Revert "Fix the C library initialization to avoid calling static C++ constructors twice."

This reverts commit 03eabfe65e.

libc/arch-arm/bionic/crtbegin_dynamic.S

@@ -30,35 +30,25 @@
 	.type _start,#function
 	.globl _start
 
-# This is the small startup code that is called from
+# this is the small startup code that is first run when
-# the dynamic linker to execute an executable once all
+# any executable that is statically-linked with Bionic
-# dependent shared libraries have been loaded and
+# runs.
-# initialized.
 #
-# It's purpose is to call __libc_init as defined in
+# it's purpose is to call __libc_init with appropriate
-# bionic/libc_init_dynamic.c with appropriate
 # arguments, which are:
 #
 #    - the address of the raw data block setup by the Linux
 #      kernel ELF loader
 #
-#    - address of an "onexit" function (not used on any
+#    - address of an "onexit" function, not used on any
-#      platform supported by Bionic)
+#      platform supported by Bionic
 #
 #    - address of the "main" function of the program. We
 #      can't hard-code it in the adr pseudo instruction
 #      so we use a tiny trampoline that will get relocated
 #      by the dynamic linker before this code runs
 #
-#    - address of the constructors table, i.e. a table
+#    - address of the constructor list
-#      that points to various initialization and
-#      finalization sections for the program.
-#
-# NOTE: This code is currently placed in shared libraries
-#       by the build system, but will be ignored.
-#
-#       On the other hand, the arrays defined below are
-#       required and will be parsed by the dynamic linker.
 #
 _start:	
 	mov	r0, sp
@@ -73,7 +63,7 @@ _start:
     .long   __INIT_ARRAY__
     .long   __FINI_ARRAY__
     .long   __CTOR_LIST__
-
+      
 # the .ctors section contains a list of pointers to "constructor"
 # functions that need to be called in order during C library initialization,
 # just before the program is being run. This is a C++ requirement

libc/arch-arm/bionic/crtbegin_static.S

@@ -30,27 +30,25 @@
 	.type _start,#function
 	.globl _start
 
-# This is the small startup code that is first run when
+# this is the small startup code that is first run when
-# any static executable runs. A static executable is one
+# any executable that is statically-linked with Bionic
-# that is started directly by the Linux kernel, not from
+# runs.
-# the dynamic linker, it thus cannot depend on any shared
-# library.
 #
-# It's purpose is to call __libc_init as defined in
+# it's purpose is to call __libc_init with appropriate
-# bionic/libc_init_static.c with appropriate
 # arguments, which are:
 #
 #    - the address of the raw data block setup by the Linux
 #      kernel ELF loader
 #
-#    - address of an "onexit" function (not used on any
+#    - address of an "onexit" function, not used on any
-#      platform supported by Bionic).
+#      platform supported by Bionic
 #
-#    - address of the "main" function of the program.
+#    - address of the "main" function of the program. We
+#      can't hard-code it in the adr pseudo instruction
+#      so we use a tiny trampoline that will get relocated
+#      by the dynamic linker before this code runs
 #
-#    - address of the constructors table, i.e. a table
+#    - address of the constructor list
-#      that points to various initialization and
-#      finalization sections for the program.
 #
 _start:	
 	mov	r0, sp
@@ -61,18 +59,11 @@ _start:
 
 0:  b   main
 
-# The "C++ ABI for ARM" document that static C++ constructors
-# shall only be called from the .init_array section.
-#
-# Do we really need a .ctors section on ARM platforms ?
-# It looks like it will always be empty.
-#
-
 1:  .long   __PREINIT_ARRAY__
     .long   __INIT_ARRAY__
     .long   __FINI_ARRAY__
     .long   __CTOR_LIST__
-
+      
 # the .ctors section contains a list of pointers to "constructor"
 # functions that need to be called in order during C library initialization,
 # just before the program is being run. This is a C++ requirement

libc/arch-x86/bionic/crtbegin_dynamic.S

@@ -29,35 +29,25 @@
 	.type _start, @function
 	.globl _start
 
-# This is the small startup code that is called from
+# this is the small startup code that is first run when
-# the dynamic linker to execute an executable once all
+# any executable that is statically-linked with Bionic
-# dependent shared libraries have been loaded and
+# runs.
-# initialized.
 #
-# It's purpose is to call __libc_init as defined in
+# it's purpose is to call __libc_init with appropriate
-# bionic/libc_init_dynamic.c with appropriate
 # arguments, which are:
 #
 #    - the address of the raw data block setup by the Linux
 #      kernel ELF loader
 #
-#    - address of an "onexit" function (not used on any
+#    - address of an "onexit" function, not used on any
-#      platform supported by Bionic)
+#      platform supported by Bionic
 #
 #    - address of the "main" function of the program. We
 #      can't hard-code it in the adr pseudo instruction
 #      so we use a tiny trampoline that will get relocated
 #      by the dynamic linker before this code runs
 #
-#    - address of the constructors table, i.e. a table
+#    - address of the constructor list
-#      that points to various initialization and
-#      finalization sections for the program.
-#
-# NOTE: This code is currently placed in shared libraries
-#       by the build system, but will be ignored.
-#
-#       On the other hand, the arrays defined below are
-#       required and will be parsed by the dynamic linker.
 #
 _start:	
         mov     %esp, %eax

libc/arch-x86/bionic/crtbegin_static.S

@@ -29,27 +29,25 @@
 	.type _start, @function
 	.globl _start
 
-# This is the small startup code that is first run when
+# this is the small startup code that is first run when
-# any static executable runs. A static executable is one
+# any executable that is statically-linked with Bionic
-# that is started directly by the Linux kernel, not from
+# runs.
-# the dynamic linker, it thus cannot depend on any shared
-# library.
 #
-# It's purpose is to call __libc_init as defined in
+# it's purpose is to call __libc_init with appropriate
-# bionic/libc_init_static.c with appropriate
 # arguments, which are:
 #
 #    - the address of the raw data block setup by the Linux
 #      kernel ELF loader
 #
-#    - address of an "onexit" function (not used on any
+#    - address of an "onexit" function, not used on any
-#      platform supported by Bionic).
+#      platform supported by Bionic
 #
-#    - address of the "main" function of the program.
+#    - address of the "main" function of the program. We
+#      can't hard-code it in the adr pseudo instruction
+#      so we use a tiny trampoline that will get relocated
+#      by the dynamic linker before this code runs
 #
-#    - address of the constructors table, i.e. a table
+#    - address of the constructor list
-#      that points to various initialization and
-#      finalization sections for the program.
 #
 _start:	
         mov     %esp, %eax

libc/bionic/libc_init_common.c

@@ -39,11 +39,8 @@
 #include <bionic_tls.h>
 #include <errno.h>
 
-/* This contains the common C library initialization code.
+extern void _init(void);
- * To understand what happens here, you should read the
+extern void _fini(void);
- * "Initialization and Finalization" section of the file
- * named bionic/linker/README.TXT
- */
 
 static void call_array(void(**list)())
 {
@@ -53,6 +50,15 @@ static void call_array(void(**list)())
     }
 }
 
+static void __bionic_do_global_dtors(structors_array_t const * const p)
+{
+    call_array(p->fini_array);
+    //_fini();
+}
+
+extern unsigned __get_sp(void);
+extern pid_t    gettid(void);
+
 char*  __progname;
 char **environ;
 
@@ -63,28 +69,30 @@ unsigned int __page_shift = PAGE_SHIFT;
 
 int __system_properties_init(void);
 
-/* This function can be run under two different contexts:
- *
- * - for statically linked executables (i.e. those who do
- *   not depend on shared libraries at all), it will be
- *   called from the __libc_init() function defined in
- *   bionic/libc_init_static.c
- *
- * - for dynamic executables, it will be called from the
- *   __libc_init() function defined in bionic/libc_init_dynamic.c
- *
- */
 void __libc_init_common(uintptr_t *elfdata,
                        void (*onexit)(void),
                        int (*slingshot)(int, char**, char**),
                        structors_array_t const * const structors,
                        void (*pre_ctor_hook)())
 {
+    pthread_internal_t thread;
+    pthread_attr_t thread_attr;
+    void *tls_area[BIONIC_TLS_SLOTS];
     int argc;
     char **argv, **envp, **envend;
     struct auxentry *auxentry;
     unsigned int page_size = 0, page_shift = 0;
 
+    /* The main thread's stack has empirically shown to be 84k */
+    unsigned stacktop = (__get_sp() & ~(PAGE_SIZE - 1)) + PAGE_SIZE;
+    unsigned stacksize = 128 * 1024; //84 * 1024;
+    unsigned stackbottom = stacktop - stacksize;
+
+    pthread_attr_init(&thread_attr);
+    pthread_attr_setstack(&thread_attr, (void*)stackbottom, stacksize);
+    _init_thread(&thread, gettid(), &thread_attr, (void*)stackbottom);
+    __init_tls(tls_area, &thread);
+
     argc = (int) *elfdata++;
     argv = (char**) elfdata;
     envp = argv+(argc+1);
@@ -98,17 +106,17 @@ void __libc_init_common(uintptr_t *elfdata,
 
     if (pre_ctor_hook) pre_ctor_hook();
 
-    if (structors != NULL) {
+    // XXX: we should execute the .fini_array upon exit
-        // pre-init array.
-        call_array(structors->preinit_array);
 
-        // for compatibility with non-eabi binary, call the .ctors section
+    // pre-init array.
-        // this is only useful for static non-ARM (e.g. x86) executables.
+    // XXX: I'm not sure what's the different with the init array.
-        call_array(structors->ctors_array);
+    call_array(structors->preinit_array);
 
-        // call static constructors
+    // for compatibility with non-eabi binary, call the .ctors section
-        call_array(structors->init_array);
+    call_array(structors->ctors_array);
-    }
+
+    // call static constructors
+    call_array(structors->init_array);
 
     exit(slingshot(argc, argv, envp));
 }

libc/bionic/libc_init_dynamic.c

@@ -25,29 +25,18 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
-
 /*
  * libc_init_static.c
  *
- * This function is called for dynamic executables after the dynamic
+ * This function takes the raw data block set up by the ELF loader
- * linker has loaded and initialized all dependent shared libraries.
+ * in the kernel and parses it.  It is invoked by crt0.S which makes
- *
+ * any necessary adjustments and passes calls this function using
- * It takes the raw data block set up by the ELF loader
+ * the standard C calling convention.
- * in the kernel and parses it.
  *
  * The arguments are:
- *      elfdata   -- The ELF loader data block; usually from the stack.
+ *  uintptr_t *elfdata	 -- The ELF loader data block; usually from the stack.
- *                   Basically a pointer to argc.
+ *                          Basically a pointer to argc.
- *
+ *  void (*onexit)(void) -- Function to install into onexit
- *      onexit    -- Function to call on exit, can be NULL.
- *
- *      slingshot -- Address of the program's main function
- *
- *      structors -- Table of constructor functions arrays that must
- *                   be called before the slingshot.
- *
- * It is called from the assembly fragment found in
- * arch-$ARCH/bionic/crtbegin_dynamic.S
  */
 
 /*
@@ -73,18 +62,5 @@ __noreturn void __libc_init(uintptr_t *elfdata,
                        int (*slingshot)(int, char**, char**),
                        structors_array_t const * const structors)
 {
-    /* NOTE: At this point, the dynamic linker has *already* called
+    __libc_init_common(elfdata, onexit, slingshot, structors, malloc_debug_init);
-     *       all initializers properly, so we ignore 'structors' to
-     *       avoid calling them twice.
-     */
-
-    /* NOTE2: Is it worthwhile to use malloc_debug_init() in the case of
-     *        of the non-debug shared C library ?
-     *
-     *        The implementation in bionic/malloc_leak.c contains a lot
-     *        of code which will turn to be unused, and we add a dispatch
-     *        overhead to malloc() et al. that proved to be significant
-     *        in the past (e.g. making boot sequence 5% slower)
-     */
-    __libc_init_common(elfdata, onexit, slingshot, NULL, malloc_debug_init);
 }

libc/bionic/libc_init_static.c

@@ -25,30 +25,18 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
-
 /*
  * libc_init_static.c
  *
- * This function is called for static executables, i.e. those that
+ * This function takes the raw data block set up by the ELF loader
- * dont depend on shared libraries and are directly started by the
+ * in the kernel and parses it.  It is invoked by crt0.S which makes
- * Linux kernel.
+ * any necessary adjustments and passes calls this function using
- *
+ * the standard C calling convention.
- * It takes the raw data block set up by the ELF loader
- * in the kernel and parses it.
  *
  * The arguments are:
- *      elfdata   -- The ELF loader data block; usually from the stack.
+ *  uintptr_t *elfdata	 -- The ELF loader data block; usually from the stack.
- *                   Basically a pointer to argc.
+ *                          Basically a pointer to argc.
- *
+ *  void (*onexit)(void) -- Function to install into onexit
- *      onexit    -- Function to call on exit, can be NULL.
- *
- *      slingshot -- Address of the program's main function
- *
- *      structors -- Table of constructor functions arrays that must
- *                   be called before the slingshot.
- *
- * It is called from the assembly fragment found in
- * arch-$ARCH/bionic/crtbegin_static.S
  */
 
 /*
@@ -63,19 +51,18 @@
 #include <stdlib.h>
 #include <stdint.h>
 #include <elf.h>
-#include "bionic_preinit.h"
+#include "pthread_internal.h"
+#include "atexit.h"
 #include "libc_init_common.h"
 
+#include <bionic_tls.h>
+#include <errno.h>
+
 __noreturn void __libc_init(uintptr_t *elfdata,
                        void (*onexit)(void),
                        int (*slingshot)(int, char**, char**),
                        structors_array_t const * const structors)
 {
-    pthread_internal_t thread;
-    void *tls_area[BIONIC_TLS_SLOTS];
-
-    __libc_preinit( &thread, tls_area );
-
 /* 
  * To enable malloc checks for statically linked programs, add
  * "WITH_MALLOC_CHECK_LIBC_A := true" in device/buildspec.mk

libc/private/bionic_preinit.h

@@ -1,76 +0,0 @@
-/*
- * Copyright (C) 2009 The Android Open Source Project
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *  * Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- *  * Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#ifndef _BIONIC_PREINIT_H
-#define _BIONIC_PREINIT_H
-
-#include "pthread_internal.h"
-#include "bionic_tls.h"
-#include <asm/page.h>
-
-/* this function is used to perform a minimal initialization of the
- * the C library. This must be performed before any other call to
- * other functions, in either the dynamic linker's startup code
- * or libc_init_static.c
- *
- * 'main_thread' and 'tls_area' must be persistent variables,
- * which means they must be either global, or allocated in the
- * main thread's stack frame and never, ever, freed before
- * program exit.
- *
- * VERY IMPORTANT NOTE:
- *
- *   THIS IMPLEMENTATION SHOULD NOT USE GLOBAL VARIABLES.
- *
- *   The reason is the dynamic linker's tricky usage of C library
- *   functions and later renaming of their symbols. See the
- *   "C Library Usage Restriction" section in bionic/linker/README.TXT
- *   for details.
- */
-
-extern unsigned __get_sp(void);
-extern pid_t    gettid(void);
-
-static __inline__ void
-__libc_preinit( pthread_internal_t*  main_thread,
-                void*                tls_area[BIONIC_TLS_SLOTS] )
-{
-    pthread_attr_t  thread_attr;
-
-    /* Setup the main thread's information */
-    unsigned stacktop = (__get_sp() & ~(PAGE_SIZE - 1)) + PAGE_SIZE;
-    unsigned stacksize = 128 * 1024;
-    unsigned stackbottom = stacktop - stacksize;
-
-    pthread_attr_init(&thread_attr);
-    pthread_attr_setstack(&thread_attr, (void*)stackbottom, stacksize);
-    _init_thread(main_thread, gettid(), &thread_attr, (void*)stackbottom);
-    __init_tls(tls_area, main_thread);
-}
-
-#endif /* _BIONIC_INIT_H */

linker/README.TXT

@@ -112,46 +112,3 @@ On x86, the lists of constructors and destructors are placed in special
 sections named ".ctors" and ".dtors", and the DT_INIT / DT_FINI functions
 are in charge of calling them explicitely.
 
-
-C Library Usage Restrictions:
------------------------------
-
-The dynamic linker executable (/system/bin/linker) is built using the
-static version of the C library (libc.a), in order to use various functions
-and system calls provided by it.
-
-However, it will normally, at runtime, map the shared library version
-of the C library (/system/lib/libc.so) as well in the process' address
-space. This means that:
-
-- any global variable defined by the C library will appear twice in
-  the process address space, at different addresses.
-
-- some functions will be duplicated too, though those that refer to
-  global variables will refer to distinct addresses.
-
-This can lead to subtle conflicts, typically for process-specific data that
-is managed through the kernel. A good example is the handling of the
-end of the data segment, which is normally done through the 'sbrk' or
-'brk' system call by the malloc implementation.
-
-If two similar, but distinct, malloc implementations run at the same time,
-and if each one thinks it exclusively manages some process settings, hideous
-corruption or crashes may occur.
-
-For this very reason, THE DYNAMIC LINKER CANNOT USE malloc()/free() !
-That's why it is linked to a special version of the C library that will
-abort when any of these functions (or calloc()/realloc()) is called.
-
-Moreover, it cannot use any C library feature that could use these
-indirectly. Experience as shown that this meant:
-
-- avoiding any FILE* - related stdio function (fopen, fread, fprintf, etc...)
-- avoiding snprintf() with any floating-point formatter ("%f", "%g")
-
-There are probably other cases that haven't been discovered yet, so the
-code needs to be very frugal in its use of the C library.
-
-This also explains why the linker's tracing macros are all disabled by
-default. Enabling them sometimes creates problems, depending on the process
-being loaded, so they should be considered an experimental feature for now.

linker/linker.c

@@ -44,7 +44,7 @@
 #include <sys/atomics.h>
 
 /* special private C library header - see Android.mk */
-#include <bionic_preinit.h>
+#include <bionic_tls.h>
 
 #include "linker.h"
 #include "linker_debug.h"
@@ -1691,7 +1691,6 @@ int main(int argc, char **argv)
 #define ANDROID_TLS_SLOTS  BIONIC_TLS_SLOTS
 
 static void * __tls_area[ANDROID_TLS_SLOTS];
-static pthread_internal_t  __main_thread;
 
 unsigned __linker_init(unsigned **elfdata)
 {
@@ -1710,7 +1709,8 @@ unsigned __linker_init(unsigned **elfdata)
     gettimeofday(&t0, 0);
 #endif
 
-    __libc_preinit(&__main_thread, __tls_area);
+    __set_tls(__tls_area);
+    ((unsigned *)__get_tls())[TLS_SLOT_THREAD_ID] = gettid();
 
     debugger_init();