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Diffstat (limited to 'src/util/load_lib.c')
| -rw-r--r-- | src/util/load_lib.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/src/util/load_lib.c b/src/util/load_lib.c new file mode 100644 index 0000000..44e540d --- /dev/null +++ b/src/util/load_lib.c @@ -0,0 +1,146 @@ +/*++ +/* NAME +/* load_lib 3 +/* SUMMARY +/* library loading wrappers +/* SYNOPSIS +/* #include <load_lib.h> +/* +/* void load_library_symbols(const char *, LIB_FN *, LIB_DP *); +/* const char *libname; +/* LIB_FN *libfuncs; +/* LIB_DP *libdata; +/* DESCRIPTION +/* load_library_symbols() loads the specified shared object +/* and looks up the function or data pointers for the specified +/* symbols. All errors are fatal. +/* +/* Arguments: +/* .IP libname +/* shared-library pathname. +/* .IP libfuncs +/* Array of LIB_FN structures. The last name member must be null. +/* .IP libdata +/* Array of LIB_DP structures. The last name member must be null. +/* SEE ALSO +/* msg(3) diagnostics interface +/* DIAGNOSTICS +/* Problems are reported via the msg(3) diagnostics routines: +/* library not found, symbols not found, other fatal errors. +/* LICENSE +/* .ad +/* .fi +/* The Secure Mailer license must be distributed with this software. +/* AUTHOR(S) +/* LaMont Jones +/* Hewlett-Packard Company +/* 3404 Harmony Road +/* Fort Collins, CO 80528, USA +/* +/* Wietse Venema +/* IBM T.J. Watson Research +/* P.O. Box 704 +/* Yorktown Heights, NY 10598, USA +/*--*/ + + /* + * System libraries. + */ +#include "sys_defs.h" +#include <stdlib.h> +#include <stddef.h> +#include <string.h> +#ifdef USE_DYNAMIC_MAPS +#if defined(HAS_DLOPEN) +#include <dlfcn.h> +#elif defined(HAS_SHL_LOAD) +#include <dl.h> +#else +#error "USE_DYNAMIC_LIBS requires HAS_DLOPEN or HAS_SHL_LOAD" +#endif + + /* + * Utility library. + */ +#include <msg.h> +#include <load_lib.h> + +/* load_library_symbols - load shared library and look up symbols */ + +void load_library_symbols(const char *libname, LIB_FN *libfuncs, + LIB_DP *libdata) +{ + static const char myname[] = "load_library_symbols"; + LIB_FN *fn; + LIB_DP *dp; + +#if defined(HAS_DLOPEN) + void *handle; + char *emsg; + + /* + * XXX This is basically how FreeBSD dlfunc() silences a compiler warning + * about a data/function pointer conversion. The solution below is non- + * portable: it assumes that both data and function pointers are the same + * in size, and that both have the same representation. + */ + union { + void *dptr; /* data pointer */ + void (*fptr) (void); /* function pointer */ + } non_portable_union; + + if ((handle = dlopen(libname, RTLD_NOW)) == 0) { + emsg = dlerror(); + msg_fatal("%s: dlopen failure loading %s: %s", myname, libname, + emsg ? emsg : "don't know why"); + } + if (libfuncs) { + for (fn = libfuncs; fn->name; fn++) { + if ((non_portable_union.dptr = dlsym(handle, fn->name)) == 0) { + emsg = dlerror(); + msg_fatal("%s: dlsym failure looking up %s in %s: %s", myname, + fn->name, libname, emsg ? emsg : "don't know why"); + } + fn->fptr = non_portable_union.fptr; + if (msg_verbose > 1) + msg_info("loaded %s = %p", fn->name, non_portable_union.dptr); + } + } + if (libdata) { + for (dp = libdata; dp->name; dp++) { + if ((dp->dptr = dlsym(handle, dp->name)) == 0) { + emsg = dlerror(); + msg_fatal("%s: dlsym failure looking up %s in %s: %s", myname, + dp->name, libname, emsg ? emsg : "don't know why"); + } + if (msg_verbose > 1) + msg_info("loaded %s = %p", dp->name, dp->dptr); + } + } +#elif defined(HAS_SHL_LOAD) + shl_t handle; + + handle = shl_load(libname, BIND_IMMEDIATE, 0); + + if (libfuncs) { + for (fn = libfuncs; fn->name; fn++) { + if (shl_findsym(&handle, fn->name, TYPE_PROCEDURE, &fn->fptr) != 0) + msg_fatal("%s: shl_findsym failure looking up %s in %s: %m", + myname, fn->name, libname); + if (msg_verbose > 1) + msg_info("loaded %s = %p", fn->name, (void *) fn->fptr); + } + } + if (libdata) { + for (dp = libdata; dp->name; dp++) { + if (shl_findsym(&handle, dp->name, TYPE_DATA, &dp->dptr) != 0) + msg_fatal("%s: shl_findsym failure looking up %s in %s: %m", + myname, dp->name, libname); + if (msg_verbose > 1) + msg_info("loaded %s = %p", dp->name, dp->dptr); + } + } +#endif +} + +#endif |