/*
* Copyright (c) 2009-2011, Salvatore Sanfilippo <antirez at gmail dot com>
* Copyright (c) 2010-2011, 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 "fmacros.h"
#include <string.h>
#include <stdlib.h>
#ifndef _MSC_VER
#include <unistd.h>
#endif
#include <assert.h>
#include <errno.h>
#include <ctype.h>
#include "read.h"
#include "sds.h"
static void __redisReaderSetError(redisReader *r, int type, const char *str) {
size_t len;
if (r->reply != NULL && r->fn && r->fn->freeObject) {
r->fn->freeObject(r->reply);
r->reply = NULL;
}
/* Clear input buffer on errors. */
if (r->buf != NULL) {
sdsfree(r->buf);
r->buf = NULL;
r->pos = r->len = 0;
}
/* Reset task stack. */
r->ridx = -1;
/* Set error. */
r->err = type;
len = strlen(str);
len = len < (sizeof(r->errstr)-1) ? len : (sizeof(r->errstr)-1);
memcpy(r->errstr,str,len);
r->errstr[len] = '\0';
}
static size_t chrtos(char *buf, size_t size, char byte) {
size_t len = 0;
switch(byte) {
case '\\':
case '"':
len = snprintf(buf,size,"\"\\%c\"",byte);
break;
case '\n': len = snprintf(buf,size,"\"\\n\""); break;
case '\r': len = snprintf(buf,size,"\"\\r\""); break;
case '\t': len = snprintf(buf,size,"\"\\t\""); break;
case '\a': len = snprintf(buf,size,"\"\\a\""); break;
case '\b': len = snprintf(buf,size,"\"\\b\""); break;
default:
if (isprint(byte))
len = snprintf(buf,size,"\"%c\"",byte);
else
len = snprintf(buf,size,"\"\\x%02x\"",(unsigned char)byte);
break;
}
return len;
}
static void __redisReaderSetErrorProtocolByte(redisReader *r, char byte) {
char cbuf[8], sbuf[128];
chrtos(cbuf,sizeof(cbuf),byte);
snprintf(sbuf,sizeof(sbuf),
"Protocol error, got %s as reply type byte", cbuf);
__redisReaderSetError(r,REDIS_ERR_PROTOCOL,sbuf);
}
static void __redisReaderSetErrorOOM(redisReader *r) {
__redisReaderSetError(r,REDIS_ERR_OOM,"Out of memory");
}
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 (cur->type == REDIS_REPLY_INTEGER) {
if (r->fn && r->fn->createInteger)
obj = r->fn->createInteger(cur,readLongLong(p));
else
obj = (void*)REDIS_REPLY_INTEGER;
} else {
/* Type will be error or status. */
if (r->fn && r->fn->createString)
obj = r->fn->createString(cur,p,len);
else
obj = (void*)(size_t)(cur->type);
}
if (obj == NULL) {
__redisReaderSetErrorOOM(r);
return REDIS_ERR;
}
/* Set reply if this is the root object. */
if (r->ridx == 0) r->reply = obj;
moveToNextTask(r);
return REDIS_OK;
}
return REDIS_ERR;
}
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. */
if (r->fn && r->fn->createNil)
obj = r->fn->createNil(cur);
else
obj = (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) {
if (r->fn && r->fn->createString)
obj = r->fn->createString(cur,s+2,len);
else
obj = (void*)REDIS_REPLY_STRING;
success = 1;
}
}
/* Proceed when obj was created. */
if (success) {
if (obj == NULL) {
__redisReaderSetErrorOOM(r);
return REDIS_ERR;
}
r->pos += bytelen;
/* Set reply if this is the root object. */
if (r->ridx == 0) r->reply = obj;
moveToNextTask(r);
return REDIS_OK;
}
}
return REDIS_ERR;
}
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 > 7 */
if (r->ridx == 8) {
__redisReaderSetError(r,REDIS_ERR_PROTOCOL,
"No support for nested multi bulk replies with depth > 7");
return REDIS_ERR;
}
if ((p = readLine(r,NULL)) != NULL) {
elements = readLongLong(p);
root = (r->ridx == 0);
if (elements == -1) {
if (r->fn && r->fn->createNil)
obj = r->fn->createNil(cur);
else
obj = (void*)REDIS_REPLY_NIL;
if (obj == NULL) {
__redisReaderSetErrorOOM(r);
return REDIS_ERR;
}
moveToNextTask(r);
} else {
if (r->fn && r->fn->createArray)
obj = r->fn->createArray(cur,elements);
else
obj = (void*)REDIS_REPLY_ARRAY;
if (obj == NULL) {
__redisReaderSetErrorOOM(r);
return REDIS_ERR;
}
/* 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 REDIS_OK;
}
return REDIS_ERR;
}
static int processItem(redisReader *r) {
redisReadTask *cur = &(r->rstack[r->ridx]);
char *p;
/* 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:
__redisReaderSetErrorProtocolByte(r,*p);
return REDIS_ERR;
}
} else {
/* could not consume 1 byte */
return REDIS_ERR;
}
}
/* 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 REDIS_ERR; /* Avoid warning. */
}
}
redisReader *redisReaderCreateWithFunctions(redisReplyObjectFunctions *fn) {
redisReader *r;
r = calloc(sizeof(redisReader),1);
if (r == NULL)
return NULL;
r->err = 0;
r->errstr[0] = '\0';
r->fn = fn;
r->buf = sdsempty();
r->maxbuf = REDIS_READER_MAX_BUF;
if (r->buf == NULL) {
free(r);
return NULL;
}
r->ridx = -1;
return r;
}
void redisReaderFree(redisReader *r) {
if (r->reply != NULL && r->fn && r->fn->freeObject)
r->fn->freeObject(r->reply);
if (r->buf != NULL)
sdsfree(r->buf);
free(r);
}
int redisReaderFeed(redisReader *r, const char *buf, size_t len) {
sds newbuf;
/* Return early when this reader is in an erroneous state. */
if (r->err)
return REDIS_ERR;
/* Copy the provided buffer. */
if (buf != NULL && len >= 1) {
/* Destroy internal buffer when it is empty and is quite large. */
if (r->len == 0 && r->maxbuf != 0 && sdsavail(r->buf) > r->maxbuf) {
sdsfree(r->buf);
r->buf = sdsempty();
r->pos = 0;
/* r->buf should not be NULL since we just free'd a larger one. */
assert(r->buf != NULL);
}
newbuf = sdscatlen(r->buf,buf,len);
if (newbuf == NULL) {
__redisReaderSetErrorOOM(r);
return REDIS_ERR;
}
r->buf = newbuf;
r->len = sdslen(r->buf);
}
return REDIS_OK;
}
int redisReaderGetReply(redisReader *r, void **reply) {
/* Default target pointer to NULL. */
if (reply != NULL)
*reply = NULL;
/* Return early when this reader is in an erroneous state. */
if (r->err)
return REDIS_ERR;
/* 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) != REDIS_OK)
break;
/* Return ASAP when an error occurred. */
if (r->err)
return REDIS_ERR;
/* Discard part of the buffer when we've consumed at least 1k, to avoid
* doing unnecessary calls to memmove() in sds.c. */
if (r->pos >= 1024) {
sdsrange(r->buf,r->pos,-1);
r->pos = 0;
r->len = sdslen(r->buf);
}
/* Emit a reply when there is one. */
if (r->ridx == -1) {
if (reply != NULL)
*reply = r->reply;
r->reply = NULL;
}
return REDIS_OK;
}