MFP4: Add an implementation of the ELF(3) and GELF(3) API set.

Bump __FreeBSD_version.

Reviewed by:	jb

1 files changed, 156 insertions, 0 deletions

diff --git a/lib/libelf/elf_begin.c b/lib/libelf/elf_begin.c
new file mode 100644
index 0000000..d59042c
--- /dev/null
+++ b/lib/libelf/elf_begin.c
@@ -0,0 +1,156 @@
+/*-
+ * Copyright (c) 2006 Joseph Koshy
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/errno.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include <ar.h>
+#include <ctype.h>
+#include <libelf.h>
+
+#include "_libelf.h"
+
+static Elf *
+_libelf_open_object(int fd, Elf_Cmd c)
+{
+	Elf *e;
+	void *m;
+	struct stat sb;
+
+	/*
+	 * 'Raw' files are always mapped with 'PROT_READ'.  At
+	 * elf_update(3) time for files opened with ELF_C_RDWR the
+	 * mapping is unmapped, file data is written to using write(2)
+	 * and then the raw data is immediately mapped back in.
+	 */
+	if (fstat(fd, &sb) < 0) {
+		LIBELF_SET_ERROR(IO, errno);
+		return (NULL);
+	}
+
+	m = NULL;
+	if ((m = mmap(NULL, (size_t) sb.st_size, PROT_READ, MAP_PRIVATE, fd,
+	    (off_t) 0)) == MAP_FAILED) {
+		LIBELF_SET_ERROR(IO, errno);
+		return (NULL);
+	}
+
+	if ((e = elf_memory(m, (size_t) sb.st_size)) == NULL) {
+		(void) munmap(m, (size_t) sb.st_size);
+		return (NULL);
+	}
+
+	e->e_flags |= LIBELF_F_MMAP;
+	e->e_fd = fd;
+	e->e_cmd = c;
+
+	if (c == ELF_C_RDWR && e->e_kind == ELF_K_AR) {
+		(void) elf_end(e);
+		LIBELF_SET_ERROR(ARGUMENT, 0);
+		return (NULL);
+	}
+
+	return (e);
+}
+
+Elf *
+elf_begin(int fd, Elf_Cmd c, Elf *a)
+{
+	Elf *e;
+
+	e = NULL;
+
+	if (LIBELF_PRIVATE(version) == EV_NONE) {
+		LIBELF_SET_ERROR(SEQUENCE, 0);
+		return (NULL);
+	}
+
+	switch (c) {
+	case ELF_C_NULL:
+		return (NULL);
+
+	case ELF_C_WRITE:
+
+		if (a != NULL) { /* not allowed for ar(1) archives. */
+			LIBELF_SET_ERROR(ARGUMENT, 0);
+			return (NULL);
+		}
+
+		/*
+		 * Check writeability of `fd' immediately and fail if
+		 * not writeable.
+		 */
+		if (ftruncate(fd, (off_t) 0) < 0) {
+			LIBELF_SET_ERROR(IO, errno);
+			return (NULL);
+		}
+
+		if ((e = _libelf_allocate_elf()) != NULL) {
+			_libelf_init_elf(e, ELF_K_ELF);
+			e->e_byteorder = LIBELF_PRIVATE(byteorder);
+			e->e_fd = fd;
+			e->e_cmd = c;
+		}
+		return (e);
+
+	case ELF_C_RDWR:
+		if (a != NULL) { /* not allowed for ar(1) archives. */
+			LIBELF_SET_ERROR(ARGUMENT, 0);
+			return (NULL);
+		}
+		/*FALLTHROUGH*/
+	case ELF_C_READ:
+		/*
+		 * Descriptor `a' could be for a regular ELF file, or
+		 * for an ar(1) archive.
+		 */
+		if (a && (a->e_fd != fd || c != a->e_cmd)) {
+			LIBELF_SET_ERROR(ARGUMENT, 0);
+			return (NULL);
+		}
+
+		break;
+
+	default:
+		LIBELF_SET_ERROR(ARGUMENT, 0);
+		return (NULL);
+
+	}
+
+	if (a == NULL)
+		e = _libelf_open_object(fd, c);
+	else if (a->e_kind == ELF_K_AR)
+		e = _libelf_ar_open_member(fd, c, a);
+	else
+		(e = a)->e_activations++;
+
+	return (e);
+}