diff options
Diffstat (limited to 'lib/pure/dynlib.nim')
| -rw-r--r-- | lib/pure/dynlib.nim | 112 |
1 files changed, 64 insertions, 48 deletions
diff --git a/lib/pure/dynlib.nim b/lib/pure/dynlib.nim index f31ae94dd..a162fe37f 100644 --- a/lib/pure/dynlib.nim +++ b/lib/pure/dynlib.nim @@ -8,8 +8,8 @@ # ## This module implements the ability to access symbols from shared -## libraries. On POSIX this uses the ``dlsym`` mechanism, on -## Windows ``LoadLibrary``. +## libraries. On POSIX this uses the `dlsym` mechanism, on +## Windows `LoadLibrary`. ## ## Examples ## ======== @@ -17,75 +17,64 @@ ## Loading a simple C function ## --------------------------- ## -## The following example demonstrates loading a function called 'greet' +## The following example demonstrates loading a function called `greet` ## from a library that is determined at runtime based upon a language choice. -## If the library fails to load or the function 'greet' is not found, +## If the library fails to load or the function `greet` is not found, ## it quits with a failure error code. ## -## .. code-block::nim -## -## import dynlib -## -## type -## greetFunction = proc(): cstring {.gcsafe, stdcall.} -## -## let lang = stdin.readLine() -## -## let lib = case lang -## of "french": -## loadLib("french.dll") -## else: -## loadLib("english.dll") -## -## if lib == nil: -## echo "Error loading library" -## quit(QuitFailure) -## -## let greet = cast[greetFunction](lib.symAddr("greet")) -## -## if greet == nil: -## echo "Error loading 'greet' function from library" -## quit(QuitFailure) -## -## let greeting = greet() -## -## echo greeting -## -## unloadLib(lib) -## +runnableExamples: + type + GreetFunction = proc (): cstring {.gcsafe, stdcall.} + + proc loadGreet(lang: string) = + let lib = + case lang + of "french": + loadLib("french.dll") + else: + loadLib("english.dll") + assert lib != nil, "Error loading library" + + let greet = cast[GreetFunction](lib.symAddr("greet")) + assert greet != nil, "Error loading 'greet' function from library" + + echo greet() + + unloadLib(lib) -import strutils + +import std/strutils type - LibHandle* = pointer ## a handle to a dynamically loaded library + LibHandle* = pointer ## A handle to a dynamically loaded library. proc loadLib*(path: string, globalSymbols = false): LibHandle {.gcsafe.} - ## loads a library from `path`. Returns nil if the library could not + ## Loads a library from `path`. Returns nil if the library could not ## be loaded. proc loadLib*(): LibHandle {.gcsafe.} - ## gets the handle from the current executable. Returns nil if the + ## Gets the handle from the current executable. Returns nil if the ## library could not be loaded. proc unloadLib*(lib: LibHandle) {.gcsafe.} - ## unloads the library `lib` + ## Unloads the library `lib`. proc raiseInvalidLibrary*(name: cstring) {.noinline, noreturn.} = - ## raises an `EInvalidLibrary` exception. + ## Raises a `LibraryError` exception. raise newException(LibraryError, "could not find symbol: " & $name) proc symAddr*(lib: LibHandle, name: cstring): pointer {.gcsafe.} - ## retrieves the address of a procedure/variable from `lib`. Returns nil + ## Retrieves the address of a procedure/variable from `lib`. Returns nil ## if the symbol could not be found. proc checkedSymAddr*(lib: LibHandle, name: cstring): pointer = - ## retrieves the address of a procedure/variable from `lib`. Raises - ## `EInvalidLibrary` if the symbol could not be found. + ## Retrieves the address of a procedure/variable from `lib`. Raises + ## `LibraryError` if the symbol could not be found. result = symAddr(lib, name) if result == nil: raiseInvalidLibrary(name) proc libCandidates*(s: string, dest: var seq[string]) = - ## given a library name pattern `s` write possible library names to `dest`. + ## Given a library name pattern `s`, write possible library names to `dest`. var le = strutils.find(s, '(') var ri = strutils.find(s, ')', le+1) if le >= 0 and ri > le: @@ -97,9 +86,10 @@ proc libCandidates*(s: string, dest: var seq[string]) = add(dest, s) proc loadLibPattern*(pattern: string, globalSymbols = false): LibHandle = - ## loads a library with name matching `pattern`, similar to what `dlimport` + ## Loads a library with name matching `pattern`, similar to what the `dynlib` ## pragma does. Returns nil if the library could not be loaded. - ## Warning: this proc uses the GC and so cannot be used to load the GC. + ## + ## .. warning:: this proc uses the GC and so cannot be used to load the GC. var candidates = newSeq[string]() libCandidates(pattern, candidates) for c in candidates: @@ -115,7 +105,7 @@ when defined(posix) and not defined(nintendoswitch): # as an emulation layer on top of native functions. # ========================================================================= # - import posix + import std/posix proc loadLib(path: string, globalSymbols = false): LibHandle = let flags = @@ -150,6 +140,32 @@ elif defined(nintendoswitch): proc symAddr(lib: LibHandle, name: cstring): pointer = raise newException(OSError, "symAddr not implemented on Nintendo Switch!") +elif defined(genode): + # + # ========================================================================= + # Not implemented for Genode without POSIX. Raise an error if called. + # ========================================================================= + # + + template raiseErr(prc: string) = + raise newException(OSError, prc & " not implemented, compile with POSIX support") + + proc dlclose(lib: LibHandle) = + raiseErr(OSError, "dlclose") + proc dlopen(path: cstring, mode: int): LibHandle = + raiseErr(OSError, "dlopen") + proc dlsym(lib: LibHandle, name: cstring): pointer = + raiseErr(OSError, "dlsym") + proc loadLib(path: string, global_symbols = false): LibHandle = + raiseErr(OSError, "loadLib") + proc loadLib(): LibHandle = + raiseErr(OSError, "loadLib") + proc unloadLib(lib: LibHandle) = + raiseErr(OSError, "unloadLib") + proc symAddr(lib: LibHandle, name: cstring): pointer = + raiseErr(OSError, "symAddr") + + elif defined(windows) or defined(dos): # # ======================================================================= |