Sun Aug 6 15:10:13 2006

Asterisk developer's documentation

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dlfcn.c File Reference

#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdarg.h>
#include <limits.h>
#include <mach-o/dyld.h>
#include <mach-o/nlist.h>
#include <mach-o/getsect.h>
#include "asterisk/dlfcn-compat.h"

Include dependency graph for dlfcn.c:

Go to the source code of this file.

Defines
#define	__BSD_VISIBLE   1
#define	DL_IN_LIST   0x01
#define	dl_restrict   __restrict
#define	ERR_STR_LEN   251
#define	LC_LOAD_WEAK_DYLIB   (0x18 | LC_REQ_DYLD)
#define	LC_REQ_DYLD   0x80000000
#define	MAGIC_DYLIB_MOD   ((NSModule) 'DYMO')
#define	MAGIC_DYLIB_OFI   ((NSObjectFileImage) 'DYOF')
#define	MAX_SEARCH_PATHS   32
#define	NSADDIMAGE_OPTION_RETURN_ON_ERROR   0x1
#define	NSADDIMAGE_OPTION_RETURN_ONLY_IF_LOADED   0x4
#define	NSLOOKUPSYMBOLINIMAGE_OPTION_BIND   0x0
#define	NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR   0x4
#define	RTLD_SELF   ((void *) -3)
Functions
static struct dlstatus *	allocStatus (void)
static void	debug (const char *fmt,...)
int	dladdr (const void *dl_restrict p, Dl_info *dl_restrict info)
int	dlclose (void *handle)
static void	dlcompat_cleanup (void)
static void	dlcompat_init_func (void)
const char *	dlerror (void)
static void	dlerrorfree (void *data)
void *	dlopen (const char *path, int mode)
void *	dlsym (void *dl_restrict handle, const char *dl_restrict symbol)
static void *	dlsymIntern (struct dlstatus *dls, const char *symbol, int canSetError)
static void	dolock (void)
static void	dounlock (void)
static const char *	dyld_error_str (void)
static void	error (const char *str,...)
static const struct stat *	findFile (const char *file, const char **fullPath)
static const char *	get_lib_name (const struct mach_header *mh)
static const struct mach_header *	get_mach_header_from_NSModule (NSModule *mod)
static const char *	getFullPath (int i, const char *file)
static const char *	getSearchPath (int i)
static const struct mach_header *	image_for_address (const void *address)
static void	insertStatus (struct dlstatus *dls, const struct stat *sbuf)
static int	isFlagSet (int mode, int flag)
static int	isValidStatus (struct dlstatus *status)
static struct dlstatus *	loadModule (const char *path, const struct stat *sbuf, int mode)
static struct dlstatus *	lookupStatus (const struct stat *sbuf)
static const struct mach_header *	my_find_image (const char *name)
static int	promoteLocalToGlobal (struct dlstatus *dls)
static void *	reference (struct dlstatus *dls, int mode)
static void	resetdlerror (void)
static const char *	safegetenv (const char *s)
static NSSymbol *	search_linked_libs (const struct mach_header *mh, const char *symbol)
static const char *	searchList (void)
static void	warning (const char *str)
Variables
static pthread_mutex_t	dlcompat_mutex
static pthread_key_t	dlerror_key
static const struct mach_header *(*	dyld_NSAddImage )(const char *, unsigned long)=0
static int(*	dyld_NSIsSymbolNameDefinedInImage )(const struct mach_header *, const char *)=0
static NSSymbol(*	dyld_NSLookupSymbolInImage )(const struct mach_header *, const char *, unsigned long)=0
static struct dlstatus	mainStatus = { 0, MAGIC_DYLIB_MOD, NULL, -1, RTLD_GLOBAL, 0, 0, 0 }
static struct dlstatus *	stqueue = &mainStatus

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Define Documentation

#define __BSD_VISIBLE   1

Definition at line 48 of file dlfcn.c.

#define DL_IN_LIST   0x01

Definition at line 102 of file dlfcn.c. Referenced by insertStatus(), and loadModule().

#define dl_restrict   __restrict

Definition at line 54 of file dlfcn.c.

#define ERR_STR_LEN   251

Definition at line 92 of file dlfcn.c. Referenced by error().

#define LC_LOAD_WEAK_DYLIB   (0x18 | LC_REQ_DYLD)

Definition at line 58 of file dlfcn.c. Referenced by search_linked_libs().

#define LC_REQ_DYLD   0x80000000

Definition at line 65 of file dlfcn.c.

#define MAGIC_DYLIB_MOD   ((NSModule) 'DYMO')

Definition at line 99 of file dlfcn.c. Referenced by dlclose(), dlsymIntern(), loadModule(), promoteLocalToGlobal(), and reference().

#define MAGIC_DYLIB_OFI   ((NSObjectFileImage) 'DYOF')

Definition at line 98 of file dlfcn.c. Referenced by loadModule().

#define MAX_SEARCH_PATHS   32

Definition at line 95 of file dlfcn.c. Referenced by getSearchPath().

#define NSADDIMAGE_OPTION_RETURN_ON_ERROR   0x1

Definition at line 71 of file dlfcn.c. Referenced by loadModule(), and my_find_image().

#define NSADDIMAGE_OPTION_RETURN_ONLY_IF_LOADED   0x4

Definition at line 68 of file dlfcn.c. Referenced by my_find_image().

#define NSLOOKUPSYMBOLINIMAGE_OPTION_BIND   0x0

Definition at line 74 of file dlfcn.c. Referenced by dlsymIntern(), and search_linked_libs().

#define NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR   0x4

Definition at line 77 of file dlfcn.c. Referenced by dlsymIntern(), and search_linked_libs().

#define RTLD_SELF   ((void *) -3)

Referenced by dlsymIntern().

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Function Documentation

static struct dlstatus * allocStatus (  void   )  [static]

Definition at line 428 of file dlfcn.c. References malloc, dlstatus::module, and dlstatus::next. Referenced by loadModule(). { struct dlstatus *dls; #ifdef REUSE_STATUS dls = stqueue; while (dls && dls->module) dls = dls->next; if (!dls) #endif dls = malloc(sizeof(*dls)); dls->flags = 0; return dls; }

static void debug (  const char *  fmt,   ... )  [static]

Definition at line 183 of file dlfcn.c. { #if DEBUG > 1 va_list arg; va_start(arg, fmt); fprintf(stderr, "DLDEBUG: "); vfprintf(stderr, fmt, arg); fprintf(stderr, "\n"); fflush(stderr); va_end(arg); #endif }

int dladdr (  const void *dl_restrict  p, Dl_info *dl_restrict  info )

Definition at line 1167 of file dlfcn.c. References debug, dolock(), dounlock(), and resetdlerror(). { /* FIXME: USe the routine image_for_address. */ unsigned long i; unsigned long j; unsigned long count = _dyld_image_count(); struct mach_header *mh = 0; struct load_command *lc = 0; unsigned long addr = NULL; unsigned long table_off = (unsigned long)0; int found = 0; if (!info) return 0; dolock(); resetdlerror(); info->dli_fname = 0; info->dli_fbase = 0; info->dli_sname = 0; info->dli_saddr = 0; /* Some of this was swiped from code posted by Douglas Davidson <ddavidso AT apple DOT com> * to darwin-development AT lists DOT apple DOT com and slightly modified */ for (i = 0; i < count; i++) { addr = (unsigned long)p - _dyld_get_image_vmaddr_slide(i); mh = _dyld_get_image_header(i); if (mh) { lc = (struct load_command *)((char *)mh + sizeof(struct mach_header)); for (j = 0; j < mh->ncmds; j++, lc = (struct load_command *)((char *)lc + lc->cmdsize)) { if (LC_SEGMENT == lc->cmd && addr >= ((struct segment_command *)lc)->vmaddr && addr < ((struct segment_command *)lc)->vmaddr + ((struct segment_command *)lc)->vmsize) { info->dli_fname = _dyld_get_image_name(i); info->dli_fbase = (void *)mh; found = 1; break; } } if (found) break; } } if (!found) { dounlock(); return 0; } lc = (struct load_command *)((char *)mh + sizeof(struct mach_header)); for (j = 0; j < mh->ncmds; j++, lc = (struct load_command *)((char *)lc + lc->cmdsize)) { if (LC_SEGMENT == lc->cmd) { if (!strcmp(((struct segment_command *)lc)->segname, "__LINKEDIT")) break; } } table_off = ((unsigned long)((struct segment_command *)lc)->vmaddr) - ((unsigned long)((struct segment_command *)lc)->fileoff) + _dyld_get_image_vmaddr_slide(i); debug("table off %x", table_off); lc = (struct load_command *)((char *)mh + sizeof(struct mach_header)); for (j = 0; j < mh->ncmds; j++, lc = (struct load_command *)((char *)lc + lc->cmdsize)) { if (LC_SYMTAB == lc->cmd) { struct nlist *symtable = (struct nlist *)(((struct symtab_command *)lc)->symoff + table_off); unsigned long numsyms = ((struct symtab_command *)lc)->nsyms; struct nlist *nearest = NULL; unsigned long diff = 0xffffffff; unsigned long strtable = (unsigned long)(((struct symtab_command *)lc)->stroff + table_off); debug("symtable %x", symtable); for (i = 0; i < numsyms; i++) { /* Ignore the following kinds of Symbols */ if ((!symtable->n_value) /* Undefined */ || (symtable->n_type >= N_PEXT) /* Debug symbol */ || (!(symtable->n_type & N_EXT)) /* Local Symbol */ ) { symtable++; continue; } if ((addr >= symtable->n_value) && (diff >= (symtable->n_value - addr))) { diff = (unsigned long)symtable->n_value - addr; nearest = symtable; } symtable++; } if (nearest) { info->dli_saddr = nearest->n_value + ((void *)p - addr); info->dli_sname = (char *)(strtable + nearest->n_un.n_strx); } } } dounlock(); return 1; }

int dlclose (  void *  handle  )

Definition at line 1041 of file dlfcn.c. References debug, dlsymIntern(), dolock(), dounlock(), error(), get_lib_name(), get_mach_header_from_NSModule(), isFlagSet(), isValidStatus(), dlstatus::lib, MAGIC_DYLIB_MOD, dlstatus::mode, dlstatus::module, name, dlstatus::refs, resetdlerror(), RTLD_NODELETE, and warning(). Referenced by __load_resource(), and ast_unload_resource(). { struct dlstatus *dls = handle; dolock(); resetdlerror(); if (!isValidStatus(dls)) { goto dlcloseerror; } if (dls->module == MAGIC_DYLIB_MOD) { const char *name; if (!dls->lib) { name = "global context"; } else { name = get_lib_name(dls->lib); } warning("trying to close a .dylib!"); error("Not closing \"%s\" - dynamic libraries cannot be closed", name); goto dlcloseerror; } if (!dls->module) { error("module already closed"); goto dlcloseerror; } if (dls->refs == 1) { unsigned long options = 0; void (*fini) (void); if ((fini = dlsymIntern(dls, "__fini", 0))) { debug("calling _fini()"); fini(); } #ifdef __ppc__ options |= NSUNLINKMODULE_OPTION_RESET_LAZY_REFERENCES; #endif #if 1 /* Currently, if a module contains c++ static destructors and it is unloaded, we * get a segfault in atexit(), due to compiler and dynamic loader differences of * opinion, this works around that. * I really need a way to figure out from code if this is still necessary. */ if ((const struct section *)NULL != getsectbynamefromheader(get_mach_header_from_NSModule(dls->module), "__DATA", "__mod_term_func")) { options |= NSUNLINKMODULE_OPTION_KEEP_MEMORY_MAPPED; } #endif #ifdef RTLD_NODELETE if (isFlagSet(dls->mode, RTLD_NODELETE)) options |= NSUNLINKMODULE_OPTION_KEEP_MEMORY_MAPPED; #endif if (!NSUnLinkModule(dls->module, options)) { error("unable to unlink module"); goto dlcloseerror; } dls->refs--; dls->module = 0; /* Note: the dlstatus struct dls is neither removed from the list * nor is the memory it occupies freed. This shouldn't pose a * problem in mostly all cases, though. */ } dounlock(); return 0; dlcloseerror: dounlock(); return 1; }

static void dlcompat_cleanup (  void   )  [static]

Definition at line 824 of file dlfcn.c. References dlcompat_mutex, dlerror_key, free, getSearchPath(), dlstatus::next, pthread_mutex_destroy, and searchList(). Referenced by dlcompat_init_func(). { struct dlstatus *dls; struct dlstatus *next; char *data; data = (char *)searchList(); if ( data ) free( data ); data = (char *)getSearchPath(-1); if ( data ) free( data ); pthread_mutex_destroy(&dlcompat_mutex); pthread_key_delete(dlerror_key); next = stqueue; while (next && (next != &mainStatus)) { dls = next; next = dls->next; free(dls); } }

static void dlcompat_init_func (  void   )  [static]

Definition at line 801 of file dlfcn.c. References dlcompat_cleanup(), dlcompat_mutex, dlerror_key, dlerrorfree(), dyld_NSAddImage, dyld_NSIsSymbolNameDefinedInImage, dyld_NSLookupSymbolInImage, and pthread_mutex_init. Referenced by dlopen(). { static int inited = 0; if (!inited) { inited = 1; _dyld_func_lookup("__dyld_NSAddImage", (unsigned long *)&dyld_NSAddImage); _dyld_func_lookup("__dyld_NSIsSymbolNameDefinedInImage", (unsigned long *)&dyld_NSIsSymbolNameDefinedInImage); _dyld_func_lookup("__dyld_NSLookupSymbolInImage", (unsigned long *)&dyld_NSLookupSymbolInImage); if (pthread_mutex_init(&dlcompat_mutex, NULL)) exit(1); if (pthread_key_create(&dlerror_key, &dlerrorfree)) exit(1); /* And be neat and tidy and clean up after ourselves */ atexit(dlcompat_cleanup); } }

const char* dlerror (  void   )

Definition at line 1119 of file dlfcn.c. References dlerror_key, dlthread::errset, and dlthread::errstr. Referenced by __load_resource(). { struct dlthread *tss; char * err_str; tss = pthread_getspecific(dlerror_key); err_str = tss->errstr; tss = pthread_getspecific(dlerror_key); if (tss->errset == 0) return 0; tss->errset = 0; return (err_str ); }

static void dlerrorfree (  void *  data  )  [static]

Definition at line 853 of file dlfcn.c. References free. Referenced by dlcompat_init_func(). { free(data); }

void* dlopen (  const char *  path, int  mode )

Definition at line 897 of file dlfcn.c. References dlcompat_init_func(), dolock(), dounlock(), error(), findFile(), isFlagSet(), loadModule(), lookupStatus(), reference(), dlstatus::refs, resetdlerror(), RTLD_LAZY, RTLD_NOLOAD, and RTLD_NOW. Referenced by __load_resource(). { const struct stat *sbuf; struct dlstatus *dls; const char *fullPath; dlcompat_init_func(); /* Just in case */ dolock(); resetdlerror(); if (!path) { dls = &mainStatus; goto dlopenok; } if (!(sbuf = findFile(path, &fullPath))) { error("file \"%s\" not found", path); goto dlopenerror; } /* Now checks that it hasn't been closed already */ if ((dls = lookupStatus(sbuf)) && (dls->refs > 0)) { /* debug("status found"); */ dls = reference(dls, mode); goto dlopenok; } #ifdef RTLD_NOLOAD if (isFlagSet(mode, RTLD_NOLOAD)) { error("no existing handle and RTLD_NOLOAD specified"); goto dlopenerror; } #endif if (isFlagSet(mode, RTLD_LAZY) && isFlagSet(mode, RTLD_NOW)) { error("how can I load something both RTLD_LAZY and RTLD_NOW?"); goto dlopenerror; } dls = loadModule(fullPath, sbuf, mode); dlopenok: dounlock(); return (void *)dls; dlopenerror: dounlock(); return NULL; }

void* dlsym (  void *dl_restrict  handle, const char *dl_restrict  symbol )

Definition at line 945 of file dlfcn.c. References dlsymIntern(), dolock(), dounlock(), error(), free, and malloc. Referenced by __load_resource(). { int sym_len = strlen(symbol); void *value = NULL; char *malloc_sym = NULL; dolock(); malloc_sym = malloc(sym_len + 2); if (malloc_sym) { sprintf(malloc_sym, "_%s", symbol); value = dlsymIntern(handle, malloc_sym, 1); free(malloc_sym); } else { error("Unable to allocate memory"); goto dlsymerror; } dounlock(); return value; dlsymerror: dounlock(); return NULL; }

static void * dlsymIntern (  struct dlstatus *  dls, const char *  symbol, int  canSetError )  [static]

Definition at line 560 of file dlfcn.c. References debug, dyld_error_str(), dyld_NSIsSymbolNameDefinedInImage, dyld_NSLookupSymbolInImage, error(), free, get_mach_header_from_NSModule(), image_for_address(), isValidStatus(), dlstatus::lib, MAGIC_DYLIB_MOD, malloc, dlstatus::module, NSLOOKUPSYMBOLINIMAGE_OPTION_BIND, NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR, resetdlerror(), RTLD_DEFAULT, RTLD_NEXT, RTLD_SELF, and search_linked_libs(). Referenced by dlclose(), dlsym(), and loadModule(). { NSSymbol *nssym = 0; void *caller = __builtin_return_address(1); /* Be *very* careful about inlining */ const struct mach_header *caller_mh = 0; const char* savedErrorStr = NULL; resetdlerror(); #ifndef RTLD_SELF #define RTLD_SELF ((void *) -3) #endif if (NULL == dls) dls = RTLD_SELF; if ((RTLD_NEXT == dls) || (RTLD_SELF == dls)) { if (dyld_NSIsSymbolNameDefinedInImage && dyld_NSLookupSymbolInImage) { caller_mh = image_for_address(caller); if (RTLD_SELF == dls) { /* FIXME: We should be using the NSModule api, if SELF is an MH_BUNDLE * But it appears to work anyway, and looking at the code in dyld_libfuncs.c * this is acceptable. */ if (dyld_NSIsSymbolNameDefinedInImage(caller_mh, symbol)) { nssym = dyld_NSLookupSymbolInImage(caller_mh, symbol, NSLOOKUPSYMBOLINIMAGE_OPTION_BIND | NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR); } } if (!nssym) { if (RTLD_SELF == dls) savedErrorStr = dyld_error_str(); nssym = search_linked_libs(caller_mh, symbol); } } else { if (canSetError) error("RTLD_SELF and RTLD_NEXT are not supported"); return NULL; } } if (!nssym) { if (RTLD_DEFAULT == dls) { dls = &mainStatus; } if (!isValidStatus(dls)) return NULL; if (dls->module != MAGIC_DYLIB_MOD) { nssym = NSLookupSymbolInModule(dls->module, symbol); if (!nssym && NSIsSymbolNameDefined(symbol)) { debug("Searching dependencies"); savedErrorStr = dyld_error_str(); nssym = search_linked_libs(get_mach_header_from_NSModule(dls->module), symbol); } } else if (dls->lib && dyld_NSIsSymbolNameDefinedInImage && dyld_NSLookupSymbolInImage) { if (dyld_NSIsSymbolNameDefinedInImage(dls->lib, symbol)) { nssym = dyld_NSLookupSymbolInImage(dls->lib, symbol, NSLOOKUPSYMBOLINIMAGE_OPTION_BIND | NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR); } else if (NSIsSymbolNameDefined(symbol)) { debug("Searching dependencies"); savedErrorStr = dyld_error_str(); nssym = search_linked_libs(dls->lib, symbol); } } else if (dls->module == MAGIC_DYLIB_MOD) { /* Global context, use NSLookupAndBindSymbol */ if (NSIsSymbolNameDefined(symbol)) { /* There doesn't seem to be a return on error option for this call??? this is potentially broken, if binding fails, it will improperly exit the application. */ nssym = NSLookupAndBindSymbol(symbol); } else { if (savedErrorStr) free((char*)savedErrorStr); savedErrorStr = malloc(256); snprintf((char*)savedErrorStr, 256, "Symbol \"%s\" not in global context",symbol); } } } /* Error reporting */ if (!nssym) { if (!savedErrorStr || !strlen(savedErrorStr)) { if (savedErrorStr) free((char*)savedErrorStr); savedErrorStr = malloc(256); snprintf((char*)savedErrorStr, 256,"Symbol \"%s\" not found",symbol); } if (canSetError) { error(savedErrorStr); } else { debug(savedErrorStr); } if (savedErrorStr) free((char*)savedErrorStr); return NULL; } return NSAddressOfSymbol(nssym); }

static void dolock (  void   )  [inline, static]

Definition at line 862 of file dlfcn.c. References dlcompat_mutex, dlerror_key, dlthread::errset, dlthread::lockcnt, malloc, and pthread_mutex_lock. Referenced by dladdr(), dlclose(), dlopen(), and dlsym(). { int err = 0; struct dlthread *tss; tss = pthread_getspecific(dlerror_key); if (!tss) { tss = malloc(sizeof(struct dlthread)); tss->lockcnt = 0; tss->errset = 0; if (pthread_setspecific(dlerror_key, tss)) { fprintf(stderr,"dlcompat: pthread_setspecific failed\n"); exit(1); } } if (!tss->lockcnt) err = pthread_mutex_lock(&dlcompat_mutex); tss->lockcnt = tss->lockcnt +1; if (err) exit(err); }

static void dounlock (  void   )  [inline, static]

Definition at line 885 of file dlfcn.c. References dlcompat_mutex, dlerror_key, dlthread::lockcnt, and pthread_mutex_unlock. Referenced by dladdr(), dlclose(), dlopen(), and dlsym(). { int err = 0; struct dlthread *tss; tss = pthread_getspecific(dlerror_key); tss->lockcnt = tss->lockcnt -1; if (!tss->lockcnt) err = pthread_mutex_unlock(&dlcompat_mutex); if (err) exit(err); }

static const char * dyld_error_str (  void   )  [inline, static]

Definition at line 544 of file dlfcn.c. References malloc. Referenced by dlsymIntern(). { NSLinkEditErrors dylder; int dylderno; const char *dylderrstr; const char *dyldfile; const char* retStr = NULL; NSLinkEditError(&dylder, &dylderno, &dyldfile, &dylderrstr); if (dylderrstr && strlen(dylderrstr)) { retStr = malloc(strlen(dylderrstr) +1); strcpy((char*)retStr,dylderrstr); } return retStr; }

static void error (  const char *  str,   ... )  [static]

Definition at line 196 of file dlfcn.c. References debug, dlerror_key, ERR_STR_LEN, dlthread::errset, and dlthread::errstr. Referenced by append_string(), dlclose(), dlopen(), dlsym(), dlsymIntern(), handle_request(), iax2_hangup(), iax2_write(), isValidStatus(), load_module(), loadModule(), reference(), restart_monitor(), and store_config(). { va_list arg; struct dlthread *tss; char * err_str; va_start(arg, str); tss = pthread_getspecific(dlerror_key); err_str = tss->errstr; strncpy(err_str, "dlcompat: ", ERR_STR_LEN); vsnprintf(err_str + 10, ERR_STR_LEN - 10, str, arg); va_end(arg); debug("ERROR: %s\n", err_str); tss->errset = 1; }

static const struct stat * findFile (  const char *  file, const char **  fullPath )  [static]

Definition at line 359 of file dlfcn.c. References debug, and getFullPath(). Referenced by dlopen(). { int i = 0; static struct stat sbuf; char *fileName; debug("finding file %s", file); *fullPath = file; if (0 == stat(file, &sbuf)) return &sbuf; if (strchr(file, '/')) return 0; /* If the path had a / we don't look in env var places */ fileName = NULL; if (!fileName) fileName = (char *)file; while ((*fullPath = getFullPath(i++, fileName))) { if (0 == stat(*fullPath, &sbuf)) return &sbuf; } ; return 0; }

static const char * get_lib_name (  const struct mach_header *  mh  )  [static]

Definition at line 228 of file dlfcn.c. Referenced by dlclose(). { unsigned long count = _dyld_image_count(); unsigned long i; const char *val = NULL; if (mh) { for (i = 0; i < count; i++) { if (mh == _dyld_get_image_header(i)) { val = _dyld_get_image_name(i); break; } } } return val; }

static const struct mach_header * get_mach_header_from_NSModule (  NSModule *  mod  )  [static]

Definition at line 251 of file dlfcn.c. References debug. Referenced by dlclose(), dlsymIntern(), and loadModule(). { const char *mod_name = NSNameOfModule(mod); struct mach_header *mh = NULL; unsigned long count = _dyld_image_count(); unsigned long i; debug("Module name: %s", mod_name); for (i = 0; i < count; i++) { if (!strcmp(mod_name, _dyld_get_image_name(i))) { mh = _dyld_get_image_header(i); break; } } return mh; }

static const char * getFullPath (  int  i, const char *  file )  [static]

Definition at line 344 of file dlfcn.c. References getSearchPath(). Referenced by findFile(). { static char buf[PATH_MAX]; const char *path = getSearchPath(i); if (path) { snprintf(buf, PATH_MAX, "%s/%s", path, file); } return path ? buf : 0; }

static const char * getSearchPath (  int  i  )  [static]

Definition at line 298 of file dlfcn.c. References calloc, debug, free, list, MAX_SEARCH_PATHS, searchList(), and strsep(). Referenced by dlcompat_cleanup(), and getFullPath(). { static const char *list = 0; static char **path = (char **)0; static int end = 0; static int numsize = MAX_SEARCH_PATHS; static char **tmp; /* So we can call free() in the "destructor" we use i=-1 to return the alloc'd array */ if (i == -1) { return (const char*)path; } if (!path) { path = (char **)calloc(MAX_SEARCH_PATHS, sizeof(char **)); } if (!list && !end) list = searchList(); if (i >= (numsize)) { debug("Increasing size for long PATH"); tmp = (char **)calloc((MAX_SEARCH_PATHS + numsize), sizeof(char **)); if (tmp) { memcpy(tmp, path, sizeof(char **) * numsize); free(path); path = tmp; numsize += MAX_SEARCH_PATHS; } else { return 0; } } while (!path[i] && !end) { path[i] = strsep((char **)&list, ":"); if (path[i][0] == 0) path[i] = 0; end = (list == 0); } return path[i]; }

const struct mach_header * image_for_address (  const void *  address  )  [static]

Definition at line 1135 of file dlfcn.c. Referenced by dlsymIntern(). { unsigned long i; unsigned long j; unsigned long count = _dyld_image_count(); struct mach_header *mh = 0; struct load_command *lc = 0; unsigned long addr = NULL; for (i = 0; i < count; i++) { addr = (unsigned long)address - _dyld_get_image_vmaddr_slide(i); mh = _dyld_get_image_header(i); if (mh) { lc = (struct load_command *)((char *)mh + sizeof(struct mach_header)); for (j = 0; j < mh->ncmds; j++, lc = (struct load_command *)((char *)lc + lc->cmdsize)) { if (LC_SEGMENT == lc->cmd && addr >= ((struct segment_command *)lc)->vmaddr && addr < ((struct segment_command *)lc)->vmaddr + ((struct segment_command *)lc)->vmsize) { goto image_found; } } } mh = 0; } image_found: return mh; }

static void insertStatus (  struct dlstatus *  dls, const struct stat *  sbuf )  [static]

Definition at line 413 of file dlfcn.c. References debug, dlstatus::device, DL_IN_LIST, dlstatus::flags, dlstatus::inode, dlstatus::mode, dlstatus::next, and dlstatus::refs. Referenced by loadModule(). { debug("inserting status"); dls->inode = sbuf->st_ino; dls->device = sbuf->st_dev; dls->refs = 0; dls->mode = 0; if ((dls->flags & DL_IN_LIST) == 0) { dls->next = stqueue; stqueue = dls; dls->flags |= DL_IN_LIST; } }

static int isFlagSet (  int  mode, int  flag )  [inline, static]

Definition at line 398 of file dlfcn.c. Referenced by dlclose(), dlopen(), loadModule(), and reference(). { return (mode & flag) == flag; }

static int isValidStatus (  struct dlstatus *  status  )  [static]

Definition at line 383 of file dlfcn.c. References error(), FALSE, dlstatus::module, dlstatus::next, dlstatus::refs, and TRUE. Referenced by dlclose(), and dlsymIntern(). { /* Walk the list to verify status is contained in it */ struct dlstatus *dls = stqueue; while (dls && status != dls) dls = dls->next; if (dls == 0) error("invalid handle"); else if ((dls->module == 0) || (dls->refs == 0)) error("handle to closed library"); else return TRUE; return FALSE; }

static struct dlstatus * loadModule (  const char *  path, const struct stat *  sbuf, int  mode )  [static]

Definition at line 685 of file dlfcn.c. References allocStatus(), debug, DL_IN_LIST, dlsymIntern(), dyld_NSAddImage, dyld_NSIsSymbolNameDefinedInImage, dyld_NSLookupSymbolInImage, error(), dlstatus::flags, free, get_mach_header_from_NSModule(), insertStatus(), isFlagSet(), dlstatus::lib, lookupStatus(), MAGIC_DYLIB_MOD, MAGIC_DYLIB_OFI, dlstatus::module, NSADDIMAGE_OPTION_RETURN_ON_ERROR, reference(), RTLD_GLOBAL, RTLD_NOW, and warning(). Referenced by dlopen(). { NSObjectFileImage ofi = 0; NSObjectFileImageReturnCode ofirc; struct dlstatus *dls; NSLinkEditErrors ler; int lerno; const char *errstr; const char *file; void (*init) (void); ofirc = NSCreateObjectFileImageFromFile(path, &ofi); switch (ofirc) { case NSObjectFileImageSuccess: break; case NSObjectFileImageInappropriateFile: if (dyld_NSAddImage && dyld_NSIsSymbolNameDefinedInImage && dyld_NSLookupSymbolInImage) { if (!isFlagSet(mode, RTLD_GLOBAL)) { warning("trying to open a .dylib with RTLD_LOCAL"); error("unable to open this file with RTLD_LOCAL"); return NULL; } } else { error("opening this file is unsupported on this system"); return NULL; } break; case NSObjectFileImageFailure: error("object file setup failure"); return NULL; case NSObjectFileImageArch: error("no object for this architecture"); return NULL; case NSObjectFileImageFormat: error("bad object file format"); return NULL; case NSObjectFileImageAccess: error("can't read object file"); return NULL; default: error("unknown error from NSCreateObjectFileImageFromFile()"); return NULL; } dls = lookupStatus(sbuf); if (!dls) { dls = allocStatus(); } if (!dls) { error("unable to allocate memory"); return NULL; } dls->lib = 0; if (ofirc == NSObjectFileImageInappropriateFile) { if ((dls->lib = dyld_NSAddImage(path, NSADDIMAGE_OPTION_RETURN_ON_ERROR))) { debug("Dynamic lib loaded at %ld", dls->lib); ofi = MAGIC_DYLIB_OFI; dls->module = MAGIC_DYLIB_MOD; ofirc = NSObjectFileImageSuccess; /* Although it is possible with a bit of work to modify this so it works and functions with RTLD_NOW, I don't deem it necessary at the moment */ } if (!(dls->module)) { NSLinkEditError(&ler, &lerno, &file, &errstr); if (!errstr || (!strlen(errstr))) error("Can't open this file type"); else error(errstr); if ((dls->flags & DL_IN_LIST) == 0) { free(dls); } return NULL; } } else { dls->module = NSLinkModule(ofi, path, NSLINKMODULE_OPTION_RETURN_ON_ERROR | NSLINKMODULE_OPTION_PRIVATE | (isFlagSet(mode, RTLD_NOW) ? NSLINKMODULE_OPTION_BINDNOW : 0)); NSDestroyObjectFileImage(ofi); if (dls->module) { dls->lib = get_mach_header_from_NSModule(dls->module); } } if (!dls->module) { NSLinkEditError(&ler, &lerno, &file, &errstr); if ((dls->flags & DL_IN_LIST) == 0) { free(dls); } error(errstr); return NULL; } insertStatus(dls, sbuf); dls = reference(dls, mode); if ((init = dlsymIntern(dls, "__init", 0))) { debug("calling _init()"); init(); } return dls; }

static struct dlstatus * lookupStatus (  const struct stat *  sbuf  )  [static]

Definition at line 403 of file dlfcn.c. References debug, dlstatus::device, dlstatus::inode, and dlstatus::next. Referenced by dlopen(), and loadModule(). { struct dlstatus *dls = stqueue; debug("looking for status"); while (dls && ( /* isFlagSet(dls->mode, RTLD_UNSHARED) */ 0 || sbuf->st_dev != dls->device || sbuf->st_ino != dls->inode)) dls = dls->next; return dls; }

static const struct mach_header * my_find_image (  const char *  name  )  [static]

Definition at line 476 of file dlfcn.c. References dyld_NSAddImage, NSADDIMAGE_OPTION_RETURN_ON_ERROR, and NSADDIMAGE_OPTION_RETURN_ONLY_IF_LOADED. Referenced by search_linked_libs(). { const struct mach_header *mh = 0; const char *id = NULL; int i = _dyld_image_count(); int j; mh = (struct mach_header *) dyld_NSAddImage(name, NSADDIMAGE_OPTION_RETURN_ONLY_IF_LOADED | NSADDIMAGE_OPTION_RETURN_ON_ERROR); if (!mh) { for (j = 0; j < i; j++) { id = _dyld_get_image_name(j); if (!strcmp(id, name)) { mh = _dyld_get_image_header(j); break; } } } return mh; }

static int promoteLocalToGlobal (  struct dlstatus *  dls  )  [static]

Definition at line 442 of file dlfcn.c. References debug, MAGIC_DYLIB_MOD, and dlstatus::module. Referenced by reference(). { static int (*p) (NSModule module) = 0; debug("promoting"); if (!p) _dyld_func_lookup("__dyld_NSMakePrivateModulePublic", (unsigned long *)&p); return (dls->module == MAGIC_DYLIB_MOD) || (p && p(dls->module)); }

static void * reference (  struct dlstatus *  dls, int  mode )  [static]

Definition at line 451 of file dlfcn.c. References debug, error(), isFlagSet(), MAGIC_DYLIB_MOD, dlstatus::mode, dlstatus::module, promoteLocalToGlobal(), dlstatus::refs, RTLD_GLOBAL, and warning(). Referenced by dlopen(), and loadModule(). { if (dls) { if (dls->module == MAGIC_DYLIB_MOD && !isFlagSet(mode, RTLD_GLOBAL)) { warning("trying to open a .dylib with RTLD_LOCAL"); error("unable to open a .dylib with RTLD_LOCAL"); return NULL; } if (isFlagSet(mode, RTLD_GLOBAL) && !isFlagSet(dls->mode, RTLD_GLOBAL) && !promoteLocalToGlobal(dls)) { error("unable to promote local module to global"); return NULL; } dls->mode |= mode; dls->refs++; } else debug("reference called with NULL argument"); return dls; }

static void resetdlerror (  void   )  [static]

Definition at line 846 of file dlfcn.c. References dlerror_key, and dlthread::errset. Referenced by dladdr(), dlclose(), dlopen(), and dlsymIntern(). { struct dlthread *tss; tss = pthread_getspecific(dlerror_key); tss->errset = 0; }

static const char * safegetenv (  const char *  s  )  [static]

Definition at line 218 of file dlfcn.c. Referenced by searchList(). { const char *ss = getenv(s); return ss ? ss : ""; }

NSSymbol * search_linked_libs (  const struct mach_header *  mh, const char *  symbol )  [static]

Definition at line 506 of file dlfcn.c. References debug, dyld_NSAddImage, dyld_NSIsSymbolNameDefinedInImage, dyld_NSLookupSymbolInImage, LC_LOAD_WEAK_DYLIB, my_find_image(), n, NSLOOKUPSYMBOLINIMAGE_OPTION_BIND, and NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR. Referenced by dlsymIntern(). { int n; struct load_command *lc = 0; struct mach_header *wh; NSSymbol *nssym = 0; if (dyld_NSAddImage && dyld_NSIsSymbolNameDefinedInImage && dyld_NSLookupSymbolInImage) { lc = (struct load_command *)((char *)mh + sizeof(struct mach_header)); for (n = 0; n < mh->ncmds; n++, lc = (struct load_command *)((char *)lc + lc->cmdsize)) { if ((LC_LOAD_DYLIB == lc->cmd) || (LC_LOAD_WEAK_DYLIB == lc->cmd)) { if ((wh = (struct mach_header *) my_find_image((char *)(((struct dylib_command *)lc)->dylib.name.offset + (char *)lc)))) { if (dyld_NSIsSymbolNameDefinedInImage(wh, symbol)) { nssym = dyld_NSLookupSymbolInImage(wh, symbol, NSLOOKUPSYMBOLINIMAGE_OPTION_BIND | NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR); break; } } } } if ((!nssym) && NSIsSymbolNameDefined(symbol)) { /* I've never seen this debug message...*/ debug("Symbol \"%s\" is defined but was not found", symbol); } } return nssym; }

static const char * searchList (  void   )  [static]

Definition at line 278 of file dlfcn.c. References malloc, and safegetenv(). Referenced by dlcompat_cleanup(), and getSearchPath(). { size_t buf_size; static char *buf=NULL; const char *ldlp = safegetenv("LD_LIBRARY_PATH"); const char *dyldlp = safegetenv("DYLD_LIBRARY_PATH"); const char *stdpath = getenv("DYLD_FALLBACK_LIBRARY_PATH"); if (!stdpath) stdpath = "/usr/local/lib:/lib:/usr/lib"; if (!buf) { buf_size = strlen(ldlp) + strlen(dyldlp) + strlen(stdpath) + 4; buf = malloc(buf_size); snprintf(buf, buf_size, "%s%s%s%s%s%c", dyldlp, (dyldlp[0] ? ":" : ""), ldlp, (ldlp[0] ? ":" : ""), stdpath, '\0'); } return buf; }

static void warning (  const char *  str  )  [static]

Definition at line 211 of file dlfcn.c. Referenced by dlclose(), loadModule(), and reference(). { #if DEBUG > 0 fprintf(stderr, "WARNING: dlcompat: %s\n", str); #endif }

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Variable Documentation

pthread_mutex_t dlcompat_mutex [static]

Definition at line 105 of file dlfcn.c. Referenced by dlcompat_cleanup(), dlcompat_init_func(), dolock(), and dounlock().

pthread_key_t dlerror_key [static]

Definition at line 108 of file dlfcn.c. Referenced by dlcompat_cleanup(), dlcompat_init_func(), dlerror(), dolock(), dounlock(), error(), and resetdlerror().

const struct mach_header*(* dyld_NSAddImage)(const char *, unsigned long)=0 [static]

Definition at line 80 of file dlfcn.c. Referenced by dlcompat_init_func(), loadModule(), my_find_image(), and search_linked_libs().

int(* dyld_NSIsSymbolNameDefinedInImage)(const struct mach_header *, const char *)=0 [static]

Definition at line 81 of file dlfcn.c. Referenced by dlcompat_init_func(), dlsymIntern(), loadModule(), and search_linked_libs().

NSSymbol(* dyld_NSLookupSymbolInImage)(const struct mach_header *, const char *, unsigned long)=0 [static]

Definition at line 83 of file dlfcn.c. Referenced by dlcompat_init_func(), dlsymIntern(), loadModule(), and search_linked_libs().

struct dlstatus mainStatus = { 0, MAGIC_DYLIB_MOD, NULL, -1, RTLD_GLOBAL, 0, 0, 0 } [static]

Definition at line 133 of file dlfcn.c.

struct dlstatus* stqueue = &mainStatus [static]

Definition at line 134 of file dlfcn.c.

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