The function owns the resulting file descriptor and will close it
when finished transferring data.
- The results of using evbuffer_remove() or evbuffer_pullup() are
- undefined.
+ The results of using evbuffer_remove() or evbuffer_pullup() on
+ evbuffers whose data was added using this function are undefined.
+ For more fine-grained control, use evbuffer_add_file_segment.
+
@param outbuf the output buffer
@param fd the file descriptor
++<<<<<<< HEAD
+ @param off the offset from which to read data
+ @param length how much data to read, or -1 to read as much as possible.
+ (-1 requires that 'fd' support fstat.)
++||||||| merged common ancestors
++ @param off the offset from which to read data
++ @param length how much data to read
++=======
+ @param offset the offset from which to read data
+ @param length how much data to read
++>>>>>>> origin/patches-2.0
@return 0 if successful, or -1 if an error occurred
*/
- int evbuffer_add_file(struct evbuffer *output, int fd, ev_off_t offset,
+ int evbuffer_add_file(struct evbuffer *outbuf, int fd, ev_off_t offset,
ev_off_t length);
+/**
+ An evbuffer_file_segment holds a reference to a range of a file --
+ possibly the whole file! -- for use in writing from an evbuffer to a
+ socket. It could be implemented with mmap, sendfile, splice, or (if all
+ else fails) by just pulling all the data into RAM. A single
+ evbuffer_file_segment can be added more than once, and to more than one
+ evbuffer.
+ */
+struct evbuffer_file_segment;
+
+/**
+ Flag for creating evbuffer_file_segment: If this flag is set, then when
+ the evbuffer_file_segment is freed and no longer in use by any
+ evbuffer, the underlying fd is closed.
+ */
+#define EVBUF_FS_CLOSE_ON_FREE 0x01
+/**
+ Flag for creating evbuffer_file_segment: Disable memory-map based
+ implementations.
+ */
+#define EVBUF_FS_DISABLE_MMAP 0x02
+/**
+ Flag for creating evbuffer_file_segment: Disable direct fd-to-fd
+ implementations (including sendfile and splice).
+
+ You might want to use this option if data needs to be taken from the
+ evbuffer by any means other than writing it to the network: the sendfile
+ backend is fast, but it only works for sending files directly to the
+ network.
+ */
+#define EVBUF_FS_DISABLE_SENDFILE 0x04
+/**
+ Flag for creating evbuffer_file_segment: Do not allocate a lock for this
+ segment. If this option is set, then neither the segment nor any
+ evbuffer it is added to may ever be accessed from more than one thread
+ at a time.
+ */
+#define EVBUF_FS_DISABLE_LOCKING 0x08
+
+/**
+ Create and return a new evbuffer_file_segment for reading data from a
+ file and sending it out via an evbuffer.
+
+ This function avoids unnecessary data copies between userland and
+ kernel. Where available, it uses sendfile or splice.
+
+ The file descriptor must not be closed so long as any evbuffer is using
+ this segment.
+
+ The results of using evbuffer_remove() or evbuffer_pullup() or any other
+ function that reads bytes from an evbuffer on any evbuffer containing
+ the newly returned segment are undefined, unless you pass the
+ EVBUF_FS_DISABLE_SENDFILE flag to this function.
+
+ @param fd an open file to read from.
+ @param offset an index within the file at which to start reading
+ @param length how much data to read, or -1 to read as much as possible.
+ (-1 requires that 'fd' support fstat.)
+ @param flags any number of the EVBUF_FS_* flags
+ @return a new evbuffer_file_segment, or NULL on failure.
+ **/
+struct evbuffer_file_segment *evbuffer_file_segment_new(
+ int fd, ev_off_t offset, ev_off_t length, unsigned flags);
+
+/**
+ Free an evbuffer_file_segment
+
+ It is safe to call this function even if the segment has been added to
+ one or more evbuffers. The evbuffer_file_segment will not be freed
+ until no more references to it exist.
+ */
+void evbuffer_file_segment_free(struct evbuffer_file_segment *seg);
+
+/**
+ Insert some or all of an evbuffer_file_segment at the end of an evbuffer
+
+ Note that the offset and length parameters of this function have a
+ different meaning from those provided to evbuffer_file_segment_new: When
+ you create the segment, the offset is the offset _within the file_, and
+ the length is the length _of the segment_, whereas when you add a
+ segment to an evbuffer, the offset is _within the segment_ and the
+ length is the length of the _part of the segment you want to use.
+
+ In other words, if you have a 10 KiB file, and you create an
+ evbuffer_file_segment for it with offset 20 and length 1000, it will
+ refer to bytes 20..1019 inclusive. If you then pass this segment to
+ evbuffer_add_file_segment and specify an offset of 20 and a length of
+ 50, you will be adding bytes 40..99 inclusive.
+
+ @param buf the evbuffer to append to
+ @param seg the segment to add
+ @param offset the offset within the segment to start from
+ @param length the amount of data to add, or -1 to add it all.
+ @return 0 on success, -1 on failure.
+ */
+int evbuffer_add_file_segment(struct evbuffer *buf,
+ struct evbuffer_file_segment *seg, ev_off_t offset, ev_off_t length);
+
/**
Append a formatted string to the end of an evbuffer.
#endif
#define EV_SSIZE_MIN ((-EV_SSIZE_MAX) - 1)
+ /**@}*/
-#ifdef WIN32
+#ifdef _WIN32
#define ev_socklen_t int
#elif defined(_EVENT_socklen_t)
#define ev_socklen_t _EVENT_socklen_t
#endif
#endif
- #ifdef _WIN32
- /** A type wide enough to hold the output of "socket()" or "accept()". On
+ /**
+ * A type wide enough to hold the output of "socket()" or "accept()". On
* Windows, this is an intptr_t; elsewhere, it is an int. */
-#ifdef WIN32
++#ifdef _WIN32
#define evutil_socket_t intptr_t
#else
#define evutil_socket_t int
int evutil_closesocket(evutil_socket_t sock);
#define EVUTIL_CLOSESOCKET(s) evutil_closesocket(s)
- /* Winsock handles socket errors differently from the rest of the world.
- * Elsewhere, a socket error is like any other error and is stored in errno.
- * But winsock functions require you to retrieve the error with a special
- * function, and don't let you use strerror for the error codes. And handling
- * EWOULDBLOCK is ... different. */
-#ifdef WIN32
+#ifdef _WIN32
/** Return the most recent socket error. Not idempotent on all platforms. */
#define EVUTIL_SOCKET_ERROR() WSAGetLastError()
/** Replace the most recent socket error with errcode */
projects / libevent / commitdiff