diff options
Diffstat (limited to 'tcl8.6/unix/tclLoadDl.c')
-rw-r--r-- | tcl8.6/unix/tclLoadDl.c | 274 |
1 files changed, 274 insertions, 0 deletions
diff --git a/tcl8.6/unix/tclLoadDl.c b/tcl8.6/unix/tclLoadDl.c new file mode 100644 index 0000000..aec071c --- /dev/null +++ b/tcl8.6/unix/tclLoadDl.c @@ -0,0 +1,274 @@ +/* + * tclLoadDl.c -- + * + * This procedure provides a version of the TclLoadFile that works with + * the "dlopen" and "dlsym" library procedures for dynamic loading. + * + * Copyright (c) 1995-1997 Sun Microsystems, Inc. + * + * See the file "license.terms" for information on usage and redistribution + * of this file, and for a DISCLAIMER OF ALL WARRANTIES. + */ + +#include "tclInt.h" +#ifdef NO_DLFCN_H +# include "../compat/dlfcn.h" +#else +# include <dlfcn.h> +#endif + +/* + * In some systems, like SunOS 4.1.3, the RTLD_NOW flag isn't defined and this + * argument to dlopen must always be 1. The RTLD_LOCAL flag doesn't exist on + * some platforms; if it doesn't exist, set it to 0 so it has no effect. + * See [Bug #3216070] + */ + +#ifndef RTLD_NOW +# define RTLD_NOW 1 +#endif + +#ifndef RTLD_LOCAL +# define RTLD_LOCAL 0 +#endif + +/* + * Static procedures defined within this file. + */ + +static void * FindSymbol(Tcl_Interp *interp, + Tcl_LoadHandle loadHandle, const char *symbol); +static void UnloadFile(Tcl_LoadHandle loadHandle); + +/* + *--------------------------------------------------------------------------- + * + * TclpDlopen -- + * + * Dynamically loads a binary code file into memory and returns a handle + * to the new code. + * + * Results: + * A standard Tcl completion code. If an error occurs, an error message + * is left in the interp's result. + * + * Side effects: + * New code suddenly appears in memory. + * + *--------------------------------------------------------------------------- + */ + +int +TclpDlopen( + Tcl_Interp *interp, /* Used for error reporting. */ + Tcl_Obj *pathPtr, /* Name of the file containing the desired + * code (UTF-8). */ + Tcl_LoadHandle *loadHandle, /* Filled with token for dynamically loaded + * file which will be passed back to + * (*unloadProcPtr)() to unload the file. */ + Tcl_FSUnloadFileProc **unloadProcPtr, + /* Filled with address of Tcl_FSUnloadFileProc + * function which should be used for this + * file. */ + int flags) +{ + void *handle; + Tcl_LoadHandle newHandle; + const char *native; + int dlopenflags = 0; + + /* + * First try the full path the user gave us. This is particularly + * important if the cwd is inside a vfs, and we are trying to load using a + * relative path. + */ + + native = Tcl_FSGetNativePath(pathPtr); + /* + * Use (RTLD_NOW|RTLD_LOCAL) as default, see [Bug #3216070] + */ + if (flags & TCL_LOAD_GLOBAL) { + dlopenflags |= RTLD_GLOBAL; + } else { + dlopenflags |= RTLD_LOCAL; + } + if (flags & TCL_LOAD_LAZY) { + dlopenflags |= RTLD_LAZY; + } else { + dlopenflags |= RTLD_NOW; + } + handle = dlopen(native, dlopenflags); + if (handle == NULL) { + /* + * Let the OS loader examine the binary search path for whatever + * string the user gave us which hopefully refers to a file on the + * binary path. + */ + + Tcl_DString ds; + const char *fileName = Tcl_GetString(pathPtr); + + native = Tcl_UtfToExternalDString(NULL, fileName, -1, &ds); + /* + * Use (RTLD_NOW|RTLD_LOCAL) as default, see [Bug #3216070] + */ + handle = dlopen(native, dlopenflags); + Tcl_DStringFree(&ds); + } + + if (handle == NULL) { + /* + * Write the string to a variable first to work around a compiler bug + * in the Sun Forte 6 compiler. [Bug 1503729] + */ + + const char *errorStr = dlerror(); + + if (interp) { + Tcl_SetObjResult(interp, Tcl_ObjPrintf( + "couldn't load file \"%s\": %s", + Tcl_GetString(pathPtr), errorStr)); + } + return TCL_ERROR; + } + newHandle = ckalloc(sizeof(*newHandle)); + newHandle->clientData = handle; + newHandle->findSymbolProcPtr = &FindSymbol; + newHandle->unloadFileProcPtr = &UnloadFile; + *unloadProcPtr = &UnloadFile; + *loadHandle = newHandle; + + return TCL_OK; +} + +/* + *---------------------------------------------------------------------- + * + * FindSymbol -- + * + * Looks up a symbol, by name, through a handle associated with a + * previously loaded piece of code (shared library). + * + * Results: + * Returns a pointer to the function associated with 'symbol' if it is + * found. Otherwise returns NULL and may leave an error message in the + * interp's result. + * + *---------------------------------------------------------------------- + */ + +static void * +FindSymbol( + Tcl_Interp *interp, /* Place to put error messages. */ + Tcl_LoadHandle loadHandle, /* Value from TcpDlopen(). */ + const char *symbol) /* Symbol to look up. */ +{ + const char *native; /* Name of the library to be loaded, in + * system encoding */ + Tcl_DString newName, ds; /* Buffers for converting the name to + * system encoding and prepending an + * underscore*/ + void *handle = (void *) loadHandle->clientData; + /* Native handle to the loaded library */ + void *proc; /* Address corresponding to the resolved + * symbol */ + + /* + * Some platforms still add an underscore to the beginning of symbol + * names. If we can't find a name without an underscore, try again with + * the underscore. + */ + + native = Tcl_UtfToExternalDString(NULL, symbol, -1, &ds); + proc = dlsym(handle, native); /* INTL: Native. */ + if (proc == NULL) { + Tcl_DStringInit(&newName); + TclDStringAppendLiteral(&newName, "_"); + native = Tcl_DStringAppend(&newName, native, -1); + proc = dlsym(handle, native); /* INTL: Native. */ + Tcl_DStringFree(&newName); + } + Tcl_DStringFree(&ds); + if (proc == NULL) { + const char *errorStr = dlerror(); + + if (interp) { + if (!errorStr) { + errorStr = "unknown"; + } + Tcl_SetObjResult(interp, Tcl_ObjPrintf( + "cannot find symbol \"%s\": %s", symbol, errorStr)); + Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "LOAD_SYMBOL", symbol, + NULL); + } + } + return proc; +} + +/* + *---------------------------------------------------------------------- + * + * UnloadFile -- + * + * Unloads a dynamically loaded binary code file from memory. Code + * pointers in the formerly loaded file are no longer valid after calling + * this function. + * + * Results: + * None. + * + * Side effects: + * Code removed from memory. + * + *---------------------------------------------------------------------- + */ + +static void +UnloadFile( + Tcl_LoadHandle loadHandle) /* loadHandle returned by a previous call to + * TclpDlopen(). The loadHandle is a token + * that represents the loaded file. */ +{ + void *handle = loadHandle->clientData; + + dlclose(handle); + ckfree(loadHandle); +} + +/* + *---------------------------------------------------------------------- + * + * TclGuessPackageName -- + * + * If the "load" command is invoked without providing a package name, + * this procedure is invoked to try to figure it out. + * + * Results: + * Always returns 0 to indicate that we couldn't figure out a package + * name; generic code will then try to guess the package from the file + * name. A return value of 1 would have meant that we figured out the + * package name and put it in bufPtr. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +TclGuessPackageName( + const char *fileName, /* Name of file containing package (already + * translated to local form if needed). */ + Tcl_DString *bufPtr) /* Initialized empty dstring. Append package + * name to this if possible. */ +{ + return 0; +} + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |