From a9e85c0a5c690086c652f3a8ae9a109389f671a3 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Fri, 23 Mar 2012 00:28:20 -0400 Subject: [PATCH] make dlerror conform to posix the error status is required to be sticky after failure of dlopen or dlsym until cleared by dlerror. applications and especially libraries should never rely on this since it is not thread-safe and subject to race conditions, but glib does anyway. --- src/ldso/dynlink.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c index 6ff8850c..e0013ec0 100644 --- a/src/ldso/dynlink.c +++ b/src/ldso/dynlink.c @@ -1,4 +1,3 @@ -#ifdef __PIC__ #include #include #include @@ -18,6 +17,10 @@ #include #include +static int errflag; + +#ifdef __PIC__ + #include "reloc.h" #if ULONG_MAX == 0xffffffff @@ -631,12 +634,13 @@ void *dlopen(const char *file, int mode) tail = orig_tail; tail->next = 0; p = 0; + } else p = load_library(file); + + if (!p) { + errflag = 1; goto end; } - p = load_library(file); - if (!p) goto end; - /* First load handling */ if (!p->deps) { load_deps(p); @@ -674,8 +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)) @@ -686,6 +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; } @@ -710,6 +718,8 @@ void *__dlsym(void *p, const char *s, void *ra) char *dlerror() { + if (!errflag) return 0; + errflag = 0; return "unknown error"; } -- 2.25.1