redis.c

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/*
 *   This program is 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; either version 2 of the License, or (at
 *   your option) any later version.
 *
 *   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
 */
 
/**
 * $Id: 7c5beedf6a2f27aed1e03ee3e33a06f21fd63920 $
 * @file redis.c
 * @brief Common functions for interacting with Redis via hiredis
 *
 * @copyright 2015 Arran Cudbard-Bell (a.cudbardb@freeradius.org)
 * @copyright 2000,2006,2015 The FreeRADIUS server project
 * @copyright 2011 TekSavvy Solutions (gabe@teksavvy.com)
 */
#include <freeradius-devel/redis/base.h>
#include <freeradius-devel/util/debug.h>
#include <freeradius-devel/util/value.h>
 
fr_table_num_sorted_t const redis_reply_types[] = {
        { L("array"),           REDIS_REPLY_ARRAY       },
        { L("error"),           REDIS_REPLY_ERROR       },
        { L("integer"),         REDIS_REPLY_INTEGER     },
        { L("nil"),             REDIS_REPLY_NIL         },
        { L("status"),          REDIS_REPLY_STATUS      },
        { L("string"),          REDIS_REPLY_STRING      }
};
size_t redis_reply_types_len = NUM_ELEMENTS(redis_reply_types);
 
fr_table_num_sorted_t const redis_rcodes[] = {
        { L("ask"),             REDIS_RCODE_ASK         },
        { L("error"),           REDIS_RCODE_ERROR       },
        { L("move"),            REDIS_RCODE_MOVE        },
        { L("reconnect"),       REDIS_RCODE_RECONNECT   },
        { L("success"),         REDIS_RCODE_SUCCESS     },
        { L("try again"),       REDIS_RCODE_TRY_AGAIN   }
};
size_t redis_rcodes_len = NUM_ELEMENTS(redis_rcodes);
 
/** Print the version of libhiredis the server was built against
 *
 */
void fr_redis_version_print(void)
{
        INFO("libfreeradius-redis: libhiredis version: %i.%i.%i", HIREDIS_MAJOR, HIREDIS_MINOR, HIREDIS_PATCH);
}
 
/** Check the reply for errors
 *
 * @param[in] conn used to issue the command.
 * @param[in] reply to process.
 * @return
 *      - REDIS_RCODE_TRY_AGAIN - If the operation should be retries.
 *      - REDIS_RCODE_MOVED     - If the key has been permanently moved.
 *      - REDIS_RCODE_ASK       - If the key has been temporarily moved.
 *      - REDIS_RCODE_SUCCESS   - if no errors.
 *      - REDIS_RCODE_ERROR     - on command/server error.
 *      - REDIS_RCODE_NO_SCRIPT - script specified by evalsha doesn't exist.
 *      - REDIS_RCODE_RECONNECT - on connection error (probably needs reconnecting).
 */
fr_redis_rcode_t fr_redis_command_status(fr_redis_conn_t *conn, redisReply *reply)
{
        size_t i = 0;
 
        if (!reply) switch (conn->handle->err) {
        case REDIS_OK:
                break;
 
        case REDIS_ERR_IO:
        case REDIS_ERR_EOF:
        case REDIS_ERR_OTHER:
                fr_strerror_printf("Connection error: %s", conn->handle->errstr);
                return REDIS_RCODE_RECONNECT;
 
        default:
        case REDIS_ERR_PROTOCOL:
                fr_strerror_printf("Command error: %s", conn->handle->errstr);
                return REDIS_RCODE_ERROR;
        }
 
        if (reply) switch (reply->type) {
        case REDIS_REPLY_STATUS:
                return REDIS_RCODE_SUCCESS;
 
        case REDIS_REPLY_ERROR:
                /*
                 *      May indicate the connection handle is bad.
                 */
                fr_assert_msg(reply->str, "Error response contained no error string");
 
                fr_strerror_printf("Server error: %s", reply->str);
                if (strncmp(REDIS_ERROR_MOVED_STR, reply->str, sizeof(REDIS_ERROR_MOVED_STR) - 1) == 0) {
                        return REDIS_RCODE_MOVE;
                }
                if (strncmp(REDIS_ERROR_ASK_STR, reply->str, sizeof(REDIS_ERROR_ASK_STR) - 1) == 0) {
                        return REDIS_RCODE_ASK;
                }
                if (strncmp(REDIS_ERROR_TRY_AGAIN_STR, reply->str, sizeof(REDIS_ERROR_TRY_AGAIN_STR) - 1) == 0) {
                        return REDIS_RCODE_TRY_AGAIN;
                }
                if (strncmp(REDIS_ERROR_NO_SCRIPT_STR, reply->str, sizeof(REDIS_ERROR_NO_SCRIPT_STR) - 1) == 0) {
                        return REDIS_RCODE_NO_SCRIPT;
                }
                return REDIS_RCODE_ERROR;
 
        /*
         *      Recurse to check for nested errors
         */
        case REDIS_REPLY_ARRAY:
                for (i = 0; i < reply->elements; i++) {
                        int ret;
 
                        ret = fr_redis_command_status(conn, reply->element[i]);
                        if (ret < 0) return ret;
                }
                break;
 
        default:
                break;
        }
        return REDIS_RCODE_SUCCESS;
}
 
/** Print the response data in a useful treelike form
 *
 * @param[in] lvl to print data at.
 * @param[in] reply to print.
 * @param[in] request The current request.
 * @param[in] idx Response number.
 * @param[in] status code from processing last reply.
 */
void fr_redis_reply_print(fr_log_lvl_t lvl, redisReply *reply, request_t *request, int idx, fr_redis_rcode_t status)
{
        size_t i = 0;
 
        if (!reply) return;
 
        switch (reply->type) {
        case REDIS_REPLY_ERROR:
                if (status == REDIS_RCODE_MOVE) {
                        ROPTIONAL(RWARN, WARN, "(%i) warn    : %s", idx, reply->str);
                } else {
                        ROPTIONAL(REDEBUG, ERROR, "(%i) error   : %s", idx, reply->str);
                }
                break;
 
        case REDIS_REPLY_STATUS:
                ROPTIONAL(RDEBUGX, DEBUGX, lvl, "(%i) status  : %s", idx, reply->str);
                break;
 
        case REDIS_REPLY_STRING:
                ROPTIONAL(RDEBUGX, DEBUGX, lvl, "(%i) string  : %s", idx, reply->str);
                break;
 
        case REDIS_REPLY_INTEGER:
                ROPTIONAL(RDEBUGX, DEBUGX, lvl, "(%i) integer : %lld", idx, reply->integer);
                break;
 
        case REDIS_REPLY_NIL:
                ROPTIONAL(RDEBUGX, DEBUGX, lvl, "(%i) nil", idx);
                break;
 
        case REDIS_REPLY_ARRAY:
                ROPTIONAL(RDEBUGX, DEBUGX, lvl, "(%i) array[%zu]", idx, reply->elements);
                for (i = 0; i < reply->elements; i++) {
                        if (request) RINDENT();
                        fr_redis_reply_print(lvl, reply->element[i], request, i, status);
                        if (request) REXDENT();
                }
                break;
        }
}
 
/** Convert a string or integer type to #fr_value_box_t of specified type
 *
 * Will work with REDIS_REPLY_STRING (which is converted to #FR_TYPE_STRING
 * then cast to dst_type), or REDIS_REPLY_INTEGER (which is converted to
 * #FR_TYPE_UINT64, then cast to dst_type).
 *
 * @note Any unsupported types will trigger an assert. You must check the
 *      reply type prior to calling this function.
 *
 * @param[in,out] ctx           to allocate any buffers in.
 * @param[out] out              Where to write the cast type.
 * @param[in] reply             to process.
 * @param[in] dst_type          to convert to. May be FR_TYPE_VOID
 *                              to infer type.
 * @param[in] dst_enumv         Used to convert string types to
 *                              integers for attribute with enumerated
 *                              values.
 * @param[in] box_error         If true then REDIS_REPLY_ERROR will be
 *                              copied to a box, otherwise we'll return
 *                              and error with the contents of the error
 *                              available on the thread local error stack.
 * @param[in] shallow           If true, we shallow copy strings.
 * @return
 *      - 1 if we received a NIL reply.
 *      - 0 on success.
 *      - -1 on cast or parse failure.
 */
int fr_redis_reply_to_value_box(TALLOC_CTX *ctx, fr_value_box_t *out, redisReply *reply,
                                fr_type_t dst_type, fr_dict_attr_t const *dst_enumv,
                                bool box_error, bool shallow)
{
        fr_value_box_t  in;
        fr_value_box_t  *to_cast;
 
        if (dst_type != FR_TYPE_VOID) {
                fr_value_box_init_null(&in);
                to_cast = &in;
        } else {
                to_cast = out;
        }
 
        switch (reply->type) {
        case REDIS_REPLY_NIL:
                fr_value_box_init(out, FR_TYPE_NULL, NULL, false);
                return 1;
 
        /*
         *      Try and convert the integer to the smallest
         *      and simplest type possible, to give the cast
         *      the greatest chance of success.
         */
        case REDIS_REPLY_INTEGER:
                if (reply->integer < INT32_MIN) {       /* 64bit signed */
                        fr_value_box(to_cast, (int64_t) reply->integer, true);
                }
                else if (reply->integer < INT16_MIN) {  /* 32bit signed */
                        fr_value_box(to_cast, (int32_t) reply->integer, true);
                }
                else if (reply->integer < INT8_MIN) {   /* 16bit signed */
                        fr_value_box(to_cast, (int16_t) reply->integer, true);
                }
                else if (reply->integer < 0) {  /* 8bit signed */
                        fr_value_box(to_cast, (int8_t) reply->integer, true);
                }
                else if (reply->integer > UINT32_MAX) { /* 64bit unsigned */
                        fr_value_box(to_cast, (uint64_t) reply->integer, true);
                }
                else if (reply->integer > UINT16_MAX) { /* 32bit unsigned */
                        fr_value_box(to_cast, (uint32_t) reply->integer, true);
                }
                else if (reply->integer > UINT8_MAX) {  /* 16bit unsigned */
                        fr_value_box(to_cast, (uint16_t) reply->integer, true);
                }
                else {                                  /* 8bit unsigned */
                        fr_value_box(to_cast, (uint8_t) reply->integer, true);
                }
                break;
 
#if HIREDIS_MAJOR >= 1
        case REDIS_REPLY_DOUBLE:
                /* reply->str is \0 terminated in this case */
                fr_value_box(to_cast, strtod(reply->str, NULL), true);
                break;
 
        case REDIS_REPLY_BOOL:
                fr_value_box(to_cast, (bool)reply->integer, true);
                break;
#endif
 
        case REDIS_REPLY_ERROR:
                if (!box_error) {
                        fr_strerror_printf("Redis error: %pV",
                                           fr_box_strvalue_len(reply->str, reply->len));
                        return -1;
                }
                FALL_THROUGH;
 
#if HIREDIS_MAJOR >= 1
        case REDIS_REPLY_BIGNUM:        /* FIXME - Could try and convert to integer ? */
#endif
        case REDIS_REPLY_STRING:
        case REDIS_REPLY_STATUS:
                fr_value_box_init(out, FR_TYPE_STRING, NULL, false);
 
                if (shallow) {
                        fr_value_box_bstrndup_shallow(to_cast, NULL, reply->str, reply->len, true);
                } else {
                        if (fr_value_box_bstrndup(to_cast->talloced ? to_cast : ctx, to_cast, NULL,
                                                  reply->str, reply->len, true) < 0) return -1;
                }
                break;
 
#if HIREDIS_MAJOR >= 1
        case REDIS_REPLY_VERB:
        {
                fr_value_box_t *verb, *vtype;
 
                fr_value_box_init(out, FR_TYPE_GROUP, NULL, true);
 
                verb = fr_value_box_alloc(ctx, FR_TYPE_STRING, NULL);
                if (unlikely(!verb)) {
                        fr_strerror_const("Out of memory");
                        return -1;
                }
                if (fr_value_box_bstrndup(verb, verb, NULL, reply->str, reply->len, true) < 0) return -1;
                fr_value_box_list_insert_head(&out->vb_group, verb);
 
                vtype = fr_value_box_alloc(ctx, FR_TYPE_STRING, NULL);
                if (unlikely(!vtype)) {
                        fr_strerror_const("Out of memory");
                        talloc_free(verb);
                        return -1;
                }
                if (fr_value_box_strdup(ctx, vtype, NULL, reply->vtype, true) < 0) return -1;
                fr_value_box_list_insert_head(&out->vb_group, vtype);
 
        }
                break;
#endif
 
#if HIREDIS_MAJOR >= 1
        case REDIS_REPLY_SET:
        case REDIS_REPLY_MAP:
        case REDIS_REPLY_PUSH:
#endif
        case REDIS_REPLY_ARRAY:
        {
                fr_value_box_t *vb;
                size_t i;
 
                fr_value_box_init(out, FR_TYPE_GROUP, NULL, true);
 
                for (i = 0; i < reply->elements; i++) {
                        vb = fr_value_box_alloc_null(ctx);
                        if (unlikely(!vb)) {
                        array_error:
                                fr_value_box_list_talloc_free(&out->vb_group);
                                return -1;
                        }
 
                        if (fr_redis_reply_to_value_box(vb, vb, reply->element[i],
                                                        FR_TYPE_VOID, NULL, box_error, shallow) < 0) goto array_error;
                        fr_value_box_list_insert_tail(&out->vb_group, vb);
                }
        }
        }
 
        if ((dst_type != FR_TYPE_VOID) && (fr_value_box_cast(ctx, out, dst_type, dst_enumv, to_cast) < 0)) return -1;
 
        return 0;
}
 
/** Convert a pair of redis reply objects to a map
 *
 * The maps can then be applied using #map_to_request.
 *
 * @param[in,out] ctx to allocate maps in.
 * @param[out] out Where to write the head of the new maps list.
 * @param[in] request The current request.
 * @param[in] key to process.
 * @param[in] op to process.
 * @param[in] value to process.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
int fr_redis_reply_to_map(TALLOC_CTX *ctx, map_list_t *out, request_t *request,
                          redisReply *key, redisReply *op, redisReply *value)
{
        map_t   *map = NULL;
        ssize_t         slen;
 
        if (key->type != REDIS_REPLY_STRING) {
                REDEBUG("Bad key type, expected string, got %s",
                        fr_table_str_by_value(redis_reply_types, key->type, "<UNKNOWN>"));
        error:
                TALLOC_FREE(map);
                return -1;
        }
 
        if (op->type != REDIS_REPLY_STRING) {
                REDEBUG("Bad key type, expected string, got %s",
                        fr_table_str_by_value(redis_reply_types, op->type, "<UNKNOWN>"));
                goto error;
        }
 
        RDEBUG3("Got key   : %s", key->str);
        RDEBUG3("Got op    : %s", op->str);
        RDEBUG3("Got value : %pV", fr_box_strvalue_len(value->str, value->len));
 
        MEM(map = talloc_zero(ctx, map_t));
        slen = tmpl_afrom_attr_str(map, NULL, &map->lhs, key->str,
                                   &(tmpl_rules_t){
                                        .attr = {
                                                .dict_def = request->dict,
                                                .list_def = request_attr_request
                                        }
                                   });
        if (slen <= 0) {
                REMARKER(key->str, -slen, "%s", fr_strerror());
                goto error;
        }
 
        map->op = fr_table_value_by_str(fr_tokens_table, op->str, T_INVALID);
        if (map->op == T_INVALID) {
                REDEBUG("Invalid operator \"%s\"", op->str);
                goto error;
        }
 
        switch (value->type) {
        case REDIS_REPLY_STRING:
        case REDIS_REPLY_INTEGER:
        {
                fr_value_box_t vb = FR_VALUE_BOX_INITIALISER_NULL(vb);
 
                /* Logs own errors */
                if (fr_redis_reply_to_value_box(map, &vb, value,
                                                tmpl_attr_tail_da(map->lhs)->type, tmpl_attr_tail_da(map->lhs), false, false) < 0) {
                        RPEDEBUG("Failed converting Redis data");
                        goto error;
                }
 
                /* This will only fail only memory allocation errors */
                if (tmpl_afrom_value_box(map, &map->rhs, &vb, true) < 0) goto error;
        }
                break;
 
        default:
                REDEBUG("Bad value type, expected string or integer, got %s",
                        fr_table_str_by_value(redis_reply_types, value->type, "<UNKNOWN>"));
                goto error;
 
        }
        MAP_VERIFY(map);
 
        map_list_insert_tail(out, map);
 
        return 0;
}
 
/** Add a single map pair to an existing command string as three elements
 *
 * - Integer types will be encoded as integers.
 * - Strings and octets will be encoded in their raw form.
 * - Other types will be converted to their printable form and will be encoded as strings.
 *
 * @note lhs must be a #TMPL_TYPE_ATTR.
 * @note rhs must be a #TMPL_TYPE_DATA.
 *
 * @param pool to allocate any buffers in.
 * @param out Where to write pointers to the member of the tuple. Unused elements should be
 *      a multiple of three, and it should have at least three unused elements.
 * @param out_len Where to write the size of the data pointed to by the equivalent index
 *      in the out array.
 * @param map to convert.
 * @return
 *      0 on success.
 *      -1 on failure.
 */
int fr_redis_tuple_from_map(TALLOC_CTX *pool, char const *out[], size_t out_len[], map_t *map)
{
        char            *new;
 
        char            key_buf[256];
        fr_sbuff_t      key_buf_sbuff = FR_SBUFF_OUT(key_buf, sizeof(key_buf));
        char            *key;
        size_t          key_len;
        ssize_t         slen;
 
        fr_assert(tmpl_is_attr(map->lhs));
        fr_assert(tmpl_is_data(map->rhs));
 
        slen = tmpl_print(&key_buf_sbuff, map->lhs, NULL);
        if (slen < 0) {
                fr_strerror_printf("Key too long.  Must be < " STRINGIFY(sizeof(key_buf)) " "
                                   "bytes, got %zu bytes", (size_t)(slen * -1));
                return -1;
        }
        key_len = (size_t)slen;
        key = talloc_bstrndup(pool, fr_sbuff_start(&key_buf_sbuff), key_len);
        if (!key) return -1;
 
        switch (tmpl_value_type(map->rhs)) {
        case FR_TYPE_STRING:
        case FR_TYPE_OCTETS:
                out[2] = tmpl_value(map->rhs)->datum.ptr;
                out_len[2] = tmpl_value_length(map->rhs);
                break;
 
        /*
         *      For everything else we get the string representation
         */
        default:
                fr_value_box_aprint(pool, &new, tmpl_value(map->rhs), NULL);
                if (!new) {
                        talloc_free(key);
                        return -1;
                }
                out[2] = new;
                out_len[2] = talloc_array_length(new) - 1;
                break;
        }
 
        out[0] = key;
        out_len[0] = key_len;
        out[1] = fr_table_str_by_value(fr_tokens_table, map->op, NULL);
        out_len[1] = strlen(out[1]);
 
        return 0;
}
 
/** Simplifies handling of pipelined commands with Redis cluster
 *
 * Retrieve all available pipelined responses, and write them to the array.
 *
 * On encountering an error, all previously retrieved responses are freed, and the reply
 * containing the error is written to the first element of out. All responses after the
 * error are also freed.
 *
 * If the number of responses != pipelined, that's also an error, a very serious one,
 * in libhiredis or Redis.  We can't really do much here apart from error out.
 *
 * @param[out] pipelined        Number of pipelined commands we sent to the server.
 * @param[out] rcode            Status of the first errored response, or REDIS_RCODE_SUCCESS
 *                              if all responses were processed.
 * @param[out] out              Where to write the replies from pipelined commands.
 *                              Will contain exactly 1 element on error WHICH MUST BE FREED,
 *                              else the number passed in pipelined.
 * @param[in] out_len           number of elements in out.
 * @param[in] conn              the pipelined commands were issued on.
 * @return
 *      - #REDIS_RCODE_SUCCESS on success.
 *      - #REDIS_RCODE_ERROR on command/response mismatch or command error.
 *      - REDIS_RCODE_* on other errors;
 */
fr_redis_rcode_t fr_redis_pipeline_result(unsigned int *pipelined, fr_redis_rcode_t *rcode,
                                          redisReply *out[], size_t out_len,
                                          fr_redis_conn_t *conn)
{
        size_t                  i;
        redisReply              **out_p = out;
        fr_redis_rcode_t        status = REDIS_RCODE_SUCCESS;
        redisReply              *reply = NULL;
 
        fr_assert(out_len >= (size_t)*pipelined);
 
        fr_strerror_clear();    /* Clear any outstanding errors */
 
        if ((size_t) *pipelined > out_len) {
                for (i = 0; i < (size_t)*pipelined; i++) {
                        if (redisGetReply(conn->handle, (void **)&reply) != REDIS_OK) break;
                        fr_redis_reply_free(&reply);
                }
 
                *pipelined = 0;                 /* all outstanding responses should be cleared */
 
                fr_strerror_const("Too many pipelined commands");
                out[0] = NULL;
                return REDIS_RCODE_ERROR;
        }
 
        for (i = 0; i < (size_t)*pipelined; i++) {
                bool maybe_more = false;
 
                /*
                 *      we don't need to check the return code here,
                 *      as it's also stored in the conn->handle.
                 */
                reply = NULL;   /* redisGetReply doesn't NULLify reply on error *sigh* */
                if (redisGetReply(conn->handle, (void **)&reply) == REDIS_OK) maybe_more = true;
                status = fr_redis_command_status(conn, reply);
                *out_p++ = reply;
 
                /*
                 *      Bail out of processing responses,
                 *      free the remaining ones (leaving this one intact)
                 *      pass control back to the cluster code.
                 */
                if (maybe_more && (status != REDIS_RCODE_SUCCESS)) {
                        size_t j;
                error:
                        /*
                         *      Append the hiredis error
                         */
                        if (conn->handle->errstr[0]) fr_strerror_printf_push("%s", conn->handle->errstr);
 
                        /*
                         *      Free everything that came before the bad reply
                         */
                        for (j = 0; j < i; j++) {
                                fr_redis_reply_free(&out[j]);
                                out[j] = NULL;
                        }
 
                        /*
                         *      ...and drain the rest of the pipelined responses
                         */
                        for (j = i + 1; j < (size_t)*pipelined; j++) {
                                redisReply *to_clear;
 
                                if (redisGetReply(conn->handle, (void **)&to_clear) != REDIS_OK) break;
                                fr_redis_reply_free(&to_clear);
                        }
 
                        out[0] = reply;
 
                        *rcode = status;
                        *pipelined = 0;          /* all outstanding responses should be cleared */
 
                        return reply ? 1 : 0;
                }
        }
 
        if (i != (size_t)*pipelined) {
                fr_strerror_printf("Expected %u responses, got %zu", *pipelined, i);
                status = REDIS_RCODE_ERROR;
                goto error;
        }
 
        *rcode = status;
 
        *pipelined = 0;                         /* all outstanding responses should be cleared */
 
        return i;
}
 
/** Get the version of Redis running on the remote server
 *
 * This can be useful for some modules, as it allows adaptive behaviour, or early termination.
 *
 * @param[out] out Where to write the version string.
 * @param[in] out_len Length of the version string buffer.
 * @param[in] conn Used to query the version string.
 * @return
 *      - #REDIS_RCODE_SUCCESS on success.
 *      - #REDIS_RCODE_ERROR on command/response mismatch or command error.
 *      - REDIS_RCODE_* on other errors;
 */
fr_redis_rcode_t fr_redis_get_version(char *out, size_t out_len, fr_redis_conn_t *conn)
{
        redisReply              *reply;
        fr_redis_rcode_t        status;
        char                    *p, *q;
 
        fr_assert(out_len > 0);
        out[0] = '\0';
 
        reply = redisCommand(conn->handle, "INFO SERVER");
        status = fr_redis_command_status(conn, reply);
        if (status != REDIS_RCODE_SUCCESS) return status;
 
        if (reply->type != REDIS_REPLY_STRING) {
                fr_strerror_printf("Bad value type, expected string or integer, got %s",
                                   fr_table_str_by_value(redis_reply_types, reply->type, "<UNKNOWN>"));
        error:
                fr_redis_reply_free(&reply);
                return REDIS_RCODE_ERROR;
        }
 
        p = strstr(reply->str, "redis_version:");
        if (!p) {
                fr_strerror_const("Response did not contain version string");
                goto error;
        }
 
        p = strchr(p, ':');
        fr_assert(p);
        p++;
 
        q = strstr(p, "\r\n");
        if (!q) q = p + strlen(p);
 
        if ((size_t)(q - p) >= out_len) {
                fr_strerror_printf("Version string %zu bytes, expected < %zu bytes", q - p, out_len);
                goto error;
        }
        strlcpy(out, p, (q - p) + 1);
 
        fr_redis_reply_free(&reply);
 
        return REDIS_RCODE_SUCCESS;
}
 
/** Convert version string into a 32bit unsigned integer for comparisons
 *
 * @param[in] version string to parse.
 * @return 32bit unsigned integer representing the version string.
 */
uint32_t fr_redis_version_num(char const *version)
{
        unsigned long num;
        uint32_t ret;
        char const *p = version;
        char *q;
 
        num = strtoul(p, &q, 10);
        if (num > UINT8_MAX) {
                fr_strerror_printf("Major version number %lu greater than " STRINGIFY(UINT8_MAX), num);
                return 0;
        }
 
        if ((p == q) || (q[0] != '.')) {
                fr_strerror_printf("Trailing garbage in Redis version \"%s\"", q);
                return 0;
        }
        ret = num << 24;
        p = q + 1;
 
        num = strtoul(p, &q, 10);
        if (num > UINT8_MAX) {
                fr_strerror_printf("Minor version number %lu greater than " STRINGIFY(UINT8_MAX), num);
                return 0;
        }
 
        if ((p == q) || (q[0] != '.')) {
                fr_strerror_printf("Trailing garbage in Redis version \"%s\"", q);
                return 0;
        }
        ret |= num << 16;
        p = q + 1;
 
        num = strtoul(p, &q, 10);
        if (num > UINT16_MAX) {
                fr_strerror_printf("Minor version number %lu greater than " STRINGIFY(UINT16_MAX), num);
                return 0;
        }
 
        if ((p == q) || (q[0] != '\0')) {
                fr_strerror_printf("Trailing garbage in Redis version \"%s\"", q);
                return 0;
        }
 
        return ret | num;
}