musl/arch/powerpc/reloc.h
Rich Felker a4db94ab78 dynamic linking support for powerpc
incomplete but at least partly working. requires all files to be
compiled in the new "secure" plt model, not the old one that put plt
code in the data segment. TLS is untested but may work. invoking the
dynamic linker explicitly to load a program does not yet handle argv
correctly.
2012-11-16 22:22:34 -05:00

56 lines
1.4 KiB
C

#include <string.h>
#include <elf.h>
#define ETC_LDSO_PATH "/etc/ld-musl-powerpc.path"
#define IS_COPY(x) ((x)==R_PPC_COPY)
#define IS_PLT(x) ((x)==R_PPC_JMP_SLOT)
// see linux' arch/powerpc/include/asm/elf.h
static inline void do_single_reloc(
struct dso *self, unsigned char *base_addr,
size_t *reloc_addr, int type, size_t addend,
Sym *sym, size_t sym_size,
struct symdef def, size_t sym_val)
{
switch(type) {
case R_PPC_GLOB_DAT:
case R_PPC_JMP_SLOT:
case R_PPC_ADDR32:
*reloc_addr = sym_val + addend;
break;
case R_PPC_COPY:
memcpy(reloc_addr, (void *)sym_val, sym_size);
break;
case R_PPC_RELATIVE:
*reloc_addr = (size_t)base_addr + addend;
break;
case R_PPC_DTPMOD32:
*reloc_addr = def.dso ? def.dso->tls_id : self->tls_id;
break;
case R_PPC_DTPREL32:
*reloc_addr = def.sym->st_value + addend;
break;
case R_PPC_TPREL32:
*reloc_addr += def.sym
? def.sym->st_value + def.dso->tls_offset - 0x7000
: self->tls_offset - 0x7000;
break;
}
}
void __reloc_self(int c, size_t *a, size_t *dynv)
{
char *base;
size_t t[20], n;
for (a+=c+1; *a; a++);
for (a++; *a; a+=2) if (*a<20) t[*a] = a[1];
base = (char *)t[AT_BASE];
if (!base) base = (char *)(t[AT_PHDR] & -4096);
for (a=dynv; *a; a+=2) if (*a<20) t[*a] = a[1];
n = t[DT_RELASZ];
for (a=(void *)(base+t[DT_RELA]); n; a+=3, n-=12)
if (a[1]%256 == R_PPC_RELATIVE)
*(size_t *)(base+a[0]) = (size_t)base + a[2];
}