diff options
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/dl-deps.c | 65 | ||||
| -rw-r--r-- | elf/dl-init.c | 58 | ||||
| -rw-r--r-- | elf/dladdr.c | 2 | ||||
| -rw-r--r-- | elf/dlclose.c | 100 | ||||
| -rw-r--r-- | elf/dlsym.c | 10 | ||||
| -rw-r--r-- | elf/link.h | 10 |
6 files changed, 126 insertions, 119 deletions
diff --git a/elf/dl-deps.c b/elf/dl-deps.c index f87475a670..92403d4110 100644 --- a/elf/dl-deps.c +++ b/elf/dl-deps.c @@ -25,20 +25,33 @@ Cambridge, MA 02139, USA. */ void _dl_map_object_deps (struct link_map *map) { - unsigned int nlist = 1; - struct link_map **list = malloc (sizeof *list); - unsigned int done; + struct list + { + struct link_map *map; + struct list *next; + }; + struct list head, *tailp, *scanp; + unsigned int nlist; /* Start the search list with one element: MAP itself. */ - list[0] = map; + head.map = map; + head.next = NULL; + nlist = 1; + /* Process each element of the search list, loading each of its immediate dependencies and appending them to the list as we step through it. This produces a flat, ordered list that represents a breadth-first search of the dependency tree. */ - for (done = 0; done < nlist; ++done) + for (scanp = tailp = &head; scanp; scanp = scanp->next) { - struct link_map *l = list[done]; + struct link_map *l = scanp->map; + + /* We use `l_reserved' as a mark bit to detect objects we have + already put in the search list and avoid adding duplicate elements + later in the list. */ + l->l_reserved = 1; + if (l->l_info[DT_NEEDED]) { const char *strtab @@ -47,24 +60,42 @@ _dl_map_object_deps (struct link_map *map) for (d = l->l_ld; d->d_tag != DT_NULL; ++d) if (d->d_tag == DT_NEEDED) { - /* Extend the list and put this object on the end. */ - struct link_map **n - = realloc (list, (nlist + 1) * sizeof *list); - if (n) - list = n; + /* Map in the needed object. */ + struct link_map *dep + = _dl_map_object (l, strtab + d->d_un.d_val); + + if (dep->l_reserved) + /* This object is already in the search list we are + building. Don't add a duplicate pointer. Release the + reference just added by _dl_map_object. */ + --dep->l_opencount; else { - free (list); - _dl_signal_error (ENOMEM, map->l_name, - "finding dependencies"); + /* Append DEP to the search list. */ + tailp->next = alloca (sizeof *tailp); + tailp = tailp->next; + tailp->map = dep; + tailp->next = NULL; + ++nlist; } - list[nlist++] = _dl_map_object (l, strtab + d->d_un.d_val); } } } - map->l_searchlist = list; + /* Store the search list we built in the object. It will be used for + searches in the scope of this object. */ + map->l_searchlist = malloc (nlist * sizeof (struct link_map *)); map->l_nsearchlist = nlist; + + nlist = 0; + for (scanp = &head; scanp; scanp = scanp->next) + { + map->l_searchlist[nlist++] = scanp->map; + + /* Now clear all the mark bits we set in the objects on the search list + to avoid duplicates, so the next call starts fresh. */ + scanp->map->l_reserved = 0; + } } @@ -86,7 +117,7 @@ _dl_open (struct link_map *parent, const char *file, int mode) _dl_relocate_object (l, (mode & RTLD_BINDING_MASK) == RTLD_LAZY); /* Run the initializer functions of new objects. */ - while (init = _dl_init_next ()) + while (init = _dl_init_next (new)) (*(void (*) (void)) init) (); return new; diff --git a/elf/dl-init.c b/elf/dl-init.c index 7375c5f782..ee99ce3dec 100644 --- a/elf/dl-init.c +++ b/elf/dl-init.c @@ -1,5 +1,5 @@ /* Return the next shared object initializer function not yet run. -Copyright (C) 1995 Free Software Foundation, Inc. +Copyright (C) 1995, 1996 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -21,45 +21,35 @@ Cambridge, MA 02139, USA. */ #include <link.h> +/* Run initializers for MAP and its dependencies, in inverse dependency + order (that is, leaf nodes first). */ + Elf32_Addr -_dl_init_next (void) +_dl_init_next (struct link_map *map) { - struct link_map *l; - Elf32_Addr init; + unsigned int i; + + /* The search list for symbol lookup is a flat list in top-down + dependency order, so processing that list from back to front gets us + breadth-first leaf-to-root order. */ - Elf32_Addr next_init (struct link_map *l) + i = map->l_nsearchlist; + while (i-- > 0) { + struct link_map *l = map->l_searchlist[i]; + if (l->l_init_called) /* This object is all done. */ - return 0; + continue; + if (l->l_init_running) { /* This object's initializer was just running. Now mark it as having run, so this object will be skipped in the future. */ - l->l_init_called = 1; l->l_init_running = 0; - return 0; - } - - if (l->l_info[DT_NEEDED]) - { - /* Find each dependency in order, and see if it - needs to run an initializer. */ - const char *strtab - = ((void *) l->l_addr + l->l_info[DT_STRTAB]->d_un.d_ptr); - const Elf32_Dyn *d; - for (d = l->l_ld; d->d_tag != DT_NULL; ++d) - if (d->d_tag == DT_NEEDED) - { - struct link_map *needed - = _dl_map_object (l, strtab + d->d_un.d_val); - Elf32_Addr init; - --needed->l_opencount; - init = next_init (needed); /* Recurse on this dependency. */ - if (init != 0) - return init; - } + l->l_init_called = 1; + continue; } if (l->l_info[DT_INIT] && @@ -73,17 +63,7 @@ _dl_init_next (void) /* No initializer for this object. Mark it so we will skip it in the future. */ l->l_init_called = 1; - return 0; - } - - /* Look for the first initializer not yet called. */ - l = _dl_loaded; - do - { - init = next_init (l); - l = l->l_next; } - while (init == 0 && l); - return init; + return 0; } diff --git a/elf/dladdr.c b/elf/dladdr.c index 166952ac46..87283e2586 100644 --- a/elf/dladdr.c +++ b/elf/dladdr.c @@ -20,7 +20,6 @@ Cambridge, MA 02139, USA. */ #include <stddef.h> #include <link.h> #include <dlfcn.h> -#include <setjmp.h> int @@ -30,7 +29,6 @@ dladdr (void *address, Dl_info *info) struct link_map *l, *match; const Elf32_Sym *symtab, *matchsym; const char *strtab; - Elf32_Word symidx; /* Find the highest-addressed object that ADDRESS is not below. */ match = NULL; diff --git a/elf/dlclose.c b/elf/dlclose.c index 06b2d1bdcd..fbb3ca6fe2 100644 --- a/elf/dlclose.c +++ b/elf/dlclose.c @@ -1,5 +1,5 @@ /* dlclose -- Close a handle opened by `dlopen'. -Copyright (C) 1995 Free Software Foundation, Inc. +Copyright (C) 1995, 1996 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -32,64 +32,68 @@ dlclose (void *handle) void doit (void) { struct link_map *map = handle; + struct link_map **list; + unsigned int i; if (map->l_opencount == 0) LOSE ("shared object not open"); /* Decrement the reference count. */ - --map->l_opencount; - - if (map->l_opencount == 0 && map->l_type == lt_loaded) + if (--map->l_opencount > 0 || map->l_type != lt_loaded) + /* There are still references to this object. Do nothing more. */ + return; + + list = map->l_searchlist; + + /* The search list contains a counted reference to each object it + points to, the 0th elt being MAP itself. Decrement the reference + counts on all the objects MAP depends on. */ + for (i = 1; i < map->l_nsearchlist; ++i) + --list[i]->l_opencount; + + /* Clear the search list so it doesn't get freed while we are still + using it. We have cached it in LIST and will free it when + finished. */ + map->l_searchlist = NULL; + + /* Check each element of the search list to see if all references to + it are gone. */ + for (i = 0; i < map->l_nsearchlist; ++i) { - /* That was the last reference, and this was a dlopen-loaded - object. We can unmap it. */ - const Elf32_Phdr *ph; - - if (map->l_info[DT_FINI]) - /* Call its termination function. */ - (*(void (*) (void)) ((void *) map->l_addr + - map->l_info[DT_FINI]->d_un.d_ptr)) (); - - if (map->l_info[DT_NEEDED]) + struct link_map *map = list[i]; + if (map->l_opencount == 0 && map->l_type == lt_loaded) { - /* Also close all the dependencies. */ - const char *strtab - = (void *) map->l_addr + map->l_info[DT_STRTAB]->d_un.d_ptr; - const Elf32_Dyn *d; - for (d = map->l_ld; d->d_tag != DT_NULL; ++d) - if (d->d_tag == DT_NEEDED) + /* That was the last reference, and this was a dlopen-loaded + object. We can unmap it. */ + const Elf32_Phdr *ph; + + if (map->l_info[DT_FINI]) + /* Call its termination function. */ + (*(void (*) (void)) ((void *) map->l_addr + + map->l_info[DT_FINI]->d_un.d_ptr)) (); + + /* Unmap the segments. */ + for (ph = map->l_phdr; ph < &map->l_phdr[map->l_phnum]; ++ph) + if (ph->p_type == PT_LOAD) { - /* It must already be open, since this one needed it; - so dlopen will just find us its `struct link_map' - and bump its reference count. */ - struct link_map *o, *dep - = dlopen (strtab + d->d_un.d_val, RTLD_LAZY); - --dep->l_opencount; /* Lose the ref from that dlopen. */ - /* Now we have the handle; we can close it for real. */ - o = map; - map = dep; - doit (); - map = o; + Elf32_Addr mapstart = ph->p_vaddr & ~(ph->p_align - 1); + Elf32_Addr mapend = ((ph->p_vaddr + ph->p_memsz + + ph->p_align - 1) + & ~(ph->p_align - 1)); + munmap ((caddr_t) mapstart, mapend - mapstart); } - } - /* Unmap the segments. */ - for (ph = map->l_phdr; ph < &map->l_phdr[map->l_phnum]; ++ph) - if (ph->p_type == PT_LOAD) - { - Elf32_Addr mapstart = ph->p_vaddr & ~(ph->p_align - 1); - Elf32_Addr mapend = ((ph->p_vaddr + ph->p_memsz - + ph->p_align - 1) - & ~(ph->p_align - 1)); - munmap ((caddr_t) mapstart, mapend - mapstart); - } - - /* Finally, unlink the data structure and free it. */ - map->l_prev->l_next = map->l_next; - if (map->l_next) - map->l_next->l_prev = map->l_prev; - free (map); + /* Finally, unlink the data structure and free it. */ + map->l_prev->l_next = map->l_next; + if (map->l_next) + map->l_next->l_prev = map->l_prev; + if (map->l_searchlist) + free (map->l_searchlist); + free (map); + } } + + free (list); } return _dlerror_run (doit) ? -1 : 0; diff --git a/elf/dlsym.c b/elf/dlsym.c index 804d404bb3..f874af780a 100644 --- a/elf/dlsym.c +++ b/elf/dlsym.c @@ -27,21 +27,13 @@ void * dlsym (void *handle, const char *name) { struct link_map *map = handle; - struct link_map *real_next; Elf32_Addr loadbase; const Elf32_Sym *ref = NULL; - int lose; void doit (void) { struct link_map *scope[2] = { map, NULL }; loadbase = _dl_lookup_symbol (name, &ref, scope, map->l_name, 0, 0); } - /* Confine the symbol scope to just this map. */ - real_next = map->l_next; - map->l_next = NULL; - lose = _dlerror_run (doit); - map->l_next = real_next; - - return lose ? NULL : (void *) (loadbase + ref->st_value); + return _dlerror_run (doit) ? NULL : (void *) (loadbase + ref->st_value); } diff --git a/elf/link.h b/elf/link.h index 73782d8ac3..51740eeeee 100644 --- a/elf/link.h +++ b/elf/link.h @@ -111,6 +111,7 @@ struct link_map unsigned int l_relocated:1; /* Nonzero if object's relocations done. */ unsigned int l_init_called:1; /* Nonzero if DT_INIT function called. */ unsigned int l_init_running:1; /* Nonzero while DT_INIT function runs. */ + unsigned int l_reserved:3; /* Reserved for internal use. */ }; /* Internal functions of the run-time dynamic linker. @@ -231,10 +232,11 @@ extern struct link_map *_dl_new_object (char *realname, const char *libname, If LAZY is nonzero, don't relocate its PLT. */ extern void _dl_relocate_object (struct link_map *map, int lazy); -/* Return the address of the next initializer function not yet run. - When there are no more initializers to be run, this returns zero. - The functions are returned in the order they should be called. */ -extern Elf32_Addr _dl_init_next (void); +/* Return the address of the next initializer function for MAP or one of + its dependencies that has not yet been run. When there are no more + initializers to be run, this returns zero. The functions are returned + in the order they should be called. */ +extern Elf32_Addr _dl_init_next (struct link_map *map); /* Call the finalizer functions of all shared objects whose initializer functions have completed. */ |