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-rw-r--r--include/dlfcn.h10
-rw-r--r--src/ldso/dladdr.c9
-rw-r--r--src/ldso/dynlink.c86
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()