X-Git-Url: https://git.octo.it/?p=rrdtool.git;a=blobdiff_plain;f=src%2Frrd_client.c;h=21139f0ba3be7b772fc00001239d841fb136fa0c;hp=287f642db4754253eba0134679bf1e650f60ad45;hb=96b0f4aace0deef034a792a08dc2d426cd2b61a4;hpb=6f5e93c0c08c5ed796d8d079f0eba2d16c6a4bdb

diff --git a/src/rrd_client.c b/src/rrd_client.c
index 287f642..21139f0 100644
--- a/src/rrd_client.c
+++ b/src/rrd_client.c
@@ -1,19 +1,24 @@
 /**
  * RRDTool - src/rrd_client.c
- * Copyright (C) 2008 Florian octo Forster
+ * Copyright (C) 2008-2010  Florian octo Forster
  *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; only version 2 of the License is applicable.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
  *
  * Authors:
  *   Florian octo Forster <octo at verplant.org>
@@ -21,11 +26,13 @@
  **/
 
 #include "rrd.h"
-#include "rrd_client.h"
 #include "rrd_tool.h"
+#include "rrd_client.h"
 
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <strings.h>
 #include <errno.h>
 #include <assert.h>
 #include <pthread.h>
@@ -33,6 +40,7 @@
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <netdb.h>
+#include <limits.h>
 
 #ifndef ENODATA
 #define ENODATA ENOENT
@@ -65,31 +73,163 @@ static const char *get_path (const char *path, char *resolved_path) /* {{{ */
   const char *ret = path;
   int is_unix = 0;
 
+  if ((path == NULL) || (resolved_path == NULL) || (sd_path == NULL))
+    return (NULL);
+
   if ((*sd_path == '/')
       || (strncmp ("unix:", sd_path, strlen ("unix:")) == 0))
     is_unix = 1;
 
-  if (*path == '/') /* absolute path */
+  if (is_unix)
+  {
+    ret = realpath(path, resolved_path);
+    if (ret == NULL)
+      rrd_set_error("realpath(%s): %s", path, rrd_strerror(errno));
+    return ret;
+  }
+  else
   {
-    if (! is_unix)
+    if (*path == '/') /* not absolute path */
     {
       rrd_set_error ("absolute path names not allowed when talking "
           "to a remote daemon");
-      return (NULL);
+      return NULL;
     }
-    /* else: nothing to do */
   }
-  else /* relative path */
+
+  return path;
+} /* }}} char *get_path */
+
+static size_t strsplit (char *string, char **fields, size_t size) /* {{{ */
+{
+  size_t i;
+  char *ptr;
+  char *saveptr;
+
+  i = 0;
+  ptr = string;
+  saveptr = NULL;
+  while ((fields[i] = strtok_r (ptr, " \t\r\n", &saveptr)) != NULL)
   {
-    if (is_unix)
-    {
-      realpath (path, resolved_path);
-      ret = resolved_path;
-    }
-    /* else: nothing to do */
+    ptr = NULL;
+    i++;
+
+    if (i >= size)
+      break;
   }
-  return (ret);
-} /* }}} char *get_path */
+
+  return (i);
+} /* }}} size_t strsplit */
+
+static int parse_header (char *line, /* {{{ */
+    char **ret_key, char **ret_value)
+{
+  char *tmp;
+
+  *ret_key = line;
+
+  tmp = strchr (line, ':');
+  if (tmp == NULL)
+    return (-1);
+
+  do
+  {
+    *tmp = 0;
+    tmp++;
+  }
+  while ((tmp[0] == ' ') || (tmp[0] == '\t'));
+
+  if (*tmp == 0)
+    return (-1);
+
+  *ret_value = tmp;
+  return (0);
+} /* }}} int parse_header */
+
+static int parse_ulong_header (char *line, /* {{{ */
+    char **ret_key, unsigned long *ret_value)
+{
+  char *str_value;
+  char *endptr;
+  int status;
+
+  str_value = NULL;
+  status = parse_header (line, ret_key, &str_value);
+  if (status != 0)
+    return (status);
+
+  endptr = NULL;
+  errno = 0;
+  *ret_value = (unsigned long) strtol (str_value, &endptr, /* base = */ 0);
+  if ((endptr == str_value) || (errno != 0))
+    return (-1);
+
+  return (0);
+} /* }}} int parse_ulong_header */
+
+static int parse_char_array_header (char *line, /* {{{ */
+    char **ret_key, char **array, size_t array_len, int alloc)
+{
+  char *tmp_array[array_len];
+  char *value;
+  size_t num;
+  int status;
+
+  value = NULL;
+  status = parse_header (line, ret_key, &value);
+  if (status != 0)
+    return (-1);
+
+  num = strsplit (value, tmp_array, array_len);
+  if (num != array_len)
+    return (-1);
+
+  if (alloc == 0)
+  {
+    memcpy (array, tmp_array, sizeof (tmp_array));
+  }
+  else
+  {
+    size_t i;
+
+    for (i = 0; i < array_len; i++)
+      array[i] = strdup (tmp_array[i]);
+  }
+
+  return (0);
+} /* }}} int parse_char_array_header */
+
+static int parse_value_array_header (char *line, /* {{{ */
+    time_t *ret_time, rrd_value_t *array, size_t array_len)
+{
+  char *str_key;
+  char *str_array[array_len];
+  char *endptr;
+  int status;
+  size_t i;
+
+  str_key = NULL;
+  status = parse_char_array_header (line, &str_key,
+      str_array, array_len, /* alloc = */ 0);
+  if (status != 0)
+    return (-1);
+
+  errno = 0;
+  endptr = NULL;
+  *ret_time = (time_t) strtol (str_key, &endptr, /* base = */ 10);
+  if ((endptr == str_key) || (errno != 0))
+    return (-1);
+
+  for (i = 0; i < array_len; i++)
+  {
+    endptr = NULL;
+    array[i] = (rrd_value_t) strtod (str_array[i], &endptr);
+    if ((endptr == str_array[i]) || (errno != 0))
+      return (-1);
+  }
+
+  return (0);
+} /* }}} int parse_value_array_header */
 
 /* One must hold `lock' when calling `close_connection'. */
 static void close_connection (void) /* {{{ */
@@ -176,6 +316,16 @@ static int buffer_add_value (const char *value, /* {{{ */
   return (buffer_add_string (temp, buffer_ret, buffer_size_ret));
 } /* }}} int buffer_add_value */
 
+static int buffer_add_ulong (const unsigned long value, /* {{{ */
+    char **buffer_ret, size_t *buffer_size_ret)
+{
+  char temp[4096];
+
+  snprintf (temp, sizeof (temp), "%lu", value);
+  temp[sizeof (temp) - 1] = 0;
+  return (buffer_add_string (temp, buffer_ret, buffer_size_ret));
+} /* }}} int buffer_add_ulong */
+
 /* Remove trailing newline (NL) and carriage return (CR) characters. Similar to
  * the Perl function `chomp'. Returns the number of characters that have been
  * removed. */
@@ -219,34 +369,36 @@ static void response_free (rrdc_response_t *res) /* {{{ */
 
 static int response_read (rrdc_response_t **ret_response) /* {{{ */
 {
-  rrdc_response_t *ret;
+  rrdc_response_t *ret = NULL;
+  int status = 0;
 
   char buffer[4096];
   char *buffer_ptr;
 
   size_t i;
 
+#define DIE(code) do { status = code; goto err_out; } while(0)
+
   if (sh == NULL)
-    return (-1);
+    DIE(-1);
 
   ret = (rrdc_response_t *) malloc (sizeof (rrdc_response_t));
   if (ret == NULL)
-    return (-2);
+    DIE(-2);
   memset (ret, 0, sizeof (*ret));
   ret->lines = NULL;
   ret->lines_num = 0;
 
   buffer_ptr = fgets (buffer, sizeof (buffer), sh);
   if (buffer_ptr == NULL)
-    return (-3);
+    DIE(-3);
+
   chomp (buffer);
 
   ret->status = strtol (buffer, &ret->message, 0);
   if (buffer == ret->message)
-  {
-    response_free (ret);
-    return (-4);
-  }
+    DIE(-4);
+
   /* Skip leading whitespace of the status message */
   ret->message += strspn (ret->message, " \t");
 
@@ -254,16 +406,13 @@ static int response_read (rrdc_response_t **ret_response) /* {{{ */
   {
     if (ret->status < 0)
       rrd_set_error("rrdcached: %s", ret->message);
-    *ret_response = ret;
-    return (0);
+    goto out;
   }
 
   ret->lines = (char **) malloc (sizeof (char *) * ret->status);
   if (ret->lines == NULL)
-  {
-    response_free (ret);
-    return (-5);
-  }
+    DIE(-5);
+
   memset (ret->lines, 0, sizeof (char *) * ret->status);
   ret->lines_num = (size_t) ret->status;
 
@@ -271,22 +420,27 @@ static int response_read (rrdc_response_t **ret_response) /* {{{ */
   {
     buffer_ptr = fgets (buffer, sizeof (buffer), sh);
     if (buffer_ptr == NULL)
-    {
-      response_free (ret);
-      return (-6);
-    }
+      DIE(-6);
+
     chomp (buffer);
 
     ret->lines[i] = strdup (buffer);
     if (ret->lines[i] == NULL)
-    {
-      response_free (ret);
-      return (-7);
-    }
+      DIE(-7);
   }
 
+out:
   *ret_response = ret;
-  return (0);
+  fflush(sh);
+  return (status);
+
+err_out:
+  response_free(ret);
+  close_connection();
+  return (status);
+
+#undef DIE
+
 } /* }}} rrdc_response_t *response_read */
 
 static int request (const char *buffer, size_t buffer_size, /* {{{ */
@@ -436,8 +590,8 @@ static int rrdc_connect_network (const char *addr_orig) /* {{{ */
       rrd_set_error("garbage after address: %s", port);
       return (-1);
     }
-  } /* if (*addr = ']') */
-  else if (strchr (addr, '.') != NULL) /* Hostname or IPv4 */
+  } /* if (*addr == '[') */
+  else
   {
     port = rindex(addr, ':');
     if (port != NULL)
@@ -671,6 +825,529 @@ int rrdc_flush (const char *filename) /* {{{ */
   return (status);
 } /* }}} int rrdc_flush */
 
+rrd_info_t * rrdc_info (const char *filename) /* {{{ */
+{
+  char buffer[4096];
+  char *buffer_ptr;
+  size_t buffer_free;
+  size_t buffer_size;
+  rrdc_response_t *res;
+  int status;
+  char file_path[PATH_MAX];
+  rrd_info_t *data = NULL, *cd;
+  rrd_infoval_t info;
+  unsigned int l;
+  rrd_info_type_t itype;
+  char *k, *s;
+
+  if (filename == NULL) {
+    rrd_set_error ("rrdc_info: no filename");
+    return (NULL);
+  }
+
+  memset (buffer, 0, sizeof (buffer));
+  buffer_ptr = &buffer[0];
+  buffer_free = sizeof (buffer);
+
+  status = buffer_add_string ("info", &buffer_ptr, &buffer_free);
+  if (status != 0) {
+    rrd_set_error ("rrdc_info: out of memory");
+    return (NULL);
+  }
+
+  pthread_mutex_lock (&lock);
+  filename = get_path (filename, file_path);
+  if (filename == NULL)
+  {
+    pthread_mutex_unlock (&lock);
+    return (NULL);
+  }
+
+  status = buffer_add_string (filename, &buffer_ptr, &buffer_free);
+  if (status != 0)
+  {
+    pthread_mutex_unlock (&lock);
+    rrd_set_error ("rrdc_info: out of memory");
+    return (NULL);
+  }
+
+  assert (buffer_free < sizeof (buffer));
+  buffer_size = sizeof (buffer) - buffer_free;
+  assert (buffer[buffer_size - 1] == ' ');
+  buffer[buffer_size - 1] = '\n';
+
+  res = NULL;
+  status = request (buffer, buffer_size, &res);
+  pthread_mutex_unlock (&lock);
+
+  if (status != 0) {
+    rrd_set_error ("rrdcached: %s", res->message);
+    return (NULL);
+  }
+  data = cd = NULL;
+  for( l=0 ; l < res->lines_num ; l++ ) {
+    /* first extract the keyword */
+	for(k = s = res->lines[l];s && *s;s++) {
+      if(*s == ' ') { *s = 0; s++; break; }
+	}
+    if(!s || !*s) break;
+	itype = atoi(s); /* extract type code */
+	for(;*s;s++) { if(*s == ' ') { *s = 0; s++; break; } }
+    if(!*s) break;
+    /* finally, we're pointing to the value */
+    switch(itype) {
+    case RD_I_VAL:
+        if(*s == 'N') { info.u_val = DNAN; } else { info.u_val = atof(s); }
+        break;
+    case RD_I_CNT:
+        info.u_cnt = atol(s);
+        break;
+    case RD_I_INT:
+        info.u_int = atoi(s);
+        break;
+    case RD_I_STR:
+        chomp(s);
+        info.u_str = (char*)malloc(sizeof(char) * (strlen(s) + 1));
+        strcpy(info.u_str,s);
+        break;
+    case RD_I_BLO:
+        rrd_set_error ("rrdc_info: BLOB objects are not supported");
+        return (NULL);
+    default:
+        rrd_set_error ("rrdc_info: Unsupported info type %d",itype);
+        return (NULL);
+    }
+	
+    cd = rrd_info_push(cd, sprintf_alloc("%s",k), itype, info);
+	if(!data) data = cd;
+  }
+  response_free (res);
+
+  return (data);
+} /* }}} int rrdc_info */
+
+time_t rrdc_last (const char *filename) /* {{{ */
+{
+  char buffer[4096];
+  char *buffer_ptr;
+  size_t buffer_free;
+  size_t buffer_size;
+  rrdc_response_t *res;
+  int status;
+  char file_path[PATH_MAX];
+  time_t lastup;
+
+  if (filename == NULL) {
+    rrd_set_error ("rrdc_last: no filename");
+    return (-1);
+  }
+
+  memset (buffer, 0, sizeof (buffer));
+  buffer_ptr = &buffer[0];
+  buffer_free = sizeof (buffer);
+
+  status = buffer_add_string ("last", &buffer_ptr, &buffer_free);
+  if (status != 0) {
+    rrd_set_error ("rrdc_last: out of memory");
+    return (-1);
+  }
+
+  pthread_mutex_lock (&lock);
+  filename = get_path (filename, file_path);
+  if (filename == NULL)
+  {
+    pthread_mutex_unlock (&lock);
+    return (-1);
+  }
+
+  status = buffer_add_string (filename, &buffer_ptr, &buffer_free);
+  if (status != 0)
+  {
+    pthread_mutex_unlock (&lock);
+    rrd_set_error ("rrdc_last: out of memory");
+    return (-1);
+  }
+
+  assert (buffer_free < sizeof (buffer));
+  buffer_size = sizeof (buffer) - buffer_free;
+  assert (buffer[buffer_size - 1] == ' ');
+  buffer[buffer_size - 1] = '\n';
+
+  res = NULL;
+  status = request (buffer, buffer_size, &res);
+  pthread_mutex_unlock (&lock);
+
+  if (status != 0) {
+    rrd_set_error ("rrdcached: %s", res->message);
+    return (-1);
+  }
+  lastup = atol(res->message);
+  response_free (res);
+
+  return (lastup);
+} /* }}} int rrdc_last */
+
+time_t rrdc_first (const char *filename, int rraindex) /* {{{ */
+{
+  char buffer[4096];
+  char *buffer_ptr;
+  size_t buffer_free;
+  size_t buffer_size;
+  rrdc_response_t *res;
+  int status;
+  char file_path[PATH_MAX];
+  time_t firstup;
+
+  if (filename == NULL) {
+    rrd_set_error ("rrdc_first: no filename specified");
+    return (-1);
+  }
+
+  memset (buffer, 0, sizeof (buffer));
+  buffer_ptr = &buffer[0];
+  buffer_free = sizeof (buffer);
+
+  status = buffer_add_string ("first", &buffer_ptr, &buffer_free);
+  if (status != 0) {
+    rrd_set_error ("rrdc_first: out of memory");
+    return (-1);
+  }
+
+  pthread_mutex_lock (&lock);
+  filename = get_path (filename, file_path);
+  if (filename == NULL)
+  {
+    pthread_mutex_unlock (&lock);
+    return (-1);
+  }
+
+  status = buffer_add_string (filename, &buffer_ptr, &buffer_free);
+  if (status != 0)
+  {
+    pthread_mutex_unlock (&lock);
+    rrd_set_error ("rrdc_first: out of memory");
+    return (-1);
+  }
+  status = buffer_add_ulong (rraindex, &buffer_ptr, &buffer_free);
+  if (status != 0)
+  {
+    pthread_mutex_unlock (&lock);
+    rrd_set_error ("rrdc_first: out of memory");
+    return (-1);
+  }
+
+  assert (buffer_free < sizeof (buffer));
+  buffer_size = sizeof (buffer) - buffer_free;
+  assert (buffer[buffer_size - 1] == ' ');
+  buffer[buffer_size - 1] = '\n';
+
+  res = NULL;
+  status = request (buffer, buffer_size, &res);
+  pthread_mutex_unlock (&lock);
+
+  if (status != 0) {
+    rrd_set_error ("rrdcached: %s", res->message);
+    return (-1);
+  }
+  firstup = atol(res->message);
+  response_free (res);
+
+  return (firstup);
+} /* }}} int rrdc_first */
+
+int rrdc_create (const char *filename, /* {{{ */
+    unsigned long pdp_step,
+    time_t last_up,
+    int no_overwrite,
+    int argc,
+    const char **argv)
+{
+  char buffer[4096];
+  char *buffer_ptr;
+  size_t buffer_free;
+  size_t buffer_size;
+  rrdc_response_t *res;
+  int status;
+  char file_path[PATH_MAX];
+  int i;
+
+  if (filename == NULL) {
+    rrd_set_error ("rrdc_create: no filename specified");
+    return (-1);
+  }
+
+  memset (buffer, 0, sizeof (buffer));
+  buffer_ptr = &buffer[0];
+  buffer_free = sizeof (buffer);
+
+  status = buffer_add_string ("create", &buffer_ptr, &buffer_free);
+  if (status != 0) {
+    rrd_set_error ("rrdc_create: out of memory");
+    return (-1);
+  }
+
+  pthread_mutex_lock (&lock);
+  filename = get_path (filename, file_path);
+  if (filename == NULL)
+  {
+    pthread_mutex_unlock (&lock);
+    return (-1);
+  }
+
+  status = buffer_add_string (filename, &buffer_ptr, &buffer_free);
+  status = buffer_add_string ("-b", &buffer_ptr, &buffer_free);
+  status = buffer_add_ulong (last_up, &buffer_ptr, &buffer_free);
+  status = buffer_add_string ("-s", &buffer_ptr, &buffer_free);
+  status = buffer_add_ulong (pdp_step, &buffer_ptr, &buffer_free);
+  if(no_overwrite) {
+    status = buffer_add_string ("-O", &buffer_ptr, &buffer_free);
+  }
+  if (status != 0)
+  {
+    pthread_mutex_unlock (&lock);
+    rrd_set_error ("rrdc_create: out of memory");
+    return (-1);
+  }
+
+  for( i=0; i<argc; i++ ) {
+    if( argv[i] ) {
+      status = buffer_add_string (argv[i], &buffer_ptr, &buffer_free);
+      if (status != 0)
+      {
+        pthread_mutex_unlock (&lock);
+        rrd_set_error ("rrdc_create: out of memory");
+        return (-1);
+      }
+	}
+  }
+
+  /* buffer ready to send? */
+  assert (buffer_free < sizeof (buffer));
+  buffer_size = sizeof (buffer) - buffer_free;
+  assert (buffer[buffer_size - 1] == ' ');
+  buffer[buffer_size - 1] = '\n';
+
+  res = NULL;
+  status = request (buffer, buffer_size, &res);
+  pthread_mutex_unlock (&lock);
+
+  if (status != 0) {
+    rrd_set_error ("rrdcached: %s", res->message);
+    return (-1);
+  }
+  response_free (res);
+  return(0);
+} /* }}} int rrdc_create */
+
+int rrdc_fetch (const char *filename, /* {{{ */
+    const char *cf,
+    time_t *ret_start, time_t *ret_end,
+    unsigned long *ret_step,
+    unsigned long *ret_ds_num,
+    char ***ret_ds_names,
+    rrd_value_t **ret_data)
+{
+  char buffer[4096];
+  char *buffer_ptr;
+  size_t buffer_free;
+  size_t buffer_size;
+  rrdc_response_t *res;
+  char path_buffer[PATH_MAX];
+  const char *path_ptr;
+
+  char *str_tmp;
+  unsigned long flush_version;
+
+  time_t start;
+  time_t end;
+  unsigned long step;
+  unsigned long ds_num;
+  char **ds_names;
+
+  rrd_value_t *data;
+  size_t data_size;
+  size_t data_fill;
+
+  int status;
+  size_t current_line;
+  time_t t;
+
+  if ((filename == NULL) || (cf == NULL))
+    return (-1);
+
+  /* Send request {{{ */
+  memset (buffer, 0, sizeof (buffer));
+  buffer_ptr = &buffer[0];
+  buffer_free = sizeof (buffer);
+
+  status = buffer_add_string ("FETCH", &buffer_ptr, &buffer_free);
+  if (status != 0)
+    return (ENOBUFS);
+
+  /* change to path for rrdcached */
+  path_ptr = get_path (filename, path_buffer);
+  if (path_ptr == NULL)
+    return (EINVAL);
+
+  status = buffer_add_string (path_ptr, &buffer_ptr, &buffer_free);
+  if (status != 0)
+    return (ENOBUFS);
+
+  status = buffer_add_string (cf, &buffer_ptr, &buffer_free);
+  if (status != 0)
+    return (ENOBUFS);
+
+  if ((ret_start != NULL) && (*ret_start > 0))
+  {
+    char tmp[64];
+    snprintf (tmp, sizeof (tmp), "%lu", (unsigned long) *ret_start);
+    tmp[sizeof (tmp) - 1] = 0;
+    status = buffer_add_string (tmp, &buffer_ptr, &buffer_free);
+    if (status != 0)
+      return (ENOBUFS);
+
+    if ((ret_end != NULL) && (*ret_end > 0))
+    {
+      snprintf (tmp, sizeof (tmp), "%lu", (unsigned long) *ret_end);
+      tmp[sizeof (tmp) - 1] = 0;
+      status = buffer_add_string (tmp, &buffer_ptr, &buffer_free);
+      if (status != 0)
+        return (ENOBUFS);
+    }
+  }
+
+  assert (buffer_free < sizeof (buffer));
+  buffer_size = sizeof (buffer) - buffer_free;
+  assert (buffer[buffer_size - 1] == ' ');
+  buffer[buffer_size - 1] = '\n';
+
+  res = NULL;
+  status = request (buffer, buffer_size, &res);
+  if (status != 0)
+    return (status);
+
+  status = res->status;
+  if (status < 0)
+  {
+    rrd_set_error ("rrdcached: %s", res->message);
+    response_free (res);
+    return (status);
+  }
+  /* }}} Send request */
+
+  ds_names = NULL;
+  ds_num = 0;
+  data = NULL;
+  current_line = 0;
+
+  /* Macros to make error handling a little easier (i. e. less to type and
+   * read. `BAIL_OUT' sets the error message, frees all dynamically allocated
+   * variables and returns the provided status code. */
+#define BAIL_OUT(status, ...) do { \
+    rrd_set_error ("rrdc_fetch: " __VA_ARGS__); \
+    free (data); \
+    if (ds_names != 0) { size_t k; for (k = 0; k < ds_num; k++) free (ds_names[k]); } \
+    free (ds_names); \
+    response_free (res); \
+    return (status); \
+  } while (0)
+
+#define READ_NUMERIC_FIELD(name,type,var) do { \
+    char *key; \
+    unsigned long value; \
+    assert (current_line < res->lines_num); \
+    status = parse_ulong_header (res->lines[current_line], &key, &value); \
+    if (status != 0) \
+      BAIL_OUT (-1, "Unable to parse header `%s'", name); \
+    if (strcasecmp (key, name) != 0) \
+      BAIL_OUT (-1, "Unexpected header line: Expected `%s', got `%s'", name, key); \
+    var = (type) value; \
+    current_line++; \
+  } while (0)
+
+  if (res->lines_num < 1)
+    BAIL_OUT (-1, "Premature end of response packet");
+
+  /* We're making some very strong assumptions about the fields below. We
+   * therefore check the version of the `flush' command first, so that later
+   * versions can change the order of fields and it's easier to implement
+   * backwards compatibility. */
+  READ_NUMERIC_FIELD ("FlushVersion", unsigned long, flush_version);
+  if (flush_version != 1)
+    BAIL_OUT (-1, "Don't know how to handle flush format version %lu.",
+        flush_version);
+
+  if (res->lines_num < 5)
+    BAIL_OUT (-1, "Premature end of response packet");
+
+  READ_NUMERIC_FIELD ("Start", time_t, start);
+  READ_NUMERIC_FIELD ("End", time_t, end);
+  if (start >= end)
+    BAIL_OUT (-1, "Malformed start and end times: start = %lu; end = %lu;",
+        (unsigned long) start,
+        (unsigned long) end);
+
+  READ_NUMERIC_FIELD ("Step", unsigned long, step);
+  if (step < 1)
+    BAIL_OUT (-1, "Invalid number for Step: %lu", step);
+
+  READ_NUMERIC_FIELD ("DSCount", unsigned long, ds_num);
+  if (ds_num < 1)
+    BAIL_OUT (-1, "Invalid number for DSCount: %lu", ds_num);
+  
+  /* It's time to allocate some memory */
+  ds_names = calloc ((size_t) ds_num, sizeof (*ds_names));
+  if (ds_names == NULL)
+    BAIL_OUT (-1, "Out of memory");
+
+  status = parse_char_array_header (res->lines[current_line],
+      &str_tmp, ds_names, (size_t) ds_num, /* alloc = */ 1);
+  if (status != 0)
+    BAIL_OUT (-1, "Unable to parse header `DSName'");
+  if (strcasecmp ("DSName", str_tmp) != 0)
+    BAIL_OUT (-1, "Unexpected header line: Expected `DSName', got `%s'", str_tmp);
+  current_line++;
+
+  data_size = ds_num * (end - start) / step;
+  if (data_size < 1)
+    BAIL_OUT (-1, "No data returned or headers invalid.");
+
+  if (res->lines_num != (6 + (data_size / ds_num)))
+    BAIL_OUT (-1, "Got %zu lines, expected %zu",
+        res->lines_num, (6 + (data_size / ds_num)));
+
+  data = calloc (data_size, sizeof (*data));
+  if (data == NULL)
+    BAIL_OUT (-1, "Out of memory");
+  
+
+  data_fill = 0;
+  for (t = start + step; t <= end; t += step, current_line++)
+  {
+    time_t tmp;
+
+    assert (current_line < res->lines_num);
+
+    status = parse_value_array_header (res->lines[current_line],
+        &tmp, data + data_fill, (size_t) ds_num);
+    if (status != 0)
+      BAIL_OUT (-1, "Cannot parse value line");
+
+    data_fill += (size_t) ds_num;
+  }
+
+  *ret_start = start;
+  *ret_end = end;
+  *ret_step = step;
+  *ret_ds_num = ds_num;
+  *ret_ds_names = ds_names;
+  *ret_data = data;
+
+  response_free (res);
+  return (0);
+#undef READ_NUMERIC_FIELD
+#undef BAIL_OUT
+} /* }}} int rrdc_flush */
 
 /* convenience function; if there is a daemon specified, or if we can
  * detect one from the environment, then flush the file.  Otherwise, no-op