text: /*
   * Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
   * Copyright (c) 2010-2014, Pieter Noordhuis <pcnoordhuis at gmail dot com>
   * Copyright (c) 2015, Matt Stancliff <matt at genges dot com>,
   *                     Jan-Erik Rediger <janerik at fnordig dot com>
   *
   * 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 Redis 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 __HIREDIS_H
  #define __HIREDIS_H
  #include "read.h"
  #include <stdarg.h> /* for va_list */
  #ifndef _MSC_VER
  #include <sys/time.h> /* for struct timeval */
  #endif
  #include <stdint.h> /* uintXX_t, etc */
  #include "sds.h" /* for sds */
  
  #define HIREDIS_MAJOR 0
  #define HIREDIS_MINOR 13
  #define HIREDIS_PATCH 3
  #define HIREDIS_SONAME 0.13
  
  /* Connection type can be blocking or non-blocking and is set in the
   * least significant bit of the flags field in redisContext. */
  #define REDIS_BLOCK 0x1
  
  /* Connection may be disconnected before being free'd. The second bit
   * in the flags field is set when the context is connected. */
  #define REDIS_CONNECTED 0x2
  
  /* The async API might try to disconnect cleanly and flush the output
   * buffer and read all subsequent replies before disconnecting.
   * This flag means no new commands can come in and the connection
   * should be terminated once all replies have been read. */
  #define REDIS_DISCONNECTING 0x4
  
  /* Flag specific to the async API which means that the context should be clean
   * up as soon as possible. */
  #define REDIS_FREEING 0x8
  
  /* Flag that is set when an async callback is executed. */
  #define REDIS_IN_CALLBACK 0x10
  
  /* Flag that is set when the async context has one or more subscriptions. */
  #define REDIS_SUBSCRIBED 0x20
  
  /* Flag that is set when monitor mode is active */
  #define REDIS_MONITORING 0x40
  
  /* Flag that is set when we should set SO_REUSEADDR before calling bind() */
  #define REDIS_REUSEADDR 0x80
  
  #define REDIS_KEEPALIVE_INTERVAL 15 /* seconds */
  
  /* number of times we retry to connect in the case of EADDRNOTAVAIL and
   * SO_REUSEADDR is being used. */
  #define REDIS_CONNECT_RETRIES  10
  
  /* strerror_r has two completely different prototypes and behaviors
   * depending on system issues, so we need to operate on the error buffer
   * differently depending on which strerror_r we're using. */
  #ifndef _GNU_SOURCE
  /* "regular" POSIX strerror_r that does the right thing. */
  #define __redis_strerror_r(errno, buf, len)                                    \
      do {                                                                       \
          strerror_r((errno), (buf), (len));                                     \
      } while (0)
  #else
  /* "bad" GNU strerror_r we need to clean up after. */
  #define __redis_strerror_r(errno, buf, len)                                    \
      do {                                                                       \
          char *err_str = strerror_r((errno), (buf), (len));                     \
          /* If return value _isn't_ the start of the buffer we passed in,       \
           * then GNU strerror_r returned an internal static buffer and we       \
           * need to copy the result into our private buffer. */                 \
          if (err_str != (buf)) {                                                \
              buf[(len)] = '\0';                                                 \
              strncat((buf), err_str, ((len) - 1));                              \
          }                                                                      \
      } while (0)
  #endif
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /* This is the reply object returned by redisCommand() */
  typedef struct redisReply {
      int type; /* REDIS_REPLY_* */
      long long integer; /* The integer when type is REDIS_REPLY_INTEGER */
      int len; /* Length of string */
      char *str; /* Used for both REDIS_REPLY_ERROR and REDIS_REPLY_STRING */
      size_t elements; /* number of elements, for REDIS_REPLY_ARRAY */
      struct redisReply **element; /* elements vector for REDIS_REPLY_ARRAY */
  } redisReply;
  
  redisReader *redisReaderCreate(void);
  
  /* Function to free the reply objects hiredis returns by default. */
  void freeReplyObject(void *reply);
  
  /* Functions to format a command according to the protocol. */
  int redisvFormatCommand(char **target, const char *format, va_list ap);
  int redisFormatCommand(char **target, const char *format, ...);
  int redisFormatCommandArgv(char **target, int argc, const char **argv, const size_t *argvlen);
  int redisFormatSdsCommandArgv(sds *target, int argc, const char ** argv, const size_t *argvlen);
  void redisFreeCommand(char *cmd);
  void redisFreeSdsCommand(sds cmd);
  
  enum redisConnectionType {
      REDIS_CONN_TCP,
  #ifndef _MSC_VER
      REDIS_CONN_UNIX,
  #endif
  };
  
  /* Context for a connection to Redis */
  typedef struct redisContext {
      int err; /* Error flags, 0 when there is no error */
      char errstr[128]; /* String representation of error when applicable */
      int fd;
      int flags;
      char *obuf; /* Write buffer */
      redisReader *reader; /* Protocol reader */
  
      enum redisConnectionType connection_type;
      struct timeval *timeout;
  
      struct {
          char *host;
          char *source_addr;
          int port;
      } tcp;
  
      struct {
          char *path;
      } unix_sock;
  
  } redisContext;
  
  #ifndef _MSC_VER
  redisContext *redisConnect(const char *ip, int port);
  #endif
  redisContext *redisConnectWithTimeout(const char *ip, int port, const struct timeval tv);
  redisContext *redisConnectNonBlock(const char *ip, int port);
  redisContext *redisConnectBindNonBlock(const char *ip, int port,
                                         const char *source_addr);
  redisContext *redisConnectBindNonBlockWithReuse(const char *ip, int port,
                                                  const char *source_addr);
  #ifndef _MSC_VER
  redisContext *redisConnectUnix(const char *path);
  redisContext *redisConnectUnixWithTimeout(const char *path, const struct timeval tv);
  redisContext *redisConnectUnixNonBlock(const char *path);
  #endif
  redisContext *redisConnectFd(int fd);
  
  /**
   * Reconnect the given context using the saved information.
   *
   * This re-uses the exact same connect options as in the initial connection.
   * host, ip (or path), timeout and bind address are reused,
   * flags are used unmodified from the existing context.
   *
   * Returns REDIS_OK on successfull connect or REDIS_ERR otherwise.
   */
  int redisReconnect(redisContext *c);
  
  int redisSetTimeout(redisContext *c, const struct timeval tv);
  int redisEnableKeepAlive(redisContext *c);
  void redisFree(redisContext *c);
  int redisFreeKeepFd(redisContext *c);
  int redisBufferRead(redisContext *c);
  int redisBufferWrite(redisContext *c, int *done);
  
  /* In a blocking context, this function first checks if there are unconsumed
   * replies to return and returns one if so. Otherwise, it flushes the output
   * buffer to the socket and reads until it has a reply. In a non-blocking
   * context, it will return unconsumed replies until there are no more. */
  int redisGetReply(redisContext *c, void **reply);
  int redisGetReplyFromReader(redisContext *c, void **reply);
  
  /* Write a formatted command to the output buffer. Use these functions in blocking mode
   * to get a pipeline of commands. */
  int redisAppendFormattedCommand(redisContext *c, const char *cmd, size_t len);
  
  /* Write a command to the output buffer. Use these functions in blocking mode
   * to get a pipeline of commands. */
  int redisvAppendCommand(redisContext *c, const char *format, va_list ap);
  int redisAppendCommand(redisContext *c, const char *format, ...);
  int redisAppendCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);
  
  /* Issue a command to Redis. In a blocking context, it is identical to calling
   * redisAppendCommand, followed by redisGetReply. The function will return
   * NULL if there was an error in performing the request, otherwise it will
   * return the reply. In a non-blocking context, it is identical to calling
   * only redisAppendCommand and will always return NULL. */
  void *redisvCommand(redisContext *c, const char *format, va_list ap);
  void *redisCommand(redisContext *c, const char *format, ...);
  void *redisCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif
  