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Diffstat (limited to 'REORG.TODO/elf/dl-object.c')
| -rw-r--r-- | REORG.TODO/elf/dl-object.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/REORG.TODO/elf/dl-object.c b/REORG.TODO/elf/dl-object.c new file mode 100644 index 0000000000..4c43235148 --- /dev/null +++ b/REORG.TODO/elf/dl-object.c @@ -0,0 +1,229 @@ +/* Storage management for the chain of loaded shared objects. + Copyright (C) 1995-2017 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <errno.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include <ldsodefs.h> + +#include <assert.h> + + +/* Add the new link_map NEW to the end of the namespace list. */ +void +internal_function +_dl_add_to_namespace_list (struct link_map *new, Lmid_t nsid) +{ + /* We modify the list of loaded objects. */ + __rtld_lock_lock_recursive (GL(dl_load_write_lock)); + + if (GL(dl_ns)[nsid]._ns_loaded != NULL) + { + struct link_map *l = GL(dl_ns)[nsid]._ns_loaded; + while (l->l_next != NULL) + l = l->l_next; + new->l_prev = l; + /* new->l_next = NULL; Would be necessary but we use calloc. */ + l->l_next = new; + } + else + GL(dl_ns)[nsid]._ns_loaded = new; + ++GL(dl_ns)[nsid]._ns_nloaded; + new->l_serial = GL(dl_load_adds); + ++GL(dl_load_adds); + + __rtld_lock_unlock_recursive (GL(dl_load_write_lock)); +} + + +/* Allocate a `struct link_map' for a new object being loaded, + and enter it into the _dl_loaded list. */ +struct link_map * +internal_function +_dl_new_object (char *realname, const char *libname, int type, + struct link_map *loader, int mode, Lmid_t nsid) +{ + size_t libname_len = strlen (libname) + 1; + struct link_map *new; + struct libname_list *newname; +#ifdef SHARED + /* We create the map for the executable before we know whether we have + auditing libraries and if yes, how many. Assume the worst. */ + unsigned int naudit = GLRO(dl_naudit) ?: ((mode & __RTLD_OPENEXEC) + ? DL_NNS : 0); + size_t audit_space = naudit * sizeof (new->l_audit[0]); +#else +# define audit_space 0 +#endif + + new = (struct link_map *) calloc (sizeof (*new) + audit_space + + sizeof (struct link_map *) + + sizeof (*newname) + libname_len, 1); + if (new == NULL) + return NULL; + + new->l_real = new; + new->l_symbolic_searchlist.r_list = (struct link_map **) ((char *) (new + 1) + + audit_space); + + new->l_libname = newname + = (struct libname_list *) (new->l_symbolic_searchlist.r_list + 1); + newname->name = (char *) memcpy (newname + 1, libname, libname_len); + /* newname->next = NULL; We use calloc therefore not necessary. */ + newname->dont_free = 1; + + /* When we create the executable link map, or a VDSO link map, we start + with "" for the l_name. In these cases "" points to ld.so rodata + and won't get dumped during core file generation. Therefore to assist + gdb and to create more self-contained core files we adjust l_name to + point at the newly allocated copy (which will get dumped) instead of + the ld.so rodata copy. */ + new->l_name = *realname ? realname : (char *) newname->name + libname_len - 1; + new->l_type = type; + /* If we set the bit now since we know it is never used we avoid + dirtying the cache line later. */ + if ((GLRO(dl_debug_mask) & DL_DEBUG_UNUSED) == 0) + new->l_used = 1; + new->l_loader = loader; +#if NO_TLS_OFFSET != 0 + new->l_tls_offset = NO_TLS_OFFSET; +#endif + new->l_ns = nsid; + +#ifdef SHARED + for (unsigned int cnt = 0; cnt < naudit; ++cnt) + { + new->l_audit[cnt].cookie = (uintptr_t) new; + /* new->l_audit[cnt].bindflags = 0; */ + } +#endif + + /* new->l_global = 0; We use calloc therefore not necessary. */ + + /* Use the 'l_scope_mem' array by default for the 'l_scope' + information. If we need more entries we will allocate a large + array dynamically. */ + new->l_scope = new->l_scope_mem; + new->l_scope_max = sizeof (new->l_scope_mem) / sizeof (new->l_scope_mem[0]); + + /* Counter for the scopes we have to handle. */ + int idx = 0; + + if (GL(dl_ns)[nsid]._ns_loaded != NULL) + /* Add the global scope. */ + new->l_scope[idx++] = &GL(dl_ns)[nsid]._ns_loaded->l_searchlist; + + /* If we have no loader the new object acts as it. */ + if (loader == NULL) + loader = new; + else + /* Determine the local scope. */ + while (loader->l_loader != NULL) + loader = loader->l_loader; + + /* Insert the scope if it isn't the global scope we already added. */ + if (idx == 0 || &loader->l_searchlist != new->l_scope[0]) + { + if ((mode & RTLD_DEEPBIND) != 0 && idx != 0) + { + new->l_scope[1] = new->l_scope[0]; + idx = 0; + } + + new->l_scope[idx] = &loader->l_searchlist; + } + + new->l_local_scope[0] = &new->l_searchlist; + + /* Don't try to find the origin for the main map which has the name "". */ + if (realname[0] != '\0') + { + size_t realname_len = strlen (realname) + 1; + char *origin; + char *cp; + + if (realname[0] == '/') + { + /* It is an absolute path. Use it. But we have to make a + copy since we strip out the trailing slash. */ + cp = origin = (char *) malloc (realname_len); + if (origin == NULL) + { + origin = (char *) -1; + goto out; + } + } + else + { + size_t len = realname_len; + char *result = NULL; + + /* Get the current directory name. */ + origin = NULL; + do + { + char *new_origin; + + len += 128; + new_origin = (char *) realloc (origin, len); + if (new_origin == NULL) + /* We exit the loop. Note that result == NULL. */ + break; + origin = new_origin; + } + while ((result = __getcwd (origin, len - realname_len)) == NULL + && errno == ERANGE); + + if (result == NULL) + { + /* We were not able to determine the current directory. + Note that free(origin) is OK if origin == NULL. */ + free (origin); + origin = (char *) -1; + goto out; + } + + /* Find the end of the path and see whether we have to add a + slash. We could use rawmemchr but this need not be + fast. */ + cp = (strchr) (origin, '\0'); + if (cp[-1] != '/') + *cp++ = '/'; + } + + /* Add the real file name. */ + cp = __mempcpy (cp, realname, realname_len); + + /* Now remove the filename and the slash. Leave the slash if + the name is something like "/foo". */ + do + --cp; + while (*cp != '/'); + + if (cp == origin) + /* Keep the only slash which is the first character. */ + ++cp; + *cp = '\0'; + + out: + new->l_origin = origin; + } + + return new; +} |