diff options
| -rw-r--r-- | include/dlfcn.h | 10 | ||||
| -rw-r--r-- | src/ldso/dladdr.c | 9 | ||||
| -rw-r--r-- | src/ldso/dynlink.c | 86 |
3 files changed, 105 insertions, 0 deletions
diff --git a/include/dlfcn.h b/include/dlfcn.h index dea74c7d..e98c8ca6 100644 --- a/include/dlfcn.h +++ b/include/dlfcn.h @@ -18,6 +18,16 @@ char *dlerror(void); void *dlopen(const char *, int); void *dlsym(void *, const char *); +#ifdef _GNU_SOURCE +typedef struct { + const char *dli_fname; + void *dli_fbase; + const char *dli_sname; + void *dli_saddr; +} Dl_info; +int dladdr(void *, Dl_info *); +#endif + #ifdef __cplusplus } #endif diff --git a/src/ldso/dladdr.c b/src/ldso/dladdr.c new file mode 100644 index 00000000..265bb681 --- /dev/null +++ b/src/ldso/dladdr.c @@ -0,0 +1,9 @@ +#define _GNU_SOURCE +#include <dlfcn.h> + +int __dladdr(void *, Dl_info *); + +int dladdr(void *addr, Dl_info *info) +{ + return __dladdr(addr, info); +} diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c index c733dc5d..b8c26ace 100644 --- a/src/ldso/dynlink.c +++ b/src/ldso/dynlink.c @@ -1,3 +1,4 @@ +#define _GNU_SOURCE #include <stdio.h> #include <stdlib.h> #include <string.h> @@ -584,6 +585,22 @@ static size_t find_dyn(Phdr *ph, size_t cnt, size_t stride) return 0; } +static void find_map_range(Phdr *ph, size_t cnt, size_t stride, struct dso *p) +{ + size_t min_addr = -1, max_addr = 0; + for (; cnt--; ph = (void *)((char *)ph + stride)) { + if (ph->p_type != PT_LOAD) continue; + if (ph->p_vaddr < min_addr) + min_addr = ph->p_vaddr; + if (ph->p_vaddr+ph->p_memsz > max_addr) + max_addr = ph->p_vaddr+ph->p_memsz; + } + min_addr &= -PAGE_SIZE; + max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE; + p->map = p->base + min_addr; + p->map_len = max_addr - min_addr; +} + static void do_init_fini(struct dso *p) { size_t dyn[DYN_CNT] = {0}; @@ -647,6 +664,8 @@ void *__dynlink(int argc, char **argv) lib->name = lib->shortname = "libc.so"; lib->global = 1; ehdr = (void *)lib->base; + find_map_range((void *)(aux[AT_BASE]+ehdr->e_phoff), + ehdr->e_phnum, ehdr->e_phentsize, lib); lib->dynv = (void *)(lib->base + find_dyn( (void *)(aux[AT_BASE]+ehdr->e_phoff), ehdr->e_phnum, ehdr->e_phentsize)); @@ -666,6 +685,8 @@ void *__dynlink(int argc, char **argv) app->name = argv[0]; app->dynv = (void *)(app->base + find_dyn( (void *)aux[AT_PHDR], aux[AT_PHNUM], aux[AT_PHENT])); + find_map_range((void *)aux[AT_PHDR], + aux[AT_PHNUM], aux[AT_PHENT], app); } else { int fd; char *ldname = argv[0]; @@ -891,6 +912,67 @@ failed: return 0; } +int __dladdr(void *addr, Dl_info *info) +{ + struct dso *p; + Sym *sym; + uint32_t nsym; + char *strings; + size_t i; + void *best = 0; + char *bestname; + + pthread_rwlock_rdlock(&lock); + for (p=head; p && (unsigned char *)addr-p->map>p->map_len; p=p->next); + pthread_rwlock_unlock(&lock); + + if (!p) return 0; + + sym = p->syms; + strings = p->strings; + if (p->hashtab) { + nsym = p->hashtab[1]; + } else { + uint32_t *buckets; + uint32_t *hashval; + buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4); + sym += p->ghashtab[1]; + for (i = 0; i < p->ghashtab[0]; i++) { + if (buckets[i] > nsym) + nsym = buckets[i]; + } + if (nsym) { + nsym -= p->ghashtab[1]; + hashval = buckets + p->ghashtab[0] + nsym; + do nsym++; + while (!(*hashval++ & 1)); + } + } + + for (; nsym; nsym--, sym++) { + if (sym->st_shndx && sym->st_value + && (1<<(sym->st_info&0xf) & OK_TYPES) + && (1<<(sym->st_info>>4) & OK_BINDS)) { + void *symaddr = p->base + sym->st_value; + if (symaddr > addr || symaddr < best) + continue; + best = symaddr; + bestname = strings + sym->st_name; + if (addr == symaddr) + break; + } + } + + if (!best) return 0; + + info->dli_fname = p->name; + info->dli_fbase = p->base; + info->dli_sname = bestname; + info->dli_saddr = best; + + return 1; +} + void *__dlsym(void *p, const char *s, void *ra) { void *res; @@ -908,6 +990,10 @@ void *__dlsym(void *p, const char *s, void *ra) { return 0; } +int __dladdr (void *addr, Dl_info *info) +{ + return 0; +} #endif char *dlerror() |