/*
* Copyright (c) 2009-2010, Salvatore Sanfilippo <antirez at gmail dot com>
* Copyright (c) 2010, Pieter Noordhuis <pcnoordhuis at gmail 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.
*/
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <ctype.h>
#include "lib-hiredis.h"
#include "lib-net.h"
#include "lib-sds.h"
#include "lib-util.h"
typedef struct redisReader {
struct redisReplyObjectFunctions *fn;
sds error; /* holds optional error */
void *reply; /* holds temporary reply */
sds buf; /* read buffer */
size_t pos; /* buffer cursor */
size_t len; /* buffer length */
redisReadTask rstack[3]; /* stack of read tasks */
int ridx; /* index of stack */
void *privdata; /* user-settable arbitrary field */
} redisReader;
static redisReply *createReplyObject(int type);
static void *createStringObject(const redisReadTask *task, char *str, size_t len);
static void *createArrayObject(const redisReadTask *task, int elements);
static void *createIntegerObject(const redisReadTask *task, long long value);
static void *createNilObject(const redisReadTask *task);
static void redisSetReplyReaderError(redisReader *r, sds err);
/* Default set of functions to build the reply. */
static redisReplyObjectFunctions defaultFunctions = {
createStringObject,
createArrayObject,
createIntegerObject,
createNilObject,
freeReplyObject
};
/* Create a reply object */
static redisReply *createReplyObject(int type) {
redisReply *r = malloc(sizeof(*r));
if (!r) redisOOM();
r->type = type;
return r;
}
/* Free a reply object */
void freeReplyObject(void *reply) {
redisReply *r = reply;
size_t j;
switch(r->type) {
case REDIS_REPLY_INTEGER:
break; /* Nothing to free */
case REDIS_REPLY_ARRAY:
for (j = 0; j < r->elements; j++)
if (r->element[j]) freeReplyObject(r->element[j]);
free(r->element);
break;
case REDIS_REPLY_ERROR:
case REDIS_REPLY_STATUS:
case REDIS_REPLY_STRING:
free(r->str);
break;
}
free(r);
}
static void *createStringObject(const redisReadTask *task, char *str, size_t len) {
redisReply *r = createReplyObject(task->type);
char *value = malloc(len+1);
if (!value) redisOOM();
assert(task->type == REDIS_REPLY_ERROR ||
task->type == REDIS_REPLY_STATUS ||
task->type == REDIS_REPLY_STRING);
/* Copy string value */
memcpy(value,str,len);
value[len] = '\0';
r->str = value;
r->len = len;
if (task->parent) {
redisReply *parent = task->parent->obj;
assert(parent->type == REDIS_REPLY_ARRAY);
parent->element[task->idx] = r;
}
return r;
}
static void *createArrayObject(const redisReadTask *task, int elements) {
redisReply *r = createReplyObject(REDIS_REPLY_ARRAY);
r->elements = elements;
if ((r->element = calloc(sizeof(redisReply*),elements)) == NULL)
redisOOM();
if (task->parent) {
redisReply *parent = task->parent->obj;
assert(parent->type == REDIS_REPLY_ARRAY);
parent->element[task->idx] = r;
}
return r;
}
static void *createIntegerObject(const redisReadTask *task, long long value) {
redisReply *r = createReplyObject(REDIS_REPLY_INTEGER);
r->integer = value;
if (task->parent) {
redisReply *parent = task->parent->obj;
assert(parent->type == REDIS_REPLY_ARRAY);
parent->element[task->idx] = r;
}
return r;
}
static void *createNilObject(const redisReadTask *task) {
redisReply *r = createReplyObject(REDIS_REPLY_NIL);
if (task->parent) {
redisReply *parent = task->parent->obj;
assert(parent->type == REDIS_REPLY_ARRAY);
parent->element[task->idx] = r;
}
return r;
}
static char *readBytes(redisReader *r, unsigned int bytes) {
char *p;
if (r->len-r->pos >= bytes) {
p = r->buf+r->pos;
r->pos += bytes;
return p;
}
return NULL;
}
/* Find pointer to \r\n. */
static char *seekNewline(char *s, size_t len) {
int pos = 0;
int _len = len-1;
/* Position should be < len-1 because the character at "pos" should be
* followed by a \n. Note that strchr cannot be used because it doesn't
* allow to search a limited length and the buffer that is being searched
* might not have a trailing NULL character. */
while (pos < _len) {
while(pos < _len && s[pos] != '\r') pos++;
if (s[pos] != '\r') {
/* Not found. */
return NULL;
} else {
if (s[pos+1] == '\n') {
/* Found. */
return s+pos;
} else {
/* Continue searching. */
pos++;
}
}
}
return NULL;
}
/* Read a long long value starting at *s, under the assumption that it will be
* terminated by \r\n. Ambiguously returns -1 for unexpected input. */
static long long readLongLong(char *s) {
long long v = 0;
int dec, mult = 1;
char c;
if (*s == '-') {
mult = -1;
s++;
} else if (*s == '+') {
mult = 1;
s++;
}
while ((c = *(s++)) != '\r') {
dec = c - '0';
if (dec >= 0 && dec < 10) {
v *= 10;
v += dec;
} else {
/* Should not happen... */
return -1;
}
}
return mult*v;
}
static char *readLine(redisReader *r, int *_len) {
char *p, *s;
int len;
p = r->buf+r->pos;
s = seekNewline(p,(r->len-r->pos));
if (s != NULL) {
len = s-(r->buf+r->pos);
r->pos += len+2; /* skip \r\n */
if (_len) *_len = len;
return p;
}
return NULL;
}
static void moveToNextTask(redisReader *r) {
redisReadTask *cur, *prv;
while (r->ridx >= 0) {
/* Return a.s.a.p. when the stack is now empty. */
if (r->ridx == 0) {
r->ridx--;
return;
}
cur = &(r->rstack[r->ridx]);
prv = &(r->rstack[r->ridx-1]);
assert(prv->type == REDIS_REPLY_ARRAY);
if (cur->idx == prv->elements-1) {
r->ridx--;
} else {
/* Reset the type because the next item can be anything */
assert(cur->idx < prv->elements);
cur->type = -1;
cur->elements = -1;
cur->idx++;
return;
}
}
}
static int processLineItem(redisReader *r) {
redisReadTask *cur = &(r->rstack[r->ridx]);
void *obj;
char *p;
int len;
if ((p = readLine(r,&len)) != NULL) {
if (r->fn) {
if (cur->type == REDIS_REPLY_INTEGER) {
obj = r->fn->createInteger(cur,readLongLong(p));
} else {
obj = r->fn->createString(cur,p,len);
}
} else {
obj = (void*)(size_t)(cur->type);
}
/* Set reply if this is the root object. */
if (r->ridx == 0) r->reply = obj;
moveToNextTask(r);
return 0;
}
return -1;
}
static int processBulkItem(redisReader *r) {
redisReadTask *cur = &(r->rstack[r->ridx]);
void *obj = NULL;
char *p, *s;
long len;
unsigned long bytelen;
int success = 0;
p = r->buf+r->pos;
s = seekNewline(p,r->len-r->pos);
if (s != NULL) {
p = r->buf+r->pos;
bytelen = s-(r->buf+r->pos)+2; /* include \r\n */
len = readLongLong(p);
if (len < 0) {
/* The nil object can always be created. */
obj = r->fn ? r->fn->createNil(cur) :
(void*)REDIS_REPLY_NIL;
success = 1;
} else {
/* Only continue when the buffer contains the entire bulk item. */
bytelen += len+2; /* include \r\n */
if (r->pos+bytelen <= r->len) {
obj = r->fn ? r->fn->createString(cur,s+2,len) :
(void*)REDIS_REPLY_STRING;
success = 1;
}
}
/* Proceed when obj was created. */
if (success) {
r->pos += bytelen;
/* Set reply if this is the root object. */
if (r->ridx == 0) r->reply = obj;
moveToNextTask(r);
return 0;
}
}
return -1;
}
static int processMultiBulkItem(redisReader *r) {
redisReadTask *cur = &(r->rstack[r->ridx]);
void *obj;
char *p;
long elements;
int root = 0;
/* Set error for nested multi bulks with depth > 1 */
if (r->ridx == 2) {
redisSetReplyReaderError(r,sdscatprintf(sdsempty(),
"No support for nested multi bulk replies with depth > 1"));
return -1;
}
if ((p = readLine(r,NULL)) != NULL) {
elements = readLongLong(p);
root = (r->ridx == 0);
if (elements == -1) {
obj = r->fn ? r->fn->createNil(cur) :
(void*)REDIS_REPLY_NIL;
moveToNextTask(r);
} else {
obj = r->fn ? r->fn->createArray(cur,elements) :
(void*)REDIS_REPLY_ARRAY;
/* Modify task stack when there are more than 0 elements. */
if (elements > 0) {
cur->elements = elements;
cur->obj = obj;
r->ridx++;
r->rstack[r->ridx].type = -1;
r->rstack[r->ridx].elements = -1;
r->rstack[r->ridx].idx = 0;
r->rstack[r->ridx].obj = NULL;
r->rstack[r->ridx].parent = cur;
r->rstack[r->ridx].privdata = r->privdata;
} else {
moveToNextTask(r);
}
}
/* Set reply if this is the root object. */
if (root) r->reply = obj;
return 0;
}
return -1;
}
static int processItem(redisReader *r) {
redisReadTask *cur = &(r->rstack[r->ridx]);
char *p;
sds byte;
/* check if we need to read type */
if (cur->type < 0) {
if ((p = readBytes(r,1)) != NULL) {
switch (p[0]) {
case '-':
cur->type = REDIS_REPLY_ERROR;
break;
case '+':
cur->type = REDIS_REPLY_STATUS;
break;
case ':':
cur->type = REDIS_REPLY_INTEGER;
break;
case '$':
cur->type = REDIS_REPLY_STRING;
break;
case '*':
cur->type = REDIS_REPLY_ARRAY;
break;
default:
byte = sdscatrepr(sdsempty(),p,1);
redisSetReplyReaderError(r,sdscatprintf(sdsempty(),
"Protocol error, got %s as reply type byte", byte));
sdsfree(byte);
return -1;
}
} else {
/* could not consume 1 byte */
return -1;
}
}
/* process typed item */
switch(cur->type) {
case REDIS_REPLY_ERROR:
case REDIS_REPLY_STATUS:
case REDIS_REPLY_INTEGER:
return processLineItem(r);
case REDIS_REPLY_STRING:
return processBulkItem(r);
case REDIS_REPLY_ARRAY:
return processMultiBulkItem(r);
default:
assert(NULL);
return -1;
}
}
void *redisReplyReaderCreate() {
redisReader *r = calloc(sizeof(redisReader),1);
r->error = NULL;
r->fn = &defaultFunctions;
r->buf = sdsempty();
r->ridx = -1;
return r;
}
/* Set the function set to build the reply. Returns REDIS_OK when there
* is no temporary object and it can be set, REDIS_ERR otherwise. */
int redisReplyReaderSetReplyObjectFunctions(void *reader, redisReplyObjectFunctions *fn) {
redisReader *r = reader;
if (r->reply == NULL) {
r->fn = fn;
return REDIS_OK;
}
return REDIS_ERR;
}
/* Set the private data field that is used in the read tasks. This argument can
* be used to curry arbitrary data to the custom reply object functions. */
int redisReplyReaderSetPrivdata(void *reader, void *privdata) {
redisReader *r = reader;
if (r->reply == NULL) {
r->privdata = privdata;
return REDIS_OK;
}
return REDIS_ERR;
}
/* External libraries wrapping hiredis might need access to the temporary
* variable while the reply is built up. When the reader contains an
* object in between receiving some bytes to parse, this object might
* otherwise be free'd by garbage collection. */
void *redisReplyReaderGetObject(void *reader) {
redisReader *r = reader;
return r->reply;
}
void redisReplyReaderFree(void *reader) {
redisReader *r = reader;
if (r->error != NULL)
sdsfree(r->error);
if (r->reply != NULL && r->fn)
r->fn->freeObject(r->reply);
if (r->buf != NULL)
sdsfree(r->buf);
free(r);
}
static void redisSetReplyReaderError(redisReader *r, sds err) {
if (r->reply != NULL)
r->fn->freeObject(r->reply);
/* Clear remaining buffer when we see a protocol error. */
if (r->buf != NULL) {
sdsfree(r->buf);
r->buf = sdsempty();
r->pos = 0;
}
r->ridx = -1;
r->error = err;
}
char *redisReplyReaderGetError(void *reader) {
redisReader *r = reader;
return r->error;
}
void redisReplyReaderFeed(void *reader, char *buf, size_t len) {
redisReader *r = reader;
/* Copy the provided buffer. */
if (buf != NULL && len >= 1) {
r->buf = sdscatlen(r->buf,buf,len);
r->len = sdslen(r->buf);
}
}
int redisReplyReaderGetReply(void *reader, void **reply) {
redisReader *r = reader;
if (reply != NULL) *reply = NULL;
/* When the buffer is empty, there will never be a reply. */
if (r->len == 0)
return REDIS_OK;
/* Set first item to process when the stack is empty. */
if (r->ridx == -1) {
r->rstack[0].type = -1;
r->rstack[0].elements = -1;
r->rstack[0].idx = -1;
r->rstack[0].obj = NULL;
r->rstack[0].parent = NULL;
r->rstack[0].privdata = r->privdata;
r->ridx = 0;
}
/* Process items in reply. */
while (r->ridx >= 0)
if (processItem(r) < 0)
break;
/* Discard the consumed part of the buffer. */
if (r->pos > 0) {
if (r->pos == r->len) {
/* sdsrange has a quirck on this edge case. */
sdsfree(r->buf);
r->buf = sdsempty();
} else {
r->buf = sdsrange(r->buf,r->pos,r->len);
}
r->pos = 0;
r->len = sdslen(r->buf);
}
/* Emit a reply when there is one. */
if (r->ridx == -1) {
void *aux = r->reply;
r->reply = NULL;
/* Destroy the buffer when it is empty and is quite large. */
if (r->len == 0 && sdsavail(r->buf) > 16*1024) {
sdsfree(r->buf);
r->buf = sdsempty();
r->pos = 0;
}
/* Check if there actually *is* a reply. */
if (r->error != NULL) {
return REDIS_ERR;
} else {
if (reply != NULL) *reply = aux;
}
}
return REDIS_OK;
}
/* Calculate the number of bytes needed to represent an integer as string. */
static int intlen(int i) {
int len = 0;
if (i < 0) {
len++;
i = -i;
}
do {
len++;
i /= 10;
} while(i);
return len;
}
/* Helper function for redisvFormatCommand(). */
static void addArgument(sds a, char ***argv, int *argc, int *totlen) {
(*argc)++;
if ((*argv = realloc(*argv, sizeof(char*)*(*argc))) == NULL) redisOOM();
if (totlen) *totlen = *totlen+1+intlen(sdslen(a))+2+sdslen(a)+2;
(*argv)[(*argc)-1] = a;
}
int redisvFormatCommand(char **target, const char *format, va_list ap) {
size_t size;
const char *arg, *c = format;
char *cmd = NULL; /* final command */
int pos; /* position in final command */
sds current; /* current argument */
int interpolated = 0; /* did we do interpolation on an argument? */
char **argv = NULL;
int argc = 0, j;
int totlen = 0;
/* Abort if there is not target to set */
if (target == NULL)
return -1;
/* Build the command string accordingly to protocol */
current = sdsempty();
while(*c != '\0') {
if (*c != '%' || c[1] == '\0') {
if (*c == ' ') {
if (sdslen(current) != 0) {
addArgument(current, &argv, &argc, &totlen);
current = sdsempty();
interpolated = 0;
}
} else {
current = sdscatlen(current,c,1);
}
} else {
switch(c[1]) {
case 's':
arg = va_arg(ap,char*);
size = strlen(arg);
if (size > 0)
current = sdscatlen(current,arg,size);
interpolated = 1;
break;
case 'b':
arg = va_arg(ap,char*);
size = va_arg(ap,size_t);
if (size > 0)
current = sdscatlen(current,arg,size);
interpolated = 1;
break;
case '%':
current = sdscat(current,"%");
break;
default:
/* Try to detect printf format */
{
char _format[16];
const char *_p = c+1;
size_t _l = 0;
va_list _cpy;
/* Flags */
if (*_p != '\0' && *_p == '#') _p++;
if (*_p != '\0' && *_p == '0') _p++;
if (*_p != '\0' && *_p == '-') _p++;
if (*_p != '\0' && *_p == ' ') _p++;
if (*_p != '\0' && *_p == '+') _p++;
/* Field width */
while (*_p != '\0' && isdigit(*_p)) _p++;
/* Precision */
if (*_p == '.') {
_p++;
while (*_p != '\0' && isdigit(*_p)) _p++;
}
/* Modifiers */
if (*_p != '\0') {
if (*_p == 'h' || *_p == 'l') {
/* Allow a single repetition for these modifiers */
if (_p[0] == _p[1]) _p++;
_p++;
}
}
/* Conversion specifier */
if (*_p != '\0' && strchr("diouxXeEfFgGaA",*_p) != NULL) {
_l = (_p+1)-c;
if (_l < sizeof(_format)-2) {
memcpy(_format,c,_l);
_format[_l] = '\0';
va_copy(_cpy,ap);
current = sdscatvprintf(current,_format,_cpy);
interpolated = 1;
va_end(_cpy);
/* Update current position (note: outer blocks
* increment c twice so compensate here) */
c = _p-1;
}
}
/* Consume and discard vararg */
va_arg(ap,void);
}
}
c++;
}
c++;
}
/* Add the last argument if needed */
if (interpolated || sdslen(current) != 0) {
addArgument(current, &argv, &argc, &totlen);
} else {
sdsfree(current);
}
/* Add bytes needed to hold multi bulk count */
totlen += 1+intlen(argc)+2;
/* Build the command at protocol level */
cmd = malloc(totlen+1);
if (!cmd) redisOOM();
pos = sprintf(cmd,"*%d\r\n",argc);
for (j = 0; j < argc; j++) {
pos += sprintf(cmd+pos,"$%zu\r\n",sdslen(argv[j]));
memcpy(cmd+pos,argv[j],sdslen(argv[j]));
pos += sdslen(argv[j]);
sdsfree(argv[j]);
cmd[pos++] = '\r';
cmd[pos++] = '\n';
}
assert(pos == totlen);
free(argv);
cmd[totlen] = '\0';
*target = cmd;
return totlen;
}
/* Format a command according to the Redis protocol. This function
* takes a format similar to printf:
*
* %s represents a C null terminated string you want to interpolate
* %b represents a binary safe string
*
* When using %b you need to provide both the pointer to the string
* and the length in bytes. Examples:
*
* len = redisFormatCommand(target, "GET %s", mykey);
* len = redisFormatCommand(target, "SET %s %b", mykey, myval, myvallen);
*/
int redisFormatCommand(char **target, const char *format, ...) {
va_list ap;
int len;
va_start(ap,format);
len = redisvFormatCommand(target,format,ap);
va_end(ap);
return len;
}
/* Format a command according to the Redis protocol. This function takes the
* number of arguments, an array with arguments and an array with their
* lengths. If the latter is set to NULL, strlen will be used to compute the
* argument lengths.
*/
int redisFormatCommandArgv(char **target, int argc, const char **argv, const size_t *argvlen) {
char *cmd = NULL; /* final command */
int pos; /* position in final command */
size_t len;
int totlen, j;
/* Calculate number of bytes needed for the command */
totlen = 1+intlen(argc)+2;
for (j = 0; j < argc; j++) {
len = argvlen ? argvlen[j] : strlen(argv[j]);
totlen += 1+intlen(len)+2+len+2;
}
/* Build the command at protocol level */
cmd = malloc(totlen+1);
if (!cmd) redisOOM();
pos = sprintf(cmd,"*%d\r\n",argc);
for (j = 0; j < argc; j++) {
len = argvlen ? argvlen[j] : strlen(argv[j]);
pos += sprintf(cmd+pos,"$%zu\r\n",len);
memcpy(cmd+pos,argv[j],len);
pos += len;
cmd[pos++] = '\r';
cmd[pos++] = '\n';
}
assert(pos == totlen);
cmd[totlen] = '\0';
*target = cmd;
return totlen;
}
void __redisSetError(redisContext *c, int type, const sds errstr) {
c->err = type;
if (errstr != NULL) {
c->errstr = errstr;
} else {
/* Only REDIS_ERR_IO may lack a description! */
assert(type == REDIS_ERR_IO);
c->errstr = sdsnew(strerror(errno));
}
}
static redisContext *redisContextInit() {
redisContext *c = calloc(sizeof(redisContext),1);
c->err = 0;
c->errstr = NULL;
c->obuf = sdsempty();
c->fn = &defaultFunctions;
c->reader = NULL;
return c;
}
void redisFree(redisContext *c) {
/* Disconnect before free'ing if not yet disconnected. */
if (c->flags & REDIS_CONNECTED)
close(c->fd);
if (c->errstr != NULL)
sdsfree(c->errstr);
if (c->obuf != NULL)
sdsfree(c->obuf);
if (c->reader != NULL)
redisReplyReaderFree(c->reader);
free(c);
}
/* Connect to a Redis instance. On error the field error in the returned
* context will be set to the return value of the error function.
* When no set of reply functions is given, the default set will be used. */
redisContext *redisConnect(const char *ip, int port) {
redisContext *c = redisContextInit();
c->flags |= REDIS_BLOCK;
redisContextConnectTcp(c,ip,port);
return c;
}
redisContext *redisConnectNonBlock(const char *ip, int port) {
redisContext *c = redisContextInit();
c->flags &= ~REDIS_BLOCK;
redisContextConnectTcp(c,ip,port);
return c;
}
redisContext *redisConnectUnix(const char *path) {
redisContext *c = redisContextInit();
c->flags |= REDIS_BLOCK;
redisContextConnectUnix(c,path);
return c;
}
redisContext *redisConnectUnixNonBlock(const char *path) {
redisContext *c = redisContextInit();
c->flags &= ~REDIS_BLOCK;
redisContextConnectUnix(c,path);
return c;
}
/* Set the replyObjectFunctions to use. Returns REDIS_ERR when the reader
* was already initialized and the function set could not be re-set.
* Return REDIS_OK when they could be set. */
int redisSetReplyObjectFunctions(redisContext *c, redisReplyObjectFunctions *fn) {
if (c->reader != NULL)
return REDIS_ERR;
c->fn = fn;
return REDIS_OK;
}
/* Helper function to lazily create a reply reader. */
static void __redisCreateReplyReader(redisContext *c) {
if (c->reader == NULL) {
c->reader = redisReplyReaderCreate();
assert(redisReplyReaderSetReplyObjectFunctions(c->reader,c->fn) == REDIS_OK);
}
}
/* Use this function to handle a read event on the descriptor. It will try
* and read some bytes from the socket and feed them to the reply parser.
*
* After this function is called, you may use redisContextReadReply to
* see if there is a reply available. */
int redisBufferRead(redisContext *c) {
char buf[2048];
int nread = read(c->fd,buf,sizeof(buf));
if (nread == -1) {
if (errno == EAGAIN) {
/* Try again later */
} else {
__redisSetError(c,REDIS_ERR_IO,NULL);
return REDIS_ERR;
}
} else if (nread == 0) {
__redisSetError(c,REDIS_ERR_EOF,
sdsnew("Server closed the connection"));
return REDIS_ERR;
} else {
__redisCreateReplyReader(c);
redisReplyReaderFeed(c->reader,buf,nread);
}
return REDIS_OK;
}
/* Write the output buffer to the socket.
*
* Returns REDIS_OK when the buffer is empty, or (a part of) the buffer was
* succesfully written to the socket. When the buffer is empty after the
* write operation, "wdone" is set to 1 (if given).
*
* Returns REDIS_ERR if an error occured trying to write and sets
* c->error to hold the appropriate error string.
*/
int redisBufferWrite(redisContext *c, int *done) {
int nwritten;
if (sdslen(c->obuf) > 0) {
nwritten = write(c->fd,c->obuf,sdslen(c->obuf));
if (nwritten == -1) {
if (errno == EAGAIN) {
/* Try again later */
} else {
__redisSetError(c,REDIS_ERR_IO,NULL);
return REDIS_ERR;
}
} else if (nwritten > 0) {
if (nwritten == (signed)sdslen(c->obuf)) {
sdsfree(c->obuf);
c->obuf = sdsempty();
} else {
c->obuf = sdsrange(c->obuf,nwritten,-1);
}
}
}
if (done != NULL) *done = (sdslen(c->obuf) == 0);
return REDIS_OK;
}
/* Internal helper function to try and get a reply from the reader,
* or set an error in the context otherwise. */
int redisGetReplyFromReader(redisContext *c, void **reply) {
__redisCreateReplyReader(c);
if (redisReplyReaderGetReply(c->reader,reply) == REDIS_ERR) {
__redisSetError(c,REDIS_ERR_PROTOCOL,
sdsnew(((redisReader*)c->reader)->error));
return REDIS_ERR;
}
return REDIS_OK;
}
int redisGetReply(redisContext *c, void **reply) {
int wdone = 0;
void *aux = NULL;
/* Try to read pending replies */
if (redisGetReplyFromReader(c,&aux) == REDIS_ERR)
return REDIS_ERR;
/* For the blocking context, flush output buffer and read reply */
if (aux == NULL && c->flags & REDIS_BLOCK) {
/* Write until done */
do {
if (redisBufferWrite(c,&wdone) == REDIS_ERR)
return REDIS_ERR;
} while (!wdone);
/* Read until there is a reply */
do {
if (redisBufferRead(c) == REDIS_ERR)
return REDIS_ERR;
if (redisGetReplyFromReader(c,&aux) == REDIS_ERR)
return REDIS_ERR;
} while (aux == NULL);
}
/* Set reply object */
if (reply != NULL) *reply = aux;
return REDIS_OK;
}
/* Helper function for the redisAppendCommand* family of functions.
*
* Write a formatted command to the output buffer. When this family
* is used, you need to call redisGetReply yourself to retrieve
* the reply (or replies in pub/sub).
*/
void __redisAppendCommand(redisContext *c, char *cmd, size_t len) {
c->obuf = sdscatlen(c->obuf,cmd,len);
}
void redisvAppendCommand(redisContext *c, const char *format, va_list ap) {
char *cmd;
int len;
len = redisvFormatCommand(&cmd,format,ap);
__redisAppendCommand(c,cmd,len);
free(cmd);
}
void redisAppendCommand(redisContext *c, const char *format, ...) {
va_list ap;
va_start(ap,format);
redisvAppendCommand(c,format,ap);
va_end(ap);
}
void redisAppendCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen) {
char *cmd;
int len;
len = redisFormatCommandArgv(&cmd,argc,argv,argvlen);
__redisAppendCommand(c,cmd,len);
free(cmd);
}
/* Helper function for the redisCommand* family of functions.
*
* Write a formatted command to the output buffer. If the given context is
* blocking, immediately read the reply into the "reply" pointer. When the
* context is non-blocking, the "reply" pointer will not be used and the
* command is simply appended to the write buffer.
*
* Returns the reply when a reply was succesfully retrieved. Returns NULL
* otherwise. When NULL is returned in a blocking context, the error field
* in the context will be set.
*/
static void *__redisCommand(redisContext *c, char *cmd, size_t len) {
void *aux = NULL;
__redisAppendCommand(c,cmd,len);
if (c->flags & REDIS_BLOCK) {
if (redisGetReply(c,&aux) == REDIS_OK)
return aux;
return NULL;
}
return NULL;
}
void *redisvCommand(redisContext *c, const char *format, va_list ap) {
char *cmd;
int len;
void *reply = NULL;
len = redisvFormatCommand(&cmd,format,ap);
reply = __redisCommand(c,cmd,len);
free(cmd);
return reply;
}
void *redisCommand(redisContext *c, const char *format, ...) {
va_list ap;
void *reply = NULL;
va_start(ap,format);
reply = redisvCommand(c,format,ap);
va_end(ap);
return reply;
}
void *redisCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen) {
char *cmd;
int len;
void *reply = NULL;
len = redisFormatCommandArgv(&cmd,argc,argv,argvlen);
reply = __redisCommand(c,cmd,len);
free(cmd);
return reply;
}