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-rw-r--r--src/ldso/dlstart.c150
1 files changed, 0 insertions, 150 deletions
diff --git a/src/ldso/dlstart.c b/src/ldso/dlstart.c
deleted file mode 100644
index 46f50114..00000000
--- a/src/ldso/dlstart.c
+++ /dev/null
@@ -1,150 +0,0 @@
-#include <stddef.h>
-#include "dynlink.h"
-
-#ifdef SHARED
-
-#ifndef START
-#define START "_dlstart"
-#endif
-
-#include "crt_arch.h"
-
-#ifndef GETFUNCSYM
-#define GETFUNCSYM(fp, sym, got) do { \
-	__attribute__((__visibility__("hidden"))) void sym(); \
-	static void (*static_func_ptr)() = sym; \
-	__asm__ __volatile__ ( "" : "+m"(static_func_ptr) : : "memory"); \
-	*(fp) = static_func_ptr; } while(0)
-#endif
-
-__attribute__((__visibility__("hidden")))
-void _dlstart_c(size_t *sp, size_t *dynv)
-{
-	size_t i, aux[AUX_CNT], dyn[DYN_CNT];
-	size_t *rel, rel_size, base;
-
-	int argc = *sp;
-	char **argv = (void *)(sp+1);
-
-	for (i=argc+1; argv[i]; i++);
-	size_t *auxv = (void *)(argv+i+1);
-
-	for (i=0; i<AUX_CNT; i++) aux[i] = 0;
-	for (i=0; auxv[i]; i+=2) if (auxv[i]<AUX_CNT)
-		aux[auxv[i]] = auxv[i+1];
-
-#if DL_FDPIC
-	struct fdpic_loadseg *segs, fakeseg;
-	size_t j;
-	if (dynv) {
-		/* crt_arch.h entry point asm is responsible for reserving
-		 * space and moving the extra fdpic arguments to the stack
-		 * vector where they are easily accessible from C. */
-		segs = ((struct fdpic_loadmap *)(sp[-1] ? sp[-1] : sp[-2]))->segs;
-	} else {
-		/* If dynv is null, the entry point was started from loader
-		 * that is not fdpic-aware. We can assume normal fixed-
-		 * displacement ELF loading was performed, but when ldso was
-		 * run as a command, finding the Ehdr is a heursitic: we
-		 * have to assume Phdrs start in the first 4k of the file. */
-		base = aux[AT_BASE];
-		if (!base) base = aux[AT_PHDR] & -4096;
-		segs = &fakeseg;
-		segs[0].addr = base;
-		segs[0].p_vaddr = 0;
-		segs[0].p_memsz = -1;
-		Ehdr *eh = (void *)base;
-		Phdr *ph = (void *)(base + eh->e_phoff);
-		size_t phnum = eh->e_phnum;
-		size_t phent = eh->e_phentsize;
-		while (phnum-- && ph->p_type != PT_DYNAMIC)
-			ph = (void *)((size_t)ph + phent);
-		dynv = (void *)(base + ph->p_vaddr);
-	}
-#endif
-
-	for (i=0; i<DYN_CNT; i++) dyn[i] = 0;
-	for (i=0; dynv[i]; i+=2) if (dynv[i]<DYN_CNT)
-		dyn[dynv[i]] = dynv[i+1];
-
-#if DL_FDPIC
-	for (i=0; i<DYN_CNT; i++) {
-		if (i==DT_RELASZ || i==DT_RELSZ) continue;
-		if (!dyn[i]) continue;
-		for (j=0; dyn[i]-segs[j].p_vaddr >= segs[j].p_memsz; j++);
-		dyn[i] += segs[j].addr - segs[j].p_vaddr;
-	}
-	base = 0;
-
-	const Sym *syms = (void *)dyn[DT_SYMTAB];
-
-	rel = (void *)dyn[DT_RELA];
-	rel_size = dyn[DT_RELASZ];
-	for (; rel_size; rel+=3, rel_size-=3*sizeof(size_t)) {
-		if (!IS_RELATIVE(rel[1], syms)) continue;
-		for (j=0; rel[0]-segs[j].p_vaddr >= segs[j].p_memsz; j++);
-		size_t *rel_addr = (void *)
-			(rel[0] + segs[j].addr - segs[j].p_vaddr);
-		if (R_TYPE(rel[1]) == REL_FUNCDESC_VAL) {
-			*rel_addr += segs[rel_addr[1]].addr
-				- segs[rel_addr[1]].p_vaddr
-				+ syms[R_SYM(rel[1])].st_value;
-			rel_addr[1] = dyn[DT_PLTGOT];
-		} else {
-			size_t val = syms[R_SYM(rel[1])].st_value;
-			for (j=0; val-segs[j].p_vaddr >= segs[j].p_memsz; j++);
-			*rel_addr = rel[2] + segs[j].addr - segs[j].p_vaddr + val;
-		}
-	}
-#else
-	/* If the dynamic linker is invoked as a command, its load
-	 * address is not available in the aux vector. Instead, compute
-	 * the load address as the difference between &_DYNAMIC and the
-	 * virtual address in the PT_DYNAMIC program header. */
-	base = aux[AT_BASE];
-	if (!base) {
-		size_t phnum = aux[AT_PHNUM];
-		size_t phentsize = aux[AT_PHENT];
-		Phdr *ph = (void *)aux[AT_PHDR];
-		for (i=phnum; i--; ph = (void *)((char *)ph + phentsize)) {
-			if (ph->p_type == PT_DYNAMIC) {
-				base = (size_t)dynv - ph->p_vaddr;
-				break;
-			}
-		}
-	}
-
-	/* MIPS uses an ugly packed form for GOT relocations. Since we
-	 * can't make function calls yet and the code is tiny anyway,
-	 * it's simply inlined here. */
-	if (NEED_MIPS_GOT_RELOCS) {
-		size_t local_cnt = 0;
-		size_t *got = (void *)(base + dyn[DT_PLTGOT]);
-		for (i=0; dynv[i]; i+=2) if (dynv[i]==DT_MIPS_LOCAL_GOTNO)
-			local_cnt = dynv[i+1];
-		for (i=0; i<local_cnt; i++) got[i] += base;
-	}
-
-	rel = (void *)(base+dyn[DT_REL]);
-	rel_size = dyn[DT_RELSZ];
-	for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t)) {
-		if (!IS_RELATIVE(rel[1], 0)) continue;
-		size_t *rel_addr = (void *)(base + rel[0]);
-		*rel_addr += base;
-	}
-
-	rel = (void *)(base+dyn[DT_RELA]);
-	rel_size = dyn[DT_RELASZ];
-	for (; rel_size; rel+=3, rel_size-=3*sizeof(size_t)) {
-		if (!IS_RELATIVE(rel[1], 0)) continue;
-		size_t *rel_addr = (void *)(base + rel[0]);
-		*rel_addr = base + rel[2];
-	}
-#endif
-
-	stage2_func dls2;
-	GETFUNCSYM(&dls2, __dls2, base+dyn[DT_PLTGOT]);
-	dls2((void *)base, sp);
-}
-
-#endif