mirror of https://github.com/grpc/grpc.git
Conflicts: src/core/surface/call.c src/core/transport/chttp2_transport.c src/core/transport/transport.hpull/1888/head
Craig Tiller
10 years ago
commit
27166a6f65
502 changed files with 26942 additions and 8389 deletions
@ -0,0 +1,147 @@ |
|||||||
|
gRPC Connectivity Semantics and API |
||||||
|
=================================== |
||||||
|
|
||||||
|
This document describes the connectivity semantics for gRPC channels and the |
||||||
|
corresponding impact on RPCs. We then discuss an API. |
||||||
|
|
||||||
|
States of Connectivity |
||||||
|
---------------------- |
||||||
|
|
||||||
|
gRPC Channels provide the abstraction over which clients can communicate with |
||||||
|
servers.The client-side channel object can be constructed using little more |
||||||
|
than a DNS name. Channels encapsulate a range of functionality including name |
||||||
|
resolution, establishing a TCP connection (with retries and backoff) and TLS |
||||||
|
handshakes. Channels can also handle errors on established connections and |
||||||
|
reconnect, or in the case of HTTP/2 GO_AWAY, re-resolve the name and reconnect. |
||||||
|
|
||||||
|
To hide the details of all this activity from the user of the gRPC API (i.e., |
||||||
|
application code) while exposing meaningful information about the state of a |
||||||
|
channel, we use a state machine with four states, defined below: |
||||||
|
|
||||||
|
CONNECTING: The channel is trying to establish a connection and is waiting to |
||||||
|
make progress on one of the steps involved in name resolution, TCP connection |
||||||
|
establishment or TLS handshake. This may be used as the initial state for channels upon |
||||||
|
creation. |
||||||
|
|
||||||
|
READY: The channel has successfully established a connection all the way |
||||||
|
through TLS handshake (or equivalent) and all subsequent attempt to communicate |
||||||
|
have succeeded (or are pending without any known failure ). |
||||||
|
|
||||||
|
TRANSIENT_FAILURE: There has been some transient failure (such as a TCP 3-way |
||||||
|
handshake timing out or a socket error). Channels in this state will eventually |
||||||
|
switch to the CONNECTING state and try to establish a connection again. Since |
||||||
|
retries are done with exponential backoff, channels that fail to connect will |
||||||
|
start out spending very little time in this state but as the attempts fail |
||||||
|
repeatedly, the channel will spend increasingly large amounts of time in this |
||||||
|
state. For many non-fatal failures (e.g., TCP connection attempts timing out |
||||||
|
because the server is not yet available), the channel may spend increasingly |
||||||
|
large amounts of time in this state. |
||||||
|
|
||||||
|
IDLE: This is the state where the channel is not even trying to create a |
||||||
|
connection because of a lack of new or pending RPCs. New channels MAY be created |
||||||
|
in this state. Any attempt to start an RPC on the channel will push the channel |
||||||
|
out of this state to connecting. When there has been no RPC activity on a channel |
||||||
|
for a specified IDLE_TIMEOUT, i.e., no new or pending (active) RPCs for this |
||||||
|
period, channels that are READY or CONNECTING switch to IDLE. Additionaly, |
||||||
|
channels that receive a GOAWAY when there are no active or pending RPCs should |
||||||
|
also switch to IDLE to avoid connection overload at servers that are attempting |
||||||
|
to shed connections. We will use a default IDLE_TIMEOUT of 300 seconds (5 minutes). |
||||||
|
|
||||||
|
SHUTDOWN: This channel has started shutting down. Any new RPCs should fail |
||||||
|
immediately. Pending RPCs may continue running till the application cancels them. |
||||||
|
Channels may enter this state either because the application explicitly requested |
||||||
|
a shutdown or if a non-recoverable error has happened during attempts to connect |
||||||
|
communicate . (As of 6/12/2015, there are no known errors (while connecting or |
||||||
|
communicating) that are classified as non-recoverable) |
||||||
|
Channels that enter this state never leave this state. |
||||||
|
|
||||||
|
The following table lists the legal transitions from one state to another and |
||||||
|
corresponding reasons. Empty cells denote disallowed transitions. |
||||||
|
|
||||||
|
<table style='border: 1px solid black'> |
||||||
|
<tr> |
||||||
|
<th>From/To</th> |
||||||
|
<th>CONNECTING</th> |
||||||
|
<th>READY</th> |
||||||
|
<th>TRANSIENT_FAILURE</th> |
||||||
|
<th>IDLE</th> |
||||||
|
<th>SHUTDOWN</th> |
||||||
|
</tr> |
||||||
|
<tr> |
||||||
|
<th>CONNECTING</th> |
||||||
|
<td>Incremental progress during connection establishment</td> |
||||||
|
<td>All steps needed to establish a connection succeeded</td> |
||||||
|
<td>Any failure in any of the steps needed to establish connection</td> |
||||||
|
<td>No RPC activity on channel for IDLE_TIMEOUT</td> |
||||||
|
<td>Shutdown triggered by application.</td> |
||||||
|
</tr> |
||||||
|
<tr> |
||||||
|
<th>READY</th> |
||||||
|
<td></td> |
||||||
|
<td>Incremental successful communication on established channel.</td> |
||||||
|
<td>Any failure encountered while expecting successful communication on |
||||||
|
established channel.</td> |
||||||
|
<td>No RPC activity on channel for IDLE_TIMEOUT <br>OR<br>upon receiving a GOAWAY while there are no pending RPCs.</td> |
||||||
|
<td>Shutdown triggered by application.</td> |
||||||
|
</tr> |
||||||
|
<tr> |
||||||
|
<th>TRANSIENT_FAILURE</th> |
||||||
|
<td>Wait time required to implement (exponential) backoff is over.</td> |
||||||
|
<td></td> |
||||||
|
<td></td> |
||||||
|
<td></td> |
||||||
|
<td>Shutdown triggered by application.</td> |
||||||
|
</tr> |
||||||
|
<tr> |
||||||
|
<th>IDLE</th> |
||||||
|
<td>Any new RPC activity on the channel</td> |
||||||
|
<td></td> |
||||||
|
<td></td> |
||||||
|
<td></td> |
||||||
|
<td>Shutdown triggered by application.</td> |
||||||
|
</tr> |
||||||
|
<tr> |
||||||
|
<th>FATAL_FAILURE</th> |
||||||
|
<td></td> |
||||||
|
<td></td> |
||||||
|
<td></td> |
||||||
|
<td></td> |
||||||
|
<td></td> |
||||||
|
</tr> |
||||||
|
</table> |
||||||
|
|
||||||
|
|
||||||
|
Channel State API |
||||||
|
----------------- |
||||||
|
|
||||||
|
All gRPC libraries will expose a channel-level API method to poll the current |
||||||
|
state of a channel. In C++, this method is called GetCurrentState and returns |
||||||
|
an enum for one of the four legal states. |
||||||
|
|
||||||
|
All libraries should also expose an API that enables the application (user of |
||||||
|
the gRPC API) to be notified when the channel state changes. Since state |
||||||
|
changes can be rapid and race with any such notification, the notification |
||||||
|
should just inform the user that some state change has happened, leaving it to |
||||||
|
the user to poll the channel for the current state. |
||||||
|
|
||||||
|
The synchronous version of this API is: |
||||||
|
|
||||||
|
```cpp |
||||||
|
bool WaitForStateChange(gpr_timespec deadline, ChannelState source_state); |
||||||
|
``` |
||||||
|
|
||||||
|
which returns true when the state changes to something other than the |
||||||
|
source_state and false if the deadline expires. Asynchronous and futures based |
||||||
|
APIs should have a corresponding method that allows the application to be |
||||||
|
notified when the state of a channel changes. |
||||||
|
|
||||||
|
Note that a notification is delivered every time there is a transition from any |
||||||
|
state to any *other* state. On the other hand the rules for legal state |
||||||
|
transition, require a transition from CONNECTING to TRANSIENT_FAILURE and back |
||||||
|
to CONNECTING for every recoverable failure, even if the corresponding |
||||||
|
exponential backoff requires no wait before retry. The combined effect is that |
||||||
|
the application may receive state change notifications that appear spurious. |
||||||
|
e.g., an application waiting for state changes on a channel that is CONNECTING |
||||||
|
may receive a state change notification but find the channel in the same |
||||||
|
CONNECTING state on polling for current state because the channel may have |
||||||
|
spent infinitesimally small amount of time in the TRANSIENT_FAILURE state. |
||||||
@ -0,0 +1,72 @@ |
|||||||
|
/*
|
||||||
|
* |
||||||
|
* Copyright 2015, Google Inc. |
||||||
|
* All rights reserved. |
||||||
|
* |
||||||
|
* Redistribution and use in source and binary forms, with or without |
||||||
|
* modification, are permitted provided that the following conditions are |
||||||
|
* met: |
||||||
|
* |
||||||
|
* * Redistributions of source code must retain the above copyright |
||||||
|
* notice, this list of conditions and the following disclaimer. |
||||||
|
* * 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. |
||||||
|
* * Neither the name of Google Inc. nor the names of its |
||||||
|
* contributors may be used to endorse or promote products derived from |
||||||
|
* this software without specific prior written permission. |
||||||
|
* |
||||||
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
||||||
|
* "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 THE COPYRIGHT |
||||||
|
* OWNER 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. |
||||||
|
* |
||||||
|
*/ |
||||||
|
|
||||||
|
#ifndef GRPCXX_CONFIG_PROTOBUF_H |
||||||
|
#define GRPCXX_CONFIG_PROTOBUF_H |
||||||
|
|
||||||
|
#ifndef GRPC_CUSTOM_PROTOBUF_INT64 |
||||||
|
#include <google/protobuf/stubs/common.h> |
||||||
|
#define GRPC_CUSTOM_PROTOBUF_INT64 ::google::protobuf::int64 |
||||||
|
#endif |
||||||
|
|
||||||
|
#ifndef GRPC_CUSTOM_MESSAGE |
||||||
|
#include <google/protobuf/message.h> |
||||||
|
#define GRPC_CUSTOM_MESSAGE ::google::protobuf::Message |
||||||
|
#endif |
||||||
|
|
||||||
|
#ifndef GRPC_CUSTOM_ZEROCOPYOUTPUTSTREAM |
||||||
|
#include <google/protobuf/io/coded_stream.h> |
||||||
|
#include <google/protobuf/io/zero_copy_stream.h> |
||||||
|
#define GRPC_CUSTOM_ZEROCOPYOUTPUTSTREAM \ |
||||||
|
::google::protobuf::io::ZeroCopyOutputStream |
||||||
|
#define GRPC_CUSTOM_ZEROCOPYINPUTSTREAM \ |
||||||
|
::google::protobuf::io::ZeroCopyInputStream |
||||||
|
#define GRPC_CUSTOM_CODEDINPUTSTREAM ::google::protobuf::io::CodedInputStream |
||||||
|
#endif |
||||||
|
|
||||||
|
namespace grpc { |
||||||
|
namespace protobuf { |
||||||
|
|
||||||
|
typedef GRPC_CUSTOM_MESSAGE Message; |
||||||
|
typedef GRPC_CUSTOM_PROTOBUF_INT64 int64; |
||||||
|
|
||||||
|
namespace io { |
||||||
|
typedef GRPC_CUSTOM_ZEROCOPYOUTPUTSTREAM ZeroCopyOutputStream; |
||||||
|
typedef GRPC_CUSTOM_ZEROCOPYINPUTSTREAM ZeroCopyInputStream; |
||||||
|
typedef GRPC_CUSTOM_CODEDINPUTSTREAM CodedInputStream; |
||||||
|
} // namespace io
|
||||||
|
|
||||||
|
} // namespace protobuf
|
||||||
|
} // namespace grpc
|
||||||
|
|
||||||
|
#endif // GRPCXX_CONFIG_PROTOBUF_H
|
||||||
@ -0,0 +1,76 @@ |
|||||||
|
/*
|
||||||
|
* |
||||||
|
* Copyright 2015, Google Inc. |
||||||
|
* All rights reserved. |
||||||
|
* |
||||||
|
* Redistribution and use in source and binary forms, with or without |
||||||
|
* modification, are permitted provided that the following conditions are |
||||||
|
* met: |
||||||
|
* |
||||||
|
* * Redistributions of source code must retain the above copyright |
||||||
|
* notice, this list of conditions and the following disclaimer. |
||||||
|
* * 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. |
||||||
|
* * Neither the name of Google Inc. nor the names of its |
||||||
|
* contributors may be used to endorse or promote products derived from |
||||||
|
* this software without specific prior written permission. |
||||||
|
* |
||||||
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
||||||
|
* "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 THE COPYRIGHT |
||||||
|
* OWNER 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. |
||||||
|
* |
||||||
|
*/ |
||||||
|
|
||||||
|
#ifndef GRPC_INTERNAL_CPP_PROTO_PROTO_UTILS_H |
||||||
|
#define GRPC_INTERNAL_CPP_PROTO_PROTO_UTILS_H |
||||||
|
|
||||||
|
#include <type_traits> |
||||||
|
|
||||||
|
#include <grpc/grpc.h> |
||||||
|
#include <grpc++/impl/serialization_traits.h> |
||||||
|
#include <grpc++/config_protobuf.h> |
||||||
|
#include <grpc++/status.h> |
||||||
|
|
||||||
|
namespace grpc { |
||||||
|
|
||||||
|
// Serialize the msg into a buffer created inside the function. The caller
|
||||||
|
// should destroy the returned buffer when done with it. If serialization fails,
|
||||||
|
// false is returned and buffer is left unchanged.
|
||||||
|
Status SerializeProto(const grpc::protobuf::Message& msg, |
||||||
|
grpc_byte_buffer** buffer); |
||||||
|
|
||||||
|
// The caller keeps ownership of buffer and msg.
|
||||||
|
Status DeserializeProto(grpc_byte_buffer* buffer, grpc::protobuf::Message* msg, |
||||||
|
int max_message_size); |
||||||
|
|
||||||
|
template <class T> |
||||||
|
class SerializationTraits<T, typename std::enable_if<std::is_base_of< |
||||||
|
grpc::protobuf::Message, T>::value>::type> { |
||||||
|
public: |
||||||
|
static Status Serialize(const grpc::protobuf::Message& msg, |
||||||
|
grpc_byte_buffer** buffer, bool* own_buffer) { |
||||||
|
*own_buffer = true; |
||||||
|
return SerializeProto(msg, buffer); |
||||||
|
} |
||||||
|
static Status Deserialize(grpc_byte_buffer* buffer, |
||||||
|
grpc::protobuf::Message* msg, |
||||||
|
int max_message_size) { |
||||||
|
auto status = DeserializeProto(buffer, msg, max_message_size); |
||||||
|
grpc_byte_buffer_destroy(buffer); |
||||||
|
return status; |
||||||
|
} |
||||||
|
}; |
||||||
|
|
||||||
|
} // namespace grpc
|
||||||
|
|
||||||
|
#endif // GRPC_INTERNAL_CPP_PROTO_PROTO_UTILS_H
|
||||||
@ -0,0 +1,68 @@ |
|||||||
|
/*
|
||||||
|
* |
||||||
|
* Copyright 2015, Google Inc. |
||||||
|
* All rights reserved. |
||||||
|
* |
||||||
|
* Redistribution and use in source and binary forms, with or without |
||||||
|
* modification, are permitted provided that the following conditions are |
||||||
|
* met: |
||||||
|
* |
||||||
|
* * Redistributions of source code must retain the above copyright |
||||||
|
* notice, this list of conditions and the following disclaimer. |
||||||
|
* * 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. |
||||||
|
* * Neither the name of Google Inc. nor the names of its |
||||||
|
* contributors may be used to endorse or promote products derived from |
||||||
|
* this software without specific prior written permission. |
||||||
|
* |
||||||
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
||||||
|
* "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 THE COPYRIGHT |
||||||
|
* OWNER 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. |
||||||
|
* |
||||||
|
*/ |
||||||
|
|
||||||
|
#ifndef GRPCXX_IMPL_SERIALIZATION_TRAITS_H |
||||||
|
#define GRPCXX_IMPL_SERIALIZATION_TRAITS_H |
||||||
|
|
||||||
|
namespace grpc { |
||||||
|
|
||||||
|
/// Defines how to serialize and deserialize some type.
|
||||||
|
///
|
||||||
|
/// Used for hooking different message serialization API's into GRPC.
|
||||||
|
/// Each SerializationTraits implementation must provide the following
|
||||||
|
/// functions:
|
||||||
|
/// static Status Serialize(const Message& msg,
|
||||||
|
/// grpc_byte_buffer** buffer,
|
||||||
|
// bool* own_buffer);
|
||||||
|
/// static Status Deserialize(grpc_byte_buffer* buffer,
|
||||||
|
/// Message* msg,
|
||||||
|
/// int max_message_size);
|
||||||
|
///
|
||||||
|
/// Serialize is required to convert message to a grpc_byte_buffer, and
|
||||||
|
/// to store a pointer to that byte buffer at *buffer. *own_buffer should
|
||||||
|
/// be set to true if the caller owns said byte buffer, or false if
|
||||||
|
/// ownership is retained elsewhere.
|
||||||
|
///
|
||||||
|
/// Deserialize is required to convert buffer into the message stored at
|
||||||
|
/// msg. max_message_size is passed in as a bound on the maximum number of
|
||||||
|
/// message bytes Deserialize should accept.
|
||||||
|
///
|
||||||
|
/// Both functions return a Status, allowing them to explain what went
|
||||||
|
/// wrong if required.
|
||||||
|
template <class Message, |
||||||
|
class UnusedButHereForPartialTemplateSpecialization = void> |
||||||
|
class SerializationTraits; |
||||||
|
|
||||||
|
} // namespace grpc
|
||||||
|
|
||||||
|
#endif // GRPCXX_IMPL_SERIALIZATION_TRAITS_H
|
||||||
@ -0,0 +1,61 @@ |
|||||||
|
/*
|
||||||
|
* |
||||||
|
* Copyright 2015, Google Inc. |
||||||
|
* All rights reserved. |
||||||
|
* |
||||||
|
* Redistribution and use in source and binary forms, with or without |
||||||
|
* modification, are permitted provided that the following conditions are |
||||||
|
* met: |
||||||
|
* |
||||||
|
* * Redistributions of source code must retain the above copyright |
||||||
|
* notice, this list of conditions and the following disclaimer. |
||||||
|
* * 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. |
||||||
|
* * Neither the name of Google Inc. nor the names of its |
||||||
|
* contributors may be used to endorse or promote products derived from |
||||||
|
* this software without specific prior written permission. |
||||||
|
* |
||||||
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
||||||
|
* "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 THE COPYRIGHT |
||||||
|
* OWNER 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. |
||||||
|
* |
||||||
|
*/ |
||||||
|
|
||||||
|
#ifndef GRPC_SUPPORT_STRING_UTIL_H |
||||||
|
#define GRPC_SUPPORT_STRING_UTIL_H |
||||||
|
|
||||||
|
#ifdef __cplusplus |
||||||
|
extern "C" { |
||||||
|
#endif |
||||||
|
|
||||||
|
/* String utility functions */ |
||||||
|
|
||||||
|
/* Returns a copy of src that can be passed to gpr_free().
|
||||||
|
If allocation fails or if src is NULL, returns NULL. */ |
||||||
|
char *gpr_strdup(const char *src); |
||||||
|
|
||||||
|
/* printf to a newly-allocated string. The set of supported formats may vary
|
||||||
|
between platforms. |
||||||
|
|
||||||
|
On success, returns the number of bytes printed (excluding the final '\0'), |
||||||
|
and *strp points to a string which must later be destroyed with gpr_free(). |
||||||
|
|
||||||
|
On error, returns -1 and sets *strp to NULL. If the format string is bad, |
||||||
|
the result is undefined. */ |
||||||
|
int gpr_asprintf(char **strp, const char *format, ...); |
||||||
|
|
||||||
|
#ifdef __cplusplus |
||||||
|
} |
||||||
|
#endif |
||||||
|
|
||||||
|
#endif /* GRPC_SUPPORT_STRING_UTIL_H */ |
||||||
Some files were not shown because too many files have changed in this diff Show More
Loading…
Reference in new issue