| /* |
| 13 Dec '05 |
| Linker no longer used - apart from mymalloc(). |
| Instead, simply compile and link switchback.c with test_xxx.c, e.g.: |
| ./> (cd .. && make EXTRA_CFLAGS="-m64" libvex_ppc64_linux.a) && gcc -m64 -Wall -O -g -o switchback switchback.c linker.c ../libvex_ppc64_linux.a test_bzip2.c |
| */ |
| |
| |
| #include <stdlib.h> |
| #include <stdio.h> |
| #include <assert.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <unistd.h> |
| #include <elf.h> |
| #include <fcntl.h> |
| #include <string.h> |
| //#include <malloc.h> |
| |
| #include "linker.h" |
| |
| #include "../pub/libvex_basictypes.h" |
| |
| #if 0 |
| #define IF_DEBUG(x,y) /* */ |
| static int debug_linker = 0; |
| #endif |
| |
| |
| #if defined(__x86_64__) |
| # define x86_64_TARGET_ARCH |
| #elif defined(__i386__) |
| # define i386_TARGET_ARCH |
| #elif defined (__powerpc__) |
| # define ppc32_TARGET_ARCH |
| #elif defined(__aarch64__) |
| # define arm64_TARGET_ARCH |
| #else |
| # error "Unknown arch" |
| #endif |
| |
| |
| #if 0 |
| #define CALLOC_MAX 10000000 |
| static HChar calloc_area[CALLOC_MAX]; |
| static UInt calloc_used = 0; |
| static void* calloc_below2G ( Int n, Int m ) |
| { |
| void* p; |
| int i; |
| while ((calloc_used % 16) > 0) calloc_used++; |
| assert(calloc_used + n*m < CALLOC_MAX); |
| p = &calloc_area[calloc_used]; |
| for (i = 0; i < n*m; i++) |
| calloc_area[calloc_used+i] = 0; |
| calloc_used += n*m; |
| return p; |
| } |
| #endif |
| |
| #define MYMALLOC_MAX 50*1000*1000 |
| static HChar mymalloc_area[MYMALLOC_MAX]; |
| static UInt mymalloc_used = 0; |
| void* mymalloc ( Int n ) |
| { |
| void* p; |
| #if defined(__powerpc64__) || defined(__aarch64__) |
| while ((ULong)(mymalloc_area+mymalloc_used) & 0xFFF) |
| #else |
| while ((UInt)(mymalloc_area+mymalloc_used) & 0xFFF) |
| #endif |
| mymalloc_used++; |
| assert(mymalloc_used+n < MYMALLOC_MAX); |
| p = (void*)(&mymalloc_area[mymalloc_used]); |
| mymalloc_used += n; |
| // printf("mymalloc(%d) = %p\n", n, p); |
| return p; |
| } |
| |
| void myfree ( void* p ) |
| { |
| } |
| |
| |
| |
| |
| |
| |
| |
| #if 0 |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // TYPES |
| |
| #define FALSE 0 |
| #define TRUE 1 |
| |
| typedef enum { OBJECT_LOADED, OBJECT_RESOLVED } OStatus; |
| |
| |
| #define N_FIXUP_PAGES 1 |
| |
| |
| /* Indication of section kinds for loaded objects. Needed by |
| the GC for deciding whether or not a pointer on the stack |
| is a code pointer. |
| */ |
| typedef |
| enum { SECTIONKIND_CODE_OR_RODATA, |
| SECTIONKIND_RWDATA, |
| SECTIONKIND_OTHER, |
| SECTIONKIND_NOINFOAVAIL } |
| SectionKind; |
| |
| typedef |
| struct _Section { |
| void* start; |
| void* end; |
| SectionKind kind; |
| struct _Section* next; |
| } |
| Section; |
| |
| typedef |
| struct _ProddableBlock { |
| void* start; |
| int size; |
| struct _ProddableBlock* next; |
| } |
| ProddableBlock; |
| |
| /* Top-level structure for an object module. One of these is allocated |
| * for each object file in use. |
| */ |
| typedef struct _ObjectCode { |
| OStatus status; |
| char* fileName; |
| int fileSize; |
| char* formatName; /* eg "ELF32", "DLL", "COFF", etc. */ |
| |
| /* An array containing ptrs to all the symbol names copied from |
| this object into the global symbol hash table. This is so that |
| we know which parts of the latter mapping to nuke when this |
| object is removed from the system. */ |
| char** symbols; |
| int n_symbols; |
| |
| /* ptr to malloc'd lump of memory holding the obj file */ |
| void* image; |
| |
| /* Fixup area for long-distance jumps. */ |
| char* fixup; |
| int fixup_used; |
| int fixup_size; |
| |
| /* The section-kind entries for this object module. Linked |
| list. */ |
| Section* sections; |
| |
| /* A private hash table for local symbols. */ |
| /* HashTable* */ void* lochash; |
| |
| /* Allow a chain of these things */ |
| struct _ObjectCode * next; |
| |
| /* SANITY CHECK ONLY: a list of the only memory regions which may |
| safely be prodded during relocation. Any attempt to prod |
| outside one of these is an error in the linker. */ |
| ProddableBlock* proddables; |
| |
| } ObjectCode; |
| |
| /* |
| * Define a set of types which can be used for both ELF32 and ELF64 |
| */ |
| |
| #if VEX_HOST_WORDSIZE == 8 |
| #define ELFCLASS ELFCLASS64 |
| #define Elf_Addr Elf64_Addr |
| #define Elf_Word Elf64_Word |
| #define Elf_Sword Elf64_Sword |
| #define Elf_Ehdr Elf64_Ehdr |
| #define Elf_Phdr Elf64_Phdr |
| #define Elf_Shdr Elf64_Shdr |
| #define Elf_Sym Elf64_Sym |
| #define Elf_Rel Elf64_Rel |
| #define Elf_Rela Elf64_Rela |
| #define ELF_ST_TYPE ELF64_ST_TYPE |
| #define ELF_ST_BIND ELF64_ST_BIND |
| #define ELF_R_TYPE ELF64_R_TYPE |
| #define ELF_R_SYM ELF64_R_SYM |
| #else |
| #define ELFCLASS ELFCLASS32 |
| #define Elf_Addr Elf32_Addr |
| #define Elf_Word Elf32_Word |
| #define Elf_Sword Elf32_Sword |
| #define Elf_Ehdr Elf32_Ehdr |
| #define Elf_Phdr Elf32_Phdr |
| #define Elf_Shdr Elf32_Shdr |
| #define Elf_Sym Elf32_Sym |
| #define Elf_Rel Elf32_Rel |
| #define Elf_Rela Elf32_Rela |
| #ifndef ELF_ST_TYPE |
| #define ELF_ST_TYPE ELF32_ST_TYPE |
| #endif |
| #ifndef ELF_ST_BIND |
| #define ELF_ST_BIND ELF32_ST_BIND |
| #endif |
| #ifndef ELF_R_TYPE |
| #define ELF_R_TYPE ELF32_R_TYPE |
| #endif |
| #ifndef ELF_R_SYM |
| #define ELF_R_SYM ELF32_R_SYM |
| #endif |
| #endif |
| |
| |
| |
| |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // PARANOIA |
| |
| /* ----------------------------------------------------------------------- |
| * Sanity checking. For each ObjectCode, maintain a list of address ranges |
| * which may be prodded during relocation, and abort if we try and write |
| * outside any of these. |
| */ |
| static void addProddableBlock ( ObjectCode* oc, void* start, int size ) |
| { |
| ProddableBlock* pb |
| = mymalloc(sizeof(ProddableBlock)); |
| if (debug_linker) |
| fprintf(stderr, "aPB oc=%p %p %d (%p .. %p)\n", oc, start, size, |
| start, ((char*)start)+size-1 ); |
| assert(size > 0); |
| pb->start = start; |
| pb->size = size; |
| pb->next = oc->proddables; |
| oc->proddables = pb; |
| } |
| |
| static void checkProddableBlock ( ObjectCode* oc, void* addr ) |
| { |
| ProddableBlock* pb; |
| for (pb = oc->proddables; pb != NULL; pb = pb->next) { |
| char* s = (char*)(pb->start); |
| char* e = s + pb->size - 1; |
| char* a = (char*)addr; |
| /* Assumes that the biggest fixup involves a 4-byte write. This |
| probably needs to be changed to 8 (ie, +7) on 64-bit |
| plats. */ |
| if (a >= s && (a+3) <= e) return; |
| } |
| fprintf(stderr, |
| "checkProddableBlock: invalid fixup %p in runtime linker\n", |
| addr); |
| exit(1); |
| } |
| |
| |
| |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // String->Addr mappings |
| |
| typedef |
| struct { char* mp_name; void* mp_addr; } |
| Maplet; |
| |
| typedef |
| struct { |
| int sm_size; |
| int sm_used; |
| Maplet* maplets; |
| } |
| StringMap; |
| |
| static StringMap* new_StringMap ( void ) |
| { |
| StringMap* sm = mymalloc(sizeof(StringMap)); |
| sm->sm_size = 10; |
| sm->sm_used = 0; |
| sm->maplets = mymalloc(10 * sizeof(Maplet)); |
| return sm; |
| } |
| |
| static void delete_StringMap ( StringMap* sm ) |
| { |
| assert(sm->maplets != NULL); |
| myfree(sm->maplets); |
| sm->maplets = NULL; |
| myfree(sm); |
| } |
| |
| static void ensure_StringMap ( StringMap* sm ) |
| { |
| int i; |
| Maplet* mp2; |
| assert(sm->maplets != NULL); |
| if (sm->sm_used < sm->sm_size) |
| return; |
| sm->sm_size *= 2; |
| mp2 = mymalloc(sm->sm_size * sizeof(Maplet)); |
| for (i = 0; i < sm->sm_used; i++) |
| mp2[i] = sm->maplets[i]; |
| myfree(sm->maplets); |
| sm->maplets = mp2; |
| } |
| |
| static void* search_StringMap ( StringMap* sm, char* name ) |
| { |
| int i; |
| for (i = 0; i < sm->sm_used; i++) |
| if (0 == strcmp(name, sm->maplets[i].mp_name)) |
| return sm->maplets[i].mp_addr; |
| return NULL; |
| } |
| |
| static void addto_StringMap ( StringMap* sm, char* name, void* addr ) |
| { |
| ensure_StringMap(sm); |
| sm->maplets[sm->sm_used].mp_name = name; |
| sm->maplets[sm->sm_used].mp_addr = addr; |
| sm->sm_used++; |
| } |
| |
| static void paranoid_addto_StringMap ( StringMap* sm, char* name, void* addr ) |
| { |
| if (0) |
| fprintf(stderr, "paranoid_addto_StringMap(%s,%p)\n", name, addr); |
| if (search_StringMap(sm,name) != NULL) { |
| fprintf(stderr, "duplicate: paranoid_addto_StringMap(%s,%p)\n", name, addr); |
| exit(1); |
| } |
| addto_StringMap(sm,name,addr); |
| } |
| |
| |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // Top-level linker control. |
| |
| StringMap* global_symbol_table = NULL; |
| ObjectCode* global_object_list = NULL; |
| |
| static void initLinker ( void ) |
| { |
| if (global_symbol_table != NULL) |
| return; |
| global_symbol_table = new_StringMap(); |
| } |
| |
| |
| |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // SYMBOL TABLE(s) |
| |
| /* ----------------------------------------------------------------- |
| * lookup a symbol in the global symbol table |
| */ |
| static |
| void * lookupSymbol( char *lbl ) |
| { |
| void *val; |
| initLinker() ; |
| assert(global_symbol_table != NULL); |
| val = search_StringMap(global_symbol_table, lbl); |
| return val; |
| } |
| |
| |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // HELPERS |
| |
| /* |
| * Generic ELF functions |
| */ |
| |
| static char * |
| findElfSection ( void* objImage, Elf_Word sh_type ) |
| { |
| char* ehdrC = (char*)objImage; |
| Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC; |
| Elf_Shdr* shdr = (Elf_Shdr*)(ehdrC + ehdr->e_shoff); |
| char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset; |
| char* ptr = NULL; |
| int i; |
| |
| for (i = 0; i < ehdr->e_shnum; i++) { |
| if (shdr[i].sh_type == sh_type |
| /* Ignore the section header's string table. */ |
| && i != ehdr->e_shstrndx |
| /* Ignore string tables named .stabstr, as they contain |
| debugging info. */ |
| && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8) |
| ) { |
| ptr = ehdrC + shdr[i].sh_offset; |
| break; |
| } |
| } |
| return ptr; |
| } |
| |
| #ifdef arm_TARGET_ARCH |
| static |
| char* alloc_fixup_bytes ( ObjectCode* oc, int nbytes ) |
| { |
| char* res; |
| assert(nbytes % 4 == 0); |
| assert(nbytes > 0); |
| res = &(oc->fixup[oc->fixup_used]); |
| oc->fixup_used += nbytes; |
| if (oc->fixup_used >= oc->fixup_size) { |
| fprintf(stderr, "fixup area too small for %s\n", oc->fileName); |
| exit(1); |
| } |
| return res; |
| } |
| #endif |
| |
| |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // RESOLVE |
| |
| static |
| void* lookup_magic_hacks ( char* sym ) |
| { |
| if (0==strcmp(sym, "printf")) return (void*)(&printf); |
| return NULL; |
| } |
| |
| #ifdef arm_TARGET_ARCH |
| static |
| void arm_notify_new_code ( char* start, int length ) |
| { |
| __asm __volatile ("mov r1, %0\n\t" |
| "mov r2, %1\n\t" |
| "mov r3, %2\n\t" |
| "swi 0x9f0002\n\t" |
| : |
| : "ir" (start), "ir" (length), "ir" (0) ); |
| } |
| |
| |
| static |
| void gen_armle_goto ( char* fixup, char* dstP ) |
| { |
| Elf_Word w = (Elf_Word)dstP; |
| /* |
| 2 .text |
| 3 0000 04F01FE5 ldr pc, value |
| 4 0004 44332211 value: .word 0x11223344 |
| */ |
| fprintf(stderr,"at %p generating jump to %p\n", fixup, dstP ); |
| fixup[0] = 0x04; fixup[1] = 0xF0; fixup[2] = 0x1F; fixup[3] = 0xE5; |
| fixup[4] = w & 0xFF; w >>= 8; |
| fixup[5] = w & 0xFF; w >>= 8; |
| fixup[6] = w & 0xFF; w >>= 8; |
| fixup[7] = w & 0xFF; w >>= 8; |
| arm_notify_new_code(fixup, 8); |
| } |
| #endif /* arm_TARGET_ARCH */ |
| |
| |
| #ifdef ppc32_TARGET_ARCH |
| static void invalidate_icache(void *ptr, int nbytes) |
| { |
| unsigned long startaddr = (unsigned long) ptr; |
| unsigned long endaddr = startaddr + nbytes; |
| unsigned long addr; |
| unsigned long cls = 16; //VG_(cache_line_size); |
| |
| startaddr &= ~(cls - 1); |
| for (addr = startaddr; addr < endaddr; addr += cls) |
| asm volatile("dcbst 0,%0" : : "r" (addr)); |
| asm volatile("sync"); |
| for (addr = startaddr; addr < endaddr; addr += cls) |
| asm volatile("icbi 0,%0" : : "r" (addr)); |
| asm volatile("sync; isync"); |
| } |
| |
| static UInt compute_ppc_HA ( UInt x ) { |
| return 0xFFFF & ( (x >> 16) + ((x & 0x8000) ? 1 : 0) ); |
| } |
| static UInt compute_ppc_LO ( UInt x ) { |
| return 0xFFFF & x; |
| } |
| static UInt compute_ppc_HI ( UInt x ) { |
| return 0xFFFF & (x >> 16); |
| } |
| #endif /* ppc32_TARGET_ARCH */ |
| |
| |
| /* Do ELF relocations which lack an explicit addend. All x86-linux |
| relocations appear to be of this form. */ |
| static int |
| do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC, |
| Elf_Shdr* shdr, int shnum, |
| Elf_Sym* stab, char* strtab ) |
| { |
| int j; |
| char *symbol = NULL; |
| Elf_Word* targ; |
| Elf_Rel* rtab = (Elf_Rel*) (ehdrC + shdr[shnum].sh_offset); |
| int nent = shdr[shnum].sh_size / sizeof(Elf_Rel); |
| int target_shndx = shdr[shnum].sh_info; |
| int symtab_shndx = shdr[shnum].sh_link; |
| |
| stab = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset); |
| targ = (Elf_Word*)(ehdrC + shdr[ target_shndx ].sh_offset); |
| IF_DEBUG(linker,belch( "relocations for section %d using symtab %d", |
| target_shndx, symtab_shndx )); |
| |
| for (j = 0; j < nent; j++) { |
| Elf_Addr offset = rtab[j].r_offset; |
| Elf_Addr info = rtab[j].r_info; |
| |
| Elf_Addr P = ((Elf_Addr)targ) + offset; |
| Elf_Word* pP = (Elf_Word*)P; |
| Elf_Addr A = *pP; |
| Elf_Addr S; |
| Elf_Addr value; |
| |
| IF_DEBUG(linker,belch( "Rel entry %3d is raw(%6p %6p)", |
| j, (void*)offset, (void*)info )); |
| if (!info) { |
| IF_DEBUG(linker,belch( " ZERO" )); |
| S = 0; |
| } else { |
| Elf_Sym sym = stab[ELF_R_SYM(info)]; |
| /* First see if it is a local symbol. */ |
| if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) { |
| /* Yes, so we can get the address directly from the ELF symbol |
| table. */ |
| symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name; |
| S = (Elf_Addr) |
| (ehdrC + shdr[ sym.st_shndx ].sh_offset |
| + stab[ELF_R_SYM(info)].st_value); |
| |
| } else { |
| /* No, so look up the name in our global table. */ |
| symbol = strtab + sym.st_name; |
| S = (Elf_Addr)lookupSymbol( symbol ); |
| } |
| if (!S) { |
| S = (Elf_Addr)lookup_magic_hacks(symbol); |
| } |
| if (!S) { |
| fprintf(stderr,"%s: unknown symbol `%s'\n", |
| oc->fileName, symbol); |
| return 0; |
| } |
| if (debug_linker>1) |
| fprintf(stderr, "\n`%s' resolves to %p\n", symbol, (void*)S ); |
| } |
| |
| if (debug_linker>1) |
| fprintf(stderr, "Reloc: P = %p S = %p A = %p\n", |
| (void*)P, (void*)S, (void*)A ); |
| checkProddableBlock ( oc, pP ); |
| |
| value = S + A; |
| |
| switch (ELF_R_TYPE(info)) { |
| # ifdef i386_TARGET_ARCH |
| case R_386_32: *pP = value; break; |
| case R_386_PC32: *pP = value - P; break; |
| # endif |
| # ifdef arm_TARGET_ARCH |
| case R_ARM_PC24: { |
| Elf_Word w, delta, deltaTop8; |
| /* Generate a jump sequence into the fixup area |
| and branch to that instead. */ |
| char* fixup = alloc_fixup_bytes(oc, 8); |
| /* First of all, figure out where we're really trying to |
| jump to. */ |
| // compensate for pc+8 bias |
| Elf_Word real_dst = (A & 0x00FFFFFF) + 2; |
| // sign-extend 24-to-32 of real_dst |
| if (real_dst & 0x00800000) |
| real_dst |= 0xFF000000; |
| else |
| real_dst &= 0x00FFFFFF; |
| |
| real_dst <<= 2; |
| real_dst += S; |
| |
| gen_armle_goto(fixup, (char*)real_dst); |
| |
| /* Delta is in bytes .. */ |
| delta = (((Elf_Word)fixup) - ((Elf_Word)pP) - 8); |
| deltaTop8 = (delta >> 24) & 0xFF; |
| if (deltaTop8 != 0 && deltaTop8 != 0xFF) { |
| fprintf(stderr,"R_ARM_PC24: out of range delta 0x%x for %s\n", |
| delta, symbol); |
| exit(1); |
| } |
| delta >>= 2; |
| w = *pP; |
| w &= 0xFF000000; |
| w |= (0x00FFFFFF & delta ); |
| *pP = w; |
| break; |
| } |
| case R_ARM_ABS32: |
| *pP = value; |
| break; |
| # endif |
| default: |
| fprintf(stderr, |
| "%s: unhandled ELF relocation(Rel) type %d\n\n", |
| oc->fileName, (Int)ELF_R_TYPE(info)); |
| return 0; |
| } |
| |
| } |
| return 1; |
| } |
| |
| /* Do ELF relocations for which explicit addends are supplied. |
| sparc-solaris relocations appear to be of this form. */ |
| static int |
| do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC, |
| Elf_Shdr* shdr, int shnum, |
| Elf_Sym* stab, char* strtab ) |
| { |
| int j; |
| char *symbol; |
| Elf_Addr targ; |
| Elf_Rela* rtab = (Elf_Rela*) (ehdrC + shdr[shnum].sh_offset); |
| int nent = shdr[shnum].sh_size / sizeof(Elf_Rela); |
| int target_shndx = shdr[shnum].sh_info; |
| int symtab_shndx = shdr[shnum].sh_link; |
| |
| stab = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset); |
| targ = (Elf_Addr) (ehdrC + shdr[ target_shndx ].sh_offset); |
| IF_DEBUG(linker,belch( "relocations for section %d using symtab %d", |
| target_shndx, symtab_shndx )); |
| |
| for (j = 0; j < nent; j++) { |
| #if defined(DEBUG) || defined(sparc_TARGET_ARCH) \ |
| || defined(ia64_TARGET_ARCH) \ |
| || defined(x86_64_TARGET_ARCH) \ |
| || defined(ppc32_TARGET_ARCH) |
| /* This #ifdef only serves to avoid unused-var warnings. */ |
| Elf_Addr offset = rtab[j].r_offset; |
| Elf_Addr P = targ + offset; |
| #endif |
| Elf_Addr info = rtab[j].r_info; |
| Elf_Addr A = rtab[j].r_addend; |
| Elf_Addr S =0; |
| Elf_Addr value; |
| # if defined(sparc_TARGET_ARCH) |
| Elf_Word* pP = (Elf_Word*)P; |
| Elf_Word w1, w2; |
| # endif |
| # if defined(ia64_TARGET_ARCH) |
| Elf64_Xword *pP = (Elf64_Xword *)P; |
| Elf_Addr addr; |
| # endif |
| # if defined(x86_64_TARGET_ARCH) |
| ULong* pP = (ULong*)P; |
| # endif |
| # if defined(ppc32_TARGET_ARCH) |
| Int sI, sI2; |
| Elf_Word* pP = (Elf_Word*)P; |
| # endif |
| |
| IF_DEBUG(linker,belch( "Rel entry %3d is raw(%6p %6p %6p) ", |
| j, (void*)offset, (void*)info, |
| (void*)A )); |
| if (!info) { |
| IF_DEBUG(linker,belch( " ZERO" )); |
| S = 0; |
| } else { |
| Elf_Sym sym = stab[ELF_R_SYM(info)]; |
| /* First see if it is a local symbol. */ |
| if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) { |
| /* Yes, so we can get the address directly from the ELF symbol |
| table. */ |
| symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name; |
| S = (Elf_Addr) |
| (ehdrC + shdr[ sym.st_shndx ].sh_offset |
| + stab[ELF_R_SYM(info)].st_value); |
| #ifdef ELF_FUNCTION_DESC |
| /* Make a function descriptor for this function */ |
| if (S && ELF_ST_TYPE(sym.st_info) == STT_FUNC) { |
| S = allocateFunctionDesc(S + A); |
| A = 0; |
| } |
| #endif |
| } else { |
| /* No, so look up the name in our global table. */ |
| symbol = strtab + sym.st_name; |
| S = (Elf_Addr)lookupSymbol( symbol ); |
| |
| #ifdef ELF_FUNCTION_DESC |
| /* If a function, already a function descriptor - we would |
| have to copy it to add an offset. */ |
| if (S && (ELF_ST_TYPE(sym.st_info) == STT_FUNC) && (A != 0)) |
| belch("%s: function %s with addend %p", oc->fileName, symbol, (void *)A); |
| #endif |
| } |
| if (!S) { |
| fprintf(stderr,"%s: unknown symbol `%s'\n", oc->fileName, symbol); |
| return 0; |
| } |
| if (0) |
| fprintf(stderr, "`%s' resolves to %p\n", symbol, (void*)S ); |
| } |
| |
| #if 0 |
| fprintf ( stderr, "Reloc: offset = %p P = %p S = %p A = %p\n", |
| (void*)offset, (void*)P, (void*)S, (void*)A ); |
| #endif |
| |
| /* checkProddableBlock ( oc, (void*)P ); */ |
| |
| value = S + A; |
| |
| switch (ELF_R_TYPE(info)) { |
| # if defined(sparc_TARGET_ARCH) |
| case R_SPARC_WDISP30: |
| w1 = *pP & 0xC0000000; |
| w2 = (Elf_Word)((value - P) >> 2); |
| ASSERT((w2 & 0xC0000000) == 0); |
| w1 |= w2; |
| *pP = w1; |
| break; |
| case R_SPARC_HI22: |
| w1 = *pP & 0xFFC00000; |
| w2 = (Elf_Word)(value >> 10); |
| ASSERT((w2 & 0xFFC00000) == 0); |
| w1 |= w2; |
| *pP = w1; |
| break; |
| case R_SPARC_LO10: |
| w1 = *pP & ~0x3FF; |
| w2 = (Elf_Word)(value & 0x3FF); |
| ASSERT((w2 & ~0x3FF) == 0); |
| w1 |= w2; |
| *pP = w1; |
| break; |
| /* According to the Sun documentation: |
| R_SPARC_UA32 |
| This relocation type resembles R_SPARC_32, except it refers to an |
| unaligned word. That is, the word to be relocated must be treated |
| as four separate bytes with arbitrary alignment, not as a word |
| aligned according to the architecture requirements. |
| |
| (JRS: which means that freeloading on the R_SPARC_32 case |
| is probably wrong, but hey ...) |
| */ |
| case R_SPARC_UA32: |
| case R_SPARC_32: |
| w2 = (Elf_Word)value; |
| *pP = w2; |
| break; |
| # endif |
| # if defined(ia64_TARGET_ARCH) |
| case R_IA64_DIR64LSB: |
| case R_IA64_FPTR64LSB: |
| *pP = value; |
| break; |
| case R_IA64_PCREL64LSB: |
| *pP = value - P; |
| break; |
| case R_IA64_SEGREL64LSB: |
| addr = findElfSegment(ehdrC, value); |
| *pP = value - addr; |
| break; |
| case R_IA64_GPREL22: |
| ia64_reloc_gprel22(P, value); |
| break; |
| case R_IA64_LTOFF22: |
| case R_IA64_LTOFF22X: |
| case R_IA64_LTOFF_FPTR22: |
| addr = allocateGOTEntry(value); |
| ia64_reloc_gprel22(P, addr); |
| break; |
| case R_IA64_PCREL21B: |
| ia64_reloc_pcrel21(P, S, oc); |
| break; |
| case R_IA64_LDXMOV: |
| /* This goes with R_IA64_LTOFF22X and points to the load to |
| convert into a move. We don't implement relaxation. */ |
| break; |
| # endif |
| # if defined(x86_64_TARGET_ARCH) |
| case R_X86_64_64: /* 1 *//* Direct 64 bit */ |
| *((ULong*)pP) = (ULong)(S + A); |
| break; |
| case R_X86_64_PC32: /* 2 *//* PC relative 32 bit signed */ |
| *((UInt*)pP) = (UInt)(S + A - P); |
| break; |
| case R_X86_64_32: /* 10 *//* Direct 32 bit zero extended */ |
| *((UInt*)pP) = (UInt)(S + A); |
| break; |
| case R_X86_64_32S: /* 11 *//* Direct 32 bit sign extended */ |
| *((UInt*)pP) = (UInt)(S + A); |
| break; |
| # endif |
| # if defined(ppc32_TARGET_ARCH) |
| case R_PPC_ADDR32: /* 1 *//* 32bit absolute address */ |
| *((UInt*)pP) = S+A; |
| invalidate_icache(pP,4); |
| break; |
| case R_PPC_ADDR16_LO: /* 4 *//* lower 16bit of absolute address */ |
| *((UInt*)pP) &= 0x0000FFFF; |
| *((UInt*)pP) |= 0xFFFF0000 & (compute_ppc_LO(S+A) << 16); |
| invalidate_icache(pP,4); |
| break; |
| case R_PPC_ADDR16_HA: /* 6 *//* adjusted high 16bit */ |
| *((UInt*)pP) &= 0x0000FFFF; |
| *((UInt*)pP) |= 0xFFFF0000 & (compute_ppc_HA(S+A) << 16); |
| invalidate_icache(pP,4); |
| break; |
| case R_PPC_REL24: /* 10 *//* PC relative 26 bit */ |
| sI = S+A-P; |
| sI >>= 2; |
| /* the top 9 bits of sI must be the same (all 0s or |
| all 1s) for this to be valid; else we have to fail. */ |
| sI2 = sI >> 23; /* 23 == 32 - 9 */ |
| if (sI2 != 0 && sI2 != 0xFFFFFFFF) { |
| fprintf(stderr, "%s: R_PPC_REL24 relocation failed\n", oc->fileName ); |
| return 0; |
| } |
| *((UInt*)pP) &= ~(0x00FFFFFF << 2); |
| *((UInt*)pP) |= (0xFFFFFF & sI) << 2; |
| invalidate_icache(pP,4); |
| break; |
| case R_PPC_REL32: /* 26 */ |
| *((UInt*)pP) = S+A-P; |
| invalidate_icache(pP,4); |
| break; |
| # endif |
| default: |
| fprintf(stderr, |
| "%s: unhandled ELF relocation(RelA) type %d\n", |
| oc->fileName, (Int)ELF_R_TYPE(info)); |
| return 0; |
| } |
| |
| } |
| return 1; |
| } |
| |
| |
| static int |
| ocResolve_ELF ( ObjectCode* oc ) |
| { |
| char *strtab; |
| int shnum, ok; |
| Elf_Sym* stab = NULL; |
| char* ehdrC = (char*)(oc->image); |
| Elf_Ehdr* ehdr = (Elf_Ehdr*) ehdrC; |
| Elf_Shdr* shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff); |
| char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset; |
| |
| /* first find "the" symbol table */ |
| stab = (Elf_Sym*) findElfSection ( ehdrC, SHT_SYMTAB ); |
| |
| /* also go find the string table */ |
| strtab = findElfSection ( ehdrC, SHT_STRTAB ); |
| |
| if (stab == NULL || strtab == NULL) { |
| fprintf(stderr,"%s: can't find string or symbol table\n", oc->fileName); |
| return 0; |
| } |
| |
| /* Process the relocation sections. */ |
| for (shnum = 0; shnum < ehdr->e_shnum; shnum++) { |
| |
| /* Skip sections called ".rel.stab". These appear to contain |
| relocation entries that, when done, make the stabs debugging |
| info point at the right places. We ain't interested in all |
| dat jazz, mun. */ |
| if (0 == memcmp(".rel.stab", sh_strtab + shdr[shnum].sh_name, 9)) |
| continue; |
| |
| if (shdr[shnum].sh_type == SHT_REL ) { |
| ok = do_Elf_Rel_relocations ( oc, ehdrC, shdr, |
| shnum, stab, strtab ); |
| if (!ok) return ok; |
| } |
| else |
| if (shdr[shnum].sh_type == SHT_RELA) { |
| ok = do_Elf_Rela_relocations ( oc, ehdrC, shdr, |
| shnum, stab, strtab ); |
| if (!ok) return ok; |
| } |
| } |
| |
| /* Free the local symbol table; we won't need it again. */ |
| delete_StringMap(oc->lochash); |
| oc->lochash = NULL; |
| |
| return 1; |
| } |
| |
| |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // VERIFY |
| |
| static int |
| ocVerifyImage_ELF ( ObjectCode* oc ) |
| { |
| Elf_Shdr* shdr; |
| Elf_Sym* stab; |
| int i, j, nent, nstrtab, nsymtabs; |
| char* sh_strtab; |
| char* strtab; |
| |
| char* ehdrC = (char*)(oc->image); |
| Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC; |
| |
| if (ehdr->e_ident[EI_MAG0] != ELFMAG0 || |
| ehdr->e_ident[EI_MAG1] != ELFMAG1 || |
| ehdr->e_ident[EI_MAG2] != ELFMAG2 || |
| ehdr->e_ident[EI_MAG3] != ELFMAG3) { |
| fprintf(stderr,"%s: not an ELF object\n", oc->fileName); |
| return 0; |
| } |
| |
| if (ehdr->e_ident[EI_CLASS] != ELFCLASS) { |
| fprintf(stderr,"%s: unsupported ELF format\n", oc->fileName); |
| return 0; |
| } |
| |
| if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) { |
| if (debug_linker) |
| fprintf(stderr, "Is little-endian\n" ); |
| } else |
| if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) { |
| if (debug_linker) |
| fprintf(stderr, "Is big-endian\n" ); |
| } else { |
| fprintf(stderr,"%s: unknown endiannness\n", oc->fileName); |
| return 0; |
| } |
| |
| if (ehdr->e_type != ET_REL) { |
| fprintf(stderr,"%s: not a relocatable object (.o) file\n", oc->fileName); |
| return 0; |
| } |
| if (debug_linker) |
| fprintf(stderr, "Is a relocatable object (.o) file\n" ); |
| |
| if (debug_linker) |
| fprintf(stderr, "Architecture is " ); |
| switch (ehdr->e_machine) { |
| case EM_386: if (debug_linker) fprintf(stderr, "x86\n" ); break; |
| case EM_SPARC: if (debug_linker) fprintf(stderr, "sparc\n" ); break; |
| case EM_ARM: if (debug_linker) fprintf(stderr, "arm\n" ); break; |
| #ifdef EM_IA_64 |
| case EM_IA_64: if (debug_linker) fprintf(stderr, "ia64\n" ); break; |
| #endif |
| case EM_X86_64: if (debug_linker) fprintf(stderr, "x86_64\n" ); break; |
| case EM_PPC: if (debug_linker) fprintf(stderr, "ppc\n" ); break; |
| default: if (debug_linker) fprintf(stderr, "unknown\n" ); |
| fprintf(stderr,"%s: unknown architecture\n", oc->fileName); |
| return 0; |
| } |
| |
| if (debug_linker>1) fprintf(stderr, |
| "\nSection header table: start %lld, n_entries %d, ent_size %d\n", |
| (Long)ehdr->e_shoff, |
| ehdr->e_shnum, ehdr->e_shentsize ); |
| |
| assert (ehdr->e_shentsize == sizeof(Elf_Shdr)); |
| |
| shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff); |
| |
| if (ehdr->e_shstrndx == SHN_UNDEF) { |
| fprintf(stderr,"%s: no section header string table\n", oc->fileName); |
| return 0; |
| } else { |
| if (debug_linker>1) |
| fprintf(stderr, "Section header string table is section %d\n", |
| ehdr->e_shstrndx); |
| sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset; |
| } |
| |
| for (i = 0; i < ehdr->e_shnum; i++) { |
| if (debug_linker>1) fprintf(stderr, "%2d: ", i ); |
| if (debug_linker>1) fprintf(stderr, "type=%2d ", (int)shdr[i].sh_type ); |
| if (debug_linker>1) fprintf(stderr, "size=%4d ", (int)shdr[i].sh_size ); |
| if (debug_linker>1) fprintf(stderr, "offs=%4d ", (int)shdr[i].sh_offset ); |
| if (debug_linker>1) fprintf(stderr, " (%p .. %p) ", |
| ehdrC + shdr[i].sh_offset, |
| ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1); |
| |
| if (shdr[i].sh_type == SHT_REL) { |
| if (debug_linker>1) fprintf(stderr, "Rel " ); |
| } else if (shdr[i].sh_type == SHT_RELA) { |
| if (debug_linker>1) fprintf(stderr, "RelA " ); |
| } else { |
| if (debug_linker>1) fprintf(stderr," "); |
| } |
| if (sh_strtab) { |
| if (debug_linker>1) fprintf(stderr, "sname=%s\n", |
| sh_strtab + shdr[i].sh_name ); |
| } |
| } |
| |
| if (debug_linker>1) fprintf(stderr, "\nString tables\n" ); |
| strtab = NULL; |
| nstrtab = 0; |
| for (i = 0; i < ehdr->e_shnum; i++) { |
| if (shdr[i].sh_type == SHT_STRTAB |
| /* Ignore the section header's string table. */ |
| && i != ehdr->e_shstrndx |
| /* Ignore string tables named .stabstr, as they contain |
| debugging info. */ |
| && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8) |
| ) { |
| if (debug_linker>1) |
| fprintf(stderr," section %d is a normal string table\n", i ); |
| strtab = ehdrC + shdr[i].sh_offset; |
| nstrtab++; |
| } |
| } |
| if (nstrtab != 1) { |
| fprintf(stderr,"%s: no string tables, or too many\n", oc->fileName); |
| return 0; |
| } |
| |
| nsymtabs = 0; |
| if (debug_linker>1) fprintf(stderr, "\nSymbol tables\n" ); |
| for (i = 0; i < ehdr->e_shnum; i++) { |
| if (shdr[i].sh_type != SHT_SYMTAB) continue; |
| if (debug_linker>1) fprintf(stderr, "section %d is a symbol table\n", i ); |
| nsymtabs++; |
| stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset); |
| nent = shdr[i].sh_size / sizeof(Elf_Sym); |
| if (debug_linker>1) fprintf(stderr, |
| " number of entries is apparently %d (%lld rem)\n", |
| nent, |
| (Long)(shdr[i].sh_size % sizeof(Elf_Sym)) |
| ); |
| if (0 != shdr[i].sh_size % sizeof(Elf_Sym)) { |
| fprintf(stderr,"%s: non-integral number of symbol table entries\n", |
| oc->fileName); |
| return 0; |
| } |
| for (j = 0; j < nent; j++) { |
| if (debug_linker>1) fprintf(stderr, " %2d ", j ); |
| if (debug_linker>1) fprintf(stderr, " sec=%-5d size=%-3d val=%5p ", |
| (int)stab[j].st_shndx, |
| (int)stab[j].st_size, |
| (char*)stab[j].st_value ); |
| |
| if (debug_linker>1) fprintf(stderr, "type=" ); |
| switch (ELF_ST_TYPE(stab[j].st_info)) { |
| case STT_NOTYPE: if (debug_linker>1) fprintf(stderr, "notype " ); break; |
| case STT_OBJECT: if (debug_linker>1) fprintf(stderr, "object " ); break; |
| case STT_FUNC : if (debug_linker>1) fprintf(stderr, "func " ); break; |
| case STT_SECTION: if (debug_linker>1) fprintf(stderr, "section" ); break; |
| case STT_FILE: if (debug_linker>1) fprintf(stderr, "file " ); break; |
| default: if (debug_linker>1) fprintf(stderr, "? " ); break; |
| } |
| if (debug_linker>1) fprintf(stderr, " " ); |
| |
| if (debug_linker>1) fprintf(stderr, "bind=" ); |
| switch (ELF_ST_BIND(stab[j].st_info)) { |
| case STB_LOCAL : if (debug_linker>1) fprintf(stderr, "local " ); break; |
| case STB_GLOBAL: if (debug_linker>1) fprintf(stderr, "global" ); break; |
| case STB_WEAK : if (debug_linker>1) fprintf(stderr, "weak " ); break; |
| default: if (debug_linker>1) fprintf(stderr, "? " ); break; |
| } |
| if (debug_linker>1) fprintf(stderr, " " ); |
| |
| if (debug_linker>1) fprintf(stderr, "name=%s\n", strtab + stab[j].st_name ); |
| } |
| } |
| |
| if (nsymtabs == 0) { |
| fprintf(stderr,"%s: didn't find any symbol tables\n", oc->fileName); |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // GETNAMES |
| |
| static int |
| ocGetNames_ELF ( ObjectCode* oc ) |
| { |
| int i, j, k, nent; |
| Elf_Sym* stab; |
| |
| char* ehdrC = (char*)(oc->image); |
| Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC; |
| char* strtab = findElfSection ( ehdrC, SHT_STRTAB ); |
| Elf_Shdr* shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff); |
| |
| char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset; |
| char* sec_name; |
| |
| assert(global_symbol_table != NULL); |
| |
| if (!strtab) { |
| fprintf(stderr,"%s: no strtab\n", oc->fileName); |
| return 0; |
| } |
| |
| k = 0; |
| for (i = 0; i < ehdr->e_shnum; i++) { |
| /* Figure out what kind of section it is. Logic derived from |
| Figure 1.14 ("Special Sections") of the ELF document |
| ("Portable Formats Specification, Version 1.1"). */ |
| Elf_Shdr hdr = shdr[i]; |
| SectionKind kind = SECTIONKIND_OTHER; |
| int is_bss = FALSE; |
| |
| if (hdr.sh_type == SHT_PROGBITS |
| && (hdr.sh_flags & SHF_ALLOC) && (hdr.sh_flags & SHF_EXECINSTR)) { |
| /* .text-style section */ |
| kind = SECTIONKIND_CODE_OR_RODATA; |
| } |
| else |
| if (hdr.sh_type == SHT_PROGBITS |
| && (hdr.sh_flags & SHF_ALLOC) && (hdr.sh_flags & SHF_WRITE)) { |
| /* .data-style section */ |
| kind = SECTIONKIND_RWDATA; |
| } |
| else |
| if (hdr.sh_type == SHT_PROGBITS |
| && (hdr.sh_flags & SHF_ALLOC) && !(hdr.sh_flags & SHF_WRITE)) { |
| /* .rodata-style section */ |
| kind = SECTIONKIND_CODE_OR_RODATA; |
| } |
| else |
| if (hdr.sh_type == SHT_NOBITS |
| && (hdr.sh_flags & SHF_ALLOC) && (hdr.sh_flags & SHF_WRITE)) { |
| /* .bss-style section */ |
| kind = SECTIONKIND_RWDATA; |
| is_bss = TRUE; |
| } |
| |
| if (is_bss && shdr[i].sh_size > 0) { |
| /* This is a non-empty .bss section. Allocate zeroed space for |
| it, and set its .sh_offset field such that |
| ehdrC + .sh_offset == addr_of_zeroed_space. */ |
| char* zspace = calloc(1, shdr[i].sh_size); |
| shdr[i].sh_offset = ((char*)zspace) - ((char*)ehdrC); |
| if (1) |
| fprintf(stderr, "BSS section at %p, size %lld\n", |
| zspace, (Long)shdr[i].sh_size); |
| } |
| |
| /* When loading objects compiled with -g, it seems there are |
| relocations in various debug-info sections. So we'd better |
| tell addProddableBlock to allow those bits to be prodded. */ |
| //fprintf(stderr, "ZZZZZZZZZZ %s\n", sh_strtab + hdr.sh_name); |
| sec_name = sh_strtab + shdr[i].sh_name; |
| if (kind == SECTIONKIND_OTHER |
| && (0 == strcmp(".debug_info", sec_name) |
| || 0 == strcmp(".debug_line", sec_name) |
| || 0 == strcmp(".debug_pubnames", sec_name) |
| || 0 == strcmp(".debug_aranges", sec_name) |
| || 0 == strcmp(".debug_frame", sec_name))) { |
| kind = SECTIONKIND_CODE_OR_RODATA; |
| } |
| |
| /* fill in the section info */ |
| if (kind != SECTIONKIND_OTHER && shdr[i].sh_size > 0) { |
| addProddableBlock(oc, ehdrC + shdr[i].sh_offset, shdr[i].sh_size); |
| //addSection(oc, kind, ehdrC + shdr[i].sh_offset, |
| // ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1); |
| } |
| |
| if (shdr[i].sh_type != SHT_SYMTAB) continue; |
| |
| /* copy stuff into this module's object symbol table */ |
| stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset); |
| nent = shdr[i].sh_size / sizeof(Elf_Sym); |
| |
| oc->n_symbols = nent; |
| oc->symbols = mymalloc(oc->n_symbols * sizeof(char*)); |
| |
| for (j = 0; j < nent; j++) { |
| |
| char isLocal = FALSE; /* avoids uninit-var warning */ |
| char* ad = NULL; |
| char* nm = strtab + stab[j].st_name; |
| int secno = stab[j].st_shndx; |
| |
| /* Figure out if we want to add it; if so, set ad to its |
| address. Otherwise leave ad == NULL. */ |
| |
| if (secno == SHN_COMMON) { |
| isLocal = FALSE; |
| # if defined(__x86_64__) |
| ad = calloc_below2G(1, stab[j].st_size); |
| # else |
| ad = calloc(1, stab[j].st_size); |
| # endif |
| // assert( (Addr)ad < 0xF0000000ULL ); |
| |
| if (0) |
| fprintf(stderr, "COMMON symbol, size %lld name %s allocd %p\n", |
| (Long)stab[j].st_size, nm, ad); |
| /* Pointless to do addProddableBlock() for this area, |
| since the linker should never poke around in it. */ |
| } |
| else |
| if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL |
| || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL |
| ) |
| /* and not an undefined symbol */ |
| && stab[j].st_shndx != SHN_UNDEF |
| /* and not in a "special section" */ |
| && stab[j].st_shndx < SHN_LORESERVE |
| && |
| /* and it's a not a section or string table or anything silly */ |
| ( ELF_ST_TYPE(stab[j].st_info)==STT_FUNC || |
| ELF_ST_TYPE(stab[j].st_info)==STT_OBJECT || |
| ELF_ST_TYPE(stab[j].st_info)==STT_NOTYPE |
| ) |
| ) { |
| /* Section 0 is the undefined section, hence > and not >=. */ |
| assert(secno > 0 && secno < ehdr->e_shnum); |
| /* |
| if (shdr[secno].sh_type == SHT_NOBITS) { |
| fprintf(stderr, " BSS symbol, size %d off %d name %s\n", |
| stab[j].st_size, stab[j].st_value, nm); |
| } |
| */ |
| ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value; |
| if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) { |
| isLocal = TRUE; |
| } else { |
| #ifdef ELF_FUNCTION_DESC |
| /* dlsym() and the initialisation table both give us function |
| * descriptors, so to be consistent we store function descriptors |
| * in the symbol table */ |
| if (ELF_ST_TYPE(stab[j].st_info) == STT_FUNC) |
| ad = (char *)allocateFunctionDesc((Elf_Addr)ad); |
| #endif |
| if (0|| debug_linker) |
| fprintf(stderr, "addOTabName(GLOB): %10p %s %s\n", |
| ad, oc->fileName, nm ); |
| isLocal = FALSE; |
| } |
| } |
| |
| /* And the decision is ... */ |
| |
| if (ad != NULL) { |
| assert(nm != NULL); |
| oc->symbols[j] = nm; |
| /* Acquire! */ |
| if (isLocal) { |
| /* Ignore entirely. */ |
| } else { |
| //ghciInsertStrHashTable(oc->fileName, global_symbol_table, nm, ad); |
| paranoid_addto_StringMap(global_symbol_table, nm, ad); |
| } |
| } else { |
| /* Skip. */ |
| if (debug_linker>1) fprintf(stderr, "skipping `%s'\n", |
| strtab + stab[j].st_name ); |
| /* |
| fprintf(stderr, |
| "skipping bind = %d, type = %d, shndx = %d `%s'\n", |
| (int)ELF_ST_BIND(stab[j].st_info), |
| (int)ELF_ST_TYPE(stab[j].st_info), |
| (int)stab[j].st_shndx, |
| strtab + stab[j].st_name |
| ); |
| */ |
| oc->symbols[j] = NULL; |
| } |
| |
| } |
| } |
| |
| return 1; |
| } |
| |
| |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////// |
| // |
| // TOP-LEVEL CONTROL OF THE LINKER |
| |
| |
| /* --------------------------------------------------------------------- |
| * Load an obj (populate the global symbol table, but don't resolve yet) |
| * |
| * Returns: 1 if ok, 0 on error. |
| */ |
| static |
| int loadObj( char *path ) |
| { |
| ObjectCode* oc; |
| struct stat st; |
| int r; |
| int fd, pagesize; |
| char* p; |
| |
| initLinker(); |
| |
| fprintf(stderr, "==== loadObj %s ====\n", path ); |
| |
| /* Check that we haven't already loaded this object. */ |
| { |
| ObjectCode *o; |
| int is_dup = 0; |
| for (o = global_object_list; o; o = o->next) { |
| if (0 == strcmp(o->fileName, path)) |
| is_dup = 1; |
| } |
| if (is_dup) { |
| fprintf(stderr, |
| "\n\n" |
| "GHCi runtime linker: warning: looks like you're trying to load the\n" |
| "same object file twice:\n" |
| " %s\n" |
| , path); |
| exit(1); |
| } |
| } |
| |
| oc = mymalloc(sizeof(ObjectCode)); |
| |
| oc->formatName = "ELF"; |
| |
| r = stat(path, &st); |
| if (r == -1) { return 0; } |
| |
| /* sigh, strdup() isn't a POSIX function, so do it the long way */ |
| oc->fileName = mymalloc( strlen(path)+1 ); |
| strcpy(oc->fileName, path); |
| |
| oc->fileSize = st.st_size; |
| oc->symbols = NULL; |
| oc->sections = NULL; |
| oc->lochash = new_StringMap(); |
| oc->proddables = NULL; |
| oc->fixup = NULL; |
| oc->fixup_used = 0; |
| oc->fixup_size = 0; |
| |
| /* chain it onto the list of objects */ |
| oc->next = global_object_list; |
| global_object_list = oc; |
| |
| fd = open(path, O_RDONLY); |
| if (fd == -1) { |
| fprintf(stderr,"loadObj: can't open `%s'\n", path); |
| exit(1); |
| } |
| |
| /* Allocate a 1-page area just prior to the image, so we can put |
| fixup code fragments there. Used for doing R_ARM_PC24 |
| relocations for jump distances > 64M. */ |
| |
| pagesize = getpagesize(); |
| // p = memalign(pagesize, N_FIXUP_PAGES * pagesize |
| // + oc->fileSize); |
| p = mymalloc(N_FIXUP_PAGES * pagesize + oc->fileSize); |
| if (0) fprintf(stderr,"XXXX p = %p\n", p); |
| if (p == NULL) { |
| fprintf(stderr,"loadObj: failed to allocate space for `%s'\n", path); |
| exit(1); |
| } |
| |
| oc->fixup = p; |
| oc->fixup_size = N_FIXUP_PAGES * pagesize; |
| oc->fixup_used = 0; |
| oc->image = &(p[ oc->fixup_size ]); |
| |
| r = read(fd, oc->image, oc->fileSize); |
| if (r != oc->fileSize) { |
| fprintf(stderr,"loadObj: failed to read `%s'\n", path); |
| exit(1); |
| } |
| |
| fprintf(stderr, "loaded %s at %p (fixup = %p)\n", |
| oc->fileName, oc->image, oc->fixup ); |
| |
| close(fd); |
| |
| /* verify the in-memory image */ |
| r = ocVerifyImage_ELF ( oc ); |
| if (!r) { return r; } |
| |
| /* build the symbol list for this image */ |
| r = ocGetNames_ELF ( oc ); |
| if (!r) { return r; } |
| |
| /* loaded, but not resolved yet */ |
| oc->status = OBJECT_LOADED; |
| |
| #ifdef ppc32_TARGET_ARCH |
| invalidate_icache(oc->image, oc->fileSize); |
| #endif |
| |
| return 1; |
| } |
| |
| |
| |
| /* --------------------------------------------------------------------------- |
| * resolve all the currently unlinked objects in memory |
| * |
| * Returns: 1 if ok, 0 on error. |
| */ |
| static |
| int resolveObjs( void ) |
| { |
| ObjectCode *oc; |
| int r; |
| |
| initLinker(); |
| |
| for (oc = global_object_list; oc; oc = oc->next) { |
| if (oc->status != OBJECT_RESOLVED) { |
| r = ocResolve_ELF ( oc ); |
| if (!r) { return r; } |
| oc->status = OBJECT_RESOLVED; |
| } |
| } |
| return 1; |
| } |
| |
| |
| /* --------------------------------------------------------------------------- |
| * Top-level linker. |
| */ |
| |
| /* Load and link a bunch of .o's, and return the address of |
| 'entry'. Or NULL if something borks. |
| */ |
| void* linker_top_level_LINK ( int n_object_names, char** object_names ) |
| { |
| int r, i; |
| void* mainp; |
| |
| initLinker(); |
| for (i = 0; i < n_object_names; i++) { |
| //fprintf(stderr, "linkloop %d %s\n", i, object_names[i] ); |
| r = loadObj( object_names[i] ); |
| if (r != 1) return NULL; |
| } |
| r = resolveObjs(); |
| if (r != 1) return NULL; |
| mainp = search_StringMap ( global_symbol_table, "entry" ); |
| if (mainp == NULL) return NULL; |
| printf("switchback: Linker: success!\n"); |
| return mainp; |
| } |
| |
| |
| #endif |