make dlerror conform to posix

[musl] / src / ldso / dynlink.c

diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index 01c7f29..e0013ec 100644 (file)
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -1,4 +1,3 @@
-#ifdef __PIC__
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -18,6 +17,10 @@
 #include <ctype.h>
 #include <dlfcn.h>
 
+static int errflag;
+
+#ifdef __PIC__
+
 #include "reloc.h"
 
 #if ULONG_MAX == 0xffffffff
@@ -47,9 +50,9 @@ struct dso
        size_t map_len;
        dev_t dev;
        ino_t ino;
-       int global;
-       int relocated;
-       int constructed;
+       char global;
+       char relocated;
+       char constructed;
        struct dso **deps;
        char *name;
        char buf[];
@@ -610,9 +613,11 @@ void *dlopen(const char *file, int mode)
 {
        struct dso *volatile p, *orig_tail = tail, *next;
        size_t i;
+       int cs;
 
        if (!file) return head;
 
+       pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
        pthread_rwlock_wrlock(&lock);
 
        if (setjmp(rtld_fail)) {
@@ -628,12 +633,13 @@ void *dlopen(const char *file, int mode)
                }
                tail = orig_tail;
                tail->next = 0;
-               pthread_rwlock_unlock(&lock);
-               return 0;
-       }
+               p = 0;
+       } else p = load_library(file);
 
-       p = load_library(file);
-       if (!p) goto end;
+       if (!p) {
+               errflag = 1;
+               goto end;
+       }
 
        /* First load handling */
        if (!p->deps) {
@@ -658,6 +664,7 @@ void *dlopen(const char *file, int mode)
        do_init_fini(tail);
 end:
        pthread_rwlock_unlock(&lock);
+       pthread_setcancelstate(cs, 0);
        return p;
 }
 
@@ -671,8 +678,11 @@ static void *do_dlsym(struct dso *p, const char *s, void *ra)
                if (!p) p=head;
                p=p->next;
        }
-       if (p == head || p == RTLD_DEFAULT)
-               return find_sym(head, s, 0);
+       if (p == head || p == RTLD_DEFAULT) {
+               void *res = find_sym(head, s, 0);
+               if (!res) errflag = 1;
+               return res;
+       }
        h = hash(s);
        sym = lookup(s, h, p->syms, p->hashtab, p->strings);
        if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
@@ -683,6 +693,7 @@ static void *do_dlsym(struct dso *p, const char *s, void *ra)
                if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
                        return p->deps[i]->base + sym->st_value;
        }
+       errflag = 1;
        return 0;
 }
 
@@ -707,6 +718,8 @@ void *__dlsym(void *p, const char *s, void *ra)
 
 char *dlerror()
 {
+       if (!errflag) return 0;
+       errflag = 0;
        return "unknown error";
 }