tidying

[users/heiko/exim.git] / doc / doc-docbook / spec.xfpt

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index bfe59fcccbcb746dcbcea25149294ba2f0d400f6..8e7cb4d9275e0b55ad3c84ba0158add9a65393ed 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -6777,13 +6777,34 @@ absolute
 directory path; this is searched for an entry
 whose name is the key by calling the &[lstat()]& function.
 The key may not
-contain any forward slash characters. If &[lstat()]& succeeds, the result of
-the lookup is the name of the entry, which may be a file, directory,
-symbolic link, or any other kind of directory entry.
+contain any forward slash characters.
+If &[lstat()]& succeeds then so does the lookup.
 .new
 .cindex "tainted data" "dsearch result"
-It is regarded as untainted.
+The result is regarded as untainted.
+
+Options for the lookup can be given by appending them after the word "dsearch",
+separated by a comma.  Options, if present, are a comma-separated list having
+each element starting with a tag name and an equals.
+
+Two options are supported, for the return value and for filtering match
+candidates.
+The "ret" option requests an alternate result value of
+the entire path for the entry. Example:
+.code
+${lookup {passwd} dsearch,ret=full {/etc}}
+.endd
+The default result is just the requested entry.
+The "filter" option requests that only directory entries of a given type
+are matched. The match value is one of "file", "dir" or "subdir" (the latter
+not matching "." or ".."). Example:
+.code
+${lookup {passwd} dsearch,filter=file {/etc}}
+.endd
+The default matching is for any entry type, including directories
+and symlinks.
 .wen
+
 An example of how this
 lookup can be used to support virtual domains is given in section
 &<<SECTvirtualdomains>>&.
@@ -7995,12 +8016,14 @@ The &%quote_redis%& expansion operator
 escapes whitespace and backslash characters with a backslash.
 
 .section "Specifying the server in the query" "SECTspeserque"
+.new
 For MySQL, PostgreSQL and Redis lookups (but not currently for Oracle and InterBase),
 it is possible to specify a list of servers with an individual query. This is
-done by starting the query with
+done by appending a comma-separated option to the query type:
 .display
-&`servers=`&&'server1:server2:server3:...'&&`;`&
 .endd
+&`,servers=`&&'server1:server2:server3:...'&
+.wen
 Each item in the list may take one of two forms:
 .olist
 If it contains no slashes it is assumed to be just a host name. The appropriate
@@ -8025,15 +8048,26 @@ mysql_servers = slave1/db/name/pw:\
 .endd
 In an updating lookup, you could then write:
 .code
-${lookup mysql{servers=master; UPDATE ...} }
+${lookup mysql,servers=master {UPDATE ...} }
 .endd
 That query would then be sent only to the master server. If, on the other hand,
 the master is not to be used for reading, and so is not present in the global
 option, you can still update it by a query of this form:
 .code
-${lookup pgsql{servers=master/db/name/pw; UPDATE ...} }
+${lookup pgsql,servers=master/db/name/pw {UPDATE ...} }
 .endd
 
+.new
+An older syntax places the servers speciification before the qury,
+semicolon separated:
+.code
+${lookup mysql{servers=master; UPDATE ...} }
+.endd
+The new version avoids potential issues with tainted
+arguments in the query, for explicit expansion.
+&*Note*&: server specifications in list-style lookups are still problematic.
+.wen
+
 
 .section "Special MySQL features" "SECID73"
 For MySQL, an empty host name or the use of &"localhost"& in &%mysql_servers%&
@@ -8088,8 +8122,8 @@ daemon as in the other SQL databases.
 .oindex &%sqlite_dbfile%&
 The preferred way of specifying the file is by using the 
 &%sqlite_dbfile%& option, set to
-.wen
 an absolute path.
+.wen
 A deprecated method is available, prefixing the query with the filename
 separated by white space.
 This means that the path name cannot contain white space.
@@ -8098,6 +8132,7 @@ It also means that the query cannot use any tainted values, as that taints
 the entire query including the filename - resulting in a refusal to open
 the file.
 
+.new
 Here is a lookup expansion example:
 .code
 sqlite_dbfile = /some/thing/sqlitedb
@@ -8109,6 +8144,7 @@ In a list, the syntax is similar. For example:
 domainlist relay_to_domains = sqlite;\
    select * from relays where ip='$sender_host_address';
 .endd
+.wen
 The only character affected by the &%quote_sqlite%& operator is a single
 quote, which it doubles.
 
@@ -8596,6 +8632,14 @@ whether or not the query succeeds. However, when a lookup is used for the
 &%domains%& option on a router, the data is preserved in the &$domain_data$&
 variable and can be referred to in other options.
 .next
+.new
+If the pattern starts with the name of a lookup type
+of either kind (single-key or query-style) it may be
+followed by a command and options,
+The options are lookup-type specific and consist of a comma-separated list.
+Each item starts with a tag and and equals "=".
+.wen
+.next
 .cindex "domain list" "matching literal domain name"
 If none of the above cases apply, a caseless textual comparison is made
 between the pattern and the domain.