
- /* if the offset starts at a non-page boundary, we have to special case */
- if (mod != 0) {
- gsize mapsize;
- off_t mapbase;
- GstBuffer *map;
-
- mapbase = offset - mod;
- mapsize = ((size + mod + pagesize - 1) / pagesize) * pagesize;
-
- GST_LOG_OBJECT (src,
- "not on page boundaries, resizing to map to %" G_GUINT64_FORMAT "+%d",
- (guint64) mapbase, (gint) mapsize);
-
- map = gst_file_src_map_region (src, mapbase, mapsize, FALSE);
- if (map == NULL)
- return NULL;
-
- ret = gst_buffer_create_sub (map, offset - mapbase, size);
- GST_BUFFER_OFFSET (ret) = GST_BUFFER_OFFSET (map) + offset - mapbase;
-
- gst_buffer_unref (map);
- } else {
- ret = gst_file_src_map_region (src, offset, size, FALSE);
- }
-
- return ret;
-}
-
-static GstFlowReturn
-gst_file_src_create_mmap (GstFileSrc * src, guint64 offset, guint length,
- GstBuffer ** buffer)
-{
- GstBuffer *buf = NULL;
- gsize readsize, mapsize;
- off_t readend, mapstart, mapend;
- int i;
-
- /* calculate end pointers so we don't have to do so repeatedly later */
- readsize = length;
- readend = offset + readsize; /* note this is the byte *after* the read */
-
- mapstart = GST_BUFFER_OFFSET (src->mapbuf);
- mapsize = GST_BUFFER_SIZE (src->mapbuf);
- mapend = mapstart + mapsize; /* note this is the byte *after* the map */
-
- GST_LOG ("attempting to read %08lx, %08lx, %08lx, %08lx",
- (unsigned long) readsize, (unsigned long) readend,
- (unsigned long) mapstart, (unsigned long) mapend);
-
- /* if the start is past the mapstart */
- if (offset >= mapstart) {
- /* if the end is before the mapend, the buffer is in current mmap region... */
- /* ('cause by definition if readend is in the buffer, so's readstart) */
- if (readend <= mapend) {
- GST_LOG_OBJECT (src, "read buf %" G_GUINT64_FORMAT "+%u lives in "
- "current mapbuf %u+%u, creating subbuffer of mapbuf",
- offset, (guint) readsize, (guint) mapstart, (guint) mapsize);
- buf = gst_buffer_create_sub (src->mapbuf, offset - mapstart, readsize);
- GST_BUFFER_OFFSET (buf) = offset;
-
- /* if the start actually is within the current mmap region, map an overlap buffer */
- } else if (offset < mapend) {
- GST_LOG_OBJECT (src, "read buf %" G_GUINT64_FORMAT "+%u starts in "
- "mapbuf %u+%u but ends outside, creating new mmap",
- offset, (guint) readsize, (guint) mapstart, (guint) mapsize);
- buf = gst_file_src_map_small_region (src, offset, readsize);
- if (buf == NULL)
- goto could_not_mmap;
- }
-
- /* the only other option is that buffer is totally outside, which means we search for it */
-
- /* now we can assume that the start is *before* the current mmap region */
- /* if the readend is past mapstart, we have two options */
- } else if (readend >= mapstart) {
- /* either the read buffer overlaps the start of the mmap region */
- /* or the read buffer fully contains the current mmap region */
- /* either way, it's really not relevant, we just create a new region anyway */
- GST_LOG_OBJECT (src, "read buf %" G_GUINT64_FORMAT "+%d starts before "
- "mapbuf %d+%d, but overlaps it", (guint64) offset, (gint) readsize,
- (gint) mapstart, (gint) mapsize);
- buf = gst_file_src_map_small_region (src, offset, readsize);
- if (buf == NULL)
- goto could_not_mmap;
- }
-
- /* then deal with the case where the read buffer is totally outside */
- if (buf == NULL) {
- /* first check to see if there's a map that covers the right region already */
- GST_LOG_OBJECT (src, "searching for mapbuf to cover %" G_GUINT64_FORMAT
- "+%d", offset, (int) readsize);
-
- /* if the read buffer crosses a mmap region boundary, create a one-off region */
- if ((offset / src->mapsize) != (readend / src->mapsize)) {
- GST_LOG_OBJECT (src, "read buf %" G_GUINT64_FORMAT "+%d crosses a "
- "%d-byte boundary, creating a one-off", offset, (int) readsize,
- (int) src->mapsize);
- buf = gst_file_src_map_small_region (src, offset, readsize);
- if (buf == NULL)
- goto could_not_mmap;
-
- /* otherwise we will create a new mmap region and set it to the default */
- } else {
- gsize mapsize;
-
- off_t nextmap = offset - (offset % src->mapsize);
-
- GST_LOG_OBJECT (src, "read buf %" G_GUINT64_FORMAT "+%d in new mapbuf "
- "at %" G_GUINT64_FORMAT "+%d, mapping and subbuffering",
- offset, (gint) readsize, (guint64) nextmap, (gint) src->mapsize);
- /* first, we're done with the old mapbuf */
- gst_buffer_unref (src->mapbuf);
- mapsize = src->mapsize;
-
- /* double the mapsize as long as the readsize is smaller */
- while (readsize + offset > nextmap + mapsize) {
- GST_LOG_OBJECT (src, "readsize smaller then mapsize %08x %d",
- (guint) readsize, (gint) mapsize);
- mapsize <<= 1;
- }
- /* create a new one */
- src->mapbuf = gst_file_src_map_region (src, nextmap, mapsize, FALSE);
- if (src->mapbuf == NULL)
- goto could_not_mmap;
-
- /* subbuffer it */
- buf = gst_buffer_create_sub (src->mapbuf, offset - nextmap, readsize);
- GST_BUFFER_OFFSET (buf) =
- GST_BUFFER_OFFSET (src->mapbuf) + offset - nextmap;
- }
- }
-
- /* if we need to touch the buffer (to bring it into memory), do so */
- if (src->touch) {
- volatile guchar *p = GST_BUFFER_DATA (buf);
-
- /* read first byte of each page */
- for (i = 0; i < GST_BUFFER_SIZE (buf); i += src->pagesize)
- (void) p[i];
- }
-
- /* we're done, return the buffer */
- *buffer = buf;
-
- return GST_FLOW_OK;
-
- /* ERROR */
-could_not_mmap:
- {
- return GST_FLOW_ERROR;
- }
-}
-#endif
-
/***
* read code below
* that is to say, you shouldn't read the code below, but the code that reads
* the sort of attitude we want to be advertising. No sir.
*
*/
-
static GstFlowReturn
gst_file_src_create_read (GstFileSrc * src, guint64 offset, guint length,
GstBuffer ** buffer)
src = GST_FILE_SRC_CAST (basesrc);
-#ifdef HAVE_MMAP
- if (src->using_mmap) {
- ret = gst_file_src_create_mmap (src, offset, length, buffer);
- } else {
- ret = gst_file_src_create_read (src, offset, length, buffer);
- }
-#else
ret = gst_file_src_create_read (src, offset, length, buffer);
-#endif
return ret;
}
if (S_ISSOCK (stat_results.st_mode))
goto was_socket;
- src->using_mmap = FALSE;
src->read_position = 0;
/* record if it's a regular (hence seekable and lengthable) file */
if (S_ISREG (stat_results.st_mode))
src->is_regular = TRUE;
-#ifdef HAVE_MMAP
- if (src->use_mmap) {
- /* FIXME: maybe we should only try to mmap if it's a regular file */
- /* allocate the first mmap'd region if it's a regular file ? */
- src->mapbuf = gst_file_src_map_region (src, 0, src->mapsize, TRUE);
- if (src->mapbuf != NULL) {
- GST_DEBUG_OBJECT (src, "using mmap for file");
- src->using_mmap = TRUE;
- src->seekable = TRUE;
- }
- }
- if (src->mapbuf == NULL)
-#endif
+ /* We need to check if the underlying file is seekable. */
{
- /* If not in mmap mode, we need to check if the underlying file is
- * seekable. */
off_t res = lseek (src->fd, 0, SEEK_END);
if (res < 0) {
src->fd = 0;
src->is_regular = FALSE;
- if (src->mapbuf) {
- gst_buffer_unref (src->mapbuf);
- src->mapbuf = NULL;
- }
-
return TRUE;
}
projects / platform / upstream / gstreamer.git / commitdiff