From 7900b48bc73bac45dce50ca43872e1af1412f5d5 Mon Sep 17 00:00:00 2001
From: Binbin <binloveplay1314@qq.com>
Date: Mon, 14 Jun 2021 21:46:45 +0800
Subject: [PATCH] slowlog get command supports passing in -1 to get all logs.
 (#9018)

This was already the case before this commit, but it wasn't clear / intended in the code, now it does.
---
 src/slowlog.c          | 19 ++++++++++++++-----
 tests/unit/slowlog.tcl | 24 +++++++++++++++++++++++-
 2 files changed, 37 insertions(+), 6 deletions(-)

diff --git a/src/slowlog.c b/src/slowlog.c
index b8c13f1cb..320f334a8 100644
--- a/src/slowlog.c
+++ b/src/slowlog.c
@@ -143,8 +143,8 @@ void slowlogCommand(client *c) {
     if (c->argc == 2 && !strcasecmp(c->argv[1]->ptr,"help")) {
         const char *help[] = {
 "GET [<count>]",
-"    Return top <count> entries from the slowlog (default: 10). Entries are",
-"    made of:",
+"    Return top <count> entries from the slowlog (default: 10, -1 mean all).",
+"    Entries are made of:",
 "    id, timestamp, time in microseconds, arguments array, client IP and port,",
 "    client name",
 "LEN",
@@ -168,9 +168,18 @@ NULL
         listNode *ln;
         slowlogEntry *se;
 
-        if (c->argc == 3 &&
-            getLongFromObjectOrReply(c,c->argv[2],&count,NULL) != C_OK)
-            return;
+        if (c->argc == 3) {
+            /* Consume count arg. */
+            if (getRangeLongFromObjectOrReply(c, c->argv[2], -1,
+                    LONG_MAX, &count, "count should be greater than or equal to -1") != C_OK)
+                return;
+
+            if (count == -1) {
+                /* We treat -1 as a special value, which means to get all slow logs.
+                 * Simply set count to the length of server.slowlog.*/
+                count = listLength(server.slowlog);
+            }
+        }
 
         listRewind(server.slowlog,&li);
         totentries = addReplyDeferredLen(c);
diff --git a/tests/unit/slowlog.tcl b/tests/unit/slowlog.tcl
index 52022f90d..b9ac9ddf2 100644
--- a/tests/unit/slowlog.tcl
+++ b/tests/unit/slowlog.tcl
@@ -175,4 +175,26 @@ start_server {tags {"slowlog"} overrides {slowlog-log-slower-than 1000000}} {
         r debug sleep 0.2
         assert_equal [r slowlog len] 0
     } {} {needs:debug}
-}
+
+    test {SLOWLOG - count must be >= -1} {
+       assert_error "ERR count should be greater than or equal to -1" {r slowlog get -2}
+       assert_error "ERR count should be greater than or equal to -1" {r slowlog get -222}
+    }
+
+    test {SLOWLOG - get all slow logs} {
+        r config set slowlog-log-slower-than 0
+        r config set slowlog-max-len 3
+        r slowlog reset
+
+        r set key test
+        r sadd set a b c
+        r incr num
+        r lpush list a
+
+        assert_equal [r slowlog len] 3
+        assert_equal 0 [llength [r slowlog get 0]]
+        assert_equal 1 [llength [r slowlog get 1]]
+        assert_equal 3 [llength [r slowlog get -1]]
+        assert_equal 3 [llength [r slowlog get 3]]
+    }
+}
\ No newline at end of file