Squashed 'third_party/elfutils/' content from commit 555e15e
Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libelf/elf_getphdrnum.c b/libelf/elf_getphdrnum.c
new file mode 100644
index 0000000..f91cba9
--- /dev/null
+++ b/libelf/elf_getphdrnum.c
@@ -0,0 +1,142 @@
+/* Return number of program headers in the ELF file.
+ Copyright (C) 2010, 2014, 2015, 2016 Red Hat, Inc.
+ This file is part of elfutils.
+
+ This file is free software; you can redistribute it and/or modify
+ it under the terms of either
+
+ * the GNU Lesser General Public License as published by the Free
+ Software Foundation; either version 3 of the License, or (at
+ your option) any later version
+
+ or
+
+ * the GNU General Public License as published by the Free
+ Software Foundation; either version 2 of the License, or (at
+ your option) any later version
+
+ or both in parallel, as here.
+
+ elfutils 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 copies of the GNU General Public License and
+ the GNU Lesser General Public License along with this program. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <assert.h>
+#include <gelf.h>
+#include <stddef.h>
+
+#include "libelfP.h"
+
+
+int
+internal_function
+__elf_getphdrnum_rdlock (Elf *elf, size_t *dst)
+{
+ if (unlikely (elf->state.elf64.ehdr == NULL))
+ {
+ /* Maybe no ELF header was created yet. */
+ __libelf_seterrno (ELF_E_WRONG_ORDER_EHDR);
+ return -1;
+ }
+
+ *dst = (elf->class == ELFCLASS32
+ ? elf->state.elf32.ehdr->e_phnum
+ : elf->state.elf64.ehdr->e_phnum);
+
+ if (*dst == PN_XNUM)
+ {
+ const Elf_ScnList *const scns = (elf->class == ELFCLASS32
+ ? &elf->state.elf32.scns
+ : &elf->state.elf64.scns);
+
+ /* If there are no section headers, perhaps this is really just 65536
+ written without PN_XNUM support. Either that or it's bad data. */
+
+ if (elf->class == ELFCLASS32)
+ {
+ if (likely (scns->cnt > 0
+ && elf->state.elf32.scns.data[0].shdr.e32 != NULL))
+ *dst = scns->data[0].shdr.e32->sh_info;
+ }
+ else
+ {
+ if (likely (scns->cnt > 0
+ && elf->state.elf64.scns.data[0].shdr.e64 != NULL))
+ *dst = scns->data[0].shdr.e64->sh_info;
+ }
+ }
+
+ return 0;
+}
+
+int
+internal_function
+__elf_getphdrnum_chk_rdlock (Elf *elf, size_t *dst)
+{
+ int result = __elf_getphdrnum_rdlock (elf, dst);
+
+ /* If the phdrs haven't been created or read in yet then do some
+ sanity checking to make sure phnum and phoff are consistent. */
+ if (elf->state.elf.phdr == NULL)
+ {
+ Elf64_Off off = (elf->class == ELFCLASS32
+ ? elf->state.elf32.ehdr->e_phoff
+ : elf->state.elf64.ehdr->e_phoff);
+ if (unlikely (off == 0))
+ {
+ *dst = 0;
+ return result;
+ }
+
+ if (unlikely (off >= elf->maximum_size))
+ {
+ __libelf_seterrno (ELF_E_INVALID_DATA);
+ return -1;
+ }
+
+ /* Check for too many sections. */
+ size_t phdr_size = (elf->class == ELFCLASS32
+ ? sizeof (Elf32_Phdr) : sizeof (Elf64_Phdr));
+ if (unlikely (*dst > SIZE_MAX / phdr_size))
+ {
+ __libelf_seterrno (ELF_E_INVALID_DATA);
+ return -1;
+ }
+
+ /* Truncated file? Don't return more than can be indexed. */
+ if (unlikely (elf->maximum_size - off < *dst * phdr_size))
+ *dst = (elf->maximum_size - off) / phdr_size;
+ }
+
+ return result;
+}
+
+int
+elf_getphdrnum (Elf *elf, size_t *dst)
+{
+ int result;
+
+ if (elf == NULL)
+ return -1;
+
+ if (unlikely (elf->kind != ELF_K_ELF))
+ {
+ __libelf_seterrno (ELF_E_INVALID_HANDLE);
+ return -1;
+ }
+
+ rwlock_rdlock (elf->lock);
+ result = __elf_getphdrnum_chk_rdlock (elf, dst);
+ rwlock_unlock (elf->lock);
+
+ return result;
+}