commit 54ecc11cc4c4cf4a6ed958fd2906f3a791d1c8d2
author Kwon-Young Choi <kwon-young.choi@hotmail.fr> Sat Apr 04 17:27:18 2020 +0200
committer Daniel Stenberg <daniel@haxx.se> Sun Apr 05 11:13:49 2020 +0200
tree d53c220ef41aa1d1a4d7debcf70fbae216ab9744
parent a448a4ce2615373fc63818afede79550f2ca6a14

CURLINFO_CONDITION_UNMET: return true for 304 http status code

In libcurl, CURLINFO_CONDITION_UNMET is used to avoid writing to the
output file if the server did not transfered a file based on time
condition. In the same manner, getting a 304 HTTP response back from the
server, for example after passing a custom If-Match-* header, also
fulfill this condition.

Fixes #5181
Closes #5183

docs/libcurl/curl_easy_getinfo.3

diff --git a/docs/libcurl/curl_easy_getinfo.3 b/docs/libcurl/curl_easy_getinfo.3
index c7b124a..6471653 100644
--- a/docs/libcurl/curl_easy_getinfo.3
+++ b/docs/libcurl/curl_easy_getinfo.3
@@ -210,7 +210,7 @@
 \fICURLINFO_TLS_SESSION(3)\fP. Deprecated option, use
 \fICURLINFO_TLS_SSL_PTR(3)\fP instead!
 .IP CURLINFO_CONDITION_UNMET
-Whether or not a time conditional was met.
+Whether or not a time conditional was met or 304 HTTP response.
 See \fICURLINFO_CONDITION_UNMET(3)\fP
 .IP CURLINFO_RTSP_SESSION_ID
 RTSP session ID.

docs/libcurl/opts/CURLINFO_CONDITION_UNMET.3

diff --git a/docs/libcurl/opts/CURLINFO_CONDITION_UNMET.3 b/docs/libcurl/opts/CURLINFO_CONDITION_UNMET.3
index 2748865..78c28fa 100644
--- a/docs/libcurl/opts/CURLINFO_CONDITION_UNMET.3
+++ b/docs/libcurl/opts/CURLINFO_CONDITION_UNMET.3
@@ -22,7 +22,7 @@
 .\"
 .TH CURLINFO_CONDITION_UNMET 3 "1 Sep 2015" "libcurl 7.44.0" "curl_easy_getinfo options"
 .SH NAME
-CURLINFO_CONDITION_UNMET \- get info on unmet time conditional
+CURLINFO_CONDITION_UNMET \- get info on unmet time conditional or 304 HTTP response.
 .SH SYNOPSIS
 #include <curl/curl.h>
 
@@ -32,7 +32,9 @@
 the previous request didn't match (see \fICURLOPT_TIMECONDITION(3)\fP). Alas,
 if this returns a 1 you know that the reason you didn't get data in return is
 because it didn't fulfill the condition. The long this argument points to will
-get a zero stored if the condition instead was met.
+get a zero stored if the condition instead was met. This can also return 1 if
+the server responded with a 304 HTTP status code, for example after sending a
+custom "If-Match-*" header.
 .SH PROTOCOLS
 HTTP and some
 .SH EXAMPLE

lib/getinfo.c

diff --git a/lib/getinfo.c b/lib/getinfo.c
index 18274e9..84d9fc1 100644
--- a/lib/getinfo.c
+++ b/lib/getinfo.c
@@ -239,8 +239,11 @@
     *param_longp = data->info.conn_local_port;
     break;
   case CURLINFO_CONDITION_UNMET:
-    /* return if the condition prevented the document to get transferred */
-    *param_longp = data->info.timecond ? 1L : 0L;
+    if(data->info.httpcode == 304)
+      *param_longp = 1L;
+    else
+      /* return if the condition prevented the document to get transferred */
+      *param_longp = data->info.timecond ? 1L : 0L;
     break;
   case CURLINFO_RTSP_CLIENT_CSEQ:
     *param_longp = data->state.rtsp_next_client_CSeq;