htaccess rewrite - prevent multiple redirects - regex

Question

The following regex works perfectly except for under the condition when the user goes to examplesite1.com/site1. When this happens the page fails because of multiple redirects in which it continues to add the request=site1 query to the URL. I thought that adding RewriteCond %{ENV:REDIRECT_STATUS} ^$ would fix this issue however that seemed to not be the case.
This setup is for a multi-domain website. There are three folders site1, site2, and shared. There are also rewrite rules for site2 and shared that are not shown as they do not effect this issue.
# if the resource exists in site1 return it to the user
RewriteCond %{HTTP_HOST} examplesite1.com$
RewriteCond %{DOCUMENT_ROOT}/site1/%{REQUEST_URI} -f
RewriteRule ^(.*)$ /site1/$1 [QSA,L]
# no file found, send URI to CMS
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^(.*)$ /index.php?request=$1 [QSA,L]
complete .htaccess file:
AddDefaultCharset UTF-8
# Disallow browsing file directories
Options -Indexes
RewriteEngine on
RewriteBase /
#remove the trailing slash
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_URI} (.*)/$
RewriteRule ^(.+)/$ /$1 [R=301,L]
RewriteCond %{HTTP_HOST} examplesite1.com$
RewriteCond %{DOCUMENT_ROOT}/site1/%{REQUEST_URI} -f
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteRule ^(.*)$ /site1/$1 [QSA,L]
RewriteCond %{HTTP_HOST} examplesite2.com$
RewriteCond %{DOCUMENT_ROOT}/site2/%{REQUEST_URI} -f
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteRule ^(.*)$ /site2/$1 [QSA,L]
RewriteCond %{DOCUMENT_ROOT}/shared/%{REQUEST_URI} -f
RewriteRule ^(.*)$ /shared/$1 [QSA,L]
# resources not to be public are sent to CMS
RewriteCond %{REQUEST_FILENAME} (\.inc\.|\.tpl$)
RewriteRule ^(.*)$ /index.php?request=$1 [QSA,L]
# no resource found, send URI to CMS
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteRule ^(.*)$ /index.php?request=$1 [QSA,L]

Answer 1

Try adding an extra condition:
RewriteCond %{HTTP_HOST} examplesite1.com$
RewriteCond %{REQUEST_URI} !^/site1/
RewriteCond %{DOCUMENT_ROOT}/site1/%{REQUEST_URI} -f [OR]
RewriteCond %{DOCUMENT_ROOT}/site1/%{REQUEST_URI} -d
RewriteRule ^(.*)$ /site1/$1 [QSA,L]
What looks like may be happening here is that you need to prevent a redirect from happening after one of your other rules get applied. Try adding this right below RewriteBase /:
RewriteCond %{ENV:REDIRECT_STATUS} 200
RewriteRule ^ - [L]