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#include <assert.h>
#include <stdlib.h>
#include <libelfu/libelfu.h>
/* Meta-functions */
void* elfu_mScnForall(ElfuElf *me, SectionHandlerFunc f, void *aux1, void *aux2)
{
ElfuPhdr *mp;
ElfuScn *ms;
// TODO: Sort PHDRs by offset before interating
CIRCLEQ_FOREACH(mp, &me->phdrList, elem) {
if (mp->phdr.p_type != PT_LOAD) {
continue;
}
CIRCLEQ_FOREACH(ms, &mp->childScnList, elemChildScn) {
void *rv = f(me, ms, aux1, aux2);
if (rv) {
return rv;
}
}
}
CIRCLEQ_FOREACH(ms, &me->orphanScnList, elemChildScn) {
void *rv = f(me, ms, aux1, aux2);
if (rv) {
return rv;
}
}
return NULL;
}
/* Counting */
static void* subCounter(ElfuElf *me, ElfuScn *ms, void *aux1, void *aux2)
{
size_t *i = (size_t*)aux1;
ElfuScn *otherScn = (ElfuScn*)aux2;
if (ms == otherScn) {
return ms;
}
*i += 1;
/* Continue */
return NULL;
}
size_t elfu_mScnCount(ElfuElf *me)
{
/* NULL section *is not* counted */
size_t i = 0;
assert(me);
elfu_mScnForall(me, subCounter, &i, NULL);
return i;
}
/* Returns the index a section would have in the flattened ELF */
size_t elfu_mScnIndex(ElfuElf *me, ElfuScn *ms)
{
/* NULL section *is* counted */
size_t i = 1;
assert(me);
assert(ms);
elfu_mScnForall(me, subCounter, &i, ms);
/* If this assertion is broken then ms is not a section in me. */
assert(i <= elfu_mScnCount(me));
return i;
}
static void* subOldscn(ElfuElf *me, ElfuScn *ms, void *aux1, void *aux2)
{
ElfuScn *otherScn = (ElfuScn*)aux1;
(void)aux2;
if (ms->oldptr == otherScn) {
return ms;
}
/* Continue */
return NULL;
}
/* Returns the section with oldscn == oldscn */
ElfuScn* elfu_mScnByOldscn(ElfuElf *me, ElfuScn *oldscn)
{
assert(me);
assert(oldscn);
return elfu_mScnForall(me, subOldscn, oldscn, NULL);
}
/* Convenience */
char* elfu_mScnName(ElfuElf *me, ElfuScn *ms)
{
assert(me);
assert(ms);
if (!me->shstrtab) {
return NULL;
}
if (!me->shstrtab->data.d_buf) {
return NULL;
}
return &((char*)me->shstrtab->data.d_buf)[ms->shdr.sh_name];
}
static void* subScnsToArray(ElfuElf *me, ElfuScn *ms, void *aux1, void *aux2)
{
ElfuScn **arr = (ElfuScn**)aux1;
size_t *i = (size_t*)aux2;
arr[(*i)] = ms;
*i += 1;
/* Continue */
return NULL;
}
static int cmpScnOffs(const void *ms1, const void *ms2)
{
ElfuScn *s1;
ElfuScn *s2;
assert(ms1);
assert(ms2);
s1 = *(ElfuScn**)ms1;
s2 = *(ElfuScn**)ms2;
assert(s1);
assert(s2);
if (s1->shdr.sh_offset < s2->shdr.sh_offset) {
return -1;
} else if (s1->shdr.sh_offset == s2->shdr.sh_offset) {
return 0;
} else /* if (s1->shdr.sh_offset > s2->shdr.sh_offset) */ {
return 1;
}
}
ElfuScn** elfu_mScnSortedByOffset(ElfuElf *me, size_t *count)
{
size_t numSecs;
ElfuScn **sortedSecs;
size_t i;
assert(me);
/* Sort sections by offset in file */
numSecs = elfu_mScnCount(me);
sortedSecs = malloc(numSecs * sizeof(*sortedSecs));
if (!sortedSecs) {
ELFU_WARN("elfu_mScnSortedByOffset: Failed to allocate memory.\n");
return NULL;
}
i = 0;
elfu_mScnForall(me, subScnsToArray, sortedSecs, &i);
assert(i == numSecs);
qsort(sortedSecs, numSecs, sizeof(*sortedSecs), cmpScnOffs);
*count = numSecs;
return sortedSecs;
}
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