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/common.h b/libelf/common.h
new file mode 100644
index 0000000..744f1bb
--- /dev/null
+++ b/libelf/common.h
@@ -0,0 +1,163 @@
+/* Common definitions for handling files in memory or only on disk.
+ Copyright (C) 1998, 1999, 2000, 2002, 2005, 2008 Red Hat, Inc.
+ This file is part of elfutils.
+ Written by Ulrich Drepper <drepper@redhat.com>, 1998.
+
+ 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/>. */
+
+#ifndef _COMMON_H
+#define _COMMON_H 1
+
+#include <ar.h>
+#include <byteswap.h>
+#include <endian.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "libelfP.h"
+
+static inline Elf_Kind
+__attribute__ ((unused))
+determine_kind (void *buf, size_t len)
+{
+ /* First test for an archive. */
+ if (len >= SARMAG && memcmp (buf, ARMAG, SARMAG) == 0)
+ return ELF_K_AR;
+
+ /* Next try ELF files. */
+ if (len >= EI_NIDENT && memcmp (buf, ELFMAG, SELFMAG) == 0)
+ {
+ /* Could be an ELF file. */
+ int eclass = (int) ((unsigned char *) buf)[EI_CLASS];
+ int data = (int) ((unsigned char *) buf)[EI_DATA];
+ int version = (int) ((unsigned char *) buf)[EI_VERSION];
+
+ if (eclass > ELFCLASSNONE && eclass < ELFCLASSNUM
+ && data > ELFDATANONE && data < ELFDATANUM
+ && version > EV_NONE && version < EV_NUM)
+ return ELF_K_ELF;
+ }
+
+ /* We do not know this file type. */
+ return ELF_K_NONE;
+}
+
+
+/* Allocate an Elf descriptor and fill in the generic information. */
+static inline Elf *
+__attribute__ ((unused))
+allocate_elf (int fildes, void *map_address, off_t offset, size_t maxsize,
+ Elf_Cmd cmd, Elf *parent, Elf_Kind kind, size_t extra)
+{
+ Elf *result = (Elf *) calloc (1, sizeof (Elf) + extra);
+ if (result == NULL)
+ __libelf_seterrno (ELF_E_NOMEM);
+ else
+ {
+ result->kind = kind;
+ result->ref_count = 1;
+ result->cmd = cmd;
+ result->fildes = fildes;
+ result->start_offset = offset;
+ result->maximum_size = maxsize;
+ result->map_address = map_address;
+ result->parent = parent;
+
+ rwlock_init (result->lock);
+ }
+
+ return result;
+}
+
+
+/* Acquire lock for the descriptor and all children. */
+static void
+__attribute__ ((unused))
+libelf_acquire_all (Elf *elf)
+{
+ rwlock_wrlock (elf->lock);
+
+ if (elf->kind == ELF_K_AR)
+ {
+ Elf *child = elf->state.ar.children;
+
+ while (child != NULL)
+ {
+ if (child->ref_count != 0)
+ libelf_acquire_all (child);
+ child = child->next;
+ }
+ }
+}
+
+/* Release own lock and those of the children. */
+static void
+__attribute__ ((unused))
+libelf_release_all (Elf *elf)
+{
+ if (elf->kind == ELF_K_AR)
+ {
+ Elf *child = elf->state.ar.children;
+
+ while (child != NULL)
+ {
+ if (child->ref_count != 0)
+ libelf_release_all (child);
+ child = child->next;
+ }
+ }
+
+ rwlock_unlock (elf->lock);
+}
+
+
+/* Macro to convert endianess in place. It determines the function it
+ has to use itself. */
+#define CONVERT(Var) \
+ (Var) = (sizeof (Var) == 1 \
+ ? (unsigned char) (Var) \
+ : (sizeof (Var) == 2 \
+ ? bswap_16 (Var) \
+ : (sizeof (Var) == 4 \
+ ? bswap_32 (Var) \
+ : bswap_64 (Var))))
+
+#define CONVERT_TO(Dst, Var) \
+ (Dst) = (sizeof (Var) == 1 \
+ ? (unsigned char) (Var) \
+ : (sizeof (Var) == 2 \
+ ? bswap_16 (Var) \
+ : (sizeof (Var) == 4 \
+ ? bswap_32 (Var) \
+ : bswap_64 (Var))))
+
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+# define MY_ELFDATA ELFDATA2LSB
+#else
+# define MY_ELFDATA ELFDATA2MSB
+#endif
+
+#endif /* common.h */