netrc: don't ignore the login name specified with "--user"

- for "--netrc", don't ignore the login/password specified with "--user",
  only ignore the login/password in the URL.
  This restores the netrc behaviour of curl 7.61.1 and earlier.
- fix the documentation of CURL_NETRC_REQUIRED
- improve the detection of login/password changes when reading .netrc
- don't read .netrc if both login and password are already set

Fixes #3213
Closes #3224

2 files changed, 10 insertions, 9 deletions

diff --git a/docs/cmdline-opts/netrc-file.d b/docs/cmdline-opts/netrc-file.d
index 0b5d2400c..50126d255 100644
--- a/docs/cmdline-opts/netrc-file.d
+++ b/docs/cmdline-opts/netrc-file.d
@@ -5,7 +5,7 @@ Added: 7.21.5
 Mutexed: netrc
 ---
 This option is similar to --netrc, except that you provide the path (absolute
-or relative) to the netrc file that Curl should use.  You can only specify one
+or relative) to the netrc file that curl should use.  You can only specify one
 netrc file per invocation. If several --netrc-file options are provided,
 the last one will be used.
 
diff --git a/docs/libcurl/opts/CURLOPT_NETRC.3 b/docs/libcurl/opts/CURLOPT_NETRC.3
index ee19801ea..21178ef16 100644
--- a/docs/libcurl/opts/CURLOPT_NETRC.3
+++ b/docs/libcurl/opts/CURLOPT_NETRC.3
@@ -47,20 +47,21 @@ standard Unix ftp client does). It should only be readable by user.
 \fIlevel\fP should be set to one of the values described below.
 
 .IP CURL_NETRC_OPTIONAL
-The use of your \fI~/.netrc\fP file is optional, and information in the URL is
-to be preferred.  The file will be scanned for the host and user name (to
-find the password only) or for the host only, to find the first user name and
-password after that \fImachine\fP, which ever information is not specified in
-the URL.
+The use of the \fI~/.netrc\fP file is optional, and information in the URL is
+to be preferred.  The file will be scanned for the host and user name (to find
+the password only) or for the host only, to find the first user name and
+password after that \fImachine\fP, which ever information is not specified.
 
 Undefined values of the option will have this effect.
 .IP CURL_NETRC_IGNORED
-The library will ignore the file and use only the information in the URL.
+The library will ignore the \fI~/.netrc\fP file.
 
 This is the default.
 .IP CURL_NETRC_REQUIRED
-This value tells the library that use of the file is required, to ignore the
-information in the URL, and to search the file for the host only.
+The use of the \fI~/.netrc\fP file is required, and information in the URL is
+to be ignored.  The file will be scanned for the host and user name (to find
+the password only) or for the host only, to find the first user name and
+password after that \fImachine\fP, which ever information is not specified.
 .SH DEFAULT
 CURL_NETRC_IGNORED
 .SH PROTOCOLS