diff options
Diffstat (limited to 'libelf/elf_end.c')
| -rw-r--r-- | libelf/elf_end.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/libelf/elf_end.c b/libelf/elf_end.c new file mode 100644 index 00000000..086ff633 --- /dev/null +++ b/libelf/elf_end.c @@ -0,0 +1,201 @@ +/* Free resources associated with Elf descriptor. + Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004 Red Hat, Inc. + Written by Ulrich Drepper <drepper@redhat.com>, 1998. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, version 2. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include <assert.h> +#include <stddef.h> +#include <stdlib.h> +#include <sys/mman.h> + +#include "libelfP.h" + + +int +elf_end (elf) + Elf *elf; +{ + Elf *parent; + + if (elf == NULL) + /* This is allowed and is a no-op. */ + return 0; + + /* Make sure we are alone. */ + rwlock_wrlock (elf->lock); + + if (elf->ref_count != 0 && --elf->ref_count != 0) + { + /* Not yet the last activation. */ + int result = elf->ref_count; + rwlock_unlock (elf->lock); + return result; + } + + if (elf->kind == ELF_K_AR) + { + /* We cannot remove the descriptor now since we still have some + descriptors which depend on it. But we can free the archive + symbol table since this is only available via the archive ELF + descriptor. The long name table cannot be freed yet since + the archive headers for the ELF files in the archive point + into this array. */ + free (elf->state.ar.ar_sym); + elf->state.ar.ar_sym = NULL; + + if (elf->state.ar.children != NULL) + return 0; + } + + /* Remove this structure from the children list. */ + parent = elf->parent; + if (parent != NULL) + { + /* This is tricky. Lock must be acquire from the father to + the child but here we already have the child lock. We + solve this problem by giving free the child lock. The + state of REF_COUNT==0 is handled all over the library, so + this should be ok. */ + rwlock_unlock (elf->lock); + rwlock_rdlock (parent->lock); + rwlock_wrlock (elf->lock); + + if (parent->state.ar.children == elf) + parent->state.ar.children = elf->next; + else + { + struct Elf *child = parent->state.ar.children; + + while (child->next != elf) + child = child->next; + + child->next = elf->next; + } + + rwlock_unlock (parent->lock); + } + + /* This was the last activation. Free all resources. */ + switch (elf->kind) + { + case ELF_K_AR: + if (elf->state.ar.long_names != NULL) + free (elf->state.ar.long_names); + break; + + case ELF_K_ELF: + { + Elf_ScnList *list = (elf->class == ELFCLASS32 + || (offsetof (struct Elf, state.elf32.scns) + == offsetof (struct Elf, state.elf64.scns)) + ? &elf->state.elf32.scns + : &elf->state.elf64.scns); + + do + { + /* Free all separately allocated section headers. */ + size_t cnt = list->max; + + while (cnt-- > 0) + { + /* These pointers can be NULL; it's safe to use + 'free' since it will check for this. */ + Elf_Scn *scn = &list->data[cnt]; + Elf_Data_List *runp; + + if ((scn->shdr_flags & ELF_F_MALLOCED) != 0) + /* It doesn't matter which pointer. */ + free (scn->shdr.e32); + + /* If the file has the same byte order and the + architecture doesn't require overly stringent + alignment the raw data buffer is the same as the + one used for presenting to the caller. */ + if (scn->data_base != scn->rawdata_base) + free (scn->data_base); + + /* The section data is allocated if we couldn't mmap + the file. */ + if (elf->map_address == NULL) + free (scn->rawdata_base); + + /* Free the list of data buffers for the section. + We don't free the buffers themselves since this + is the users job. */ + runp = scn->data_list.next; + while (runp != NULL) + { + Elf_Data_List *oldp = runp; + runp = runp->next; + if ((oldp->flags & ELF_F_MALLOCED) != 0) + free (oldp); + } + } + + /* Free the memory for the array. */ + Elf_ScnList *oldp = list; + list = list->next; + assert (list == NULL || oldp->cnt == oldp->max); + if (oldp != (elf->class == ELFCLASS32 + || (offsetof (struct Elf, state.elf32.scns) + == offsetof (struct Elf, state.elf64.scns)) + ? &elf->state.elf32.scns + : &elf->state.elf64.scns)) + free (oldp); + } + while (list != NULL); + } + + /* Free the section header. */ + if (elf->state.elf.shdr_malloced != 0) + free (elf->class == ELFCLASS32 + || (offsetof (struct Elf, state.elf32.shdr) + == offsetof (struct Elf, state.elf64.shdr)) + ? (void *) elf->state.elf32.shdr + : (void *) elf->state.elf64.shdr); + + /* Free the program header. */ + if ((elf->state.elf.phdr_flags & ELF_F_MALLOCED) != 0) + free (elf->class == ELFCLASS32 + || (offsetof (struct Elf, state.elf32.phdr) + == offsetof (struct Elf, state.elf64.phdr)) + ? (void *) elf->state.elf32.phdr + : (void *) elf->state.elf64.phdr); + break; + + default: + break; + } + + if (elf->map_address != NULL && parent == NULL) + { + /* The file was read or mapped for this descriptor. */ + if ((elf->flags & ELF_F_MALLOCED) != 0) + free (elf->map_address); + else if ((elf->flags & ELF_F_MMAPPED) != 0) + munmap (elf->map_address, elf->maximum_size); + } + + rwlock_fini (elf->lock); + + /* Finally the descriptor itself. */ + free (elf); + + return parent != NULL && parent->ref_count == 0 ? elf_end (parent) : 0; +} |