--- /dev/null
+! Copyright (C) 2009 Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
+USING: accessors alien alien.syntax assocs help.markup
+help.syntax io.backend kernel namespaces ;
+IN: alien.libraries
+
+HELP: <library>
+{ $values
+ { "path" "a pathname string" } { "abi" "the ABI used by the library, either " { $snippet "cdecl" } " or " { $snippet "stdcall" } }
+ { "library" library } }
+{ $description "Opens a C library using the path and ABI parameters and outputs a library tuple." }
+{ $notes "User code should use " { $link add-library } " so that the opened library is added to a global hashtable, " { $link libraries } "." } ;
+
+HELP: libraries
+{ $description "A global hashtable that keeps a list of open libraries. Use the " { $link add-library } " word to construct a library and add it with a single call." } ;
+
+HELP: library
+{ $values { "name" "a string" } { "library" "a hashtable" } }
+{ $description "Looks up a library by its logical name. The library object is a hashtable with the following keys:"
+ { $list
+ { { $snippet "name" } " - the full path of the C library binary" }
+ { { $snippet "abi" } " - the ABI used by the library, either " { $snippet "cdecl" } " or " { $snippet "stdcall" } }
+ { { $snippet "dll" } " - an instance of the " { $link dll } " class; only set if the library is loaded" }
+ }
+} ;
+
+HELP: dlopen ( path -- dll )
+{ $values { "path" "a pathname string" } { "dll" "a DLL handle" } }
+{ $description "Opens a native library and outputs a handle which may be passed to " { $link dlsym } " or " { $link dlclose } "." }
+{ $errors "Throws an error if the library could not be found, or if loading fails for some other reason." }
+{ $notes "This is the low-level facility used to implement " { $link load-library } ". Use the latter instead." } ;
+
+HELP: dlsym ( name dll -- alien )
+{ $values { "name" "a C symbol name" } { "dll" "a DLL handle" } { "alien" "an alien pointer" } }
+{ $description "Looks up a symbol in a native library. If " { $snippet "dll" } " is " { $link f } " looks for the symbol in the runtime executable." }
+{ $errors "Throws an error if the symbol could not be found." } ;
+
+HELP: dlclose ( dll -- )
+{ $values { "dll" "a DLL handle" } }
+{ $description "Closes a DLL handle created by " { $link dlopen } ". This word might not be implemented on all platforms." } ;
+
+HELP: load-library
+{ $values { "name" "a string" } { "dll" "a DLL handle" } }
+{ $description "Loads a library by logical name and outputs a handle which may be passed to " { $link dlsym } " or " { $link dlclose } ". If the library is already loaded, returns the existing handle." } ;
+
+HELP: add-library
+{ $values { "name" "a string" } { "path" "a string" } { "abi" "one of " { $snippet "\"cdecl\"" } " or " { $snippet "\"stdcall\"" } } }
+{ $description "Defines a new logical library named " { $snippet "name" } " located in the file system at " { $snippet "path" } "and the specified ABI." }
+{ $notes "Because the entire source file is parsed before top-level forms are executed, " { $link add-library } " cannot be used in the same file as " { $link POSTPONE: FUNCTION: } " definitions from that library. The " { $link add-library } " call will happen too late, after compilation, and the alien calls will not work."
+$nl
+"Instead, " { $link add-library } " calls must either be placed in different source files from those that use that library, or alternatively, " { $link "syntax-immediate" } " can be used to load the library before compilation." }
+{ $examples "Here is a typical usage of " { $link add-library } ":"
+{ $code
+ "<< \"freetype\" {"
+ " { [ os macosx? ] [ \"libfreetype.6.dylib\" \"cdecl\" add-library ] }"
+ " { [ os windows? ] [ \"freetype6.dll\" \"cdecl\" add-library ] }"
+ " [ drop ]"
+ "} cond >>"
+}
+"Note the parse time evaluation with " { $link POSTPONE: << } "." } ;
--- /dev/null
+! Copyright (C) 2009 Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
+USING: accessors alien assocs io.backend kernel namespaces ;
+IN: alien.libraries
+
+SYMBOL: libraries
+
+libraries [ H{ } clone ] initialize
+
+TUPLE: library path abi dll ;
+
+: library ( name -- library ) libraries get at ;
+
+: <library> ( path abi -- library )
+ over dup [ dlopen ] when \ library boa ;
+
+: load-library ( name -- dll )
+ library dup [ dll>> ] when ;
+
+: add-library ( name path abi -- )
+ [ dup [ normalize-path ] when ] dip
+ <library> swap libraries get set-at ;