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Diffstat (limited to 'nsprpub/pr/include/prlink.h')
| -rw-r--r-- | nsprpub/pr/include/prlink.h | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/nsprpub/pr/include/prlink.h b/nsprpub/pr/include/prlink.h new file mode 100644 index 0000000000..0e38effaf7 --- /dev/null +++ b/nsprpub/pr/include/prlink.h @@ -0,0 +1,230 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef prlink_h___ +#define prlink_h___ + +/* +** API to static and dynamic linking. +*/ +#include "prtypes.h" + +PR_BEGIN_EXTERN_C + +typedef struct PRLibrary PRLibrary; + +typedef struct PRStaticLinkTable { + const char *name; + void (*fp)(void); +} PRStaticLinkTable; + +/* +** Change the default library path to the given string. The string is +** copied. This call will fail if it runs out of memory. +** +** The string provided as 'path' is copied. The caller can do whatever is +** convenient with the argument when the function is complete. +*/ +NSPR_API(PRStatus) PR_SetLibraryPath(const char *path); + +/* +** Return a character string which contains the path used to search for +** dynamically loadable libraries. +** +** The returned value is basically a copy of a PR_SetLibraryPath(). +** The storage is allocated by the runtime and becomes the responsibilty +** of the caller. +*/ +NSPR_API(char*) PR_GetLibraryPath(void); + +/* +** Given a directory name "dir" and a library name "lib" construct a full +** path name that will refer to the actual dynamically loaded +** library. This does not test for existance of said file, it just +** constructs the full filename. The name constructed is system dependent +** and prepared for PR_LoadLibrary. The result must be free'd when the +** caller is done with it. +** +** The storage for the result is allocated by the runtime and becomes the +** responsibility of the caller. +*/ +NSPR_API(char*) PR_GetLibraryName(const char *dir, const char *lib); + +/* +** +** Free the memory allocated, for the caller, by PR_GetLibraryName +*/ +NSPR_API(void) PR_FreeLibraryName(char *mem); + +/* +** Given a library "name" try to load the library. The argument "name" +** is a machine-dependent name for the library, such as the full pathname +** returned by PR_GetLibraryName. If the library is already loaded, +** this function will avoid loading the library twice. +** +** If the library is loaded successfully, then a pointer to the PRLibrary +** structure representing the library is returned. Otherwise, NULL is +** returned. +** +** This increments the reference count of the library. +*/ +NSPR_API(PRLibrary*) PR_LoadLibrary(const char *name); + +/* +** Each operating system has its preferred way of specifying +** a file in the file system. Most operating systems use +** a pathname. Mac OS Classic, on the other hand, uses the FSSpec +** structure to specify a file. PRLibSpec allows NSPR clients +** to use the type of file specification that is most efficient +** for a particular platform. +** +** On some operating systems such as Mac OS Classic, a shared library +** may contain code fragments that can be individually loaded. +** PRLibSpec also allows NSPR clients to identify a code fragment +** in a library, if code fragments are supported by the OS. +** A code fragment can be specified by name or by an integer index. +** +** Right now PRLibSpec supports four types of library specification: +** a pathname in the native character encoding, a Mac code fragment +** by name, a Mac code fragment by index, and a UTF-16 pathname. +*/ + +typedef enum PRLibSpecType { + PR_LibSpec_Pathname, + PR_LibSpec_MacNamedFragment, /* obsolete (for Mac OS Classic) */ + PR_LibSpec_MacIndexedFragment, /* obsolete (for Mac OS Classic) */ + PR_LibSpec_PathnameU /* supported only on Win32 */ +} PRLibSpecType; + +struct FSSpec; /* Mac OS Classic FSSpec */ + +typedef struct PRLibSpec { + PRLibSpecType type; + union { + /* if type is PR_LibSpec_Pathname */ + const char *pathname; + + /* if type is PR_LibSpec_MacNamedFragment */ + struct { + const struct FSSpec *fsspec; + const char *name; + } mac_named_fragment; /* obsolete (for Mac OS Classic) */ + + /* if type is PR_LibSpec_MacIndexedFragment */ + struct { + const struct FSSpec *fsspec; + PRUint32 index; + } mac_indexed_fragment; /* obsolete (for Mac OS Classic) */ + + /* if type is PR_LibSpec_PathnameU */ + const PRUnichar *pathname_u; /* supported only on Win32 */ + } value; +} PRLibSpec; + +/* +** The following bit flags may be or'd together and passed +** as the 'flags' argument to PR_LoadLibraryWithFlags. +** Flags not supported by the underlying OS are ignored. +*/ + +#define PR_LD_LAZY 0x1 /* equivalent to RTLD_LAZY on Unix */ +#define PR_LD_NOW 0x2 /* equivalent to RTLD_NOW on Unix */ +#define PR_LD_GLOBAL 0x4 /* equivalent to RTLD_GLOBAL on Unix */ +#define PR_LD_LOCAL 0x8 /* equivalent to RTLD_LOCAL on Unix */ +/* The following is equivalent to LOAD_WITH_ALTERED_SEARCH_PATH on Windows */ +#define PR_LD_ALT_SEARCH_PATH 0x10 +/* 0x8000 reserved for NSPR internal use */ + +/* +** Load the specified library, in the manner specified by 'flags'. +*/ + +NSPR_API(PRLibrary *) +PR_LoadLibraryWithFlags( + PRLibSpec libSpec, /* the shared library */ + PRIntn flags /* flags that affect the loading */ +); + +/* +** Unload a previously loaded library. If the library was a static +** library then the static link table will no longer be referenced. The +** associated PRLibrary object is freed. +** +** PR_FAILURE is returned if the library cannot be unloaded. +** +** This function decrements the reference count of the library. +*/ +NSPR_API(PRStatus) PR_UnloadLibrary(PRLibrary *lib); + +/* +** Given the name of a procedure, return the address of the function that +** implements the procedure, or NULL if no such function can be +** found. This does not find symbols in the main program (the ".exe"); +** use PR_LoadStaticLibrary to register symbols in the main program. +** +** This function does not modify the reference count of the library. +*/ +NSPR_API(void*) PR_FindSymbol(PRLibrary *lib, const char *name); + +/* +** Similar to PR_FindSymbol, except that the return value is a pointer to +** a function, and not a pointer to void. Casting between a data pointer +** and a function pointer is not portable according to the C standard. +** Any function pointer can be cast to any other function pointer. +** +** This function does not modify the reference count of the library. +*/ +typedef void (*PRFuncPtr)(void); +NSPR_API(PRFuncPtr) PR_FindFunctionSymbol(PRLibrary *lib, const char *name); + +/* +** Finds a symbol in one of the currently loaded libraries. Given the +** name of a procedure, return the address of the function that +** implements the procedure, and return the library that contains that +** symbol, or NULL if no such function can be found. This does not find +** symbols in the main program (the ".exe"); use PR_AddStaticLibrary to +** register symbols in the main program. +** +** This increments the reference count of the library. +*/ +NSPR_API(void*) PR_FindSymbolAndLibrary(const char *name, + PRLibrary* *lib); + +/* +** Similar to PR_FindSymbolAndLibrary, except that the return value is +** a pointer to a function, and not a pointer to void. Casting between a +** data pointer and a function pointer is not portable according to the C +** standard. Any function pointer can be cast to any other function pointer. +** +** This increments the reference count of the library. +*/ +NSPR_API(PRFuncPtr) PR_FindFunctionSymbolAndLibrary(const char *name, + PRLibrary* *lib); + +/* +** Register a static link table with the runtime under the name +** "name". The symbols present in the static link table will be made +** available to PR_FindSymbol. If "name" is null then the symbols will be +** made available to the library which represents the executable. The +** tables are not copied. +** +** Returns the library object if successful, null otherwise. +** +** This increments the reference count of the library. +*/ +NSPR_API(PRLibrary*) PR_LoadStaticLibrary( + const char *name, const PRStaticLinkTable *table); + +/* +** Return the pathname of the file that the library "name" was loaded +** from. "addr" is the address of a function defined in the library. +** +** The caller is responsible for freeing the result with PR_Free. +*/ +NSPR_API(char *) PR_GetLibraryFilePathname(const char *name, PRFuncPtr addr); + +PR_END_EXTERN_C + +#endif /* prlink_h___ */ |