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/* Create new section in output file.
Copyright (C) 2002 Red Hat, Inc.
Written by Ulrich Drepper <drepper@redhat.com>, 2002.
This program is Open Source software; you can redistribute it and/or
modify it under the terms of the Open Software License version 1.0 as
published by the Open Source Initiative.
You should have received a copy of the Open Software License along
with this program; if not, you may obtain a copy of the Open Software
License version 1.0 from http://www.opensource.org/licenses/osl.php or
by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
3001 King Ranch Road, Ukiah, CA 95482. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <assert.h>
#include <error.h>
#include <libintl.h>
#include <stdlib.h>
#include <string.h>
#include <libasmP.h>
#include <libelf.h>
#include <system.h>
/* Memory for the default pattern. The type uses a flexible array
which does work well with a static initializer. So we play some
dirty tricks here. */
static const struct
{
struct FillPattern pattern;
char zero;
} xdefault_pattern =
{
.pattern =
{
.len = 1
},
.zero = '\0'
};
const struct FillPattern *__libasm_default_pattern = &xdefault_pattern.pattern;
static AsmScn_t *
text_newscn (AsmScn_t *result, GElf_Word type, GElf_Xword flags)
{
/* Buffer where we construct the flag string. */
char flagstr[sizeof (GElf_Xword) * 8 + 5];
char *wp = flagstr;
const char *typestr = "";
/* Only write out the flag string if this is the first time the
section is selected. Some assemblers cannot cope with the
.section pseudo-op otherwise. */
wp = stpcpy (wp, ", \"");
if (flags & SHF_WRITE)
*wp++ = 'w';
if (flags & SHF_ALLOC)
*wp++ = 'a';
if (flags & SHF_EXECINSTR)
*wp++ = 'x';
if (flags & SHF_MERGE)
*wp++ = 'M';
if (flags & SHF_STRINGS)
*wp++ = 'S';
if (flags & SHF_LINK_ORDER)
*wp++ = 'L';
*wp++ = '"';
if (type == SHT_PROGBITS)
typestr = ",@progbits";
else if (type == SHT_NOBITS)
typestr = ",@nobits";
/* Terminate the string. */
*wp = '\0';
printf ("\t.section \"%s\"%s%s\n", result->name, flagstr, typestr);
return result;
}
static AsmScn_t *
binary_newscn (AsmScn_t *result, GElf_Word type, GElf_Xword flags,
size_t scnname_len)
{
GElf_Shdr shdr_mem;
GElf_Shdr *shdr;
Elf_Scn *scn;
/* The initial subsection has the number zero. */
result->subsection_id = 0;
/* We start at offset zero. */
result->offset = 0;
/* And generic alignment. */
result->max_align = 1;
/* No output yet. */
result->content = NULL;
/* Put the default fill pattern in place. */
result->pattern = (struct FillPattern *) __libasm_default_pattern;
/* There are no subsections so far. */
result->subnext = NULL;
/* Add the name to the section header string table. */
result->data.main.strent = ebl_strtabadd (result->ctx->section_strtab,
result->name, scnname_len);
assert (result->data.main.strent != NULL);
/* Create the new ELF section. */
result->data.main.scn = scn = elf_newscn (result->ctx->out.elf);
if (scn == NULL)
{
free (result);
__libasm_seterrno (ASM_E_LIBELF);
return NULL;
}
/* Not part of a section group (yet). */
result->data.main.next_in_group = NULL;
/* Remember the flags. */
shdr = gelf_getshdr (scn, &shdr_mem);
shdr->sh_flags = flags;
result->type = shdr->sh_type = type;
(void) gelf_update_shdr (scn, shdr);
return result;
}
AsmScn_t *
asm_newscn (ctx, scnname, type, flags)
AsmCtx_t *ctx;
const char *scnname;
GElf_Word type;
GElf_Xword flags;
{
size_t scnname_len = strlen (scnname) + 1;
unsigned long int hval;
AsmScn_t *result;
/* If no context is given there might be an earlier error. */
if (ctx == NULL)
return NULL;
/* Check whether only flags are set which areselectable by the user. */
if (unlikely ((flags & ~(SHF_WRITE | SHF_ALLOC | SHF_EXECINSTR | SHF_MERGE
| SHF_STRINGS | SHF_LINK_ORDER)) != 0)
/* We allow only two section types: data and data without file
representation. */
|| (type != SHT_PROGBITS && unlikely (type != SHT_NOBITS)))
{
__libasm_seterrno (ASM_E_INVALID);
return NULL;
}
hval = elf_hash (scnname);
rwlock_wrlock (ctx->lock);
/* This is a new section. */
result = (AsmScn_t *) malloc (sizeof (AsmScn_t) + scnname_len);
if (result != NULL)
{
/* Add the name. */
memcpy (result->name, scnname, scnname_len);
/* Add the reference to the context. */
result->ctx = ctx;
/* Perform operations according to output mode. */
result = (unlikely (ctx->textp)
? text_newscn (result, type, flags)
: binary_newscn (result, type, flags, scnname_len));
/* If everything went well finally add the new section to the hash
table. */
if (result != NULL)
{
result->allnext = ctx->section_list;
ctx->section_list = result;
}
}
rwlock_unlock (ctx->lock);
return result;
}
INTDEF(asm_newscn)
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