The parser and flatc now allow include directories to be specified.

Bug: 17139854
Change-Id: I0eac65d054951e00a8811ad1d80ba8c37012dbf0
Tested: on Linux.

docs/source/Compiler.md

@@ -2,7 +2,7 @@
 
 Usage:
 
-    flatc [ -c ] [ -j ] [ -b ] [ -t ] [ -o PATH ] [ -S ] FILES...
+    flatc [ -c ] [ -j ] [ -b ] [ -t ] [ -o PATH ] [ -I PATH ] [ -S ] FILES...
           [ -- FILES...]
 
 The files are read and parsed in order, and can contain either schemas
@@ -32,6 +32,11 @@ be generated for each file processed:
     current directory. PATH should end in your systems path separator,
     e.g. `/` or `\`.
 
+-   `-I PATH` : when encountering `include` statements, attempt to load the
+    files from this path. Paths will be tried in the order given, and if all
+    fail (or none are specified) it will try to load relative to the path of
+    the schema file being parsed.
+
 -   `-S` : Generate strict JSON (field names are enclosed in quotes).
     By default, no quotes are generated.
 

docs/source/CppUsage.md

@@ -249,6 +249,10 @@ reference definitions in earlier files. Typically this means you first
 load a schema file (which populates `Parser` with definitions), followed
 by one or more JSON files.
 
+As optional argument to `Parse`, you may specify a null-terminated list of
+include paths. If not specified, any include statements try to resolve from
+the current directory.
+
 If there were any parsing errors, `Parse` will return `false`, and
 `Parser::err` contains a human readable error string with a line number
 etc, which you should present to the creator of that file.