20 #include "pthread_impl.h"
24 static void error(const char *, ...);
28 #define MAXP2(a,b) (-(-(a)&-(b)))
29 #define ALIGN(x,y) ((x)+(y)-1 & -(y))
41 struct td_index *next;
48 struct dso *next, *prev;
67 struct dso **deps, *needed_by;
68 char *rpath_orig, *rpath;
70 size_t tls_len, tls_size, tls_align, tls_id, tls_offset;
71 size_t relro_start, relro_end;
73 unsigned char *new_tls;
74 volatile int new_dtv_idx, new_tls_idx;
75 struct td_index *td_index;
76 struct dso *fini_next;
77 int rel_early_relative, rel_update_got;
87 int __init_tp(void *);
88 void __init_libc(char **, char *);
90 const char *__libc_get_version(void);
92 static struct builtin_tls {
97 #define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)
99 static struct dso ldso;
100 static struct dso *head, *tail, *fini_head;
101 static char *env_path, *sys_path;
102 static unsigned long long gencnt;
105 static int ldso_fail;
107 static jmp_buf *rtld_fail;
108 static pthread_rwlock_t lock;
109 static struct debug debug;
110 static size_t tls_cnt, tls_offset, tls_align = MIN_TLS_ALIGN;
111 static size_t static_tls_cnt;
112 static pthread_mutex_t init_fini_lock = { ._m_type = PTHREAD_MUTEX_RECURSIVE };
114 struct debug *_dl_debug_addr = &debug;
116 static int dl_strcmp(const char *l, const char *r)
118 for (; *l==*r && *l; l++, r++);
119 return *(unsigned char *)l - *(unsigned char *)r;
121 #define strcmp(l,r) dl_strcmp(l,r)
123 static void decode_vec(size_t *v, size_t *a, size_t cnt)
126 for (i=0; i<cnt; i++) a[i] = 0;
127 for (; v[0]; v+=2) if (v[0]-1<cnt-1) {
133 static int search_vec(size_t *v, size_t *r, size_t key)
135 for (; v[0]!=key; v+=2)
141 static uint32_t sysv_hash(const char *s0)
143 const unsigned char *s = (void *)s0;
149 return h & 0xfffffff;
152 static uint32_t gnu_hash(const char *s0)
154 const unsigned char *s = (void *)s0;
155 uint_fast32_t h = 5381;
161 static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
164 Sym *syms = dso->syms;
165 uint32_t *hashtab = dso->hashtab;
166 char *strings = dso->strings;
167 for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {
168 if ((!dso->versym || dso->versym[i] >= 0)
169 && (!strcmp(s, strings+syms[i].st_name)))
175 static Sym *gnu_lookup(const char *s, uint32_t h1, struct dso *dso)
177 Sym *syms = dso->syms;
178 char *strings = dso->strings;
179 uint32_t *hashtab = dso->ghashtab;
180 uint32_t nbuckets = hashtab[0];
181 uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
184 uint32_t i = buckets[h1 % nbuckets];
188 hashval = buckets + nbuckets + (i - hashtab[1]);
190 for (h1 |= 1; ; i++) {
192 if ((!dso->versym || dso->versym[i] >= 0)
193 && (h1 == (h2|1)) && !strcmp(s, strings + syms[i].st_name))
201 #define OK_TYPES (1<<STT_NOTYPE | 1<<STT_OBJECT | 1<<STT_FUNC | 1<<STT_COMMON | 1<<STT_TLS)
202 #define OK_BINDS (1<<STB_GLOBAL | 1<<STB_WEAK | 1<<STB_GNU_UNIQUE)
204 #ifndef ARCH_SYM_REJECT_UND
205 #define ARCH_SYM_REJECT_UND(s) 0
208 static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
210 uint32_t h = 0, gh = 0;
211 struct symdef def = {0};
212 for (; dso; dso=dso->next) {
214 if (!dso->global) continue;
216 if (!gh) gh = gnu_hash(s);
217 sym = gnu_lookup(s, gh, dso);
219 if (!h) h = sysv_hash(s);
220 sym = sysv_lookup(s, h, dso);
224 if (need_def || (sym->st_info&0xf) == STT_TLS
225 || ARCH_SYM_REJECT_UND(sym))
228 if ((sym->st_info&0xf) != STT_TLS)
230 if (!(1<<(sym->st_info&0xf) & OK_TYPES)) continue;
231 if (!(1<<(sym->st_info>>4) & OK_BINDS)) continue;
233 if (def.sym && sym->st_info>>4 == STB_WEAK) continue;
236 if (sym->st_info>>4 == STB_GLOBAL) break;
241 __attribute__((__visibility__("hidden")))
242 ptrdiff_t __tlsdesc_static(), __tlsdesc_dynamic();
244 static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stride)
246 unsigned char *base = dso->base;
247 Sym *syms = dso->syms;
248 char *strings = dso->strings;
260 for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {
261 if (dso->rel_early_relative && IS_RELATIVE(rel[1])) continue;
262 type = R_TYPE(rel[1]);
263 sym_index = R_SYM(rel[1]);
264 reloc_addr = (void *)(base + rel[0]);
266 sym = syms + sym_index;
267 name = strings + sym->st_name;
268 ctx = type==REL_COPY ? head->next : head;
269 def = find_sym(ctx, name, type==REL_PLT);
270 if (!def.sym && (sym->st_shndx != SHN_UNDEF
271 || sym->st_info>>4 != STB_WEAK)) {
272 error("Error relocating %s: %s: symbol not found",
274 if (runtime) longjmp(*rtld_fail, 1);
283 int gotplt = (type == REL_GOT || type == REL_PLT);
284 if (dso->rel_update_got && !gotplt && stride==2) continue;
286 addend = stride>2 ? rel[2]
287 : gotplt || type==REL_COPY ? 0
290 sym_val = def.sym ? (size_t)def.dso->base+def.sym->st_value : 0;
291 tls_val = def.sym ? def.sym->st_value : 0;
297 addend -= (size_t)reloc_addr;
301 *reloc_addr = sym_val + addend;
304 *reloc_addr = (size_t)base + addend;
307 if (sym) *reloc_addr = sym_val + addend;
308 else *reloc_addr = (size_t)base + addend;
311 memcpy(reloc_addr, (void *)sym_val, sym->st_size);
314 *(uint32_t *)reloc_addr = sym_val + addend
315 - (size_t)reloc_addr;
318 *reloc_addr = def.dso->tls_id;
321 *reloc_addr = tls_val + addend;
325 *reloc_addr = tls_val + def.dso->tls_offset + TPOFF_K + addend;
329 *reloc_addr = tls_val - def.dso->tls_offset + addend;
332 *reloc_addr = def.dso->tls_offset - tls_val + addend;
336 if (stride<3) addend = reloc_addr[1];
337 if (runtime && def.dso->tls_id >= static_tls_cnt) {
338 struct td_index *new = malloc(sizeof *new);
341 "Error relocating %s: cannot allocate TLSDESC for %s",
342 dso->name, sym ? name : "(local)" );
343 longjmp(*rtld_fail, 1);
345 new->next = dso->td_index;
347 new->args[0] = def.dso->tls_id;
348 new->args[1] = tls_val + addend;
349 reloc_addr[0] = (size_t)__tlsdesc_dynamic;
350 reloc_addr[1] = (size_t)new;
352 reloc_addr[0] = (size_t)__tlsdesc_static;
354 reloc_addr[1] = tls_val + def.dso->tls_offset
357 reloc_addr[1] = tls_val - def.dso->tls_offset
363 error("Error relocating %s: unsupported relocation type %d",
365 if (runtime) longjmp(*rtld_fail, 1);
371 /* A huge hack: to make up for the wastefulness of shared libraries
372 * needing at least a page of dirty memory even if they have no global
373 * data, we reclaim the gaps at the beginning and end of writable maps
374 * and "donate" them to the heap by setting up minimal malloc
375 * structures and then freeing them. */
377 static void reclaim(struct dso *dso, size_t start, size_t end)
380 if (start >= dso->relro_start && start < dso->relro_end) start = dso->relro_end;
381 if (end >= dso->relro_start && end < dso->relro_end) end = dso->relro_start;
382 start = start + 6*sizeof(size_t)-1 & -4*sizeof(size_t);
383 end = (end & -4*sizeof(size_t)) - 2*sizeof(size_t);
384 if (start>end || end-start < 4*sizeof(size_t)) return;
385 a = (size_t *)(dso->base + start);
386 z = (size_t *)(dso->base + end);
388 a[-1] = z[0] = end-start + 2*sizeof(size_t) | 1;
393 static void reclaim_gaps(struct dso *dso)
395 Phdr *ph = dso->phdr;
396 size_t phcnt = dso->phnum;
398 for (; phcnt--; ph=(void *)((char *)ph+dso->phentsize)) {
399 if (ph->p_type!=PT_LOAD) continue;
400 if ((ph->p_flags&(PF_R|PF_W))!=(PF_R|PF_W)) continue;
401 reclaim(dso, ph->p_vaddr & -PAGE_SIZE, ph->p_vaddr);
402 reclaim(dso, ph->p_vaddr+ph->p_memsz,
403 ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE);
407 static void *map_library(int fd, struct dso *dso)
409 Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
410 void *allocated_buf=0;
412 size_t addr_min=SIZE_MAX, addr_max=0, map_len;
413 size_t this_min, this_max;
418 unsigned char *map=MAP_FAILED, *base;
423 ssize_t l = read(fd, buf, sizeof buf);
426 if (l<sizeof *eh || (eh->e_type != ET_DYN && eh->e_type != ET_EXEC))
428 phsize = eh->e_phentsize * eh->e_phnum;
429 if (phsize > sizeof buf - sizeof *eh) {
430 allocated_buf = malloc(phsize);
431 if (!allocated_buf) return 0;
432 l = pread(fd, allocated_buf, phsize, eh->e_phoff);
433 if (l < 0) goto error;
434 if (l != phsize) goto noexec;
435 ph = ph0 = allocated_buf;
436 } else if (eh->e_phoff + phsize > l) {
437 l = pread(fd, buf+1, phsize, eh->e_phoff);
438 if (l < 0) goto error;
439 if (l != phsize) goto noexec;
440 ph = ph0 = (void *)(buf + 1);
442 ph = ph0 = (void *)((char *)buf + eh->e_phoff);
444 for (i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
445 if (ph->p_type == PT_DYNAMIC) {
447 } else if (ph->p_type == PT_TLS) {
448 tls_image = ph->p_vaddr;
449 dso->tls_align = ph->p_align;
450 dso->tls_len = ph->p_filesz;
451 dso->tls_size = ph->p_memsz;
452 } else if (ph->p_type == PT_GNU_RELRO) {
453 dso->relro_start = ph->p_vaddr & -PAGE_SIZE;
454 dso->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
456 if (ph->p_type != PT_LOAD) continue;
457 if (ph->p_vaddr < addr_min) {
458 addr_min = ph->p_vaddr;
459 off_start = ph->p_offset;
460 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
461 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
462 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
464 if (ph->p_vaddr+ph->p_memsz > addr_max) {
465 addr_max = ph->p_vaddr+ph->p_memsz;
468 if (!dyn) goto noexec;
469 addr_max += PAGE_SIZE-1;
470 addr_max &= -PAGE_SIZE;
471 addr_min &= -PAGE_SIZE;
472 off_start &= -PAGE_SIZE;
473 map_len = addr_max - addr_min + off_start;
474 /* The first time, we map too much, possibly even more than
475 * the length of the file. This is okay because we will not
476 * use the invalid part; we just need to reserve the right
477 * amount of virtual address space to map over later. */
478 map = mmap((void *)addr_min, map_len, prot, MAP_PRIVATE, fd, off_start);
479 if (map==MAP_FAILED) goto error;
480 /* If the loaded file is not relocatable and the requested address is
481 * not available, then the load operation must fail. */
482 if (eh->e_type != ET_DYN && addr_min && map!=(void *)addr_min) {
486 base = map - addr_min;
489 for (ph=ph0, i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
490 if (ph->p_type != PT_LOAD) continue;
491 /* Check if the programs headers are in this load segment, and
492 * if so, record the address for use by dl_iterate_phdr. */
493 if (!dso->phdr && eh->e_phoff >= ph->p_offset
494 && eh->e_phoff+phsize <= ph->p_offset+ph->p_filesz) {
495 dso->phdr = (void *)(base + ph->p_vaddr
496 + (eh->e_phoff-ph->p_offset));
497 dso->phnum = eh->e_phnum;
498 dso->phentsize = eh->e_phentsize;
500 /* Reuse the existing mapping for the lowest-address LOAD */
501 if ((ph->p_vaddr & -PAGE_SIZE) == addr_min) continue;
502 this_min = ph->p_vaddr & -PAGE_SIZE;
503 this_max = ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE;
504 off_start = ph->p_offset & -PAGE_SIZE;
505 prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
506 ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
507 ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
508 if (mmap(base+this_min, this_max-this_min, prot, MAP_PRIVATE|MAP_FIXED, fd, off_start) == MAP_FAILED)
510 if (ph->p_memsz > ph->p_filesz) {
511 size_t brk = (size_t)base+ph->p_vaddr+ph->p_filesz;
512 size_t pgbrk = brk+PAGE_SIZE-1 & -PAGE_SIZE;
513 memset((void *)brk, 0, pgbrk-brk & PAGE_SIZE-1);
514 if (pgbrk-(size_t)base < this_max && mmap((void *)pgbrk, (size_t)base+this_max-pgbrk, prot, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) == MAP_FAILED)
518 for (i=0; ((size_t *)(base+dyn))[i]; i+=2)
519 if (((size_t *)(base+dyn))[i]==DT_TEXTREL) {
520 if (mprotect(map, map_len, PROT_READ|PROT_WRITE|PROT_EXEC) < 0)
525 dso->map_len = map_len;
527 dso->dynv = (void *)(base+dyn);
528 if (dso->tls_size) dso->tls_image = (void *)(base+tls_image);
529 if (!runtime) reclaim_gaps(dso);
535 if (map!=MAP_FAILED) munmap(map, map_len);
540 static int path_open(const char *name, const char *s, char *buf, size_t buf_size)
545 s += strspn(s, ":\n");
546 l = strcspn(s, ":\n");
547 if (l-1 >= INT_MAX) return -1;
548 if (snprintf(buf, buf_size, "%.*s/%s", (int)l, s, name) < buf_size) {
549 if ((fd = open(buf, O_RDONLY|O_CLOEXEC))>=0) return fd;
557 /* Any negative value but -1 will inhibit
558 * futher path search. */
566 static int fixup_rpath(struct dso *p, char *buf, size_t buf_size)
569 const char *s, *t, *origin;
571 if (p->rpath || !p->rpath_orig) return 0;
572 if (!strchr(p->rpath_orig, '$')) {
573 p->rpath = p->rpath_orig;
578 while ((t=strchr(s, '$'))) {
579 if (strncmp(t, "$ORIGIN", 7) && strncmp(t, "${ORIGIN}", 9))
584 if (n > SSIZE_MAX/PATH_MAX) return 0;
586 if (p->kernel_mapped) {
587 /* $ORIGIN searches cannot be performed for the main program
588 * when it is suid/sgid/AT_SECURE. This is because the
589 * pathname is under the control of the caller of execve.
590 * For libraries, however, $ORIGIN can be processed safely
591 * since the library's pathname came from a trusted source
592 * (either system paths or a call to dlopen). */
595 l = readlink("/proc/self/exe", buf, buf_size);
596 if (l == -1) switch (errno) {
611 t = strrchr(origin, '/');
612 l = t ? t-origin : 0;
613 p->rpath = malloc(strlen(p->rpath_orig) + n*l + 1);
614 if (!p->rpath) return -1;
618 while ((t=strchr(s, '$'))) {
621 memcpy(d, origin, l);
623 /* It was determined previously that the '$' is followed
624 * either by "ORIGIN" or "{ORIGIN}". */
625 s = t + 7 + 2*(t[1]=='{');
631 static void decode_dyn(struct dso *p)
634 decode_vec(p->dynv, dyn, DYN_CNT);
635 p->syms = (void *)(p->base + dyn[DT_SYMTAB]);
636 p->strings = (void *)(p->base + dyn[DT_STRTAB]);
637 if (dyn[0]&(1<<DT_HASH))
638 p->hashtab = (void *)(p->base + dyn[DT_HASH]);
639 if (dyn[0]&(1<<DT_RPATH))
640 p->rpath_orig = (void *)(p->strings + dyn[DT_RPATH]);
641 if (dyn[0]&(1<<DT_RUNPATH))
642 p->rpath_orig = (void *)(p->strings + dyn[DT_RUNPATH]);
643 if (search_vec(p->dynv, dyn, DT_GNU_HASH))
644 p->ghashtab = (void *)(p->base + *dyn);
645 if (search_vec(p->dynv, dyn, DT_VERSYM))
646 p->versym = (void *)(p->base + *dyn);
649 static struct dso *load_library(const char *name, struct dso *needed_by)
651 char buf[2*NAME_MAX+2];
652 const char *pathname;
654 struct dso *p, temp_dso = {0};
666 /* Catch and block attempts to reload the implementation itself */
667 if (name[0]=='l' && name[1]=='i' && name[2]=='b') {
668 static const char *rp, reserved[] =
669 "c\0pthread\0rt\0m\0dl\0util\0xnet\0";
670 char *z = strchr(name, '.');
673 for (rp=reserved; *rp && strncmp(name+3, rp, l-3); rp+=strlen(rp)+1);
676 /* Track which names have been resolved
677 * and only report each one once. */
678 static unsigned reported;
679 unsigned mask = 1U<<(rp-reserved);
680 if (!(reported & mask)) {
682 dprintf(1, "\t%s => %s (%p)\n",
691 if (!strcmp(name, ldso.name)) is_self = 1;
696 tail = ldso.next ? ldso.next : &ldso;
700 if (strchr(name, '/')) {
702 fd = open(name, O_RDONLY|O_CLOEXEC);
704 /* Search for the name to see if it's already loaded */
705 for (p=head->next; p; p=p->next) {
706 if (p->shortname && !strcmp(p->shortname, name)) {
711 if (strlen(name) > NAME_MAX) return 0;
713 if (env_path) fd = path_open(name, env_path, buf, sizeof buf);
714 for (p=needed_by; fd == -1 && p; p=p->needed_by) {
715 if (fixup_rpath(p, buf, sizeof buf) < 0)
716 fd = -2; /* Inhibit further search. */
718 fd = path_open(name, p->rpath, buf, sizeof buf);
724 if (ldso.name[0]=='/') {
726 for (s=t=z=ldso.name; *s; s++)
727 if (*s=='/') z=t, t=s;
728 prefix_len = z-ldso.name;
729 if (prefix_len < PATH_MAX)
736 char etc_ldso_path[prefix_len + 1
737 + sizeof "/etc/ld-musl-" LDSO_ARCH ".path"];
738 snprintf(etc_ldso_path, sizeof etc_ldso_path,
739 "%.*s/etc/ld-musl-" LDSO_ARCH ".path",
740 (int)prefix_len, prefix);
741 FILE *f = fopen(etc_ldso_path, "rbe");
743 if (getdelim(&sys_path, (size_t[1]){0}, 0, f) <= 0) {
748 } else if (errno != ENOENT) {
752 if (!sys_path) sys_path = "/lib:/usr/local/lib:/usr/lib";
753 fd = path_open(name, sys_path, buf, sizeof buf);
757 if (fd < 0) return 0;
758 if (fstat(fd, &st) < 0) {
762 for (p=head->next; p; p=p->next) {
763 if (p->dev == st.st_dev && p->ino == st.st_ino) {
764 /* If this library was previously loaded with a
765 * pathname but a search found the same inode,
766 * setup its shortname so it can be found by name. */
767 if (!p->shortname && pathname != name)
768 p->shortname = strrchr(p->name, '/')+1;
774 map = noload ? 0 : map_library(fd, &temp_dso);
778 /* Allocate storage for the new DSO. When there is TLS, this
779 * storage must include a reservation for all pre-existing
780 * threads to obtain copies of both the new TLS, and an
781 * extended DTV capable of storing an additional slot for
782 * the newly-loaded DSO. */
783 alloc_size = sizeof *p + strlen(pathname) + 1;
784 if (runtime && temp_dso.tls_image) {
785 size_t per_th = temp_dso.tls_size + temp_dso.tls_align
786 + sizeof(void *) * (tls_cnt+3);
787 n_th = libc.threads_minus_1 + 1;
788 if (n_th > SSIZE_MAX / per_th) alloc_size = SIZE_MAX;
789 else alloc_size += n_th * per_th;
791 p = calloc(1, alloc_size);
793 munmap(map, temp_dso.map_len);
796 memcpy(p, &temp_dso, sizeof temp_dso);
801 p->needed_by = needed_by;
803 strcpy(p->name, pathname);
804 /* Add a shortname only if name arg was not an explicit pathname. */
805 if (pathname != name) p->shortname = strrchr(p->name, '/')+1;
807 p->tls_id = ++tls_cnt;
808 tls_align = MAXP2(tls_align, p->tls_align);
810 p->tls_offset = tls_offset + ( (tls_align-1) &
811 -(tls_offset + (uintptr_t)p->tls_image) );
812 tls_offset += p->tls_size;
814 tls_offset += p->tls_size + p->tls_align - 1;
815 tls_offset -= (tls_offset + (uintptr_t)p->tls_image)
817 p->tls_offset = tls_offset;
819 p->new_dtv = (void *)(-sizeof(size_t) &
820 (uintptr_t)(p->name+strlen(p->name)+sizeof(size_t)));
821 p->new_tls = (void *)(p->new_dtv + n_th*(tls_cnt+1));
828 if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);
833 static void load_deps(struct dso *p)
836 struct dso ***deps = &p->deps, **tmp, *dep;
837 for (; p; p=p->next) {
838 for (i=0; p->dynv[i]; i+=2) {
839 if (p->dynv[i] != DT_NEEDED) continue;
840 dep = load_library(p->strings + p->dynv[i+1], p);
842 error("Error loading shared library %s: %m (needed by %s)",
843 p->strings + p->dynv[i+1], p->name);
844 if (runtime) longjmp(*rtld_fail, 1);
848 tmp = realloc(*deps, sizeof(*tmp)*(ndeps+2));
849 if (!tmp) longjmp(*rtld_fail, 1);
858 static void load_preload(char *s)
863 for ( ; *s && (isspace(*s) || *s==':'); s++);
864 for (z=s; *z && !isspace(*z) && *z!=':'; z++);
872 static void make_global(struct dso *p)
874 for (; p; p=p->next) p->global = 1;
877 static void do_mips_relocs(struct dso *p, size_t *got)
880 unsigned char *base = p->base;
881 i=0; search_vec(p->dynv, &i, DT_MIPS_LOCAL_GOTNO);
882 if (p->rel_early_relative) {
885 while (i--) *got++ += (size_t)base;
887 j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
888 i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
889 Sym *sym = p->syms + j;
890 rel[0] = (unsigned char *)got - base;
891 for (i-=j; i; i--, sym++, rel[0]+=sizeof(size_t)) {
892 rel[1] = sym-p->syms << 8 | R_MIPS_JUMP_SLOT;
893 do_relocs(p, rel, sizeof rel, 2);
897 static void reloc_all(struct dso *p)
900 for (; p; p=p->next) {
901 if (p->relocated) continue;
902 decode_vec(p->dynv, dyn, DYN_CNT);
903 if (NEED_MIPS_GOT_RELOCS)
904 do_mips_relocs(p, (void *)(p->base+dyn[DT_PLTGOT]));
905 do_relocs(p, (void *)(p->base+dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
906 2+(dyn[DT_PLTREL]==DT_RELA));
907 do_relocs(p, (void *)(p->base+dyn[DT_REL]), dyn[DT_RELSZ], 2);
908 do_relocs(p, (void *)(p->base+dyn[DT_RELA]), dyn[DT_RELASZ], 3);
910 if (head != &ldso && p->relro_start != p->relro_end &&
911 mprotect(p->base+p->relro_start, p->relro_end-p->relro_start, PROT_READ) < 0) {
912 error("Error relocating %s: RELRO protection failed: %m",
914 if (runtime) longjmp(*rtld_fail, 1);
921 static void kernel_mapped_dso(struct dso *p)
923 size_t min_addr = -1, max_addr = 0, cnt;
925 for (cnt = p->phnum; cnt--; ph = (void *)((char *)ph + p->phentsize)) {
926 if (ph->p_type == PT_DYNAMIC) {
927 p->dynv = (void *)(p->base + ph->p_vaddr);
928 } else if (ph->p_type == PT_GNU_RELRO) {
929 p->relro_start = ph->p_vaddr & -PAGE_SIZE;
930 p->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
932 if (ph->p_type != PT_LOAD) continue;
933 if (ph->p_vaddr < min_addr)
934 min_addr = ph->p_vaddr;
935 if (ph->p_vaddr+ph->p_memsz > max_addr)
936 max_addr = ph->p_vaddr+ph->p_memsz;
938 min_addr &= -PAGE_SIZE;
939 max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE;
940 p->map = p->base + min_addr;
941 p->map_len = max_addr - min_addr;
942 p->kernel_mapped = 1;
945 static void do_fini()
949 for (p=fini_head; p; p=p->fini_next) {
950 if (!p->constructed) continue;
951 decode_vec(p->dynv, dyn, DYN_CNT);
952 if (dyn[0] & (1<<DT_FINI_ARRAY)) {
953 size_t n = dyn[DT_FINI_ARRAYSZ]/sizeof(size_t);
954 size_t *fn = (size_t *)(p->base + dyn[DT_FINI_ARRAY])+n;
955 while (n--) ((void (*)(void))*--fn)();
957 #ifndef NO_LEGACY_INITFINI
958 if ((dyn[0] & (1<<DT_FINI)) && dyn[DT_FINI])
959 ((void (*)(void))(p->base + dyn[DT_FINI]))();
964 static void do_init_fini(struct dso *p)
967 int need_locking = libc.threads_minus_1;
968 /* Allow recursive calls that arise when a library calls
969 * dlopen from one of its constructors, but block any
970 * other threads until all ctors have finished. */
971 if (need_locking) pthread_mutex_lock(&init_fini_lock);
972 for (; p; p=p->prev) {
973 if (p->constructed) continue;
975 decode_vec(p->dynv, dyn, DYN_CNT);
976 if (dyn[0] & ((1<<DT_FINI) | (1<<DT_FINI_ARRAY))) {
977 p->fini_next = fini_head;
980 #ifndef NO_LEGACY_INITFINI
981 if ((dyn[0] & (1<<DT_INIT)) && dyn[DT_INIT])
982 ((void (*)(void))(p->base + dyn[DT_INIT]))();
984 if (dyn[0] & (1<<DT_INIT_ARRAY)) {
985 size_t n = dyn[DT_INIT_ARRAYSZ]/sizeof(size_t);
986 size_t *fn = (void *)(p->base + dyn[DT_INIT_ARRAY]);
987 while (n--) ((void (*)(void))*fn++)();
989 if (!need_locking && libc.threads_minus_1) {
991 pthread_mutex_lock(&init_fini_lock);
994 if (need_locking) pthread_mutex_unlock(&init_fini_lock);
997 static void dl_debug_state(void)
1001 weak_alias(dl_debug_state, _dl_debug_state);
1005 pthread_t self = __pthread_self();
1007 for (p=head; p; p=p->next) {
1008 if (!p->tls_id || !self->dtv[p->tls_id]) continue;
1009 memcpy(self->dtv[p->tls_id], p->tls_image, p->tls_len);
1010 memset((char *)self->dtv[p->tls_id]+p->tls_len, 0,
1011 p->tls_size - p->tls_len);
1012 if (p->tls_id == (size_t)self->dtv[0]) break;
1016 void *__copy_tls(unsigned char *mem)
1023 dtv = (void **)(mem + libc.tls_size) - (tls_cnt + 1);
1025 mem += -((uintptr_t)mem + sizeof(struct pthread)) & (tls_align-1);
1026 td = (pthread_t)mem;
1027 mem += sizeof(struct pthread);
1029 for (p=head; p; p=p->next) {
1030 if (!p->tls_id) continue;
1031 dtv[p->tls_id] = mem + p->tls_offset;
1032 memcpy(dtv[p->tls_id], p->tls_image, p->tls_len);
1037 mem += libc.tls_size - sizeof(struct pthread);
1038 mem -= (uintptr_t)mem & (tls_align-1);
1039 td = (pthread_t)mem;
1041 for (p=head; p; p=p->next) {
1042 if (!p->tls_id) continue;
1043 dtv[p->tls_id] = mem - p->tls_offset;
1044 memcpy(dtv[p->tls_id], p->tls_image, p->tls_len);
1047 dtv[0] = (void *)tls_cnt;
1048 td->dtv = td->dtv_copy = dtv;
1052 __attribute__((__visibility__("hidden")))
1053 void *__tls_get_new(size_t *v)
1055 pthread_t self = __pthread_self();
1057 /* Block signals to make accessing new TLS async-signal-safe */
1059 __block_all_sigs(&set);
1060 if (v[0]<=(size_t)self->dtv[0]) {
1061 __restore_sigs(&set);
1062 return (char *)self->dtv[v[0]]+v[1];
1065 /* This is safe without any locks held because, if the caller
1066 * is able to request the Nth entry of the DTV, the DSO list
1067 * must be valid at least that far out and it was synchronized
1068 * at program startup or by an already-completed call to dlopen. */
1070 for (p=head; p->tls_id != v[0]; p=p->next);
1072 /* Get new DTV space from new DSO if needed */
1073 if (v[0] > (size_t)self->dtv[0]) {
1074 void **newdtv = p->new_dtv +
1075 (v[0]+1)*sizeof(void *)*a_fetch_add(&p->new_dtv_idx,1);
1076 memcpy(newdtv, self->dtv,
1077 ((size_t)self->dtv[0]+1) * sizeof(void *));
1078 newdtv[0] = (void *)v[0];
1079 self->dtv = self->dtv_copy = newdtv;
1082 /* Get new TLS memory from all new DSOs up to the requested one */
1084 for (p=head; ; p=p->next) {
1085 if (!p->tls_id || self->dtv[p->tls_id]) continue;
1086 mem = p->new_tls + (p->tls_size + p->tls_align)
1087 * a_fetch_add(&p->new_tls_idx,1);
1088 mem += ((uintptr_t)p->tls_image - (uintptr_t)mem)
1090 self->dtv[p->tls_id] = mem;
1091 memcpy(mem, p->tls_image, p->tls_len);
1092 if (p->tls_id == v[0]) break;
1094 __restore_sigs(&set);
1098 static void update_tls_size()
1100 libc.tls_size = ALIGN(
1101 (1+tls_cnt) * sizeof(void *) +
1103 sizeof(struct pthread) +
1108 /* Stage 1 of the dynamic linker is defined in dlstart.c. It calls the
1109 * following stage 2 and stage 3 functions via primitive symbolic lookup
1110 * since it does not have access to their addresses to begin with. */
1112 /* Stage 2 of the dynamic linker is called after relative relocations
1113 * have been processed. It can make function calls to static functions
1114 * and access string literals and static data, but cannot use extern
1115 * symbols. Its job is to perform symbolic relocations on the dynamic
1116 * linker itself, but some of the relocations performed may need to be
1117 * replaced later due to copy relocations in the main program. */
1119 void __dls2(unsigned char *base, size_t *sp)
1121 Ehdr *ehdr = (void *)base;
1123 ldso.name = ldso.shortname = "libc.so";
1125 ldso.phnum = ehdr->e_phnum;
1126 ldso.phdr = (void *)(base + ehdr->e_phoff);
1127 ldso.phentsize = ehdr->e_phentsize;
1128 ldso.rel_early_relative = 1;
1129 kernel_mapped_dso(&ldso);
1136 ldso.rel_update_got = 1;
1138 /* Call dynamic linker stage-3, __dls3, looking it up
1139 * symbolically as a barrier against moving the address
1140 * load across the above relocation processing. */
1141 struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);
1142 ((stage3_func)(ldso.base+dls3_def.sym->st_value))(sp);
1145 /* Stage 3 of the dynamic linker is called with the dynamic linker/libc
1146 * fully functional. Its job is to load (if not already loaded) and
1147 * process dependencies and relocations for the main application and
1148 * transfer control to its entry point. */
1150 _Noreturn void __dls3(size_t *sp)
1152 static struct dso app, vdso;
1153 size_t aux[AUX_CNT], *auxv;
1155 char *env_preload=0;
1158 char **argv = (void *)(sp+1);
1159 char **argv_orig = argv;
1160 char **envp = argv+argc+1;
1162 /* Setup early thread pointer in builtin_tls for ldso/libc itself to
1163 * use during dynamic linking. If possible it will also serve as the
1164 * thread pointer at runtime. */
1165 libc.tls_size = sizeof builtin_tls;
1166 if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
1170 /* Find aux vector just past environ[] */
1171 for (i=argc+1; argv[i]; i++)
1172 if (!memcmp(argv[i], "LD_LIBRARY_PATH=", 16))
1173 env_path = argv[i]+16;
1174 else if (!memcmp(argv[i], "LD_PRELOAD=", 11))
1175 env_preload = argv[i]+11;
1176 auxv = (void *)(argv+i+1);
1178 decode_vec(auxv, aux, AUX_CNT);
1180 /* Only trust user/env if kernel says we're not suid/sgid */
1181 if ((aux[0]&0x7800)!=0x7800 || aux[AT_UID]!=aux[AT_EUID]
1182 || aux[AT_GID]!=aux[AT_EGID] || aux[AT_SECURE]) {
1187 libc.page_size = aux[AT_PAGESZ];
1190 /* If the main program was already loaded by the kernel,
1191 * AT_PHDR will point to some location other than the dynamic
1192 * linker's program headers. */
1193 if (aux[AT_PHDR] != (size_t)ldso.phdr) {
1194 size_t interp_off = 0;
1195 size_t tls_image = 0;
1196 /* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
1197 Phdr *phdr = app.phdr = (void *)aux[AT_PHDR];
1198 app.phnum = aux[AT_PHNUM];
1199 app.phentsize = aux[AT_PHENT];
1200 for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
1201 if (phdr->p_type == PT_PHDR)
1202 app.base = (void *)(aux[AT_PHDR] - phdr->p_vaddr);
1203 else if (phdr->p_type == PT_INTERP)
1204 interp_off = (size_t)phdr->p_vaddr;
1205 else if (phdr->p_type == PT_TLS) {
1206 tls_image = phdr->p_vaddr;
1207 app.tls_len = phdr->p_filesz;
1208 app.tls_size = phdr->p_memsz;
1209 app.tls_align = phdr->p_align;
1212 if (app.tls_size) app.tls_image = (char *)app.base + tls_image;
1213 if (interp_off) ldso.name = (char *)app.base + interp_off;
1214 if ((aux[0] & (1UL<<AT_EXECFN))
1215 && strncmp((char *)aux[AT_EXECFN], "/proc/", 6))
1216 app.name = (char *)aux[AT_EXECFN];
1219 kernel_mapped_dso(&app);
1222 char *ldname = argv[0];
1223 size_t l = strlen(ldname);
1224 if (l >= 3 && !strcmp(ldname+l-3, "ldd")) ldd_mode = 1;
1226 while (argv[0] && argv[0][0]=='-' && argv[0][1]=='-') {
1227 char *opt = argv[0]+2;
1228 *argv++ = (void *)-1;
1231 } else if (!memcmp(opt, "list", 5)) {
1233 } else if (!memcmp(opt, "library-path", 12)) {
1234 if (opt[12]=='=') env_path = opt+13;
1235 else if (opt[12]) *argv = 0;
1236 else if (*argv) env_path = *argv++;
1237 } else if (!memcmp(opt, "preload", 7)) {
1238 if (opt[7]=='=') env_preload = opt+8;
1239 else if (opt[7]) *argv = 0;
1240 else if (*argv) env_preload = *argv++;
1245 argv[-1] = (void *)(argc - (argv-argv_orig));
1247 dprintf(2, "musl libc\n"
1249 "Dynamic Program Loader\n"
1250 "Usage: %s [options] [--] pathname%s\n",
1251 __libc_get_version(), ldname,
1252 ldd_mode ? "" : " [args]");
1255 fd = open(argv[0], O_RDONLY);
1257 dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));
1261 Ehdr *ehdr = (void *)map_library(fd, &app);
1263 dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
1270 aux[AT_ENTRY] = (size_t)app.base + ehdr->e_entry;
1271 /* Find the name that would have been used for the dynamic
1272 * linker had ldd not taken its place. */
1274 for (i=0; i<app.phnum; i++) {
1275 if (app.phdr[i].p_type == PT_INTERP)
1276 ldso.name = (void *)(app.base
1277 + app.phdr[i].p_vaddr);
1279 dprintf(1, "\t%s (%p)\n", ldso.name, ldso.base);
1283 app.tls_id = tls_cnt = 1;
1286 tls_offset = app.tls_size
1287 + ( -((uintptr_t)app.tls_image + app.tls_size)
1288 & (app.tls_align-1) );
1290 tls_offset = app.tls_offset = app.tls_size
1291 + ( -((uintptr_t)app.tls_image + app.tls_size)
1292 & (app.tls_align-1) );
1294 tls_align = MAXP2(tls_align, app.tls_align);
1299 /* Attach to vdso, if provided by the kernel */
1300 if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR)) {
1301 Ehdr *ehdr = (void *)vdso_base;
1302 Phdr *phdr = vdso.phdr = (void *)(vdso_base + ehdr->e_phoff);
1303 vdso.phnum = ehdr->e_phnum;
1304 vdso.phentsize = ehdr->e_phentsize;
1305 for (i=ehdr->e_phnum; i; i--, phdr=(void *)((char *)phdr + ehdr->e_phentsize)) {
1306 if (phdr->p_type == PT_DYNAMIC)
1307 vdso.dynv = (void *)(vdso_base + phdr->p_offset);
1308 if (phdr->p_type == PT_LOAD)
1309 vdso.base = (void *)(vdso_base - phdr->p_vaddr + phdr->p_offset);
1312 vdso.shortname = "linux-gate.so.1";
1320 /* Initial dso chain consists only of the app. */
1323 /* Donate unused parts of app and library mapping to malloc */
1325 reclaim_gaps(&ldso);
1327 /* Load preload/needed libraries, add their symbols to the global
1328 * namespace, and perform all remaining relocations. */
1329 if (env_preload) load_preload(env_preload);
1333 #ifndef DYNAMIC_IS_RO
1334 for (i=0; app.dynv[i]; i+=2)
1335 if (app.dynv[i]==DT_DEBUG)
1336 app.dynv[i+1] = (size_t)&debug;
1339 /* The main program must be relocated LAST since it may contin
1340 * copy relocations which depend on libraries' relocations. */
1341 reloc_all(app.next);
1345 if (libc.tls_size > sizeof builtin_tls || tls_align > MIN_TLS_ALIGN) {
1346 void *initial_tls = calloc(libc.tls_size, 1);
1348 dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
1349 argv[0], libc.tls_size);
1352 if (__init_tp(__copy_tls(initial_tls)) < 0) {
1356 size_t tmp_tls_size = libc.tls_size;
1357 pthread_t self = __pthread_self();
1358 /* Temporarily set the tls size to the full size of
1359 * builtin_tls so that __copy_tls will use the same layout
1360 * as it did for before. Then check, just to be safe. */
1361 libc.tls_size = sizeof builtin_tls;
1362 if (__copy_tls((void*)builtin_tls) != self) a_crash();
1363 libc.tls_size = tmp_tls_size;
1365 static_tls_cnt = tls_cnt;
1367 if (ldso_fail) _exit(127);
1368 if (ldd_mode) _exit(0);
1370 /* Switch to runtime mode: any further failures in the dynamic
1371 * linker are a reportable failure rather than a fatal startup
1376 debug.bp = dl_debug_state;
1378 debug.base = ldso.base;
1382 __init_libc(envp, argv[0]);
1387 CRTJMP((void *)aux[AT_ENTRY], argv-1);
1391 void *dlopen(const char *file, int mode)
1393 struct dso *volatile p, *orig_tail, *next;
1394 size_t orig_tls_cnt, orig_tls_offset, orig_tls_align;
1399 if (!file) return head;
1401 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
1402 pthread_rwlock_wrlock(&lock);
1406 orig_tls_cnt = tls_cnt;
1407 orig_tls_offset = tls_offset;
1408 orig_tls_align = tls_align;
1410 noload = mode & RTLD_NOLOAD;
1413 if (setjmp(*rtld_fail)) {
1414 /* Clean up anything new that was (partially) loaded */
1415 if (p && p->deps) for (i=0; p->deps[i]; i++)
1416 if (p->deps[i]->global < 0)
1417 p->deps[i]->global = 0;
1418 for (p=orig_tail->next; p; p=next) {
1420 munmap(p->map, p->map_len);
1421 while (p->td_index) {
1422 void *tmp = p->td_index->next;
1426 if (p->rpath != p->rpath_orig)
1431 tls_cnt = orig_tls_cnt;
1432 tls_offset = orig_tls_offset;
1433 tls_align = orig_tls_align;
1438 } else p = load_library(file, head);
1442 "Library %s is not already loaded" :
1443 "Error loading shared library %s: %m",
1448 /* First load handling */
1451 if (p->deps) for (i=0; p->deps[i]; i++)
1452 if (!p->deps[i]->global)
1453 p->deps[i]->global = -1;
1454 if (!p->global) p->global = -1;
1456 if (p->deps) for (i=0; p->deps[i]; i++)
1457 if (p->deps[i]->global < 0)
1458 p->deps[i]->global = 0;
1459 if (p->global < 0) p->global = 0;
1462 if (mode & RTLD_GLOBAL) {
1463 if (p->deps) for (i=0; p->deps[i]; i++)
1464 p->deps[i]->global = 1;
1474 pthread_rwlock_unlock(&lock);
1475 if (p) do_init_fini(orig_tail);
1476 pthread_setcancelstate(cs, 0);
1480 static int invalid_dso_handle(void *h)
1483 for (p=head; p; p=p->next) if (h==p) return 0;
1484 error("Invalid library handle %p", (void *)h);
1488 void *__tls_get_addr(size_t *);
1490 static void *do_dlsym(struct dso *p, const char *s, void *ra)
1493 uint32_t h = 0, gh = 0;
1495 if (p == head || p == RTLD_DEFAULT || p == RTLD_NEXT) {
1496 if (p == RTLD_DEFAULT) {
1498 } else if (p == RTLD_NEXT) {
1499 for (p=head; p && (unsigned char *)ra-p->map>p->map_len; p=p->next);
1503 struct symdef def = find_sym(p, s, 0);
1504 if (!def.sym) goto failed;
1505 if ((def.sym->st_info&0xf) == STT_TLS)
1506 return __tls_get_addr((size_t []){def.dso->tls_id, def.sym->st_value});
1507 return def.dso->base + def.sym->st_value;
1509 if (invalid_dso_handle(p))
1513 sym = gnu_lookup(s, gh, p);
1516 sym = sysv_lookup(s, h, p);
1518 if (sym && (sym->st_info&0xf) == STT_TLS)
1519 return __tls_get_addr((size_t []){p->tls_id, sym->st_value});
1520 if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
1521 return p->base + sym->st_value;
1522 if (p->deps) for (i=0; p->deps[i]; i++) {
1523 if (p->deps[i]->ghashtab) {
1524 if (!gh) gh = gnu_hash(s);
1525 sym = gnu_lookup(s, gh, p->deps[i]);
1527 if (!h) h = sysv_hash(s);
1528 sym = sysv_lookup(s, h, p->deps[i]);
1530 if (sym && (sym->st_info&0xf) == STT_TLS)
1531 return __tls_get_addr((size_t []){p->deps[i]->tls_id, sym->st_value});
1532 if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
1533 return p->deps[i]->base + sym->st_value;
1536 error("Symbol not found: %s", s);
1540 int __dladdr(const void *addr, Dl_info *info)
1550 pthread_rwlock_rdlock(&lock);
1551 for (p=head; p && (unsigned char *)addr-p->map>p->map_len; p=p->next);
1552 pthread_rwlock_unlock(&lock);
1557 strings = p->strings;
1559 nsym = p->hashtab[1];
1563 buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4);
1564 sym += p->ghashtab[1];
1565 for (i = nsym = 0; i < p->ghashtab[0]; i++) {
1566 if (buckets[i] > nsym)
1570 nsym -= p->ghashtab[1];
1571 hashval = buckets + p->ghashtab[0] + nsym;
1573 while (!(*hashval++ & 1));
1577 for (; nsym; nsym--, sym++) {
1579 && (1<<(sym->st_info&0xf) & OK_TYPES)
1580 && (1<<(sym->st_info>>4) & OK_BINDS)) {
1581 void *symaddr = p->base + sym->st_value;
1582 if (symaddr > addr || symaddr < best)
1585 bestname = strings + sym->st_name;
1586 if (addr == symaddr)
1591 if (!best) return 0;
1593 info->dli_fname = p->name;
1594 info->dli_fbase = p->base;
1595 info->dli_sname = bestname;
1596 info->dli_saddr = best;
1601 __attribute__((__visibility__("hidden")))
1602 void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
1605 pthread_rwlock_rdlock(&lock);
1606 res = do_dlsym(p, s, ra);
1607 pthread_rwlock_unlock(&lock);
1611 int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void *data), void *data)
1613 struct dso *current;
1614 struct dl_phdr_info info;
1616 for(current = head; current;) {
1617 info.dlpi_addr = (uintptr_t)current->base;
1618 info.dlpi_name = current->name;
1619 info.dlpi_phdr = current->phdr;
1620 info.dlpi_phnum = current->phnum;
1621 info.dlpi_adds = gencnt;
1623 info.dlpi_tls_modid = current->tls_id;
1624 info.dlpi_tls_data = current->tls_image;
1626 ret = (callback)(&info, sizeof (info), data);
1628 if (ret != 0) break;
1630 pthread_rwlock_rdlock(&lock);
1631 current = current->next;
1632 pthread_rwlock_unlock(&lock);
1637 static int invalid_dso_handle(void *h)
1639 error("Invalid library handle %p", (void *)h);
1642 void *dlopen(const char *file, int mode)
1644 error("Dynamic loading not supported");
1647 void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
1649 error("Symbol not found: %s", s);
1652 int __dladdr (const void *addr, Dl_info *info)
1658 int __dlinfo(void *dso, int req, void *res)
1660 if (invalid_dso_handle(dso)) return -1;
1661 if (req != RTLD_DI_LINKMAP) {
1662 error("Unsupported request %d", req);
1665 *(struct link_map **)res = dso;
1671 pthread_t self = __pthread_self();
1672 if (!self->dlerror_flag) return 0;
1673 self->dlerror_flag = 0;
1674 char *s = self->dlerror_buf;
1675 if (s == (void *)-1)
1676 return "Dynamic linker failed to allocate memory for error message";
1681 int dlclose(void *p)
1683 return invalid_dso_handle(p);
1686 void __dl_thread_cleanup(void)
1688 pthread_t self = __pthread_self();
1689 if (self->dlerror_buf != (void *)-1)
1690 free(self->dlerror_buf);
1693 static void error(const char *fmt, ...)
1699 vdprintf(2, fmt, ap);
1706 pthread_t self = __pthread_self();
1707 if (self->dlerror_buf != (void *)-1)
1708 free(self->dlerror_buf);
1709 size_t len = vsnprintf(0, 0, fmt, ap);
1711 char *buf = malloc(len+1);
1714 vsnprintf(buf, len+1, fmt, ap);
1719 self->dlerror_buf = buf;
1720 self->dlerror_flag = 1;