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#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <libelfu/libelfu.h>
static void flattenSymtab(ElfuElf *me)
{
ElfuSym *sym;
size_t numsyms = 0;
elfu_mLayoutAuto(me);
/* Update section indexes and count symbols */
CIRCLEQ_FOREACH(sym, &me->symtab->symtab.syms, elem) {
if (sym->scnptr) {
sym->shndx = elfu_mScnIndex(me, sym->scnptr);
}
numsyms++;
}
/* Copy symbols to elfclass-specific format */
if (me->elfclass == ELFCLASS32) {
size_t newsize = (numsyms + 1) * sizeof(Elf32_Sym);
size_t i;
if (me->symtab->data.d_buf) {
free(me->symtab->data.d_buf);
}
me->symtab->data.d_buf = malloc(newsize);
assert(me->symtab->data.d_buf);
me->symtab->data.d_size = newsize;
me->symtab->shdr.sh_size = newsize;
memset(me->symtab->data.d_buf, 0, newsize);
i = 1;
CIRCLEQ_FOREACH(sym, &me->symtab->symtab.syms, elem) {
Elf32_Sym *es = ((Elf32_Sym*)me->symtab->data.d_buf) + i;
es->st_name = sym->name;
es->st_value = sym->value;
es->st_size = sym->size;
es->st_info = ELF32_ST_INFO(sym->bind, sym->type);
es->st_other = sym->other;
es->st_shndx = sym->shndx;
i++;
}
} else if (me->elfclass == ELFCLASS64) {
size_t newsize = (numsyms + 1) * sizeof(Elf64_Sym);
size_t i;
if (me->symtab->data.d_buf) {
free(me->symtab->data.d_buf);
}
me->symtab->data.d_buf = malloc(newsize);
assert(me->symtab->data.d_buf);
me->symtab->data.d_size = newsize;
me->symtab->shdr.sh_size = newsize;
memset(me->symtab->data.d_buf, 0, newsize);
i = 1;
CIRCLEQ_FOREACH(sym, &me->symtab->symtab.syms, elem) {
Elf64_Sym *es = ((Elf64_Sym*)me->symtab->data.d_buf) + i;
es->st_name = sym->name;
es->st_value = sym->value;
es->st_size = sym->size;
es->st_info = ELF64_ST_INFO(sym->bind, sym->type);
es->st_other = sym->other;
es->st_shndx = sym->shndx;
i++;
}
} else {
// Unknown elfclass
assert(0);
}
elfu_mLayoutAuto(me);
}
static void modelToPhdrs(ElfuElf *me, Elf *e)
{
ElfuPhdr *mp;
size_t i;
/* Count PHDRs */
i = 0;
CIRCLEQ_FOREACH(mp, &me->phdrList, elem) {
i++;
}
if (!gelf_newphdr(e, i)) {
ELFU_WARNELF("gelf_newphdr");
}
/* Copy PHDRs */
i = 0;
CIRCLEQ_FOREACH(mp, &me->phdrList, elem) {
if (!gelf_update_phdr (e, i, &mp->phdr)) {
ELFU_WARNELF("gelf_update_phdr");
}
i++;
}
}
static void* modelToSection(ElfuElf *me, ElfuScn *ms, void *aux1, void *aux2)
{
(void) me;
(void) aux2;
Elf *e = (Elf*)aux1;
Elf_Scn *scnOut;
scnOut = elf_newscn(e);
if (!scnOut) {
ELFU_WARNELF("elf_newscn");
return (void*)-1;
}
/* SHDR */
if (ms->linkptr) {
ms->shdr.sh_link = elfu_mScnIndex(me, ms->linkptr);
}
if (ms->infoptr) {
ms->shdr.sh_info = elfu_mScnIndex(me, ms->infoptr);
}
if (!gelf_update_shdr(scnOut, &ms->shdr)) {
ELFU_WARNELF("gelf_update_shdr");
}
/* Data */
if (ms->data.d_buf) {
Elf_Data *dataOut = elf_newdata(scnOut);
if (!dataOut) {
ELFU_WARNELF("elf_newdata");
}
dataOut->d_align = ms->data.d_align;
dataOut->d_buf = ms->data.d_buf;
dataOut->d_off = ms->data.d_off;
dataOut->d_type = ms->data.d_type;
dataOut->d_size = ms->data.d_size;
dataOut->d_version = ms->data.d_version;
}
return NULL;
}
void elfu_mToElf(ElfuElf *me, Elf *e)
{
if (me->symtab) {
flattenSymtab(me);
}
/* We control the ELF file's layout now. */
/* tired's libelf also offers ELF_F_LAYOUT_OVERLAP for overlapping sections,
* but we don't want that since we filtered it out in the reading stage
* already. It would be too mind-blowing to handle the dependencies between
* the PHDRs and sections then... */
elf_flagelf(e, ELF_C_SET, ELF_F_LAYOUT);
/* EHDR */
if (!gelf_newehdr(e, me->elfclass)) {
ELFU_WARNELF("gelf_newehdr");
}
if (me->shstrtab) {
me->ehdr.e_shstrndx = elfu_mScnIndex(me, me->shstrtab);
}
if (!gelf_update_ehdr(e, &me->ehdr)) {
ELFU_WARNELF("gelf_update_ehdr");
}
/* Sections */
elfu_mScnForall(me, modelToSection, e, NULL);
/* PHDRs */
modelToPhdrs(me, e);
elf_flagelf(e, ELF_C_SET, ELF_F_DIRTY);
}
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