Added an insertbefore option.

library/lineinfile

@@ -61,11 +61,20 @@ options:
     default: EOF
     description:
       - Used with C(state=present). If specified, the line will be inserted
-        after the specified regular expression. Two special values are
-        available; C(BOF) for inserting the line at the beginning of the
-        file, and C(EOF) for inserting the line at the end of the file.
-    choices: [ 'BOF', 'EOF', '*regex*' ]
+        after the specified regular expression. A special value is
+        available; C(EOF) for inserting the line at the end of the file.
+    choices: [ EOF, *regex* ]
     default: EOF
+  insertbefore:
+    required: false
+    default: BOF
+    description:
+      - Used with C(state=present). If specified, the line will be inserted
+        before the specified regular expression. A value is available;
+         C(BOF) for inserting the line at the beginning of the
+        file.
+    choices: [ BOF, *regex* ]
+    default: BOF    
   create:
     required: false
     choices: [ yes, no ]
@@ -85,9 +94,10 @@ examples:
    - code: "lineinfile: \\\"dest=/etc/sudoers state=present regexp='^%wheel' line ='%wheel ALL=(ALL) NOPASSWD: ALL'\\\""
    - code: 'lineinfile: dest=/etc/sudoers state=absent regexp="^%wheel"'
    - code: 'lineinfile: dest=/etc/httpd/conf/httpd.conf regexp="^Listen " insertafter="^#Listen " line="Listen 8080"'
+   - code: 'lineinfile: dest=/etc/services regexp="^# port for http" insertbefore="^www.*80/tcp" line="# port for http by default"'
 """
 
-def present(module, dest, regexp, line, insertafter, create, backup):
+def present(module, dest, regexp, line, insertafter, insertbefore, create, backup):
 
     if os.path.isdir(dest):
         module.fail_json(rc=256, msg='Destination %s is a directory !' % dest)
@@ -107,18 +117,31 @@ def present(module, dest, regexp, line, insertafter, create, backup):
     if not mre.search(line):
         module.fail_json(msg="usage error: line= doesn't match regexp (%s)" % regexp)
 
-    if insertafter in ('BOF', 'EOF'):
-        iare = None
-    else:
-        iare = re.compile(insertafter)
+    if insertbefore and insertafter:
+        module.fail_json(msg="usage error: \"insertbefore\" and \"insertafter\" cannot be combined")
 
+    
+    if insertafter in ('BOF', 'EOF', False):
+        if insertbefore in ('BOF', False):
+            insre = None
+        else:
+            insre = re.compile(insertbefore)
+    else:
+        insre = re.compile(insertafter)
+
+    # index[0] is the line num where regexp has been found
+    # index[1] is the line num where insertafter/inserbefore has been found
     index = [-1, -1]
     for lineno in range(0, len(lines)):
         if mre.search(lines[lineno]):
             index[0] = lineno
-        elif iare is not None and iare.search(lines[lineno]):
-            # + 1 for the next line
-            index[1] = lineno + 1
+        elif insre is not None and insre.search(lines[lineno]):
+            if insertafter:
+                # + 1 for the next line
+                index[1] = lineno + 1
+            if insertbefore:
+                # + 1 for the previous line
+                index[1] = lineno
 
     # Regexp matched a line in the file
     if index[0] != -1:
@@ -130,16 +153,17 @@ def present(module, dest, regexp, line, insertafter, create, backup):
             msg = 'line replaced'
             changed = True
     # Add it to the beginning of the file
-    elif insertafter == 'BOF':
+    # we keep insertafter == 'BOF' for backwards compatibility, but it should be removed eventually
+    elif insertbefore == 'BOF' or insertafter == 'BOF':
         lines.insert(0, line + os.linesep)
         msg = 'line added'
         changed = True
-    # Add it to the end of the file if requested or if insertafter= didn't match
+    # Add it to the end of the file if requested or if insertafter=/insertbefore didn't match
     elif insertafter == 'EOF' or index[1] == -1:
         lines.append(line + os.linesep)
         msg = 'line added'
         changed = True
-    # insertafter= matched
+    # insertafter/insertbefore= matched
     else:
         lines.insert(index[1], line + os.linesep)
         msg = 'line added'
@@ -185,7 +209,8 @@ def main():
             state=dict(default='present', choices=['absent', 'present']),
             regexp=dict(required=True),
             line=dict(aliases=['value']),
-            insertafter=dict(default='EOF'),
+            insertafter=dict(default=False),
+            insertbefore=dict(default=False),
             create=dict(default=False, choices=BOOLEANS),
             backup=dict(default=False, choices=BOOLEANS),
         ),
@@ -199,7 +224,7 @@ def main():
         if 'line' not in params:
             module.fail_json(msg='line= is required with state=present')
         present(module, params['dest'], params['regexp'], params['line'],
-                params['insertafter'], create, backup)
+                params['insertafter'], params['insertbefore'], create, backup)
     else:
         absent(module, params['dest'], params['regexp'], backup)