ibuf: don't clash with tarantool's ibuf_*() symbols

HACKING.md

@@ -0,0 +1,18 @@
+# Hacking
+
+Here we collect arcane knowledge, which may be useful for developers of the
+module.
+
+## memcached_ibuf
+
+`third_party/memcached_ibuf.[ch]` is the copy of ibuf from the small library
+with renaming of the functions. The motivation is to avoid possible name clash
+between tarantool's symbols and the module's symbols. See [1] and [2] for
+details.
+
+We can remove it, when we'll dedice to drop support of tarantool versions
+affected by [1] or will find another way to overcome the name clash (see [3]).
+
+[1]: https://github.com/tarantool/tarantool/issues/6873
+[2]: https://github.com/tarantool/memcached/issues/59#issuecomment-1081106140
+[3]: https://github.com/tarantool/memcached/issues/92#issuecomment-1081128938

README.md

@@ -190,3 +190,8 @@ For custom configuration file path, please, use `SASL_CONF_PATH` environment var
 ## Caution
 
 This rock is in early beta.
+
+## Hacking
+
+We're collecting information for the module developers in the
+[HACKING.md](HACKING.md) file.

memcached/CMakeLists.txt

@@ -40,6 +40,7 @@ add_library(internalso SHARED
         "internal/expiration.c"
         "internal/memcached.c"
         "internal/mc_sasl.c"
+        "${CMAKE_SOURCE_DIR}/third_party/memcached_ibuf.c"
 )
 
 target_link_libraries(internalso msgpuck)

memcached/internal/memcached.c

@@ -34,11 +34,11 @@
 #include <stdbool.h>
 
 #include <tarantool/module.h>
-#include <small/ibuf.h>
 #include <small/obuf.h>
 
 #include "alloc.h"
 #include "memcached.h"
+#include "memcached_ibuf.h"
 #include "memcached_layer.h"
 #include "error.h"
 #include "network.h"
@@ -56,9 +56,9 @@ destroy_allocations()  {
 static inline int
 memcached_skip_request(struct memcached_connection *con) {
 	struct ibuf *in = con->in;
-	while (ibuf_used(in) < con->len && con->noprocess) {
-		con->len -= ibuf_used(in);
-		ibuf_reset(in);
+	while (memcached_ibuf_used(in) < con->len && con->noprocess) {
+		con->len -= memcached_ibuf_used(in);
+		memcached_ibuf_reset(in);
 		ssize_t read = mnet_read_ibuf(con->fd, in, 1);
 		if (read == -1)
 			memcached_error_ENOMEM(1, "ibuf");
@@ -77,10 +77,10 @@ memcached_flush(struct memcached_connection *con) {
 				    obuf_iovcnt(con->out),
 				    obuf_size(con->out));
 	con->cfg->stat.bytes_written += total;
-	if (ibuf_used(con->in) == 0)
-		ibuf_reset(con->in);
+	if (memcached_ibuf_used(con->in) == 0)
+		memcached_ibuf_reset(con->in);
 	obuf_reset(con->out);
-	if (ibuf_reserve(con->in, con->cfg->readahead) == NULL)
+	if (memcached_ibuf_reserve(con->in, con->cfg->readahead) == NULL)
 		return -1;
 	return total;
 }
@@ -99,7 +99,7 @@ memcached_connection_gc(struct memcached_connection *con)
 static inline int
 memcached_loop_read(struct memcached_connection *con, size_t to_read)
 {
-	if (ibuf_reserve(con->in, to_read) == NULL) {
+	if (memcached_ibuf_reserve(con->in, to_read) == NULL) {
 /*		memcached_error_ENOMEM(to_read, "ibuf");*/
 		return -1;
 	}
@@ -205,7 +205,7 @@ memcached_loop(struct memcached_connection *con)
 		if (con->close_connection) {
 			say_debug("Requesting exit. Exiting.");
 			break;
-		} else if (rc == 0 && ibuf_used(con->in) > 0 &&
+		} else if (rc == 0 && memcached_ibuf_used(con->in) > 0 &&
 			   batch_count < con->cfg->batch_count) {
 			batch_count++;
 			goto next;
@@ -215,7 +215,7 @@ memcached_loop(struct memcached_connection *con)
 			memcached_flush(con);
 		fiber_reschedule();
 		batch_count = 0;
-		if (ibuf_used(con->in) > 0) {
+		if (memcached_ibuf_used(con->in) > 0) {
 			goto next;
 		}
 		continue;

memcached/internal/network.c

@@ -11,11 +11,11 @@
 
 #include <tarantool/module.h>
 #include <small/mempool.h>
-#include <small/ibuf.h>
 #include <small/obuf.h>
 
 #include "alloc.h"
 #include "memcached.h"
+#include "memcached_ibuf.h"
 #include "constants.h"
 #include "network.h"
 
@@ -49,7 +49,8 @@ ibuf_new()
 {
 	void *ibuf = mempool_alloc(&ibuf_pool);
 	if (ibuf == NULL) return NULL;
-	ibuf_create((struct ibuf *)ibuf, memcached_slab_cache(), iobuf_readahead);
+	memcached_ibuf_create((struct ibuf *)ibuf, memcached_slab_cache(),
+			      iobuf_readahead);
 	return ibuf;
 }
 
@@ -65,7 +66,7 @@ obuf_new()
 void
 iobuf_delete(struct ibuf *ibuf, struct obuf *obuf)
 {
-	ibuf_destroy(ibuf);
+	memcached_ibuf_destroy(ibuf);
 	obuf_destroy(obuf);
 	mempool_free(&ibuf_pool, ibuf);
 	mempool_free(&obuf_pool, obuf);
@@ -148,10 +149,11 @@ mnet_read_ahead(int fd, void *buf, size_t bufsz, size_t sz)
 size_t
 mnet_read_ibuf(int fd, struct ibuf *buf, size_t sz)
 {
-	if (ibuf_reserve(buf, sz) == NULL) {
+	if (memcached_ibuf_reserve(buf, sz) == NULL) {
 		return -1;
 	}
-	ssize_t n = mnet_read_ahead(fd, buf->wpos, ibuf_unused(buf), sz);
+	ssize_t n = mnet_read_ahead(fd, buf->wpos, memcached_ibuf_unused(buf),
+				    sz);
 	buf->wpos += n;
 	return n;
 }

memcached/internal/network.h

@@ -3,7 +3,7 @@
 
 #define TIMEOUT_INFINITY 365*86400*100.0
 
-#include <small/ibuf.h>
+#include "memcached_ibuf.h"
 
 size_t
 mnet_writev(int fd, struct iovec *iov, int iovcnt, size_t size_hint);

memcached/internal/proto_bin.c

@@ -15,7 +15,7 @@
 #include "memcached_layer.h"
 #include "mc_sasl.h"
 
-#include <small/ibuf.h>
+#include "memcached_ibuf.h"
 #include <small/obuf.h>
 
 static inline int

memcached/internal/proto_txt.c

@@ -4,10 +4,10 @@
 
 #include <tarantool/module.h>
 #include <msgpuck.h>
-#include <small/ibuf.h>
 #include <small/obuf.h>
 
 #include "memcached.h"
+#include "memcached_ibuf.h"
 #include "constants.h"
 #include "memcached_layer.h"
 #include "error.h"

third_party/memcached_ibuf.c

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2010-2016, Tarantool AUTHORS, please see AUTHORS file.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above
+ *    copyright notice, this list of conditions and the
+ *    following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials
+ *    provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY <COPYRIGHT HOLDER> ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+ * <COPYRIGHT HOLDER> OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+ * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#include "memcached_ibuf.h"
+#include <string.h>
+#include <small/slab_cache.h>
+
+/** Initialize an input buffer. */
+void
+memcached_ibuf_create(struct ibuf *ibuf, struct slab_cache *slabc,
+		      size_t start_capacity)
+{
+	ibuf->slabc = slabc;
+	ibuf->buf = ibuf->rpos = ibuf->wpos = ibuf->end = NULL;
+	ibuf->start_capacity = start_capacity;
+	/* Don't allocate the buffer yet. */
+}
+
+void
+memcached_ibuf_destroy(struct ibuf *ibuf)
+{
+	if (ibuf->buf) {
+		struct slab *slab = slab_from_data(ibuf->buf);
+		slab_put(ibuf->slabc, slab);
+	 }
+}
+
+/** Free memory allocated by this buffer */
+void
+memcached_ibuf_reinit(struct ibuf *ibuf)
+{
+	struct slab_cache *slabc = ibuf->slabc;
+	size_t start_capacity = ibuf->start_capacity;
+	memcached_ibuf_destroy(ibuf);
+	memcached_ibuf_create(ibuf, slabc, start_capacity);
+}
+
+/**
+ * Ensure the buffer has sufficient capacity
+ * to store size bytes, and return pointer to
+ * the beginning.
+ */
+void *
+memcached_ibuf_reserve_slow(struct ibuf *ibuf, size_t size)
+{
+	assert(ibuf->wpos + size > ibuf->end);
+	size_t used = memcached_ibuf_used(ibuf);
+	size_t capacity = memcached_ibuf_capacity(ibuf);
+	/*
+	 * Check if we have enough space in the
+	 * current buffer. In this case de-fragment it
+	 * by moving existing data to the beginning.
+	 * Otherwise, get a bigger buffer.
+	 */
+	if (size + used <= capacity) {
+		memmove(ibuf->buf, ibuf->rpos, used);
+	} else {
+		/* Use iobuf_readahead as allocation factor. */
+		size_t new_capacity = capacity * 2;
+		if (new_capacity < ibuf->start_capacity)
+			new_capacity = ibuf->start_capacity;
+
+		while (new_capacity < used + size)
+			new_capacity *= 2;
+
+		struct slab *slab = slab_get(ibuf->slabc, new_capacity);
+		if (slab == NULL)
+			return NULL;
+		char *ptr = (char *) slab_data(slab);
+		memcpy(ptr, ibuf->rpos, used);
+		if (ibuf->buf)
+			slab_put(ibuf->slabc, slab_from_data(ibuf->buf));
+		ibuf->buf = ptr;
+		ibuf->end = ibuf->buf + slab_capacity(slab);
+	}
+	ibuf->rpos = ibuf->buf;
+	ibuf->wpos = ibuf->rpos + used;
+	return ibuf->wpos;
+}
+