static void *
clientThread (void *arg)
{
client_t *c = (client_t *) arg;
fd_set rfds, wfds;
int ret;
c->querybuf = sdsMakeRoomFor (sdsempty (), DEFAULT_QUERY_BUF_SIZE);
c->replybuf = sdsMakeRoomFor (sdsempty (), DEFAULT_QUERY_BUF_SIZE);
c->argc = 0;
c->argv = NULL;
c->argvlen = NULL;
c->reqtype = 0;
c->multibulklen = 0;
c->bulklen = -1;
c->rqst = arc_create_request ();
c->flags = 0;
c->total_append_command = 0;
FD_ZERO (&rfds);
FD_ZERO (&wfds);
while (1)
{
struct timeval timeout;
FD_CLR (c->fd, &rfds);
FD_CLR (c->fd, &wfds);
if (!(c->flags & REDIS_CLOSE_AFTER_REPLY))
FD_SET (c->fd, &rfds);
if (sdslen (c->replybuf) > 0)
FD_SET (c->fd, &wfds);
timeout.tv_sec = 1;
timeout.tv_usec = 0;
ret = select (c->fd + 1, &rfds, &wfds, NULL, &timeout);
if (ret == -1)
{
perror ("select");
freeClient (c);
}
if (server.shutdown_signal)
{
c->flags |= REDIS_CLOSE_AFTER_REPLY;
}
/* readable */
if (FD_ISSET (c->fd, &rfds))
{
int pos = sdslen (c->querybuf);
int avail = sdsavail (c->querybuf);
ssize_t nread;
if (avail == 0)
{
c->querybuf =
sdsMakeRoomFor (c->querybuf, sdslen (c->querybuf));
avail = sdsavail (c->querybuf);
}
nread = read (c->fd, c->querybuf + pos, avail);
if (nread > 0)
{
sdsIncrLen (c->querybuf, nread);
processInputBuffer (c);
if (c->total_append_command)
{
int arc_errno, arc_be_errno, be_errno;
arc_ref_t *arc_ref;
arc_ref = acquire_arc_ref ();
ret =
arc_do_request (arc_ref->arc, c->rqst,
server.query_timeout_millis, &be_errno);
if (ret == -1)
{
arc_errno = errno;
arc_be_errno = be_errno;
}
else
{
ret = processReply (c, &be_errno);
if (ret == -1)
{
arc_errno = errno;
arc_be_errno = be_errno;
}
}
arc_free_request (c->rqst);
release_arc_ref (arc_ref);
c->rqst = arc_create_request ();
if (ret == -1)
{
if (arc_errno == ARC_ERR_TIMEOUT
|| (arc_errno == ARC_ERR_BACKEND
&& arc_be_errno == ARC_ERR_TIMEOUT))
{
addReplyStr (c, "-ERR Redis Timeout\r\n");
}
else
{
addReplyStr (c, "-ERR Internal Error\r\n");
}
c->flags |= REDIS_CLOSE_AFTER_REPLY;
}
}
}
else
{
if (nread == -1 && errno == EAGAIN)
{
/* Skip */
}
else
{
freeClient (c);
}
}
}
/* writable */
if (FD_ISSET (c->fd, &wfds))
{
int pos = 0;
int avail = sdslen (c->replybuf);
ssize_t nwritten;
nwritten = write (c->fd, c->replybuf + pos, avail);
if (nwritten > 0)
{
avail -= nwritten;
pos += nwritten;
sdsrange (c->replybuf, pos, -1);
}
else
{
if (nwritten == -1 && errno == EAGAIN)
{
/* Skip */
}
else
{
freeClient (c);
}
}
}
if (sdslen (c->replybuf) == 0 && (c->flags & REDIS_CLOSE_AFTER_REPLY))
{
freeClient (c);
}
}
return NULL;
}
int redisvFormatCommand(char **target, const char *format, va_list ap) {
const char *c = format;
char *cmd = NULL; /* final command */
int pos; /* position in final command */
sds curarg, newarg; /* current argument */
int touched = 0; /* was the current argument touched? */
char **curargv = NULL, **newargv = NULL;
int argc = 0;
int totlen = 0;
int j;
/* Abort if there is not target to set */
if (target == NULL)
return -1;
/* Build the command string accordingly to protocol */
curarg = sdsempty();
if (curarg == NULL)
return -1;
while(*c != '\0') {
if (*c != '%' || c[1] == '\0') {
if (*c == ' ') {
if (touched) {
newargv = realloc(curargv,sizeof(char*)*(argc+1));
if (newargv == NULL) goto err;
curargv = newargv;
curargv[argc++] = curarg;
totlen += bulklen(sdslen(curarg));
/* curarg is put in argv so it can be overwritten. */
curarg = sdsempty();
if (curarg == NULL) goto err;
touched = 0;
}
} else {
newarg = sdscatlen(curarg,c,1);
if (newarg == NULL) goto err;
curarg = newarg;
touched = 1;
}
} else {
char *arg;
size_t size;
/* Set newarg so it can be checked even if it is not touched. */
newarg = curarg;
switch(c[1]) {
case 's':
arg = va_arg(ap,char*);
size = strlen(arg);
if (size > 0)
newarg = sdscatlen(curarg,arg,size);
break;
case 'b':
arg = va_arg(ap,char*);
size = va_arg(ap,size_t);
if (size > 0)
newarg = sdscatlen(curarg,arg,size);
break;
case '%':
newarg = sdscat(curarg,"%");
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++;
}
/* Copy va_list before consuming with va_arg */
va_copy(_cpy,ap);
/* Integer conversion (without modifiers) */
if (strchr("diouxX",*_p) != NULL) {
va_arg(ap,int);
goto fmt_valid;
}
/* Double conversion (without modifiers) */
if (strchr("eEfFgGaA",*_p) != NULL) {
va_arg(ap,double);
goto fmt_valid;
}
/* Size: char */
if (_p[0] == 'h' && _p[1] == 'h') {
_p += 2;
if (*_p != '\0' && strchr("diouxX",*_p) != NULL) {
va_arg(ap,int); /* char gets promoted to int */
goto fmt_valid;
}
goto fmt_invalid;
}
/* Size: short */
if (_p[0] == 'h') {
_p += 1;
if (*_p != '\0' && strchr("diouxX",*_p) != NULL) {
va_arg(ap,int); /* short gets promoted to int */
goto fmt_valid;
}
goto fmt_invalid;
}
/* Size: long long */
if (_p[0] == 'l' && _p[1] == 'l') {
_p += 2;
if (*_p != '\0' && strchr("diouxX",*_p) != NULL) {
va_arg(ap,long long);
goto fmt_valid;
}
goto fmt_invalid;
}
/* Size: long */
if (_p[0] == 'l') {
_p += 1;
if (*_p != '\0' && strchr("diouxX",*_p) != NULL) {
va_arg(ap,long);
goto fmt_valid;
}
goto fmt_invalid;
}
fmt_invalid:
va_end(_cpy);
goto err;
fmt_valid:
_l = (_p+1)-c;
if (_l < sizeof(_format)-2) {
memcpy(_format,c,_l);
_format[_l] = '\0';
newarg = sdscatvprintf(curarg,_format,_cpy);
/* Update current position (note: outer blocks
* increment c twice so compensate here) */
c = _p-1;
}
va_end(_cpy);
break;
}
}
if (newarg == NULL) goto err;
curarg = newarg;
touched = 1;
c++;
}
c++;
}
/* Add the last argument if needed */
if (touched) {
newargv = realloc(curargv,sizeof(char*)*(argc+1));
if (newargv == NULL) goto err;
curargv = newargv;
curargv[argc++] = curarg;
totlen += bulklen(sdslen(curarg));
} else {
sdsfree(curarg);
}
/* Clear curarg because it was put in curargv or was free'd. */
curarg = NULL;
/* 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 == NULL) goto err;
pos = sprintf(cmd,"*%d\r\n",argc);
for (j = 0; j < argc; j++) {
pos += sprintf(cmd+pos,"$%u\r\n",sdslen(curargv[j]));
memcpy(cmd+pos,curargv[j],sdslen(curargv[j]));
pos += sdslen(curargv[j]);
sdsfree(curargv[j]);
cmd[pos++] = '\r';
cmd[pos++] = '\n';
}
assert(pos == totlen);
cmd[pos] = '\0';
free(curargv);
*target = cmd;
return totlen;
err:
while(argc--)
sdsfree(curargv[argc]);
free(curargv);
if (curarg != NULL)
sdsfree(curarg);
/* No need to check cmd since it is the last statement that can fail,
* but do it anyway to be as defensive as possible. */
if (cmd != NULL)
free(cmd);
return -1;
}
static void repl() {
sds historyfile = NULL;
int history = 0;
char *line;
int argc;
sds *argv;
config.interactive = 1;
linenoiseSetCompletionCallback(completionCallback);
/* Only use history when stdin is a tty. */
if (isatty(fileno(stdin))) {
history = 1;
#ifdef _WIN32
if (getenv("USERPROFILE") != NULL) {
historyfile = sdscatprintf(sdsempty(),"%s\\.rediscli_history",getenv("USERPROFILE"));
linenoiseHistoryLoad(historyfile);
}
#else
if (getenv("HOME") != NULL) {
historyfile = sdscatprintf(sdsempty(),"%s/.rediscli_history",getenv("HOME"));
linenoiseHistoryLoad(historyfile);
}
#endif
}
cliRefreshPrompt();
while((line = linenoise(context ? config.prompt : "not connected> ")) != NULL) {
if (line[0] != '\0') {
argv = sdssplitargs(line,&argc);
if (history) linenoiseHistoryAdd(line);
if (historyfile) linenoiseHistorySave(historyfile);
if (argv == NULL) {
printf("Invalid argument(s)\n");
free(line);
continue;
} else if (argc > 0) {
if (strcasecmp(argv[0],"quit") == 0 ||
strcasecmp(argv[0],"exit") == 0)
{
exit(0);
} else if (argc == 3 && !strcasecmp(argv[0],"connect")) {
sdsfree(config.hostip);
config.hostip = sdsnew(argv[1]);
config.hostport = atoi(argv[2]);
cliConnect(1);
} else if (argc == 1 && !strcasecmp(argv[0],"clear")) {
linenoiseClearScreen();
} else {
long long start_time = mstime(), elapsed;
int repeat, skipargs = 0;
repeat = atoi(argv[0]);
if (argc > 1 && repeat) {
skipargs = 1;
} else {
repeat = 1;
}
if (cliSendCommand(argc-skipargs,argv+skipargs,repeat)
!= REDIS_OK)
{
cliConnect(1);
/* If we still cannot send the command print error.
* We'll try to reconnect the next time. */
if (cliSendCommand(argc-skipargs,argv+skipargs,repeat)
!= REDIS_OK)
cliPrintContextError();
}
elapsed = mstime()-start_time;
if (elapsed >= 500) {
printf("(%.2fs)\n",(double)elapsed/1000);
}
}
}
/* Free the argument vector */
while(argc--) sdsfree(argv[argc]);
zfree(argv);
}
/* linenoise() returns malloc-ed lines like readline() */
free(line);
}
exit(0);
}
static sds cliFormatReplyTTY(redisReply *r, char *prefix) {
sds out = sdsempty();
switch (r->type) {
case REDIS_REPLY_ERROR:
out = sdscatprintf(out,"(error) %s\n", r->str);
break;
case REDIS_REPLY_STATUS:
out = sdscat(out,r->str);
out = sdscat(out,"\n");
break;
case REDIS_REPLY_INTEGER:
out = sdscatprintf(out,"(integer) %lld\n",r->integer);
break;
case REDIS_REPLY_STRING:
/* If you are producing output for the standard output we want
* a more interesting output with quoted characters and so forth */
out = sdscatrepr(out,r->str,r->len);
out = sdscat(out,"\n");
break;
case REDIS_REPLY_NIL:
out = sdscat(out,"(nil)\n");
break;
case REDIS_REPLY_ARRAY:
if (r->elements == 0) {
out = sdscat(out,"(empty list or set)\n");
} else {
unsigned int i, idxlen = 0;
char _prefixlen[16];
char _prefixfmt[16];
sds _prefix;
sds tmp;
/* Calculate chars needed to represent the largest index */
i = r->elements;
do {
idxlen++;
i /= 10;
} while(i);
/* Prefix for nested multi bulks should grow with idxlen+2 spaces */
memset(_prefixlen,' ',idxlen+2);
_prefixlen[idxlen+2] = '\0';
_prefix = sdscat(sdsnew(prefix),_prefixlen);
/* Setup prefix format for every entry */
snprintf(_prefixfmt,sizeof(_prefixfmt),"%%s%%%dd) ",idxlen);
for (i = 0; i < r->elements; i++) {
/* Don't use the prefix for the first element, as the parent
* caller already prepended the index number. */
out = sdscatprintf(out,_prefixfmt,i == 0 ? "" : prefix,i+1);
/* Format the multi bulk entry */
tmp = cliFormatReplyTTY(r->element[i],_prefix);
out = sdscatlen(out,tmp,sdslen(tmp));
sdsfree(tmp);
}
sdsfree(_prefix);
}
break;
default:
fprintf(stderr,"Unknown reply type: %d\n", r->type);
exit(1);
}
return out;
}
/* Write the append only file buffer on disk.
*
* Since we are required to write the AOF before replying to the client,
* and the only way the client socket can get a write is entering when the
* the event loop, we accumulate all the AOF writes in a memory
* buffer and write it on disk using this function just before entering
* the event loop again.
*
* About the 'force' argument:
*
* When the fsync policy is set to 'everysec' we may delay the flush if there
* is still an fsync() going on in the background thread, since for instance
* on Linux write(2) will be blocked by the background fsync anyway.
* When this happens we remember that there is some aof buffer to be
* flushed ASAP, and will try to do that in the serverCron() function.
*
* However if force is set to 1 we'll write regardless of the background
* fsync. */
void flushAppendOnlyFile(int force) {
ssize_t nwritten;
int sync_in_progress = 0;
if (sdslen(server.aof_buf) == 0) return;
if (server.aof_fsync == AOF_FSYNC_EVERYSEC)
sync_in_progress = bioPendingJobsOfType(REDIS_BIO_AOF_FSYNC) != 0;
if (server.aof_fsync == AOF_FSYNC_EVERYSEC && !force) {
/* With this append fsync policy we do background fsyncing.
* If the fsync is still in progress we can try to delay
* the write for a couple of seconds. */
if (sync_in_progress) {
if (server.aof_flush_postponed_start == 0) {
/* No previous write postponinig, remember that we are
* postponing the flush and return. */
server.aof_flush_postponed_start = server.unixtime;
return;
} else if (server.unixtime - server.aof_flush_postponed_start < 2) {
/* We were already waiting for fsync to finish, but for less
* than two seconds this is still ok. Postpone again. */
return;
}
/* Otherwise fall trough, and go write since we can't wait
* over two seconds. */
server.aof_delayed_fsync++;
redisLog(REDIS_NOTICE,"Asynchronous AOF fsync is taking too long (disk is busy?). Writing the AOF buffer without waiting for fsync to complete, this may slow down Redis.");
}
}
/* If you are following this code path, then we are going to write so
* set reset the postponed flush sentinel to zero. */
server.aof_flush_postponed_start = 0;
/* We want to perform a single write. This should be guaranteed atomic
* at least if the filesystem we are writing is a real physical one.
* While this will save us against the server being killed I don't think
* there is much to do about the whole server stopping for power problems
* or alike */
nwritten = write(server.aof_fd,server.aof_buf,sdslen(server.aof_buf));
if (nwritten != (signed)sdslen(server.aof_buf)) {
/* Ooops, we are in troubles. The best thing to do for now is
* aborting instead of giving the illusion that everything is
* working as expected. */
if (nwritten == -1) {
redisLog(REDIS_WARNING,"Exiting on error writing to the append-only file: %s",strerror(errno));
} else {
redisLog(REDIS_WARNING,"Exiting on short write while writing to "
"the append-only file: %s (nwritten=%ld, "
"expected=%ld)",
strerror(errno),
(long)nwritten,
(long)sdslen(server.aof_buf));
if (ftruncate(server.aof_fd, server.aof_current_size) == -1) {
redisLog(REDIS_WARNING, "Could not remove short write "
"from the append-only file. Redis may refuse "
"to load the AOF the next time it starts. "
"ftruncate: %s", strerror(errno));
}
}
exit(1);
}
server.aof_current_size += nwritten;
/* Re-use AOF buffer when it is small enough. The maximum comes from the
* arena size of 4k minus some overhead (but is otherwise arbitrary). */
if ((sdslen(server.aof_buf)+sdsavail(server.aof_buf)) < 4000) {
sdsclear(server.aof_buf);
} else {
sdsfree(server.aof_buf);
server.aof_buf = sdsempty();
}
/* Don't fsync if no-appendfsync-on-rewrite is set to yes and there are
* children doing I/O in the background. */
if (server.aof_no_fsync_on_rewrite &&
(server.aof_child_pid != -1 || server.rdb_child_pid != -1))
return;
/* Perform the fsync if needed. */
if (server.aof_fsync == AOF_FSYNC_ALWAYS) {
/* aof_fsync is defined as fdatasync() for Linux in order to avoid
* flushing metadata. */
aof_fsync(server.aof_fd); /* Let's try to get this data on the disk */
server.aof_last_fsync = server.unixtime;
} else if ((server.aof_fsync == AOF_FSYNC_EVERYSEC &&
server.unixtime > server.aof_last_fsync)) {
if (!sync_in_progress) aof_background_fsync(server.aof_fd);
server.aof_last_fsync = server.unixtime;
}
}
/* A background append only file rewriting (BGREWRITEAOF) terminated its work.
* Handle this. */
void backgroundRewriteDoneHandler(int exitcode, int bysignal) {
if (!bysignal && exitcode == 0) {
int newfd, oldfd;
char tmpfile[256];
long long now = ustime();
redisLog(REDIS_NOTICE,
"Background AOF rewrite terminated with success");
/* Flush the differences accumulated by the parent to the
* rewritten AOF. */
snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof",
(int)server.aof_child_pid);
newfd = open(tmpfile,O_WRONLY|O_APPEND);
if (newfd == -1) {
redisLog(REDIS_WARNING,
"Unable to open the temporary AOF produced by the child: %s", strerror(errno));
goto cleanup;
}
if (aofRewriteBufferWrite(newfd) == -1) {
redisLog(REDIS_WARNING,
"Error trying to flush the parent diff to the rewritten AOF: %s", strerror(errno));
close(newfd);
goto cleanup;
}
redisLog(REDIS_NOTICE,
"Parent diff successfully flushed to the rewritten AOF (%lu bytes)", aofRewriteBufferSize());
/* The only remaining thing to do is to rename the temporary file to
* the configured file and switch the file descriptor used to do AOF
* writes. We don't want close(2) or rename(2) calls to block the
* server on old file deletion.
*
* There are two possible scenarios:
*
* 1) AOF is DISABLED and this was a one time rewrite. The temporary
* file will be renamed to the configured file. When this file already
* exists, it will be unlinked, which may block the server.
*
* 2) AOF is ENABLED and the rewritten AOF will immediately start
* receiving writes. After the temporary file is renamed to the
* configured file, the original AOF file descriptor will be closed.
* Since this will be the last reference to that file, closing it
* causes the underlying file to be unlinked, which may block the
* server.
*
* To mitigate the blocking effect of the unlink operation (either
* caused by rename(2) in scenario 1, or by close(2) in scenario 2), we
* use a background thread to take care of this. First, we
* make scenario 1 identical to scenario 2 by opening the target file
* when it exists. The unlink operation after the rename(2) will then
* be executed upon calling close(2) for its descriptor. Everything to
* guarantee atomicity for this switch has already happened by then, so
* we don't care what the outcome or duration of that close operation
* is, as long as the file descriptor is released again. */
if (server.aof_fd == -1) {
/* AOF disabled */
/* Don't care if this fails: oldfd will be -1 and we handle that.
* One notable case of -1 return is if the old file does
* not exist. */
oldfd = open(server.aof_filename,O_RDONLY|O_NONBLOCK);
} else {
/* AOF enabled */
oldfd = -1; /* We'll set this to the current AOF filedes later. */
}
/* Rename the temporary file. This will not unlink the target file if
* it exists, because we reference it with "oldfd". */
if (rename(tmpfile,server.aof_filename) == -1) {
redisLog(REDIS_WARNING,
"Error trying to rename the temporary AOF file: %s", strerror(errno));
close(newfd);
if (oldfd != -1) close(oldfd);
goto cleanup;
}
if (server.aof_fd == -1) {
/* AOF disabled, we don't need to set the AOF file descriptor
* to this new file, so we can close it. */
close(newfd);
} else {
/* AOF enabled, replace the old fd with the new one. */
oldfd = server.aof_fd;
server.aof_fd = newfd;
if (server.aof_fsync == AOF_FSYNC_ALWAYS)
aof_fsync(newfd);
else if (server.aof_fsync == AOF_FSYNC_EVERYSEC)
aof_background_fsync(newfd);
server.aof_selected_db = -1; /* Make sure SELECT is re-issued */
aofUpdateCurrentSize();
server.aof_rewrite_base_size = server.aof_current_size;
/* Clear regular AOF buffer since its contents was just written to
* the new AOF from the background rewrite buffer. */
sdsfree(server.aof_buf);
server.aof_buf = sdsempty();
}
server.aof_lastbgrewrite_status = REDIS_OK;
redisLog(REDIS_NOTICE, "Background AOF rewrite finished successfully");
/* Change state from WAIT_REWRITE to ON if needed */
if (server.aof_state == REDIS_AOF_WAIT_REWRITE)
server.aof_state = REDIS_AOF_ON;
/* Asynchronously close the overwritten AOF. */
if (oldfd != -1) bioCreateBackgroundJob(REDIS_BIO_CLOSE_FILE,(void*)(long)oldfd,NULL,NULL);
redisLog(REDIS_VERBOSE,
"Background AOF rewrite signal handler took %lldus", ustime()-now);
} else if (!bysignal && exitcode != 0) {
server.aof_lastbgrewrite_status = REDIS_ERR;
redisLog(REDIS_WARNING,
"Background AOF rewrite terminated with error");
} else {
server.aof_lastbgrewrite_status = REDIS_ERR;
redisLog(REDIS_WARNING,
"Background AOF rewrite terminated by signal %d", bysignal);
}
cleanup:
aofRewriteBufferReset();
aofRemoveTempFile(server.aof_child_pid);
server.aof_child_pid = -1;
server.aof_rewrite_time_last = time(NULL)-server.aof_rewrite_time_start;
server.aof_rewrite_time_start = -1;
/* Schedule a new rewrite if we are waiting for it to switch the AOF ON. */
if (server.aof_state == REDIS_AOF_WAIT_REWRITE)
server.aof_rewrite_scheduled = 1;
}
static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int argc) {
sds buf = sdsempty();
int j;
ssize_t nwritten;
time_t now;
robj *tmpargv[3];
/* The DB this command was targetting is not the same as the last command
* we appendend. To issue a SELECT command is needed. */
if (dictid != server.appendseldb) {
char seldb[64];
snprintf(seldb,sizeof(seldb),"%d",dictid);
buf = sdscatprintf(buf,"*2\r\n$6\r\nSELECT\r\n$%lu\r\n%s\r\n",
(unsigned long)strlen(seldb), seldb);
server.appendseldb = dictid;
}
/* "Fix" the argv vector if the command is EXPIRE. We want to translate
* EXPIREs into EXPIREATs calls */
if (cmd->proc == expireCommand) {
long when;
tmpargv[0] = createStringObject("EXPIREAT",8);
tmpargv[1] = argv[1];
incrRefCount(argv[1]);
when = time(NULL)+strtol(argv[2]->ptr,NULL,10);
tmpargv[2] = createObject(REDIS_STRING,
sdscatprintf(sdsempty(),"%ld",when));
argv = tmpargv;
}
/* Append the actual command */
buf = sdscatprintf(buf,"*%d\r\n",argc);
for (j = 0; j < argc; j++) {
robj *o = argv[j];
o = getDecodedObject(o);
buf = sdscatprintf(buf,"$%lu\r\n",(unsigned long)sdslen(o->ptr));
buf = sdscatlen(buf,o->ptr,sdslen(o->ptr));
buf = sdscatlen(buf,"\r\n",2);
decrRefCount(o);
}
/* Free the objects from the modified argv for EXPIREAT */
if (cmd->proc == expireCommand) {
for (j = 0; j < 3; j++)
decrRefCount(argv[j]);
}
/* We want to perform a single write. This should be guaranteed atomic
* at least if the filesystem we are writing is a real physical one.
* While this will save us against the server being killed I don't think
* there is much to do about the whole server stopping for power problems
* or alike */
nwritten = write(server.appendfd,buf,sdslen(buf));
/* If a background append only file rewriting is in progress we want to
* accumulate the differences between the child DB and the current one
* in a buffer, so that when the child process will do its work we
* can append the differences to the new append only file. */
if (server.bgrewritechildpid != -1)
server.bgrewritebuf = sdscatlen(server.bgrewritebuf,buf,sdslen(buf));
sdsfree(buf);
now = time(NULL);
if (server.appendfsync == APPENDFSYNC_ALWAYS ||
(server.appendfsync == APPENDFSYNC_EVERYSEC &&
now-server.lastfsync > 1))
{
fsync(server.appendfd); /* Let's try to get this data on the disk */
server.lastfsync = now;
}
}